terminal.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <ctype.h>
   4
   5 #include <time.h>
   6 #include <assert.h>
   7 #include "putty.h"
   8 #include "terminal.h"
   9
  10 #define poslt(p1,p2) ( (p1).y < (p2).y || ( (p1).y == (p2).y && (p1).x < (p2).x ) )
  11 #define posle(p1,p2) ( (p1).y < (p2).y || ( (p1).y == (p2).y && (p1).x <= (p2).x ) )
  12 #define poseq(p1,p2) ( (p1).y == (p2).y && (p1).x == (p2).x )
  13 #define posdiff(p1,p2) ( ((p1).y - (p2).y) * (term->cols+1) + (p1).x - (p2).x )
  14
  15 /* Product-order comparisons for rectangular block selection. */
  16 #define posPlt(p1,p2) ( (p1).y <= (p2).y && (p1).x < (p2).x )
  17 #define posPle(p1,p2) ( (p1).y <= (p2).y && (p1).x <= (p2).x )
  18
  19 #define incpos(p) ( (p).x == term->cols ? ((p).x = 0, (p).y++, 1) : ((p).x++, 0) )
  20 #define decpos(p) ( (p).x == 0 ? ((p).x = term->cols, (p).y--, 1) : ((p).x--, 0) )
  21
  22 #define VT52_PLUS
  23
  24 #define CL_ANSIMIN      0x0001         /* Codes in all ANSI like terminals. */
  25 #define CL_VT100        0x0002         /* VT100 */
  26 #define CL_VT100AVO     0x0004         /* VT100 +AVO; 132x24 (not 132x14) & attrs */
  27 #define CL_VT102        0x0008         /* VT102 */
  28 #define CL_VT220        0x0010         /* VT220 */
  29 #define CL_VT320        0x0020         /* VT320 */
  30 #define CL_VT420        0x0040         /* VT420 */
  31 #define CL_VT510        0x0080         /* VT510, NB VT510 includes ANSI */
  32 #define CL_VT340TEXT    0x0100         /* VT340 extensions that appear in the VT420 */
  33 #define CL_SCOANSI      0x1000         /* SCOANSI not in ANSIMIN. */
  34 #define CL_ANSI         0x2000         /* ANSI ECMA-48 not in the VT100..VT420 */
  35 #define CL_OTHER        0x4000         /* Others, Xterm, linux, putty, dunno, etc */
  36
  37 #define TM_VT100        (CL_ANSIMIN|CL_VT100)
  38 #define TM_VT100AVO     (TM_VT100|CL_VT100AVO)
  39 #define TM_VT102        (TM_VT100AVO|CL_VT102)
  40 #define TM_VT220        (TM_VT102|CL_VT220)
  41 #define TM_VTXXX        (TM_VT220|CL_VT340TEXT|CL_VT510|CL_VT420|CL_VT320)
  42 #define TM_SCOANSI      (CL_ANSIMIN|CL_SCOANSI)
  43
  44 #define TM_PUTTY        (0xFFFF)
  45
  46 #define compatibility(x) \
  47     if ( ((CL_##x)&term->compatibility_level) == 0 ) {  \
  48        term->termstate=TOPLEVEL;                        \
  49        break;                                           \
  50     }
  51 #define compatibility2(x,y) \
  52     if ( ((CL_##x|CL_##y)&term->compatibility_level) == 0 ) { \
  53        term->termstate=TOPLEVEL;                        \
  54        break;                                           \
  55     }
  56
  57 #define has_compat(x) ( ((CL_##x)&term->compatibility_level) != 0 )
  58
  59 #define sel_nl_sz  (sizeof(sel_nl)/sizeof(wchar_t))
  60 const wchar_t sel_nl[] = SEL_NL;
  61
  62 /*
  63  * Fetch the character at a particular position in a line array,
  64  * for purposes of `wordtype'. The reason this isn't just a simple
  65  * array reference is that if the character we find is UCSWIDE,
  66  * then we must look one space further to the left.
  67  */
  68 #define UCSGET(a, x) \
  69     ( (x)>0 && ((a)[(x)] & (CHAR_MASK | CSET_MASK)) == UCSWIDE ? \
  70         (a)[(x)-1] : (a)[(x)] )
  71
  72 /*
  73  * Internal prototypes.
  74  */
  75 static unsigned long *resizeline(unsigned long *, int);
  76 static unsigned long *lineptr(Terminal *, int, int);
  77 static void do_paint(Terminal *, Context, int);
  78 static void erase_lots(Terminal *, int, int, int);
  79 static void swap_screen(Terminal *, int, int, int);
  80 static void update_sbar(Terminal *);
  81 static void deselect(Terminal *);
  82 static void term_print_finish(Terminal *);
  83 #ifdef OPTIMISE_SCROLL
  84 static void scroll_display(Terminal *, int, int, int);
  85 #endif /* OPTIMISE_SCROLL */
  86
  87 /*
  88  * Resize a line to make it `cols' columns wide.
  89  */
  90 static unsigned long *resizeline(unsigned long *line, int cols)
  91 {
  92     int i, oldlen;
  93     unsigned long lineattrs;
  94
  95     if (line[0] != (unsigned long)cols) {
  96         /*
  97          * This line is the wrong length, which probably means it
  98          * hasn't been accessed since a resize. Resize it now.
  99          */
 100         oldlen = line[0];
 101         lineattrs = line[oldlen + 1];
 102         line = srealloc(line, TSIZE * (2 + cols));
 103         line[0] = cols;
 104         for (i = oldlen; i < cols; i++)
 105             line[i + 1] = ERASE_CHAR;
 106         line[cols + 1] = lineattrs & LATTR_MODE;
 107     }
 108
 109     return line;
 110 }
 111
 112 /*
 113  * Retrieve a line of the screen or of the scrollback, according to
 114  * whether the y coordinate is non-negative or negative
 115  * (respectively).
 116  */
 117 static unsigned long *lineptr(Terminal *term, int y, int lineno)
 118 {
 119     unsigned long *line, *newline;
 120     tree234 *whichtree;
 121     int treeindex;
 122
 123     if (y >= 0) {
 124         whichtree = term->screen;
 125         treeindex = y;
 126     } else {
 127         whichtree = term->scrollback;
 128         treeindex = y + count234(term->scrollback);
 129     }
 130     line = index234(whichtree, treeindex);
 131
 132     /* We assume that we don't screw up and retrieve something out of range. */
 133     assert(line != NULL);
 134
 135     newline = resizeline(line, term->cols);
 136     if (newline != line) {
 137         delpos234(whichtree, treeindex);
 138         addpos234(whichtree, newline, treeindex);
 139         line = newline;
 140     }
 141
 142     return line + 1;
 143 }
 144
 145 #define lineptr(x) lineptr(term,x,__LINE__)
 146
 147 /*
 148  * Set up power-on settings for the terminal.
 149  */
 150 static void power_on(Terminal *term)
 151 {
 152     term->curs.x = term->curs.y = 0;
 153     term->alt_x = term->alt_y = 0;
 154     term->savecurs.x = term->savecurs.y = 0;
 155     term->alt_t = term->marg_t = 0;
 156     if (term->rows != -1)
 157         term->alt_b = term->marg_b = term->rows - 1;
 158     else
 159         term->alt_b = term->marg_b = 0;
 160     if (term->cols != -1) {
 161         int i;
 162         for (i = 0; i < term->cols; i++)
 163             term->tabs[i] = (i % 8 == 0 ? TRUE : FALSE);
 164     }
 165     term->alt_om = term->dec_om = term->cfg.dec_om;
 166     term->alt_ins = term->insert = FALSE;
 167     term->alt_wnext = term->wrapnext = term->save_wnext = FALSE;
 168     term->alt_wrap = term->wrap = term->cfg.wrap_mode;
 169     term->alt_cset = term->cset = term->save_cset = 0;
 170     term->alt_utf = term->utf = term->save_utf = 0;
 171     term->utf_state = 0;
 172     term->alt_sco_acs = term->sco_acs = term->save_sco_acs = 0;
 173     term->cset_attr[0] = term->cset_attr[1] = term->save_csattr = ATTR_ASCII;
 174     term->rvideo = 0;
 175     term->in_vbell = FALSE;
 176     term->cursor_on = 1;
 177     term->big_cursor = 0;
 178     term->save_attr = term->curr_attr = ATTR_DEFAULT;
 179     term->term_editing = term->term_echoing = FALSE;
 180     term->app_cursor_keys = term->cfg.app_cursor;
 181     term->app_keypad_keys = term->cfg.app_keypad;
 182     term->use_bce = term->cfg.bce;
 183     term->blink_is_real = term->cfg.blinktext;
 184     term->erase_char = ERASE_CHAR;
 185     term->alt_which = 0;
 186     term_print_finish(term);
 187     {
 188         int i;
 189         for (i = 0; i < 256; i++)
 190             term->wordness[i] = term->cfg.wordness[i];
 191     }
 192     if (term->screen) {
 193         swap_screen(term, 1, FALSE, FALSE);
 194         erase_lots(term, FALSE, TRUE, TRUE);
 195         swap_screen(term, 0, FALSE, FALSE);
 196         erase_lots(term, FALSE, TRUE, TRUE);
 197     }
 198 }
 199
 200 /*
 201  * Force a screen update.
 202  */
 203 void term_update(Terminal *term)
 204 {
 205     Context ctx;
 206     ctx = get_ctx(term->frontend);
 207     if (ctx) {
 208         int need_sbar_update = term->seen_disp_event;
 209         if (term->seen_disp_event && term->cfg.scroll_on_disp) {
 210             term->disptop = 0;         /* return to main screen */
 211             term->seen_disp_event = 0;
 212             need_sbar_update = TRUE;
 213         }
 214         if (need_sbar_update)
 215             update_sbar(term);
 216         do_paint(term, ctx, TRUE);
 217         sys_cursor(term->frontend, term->curs.x, term->curs.y - term->disptop);
 218         free_ctx(ctx);
 219     }
 220 }
 221
 222 /*
 223  * Called from front end when a keypress occurs, to trigger
 224  * anything magical that needs to happen in that situation.
 225  */
 226 void term_seen_key_event(Terminal *term)
 227 {
 228     /*
 229      * On any keypress, clear the bell overload mechanism
 230      * completely, on the grounds that large numbers of
 231      * beeps coming from deliberate key action are likely
 232      * to be intended (e.g. beeps from filename completion
 233      * blocking repeatedly).
 234      */
 235     term->beep_overloaded = FALSE;
 236     while (term->beephead) {
 237         struct beeptime *tmp = term->beephead;
 238         term->beephead = tmp->next;
 239         sfree(tmp);
 240     }
 241     term->beeptail = NULL;
 242     term->nbeeps = 0;
 243
 244     /*
 245      * Reset the scrollback on keypress, if we're doing that.
 246      */
 247     if (term->cfg.scroll_on_key) {
 248         term->disptop = 0;             /* return to main screen */
 249         term->seen_disp_event = 1;
 250     }
 251 }
 252
 253 /*
 254  * Same as power_on(), but an external function.
 255  */
 256 void term_pwron(Terminal *term)
 257 {
 258     power_on(term);
 259     if (term->ldisc)                   /* cause ldisc to notice changes */
 260         ldisc_send(term->ldisc, NULL, 0, 0);
 261     fix_cpos;
 262     term->disptop = 0;
 263     deselect(term);
 264     term_update(term);
 265 }
 266
 267 /*
 268  * When the user reconfigures us, we need to check the forbidden-
 269  * alternate-screen config option, disable raw mouse mode if the
 270  * user has disabled mouse reporting, and abandon a print job if
 271  * the user has disabled printing.
 272  */
 273 void term_reconfig(Terminal *term, Config *cfg)
 274 {
 275     /*
 276      * Before adopting the new config, check all those terminal
 277      * settings which control power-on defaults; and if they've
 278      * changed, we will modify the current state as well as the
 279      * default one. The full list is: Auto wrap mode, DEC Origin
 280      * Mode, BCE, blinking text, character classes.
 281      */
 282     int reset_wrap, reset_decom, reset_bce, reset_blink, reset_charclass;
 283     int i;
 284
 285     reset_wrap = (term->cfg.wrap_mode != cfg->wrap_mode);
 286     reset_decom = (term->cfg.dec_om != cfg->dec_om);
 287     reset_bce = (term->cfg.bce != cfg->bce);
 288     reset_blink = (term->cfg.blinktext != cfg->blinktext);
 289     reset_charclass = 0;
 290     for (i = 0; i < lenof(term->cfg.wordness); i++)
 291         if (term->cfg.wordness[i] != cfg->wordness[i])
 292             reset_charclass = 1;
 293
 294     term->cfg = *cfg;                  /* STRUCTURE COPY */
 295
 296     if (reset_wrap)
 297         term->alt_wrap = term->wrap = term->cfg.wrap_mode;
 298     if (reset_decom)
 299         term->alt_om = term->dec_om = term->cfg.dec_om;
 300     if (reset_bce)
 301         term->use_bce = term->cfg.bce;
 302     if (reset_blink)
 303         term->blink_is_real = term->cfg.blinktext;
 304     if (reset_charclass)
 305         for (i = 0; i < 256; i++)
 306             term->wordness[i] = term->cfg.wordness[i];
 307
 308     if (term->cfg.no_alt_screen)
 309         swap_screen(term, 0, FALSE, FALSE);
 310     if (term->cfg.no_mouse_rep) {
 311         term->xterm_mouse = 0;
 312         set_raw_mouse_mode(term->frontend, 0);
 313     }
 314     if (term->cfg.no_remote_charset) {
 315         term->cset_attr[0] = term->cset_attr[1] = ATTR_ASCII;
 316         term->sco_acs = term->alt_sco_acs = 0;
 317         term->utf = 0;
 318     }
 319     if (!*term->cfg.printer) {
 320         term_print_finish(term);
 321     }
 322 }
 323
 324 /*
 325  * Clear the scrollback.
 326  */
 327 void term_clrsb(Terminal *term)
 328 {
 329     unsigned long *line;
 330     term->disptop = 0;
 331     while ((line = delpos234(term->scrollback, 0)) != NULL) {
 332         sfree(line);
 333     }
 334     update_sbar(term);
 335 }
 336
 337 /*
 338  * Initialise the terminal.
 339  */
 340 Terminal *term_init(Config *mycfg, struct unicode_data *ucsdata,
 341                     void *frontend)
 342 {
 343     Terminal *term;
 344
 345     /*
 346      * Allocate a new Terminal structure and initialise the fields
 347      * that need it.
 348      */
 349     term = smalloc(sizeof(Terminal));
 350     term->frontend = frontend;
 351     term->ucsdata = ucsdata;
 352     term->cfg = *mycfg;                /* STRUCTURE COPY */
 353     term->logctx = NULL;
 354     term->compatibility_level = TM_PUTTY;
 355     strcpy(term->id_string, "\033[?6c");
 356     term->last_blink = term->last_tblink = 0;
 357     term->paste_buffer = NULL;
 358     term->paste_len = 0;
 359     term->last_paste = 0;
 360     bufchain_init(&term->inbuf);
 361     bufchain_init(&term->printer_buf);
 362     term->printing = term->only_printing = FALSE;
 363     term->print_job = NULL;
 364     term->vt52_mode = FALSE;
 365     term->cr_lf_return = FALSE;
 366     term->seen_disp_event = FALSE;
 367     term->xterm_mouse = term->mouse_is_down = FALSE;
 368     term->reset_132 = FALSE;
 369     term->blinker = term->tblinker = 0;
 370     term->has_focus = 1;
 371     term->repeat_off = FALSE;
 372     term->termstate = TOPLEVEL;
 373     term->selstate = NO_SELECTION;
 374     term->curstype = 0;
 375
 376     term->screen = term->alt_screen = term->scrollback = NULL;
 377     term->disptop = 0;
 378     term->disptext = term->dispcurs = NULL;
 379     term->tabs = NULL;
 380     deselect(term);
 381     term->rows = term->cols = -1;
 382     power_on(term);
 383     term->beephead = term->beeptail = NULL;
 384     term->nbeeps = 0;
 385     term->lastbeep = FALSE;
 386     term->beep_overloaded = FALSE;
 387     term->attr_mask = 0xffffffff;
 388     term->resize_fn = NULL;
 389     term->resize_ctx = NULL;
 390
 391     return term;
 392 }
 393
 394 /*
 395  * Set up the terminal for a given size.
 396  */
 397 void term_size(Terminal *term, int newrows, int newcols, int newsavelines)
 398 {
 399     tree234 *newalt;
 400     unsigned long *newdisp, *line;
 401     int i, j;
 402     int sblen;
 403     int save_alt_which = term->alt_which;
 404
 405     if (newrows == term->rows && newcols == term->cols &&
 406         newsavelines == term->savelines)
 407         return;                        /* nothing to do */
 408
 409     deselect(term);
 410     swap_screen(term, 0, FALSE, FALSE);
 411
 412     term->alt_t = term->marg_t = 0;
 413     term->alt_b = term->marg_b = newrows - 1;
 414
 415     if (term->rows == -1) {
 416         term->scrollback = newtree234(NULL);
 417         term->screen = newtree234(NULL);
 418         term->rows = 0;
 419     }
 420
 421     /*
 422      * Resize the screen and scrollback. We only need to shift
 423      * lines around within our data structures, because lineptr()
 424      * will take care of resizing each individual line if
 425      * necessary. So:
 426      *
 427      *  - If the new screen and the old screen differ in length, we
 428      *    must shunt some lines in from the scrollback or out to
 429      *    the scrollback.
 430      *
 431      *  - If doing that fails to provide us with enough material to
 432      *    fill the new screen (i.e. the number of rows needed in
 433      *    the new screen exceeds the total number in the previous
 434      *    screen+scrollback), we must invent some blank lines to
 435      *    cover the gap.
 436      *
 437      *  - Then, if the new scrollback length is less than the
 438      *    amount of scrollback we actually have, we must throw some
 439      *    away.
 440      */
 441     sblen = count234(term->scrollback);
 442     /* Do this loop to expand the screen if newrows > rows */
 443     for (i = term->rows; i < newrows; i++) {
 444         if (sblen > 0) {
 445             line = delpos234(term->scrollback, --sblen);
 446         } else {
 447             line = smalloc(TSIZE * (newcols + 2));
 448             line[0] = newcols;
 449             for (j = 0; j <= newcols; j++)
 450                 line[j + 1] = ERASE_CHAR;
 451         }
 452         addpos234(term->screen, line, 0);
 453     }
 454     /* Do this loop to shrink the screen if newrows < rows */
 455     for (i = newrows; i < term->rows; i++) {
 456         line = delpos234(term->screen, 0);
 457         addpos234(term->scrollback, line, sblen++);
 458     }
 459     assert(count234(term->screen) == newrows);
 460     while (sblen > newsavelines) {
 461         line = delpos234(term->scrollback, 0);
 462         sfree(line);
 463         sblen--;
 464     }
 465     assert(count234(term->scrollback) <= newsavelines);
 466     term->disptop = 0;
 467
 468     newdisp = smalloc(newrows * (newcols + 1) * TSIZE);
 469     for (i = 0; i < newrows * (newcols + 1); i++)
 470         newdisp[i] = ATTR_INVALID;
 471     sfree(term->disptext);
 472     term->disptext = newdisp;
 473     term->dispcurs = NULL;
 474
 475     newalt = newtree234(NULL);
 476     for (i = 0; i < newrows; i++) {
 477         line = smalloc(TSIZE * (newcols + 2));
 478         line[0] = newcols;
 479         for (j = 0; j <= newcols; j++)
 480             line[j + 1] = term->erase_char;
 481         addpos234(newalt, line, i);
 482     }
 483     if (term->alt_screen) {
 484         while (NULL != (line = delpos234(term->alt_screen, 0)))
 485             sfree(line);
 486         freetree234(term->alt_screen);
 487     }
 488     term->alt_screen = newalt;
 489
 490     term->tabs = srealloc(term->tabs, newcols * sizeof(*term->tabs));
 491     {
 492         int i;
 493         for (i = (term->cols > 0 ? term->cols : 0); i < newcols; i++)
 494             term->tabs[i] = (i % 8 == 0 ? TRUE : FALSE);
 495     }
 496
 497     if (term->rows > 0)
 498         term->curs.y += newrows - term->rows;
 499     if (term->curs.y < 0)
 500         term->curs.y = 0;
 501     if (term->curs.y >= newrows)
 502         term->curs.y = newrows - 1;
 503     if (term->curs.x >= newcols)
 504         term->curs.x = newcols - 1;
 505     term->alt_x = term->alt_y = 0;
 506     term->wrapnext = term->alt_wnext = FALSE;
 507
 508     term->rows = newrows;
 509     term->cols = newcols;
 510     term->savelines = newsavelines;
 511     fix_cpos;
 512
 513     swap_screen(term, save_alt_which, FALSE, FALSE);
 514
 515     update_sbar(term);
 516     term_update(term);
 517     if (term->resize_fn)
 518         term->resize_fn(term->resize_ctx, term->cols, term->rows);
 519 }
 520
 521 /*
 522  * Hand a function and context pointer to the terminal which it can
 523  * use to notify a back end of resizes.
 524  */
 525 void term_provide_resize_fn(Terminal *term,
 526                             void (*resize_fn)(void *, int, int),
 527                             void *resize_ctx)
 528 {
 529     term->resize_fn = resize_fn;
 530     term->resize_ctx = resize_ctx;
 531     if (term->cols > 0 && term->rows > 0)
 532         resize_fn(resize_ctx, term->cols, term->rows);
 533 }
 534
 535 /*
 536  * Swap screens. If `reset' is TRUE and we have been asked to
 537  * switch to the alternate screen, we must bring most of its
 538  * configuration from the main screen and erase the contents of the
 539  * alternate screen completely. (This is even true if we're already
 540  * on it! Blame xterm.)
 541  */
 542 static void swap_screen(Terminal *term, int which, int reset, int keep_cur_pos)
 543 {
 544     int t;
 545     tree234 *ttr;
 546
 547     if (!which)
 548         reset = FALSE;                 /* do no weird resetting if which==0 */
 549
 550     if (which != term->alt_which) {
 551         term->alt_which = which;
 552
 553         ttr = term->alt_screen;
 554         term->alt_screen = term->screen;
 555         term->screen = ttr;
 556         t = term->curs.x;
 557         if (!reset && !keep_cur_pos)
 558             term->curs.x = term->alt_x;
 559         term->alt_x = t;
 560         t = term->curs.y;
 561         if (!reset && !keep_cur_pos)
 562             term->curs.y = term->alt_y;
 563         term->alt_y = t;
 564         t = term->marg_t;
 565         if (!reset) term->marg_t = term->alt_t;
 566         term->alt_t = t;
 567         t = term->marg_b;
 568         if (!reset) term->marg_b = term->alt_b;
 569         term->alt_b = t;
 570         t = term->dec_om;
 571         if (!reset) term->dec_om = term->alt_om;
 572         term->alt_om = t;
 573         t = term->wrap;
 574         if (!reset) term->wrap = term->alt_wrap;
 575         term->alt_wrap = t;
 576         t = term->wrapnext;
 577         if (!reset) term->wrapnext = term->alt_wnext;
 578         term->alt_wnext = t;
 579         t = term->insert;
 580         if (!reset) term->insert = term->alt_ins;
 581         term->alt_ins = t;
 582         t = term->cset;
 583         if (!reset) term->cset = term->alt_cset;
 584         term->alt_cset = t;
 585         t = term->utf;
 586         if (!reset) term->utf = term->alt_utf;
 587         term->alt_utf = t;
 588         t = term->sco_acs;
 589         if (!reset) term->sco_acs = term->alt_sco_acs;
 590         term->alt_sco_acs = t;
 591     }
 592
 593     if (reset && term->screen) {
 594         /*
 595          * Yes, this _is_ supposed to honour background-colour-erase.
 596          */
 597         erase_lots(term, FALSE, TRUE, TRUE);
 598     }
 599
 600     /*
 601      * This might not be possible if we're called during
 602      * initialisation.
 603      */
 604     if (term->screen)
 605         fix_cpos;
 606 }
 607
 608 /*
 609  * Update the scroll bar.
 610  */
 611 static void update_sbar(Terminal *term)
 612 {
 613     int nscroll;
 614
 615     nscroll = count234(term->scrollback);
 616
 617     set_sbar(term->frontend, nscroll + term->rows,
 618              nscroll + term->disptop, term->rows);
 619 }
 620
 621 /*
 622  * Check whether the region bounded by the two pointers intersects
 623  * the scroll region, and de-select the on-screen selection if so.
 624  */
 625 static void check_selection(Terminal *term, pos from, pos to)
 626 {
 627     if (poslt(from, term->selend) && poslt(term->selstart, to))
 628         deselect(term);
 629 }
 630
 631 /*
 632  * Scroll the screen. (`lines' is +ve for scrolling forward, -ve
 633  * for backward.) `sb' is TRUE if the scrolling is permitted to
 634  * affect the scrollback buffer.
 635  *
 636  * NB this function invalidates all pointers into lines of the
 637  * screen data structures. In particular, you MUST call fix_cpos
 638  * after calling scroll() and before doing anything else that
 639  * uses the cpos shortcut pointer.
 640  */
 641 static void scroll(Terminal *term, int topline, int botline, int lines, int sb)
 642 {
 643     unsigned long *line, *line2;
 644     int i, seltop, olddisptop, shift;
 645
 646     if (topline != 0 || term->alt_which != 0)
 647         sb = FALSE;
 648
 649     olddisptop = term->disptop;
 650     shift = lines;
 651     if (lines < 0) {
 652         while (lines < 0) {
 653             line = delpos234(term->screen, botline);
 654             line = resizeline(line, term->cols);
 655             for (i = 0; i < term->cols; i++)
 656                 line[i + 1] = term->erase_char;
 657             line[term->cols + 1] = 0;
 658             addpos234(term->screen, line, topline);
 659
 660             if (term->selstart.y >= topline && term->selstart.y <= botline) {
 661                 term->selstart.y++;
 662                 if (term->selstart.y > botline) {
 663                     term->selstart.y = botline;
 664                     term->selstart.x = 0;
 665                 }
 666             }
 667             if (term->selend.y >= topline && term->selend.y <= botline) {
 668                 term->selend.y++;
 669                 if (term->selend.y > botline) {
 670                     term->selend.y = botline;
 671                     term->selend.x = 0;
 672                 }
 673             }
 674
 675             lines++;
 676         }
 677     } else {
 678         while (lines > 0) {
 679             line = delpos234(term->screen, topline);
 680             if (sb && term->savelines > 0) {
 681                 int sblen = count234(term->scrollback);
 682                 /*
 683                  * We must add this line to the scrollback. We'll
 684                  * remove a line from the top of the scrollback to
 685                  * replace it, or allocate a new one if the
 686                  * scrollback isn't full.
 687                  */
 688                 if (sblen == term->savelines) {
 689                     sblen--, line2 = delpos234(term->scrollback, 0);
 690                 } else {
 691                     line2 = smalloc(TSIZE * (term->cols + 2));
 692                     line2[0] = term->cols;
 693                 }
 694                 addpos234(term->scrollback, line, sblen);
 695                 line = line2;
 696
 697                 /*
 698                  * If the user is currently looking at part of the
 699                  * scrollback, and they haven't enabled any options
 700                  * that are going to reset the scrollback as a
 701                  * result of this movement, then the chances are
 702                  * they'd like to keep looking at the same line. So
 703                  * we move their viewpoint at the same rate as the
 704                  * scroll, at least until their viewpoint hits the
 705                  * top end of the scrollback buffer, at which point
 706                  * we don't have the choice any more.
 707                  *
 708                  * Thanks to Jan Holmen Holsten for the idea and
 709                  * initial implementation.
 710                  */
 711                 if (term->disptop > -term->savelines && term->disptop < 0)
 712                     term->disptop--;
 713             }
 714             line = resizeline(line, term->cols);
 715             for (i = 0; i < term->cols; i++)
 716                 line[i + 1] = term->erase_char;
 717             line[term->cols + 1] = 0;
 718             addpos234(term->screen, line, botline);
 719
 720             /*
 721              * If the selection endpoints move into the scrollback,
 722              * we keep them moving until they hit the top. However,
 723              * of course, if the line _hasn't_ moved into the
 724              * scrollback then we don't do this, and cut them off
 725              * at the top of the scroll region.
 726              *
 727              * This applies to selstart and selend (for an existing
 728              * selection), and also selanchor (for one being
 729              * selected as we speak).
 730              */
 731             seltop = sb ? -term->savelines : topline;
 732
 733             if (term->selstart.y >= seltop &&
 734                 term->selstart.y <= botline) {
 735                 term->selstart.y--;
 736                 if (term->selstart.y < seltop) {
 737                     term->selstart.y = seltop;
 738                     term->selstart.x = 0;
 739                 }
 740             }
 741             if (term->selend.y >= seltop && term->selend.y <= botline) {
 742                 term->selend.y--;
 743                 if (term->selend.y < seltop) {
 744                     term->selend.y = seltop;
 745                     term->selend.x = 0;
 746                 }
 747             }
 748             if (term->selanchor.y >= seltop && term->selanchor.y <= botline) {
 749                 term->selanchor.y--;
 750                 if (term->selanchor.y < seltop) {
 751                     term->selanchor.y = seltop;
 752                     term->selanchor.x = 0;
 753                 }
 754             }
 755
 756             lines--;
 757         }
 758     }
 759 #ifdef OPTIMISE_SCROLL
 760     shift += term->disptop - olddisptop;
 761     if (shift < term->rows && shift > -term->rows && shift != 0)
 762         scroll_display(term, topline, botline, shift);
 763 #endif /* OPTIMISE_SCROLL */
 764 }
 765
 766 #ifdef OPTIMISE_SCROLL
 767 /*
 768  * Scroll the physical display, and our conception of it in disptext.
 769  */
 770 static void scroll_display(Terminal *term, int topline, int botline, int lines)
 771 {
 772     unsigned long *start, *end;
 773     int distance, size, i;
 774
 775     start = term->disptext + topline * (term->cols + 1);
 776     end = term->disptext + (botline + 1) * (term->cols + 1);
 777     distance = (lines > 0 ? lines : -lines) * (term->cols + 1);
 778     size = end - start - distance;
 779     if (lines > 0) {
 780         memmove(start, start + distance, size * TSIZE);
 781         if (term->dispcurs >= start + distance &&
 782             term->dispcurs <= start + distance + size)
 783             term->dispcurs -= distance;
 784         for (i = 0; i < distance; i++)
 785             (start + size)[i] |= ATTR_INVALID;
 786     } else {
 787         memmove(start + distance, start, size * TSIZE);
 788         if (term->dispcurs >= start && term->dispcurs <= start + size)
 789             term->dispcurs += distance;
 790         for (i = 0; i < distance; i++)
 791             start[i] |= ATTR_INVALID;
 792     }
 793     do_scroll(term->frontend, topline, botline, lines);
 794 }
 795 #endif /* OPTIMISE_SCROLL */
 796
 797 /*
 798  * Move the cursor to a given position, clipping at boundaries. We
 799  * may or may not want to clip at the scroll margin: marg_clip is 0
 800  * not to, 1 to disallow _passing_ the margins, and 2 to disallow
 801  * even _being_ outside the margins.
 802  */
 803 static void move(Terminal *term, int x, int y, int marg_clip)
 804 {
 805     if (x < 0)
 806         x = 0;
 807     if (x >= term->cols)
 808         x = term->cols - 1;
 809     if (marg_clip) {
 810         if ((term->curs.y >= term->marg_t || marg_clip == 2) &&
 811             y < term->marg_t)
 812             y = term->marg_t;
 813         if ((term->curs.y <= term->marg_b || marg_clip == 2) &&
 814             y > term->marg_b)
 815             y = term->marg_b;
 816     }
 817     if (y < 0)
 818         y = 0;
 819     if (y >= term->rows)
 820         y = term->rows - 1;
 821     term->curs.x = x;
 822     term->curs.y = y;
 823     fix_cpos;
 824     term->wrapnext = FALSE;
 825 }
 826
 827 /*
 828  * Save or restore the cursor and SGR mode.
 829  */
 830 static void save_cursor(Terminal *term, int save)
 831 {
 832     if (save) {
 833         term->savecurs = term->curs;
 834         term->save_attr = term->curr_attr;
 835         term->save_cset = term->cset;
 836         term->save_utf = term->utf;
 837         term->save_wnext = term->wrapnext;
 838         term->save_csattr = term->cset_attr[term->cset];
 839         term->save_sco_acs = term->sco_acs;
 840     } else {
 841         term->curs = term->savecurs;
 842         /* Make sure the window hasn't shrunk since the save */
 843         if (term->curs.x >= term->cols)
 844             term->curs.x = term->cols - 1;
 845         if (term->curs.y >= term->rows)
 846             term->curs.y = term->rows - 1;
 847
 848         term->curr_attr = term->save_attr;
 849         term->cset = term->save_cset;
 850         term->utf = term->save_utf;
 851         term->wrapnext = term->save_wnext;
 852         /*
 853          * wrapnext might reset to False if the x position is no
 854          * longer at the rightmost edge.
 855          */
 856         if (term->wrapnext && term->curs.x < term->cols-1)
 857             term->wrapnext = FALSE;
 858         term->cset_attr[term->cset] = term->save_csattr;
 859         term->sco_acs = term->save_sco_acs;
 860         fix_cpos;
 861         if (term->use_bce)
 862             term->erase_char = (' ' | ATTR_ASCII |
 863                                 (term->curr_attr &
 864                                  (ATTR_FGMASK | ATTR_BGMASK)));
 865     }
 866 }
 867
 868 /*
 869  * This function is called before doing _anything_ which affects
 870  * only part of a line of text. It is used to mark the boundary
 871  * between two character positions, and it indicates that some sort
 872  * of effect is going to happen on only one side of that boundary.
 873  *
 874  * The effect of this function is to check whether a CJK
 875  * double-width character is straddling the boundary, and to remove
 876  * it and replace it with two spaces if so. (Of course, one or
 877  * other of those spaces is then likely to be replaced with
 878  * something else again, as a result of whatever happens next.)
 879  *
 880  * Also, if the boundary is at the right-hand _edge_ of the screen,
 881  * it implies something deliberate is being done to the rightmost
 882  * column position; hence we must clear LATTR_WRAPPED2.
 883  *
 884  * The input to the function is the coordinates of the _second_
 885  * character of the pair.
 886  */
 887 static void check_boundary(Terminal *term, int x, int y)
 888 {
 889     unsigned long *ldata;
 890
 891     /* Validate input coordinates, just in case. */
 892     if (x == 0 || x > term->cols)
 893         return;
 894
 895     ldata = lineptr(y);
 896     if (x == term->cols) {
 897         ldata[x] &= ~LATTR_WRAPPED2;
 898     } else {
 899         if ((ldata[x] & (CHAR_MASK | CSET_MASK)) == UCSWIDE) {
 900             ldata[x-1] = ldata[x] =
 901                 (ldata[x-1] &~ (CHAR_MASK | CSET_MASK)) | ATTR_ASCII | ' ';
 902         }
 903     }
 904 }
 905
 906 /*
 907  * Erase a large portion of the screen: the whole screen, or the
 908  * whole line, or parts thereof.
 909  */
 910 static void erase_lots(Terminal *term,
 911                        int line_only, int from_begin, int to_end)
 912 {
 913     pos start, end;
 914     int erase_lattr;
 915     unsigned long *ldata;
 916
 917     if (line_only) {
 918         start.y = term->curs.y;
 919         start.x = 0;
 920         end.y = term->curs.y + 1;
 921         end.x = 0;
 922         erase_lattr = FALSE;
 923     } else {
 924         start.y = 0;
 925         start.x = 0;
 926         end.y = term->rows;
 927         end.x = 0;
 928         erase_lattr = TRUE;
 929     }
 930     if (!from_begin) {
 931         start = term->curs;
 932     }
 933     if (!to_end) {
 934         end = term->curs;
 935         incpos(end);
 936     }
 937     if (!from_begin || !to_end)
 938         check_boundary(term, term->curs.x, term->curs.y);
 939     check_selection(term, start, end);
 940
 941     /* Clear screen also forces a full window redraw, just in case. */
 942     if (start.y == 0 && start.x == 0 && end.y == term->rows)
 943         term_invalidate(term);
 944
 945     ldata = lineptr(start.y);
 946     while (poslt(start, end)) {
 947         if (start.x == term->cols && !erase_lattr)
 948             ldata[start.x] &= ~(LATTR_WRAPPED | LATTR_WRAPPED2);
 949         else
 950             ldata[start.x] = term->erase_char;
 951         if (incpos(start) && start.y < term->rows)
 952             ldata = lineptr(start.y);
 953     }
 954 }
 955
 956 /*
 957  * Insert or delete characters within the current line. n is +ve if
 958  * insertion is desired, and -ve for deletion.
 959  */
 960 static void insch(Terminal *term, int n)
 961 {
 962     int dir = (n < 0 ? -1 : +1);
 963     int m;
 964     pos cursplus;
 965     unsigned long *ldata;
 966
 967     n = (n < 0 ? -n : n);
 968     if (n > term->cols - term->curs.x)
 969         n = term->cols - term->curs.x;
 970     m = term->cols - term->curs.x - n;
 971     cursplus.y = term->curs.y;
 972     cursplus.x = term->curs.x + n;
 973     check_selection(term, term->curs, cursplus);
 974     check_boundary(term, term->curs.x, term->curs.y);
 975     if (dir < 0)
 976         check_boundary(term, term->curs.x + n, term->curs.y);
 977     ldata = lineptr(term->curs.y);
 978     if (dir < 0) {
 979         memmove(ldata + term->curs.x, ldata + term->curs.x + n, m * TSIZE);
 980         while (n--)
 981             ldata[term->curs.x + m++] = term->erase_char;
 982     } else {
 983         memmove(ldata + term->curs.x + n, ldata + term->curs.x, m * TSIZE);
 984         while (n--)
 985             ldata[term->curs.x + n] = term->erase_char;
 986     }
 987 }
 988
 989 /*
 990  * Toggle terminal mode `mode' to state `state'. (`query' indicates
 991  * whether the mode is a DEC private one or a normal one.)
 992  */
 993 static void toggle_mode(Terminal *term, int mode, int query, int state)
 994 {
 995     unsigned long ticks;
 996
 997     if (query)
 998         switch (mode) {
 999           case 1:                      /* application cursor keys */
1000             term->app_cursor_keys = state;
1001             break;
1002           case 2:                      /* VT52 mode */
1003             term->vt52_mode = !state;
1004             if (term->vt52_mode) {
1005                 term->blink_is_real = FALSE;
1006                 term->vt52_bold = FALSE;
1007             } else {
1008                 term->blink_is_real = term->cfg.blinktext;
1009             }
1010             break;
1011           case 3:                      /* 80/132 columns */
1012             deselect(term);
1013             if (!term->cfg.no_remote_resize)
1014                 request_resize(term->frontend, state ? 132 : 80, term->rows);
1015             term->reset_132 = state;
1016             break;
1017           case 5:                      /* reverse video */
1018             /*
1019              * Toggle reverse video. If we receive an OFF within the
1020              * visual bell timeout period after an ON, we trigger an
1021              * effective visual bell, so that ESC[?5hESC[?5l will
1022              * always be an actually _visible_ visual bell.
1023              */
1024             ticks = GETTICKCOUNT();
1025             /* turn off a previous vbell to avoid inconsistencies */
1026             if (ticks - term->vbell_startpoint >= VBELL_TIMEOUT)
1027                 term->in_vbell = FALSE;
1028             if (term->rvideo && !state &&    /* we're turning it off... */
1029                 (ticks - term->rvbell_startpoint) < VBELL_TIMEOUT) {/*...soon*/
1030                 /* If there's no vbell timeout already, or this one lasts
1031                  * longer, replace vbell_timeout with ours. */
1032                 if (!term->in_vbell ||
1033                     (term->rvbell_startpoint - term->vbell_startpoint <
1034                      VBELL_TIMEOUT))
1035                     term->vbell_startpoint = term->rvbell_startpoint;
1036                 term->in_vbell = TRUE; /* may clear rvideo but set in_vbell */
1037             } else if (!term->rvideo && state) {
1038                 /* This is an ON, so we notice the time and save it. */
1039                 term->rvbell_startpoint = ticks;
1040             }
1041             term->rvideo = state;
1042             term->seen_disp_event = TRUE;
1043             if (state)
1044                 term_update(term);
1045             break;
1046           case 6:                      /* DEC origin mode */
1047             term->dec_om = state;
1048             break;
1049           case 7:                      /* auto wrap */
1050             term->wrap = state;
1051             break;
1052           case 8:                      /* auto key repeat */
1053             term->repeat_off = !state;
1054             break;
1055           case 10:                     /* set local edit mode */
1056             term->term_editing = state;
1057             if (term->ldisc)           /* cause ldisc to notice changes */
1058                 ldisc_send(term->ldisc, NULL, 0, 0);
1059             break;
1060           case 25:                     /* enable/disable cursor */
1061             compatibility2(OTHER, VT220);
1062             term->cursor_on = state;
1063             term->seen_disp_event = TRUE;
1064             break;
1065           case 47:                     /* alternate screen */
1066             compatibility(OTHER);
1067             deselect(term);
1068             swap_screen(term, term->cfg.no_alt_screen ? 0 : state, FALSE, FALSE);
1069             term->disptop = 0;
1070             break;
1071           case 1000:                   /* xterm mouse 1 */
1072             term->xterm_mouse = state ? 1 : 0;
1073             set_raw_mouse_mode(term->frontend, state);
1074             break;
1075           case 1002:                   /* xterm mouse 2 */
1076             term->xterm_mouse = state ? 2 : 0;
1077             set_raw_mouse_mode(term->frontend, state);
1078             break;
1079           case 1047:                   /* alternate screen */
1080             compatibility(OTHER);
1081             deselect(term);
1082             swap_screen(term, term->cfg.no_alt_screen ? 0 : state, TRUE, TRUE);
1083             term->disptop = 0;
1084             break;
1085           case 1048:                   /* save/restore cursor */
1086             save_cursor(term, state);
1087             if (!state) term->seen_disp_event = TRUE;
1088             break;
1089           case 1049:                   /* cursor & alternate screen */
1090             if (state)
1091                 save_cursor(term, state);
1092             if (!state) term->seen_disp_event = TRUE;
1093             compatibility(OTHER);
1094             deselect(term);
1095             swap_screen(term, term->cfg.no_alt_screen ? 0 : state, TRUE, FALSE);
1096             if (!state)
1097                 save_cursor(term, state);
1098             term->disptop = 0;
1099             break;
1100     } else
1101         switch (mode) {
1102           case 4:                      /* set insert mode */
1103             compatibility(VT102);
1104             term->insert = state;
1105             break;
1106           case 12:                     /* set echo mode */
1107             term->term_echoing = !state;
1108             if (term->ldisc)           /* cause ldisc to notice changes */
1109                 ldisc_send(term->ldisc, NULL, 0, 0);
1110             break;
1111           case 20:                     /* Return sends ... */
1112             term->cr_lf_return = state;
1113             break;
1114           case 34:                     /* Make cursor BIG */
1115             compatibility2(OTHER, VT220);
1116             term->big_cursor = !state;
1117         }
1118 }
1119
1120 /*
1121  * Process an OSC sequence: set window title or icon name.
1122  */
1123 static void do_osc(Terminal *term)
1124 {
1125     if (term->osc_w) {
1126         while (term->osc_strlen--)
1127             term->wordness[(unsigned char)
1128                 term->osc_string[term->osc_strlen]] = term->esc_args[0];
1129     } else {
1130         term->osc_string[term->osc_strlen] = '\0';
1131         switch (term->esc_args[0]) {
1132           case 0:
1133           case 1:
1134             if (!term->cfg.no_remote_wintitle)
1135                 set_icon(term->frontend, term->osc_string);
1136             if (term->esc_args[0] == 1)
1137                 break;
1138             /* fall through: parameter 0 means set both */
1139           case 2:
1140           case 21:
1141             if (!term->cfg.no_remote_wintitle)
1142                 set_title(term->frontend, term->osc_string);
1143             break;
1144         }
1145     }
1146 }
1147
1148 /*
1149  * ANSI printing routines.
1150  */
1151 static void term_print_setup(Terminal *term)
1152 {
1153     bufchain_clear(&term->printer_buf);
1154     term->print_job = printer_start_job(term->cfg.printer);
1155 }
1156 static void term_print_flush(Terminal *term)
1157 {
1158     void *data;
1159     int len;
1160     int size;
1161     while ((size = bufchain_size(&term->printer_buf)) > 5) {
1162         bufchain_prefix(&term->printer_buf, &data, &len);
1163         if (len > size-5)
1164             len = size-5;
1165         printer_job_data(term->print_job, data, len);
1166         bufchain_consume(&term->printer_buf, len);
1167     }
1168 }
1169 static void term_print_finish(Terminal *term)
1170 {
1171     void *data;
1172     int len, size;
1173     char c;
1174
1175     if (!term->printing && !term->only_printing)
1176         return;                        /* we need do nothing */
1177
1178     term_print_flush(term);
1179     while ((size = bufchain_size(&term->printer_buf)) > 0) {
1180         bufchain_prefix(&term->printer_buf, &data, &len);
1181         c = *(char *)data;
1182         if (c == '\033' || c == '\233') {
1183             bufchain_consume(&term->printer_buf, size);
1184             break;
1185         } else {
1186             printer_job_data(term->print_job, &c, 1);
1187             bufchain_consume(&term->printer_buf, 1);
1188         }
1189     }
1190     printer_finish_job(term->print_job);
1191     term->print_job = NULL;
1192     term->printing = term->only_printing = FALSE;
1193 }
1194
1195 /*
1196  * Remove everything currently in `inbuf' and stick it up on the
1197  * in-memory display. There's a big state machine in here to
1198  * process escape sequences...
1199  */
1200 void term_out(Terminal *term)
1201 {
1202     int c, unget;
1203     unsigned char localbuf[256], *chars;
1204     int nchars = 0;
1205
1206     unget = -1;
1207
1208     chars = NULL;                      /* placate compiler warnings */
1209     while (nchars > 0 || bufchain_size(&term->inbuf) > 0) {
1210         if (unget == -1) {
1211             if (nchars == 0) {
1212                 void *ret;
1213                 bufchain_prefix(&term->inbuf, &ret, &nchars);
1214                 if (nchars > sizeof(localbuf))
1215                     nchars = sizeof(localbuf);
1216                 memcpy(localbuf, ret, nchars);
1217                 bufchain_consume(&term->inbuf, nchars);
1218                 chars = localbuf;
1219                 assert(chars != NULL);
1220             }
1221             c = *chars++;
1222             nchars--;
1223
1224             /*
1225              * Optionally log the session traffic to a file. Useful for
1226              * debugging and possibly also useful for actual logging.
1227              */
1228             if (term->cfg.logtype == LGTYP_DEBUG && term->logctx)
1229                 logtraffic(term->logctx, (unsigned char) c, LGTYP_DEBUG);
1230         } else {
1231             c = unget;
1232             unget = -1;
1233         }
1234
1235         /* Note only VT220+ are 8-bit VT102 is seven bit, it shouldn't even
1236          * be able to display 8-bit characters, but I'll let that go 'cause
1237          * of i18n.
1238          */
1239
1240         /*
1241          * If we're printing, add the character to the printer
1242          * buffer.
1243          */
1244         if (term->printing) {
1245             bufchain_add(&term->printer_buf, &c, 1);
1246
1247             /*
1248              * If we're in print-only mode, we use a much simpler
1249              * state machine designed only to recognise the ESC[4i
1250              * termination sequence.
1251              */
1252             if (term->only_printing) {
1253                 if (c == '\033')
1254                     term->print_state = 1;
1255                 else if (c == (unsigned char)'\233')
1256                     term->print_state = 2;
1257                 else if (c == '[' && term->print_state == 1)
1258                     term->print_state = 2;
1259                 else if (c == '4' && term->print_state == 2)
1260                     term->print_state = 3;
1261                 else if (c == 'i' && term->print_state == 3)
1262                     term->print_state = 4;
1263                 else
1264                     term->print_state = 0;
1265                 if (term->print_state == 4) {
1266                     term_print_finish(term);
1267                 }
1268                 continue;
1269             }
1270         }
1271
1272         /* First see about all those translations. */
1273         if (term->termstate == TOPLEVEL) {
1274             if (in_utf(term))
1275                 switch (term->utf_state) {
1276                   case 0:
1277                     if (c < 0x80) {
1278                         /* UTF-8 must be stateless so we ignore iso2022. */
1279                         if (term->ucsdata->unitab_ctrl[c] != 0xFF)
1280                              c = term->ucsdata->unitab_ctrl[c];
1281                         else c = ((unsigned char)c) | ATTR_ASCII;
1282                         break;
1283                     } else if ((c & 0xe0) == 0xc0) {
1284                         term->utf_size = term->utf_state = 1;
1285                         term->utf_char = (c & 0x1f);
1286                     } else if ((c & 0xf0) == 0xe0) {
1287                         term->utf_size = term->utf_state = 2;
1288                         term->utf_char = (c & 0x0f);
1289                     } else if ((c & 0xf8) == 0xf0) {
1290                         term->utf_size = term->utf_state = 3;
1291                         term->utf_char = (c & 0x07);
1292                     } else if ((c & 0xfc) == 0xf8) {
1293                         term->utf_size = term->utf_state = 4;
1294                         term->utf_char = (c & 0x03);
1295                     } else if ((c & 0xfe) == 0xfc) {
1296                         term->utf_size = term->utf_state = 5;
1297                         term->utf_char = (c & 0x01);
1298                     } else {
1299                         c = UCSERR;
1300                         break;
1301                     }
1302                     continue;
1303                   case 1:
1304                   case 2:
1305                   case 3:
1306                   case 4:
1307                   case 5:
1308                     if ((c & 0xC0) != 0x80) {
1309                         unget = c;
1310                         c = UCSERR;
1311                         term->utf_state = 0;
1312                         break;
1313                     }
1314                     term->utf_char = (term->utf_char << 6) | (c & 0x3f);
1315                     if (--term->utf_state)
1316                         continue;
1317
1318                     c = term->utf_char;
1319
1320                     /* Is somebody trying to be evil! */
1321                     if (c < 0x80 ||
1322                         (c < 0x800 && term->utf_size >= 2) ||
1323                         (c < 0x10000 && term->utf_size >= 3) ||
1324                         (c < 0x200000 && term->utf_size >= 4) ||
1325                         (c < 0x4000000 && term->utf_size >= 5))
1326                         c = UCSERR;
1327
1328                     /* Unicode line separator and paragraph separator are CR-LF */
1329                     if (c == 0x2028 || c == 0x2029)
1330                         c = 0x85;
1331
1332                     /* High controls are probably a Baaad idea too. */
1333                     if (c < 0xA0)
1334                         c = 0xFFFD;
1335
1336                     /* The UTF-16 surrogates are not nice either. */
1337                     /*       The standard give the option of decoding these:
1338                      *       I don't want to! */
1339                     if (c >= 0xD800 && c < 0xE000)
1340                         c = UCSERR;
1341
1342                     /* ISO 10646 characters now limited to UTF-16 range. */
1343                     if (c > 0x10FFFF)
1344                         c = UCSERR;
1345
1346                     /* This is currently a TagPhobic application.. */
1347                     if (c >= 0xE0000 && c <= 0xE007F)
1348                         continue;
1349
1350                     /* U+FEFF is best seen as a null. */
1351                     if (c == 0xFEFF)
1352                         continue;
1353                     /* But U+FFFE is an error. */
1354                     if (c == 0xFFFE || c == 0xFFFF)
1355                         c = UCSERR;
1356
1357                     /* Oops this is a 16bit implementation */
1358                     if (c >= 0x10000)
1359                         c = 0xFFFD;
1360                     break;
1361             }
1362             /* Are we in the nasty ACS mode? Note: no sco in utf mode. */
1363             else if(term->sco_acs &&
1364                     (c!='\033' && c!='\012' && c!='\015' && c!='\b'))
1365             {
1366                if (term->sco_acs == 2) c |= 0x80;
1367                c |= ATTR_SCOACS;
1368             } else {
1369                 switch (term->cset_attr[term->cset]) {
1370                     /*
1371                      * Linedraw characters are different from 'ESC ( B'
1372                      * only for a small range. For ones outside that
1373                      * range, make sure we use the same font as well as
1374                      * the same encoding.
1375                      */
1376                   case ATTR_LINEDRW:
1377                     if (term->ucsdata->unitab_ctrl[c] != 0xFF)
1378                         c = term->ucsdata->unitab_ctrl[c];
1379                     else
1380                         c = ((unsigned char) c) | ATTR_LINEDRW;
1381                     break;
1382
1383                   case ATTR_GBCHR:
1384                     /* If UK-ASCII, make the '#' a LineDraw Pound */
1385                     if (c == '#') {
1386                         c = '}' | ATTR_LINEDRW;
1387                         break;
1388                     }
1389                   /*FALLTHROUGH*/ case ATTR_ASCII:
1390                     if (term->ucsdata->unitab_ctrl[c] != 0xFF)
1391                         c = term->ucsdata->unitab_ctrl[c];
1392                     else
1393                         c = ((unsigned char) c) | ATTR_ASCII;
1394                     break;
1395                 case ATTR_SCOACS:
1396                     if (c>=' ') c = ((unsigned char)c) | ATTR_SCOACS;
1397                     break;
1398                 }
1399             }
1400         }
1401
1402         /* How about C1 controls ? */
1403         if ((c & -32) == 0x80 && term->termstate < DO_CTRLS &&
1404             !term->vt52_mode && has_compat(VT220)) {
1405             term->termstate = SEEN_ESC;
1406             term->esc_query = FALSE;
1407             c = '@' + (c & 0x1F);
1408         }
1409
1410         /* Or the GL control. */
1411         if (c == '\177' && term->termstate < DO_CTRLS && has_compat(OTHER)) {
1412             if (term->curs.x && !term->wrapnext)
1413                 term->curs.x--;
1414             term->wrapnext = FALSE;
1415             fix_cpos;
1416             if (!term->cfg.no_dbackspace)    /* destructive bksp might be disabled */
1417                 *term->cpos = (' ' | term->curr_attr | ATTR_ASCII);
1418         } else
1419             /* Or normal C0 controls. */
1420         if ((c & -32) == 0 && term->termstate < DO_CTRLS) {
1421             switch (c) {
1422               case '\005':             /* terminal type query */
1423                 /* Strictly speaking this is VT100 but a VT100 defaults to
1424                  * no response. Other terminals respond at their option.
1425                  *
1426                  * Don't put a CR in the default string as this tends to
1427                  * upset some weird software.
1428                  *
1429                  * An xterm returns "xterm" (5 characters)
1430                  */
1431                 compatibility(ANSIMIN);
1432                 if (term->ldisc) {
1433                     char abuf[256], *s, *d;
1434                     int state = 0;
1435                     for (s = term->cfg.answerback, d = abuf; *s; s++) {
1436                         if (state) {
1437                             if (*s >= 'a' && *s <= 'z')
1438                                 *d++ = (*s - ('a' - 1));
1439                             else if ((*s >= '@' && *s <= '_') ||
1440                                      *s == '?' || (*s & 0x80))
1441                                 *d++ = ('@' ^ *s);
1442                             else if (*s == '~')
1443                                 *d++ = '^';
1444                             state = 0;
1445                         } else if (*s == '^') {
1446                             state = 1;
1447                         } else
1448                             *d++ = *s;
1449                     }
1450                     lpage_send(term->ldisc, DEFAULT_CODEPAGE,
1451                                abuf, d - abuf, 0);
1452                 }
1453                 break;
1454               case '\007':
1455                 {
1456                     struct beeptime *newbeep;
1457                     unsigned long ticks;
1458
1459                     ticks = GETTICKCOUNT();
1460
1461                     if (!term->beep_overloaded) {
1462                         newbeep = smalloc(sizeof(struct beeptime));
1463                         newbeep->ticks = ticks;
1464                         newbeep->next = NULL;
1465                         if (!term->beephead)
1466                             term->beephead = newbeep;
1467                         else
1468                             term->beeptail->next = newbeep;
1469                         term->beeptail = newbeep;
1470                         term->nbeeps++;
1471                     }
1472
1473                     /*
1474                      * Throw out any beeps that happened more than
1475                      * t seconds ago.
1476                      */
1477                     while (term->beephead &&
1478                            term->beephead->ticks < ticks - term->cfg.bellovl_t) {
1479                         struct beeptime *tmp = term->beephead;
1480                         term->beephead = tmp->next;
1481                         sfree(tmp);
1482                         if (!term->beephead)
1483                             term->beeptail = NULL;
1484                         term->nbeeps--;
1485                     }
1486
1487                     if (term->cfg.bellovl && term->beep_overloaded &&
1488                         ticks - term->lastbeep >= (unsigned)term->cfg.bellovl_s) {
1489                         /*
1490                          * If we're currently overloaded and the
1491                          * last beep was more than s seconds ago,
1492                          * leave overload mode.
1493                          */
1494                         term->beep_overloaded = FALSE;
1495                     } else if (term->cfg.bellovl && !term->beep_overloaded &&
1496                                term->nbeeps >= term->cfg.bellovl_n) {
1497                         /*
1498                          * Now, if we have n or more beeps
1499                          * remaining in the queue, go into overload
1500                          * mode.
1501                          */
1502                         term->beep_overloaded = TRUE;
1503                     }
1504                     term->lastbeep = ticks;
1505
1506                     /*
1507                      * Perform an actual beep if we're not overloaded.
1508                      */
1509                     if (!term->cfg.bellovl || !term->beep_overloaded) {
1510                         beep(term->frontend, term->cfg.beep);
1511                         if (term->cfg.beep == BELL_VISUAL) {
1512                             term->in_vbell = TRUE;
1513                             term->vbell_startpoint = ticks;
1514                             term_update(term);
1515                         }
1516                     }
1517                     term->disptop = 0;
1518                 }
1519                 break;
1520               case '\b':
1521                 if (term->curs.x == 0 &&
1522                     (term->curs.y == 0 || term->wrap == 0))
1523                     /* do nothing */ ;
1524                 else if (term->curs.x == 0 && term->curs.y > 0)
1525                     term->curs.x = term->cols - 1, term->curs.y--;
1526                 else if (term->wrapnext)
1527                     term->wrapnext = FALSE;
1528                 else
1529                     term->curs.x--;
1530                 fix_cpos;
1531                 term->seen_disp_event = TRUE;
1532                 break;
1533               case '\016':
1534                 compatibility(VT100);
1535                 term->cset = 1;
1536                 break;
1537               case '\017':
1538                 compatibility(VT100);
1539                 term->cset = 0;
1540                 break;
1541               case '\033':
1542                 if (term->vt52_mode)
1543                     term->termstate = VT52_ESC;
1544                 else {
1545                     compatibility(ANSIMIN);
1546                     term->termstate = SEEN_ESC;
1547                     term->esc_query = FALSE;
1548                 }
1549                 break;
1550               case '\015':
1551                 term->curs.x = 0;
1552                 term->wrapnext = FALSE;
1553                 fix_cpos;
1554                 term->seen_disp_event = TRUE;
1555                 term->paste_hold = 0;
1556                 if (term->logctx)
1557                     logtraffic(term->logctx, (unsigned char) c, LGTYP_ASCII);
1558                 break;
1559               case '\014':
1560                 if (has_compat(SCOANSI)) {
1561                     move(term, 0, 0, 0);
1562                     erase_lots(term, FALSE, FALSE, TRUE);
1563                     term->disptop = 0;
1564                     term->wrapnext = FALSE;
1565                     term->seen_disp_event = 1;
1566                     break;
1567                 }
1568               case '\013':
1569                 compatibility(VT100);
1570               case '\012':
1571                 if (term->curs.y == term->marg_b)
1572                     scroll(term, term->marg_t, term->marg_b, 1, TRUE);
1573                 else if (term->curs.y < term->rows - 1)
1574                     term->curs.y++;
1575                 if (term->cfg.lfhascr)
1576                     term->curs.x = 0;
1577                 fix_cpos;
1578                 term->wrapnext = FALSE;
1579                 term->seen_disp_event = 1;
1580                 term->paste_hold = 0;
1581                 if (term->logctx)
1582                     logtraffic(term->logctx, (unsigned char) c, LGTYP_ASCII);
1583                 break;
1584               case '\t':
1585                 {
1586                     pos old_curs = term->curs;
1587                     unsigned long *ldata = lineptr(term->curs.y);
1588
1589                     do {
1590                         term->curs.x++;
1591                     } while (term->curs.x < term->cols - 1 &&
1592                              !term->tabs[term->curs.x]);
1593
1594                     if ((ldata[term->cols] & LATTR_MODE) != LATTR_NORM) {
1595                         if (term->curs.x >= term->cols / 2)
1596                             term->curs.x = term->cols / 2 - 1;
1597                     } else {
1598                         if (term->curs.x >= term->cols)
1599                             term->curs.x = term->cols - 1;
1600                     }
1601
1602                     fix_cpos;
1603                     check_selection(term, old_curs, term->curs);
1604                 }
1605                 term->seen_disp_event = TRUE;
1606                 break;
1607             }
1608         } else
1609             switch (term->termstate) {
1610               case TOPLEVEL:
1611                 /* Only graphic characters get this far;
1612                  * ctrls are stripped above */
1613                 if (term->wrapnext && term->wrap) {
1614                     term->cpos[1] |= LATTR_WRAPPED;
1615                     if (term->curs.y == term->marg_b)
1616                         scroll(term, term->marg_t, term->marg_b, 1, TRUE);
1617                     else if (term->curs.y < term->rows - 1)
1618                         term->curs.y++;
1619                     term->curs.x = 0;
1620                     fix_cpos;
1621                     term->wrapnext = FALSE;
1622                 }
1623                 if (term->insert)
1624                     insch(term, 1);
1625                 if (term->selstate != NO_SELECTION) {
1626                     pos cursplus = term->curs;
1627                     incpos(cursplus);
1628                     check_selection(term, term->curs, cursplus);
1629                 }
1630                 if (((c & CSET_MASK) == ATTR_ASCII || (c & CSET_MASK) == 0) &&
1631                     term->logctx)
1632                     logtraffic(term->logctx, (unsigned char) c, LGTYP_ASCII);
1633                 {
1634                     int width = 0;
1635                     if (DIRECT_CHAR(c))
1636                         width = 1;
1637                     if (!width)
1638                         width = wcwidth((wchar_t) c);
1639                     switch (width) {
1640                       case 2:
1641                         /*
1642                          * If we're about to display a double-width
1643                          * character starting in the rightmost
1644                          * column, then we do something special
1645                          * instead. We must print a space in the
1646                          * last column of the screen, then wrap;
1647                          * and we also set LATTR_WRAPPED2 which
1648                          * instructs subsequent cut-and-pasting not
1649                          * only to splice this line to the one
1650                          * after it, but to ignore the space in the
1651                          * last character position as well.
1652                          * (Because what was actually output to the
1653                          * terminal was presumably just a sequence
1654                          * of CJK characters, and we don't want a
1655                          * space to be pasted in the middle of
1656                          * those just because they had the
1657                          * misfortune to start in the wrong parity
1658                          * column. xterm concurs.)
1659                          */
1660                         check_boundary(term, term->curs.x, term->curs.y);
1661                         check_boundary(term, term->curs.x+2, term->curs.y);
1662                         if (term->curs.x == term->cols-1) {
1663                             *term->cpos++ = ATTR_ASCII | ' ' | term->curr_attr;
1664                             *term->cpos |= LATTR_WRAPPED | LATTR_WRAPPED2;
1665                             if (term->curs.y == term->marg_b)
1666                                 scroll(term, term->marg_t, term->marg_b,
1667                                        1, TRUE);
1668                             else if (term->curs.y < term->rows - 1)
1669                                 term->curs.y++;
1670                             term->curs.x = 0;
1671                             fix_cpos;
1672                             /* Now we must check_boundary again, of course. */
1673                             check_boundary(term, term->curs.x, term->curs.y);
1674                             check_boundary(term, term->curs.x+2, term->curs.y);
1675                         }
1676                         *term->cpos++ = c | term->curr_attr;
1677                         *term->cpos++ = UCSWIDE | term->curr_attr;
1678                         term->curs.x++;
1679                         break;
1680                       case 1:
1681                         check_boundary(term, term->curs.x, term->curs.y);
1682                         check_boundary(term, term->curs.x+1, term->curs.y);
1683                         *term->cpos++ = c | term->curr_attr;
1684                         break;
1685                       default:
1686                         continue;
1687                     }
1688                 }
1689                 term->curs.x++;
1690                 if (term->curs.x == term->cols) {
1691                     term->cpos--;
1692                     term->curs.x--;
1693                     term->wrapnext = TRUE;
1694                     if (term->wrap && term->vt52_mode) {
1695                         term->cpos[1] |= LATTR_WRAPPED;
1696                         if (term->curs.y == term->marg_b)
1697                             scroll(term, term->marg_t, term->marg_b, 1, TRUE);
1698                         else if (term->curs.y < term->rows - 1)
1699                             term->curs.y++;
1700                         term->curs.x = 0;
1701                         fix_cpos;
1702                         term->wrapnext = FALSE;
1703                     }
1704                 }
1705                 term->seen_disp_event = 1;
1706                 break;
1707
1708               case OSC_MAYBE_ST:
1709                 /*
1710                  * This state is virtually identical to SEEN_ESC, with the
1711                  * exception that we have an OSC sequence in the pipeline,
1712                  * and _if_ we see a backslash, we process it.
1713                  */
1714                 if (c == '\\') {
1715                     do_osc(term);
1716                     term->termstate = TOPLEVEL;
1717                     break;
1718                 }
1719                 /* else fall through */
1720               case SEEN_ESC:
1721                 if (c >= ' ' && c <= '/') {
1722                     if (term->esc_query)
1723                         term->esc_query = -1;
1724                     else
1725                         term->esc_query = c;
1726                     break;
1727                 }
1728                 term->termstate = TOPLEVEL;
1729                 switch (ANSI(c, term->esc_query)) {
1730                   case '[':            /* enter CSI mode */
1731                     term->termstate = SEEN_CSI;
1732                     term->esc_nargs = 1;
1733                     term->esc_args[0] = ARG_DEFAULT;
1734                     term->esc_query = FALSE;
1735                     break;
1736                   case ']':            /* xterm escape sequences */
1737                     /* Compatibility is nasty here, xterm, linux, decterm yuk! */
1738                     compatibility(OTHER);
1739                     term->termstate = SEEN_OSC;
1740                     term->esc_args[0] = 0;
1741                     break;
1742                   case '7':            /* save cursor */
1743                     compatibility(VT100);
1744                     save_cursor(term, TRUE);
1745                     break;
1746                   case '8':            /* restore cursor */
1747                     compatibility(VT100);
1748                     save_cursor(term, FALSE);
1749                     term->seen_disp_event = TRUE;
1750                     break;
1751                   case '=':
1752                     compatibility(VT100);
1753                     term->app_keypad_keys = TRUE;
1754                     break;
1755                   case '>':
1756                     compatibility(VT100);
1757                     term->app_keypad_keys = FALSE;
1758                     break;
1759                   case 'D':            /* exactly equivalent to LF */
1760                     compatibility(VT100);
1761                     if (term->curs.y == term->marg_b)
1762                         scroll(term, term->marg_t, term->marg_b, 1, TRUE);
1763                     else if (term->curs.y < term->rows - 1)
1764                         term->curs.y++;
1765                     fix_cpos;
1766                     term->wrapnext = FALSE;
1767                     term->seen_disp_event = TRUE;
1768                     break;
1769                   case 'E':            /* exactly equivalent to CR-LF */
1770                     compatibility(VT100);
1771                     term->curs.x = 0;
1772                     if (term->curs.y == term->marg_b)
1773                         scroll(term, term->marg_t, term->marg_b, 1, TRUE);
1774                     else if (term->curs.y < term->rows - 1)
1775                         term->curs.y++;
1776                     fix_cpos;
1777                     term->wrapnext = FALSE;
1778                     term->seen_disp_event = TRUE;
1779                     break;
1780                   case 'M':            /* reverse index - backwards LF */
1781                     compatibility(VT100);
1782                     if (term->curs.y == term->marg_t)
1783                         scroll(term, term->marg_t, term->marg_b, -1, TRUE);
1784                     else if (term->curs.y > 0)
1785                         term->curs.y--;
1786                     fix_cpos;
1787                     term->wrapnext = FALSE;
1788                     term->seen_disp_event = TRUE;
1789                     break;
1790                   case 'Z':            /* terminal type query */
1791                     compatibility(VT100);
1792                     if (term->ldisc)
1793                         ldisc_send(term->ldisc, term->id_string,
1794                                    strlen(term->id_string), 0);
1795                     break;
1796                   case 'c':            /* restore power-on settings */
1797                     compatibility(VT100);
1798                     power_on(term);
1799                     if (term->ldisc)   /* cause ldisc to notice changes */
1800                         ldisc_send(term->ldisc, NULL, 0, 0);
1801                     if (term->reset_132) {
1802                         if (!term->cfg.no_remote_resize)
1803                             request_resize(term->frontend, 80, term->rows);
1804                         term->reset_132 = 0;
1805                     }
1806                     fix_cpos;
1807                     term->disptop = 0;
1808                     term->seen_disp_event = TRUE;
1809                     break;
1810                   case 'H':            /* set a tab */
1811                     compatibility(VT100);
1812                     term->tabs[term->curs.x] = TRUE;
1813                     break;
1814
1815                   case ANSI('8', '#'):  /* ESC # 8 fills screen with Es :-) */
1816                     compatibility(VT100);
1817                     {
1818                         unsigned long *ldata;
1819                         int i, j;
1820                         pos scrtop, scrbot;
1821
1822                         for (i = 0; i < term->rows; i++) {
1823                             ldata = lineptr(i);
1824                             for (j = 0; j < term->cols; j++)
1825                                 ldata[j] = ATTR_DEFAULT | 'E';
1826                             ldata[term->cols] = 0;
1827                         }
1828                         term->disptop = 0;
1829                         term->seen_disp_event = TRUE;
1830                         scrtop.x = scrtop.y = 0;
1831                         scrbot.x = 0;
1832                         scrbot.y = term->rows;
1833                         check_selection(term, scrtop, scrbot);
1834                     }
1835                     break;
1836
1837                   case ANSI('3', '#'):
1838                   case ANSI('4', '#'):
1839                   case ANSI('5', '#'):
1840                   case ANSI('6', '#'):
1841                     compatibility(VT100);
1842                     {
1843                         unsigned long nlattr;
1844                         unsigned long *ldata;
1845                         switch (ANSI(c, term->esc_query)) {
1846                           case ANSI('3', '#'):
1847                             nlattr = LATTR_TOP;
1848                             break;
1849                           case ANSI('4', '#'):
1850                             nlattr = LATTR_BOT;
1851                             break;
1852                           case ANSI('5', '#'):
1853                             nlattr = LATTR_NORM;
1854                             break;
1855                           default: /* spiritually case ANSI('6', '#'): */
1856                             nlattr = LATTR_WIDE;
1857                             break;
1858                         }
1859                         ldata = lineptr(term->curs.y);
1860                         ldata[term->cols] &= ~LATTR_MODE;
1861                         ldata[term->cols] |= nlattr;
1862                     }
1863                     break;
1864
1865                   case ANSI('A', '('):
1866                     compatibility(VT100);
1867                     if (!term->cfg.no_remote_charset)
1868                         term->cset_attr[0] = ATTR_GBCHR;
1869                     break;
1870                   case ANSI('B', '('):
1871                     compatibility(VT100);
1872                     if (!term->cfg.no_remote_charset)
1873                         term->cset_attr[0] = ATTR_ASCII;
1874                     break;
1875                   case ANSI('0', '('):
1876                     compatibility(VT100);
1877                     if (!term->cfg.no_remote_charset)
1878                         term->cset_attr[0] = ATTR_LINEDRW;
1879                     break;
1880                   case ANSI('U', '('):
1881                     compatibility(OTHER);
1882                     if (!term->cfg.no_remote_charset)
1883                         term->cset_attr[0] = ATTR_SCOACS;
1884                     break;
1885
1886                   case ANSI('A', ')'):
1887                     compatibility(VT100);
1888                     if (!term->cfg.no_remote_charset)
1889                         term->cset_attr[1] = ATTR_GBCHR;
1890                     break;
1891                   case ANSI('B', ')'):
1892                     compatibility(VT100);
1893                     if (!term->cfg.no_remote_charset)
1894                         term->cset_attr[1] = ATTR_ASCII;
1895                     break;
1896                   case ANSI('0', ')'):
1897                     compatibility(VT100);
1898                     if (!term->cfg.no_remote_charset)
1899                         term->cset_attr[1] = ATTR_LINEDRW;
1900                     break;
1901                   case ANSI('U', ')'):
1902                     compatibility(OTHER);
1903                     if (!term->cfg.no_remote_charset)
1904                         term->cset_attr[1] = ATTR_SCOACS;
1905                     break;
1906
1907                   case ANSI('8', '%'):  /* Old Linux code */
1908                   case ANSI('G', '%'):
1909                     compatibility(OTHER);
1910                     if (!term->cfg.no_remote_charset)
1911                         term->utf = 1;
1912                     break;
1913                   case ANSI('@', '%'):
1914                     compatibility(OTHER);
1915                     if (!term->cfg.no_remote_charset)
1916                         term->utf = 0;
1917                     break;
1918                 }
1919                 break;
1920               case SEEN_CSI:
1921                 term->termstate = TOPLEVEL;  /* default */
1922                 if (isdigit(c)) {
1923                     if (term->esc_nargs <= ARGS_MAX) {
1924                         if (term->esc_args[term->esc_nargs - 1] == ARG_DEFAULT)
1925                             term->esc_args[term->esc_nargs - 1] = 0;
1926                         term->esc_args[term->esc_nargs - 1] =
1927                             10 * term->esc_args[term->esc_nargs - 1] + c - '0';
1928                     }
1929                     term->termstate = SEEN_CSI;
1930                 } else if (c == ';') {
1931                     if (++term->esc_nargs <= ARGS_MAX)
1932                         term->esc_args[term->esc_nargs - 1] = ARG_DEFAULT;
1933                     term->termstate = SEEN_CSI;
1934                 } else if (c < '@') {
1935                     if (term->esc_query)
1936                         term->esc_query = -1;
1937                     else if (c == '?')
1938                         term->esc_query = TRUE;
1939                     else
1940                         term->esc_query = c;
1941                     term->termstate = SEEN_CSI;
1942                 } else
1943                     switch (ANSI(c, term->esc_query)) {
1944                       case 'A':       /* move up N lines */
1945                         move(term, term->curs.x,
1946                              term->curs.y - def(term->esc_args[0], 1), 1);
1947                         term->seen_disp_event = TRUE;
1948                         break;
1949                       case 'e':       /* move down N lines */
1950                         compatibility(ANSI);
1951                         /* FALLTHROUGH */
1952                       case 'B':
1953                         move(term, term->curs.x,
1954                              term->curs.y + def(term->esc_args[0], 1), 1);
1955                         term->seen_disp_event = TRUE;
1956                         break;
1957                       case ANSI('c', '>'):      /* report xterm version */
1958                         compatibility(OTHER);
1959                         /* this reports xterm version 136 so that VIM can
1960                            use the drag messages from the mouse reporting */
1961                         if (term->ldisc)
1962                             ldisc_send(term->ldisc, "\033[>0;136;0c", 11, 0);
1963                         break;
1964                       case 'a':       /* move right N cols */
1965                         compatibility(ANSI);
1966                         /* FALLTHROUGH */
1967                       case 'C':
1968                         move(term, term->curs.x + def(term->esc_args[0], 1),
1969                              term->curs.y, 1);
1970                         term->seen_disp_event = TRUE;
1971                         break;
1972                       case 'D':       /* move left N cols */
1973                         move(term, term->curs.x - def(term->esc_args[0], 1),
1974                              term->curs.y, 1);
1975                         term->seen_disp_event = TRUE;
1976                         break;
1977                       case 'E':       /* move down N lines and CR */
1978                         compatibility(ANSI);
1979                         move(term, 0,
1980                              term->curs.y + def(term->esc_args[0], 1), 1);
1981                         term->seen_disp_event = TRUE;
1982                         break;
1983                       case 'F':       /* move up N lines and CR */
1984                         compatibility(ANSI);
1985                         move(term, 0,
1986                              term->curs.y - def(term->esc_args[0], 1), 1);
1987                         term->seen_disp_event = TRUE;
1988                         break;
1989                       case 'G':
1990                       case '`':       /* set horizontal posn */
1991                         compatibility(ANSI);
1992                         move(term, def(term->esc_args[0], 1) - 1,
1993                              term->curs.y, 0);
1994                         term->seen_disp_event = TRUE;
1995                         break;
1996                       case 'd':       /* set vertical posn */
1997                         compatibility(ANSI);
1998                         move(term, term->curs.x,
1999                              ((term->dec_om ? term->marg_t : 0) +
2000                               def(term->esc_args[0], 1) - 1),
2001                              (term->dec_om ? 2 : 0));
2002                         term->seen_disp_event = TRUE;
2003                         break;
2004                       case 'H':
2005                       case 'f':       /* set horz and vert posns at once */
2006                         if (term->esc_nargs < 2)
2007                             term->esc_args[1] = ARG_DEFAULT;
2008                         move(term, def(term->esc_args[1], 1) - 1,
2009                              ((term->dec_om ? term->marg_t : 0) +
2010                               def(term->esc_args[0], 1) - 1),
2011                              (term->dec_om ? 2 : 0));
2012                         term->seen_disp_event = TRUE;
2013                         break;
2014                       case 'J':       /* erase screen or parts of it */
2015                         {
2016                             unsigned int i = def(term->esc_args[0], 0) + 1;
2017                             if (i > 3)
2018                                 i = 0;
2019                             erase_lots(term, FALSE, !!(i & 2), !!(i & 1));
2020                         }
2021                         term->disptop = 0;
2022                         term->seen_disp_event = TRUE;
2023                         break;
2024                       case 'K':       /* erase line or parts of it */
2025                         {
2026                             unsigned int i = def(term->esc_args[0], 0) + 1;
2027                             if (i > 3)
2028                                 i = 0;
2029                             erase_lots(term, TRUE, !!(i & 2), !!(i & 1));
2030                         }
2031                         term->seen_disp_event = TRUE;
2032                         break;
2033                       case 'L':       /* insert lines */
2034                         compatibility(VT102);
2035                         if (term->curs.y <= term->marg_b)
2036                             scroll(term, term->curs.y, term->marg_b,
2037                                    -def(term->esc_args[0], 1), FALSE);
2038                         fix_cpos;
2039                         term->seen_disp_event = TRUE;
2040                         break;
2041                       case 'M':       /* delete lines */
2042                         compatibility(VT102);
2043                         if (term->curs.y <= term->marg_b)
2044                             scroll(term, term->curs.y, term->marg_b,
2045                                    def(term->esc_args[0], 1),
2046                                    TRUE);
2047                         fix_cpos;
2048                         term->seen_disp_event = TRUE;
2049                         break;
2050                       case '@':       /* insert chars */
2051                         /* XXX VTTEST says this is vt220, vt510 manual says vt102 */
2052                         compatibility(VT102);
2053                         insch(term, def(term->esc_args[0], 1));
2054                         term->seen_disp_event = TRUE;
2055                         break;
2056                       case 'P':       /* delete chars */
2057                         compatibility(VT102);
2058                         insch(term, -def(term->esc_args[0], 1));
2059                         term->seen_disp_event = TRUE;
2060                         break;
2061                       case 'c':       /* terminal type query */
2062                         compatibility(VT100);
2063                         /* This is the response for a VT102 */
2064                         if (term->ldisc)
2065                             ldisc_send(term->ldisc, term->id_string,
2066                                        strlen(term->id_string), 0);
2067                         break;
2068                       case 'n':       /* cursor position query */
2069                         if (term->ldisc) {
2070                             if (term->esc_args[0] == 6) {
2071                                 char buf[32];
2072                                 sprintf(buf, "\033[%d;%dR", term->curs.y + 1,
2073                                         term->curs.x + 1);
2074                                 ldisc_send(term->ldisc, buf, strlen(buf), 0);
2075                             } else if (term->esc_args[0] == 5) {
2076                                 ldisc_send(term->ldisc, "\033[0n", 4, 0);
2077                             }
2078                         }
2079                         break;
2080                       case 'h':       /* toggle modes to high */
2081                       case ANSI_QUE('h'):
2082                         compatibility(VT100);
2083                         {
2084                             int i;
2085                             for (i = 0; i < term->esc_nargs; i++)
2086                                 toggle_mode(term, term->esc_args[i],
2087                                             term->esc_query, TRUE);
2088                         }
2089                         break;
2090                       case 'i':
2091                       case ANSI_QUE('i'):
2092                         compatibility(VT100);
2093                         {
2094                             if (term->esc_nargs != 1) break;
2095                             if (term->esc_args[0] == 5 && *term->cfg.printer) {
2096                                 term->printing = TRUE;
2097                                 term->only_printing = !term->esc_query;
2098                                 term->print_state = 0;
2099                                 term_print_setup(term);
2100                             } else if (term->esc_args[0] == 4 &&
2101                                        term->printing) {
2102                                 term_print_finish(term);
2103                             }
2104                         }
2105                         break;
2106                       case 'l':       /* toggle modes to low */
2107                       case ANSI_QUE('l'):
2108                         compatibility(VT100);
2109                         {
2110                             int i;
2111                             for (i = 0; i < term->esc_nargs; i++)
2112                                 toggle_mode(term, term->esc_args[i],
2113                                             term->esc_query, FALSE);
2114                         }
2115                         break;
2116                       case 'g':       /* clear tabs */
2117                         compatibility(VT100);
2118                         if (term->esc_nargs == 1) {
2119                             if (term->esc_args[0] == 0) {
2120                                 term->tabs[term->curs.x] = FALSE;
2121                             } else if (term->esc_args[0] == 3) {
2122                                 int i;
2123                                 for (i = 0; i < term->cols; i++)
2124                                     term->tabs[i] = FALSE;
2125                             }
2126                         }
2127                         break;
2128                       case 'r':       /* set scroll margins */
2129                         compatibility(VT100);
2130                         if (term->esc_nargs <= 2) {
2131                             int top, bot;
2132                             top = def(term->esc_args[0], 1) - 1;
2133                             bot = (term->esc_nargs <= 1
2134                                    || term->esc_args[1] == 0 ?
2135                                    term->rows :
2136                                    def(term->esc_args[1], term->rows)) - 1;
2137                             if (bot >= term->rows)
2138                                 bot = term->rows - 1;
2139                             /* VTTEST Bug 9 - if region is less than 2 lines
2140                              * don't change region.
2141                              */
2142                             if (bot - top > 0) {
2143                                 term->marg_t = top;
2144                                 term->marg_b = bot;
2145                                 term->curs.x = 0;
2146                                 /*
2147                                  * I used to think the cursor should be
2148                                  * placed at the top of the newly marginned
2149                                  * area. Apparently not: VMS TPU falls over
2150                                  * if so.
2151                                  *
2152                                  * Well actually it should for
2153                                  * Origin mode - RDB
2154                                  */
2155                                 term->curs.y = (term->dec_om ?
2156                                                 term->marg_t : 0);
2157                                 fix_cpos;
2158                                 term->seen_disp_event = TRUE;
2159                             }
2160                         }
2161                         break;
2162                       case 'm':       /* set graphics rendition */
2163                         {
2164                             /*
2165                              * A VT100 without the AVO only had one
2166                              * attribute, either underline or
2167                              * reverse video depending on the
2168                              * cursor type, this was selected by
2169                              * CSI 7m.
2170                              *
2171                              * case 2:
2172                              *  This is sometimes DIM, eg on the
2173                              *  GIGI and Linux
2174                              * case 8:
2175                              *  This is sometimes INVIS various ANSI.
2176                              * case 21:
2177                              *  This like 22 disables BOLD, DIM and INVIS
2178                              *
2179                              * The ANSI colours appear on any
2180                              * terminal that has colour (obviously)
2181                              * but the interaction between sgr0 and
2182                              * the colours varies but is usually
2183                              * related to the background colour
2184                              * erase item. The interaction between
2185                              * colour attributes and the mono ones
2186                              * is also very implementation
2187                              * dependent.
2188                              *
2189                              * The 39 and 49 attributes are likely
2190                              * to be unimplemented.
2191                              */
2192                             int i;
2193                             for (i = 0; i < term->esc_nargs; i++) {
2194                                 switch (def(term->esc_args[i], 0)) {
2195                                   case 0:       /* restore defaults */
2196                                     term->curr_attr = ATTR_DEFAULT;
2197                                     break;
2198                                   case 1:       /* enable bold */
2199                                     compatibility(VT100AVO);
2200                                     term->curr_attr |= ATTR_BOLD;
2201                                     break;
2202                                   case 21:      /* (enable double underline) */
2203                                     compatibility(OTHER);
2204                                   case 4:       /* enable underline */
2205                                     compatibility(VT100AVO);
2206                                     term->curr_attr |= ATTR_UNDER;
2207                                     break;
2208                                   case 5:       /* enable blink */
2209                                     compatibility(VT100AVO);
2210                                     term->curr_attr |= ATTR_BLINK;
2211                                     break;
2212                                   case 7:       /* enable reverse video */
2213                                     term->curr_attr |= ATTR_REVERSE;
2214                                     break;
2215                                   case 10:      /* SCO acs off */
2216                                     compatibility(SCOANSI);
2217                                     if (term->cfg.no_remote_charset) break;
2218                                     term->sco_acs = 0; break;
2219                                   case 11:      /* SCO acs on */
2220                                     compatibility(SCOANSI);
2221                                     if (term->cfg.no_remote_charset) break;
2222                                     term->sco_acs = 1; break;
2223                                   case 12:      /* SCO acs on, |0x80 */
2224                                     compatibility(SCOANSI);
2225                                     if (term->cfg.no_remote_charset) break;
2226                                     term->sco_acs = 2; break;
2227                                   case 22:      /* disable bold */
2228                                     compatibility2(OTHER, VT220);
2229                                     term->curr_attr &= ~ATTR_BOLD;
2230                                     break;
2231                                   case 24:      /* disable underline */
2232                                     compatibility2(OTHER, VT220);
2233                                     term->curr_attr &= ~ATTR_UNDER;
2234                                     break;
2235                                   case 25:      /* disable blink */
2236                                     compatibility2(OTHER, VT220);
2237                                     term->curr_attr &= ~ATTR_BLINK;
2238                                     break;
2239                                   case 27:      /* disable reverse video */
2240                                     compatibility2(OTHER, VT220);
2241                                     term->curr_attr &= ~ATTR_REVERSE;
2242                                     break;
2243                                   case 30:
2244                                   case 31:
2245                                   case 32:
2246                                   case 33:
2247                                   case 34:
2248                                   case 35:
2249                                   case 36:
2250                                   case 37:
2251                                     /* foreground */
2252                                     term->curr_attr &= ~ATTR_FGMASK;
2253                                     term->curr_attr |=
2254                                         (term->esc_args[i] - 30)<<ATTR_FGSHIFT;
2255                                     break;
2256                                   case 39:      /* default-foreground */
2257                                     term->curr_attr &= ~ATTR_FGMASK;
2258                                     term->curr_attr |= ATTR_DEFFG;
2259                                     break;
2260                                   case 40:
2261                                   case 41:
2262                                   case 42:
2263                                   case 43:
2264                                   case 44:
2265                                   case 45:
2266                                   case 46:
2267                                   case 47:
2268                                     /* background */
2269                                     term->curr_attr &= ~ATTR_BGMASK;
2270                                     term->curr_attr |=
2271                                         (term->esc_args[i] - 40)<<ATTR_BGSHIFT;
2272                                     break;
2273                                   case 49:      /* default-background */
2274                                     term->curr_attr &= ~ATTR_BGMASK;
2275                                     term->curr_attr |= ATTR_DEFBG;
2276                                     break;
2277                                 }
2278                             }
2279                             if (term->use_bce)
2280                                 term->erase_char = (' ' | ATTR_ASCII |
2281                                                     (term->curr_attr &
2282                                                      (ATTR_FGMASK |
2283                                                       ATTR_BGMASK)));
2284                         }
2285                         break;
2286                       case 's':       /* save cursor */
2287                         save_cursor(term, TRUE);
2288                         break;
2289                       case 'u':       /* restore cursor */
2290                         save_cursor(term, FALSE);
2291                         term->seen_disp_event = TRUE;
2292                         break;
2293                       case 't':       /* set page size - ie window height */
2294                         /*
2295                          * VT340/VT420 sequence DECSLPP, DEC only allows values
2296                          *  24/25/36/48/72/144 other emulators (eg dtterm) use
2297                          * illegal values (eg first arg 1..9) for window changing
2298                          * and reports.
2299                          */
2300                         if (term->esc_nargs <= 1
2301                             && (term->esc_args[0] < 1 ||
2302                                 term->esc_args[0] >= 24)) {
2303                             compatibility(VT340TEXT);
2304                             if (!term->cfg.no_remote_resize)
2305                                 request_resize(term->frontend, term->cols,
2306                                                def(term->esc_args[0], 24));
2307                             deselect(term);
2308                         } else if (term->esc_nargs >= 1 &&
2309                                    term->esc_args[0] >= 1 &&
2310                                    term->esc_args[0] < 24) {
2311                             compatibility(OTHER);
2312
2313                             switch (term->esc_args[0]) {
2314                                 int x, y, len;
2315                                 char buf[80], *p;
2316                               case 1:
2317                                 set_iconic(term->frontend, FALSE);
2318                                 break;
2319                               case 2:
2320                                 set_iconic(term->frontend, TRUE);
2321                                 break;
2322                               case 3:
2323                                 if (term->esc_nargs >= 3) {
2324                                     if (!term->cfg.no_remote_resize)
2325                                         move_window(term->frontend,
2326                                                     def(term->esc_args[1], 0),
2327                                                     def(term->esc_args[2], 0));
2328                                 }
2329                                 break;
2330                               case 4:
2331                                 /* We should resize the window to a given
2332                                  * size in pixels here, but currently our
2333                                  * resizing code isn't healthy enough to
2334                                  * manage it. */
2335                                 break;
2336                               case 5:
2337                                 /* move to top */
2338                                 set_zorder(term->frontend, TRUE);
2339                                 break;
2340                               case 6:
2341                                 /* move to bottom */
2342                                 set_zorder(term->frontend, FALSE);
2343                                 break;
2344                               case 7:
2345                                 refresh_window(term->frontend);
2346                                 break;
2347                               case 8:
2348                                 if (term->esc_nargs >= 3) {
2349                                     if (!term->cfg.no_remote_resize)
2350                                         request_resize(term->frontend,
2351                                                        def(term->esc_args[2], term->cfg.width),
2352                                                        def(term->esc_args[1], term->cfg.height));
2353                                 }
2354                                 break;
2355                               case 9:
2356                                 if (term->esc_nargs >= 2)
2357                                     set_zoomed(term->frontend,
2358                                                term->esc_args[1] ?
2359                                                TRUE : FALSE);
2360                                 break;
2361                               case 11:
2362                                 if (term->ldisc)
2363                                     ldisc_send(term->ldisc,
2364                                                is_iconic(term->frontend) ?
2365                                                "\033[1t" : "\033[2t", 4, 0);
2366                                 break;
2367                               case 13:
2368                                 if (term->ldisc) {
2369                                     get_window_pos(term->frontend, &x, &y);
2370                                     len = sprintf(buf, "\033[3;%d;%dt", x, y);
2371                                     ldisc_send(term->ldisc, buf, len, 0);
2372                                 }
2373                                 break;
2374                               case 14:
2375                                 if (term->ldisc) {
2376                                     get_window_pixels(term->frontend, &x, &y);
2377                                     len = sprintf(buf, "\033[4;%d;%dt", x, y);
2378                                     ldisc_send(term->ldisc, buf, len, 0);
2379                                 }
2380                                 break;
2381                               case 18:
2382                                 if (term->ldisc) {
2383                                     len = sprintf(buf, "\033[8;%d;%dt",
2384                                                   term->rows, term->cols);
2385                                     ldisc_send(term->ldisc, buf, len, 0);
2386                                 }
2387                                 break;
2388                               case 19:
2389                                 /*
2390                                  * Hmmm. Strictly speaking we
2391                                  * should return `the size of the
2392                                  * screen in characters', but
2393                                  * that's not easy: (a) window
2394                                  * furniture being what it is it's
2395                                  * hard to compute, and (b) in
2396                                  * resize-font mode maximising the
2397                                  * window wouldn't change the
2398                                  * number of characters. *shrug*. I
2399                                  * think we'll ignore it for the
2400                                  * moment and see if anyone
2401                                  * complains, and then ask them
2402                                  * what they would like it to do.
2403                                  */
2404                                 break;
2405                               case 20:
2406                                 if (term->ldisc) {
2407                                     p = get_window_title(term->frontend, TRUE);
2408                                     len = strlen(p);
2409                                     ldisc_send(term->ldisc, "\033]L", 3, 0);
2410                                     ldisc_send(term->ldisc, p, len, 0);
2411                                     ldisc_send(term->ldisc, "\033\\", 2, 0);
2412                                 }
2413                                 break;
2414                               case 21:
2415                                 if (term->ldisc) {
2416                                     p = get_window_title(term->frontend,FALSE);
2417                                     len = strlen(p);
2418                                     ldisc_send(term->ldisc, "\033]l", 3, 0);
2419                                     ldisc_send(term->ldisc, p, len, 0);
2420                                     ldisc_send(term->ldisc, "\033\\", 2, 0);
2421                                 }
2422                                 break;
2423                             }
2424                         }
2425                         break;
2426                       case 'S':
2427                         compatibility(SCOANSI);
2428                         scroll(term, term->marg_t, term->marg_b,
2429                                def(term->esc_args[0], 1), TRUE);
2430                         fix_cpos;
2431                         term->wrapnext = FALSE;
2432                         term->seen_disp_event = TRUE;
2433                         break;
2434                       case 'T':
2435                         compatibility(SCOANSI);
2436                         scroll(term, term->marg_t, term->marg_b,
2437                                -def(term->esc_args[0], 1), TRUE);
2438                         fix_cpos;
2439                         term->wrapnext = FALSE;
2440                         term->seen_disp_event = TRUE;
2441                         break;
2442                       case ANSI('|', '*'):
2443                         /* VT420 sequence DECSNLS
2444                          * Set number of lines on screen
2445                          * VT420 uses VGA like hardware and can support any size in
2446                          * reasonable range (24..49 AIUI) with no default specified.
2447                          */
2448                         compatibility(VT420);
2449                         if (term->esc_nargs == 1 && term->esc_args[0] > 0) {
2450                             if (!term->cfg.no_remote_resize)
2451                                 request_resize(term->frontend, term->cols,
2452                                                def(term->esc_args[0],
2453                                                    term->cfg.height));
2454                             deselect(term);
2455                         }
2456                         break;
2457                       case ANSI('|', '$'):
2458                         /* VT340/VT420 sequence DECSCPP
2459                          * Set number of columns per page
2460                          * Docs imply range is only 80 or 132, but I'll allow any.
2461                          */
2462                         compatibility(VT340TEXT);
2463                         if (term->esc_nargs <= 1) {
2464                             if (!term->cfg.no_remote_resize)
2465                                 request_resize(term->frontend,
2466                                                def(term->esc_args[0],
2467                                                    term->cfg.width), term->rows);
2468                             deselect(term);
2469                         }
2470                         break;
2471                       case 'X':       /* write N spaces w/o moving cursor */
2472                         /* XXX VTTEST says this is vt220, vt510 manual says vt100 */
2473                         compatibility(ANSIMIN);
2474                         {
2475                             int n = def(term->esc_args[0], 1);
2476                             pos cursplus;
2477                             unsigned long *p = term->cpos;
2478                             if (n > term->cols - term->curs.x)
2479                                 n = term->cols - term->curs.x;
2480                             cursplus = term->curs;
2481                             cursplus.x += n;
2482                             check_boundary(term, term->curs.x, term->curs.y);
2483                             check_boundary(term, term->curs.x+n, term->curs.y);
2484                             check_selection(term, term->curs, cursplus);
2485                             while (n--)
2486                                 *p++ = term->erase_char;
2487                             term->seen_disp_event = TRUE;
2488                         }
2489                         break;
2490                       case 'x':       /* report terminal characteristics */
2491                         compatibility(VT100);
2492                         if (term->ldisc) {
2493                             char buf[32];
2494                             int i = def(term->esc_args[0], 0);
2495                             if (i == 0 || i == 1) {
2496                                 strcpy(buf, "\033[2;1;1;112;112;1;0x");
2497                                 buf[2] += i;
2498                                 ldisc_send(term->ldisc, buf, 20, 0);
2499                             }
2500                         }
2501                         break;
2502                       case 'Z':         /* BackTab for xterm */
2503                         compatibility(OTHER);
2504                         {
2505                             int i = def(term->esc_args[0], 1);
2506                             pos old_curs = term->curs;
2507
2508                             for(;i>0 && term->curs.x>0; i--) {
2509                                 do {
2510                                     term->curs.x--;
2511                                 } while (term->curs.x >0 &&
2512                                          !term->tabs[term->curs.x]);
2513                             }
2514                             fix_cpos;
2515                             check_selection(term, old_curs, term->curs);
2516                         }
2517                         break;
2518                       case ANSI('L', '='):
2519                         compatibility(OTHER);
2520                         term->use_bce = (term->esc_args[0] <= 0);
2521                         term->erase_char = ERASE_CHAR;
2522                         if (term->use_bce)
2523                             term->erase_char = (' ' | ATTR_ASCII |
2524                                                 (term->curr_attr &
2525                                                  (ATTR_FGMASK | ATTR_BGMASK)));
2526                         break;
2527                       case ANSI('E', '='):
2528                         compatibility(OTHER);
2529                         term->blink_is_real = (term->esc_args[0] >= 1);
2530                         break;
2531                       case ANSI('p', '"'):
2532                         /*
2533                          * Allow the host to make this emulator a
2534                          * 'perfect' VT102. This first appeared in
2535                          * the VT220, but we do need to get back to
2536                          * PuTTY mode so I won't check it.
2537                          *
2538                          * The arg in 40..42,50 are a PuTTY extension.
2539                          * The 2nd arg, 8bit vs 7bit is not checked.
2540                          *
2541                          * Setting VT102 mode should also change
2542                          * the Fkeys to generate PF* codes as a
2543                          * real VT102 has no Fkeys. The VT220 does
2544                          * this, F11..F13 become ESC,BS,LF other
2545                          * Fkeys send nothing.
2546                          *
2547                          * Note ESC c will NOT change this!
2548                          */
2549
2550                         switch (term->esc_args[0]) {
2551                           case 61:
2552                             term->compatibility_level &= ~TM_VTXXX;
2553                             term->compatibility_level |= TM_VT102;
2554                             break;
2555                           case 62:
2556                             term->compatibility_level &= ~TM_VTXXX;
2557                             term->compatibility_level |= TM_VT220;
2558                             break;
2559
2560                           default:
2561                             if (term->esc_args[0] > 60 &&
2562                                 term->esc_args[0] < 70)
2563                                 term->compatibility_level |= TM_VTXXX;
2564                             break;
2565
2566                           case 40:
2567                             term->compatibility_level &= TM_VTXXX;
2568                             break;
2569                           case 41:
2570                             term->compatibility_level = TM_PUTTY;
2571                             break;
2572                           case 42:
2573                             term->compatibility_level = TM_SCOANSI;
2574                             break;
2575
2576                           case ARG_DEFAULT:
2577                             term->compatibility_level = TM_PUTTY;
2578                             break;
2579                           case 50:
2580                             break;
2581                         }
2582
2583                         /* Change the response to CSI c */
2584                         if (term->esc_args[0] == 50) {
2585                             int i;
2586                             char lbuf[64];
2587                             strcpy(term->id_string, "\033[?");
2588                             for (i = 1; i < term->esc_nargs; i++) {
2589                                 if (i != 1)
2590                                     strcat(term->id_string, ";");
2591                                 sprintf(lbuf, "%d", term->esc_args[i]);
2592                                 strcat(term->id_string, lbuf);
2593                             }
2594                             strcat(term->id_string, "c");
2595                         }
2596 #if 0
2597                         /* Is this a good idea ?
2598                          * Well we should do a soft reset at this point ...
2599                          */
2600                         if (!has_compat(VT420) && has_compat(VT100)) {
2601                             if (!term->cfg.no_remote_resize) {
2602                                 if (term->reset_132)
2603                                     request_resize(132, 24);
2604                                 else
2605                                     request_resize(80, 24);
2606                             }
2607                         }
2608 #endif
2609                         break;
2610                     }
2611                 break;
2612               case SEEN_OSC:
2613                 term->osc_w = FALSE;
2614                 switch (c) {
2615                   case 'P':            /* Linux palette sequence */
2616                     term->termstate = SEEN_OSC_P;
2617                     term->osc_strlen = 0;
2618                     break;
2619                   case 'R':            /* Linux palette reset */
2620                     palette_reset(term->frontend);
2621                     term_invalidate(term);
2622                     term->termstate = TOPLEVEL;
2623                     break;
2624                   case 'W':            /* word-set */
2625                     term->termstate = SEEN_OSC_W;
2626                     term->osc_w = TRUE;
2627                     break;
2628                   case '0':
2629                   case '1':
2630                   case '2':
2631                   case '3':
2632                   case '4':
2633                   case '5':
2634                   case '6':
2635                   case '7':
2636                   case '8':
2637                   case '9':
2638                     term->esc_args[0] = 10 * term->esc_args[0] + c - '0';
2639                     break;
2640                   case 'L':
2641                     /*
2642                      * Grotty hack to support xterm and DECterm title
2643                      * sequences concurrently.
2644                      */
2645                     if (term->esc_args[0] == 2) {
2646                         term->esc_args[0] = 1;
2647                         break;
2648                     }
2649                     /* else fall through */
2650                   default:
2651                     term->termstate = OSC_STRING;
2652                     term->osc_strlen = 0;
2653                 }
2654                 break;
2655               case OSC_STRING:
2656                 /*
2657                  * This OSC stuff is EVIL. It takes just one character to get into
2658                  * sysline mode and it's not initially obvious how to get out.
2659                  * So I've added CR and LF as string aborts.
2660                  * This shouldn't effect compatibility as I believe embedded
2661                  * control characters are supposed to be interpreted (maybe?)
2662                  * and they don't display anything useful anyway.
2663                  *
2664                  * -- RDB
2665                  */
2666                 if (c == '\012' || c == '\015') {
2667                     term->termstate = TOPLEVEL;
2668                 } else if (c == 0234 || c == '\007') {
2669                     /*
2670                      * These characters terminate the string; ST and BEL
2671                      * terminate the sequence and trigger instant
2672                      * processing of it, whereas ESC goes back to SEEN_ESC
2673                      * mode unless it is followed by \, in which case it is
2674                      * synonymous with ST in the first place.
2675                      */
2676                     do_osc(term);
2677                     term->termstate = TOPLEVEL;
2678                 } else if (c == '\033')
2679                     term->termstate = OSC_MAYBE_ST;
2680                 else if (term->osc_strlen < OSC_STR_MAX)
2681                     term->osc_string[term->osc_strlen++] = c;
2682                 break;
2683               case SEEN_OSC_P:
2684                 {
2685                     int max = (term->osc_strlen == 0 ? 21 : 16);
2686                     int val;
2687                     if (c >= '0' && c <= '9')
2688                         val = c - '0';
2689                     else if (c >= 'A' && c <= 'A' + max - 10)
2690                         val = c - 'A' + 10;
2691                     else if (c >= 'a' && c <= 'a' + max - 10)
2692                         val = c - 'a' + 10;
2693                     else {
2694                         term->termstate = TOPLEVEL;
2695                         break;
2696                     }
2697                     term->osc_string[term->osc_strlen++] = val;
2698                     if (term->osc_strlen >= 7) {
2699                         palette_set(term->frontend, term->osc_string[0],
2700                                     term->osc_string[1] * 16 + term->osc_string[2],
2701                                     term->osc_string[3] * 16 + term->osc_string[4],
2702                                     term->osc_string[5] * 16 + term->osc_string[6]);
2703                         term_invalidate(term);
2704                         term->termstate = TOPLEVEL;
2705                     }
2706                 }
2707                 break;
2708               case SEEN_OSC_W:
2709                 switch (c) {
2710                   case '0':
2711                   case '1':
2712                   case '2':
2713                   case '3':
2714                   case '4':
2715                   case '5':
2716                   case '6':
2717                   case '7':
2718                   case '8':
2719                   case '9':
2720                     term->esc_args[0] = 10 * term->esc_args[0] + c - '0';
2721                     break;
2722                   default:
2723                     term->termstate = OSC_STRING;
2724                     term->osc_strlen = 0;
2725                 }
2726                 break;
2727               case VT52_ESC:
2728                 term->termstate = TOPLEVEL;
2729                 term->seen_disp_event = TRUE;
2730                 switch (c) {
2731                   case 'A':
2732                     move(term, term->curs.x, term->curs.y - 1, 1);
2733                     break;
2734                   case 'B':
2735                     move(term, term->curs.x, term->curs.y + 1, 1);
2736                     break;
2737                   case 'C':
2738                     move(term, term->curs.x + 1, term->curs.y, 1);
2739                     break;
2740                   case 'D':
2741                     move(term, term->curs.x - 1, term->curs.y, 1);
2742                     break;
2743                     /*
2744                      * From the VT100 Manual
2745                      * NOTE: The special graphics characters in the VT100
2746                      *       are different from those in the VT52
2747                      *
2748                      * From VT102 manual:
2749                      *       137 _  Blank             - Same
2750                      *       140 `  Reserved          - Humm.
2751                      *       141 a  Solid rectangle   - Similar
2752                      *       142 b  1/                - Top half of fraction for the
2753                      *       143 c  3/                - subscript numbers below.
2754                      *       144 d  5/
2755                      *       145 e  7/
2756                      *       146 f  Degrees           - Same
2757                      *       147 g  Plus or minus     - Same
2758                      *       150 h  Right arrow
2759                      *       151 i  Ellipsis (dots)
2760                      *       152 j  Divide by
2761                      *       153 k  Down arrow
2762                      *       154 l  Bar at scan 0
2763                      *       155 m  Bar at scan 1
2764                      *       156 n  Bar at scan 2
2765                      *       157 o  Bar at scan 3     - Similar
2766                      *       160 p  Bar at scan 4     - Similar
2767                      *       161 q  Bar at scan 5     - Similar
2768                      *       162 r  Bar at scan 6     - Same
2769                      *       163 s  Bar at scan 7     - Similar
2770                      *       164 t  Subscript 0
2771                      *       165 u  Subscript 1
2772                      *       166 v  Subscript 2
2773                      *       167 w  Subscript 3
2774                      *       170 x  Subscript 4
2775                      *       171 y  Subscript 5
2776                      *       172 z  Subscript 6
2777                      *       173 {  Subscript 7
2778                      *       174 |  Subscript 8
2779                      *       175 }  Subscript 9
2780                      *       176 ~  Paragraph
2781                      *
2782                      */
2783                   case 'F':
2784                     term->cset_attr[term->cset = 0] = ATTR_LINEDRW;
2785                     break;
2786                   case 'G':
2787                     term->cset_attr[term->cset = 0] = ATTR_ASCII;
2788                     break;
2789                   case 'H':
2790                     move(term, 0, 0, 0);
2791                     break;
2792                   case 'I':
2793                     if (term->curs.y == 0)
2794                         scroll(term, 0, term->rows - 1, -1, TRUE);
2795                     else if (term->curs.y > 0)
2796                         term->curs.y--;
2797                     fix_cpos;
2798                     term->wrapnext = FALSE;
2799                     break;
2800                   case 'J':
2801                     erase_lots(term, FALSE, FALSE, TRUE);
2802                     term->disptop = 0;
2803                     break;
2804                   case 'K':
2805                     erase_lots(term, TRUE, FALSE, TRUE);
2806                     break;
2807 #if 0
2808                   case 'V':
2809                     /* XXX Print cursor line */
2810                     break;
2811                   case 'W':
2812                     /* XXX Start controller mode */
2813                     break;
2814                   case 'X':
2815                     /* XXX Stop controller mode */
2816                     break;
2817 #endif
2818                   case 'Y':
2819                     term->termstate = VT52_Y1;
2820                     break;
2821                   case 'Z':
2822                     if (term->ldisc)
2823                         ldisc_send(term->ldisc, "\033/Z", 3, 0);
2824                     break;
2825                   case '=':
2826                     term->app_keypad_keys = TRUE;
2827                     break;
2828                   case '>':
2829                     term->app_keypad_keys = FALSE;
2830                     break;
2831                   case '<':
2832                     /* XXX This should switch to VT100 mode not current or default
2833                      *     VT mode. But this will only have effect in a VT220+
2834                      *     emulation.
2835                      */
2836                     term->vt52_mode = FALSE;
2837                     term->blink_is_real = term->cfg.blinktext;
2838                     break;
2839 #if 0
2840                   case '^':
2841                     /* XXX Enter auto print mode */
2842                     break;
2843                   case '_':
2844                     /* XXX Exit auto print mode */
2845                     break;
2846                   case ']':
2847                     /* XXX Print screen */
2848                     break;
2849 #endif
2850
2851 #ifdef VT52_PLUS
2852                   case 'E':
2853                     /* compatibility(ATARI) */
2854                     move(term, 0, 0, 0);
2855                     erase_lots(term, FALSE, FALSE, TRUE);
2856                     term->disptop = 0;
2857                     break;
2858                   case 'L':
2859                     /* compatibility(ATARI) */
2860                     if (term->curs.y <= term->marg_b)
2861                         scroll(term, term->curs.y, term->marg_b, -1, FALSE);
2862                     break;
2863                   case 'M':
2864                     /* compatibility(ATARI) */
2865                     if (term->curs.y <= term->marg_b)
2866                         scroll(term, term->curs.y, term->marg_b, 1, TRUE);
2867                     break;
2868                   case 'b':
2869                     /* compatibility(ATARI) */
2870                     term->termstate = VT52_FG;
2871                     break;
2872                   case 'c':
2873                     /* compatibility(ATARI) */
2874                     term->termstate = VT52_BG;
2875                     break;
2876                   case 'd':
2877                     /* compatibility(ATARI) */
2878                     erase_lots(term, FALSE, TRUE, FALSE);
2879                     term->disptop = 0;
2880                     break;
2881                   case 'e':
2882                     /* compatibility(ATARI) */
2883                     term->cursor_on = TRUE;
2884                     break;
2885                   case 'f':
2886                     /* compatibility(ATARI) */
2887                     term->cursor_on = FALSE;
2888                     break;
2889                     /* case 'j': Save cursor position - broken on ST */
2890                     /* case 'k': Restore cursor position */
2891                   case 'l':
2892                     /* compatibility(ATARI) */
2893                     erase_lots(term, TRUE, TRUE, TRUE);
2894                     term->curs.x = 0;
2895                     term->wrapnext = FALSE;
2896                     fix_cpos;
2897                     break;
2898                   case 'o':
2899                     /* compatibility(ATARI) */
2900                     erase_lots(term, TRUE, TRUE, FALSE);
2901                     break;
2902                   case 'p':
2903                     /* compatibility(ATARI) */
2904                     term->curr_attr |= ATTR_REVERSE;
2905                     break;
2906                   case 'q':
2907                     /* compatibility(ATARI) */
2908                     term->curr_attr &= ~ATTR_REVERSE;
2909                     break;
2910                   case 'v':            /* wrap Autowrap on - Wyse style */
2911                     /* compatibility(ATARI) */
2912                     term->wrap = 1;
2913                     break;
2914                   case 'w':            /* Autowrap off */
2915                     /* compatibility(ATARI) */
2916                     term->wrap = 0;
2917                     break;
2918
2919                   case 'R':
2920                     /* compatibility(OTHER) */
2921                     term->vt52_bold = FALSE;
2922                     term->curr_attr = ATTR_DEFAULT;
2923                     if (term->use_bce)
2924                         term->erase_char = (' ' | ATTR_ASCII |
2925                                             (term->curr_attr &
2926                                              (ATTR_FGMASK | ATTR_BGMASK)));
2927                     break;
2928                   case 'S':
2929                     /* compatibility(VI50) */
2930                     term->curr_attr |= ATTR_UNDER;
2931                     break;
2932                   case 'W':
2933                     /* compatibility(VI50) */
2934                     term->curr_attr &= ~ATTR_UNDER;
2935                     break;
2936                   case 'U':
2937                     /* compatibility(VI50) */
2938                     term->vt52_bold = TRUE;
2939                     term->curr_attr |= ATTR_BOLD;
2940                     break;
2941                   case 'T':
2942                     /* compatibility(VI50) */
2943                     term->vt52_bold = FALSE;
2944                     term->curr_attr &= ~ATTR_BOLD;
2945                     break;
2946 #endif
2947                 }
2948                 break;
2949               case VT52_Y1:
2950                 term->termstate = VT52_Y2;
2951                 move(term, term->curs.x, c - ' ', 0);
2952                 break;
2953               case VT52_Y2:
2954                 term->termstate = TOPLEVEL;
2955                 move(term, c - ' ', term->curs.y, 0);
2956                 break;
2957
2958 #ifdef VT52_PLUS
2959               case VT52_FG:
2960                 term->termstate = TOPLEVEL;
2961                 term->curr_attr &= ~ATTR_FGMASK;
2962                 term->curr_attr &= ~ATTR_BOLD;
2963                 term->curr_attr |= (c & 0x7) << ATTR_FGSHIFT;
2964                 if ((c & 0x8) || term->vt52_bold)
2965                     term->curr_attr |= ATTR_BOLD;
2966
2967                 if (term->use_bce)
2968                     term->erase_char = (' ' | ATTR_ASCII |
2969                                         (term->curr_attr &
2970                                          (ATTR_FGMASK | ATTR_BGMASK)));
2971                 break;
2972               case VT52_BG:
2973                 term->termstate = TOPLEVEL;
2974                 term->curr_attr &= ~ATTR_BGMASK;
2975                 term->curr_attr &= ~ATTR_BLINK;
2976                 term->curr_attr |= (c & 0x7) << ATTR_BGSHIFT;
2977
2978                 /* Note: bold background */
2979                 if (c & 0x8)
2980                     term->curr_attr |= ATTR_BLINK;
2981
2982                 if (term->use_bce)
2983                     term->erase_char = (' ' | ATTR_ASCII |
2984                                         (term->curr_attr &
2985                                          (ATTR_FGMASK | ATTR_BGMASK)));
2986                 break;
2987 #endif
2988               default: break;          /* placate gcc warning about enum use */
2989             }
2990         if (term->selstate != NO_SELECTION) {
2991             pos cursplus = term->curs;
2992             incpos(cursplus);
2993             check_selection(term, term->curs, cursplus);
2994         }
2995     }
2996
2997     term_print_flush(term);
2998 }
2999
3000 #if 0
3001 /*
3002  * Compare two lines to determine whether they are sufficiently
3003  * alike to scroll-optimise one to the other. Return the degree of
3004  * similarity.
3005  */
3006 static int linecmp(Terminal *term, unsigned long *a, unsigned long *b)
3007 {
3008     int i, n;
3009
3010     for (i = n = 0; i < term->cols; i++)
3011         n += (*a++ == *b++);
3012     return n;
3013 }
3014 #endif
3015
3016 /*
3017  * Given a context, update the window. Out of paranoia, we don't
3018  * allow WM_PAINT responses to do scrolling optimisations.
3019  */
3020 static void do_paint(Terminal *term, Context ctx, int may_optimise)
3021 {
3022     int i, j, our_curs_y, our_curs_x;
3023     unsigned long rv, cursor;
3024     pos scrpos;
3025     char ch[1024];
3026     long cursor_background = ERASE_CHAR;
3027     unsigned long ticks;
3028
3029     /*
3030      * Check the visual bell state.
3031      */
3032     if (term->in_vbell) {
3033         ticks = GETTICKCOUNT();
3034         if (ticks - term->vbell_startpoint >= VBELL_TIMEOUT)
3035             term->in_vbell = FALSE;
3036    }
3037
3038     rv = (!term->rvideo ^ !term->in_vbell ? ATTR_REVERSE : 0);
3039
3040     /* Depends on:
3041      * screen array, disptop, scrtop,
3042      * selection, rv,
3043      * cfg.blinkpc, blink_is_real, tblinker,
3044      * curs.y, curs.x, blinker, cfg.blink_cur, cursor_on, has_focus, wrapnext
3045      */
3046
3047     /* Has the cursor position or type changed ? */
3048     if (term->cursor_on) {
3049         if (term->has_focus) {
3050             if (term->blinker || !term->cfg.blink_cur)
3051                 cursor = TATTR_ACTCURS;
3052             else
3053                 cursor = 0;
3054         } else
3055             cursor = TATTR_PASCURS;
3056         if (term->wrapnext)
3057             cursor |= TATTR_RIGHTCURS;
3058     } else
3059         cursor = 0;
3060     our_curs_y = term->curs.y - term->disptop;
3061     {
3062         /*
3063          * Adjust the cursor position in the case where it's
3064          * resting on the right-hand half of a CJK wide character.
3065          * xterm's behaviour here, which seems adequate to me, is
3066          * to display the cursor covering the _whole_ character,
3067          * exactly as if it were one space to the left.
3068          */
3069         unsigned long *ldata = lineptr(term->curs.y);
3070         our_curs_x = term->curs.x;
3071         if (our_curs_x > 0 &&
3072             (ldata[our_curs_x] & (CHAR_MASK | CSET_MASK)) == UCSWIDE)
3073             our_curs_x--;
3074     }
3075
3076     if (term->dispcurs && (term->curstype != cursor ||
3077                            term->dispcurs !=
3078                            term->disptext + our_curs_y * (term->cols + 1) +
3079                            our_curs_x)) {
3080         if (term->dispcurs > term->disptext &&
3081             (*term->dispcurs & (CHAR_MASK | CSET_MASK)) == UCSWIDE)
3082             term->dispcurs[-1] |= ATTR_INVALID;
3083         if ( (term->dispcurs[1] & (CHAR_MASK | CSET_MASK)) == UCSWIDE)
3084             term->dispcurs[1] |= ATTR_INVALID;
3085         *term->dispcurs |= ATTR_INVALID;
3086         term->curstype = 0;
3087     }
3088     term->dispcurs = NULL;
3089
3090     /* The normal screen data */
3091     for (i = 0; i < term->rows; i++) {
3092         unsigned long *ldata;
3093         int lattr;
3094         int idx, dirty_line, dirty_run, selected;
3095         unsigned long attr = 0;
3096         int updated_line = 0;
3097         int start = 0;
3098         int ccount = 0;
3099         int last_run_dirty = 0;
3100
3101         scrpos.y = i + term->disptop;
3102         ldata = lineptr(scrpos.y);
3103         lattr = (ldata[term->cols] & LATTR_MODE);
3104
3105         idx = i * (term->cols + 1);
3106         dirty_run = dirty_line = (ldata[term->cols] !=
3107                                   term->disptext[idx + term->cols]);
3108         term->disptext[idx + term->cols] = ldata[term->cols];
3109
3110         for (j = 0; j < term->cols; j++, idx++) {
3111             unsigned long tattr, tchar;
3112             unsigned long *d = ldata + j;
3113             int break_run;
3114             scrpos.x = j;
3115
3116             tchar = (*d & (CHAR_MASK | CSET_MASK));
3117             tattr = (*d & (ATTR_MASK ^ CSET_MASK));
3118             switch (tchar & CSET_MASK) {
3119               case ATTR_ASCII:
3120                 tchar = term->ucsdata->unitab_line[tchar & 0xFF];
3121                 break;
3122               case ATTR_LINEDRW:
3123                 tchar = term->ucsdata->unitab_xterm[tchar & 0xFF];
3124                 break;
3125               case ATTR_SCOACS:
3126                 tchar = term->ucsdata->unitab_scoacs[tchar&0xFF];
3127                 break;
3128             }
3129             tattr |= (tchar & CSET_MASK);
3130             tchar &= CHAR_MASK;
3131             if ((d[1] & (CHAR_MASK | CSET_MASK)) == UCSWIDE)
3132                     tattr |= ATTR_WIDE;
3133
3134             /* Video reversing things */
3135             if (term->selstate == DRAGGING || term->selstate == SELECTED) {
3136                 if (term->seltype == LEXICOGRAPHIC)
3137                     selected = (posle(term->selstart, scrpos) &&
3138                                 poslt(scrpos, term->selend));
3139                 else
3140                     selected = (posPle(term->selstart, scrpos) &&
3141                                 posPlt(scrpos, term->selend));
3142             } else
3143                 selected = FALSE;
3144             tattr = (tattr ^ rv
3145                      ^ (selected ? ATTR_REVERSE : 0));
3146
3147             /* 'Real' blinking ? */
3148             if (term->blink_is_real && (tattr & ATTR_BLINK)) {
3149                 if (term->has_focus && term->tblinker) {
3150                     tchar = ' ';
3151                     tattr &= ~CSET_MASK;
3152                     tattr |= ATTR_ACP;
3153                 }
3154                 tattr &= ~ATTR_BLINK;
3155             }
3156
3157             /*
3158              * Check the font we'll _probably_ be using to see if
3159              * the character is wide when we don't want it to be.
3160              */
3161             if ((tchar | tattr) != (term->disptext[idx]& ~ATTR_NARROW)) {
3162                 if ((tattr & ATTR_WIDE) == 0 &&
3163                     char_width(ctx, (tchar | tattr) & 0xFFFF) == 2)
3164                     tattr |= ATTR_NARROW;
3165             } else if (term->disptext[idx]&ATTR_NARROW)
3166                 tattr |= ATTR_NARROW;
3167
3168             /* Cursor here ? Save the 'background' */
3169             if (i == our_curs_y && j == our_curs_x) {
3170                 cursor_background = tattr | tchar;
3171                 term->dispcurs = term->disptext + idx;
3172             }
3173
3174             if ((term->disptext[idx] ^ tattr) & ATTR_WIDE)
3175                 dirty_line = TRUE;
3176
3177             break_run = (((tattr ^ attr) & term->attr_mask) ||
3178                 j - start >= sizeof(ch));
3179
3180             /* Special hack for VT100 Linedraw glyphs */
3181             if ((attr & CSET_MASK) == 0x2300 && tchar >= 0xBA
3182                 && tchar <= 0xBD) break_run = TRUE;
3183
3184             if (!term->ucsdata->dbcs_screenfont && !dirty_line) {
3185                 if ((tchar | tattr) == term->disptext[idx])
3186                     break_run = TRUE;
3187                 else if (!dirty_run && ccount == 1)
3188                     break_run = TRUE;
3189             }
3190
3191             if (break_run) {
3192                 if ((dirty_run || last_run_dirty) && ccount > 0) {
3193                     do_text(ctx, start, i, ch, ccount, attr, lattr);
3194                     updated_line = 1;
3195                 }
3196                 start = j;
3197                 ccount = 0;
3198                 attr = tattr;
3199                 if (term->ucsdata->dbcs_screenfont)
3200                     last_run_dirty = dirty_run;
3201                 dirty_run = dirty_line;
3202             }
3203
3204             if ((tchar | tattr) != term->disptext[idx])
3205                 dirty_run = TRUE;
3206             ch[ccount++] = (char) tchar;
3207             term->disptext[idx] = tchar | tattr;
3208
3209             /* If it's a wide char step along to the next one. */
3210             if (tattr & ATTR_WIDE) {
3211                 if (++j < term->cols) {
3212                     idx++;
3213                     d++;
3214                     /*
3215                      * By construction above, the cursor should not
3216                      * be on the right-hand half of this character.
3217                      * Ever.
3218                      */
3219                     assert(!(i == our_curs_y && j == our_curs_x));
3220                     if (term->disptext[idx] != *d)
3221                         dirty_run = TRUE;
3222                     term->disptext[idx] = *d;
3223                 }
3224             }
3225         }
3226         if (dirty_run && ccount > 0) {
3227             do_text(ctx, start, i, ch, ccount, attr, lattr);
3228             updated_line = 1;
3229         }
3230
3231         /* Cursor on this line ? (and changed) */
3232         if (i == our_curs_y && (term->curstype != cursor || updated_line)) {
3233             ch[0] = (char) (cursor_background & CHAR_MASK);
3234             attr = (cursor_background & ATTR_MASK) | cursor;
3235             do_cursor(ctx, our_curs_x, i, ch, 1, attr, lattr);
3236             term->curstype = cursor;
3237         }
3238     }
3239 }
3240
3241 /*
3242  * Flick the switch that says if blinking things should be shown or hidden.
3243  */
3244
3245 void term_blink(Terminal *term, int flg)
3246 {
3247     long now, blink_diff;
3248
3249     now = GETTICKCOUNT();
3250     blink_diff = now - term->last_tblink;
3251
3252     /* Make sure the text blinks no more than 2Hz; we'll use 0.45 s period. */
3253     if (blink_diff < 0 || blink_diff > (TICKSPERSEC * 9 / 20)) {
3254         term->last_tblink = now;
3255         term->tblinker = !term->tblinker;
3256     }
3257
3258     if (flg) {
3259         term->blinker = 1;
3260         term->last_blink = now;
3261         return;
3262     }
3263
3264     blink_diff = now - term->last_blink;
3265
3266     /* Make sure the cursor blinks no faster than system blink rate */
3267     if (blink_diff >= 0 && blink_diff < (long) CURSORBLINK)
3268         return;
3269
3270     term->last_blink = now;
3271     term->blinker = !term->blinker;
3272 }
3273
3274 /*
3275  * Invalidate the whole screen so it will be repainted in full.
3276  */
3277 void term_invalidate(Terminal *term)
3278 {
3279     int i;
3280
3281     for (i = 0; i < term->rows * (term->cols + 1); i++)
3282         term->disptext[i] = ATTR_INVALID;
3283 }
3284
3285 /*
3286  * Paint the window in response to a WM_PAINT message.
3287  */
3288 void term_paint(Terminal *term, Context ctx,
3289                 int left, int top, int right, int bottom, int immediately)
3290 {
3291     int i, j;
3292     if (left < 0) left = 0;
3293     if (top < 0) top = 0;
3294     if (right >= term->cols) right = term->cols-1;
3295     if (bottom >= term->rows) bottom = term->rows-1;
3296
3297     for (i = top; i <= bottom && i < term->rows; i++) {
3298         if ((term->disptext[i * (term->cols + 1) + term->cols] &
3299              LATTR_MODE) == LATTR_NORM)
3300             for (j = left; j <= right && j < term->cols; j++)
3301                 term->disptext[i * (term->cols + 1) + j] = ATTR_INVALID;
3302         else
3303             for (j = left / 2; j <= right / 2 + 1 && j < term->cols; j++)
3304                 term->disptext[i * (term->cols + 1) + j] = ATTR_INVALID;
3305     }
3306
3307     /* This should happen soon enough, also for some reason it sometimes
3308      * fails to actually do anything when re-sizing ... painting the wrong
3309      * window perhaps ?
3310      */
3311     if (immediately)
3312         do_paint (term, ctx, FALSE);
3313 }
3314
3315 /*
3316  * Attempt to scroll the scrollback. The second parameter gives the
3317  * position we want to scroll to; the first is +1 to denote that
3318  * this position is relative to the beginning of the scrollback, -1
3319  * to denote it is relative to the end, and 0 to denote that it is
3320  * relative to the current position.
3321  */
3322 void term_scroll(Terminal *term, int rel, int where)
3323 {
3324     int sbtop = -count234(term->scrollback);
3325 #ifdef OPTIMISE_SCROLL
3326     int olddisptop = term->disptop;
3327     int shift;
3328 #endif /* OPTIMISE_SCROLL */
3329
3330     term->disptop = (rel < 0 ? 0 : rel > 0 ? sbtop : term->disptop) + where;
3331     if (term->disptop < sbtop)
3332         term->disptop = sbtop;
3333     if (term->disptop > 0)
3334         term->disptop = 0;
3335     update_sbar(term);
3336 #ifdef OPTIMISE_SCROLL
3337     shift = (term->disptop - olddisptop);
3338     if (shift < term->rows && shift > -term->rows)
3339         scroll_display(term, 0, term->rows - 1, shift);
3340 #endif /* OPTIMISE_SCROLL */
3341     term_update(term);
3342 }
3343
3344 static void clipme(Terminal *term, pos top, pos bottom, int rect)
3345 {
3346     wchar_t *workbuf;
3347     wchar_t *wbptr;                    /* where next char goes within workbuf */
3348     int old_top_x;
3349     int wblen = 0;                     /* workbuf len */
3350     int buflen;                        /* amount of memory allocated to workbuf */
3351
3352     buflen = 5120;                     /* Default size */
3353     workbuf = smalloc(buflen * sizeof(wchar_t));
3354     wbptr = workbuf;                   /* start filling here */
3355     old_top_x = top.x;                 /* needed for rect==1 */
3356
3357     while (poslt(top, bottom)) {
3358         int nl = FALSE;
3359         unsigned long *ldata = lineptr(top.y);
3360         pos nlpos;
3361
3362         /*
3363          * nlpos will point at the maximum position on this line we
3364          * should copy up to. So we start it at the end of the
3365          * line...
3366          */
3367         nlpos.y = top.y;
3368         nlpos.x = term->cols;
3369
3370         /*
3371          * ... move it backwards if there's unused space at the end
3372          * of the line (and also set `nl' if this is the case,
3373          * because in normal selection mode this means we need a
3374          * newline at the end)...
3375          */
3376         if (!(ldata[term->cols] & LATTR_WRAPPED)) {
3377             while (((ldata[nlpos.x - 1] & 0xFF) == 0x20 ||
3378                     (DIRECT_CHAR(ldata[nlpos.x - 1]) &&
3379                      (ldata[nlpos.x - 1] & CHAR_MASK) == 0x20))
3380                    && poslt(top, nlpos))
3381                 decpos(nlpos);
3382             if (poslt(nlpos, bottom))
3383                 nl = TRUE;
3384         } else if (ldata[term->cols] & LATTR_WRAPPED2) {
3385             /* Ignore the last char on the line in a WRAPPED2 line. */
3386             decpos(nlpos);
3387         }
3388
3389         /*
3390          * ... and then clip it to the terminal x coordinate if
3391          * we're doing rectangular selection. (In this case we
3392          * still did the above, so that copying e.g. the right-hand
3393          * column from a table doesn't fill with spaces on the
3394          * right.)
3395          */
3396         if (rect) {
3397             if (nlpos.x > bottom.x)
3398                 nlpos.x = bottom.x;
3399             nl = (top.y < bottom.y);
3400         }
3401
3402         while (poslt(top, bottom) && poslt(top, nlpos)) {
3403 #if 0
3404             char cbuf[16], *p;
3405             sprintf(cbuf, "<U+%04x>", (ldata[top.x] & 0xFFFF));
3406 #else
3407             wchar_t cbuf[16], *p;
3408             int uc = (ldata[top.x] & 0xFFFF);
3409             int set, c;
3410
3411             if (uc == UCSWIDE) {
3412                 top.x++;
3413                 continue;
3414             }
3415
3416             switch (uc & CSET_MASK) {
3417               case ATTR_LINEDRW:
3418                 if (!term->cfg.rawcnp) {
3419                     uc = term->ucsdata->unitab_xterm[uc & 0xFF];
3420                     break;
3421                 }
3422               case ATTR_ASCII:
3423                 uc = term->ucsdata->unitab_line[uc & 0xFF];
3424                 break;
3425               case ATTR_SCOACS:
3426                 uc = term->ucsdata->unitab_scoacs[uc&0xFF];
3427                 break;
3428             }
3429             switch (uc & CSET_MASK) {
3430               case ATTR_ACP:
3431                 uc = term->ucsdata->unitab_font[uc & 0xFF];
3432                 break;
3433               case ATTR_OEMCP:
3434                 uc = term->ucsdata->unitab_oemcp[uc & 0xFF];
3435                 break;
3436             }
3437
3438             set = (uc & CSET_MASK);
3439             c = (uc & CHAR_MASK);
3440             cbuf[0] = uc;
3441             cbuf[1] = 0;
3442
3443             if (DIRECT_FONT(uc)) {
3444                 if (c >= ' ' && c != 0x7F) {
3445                     char buf[4];
3446                     WCHAR wbuf[4];
3447                     int rv;
3448                     if (is_dbcs_leadbyte(term->ucsdata->font_codepage, (BYTE) c)) {
3449                         buf[0] = c;
3450                         buf[1] = (char) (0xFF & ldata[top.x + 1]);
3451                         rv = mb_to_wc(term->ucsdata->font_codepage, 0, buf, 2, wbuf, 4);
3452                         top.x++;
3453                     } else {
3454                         buf[0] = c;
3455                         rv = mb_to_wc(term->ucsdata->font_codepage, 0, buf, 1, wbuf, 4);
3456                     }
3457
3458                     if (rv > 0) {
3459                         memcpy(cbuf, wbuf, rv * sizeof(wchar_t));
3460                         cbuf[rv] = 0;
3461                     }
3462                 }
3463             }
3464 #endif
3465
3466             for (p = cbuf; *p; p++) {
3467                 /* Enough overhead for trailing NL and nul */
3468                 if (wblen >= buflen - 16) {
3469                     workbuf =
3470                         srealloc(workbuf,
3471                                  sizeof(wchar_t) * (buflen += 100));
3472                     wbptr = workbuf + wblen;
3473                 }
3474                 wblen++;
3475                 *wbptr++ = *p;
3476             }
3477             top.x++;
3478         }
3479         if (nl) {
3480             int i;
3481             for (i = 0; i < sel_nl_sz; i++) {
3482                 wblen++;
3483                 *wbptr++ = sel_nl[i];
3484             }
3485         }
3486         top.y++;
3487         top.x = rect ? old_top_x : 0;
3488     }
3489 #if SELECTION_NUL_TERMINATED
3490     wblen++;
3491     *wbptr++ = 0;
3492 #endif
3493     write_clip(term->frontend, workbuf, wblen, FALSE); /* transfer to clipbd */
3494     if (buflen > 0)                    /* indicates we allocated this buffer */
3495         sfree(workbuf);
3496 }
3497
3498 void term_copyall(Terminal *term)
3499 {
3500     pos top;
3501     top.y = -count234(term->scrollback);
3502     top.x = 0;
3503     clipme(term, top, term->curs, 0);
3504 }
3505
3506 /*
3507  * The wordness array is mainly for deciding the disposition of the
3508  * US-ASCII characters.
3509  */
3510 static int wordtype(Terminal *term, int uc)
3511 {
3512     struct ucsword {
3513         int start, end, ctype;
3514     };
3515     static const struct ucsword ucs_words[] = {
3516         {
3517         128, 160, 0}, {
3518         161, 191, 1}, {
3519         215, 215, 1}, {
3520         247, 247, 1}, {
3521         0x037e, 0x037e, 1},            /* Greek question mark */
3522         {
3523         0x0387, 0x0387, 1},            /* Greek ano teleia */
3524         {
3525         0x055a, 0x055f, 1},            /* Armenian punctuation */
3526         {
3527         0x0589, 0x0589, 1},            /* Armenian full stop */
3528         {
3529         0x0700, 0x070d, 1},            /* Syriac punctuation */
3530         {
3531         0x104a, 0x104f, 1},            /* Myanmar punctuation */
3532         {
3533         0x10fb, 0x10fb, 1},            /* Georgian punctuation */
3534         {
3535         0x1361, 0x1368, 1},            /* Ethiopic punctuation */
3536         {
3537         0x166d, 0x166e, 1},            /* Canadian Syl. punctuation */
3538         {
3539         0x17d4, 0x17dc, 1},            /* Khmer punctuation */
3540         {
3541         0x1800, 0x180a, 1},            /* Mongolian punctuation */
3542         {
3543         0x2000, 0x200a, 0},            /* Various spaces */
3544         {
3545         0x2070, 0x207f, 2},            /* superscript */
3546         {
3547         0x2080, 0x208f, 2},            /* subscript */
3548         {
3549         0x200b, 0x27ff, 1},            /* punctuation and symbols */
3550         {
3551         0x3000, 0x3000, 0},            /* ideographic space */
3552         {
3553         0x3001, 0x3020, 1},            /* ideographic punctuation */
3554         {
3555         0x303f, 0x309f, 3},            /* Hiragana */
3556         {
3557         0x30a0, 0x30ff, 3},            /* Katakana */
3558         {
3559         0x3300, 0x9fff, 3},            /* CJK Ideographs */
3560         {
3561         0xac00, 0xd7a3, 3},            /* Hangul Syllables */
3562         {
3563         0xf900, 0xfaff, 3},            /* CJK Ideographs */
3564         {
3565         0xfe30, 0xfe6b, 1},            /* punctuation forms */
3566         {
3567         0xff00, 0xff0f, 1},            /* half/fullwidth ASCII */
3568         {
3569         0xff1a, 0xff20, 1},            /* half/fullwidth ASCII */
3570         {
3571         0xff3b, 0xff40, 1},            /* half/fullwidth ASCII */
3572         {
3573         0xff5b, 0xff64, 1},            /* half/fullwidth ASCII */
3574         {
3575         0xfff0, 0xffff, 0},            /* half/fullwidth ASCII */
3576         {
3577         0, 0, 0}
3578     };
3579     const struct ucsword *wptr;
3580
3581     uc &= (CSET_MASK | CHAR_MASK);
3582
3583     switch (uc & CSET_MASK) {
3584       case ATTR_LINEDRW:
3585         uc = term->ucsdata->unitab_xterm[uc & 0xFF];
3586         break;
3587       case ATTR_ASCII:
3588         uc = term->ucsdata->unitab_line[uc & 0xFF];
3589         break;
3590       case ATTR_SCOACS:
3591         uc = term->ucsdata->unitab_scoacs[uc&0xFF];
3592         break;
3593     }
3594     switch (uc & CSET_MASK) {
3595       case ATTR_ACP:
3596         uc = term->ucsdata->unitab_font[uc & 0xFF];
3597         break;
3598       case ATTR_OEMCP:
3599         uc = term->ucsdata->unitab_oemcp[uc & 0xFF];
3600         break;
3601     }
3602
3603     /* For DBCS font's I can't do anything usefull. Even this will sometimes
3604      * fail as there's such a thing as a double width space. :-(
3605      */
3606     if (term->ucsdata->dbcs_screenfont &&
3607         term->ucsdata->font_codepage == term->ucsdata->line_codepage)
3608         return (uc != ' ');
3609
3610     if (uc < 0x80)
3611         return term->wordness[uc];
3612
3613     for (wptr = ucs_words; wptr->start; wptr++) {
3614         if (uc >= wptr->start && uc <= wptr->end)
3615             return wptr->ctype;
3616     }
3617
3618     return 2;
3619 }
3620
3621 /*
3622  * Spread the selection outwards according to the selection mode.
3623  */
3624 static pos sel_spread_half(Terminal *term, pos p, int dir)
3625 {
3626     unsigned long *ldata;
3627     short wvalue;
3628     int topy = -count234(term->scrollback);
3629
3630     ldata = lineptr(p.y);
3631
3632     switch (term->selmode) {
3633       case SM_CHAR:
3634         /*
3635          * In this mode, every character is a separate unit, except
3636          * for runs of spaces at the end of a non-wrapping line.
3637          */
3638         if (!(ldata[term->cols] & LATTR_WRAPPED)) {
3639             unsigned long *q = ldata + term->cols;
3640             while (q > ldata && (q[-1] & CHAR_MASK) == 0x20)
3641                 q--;
3642             if (q == ldata + term->cols)
3643                 q--;
3644             if (p.x >= q - ldata)
3645                 p.x = (dir == -1 ? q - ldata : term->cols - 1);
3646         }
3647         break;
3648       case SM_WORD:
3649         /*
3650          * In this mode, the units are maximal runs of characters
3651          * whose `wordness' has the same value.
3652          */
3653         wvalue = wordtype(term, UCSGET(ldata, p.x));
3654         if (dir == +1) {
3655             while (1) {
3656                 int maxcols = (ldata[term->cols] & LATTR_WRAPPED2 ?
3657                                term->cols-1 : term->cols);
3658                 if (p.x < maxcols-1) {
3659                     if (wordtype(term, UCSGET(ldata, p.x + 1)) == wvalue)
3660                         p.x++;
3661                     else
3662                         break;
3663                 } else {
3664                     if (ldata[term->cols] & LATTR_WRAPPED) {
3665                         unsigned long *ldata2;
3666                         ldata2 = lineptr(p.y+1);
3667                         if (wordtype(term, UCSGET(ldata2, 0)) == wvalue) {
3668                             p.x = 0;
3669                             p.y++;
3670                             ldata = ldata2;
3671                         } else
3672                             break;
3673                     } else
3674                         break;
3675                 }
3676             }
3677         } else {
3678             while (1) {
3679                 if (p.x > 0) {
3680                     if (wordtype(term, UCSGET(ldata, p.x - 1)) == wvalue)
3681                         p.x--;
3682                     else
3683                         break;
3684                 } else {
3685                     unsigned long *ldata2;
3686                     int maxcols;
3687                     if (p.y <= topy)
3688                         break;
3689                     ldata2 = lineptr(p.y-1);
3690                     maxcols = (ldata2[term->cols] & LATTR_WRAPPED2 ?
3691                               term->cols-1 : term->cols);
3692                     if (ldata2[term->cols] & LATTR_WRAPPED) {
3693                         if (wordtype(term, UCSGET(ldata2, maxcols-1))
3694                             == wvalue) {
3695                             p.x = maxcols-1;
3696                             p.y--;
3697                             ldata = ldata2;
3698                         } else
3699                             break;
3700                     } else
3701                         break;
3702                 }
3703             }
3704         }
3705         break;
3706       case SM_LINE:
3707         /*
3708          * In this mode, every line is a unit.
3709          */
3710         p.x = (dir == -1 ? 0 : term->cols - 1);
3711         break;
3712     }
3713     return p;
3714 }
3715
3716 static void sel_spread(Terminal *term)
3717 {
3718     if (term->seltype == LEXICOGRAPHIC) {
3719         term->selstart = sel_spread_half(term, term->selstart, -1);
3720         decpos(term->selend);
3721         term->selend = sel_spread_half(term, term->selend, +1);
3722         incpos(term->selend);
3723     }
3724 }
3725
3726 void term_do_paste(Terminal *term)
3727 {
3728     wchar_t *data;
3729     int len;
3730
3731     get_clip(term->frontend, &data, &len);
3732     if (data && len > 0) {
3733         wchar_t *p, *q;
3734
3735         term_seen_key_event(term);     /* pasted data counts */
3736
3737         if (term->paste_buffer)
3738             sfree(term->paste_buffer);
3739         term->paste_pos = term->paste_hold = term->paste_len = 0;
3740         term->paste_buffer = smalloc(len * sizeof(wchar_t));
3741
3742         p = q = data;
3743         while (p < data + len) {
3744             while (p < data + len &&
3745                    !(p <= data + len - sel_nl_sz &&
3746                      !memcmp(p, sel_nl, sizeof(sel_nl))))
3747                 p++;
3748
3749             {
3750                 int i;
3751                 for (i = 0; i < p - q; i++) {
3752                     term->paste_buffer[term->paste_len++] = q[i];
3753                 }
3754             }
3755
3756             if (p <= data + len - sel_nl_sz &&
3757                 !memcmp(p, sel_nl, sizeof(sel_nl))) {
3758                 term->paste_buffer[term->paste_len++] = '\015';
3759                 p += sel_nl_sz;
3760             }
3761             q = p;
3762         }
3763
3764         /* Assume a small paste will be OK in one go. */
3765         if (term->paste_len < 256) {
3766             if (term->ldisc)
3767                 luni_send(term->ldisc, term->paste_buffer, term->paste_len, 0);
3768             if (term->paste_buffer)
3769                 sfree(term->paste_buffer);
3770             term->paste_buffer = 0;
3771             term->paste_pos = term->paste_hold = term->paste_len = 0;
3772         }
3773     }
3774     get_clip(term->frontend, NULL, NULL);
3775 }
3776
3777 void term_mouse(Terminal *term, Mouse_Button b, Mouse_Action a, int x, int y,
3778                 int shift, int ctrl, int alt)
3779 {
3780     pos selpoint;
3781     unsigned long *ldata;
3782     int raw_mouse = (term->xterm_mouse &&
3783                      !term->cfg.no_mouse_rep &&
3784                      !(term->cfg.mouse_override && shift));
3785     int default_seltype;
3786
3787     if (y < 0) {
3788         y = 0;
3789         if (a == MA_DRAG && !raw_mouse)
3790             term_scroll(term, 0, -1);
3791     }
3792     if (y >= term->rows) {
3793         y = term->rows - 1;
3794         if (a == MA_DRAG && !raw_mouse)
3795             term_scroll(term, 0, +1);
3796     }
3797     if (x < 0) {
3798         if (y > 0) {
3799             x = term->cols - 1;
3800             y--;
3801         } else
3802             x = 0;
3803     }
3804     if (x >= term->cols)
3805         x = term->cols - 1;
3806
3807     selpoint.y = y + term->disptop;
3808     selpoint.x = x;
3809     ldata = lineptr(selpoint.y);
3810     if ((ldata[term->cols] & LATTR_MODE) != LATTR_NORM)
3811         selpoint.x /= 2;
3812
3813     if (raw_mouse) {
3814         int encstate = 0, r, c;
3815         char abuf[16];
3816
3817         if (term->ldisc) {
3818
3819             switch (b) {
3820               case MBT_LEFT:
3821                 encstate = 0x20;               /* left button down */
3822                 break;
3823               case MBT_MIDDLE:
3824                 encstate = 0x21;
3825                 break;
3826               case MBT_RIGHT:
3827                 encstate = 0x22;
3828                 break;
3829               case MBT_WHEEL_UP:
3830                 encstate = 0x60;
3831                 break;
3832               case MBT_WHEEL_DOWN:
3833                 encstate = 0x61;
3834                 break;
3835               default: break;          /* placate gcc warning about enum use */
3836             }
3837             switch (a) {
3838               case MA_DRAG:
3839                 if (term->xterm_mouse == 1)
3840                     return;
3841                 encstate += 0x20;
3842                 break;
3843               case MA_RELEASE:
3844                 encstate = 0x23;
3845                 term->mouse_is_down = 0;
3846                 break;
3847               case MA_CLICK:
3848                 if (term->mouse_is_down == b)
3849                     return;
3850                 term->mouse_is_down = b;
3851                 break;
3852               default: break;          /* placate gcc warning about enum use */
3853             }
3854             if (shift)
3855                 encstate += 0x04;
3856             if (ctrl)
3857                 encstate += 0x10;
3858             r = y + 33;
3859             c = x + 33;
3860
3861             sprintf(abuf, "\033[M%c%c%c", encstate, c, r);
3862             ldisc_send(term->ldisc, abuf, 6, 0);
3863         }
3864         return;
3865     }
3866
3867     b = translate_button(term->frontend, b);
3868
3869     /*
3870      * Set the selection type (rectangular or normal) at the start
3871      * of a selection attempt, from the state of Alt.
3872      */
3873     if (!alt ^ !term->cfg.rect_select)
3874         default_seltype = RECTANGULAR;
3875     else
3876         default_seltype = LEXICOGRAPHIC;
3877
3878     if (term->selstate == NO_SELECTION) {
3879         term->seltype = default_seltype;
3880     }
3881
3882     if (b == MBT_SELECT && a == MA_CLICK) {
3883         deselect(term);
3884         term->selstate = ABOUT_TO;
3885         term->seltype = default_seltype;
3886         term->selanchor = selpoint;
3887         term->selmode = SM_CHAR;
3888     } else if (b == MBT_SELECT && (a == MA_2CLK || a == MA_3CLK)) {
3889         deselect(term);
3890         term->selmode = (a == MA_2CLK ? SM_WORD : SM_LINE);
3891         term->selstate = DRAGGING;
3892         term->selstart = term->selanchor = selpoint;
3893         term->selend = term->selstart;
3894         incpos(term->selend);
3895         sel_spread(term);
3896     } else if ((b == MBT_SELECT && a == MA_DRAG) ||
3897                (b == MBT_EXTEND && a != MA_RELEASE)) {
3898         if (term->selstate == ABOUT_TO && poseq(term->selanchor, selpoint))
3899             return;
3900         if (b == MBT_EXTEND && a != MA_DRAG && term->selstate == SELECTED) {
3901             if (term->seltype == LEXICOGRAPHIC) {
3902                 /*
3903                  * For normal selection, we extend by moving
3904                  * whichever end of the current selection is closer
3905                  * to the mouse.
3906                  */
3907                 if (posdiff(selpoint, term->selstart) <
3908                     posdiff(term->selend, term->selstart) / 2) {
3909                     term->selanchor = term->selend;
3910                     decpos(term->selanchor);
3911                 } else {
3912                     term->selanchor = term->selstart;
3913                 }
3914             } else {
3915                 /*
3916                  * For rectangular selection, we have a choice of
3917                  * _four_ places to put selanchor and selpoint: the
3918                  * four corners of the selection.
3919                  */
3920                 if (2*selpoint.x < term->selstart.x + term->selend.x)
3921                     term->selanchor.x = term->selend.x-1;
3922                 else
3923                     term->selanchor.x = term->selstart.x;
3924
3925                 if (2*selpoint.y < term->selstart.y + term->selend.y)
3926                     term->selanchor.y = term->selend.y;
3927                 else
3928                     term->selanchor.y = term->selstart.y;
3929             }
3930             term->selstate = DRAGGING;
3931         }
3932         if (term->selstate != ABOUT_TO && term->selstate != DRAGGING)
3933             term->selanchor = selpoint;
3934         term->selstate = DRAGGING;
3935         if (term->seltype == LEXICOGRAPHIC) {
3936             /*
3937              * For normal selection, we set (selstart,selend) to
3938              * (selpoint,selanchor) in some order.
3939              */
3940             if (poslt(selpoint, term->selanchor)) {
3941                 term->selstart = selpoint;
3942                 term->selend = term->selanchor;
3943                 incpos(term->selend);
3944             } else {
3945                 term->selstart = term->selanchor;
3946                 term->selend = selpoint;
3947                 incpos(term->selend);
3948             }
3949         } else {
3950             /*
3951              * For rectangular selection, we may need to
3952              * interchange x and y coordinates (if the user has
3953              * dragged in the -x and +y directions, or vice versa).
3954              */
3955             term->selstart.x = min(term->selanchor.x, selpoint.x);
3956             term->selend.x = 1+max(term->selanchor.x, selpoint.x);
3957             term->selstart.y = min(term->selanchor.y, selpoint.y);
3958             term->selend.y =   max(term->selanchor.y, selpoint.y);
3959         }
3960         sel_spread(term);
3961     } else if ((b == MBT_SELECT || b == MBT_EXTEND) && a == MA_RELEASE) {
3962         if (term->selstate == DRAGGING) {
3963             /*
3964              * We've completed a selection. We now transfer the
3965              * data to the clipboard.
3966              */
3967             clipme(term, term->selstart, term->selend,
3968                    (term->seltype == RECTANGULAR));
3969             term->selstate = SELECTED;
3970         } else
3971             term->selstate = NO_SELECTION;
3972     } else if (b == MBT_PASTE
3973                && (a == MA_CLICK
3974 #if MULTICLICK_ONLY_EVENT
3975                    || a == MA_2CLK || a == MA_3CLK
3976 #endif
3977                    )) {
3978         request_paste(term->frontend);
3979     }
3980
3981     term_update(term);
3982 }
3983
3984 void term_nopaste(Terminal *term)
3985 {
3986     if (term->paste_len == 0)
3987         return;
3988     sfree(term->paste_buffer);
3989     term->paste_buffer = NULL;
3990     term->paste_len = 0;
3991 }
3992
3993 int term_paste_pending(Terminal *term)
3994 {
3995     return term->paste_len != 0;
3996 }
3997
3998 void term_paste(Terminal *term)
3999 {
4000     long now, paste_diff;
4001
4002     if (term->paste_len == 0)
4003         return;
4004
4005     /* Don't wait forever to paste */
4006     if (term->paste_hold) {
4007         now = GETTICKCOUNT();
4008         paste_diff = now - term->last_paste;
4009         if (paste_diff >= 0 && paste_diff < 450)
4010             return;
4011     }
4012     term->paste_hold = 0;
4013
4014     while (term->paste_pos < term->paste_len) {
4015         int n = 0;
4016         while (n + term->paste_pos < term->paste_len) {
4017             if (term->paste_buffer[term->paste_pos + n++] == '\015')
4018                 break;
4019         }
4020         if (term->ldisc)
4021             luni_send(term->ldisc, term->paste_buffer + term->paste_pos, n, 0);
4022         term->paste_pos += n;
4023
4024         if (term->paste_pos < term->paste_len) {
4025             term->paste_hold = 1;
4026             return;
4027         }
4028     }
4029     sfree(term->paste_buffer);
4030     term->paste_buffer = NULL;
4031     term->paste_len = 0;
4032 }
4033
4034 static void deselect(Terminal *term)
4035 {
4036     term->selstate = NO_SELECTION;
4037     term->selstart.x = term->selstart.y = term->selend.x = term->selend.y = 0;
4038 }
4039
4040 void term_deselect(Terminal *term)
4041 {
4042     deselect(term);
4043     term_update(term);
4044 }
4045
4046 int term_ldisc(Terminal *term, int option)
4047 {
4048     if (option == LD_ECHO)
4049         return term->term_echoing;
4050     if (option == LD_EDIT)
4051         return term->term_editing;
4052     return FALSE;
4053 }
4054
4055 /*
4056  * from_backend(), to get data from the backend for the terminal.
4057  */
4058 int from_backend(void *vterm, int is_stderr, char *data, int len)
4059 {
4060     Terminal *term = (Terminal *)vterm;
4061
4062     assert(len > 0);
4063
4064     bufchain_add(&term->inbuf, data, len);
4065
4066     /*
4067      * term_out() always completely empties inbuf. Therefore,
4068      * there's no reason at all to return anything other than zero
4069      * from this function, because there _can't_ be a question of
4070      * the remote side needing to wait until term_out() has cleared
4071      * a backlog.
4072      *
4073      * This is a slightly suboptimal way to deal with SSH2 - in
4074      * principle, the window mechanism would allow us to continue
4075      * to accept data on forwarded ports and X connections even
4076      * while the terminal processing was going slowly - but we
4077      * can't do the 100% right thing without moving the terminal
4078      * processing into a separate thread, and that might hurt
4079      * portability. So we manage stdout buffering the old SSH1 way:
4080      * if the terminal processing goes slowly, the whole SSH
4081      * connection stops accepting data until it's ready.
4082      *
4083      * In practice, I can't imagine this causing serious trouble.
4084      */
4085     return 0;
4086 }
4087
4088 void term_provide_logctx(Terminal *term, void *logctx)
4089 {
4090     term->logctx = logctx;
4091 }