builtin-apply.c

   1 /*
   2  * apply.c
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  *
   6  * This applies patches on top of some (arbitrary) version of the SCM.
   7  *
   8  */
   9 #include <fnmatch.h>
  10 #include "cache.h"
  11 #include "cache-tree.h"
  12 #include "quote.h"
  13 #include "blob.h"
  14 #include "delta.h"
  15 #include "builtin.h"
  16
  17 /*
  18  *  --check turns on checking that the working tree matches the
  19  *    files that are being modified, but doesn't apply the patch
  20  *  --stat does just a diffstat, and doesn't actually apply
  21  *  --numstat does numeric diffstat, and doesn't actually apply
  22  *  --index-info shows the old and new index info for paths if available.
  23  *  --index updates the cache as well.
  24  *  --cached updates only the cache without ever touching the working tree.
  25  */
  26 static const char *prefix;
  27 static int prefix_length = -1;
  28 static int newfd = -1;
  29
  30 static int p_value = 1;
  31 static int allow_binary_replacement;
  32 static int check_index;
  33 static int write_index;
  34 static int cached;
  35 static int diffstat;
  36 static int numstat;
  37 static int summary;
  38 static int check;
  39 static int apply = 1;
  40 static int apply_in_reverse;
  41 static int apply_with_reject;
  42 static int no_add;
  43 static int show_index_info;
  44 static int line_termination = '\n';
  45 static unsigned long p_context = -1;
  46 static const char apply_usage[] =
  47 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|error|error-all|strip>] <patch>...";
  48
  49 static enum whitespace_eol {
  50         nowarn_whitespace,
  51         warn_on_whitespace,
  52         error_on_whitespace,
  53         strip_whitespace,
  54 } new_whitespace = warn_on_whitespace;
  55 static int whitespace_error;
  56 static int squelch_whitespace_errors = 5;
  57 static int applied_after_stripping;
  58 static const char *patch_input_file;
  59
  60 static void parse_whitespace_option(const char *option)
  61 {
  62         if (!option) {
  63                 new_whitespace = warn_on_whitespace;
  64                 return;
  65         }
  66         if (!strcmp(option, "warn")) {
  67                 new_whitespace = warn_on_whitespace;
  68                 return;
  69         }
  70         if (!strcmp(option, "nowarn")) {
  71                 new_whitespace = nowarn_whitespace;
  72                 return;
  73         }
  74         if (!strcmp(option, "error")) {
  75                 new_whitespace = error_on_whitespace;
  76                 return;
  77         }
  78         if (!strcmp(option, "error-all")) {
  79                 new_whitespace = error_on_whitespace;
  80                 squelch_whitespace_errors = 0;
  81                 return;
  82         }
  83         if (!strcmp(option, "strip")) {
  84                 new_whitespace = strip_whitespace;
  85                 return;
  86         }
  87         die("unrecognized whitespace option '%s'", option);
  88 }
  89
  90 static void set_default_whitespace_mode(const char *whitespace_option)
  91 {
  92         if (!whitespace_option && !apply_default_whitespace) {
  93                 new_whitespace = (apply
  94                                   ? warn_on_whitespace
  95                                   : nowarn_whitespace);
  96         }
  97 }
  98
  99 /*
 100  * For "diff-stat" like behaviour, we keep track of the biggest change
 101  * we've seen, and the longest filename. That allows us to do simple
 102  * scaling.
 103  */
 104 static int max_change, max_len;
 105
 106 /*
 107  * Various "current state", notably line numbers and what
 108  * file (and how) we're patching right now.. The "is_xxxx"
 109  * things are flags, where -1 means "don't know yet".
 110  */
 111 static int linenr = 1;
 112
 113 /*
 114  * This represents one "hunk" from a patch, starting with
 115  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 116  * patch text is pointed at by patch, and its byte length
 117  * is stored in size.  leading and trailing are the number
 118  * of context lines.
 119  */
 120 struct fragment {
 121         unsigned long leading, trailing;
 122         unsigned long oldpos, oldlines;
 123         unsigned long newpos, newlines;
 124         const char *patch;
 125         int size;
 126         int rejected;
 127         struct fragment *next;
 128 };
 129
 130 /*
 131  * When dealing with a binary patch, we reuse "leading" field
 132  * to store the type of the binary hunk, either deflated "delta"
 133  * or deflated "literal".
 134  */
 135 #define binary_patch_method leading
 136 #define BINARY_DELTA_DEFLATED   1
 137 #define BINARY_LITERAL_DEFLATED 2
 138
 139 struct patch {
 140         char *new_name, *old_name, *def_name;
 141         unsigned int old_mode, new_mode;
 142         int is_rename, is_copy, is_new, is_delete, is_binary;
 143         int rejected;
 144         unsigned long deflate_origlen;
 145         int lines_added, lines_deleted;
 146         int score;
 147         int inaccurate_eof:1;
 148         struct fragment *fragments;
 149         char *result;
 150         unsigned long resultsize;
 151         char old_sha1_prefix[41];
 152         char new_sha1_prefix[41];
 153         struct patch *next;
 154 };
 155
 156 #define CHUNKSIZE (8192)
 157 #define SLOP (16)
 158
 159 static void *read_patch_file(int fd, unsigned long *sizep)
 160 {
 161         unsigned long size = 0, alloc = CHUNKSIZE;
 162         void *buffer = xmalloc(alloc);
 163
 164         for (;;) {
 165                 int nr = alloc - size;
 166                 if (nr < 1024) {
 167                         alloc += CHUNKSIZE;
 168                         buffer = xrealloc(buffer, alloc);
 169                         nr = alloc - size;
 170                 }
 171                 nr = xread(fd, (char *) buffer + size, nr);
 172                 if (!nr)
 173                         break;
 174                 if (nr < 0)
 175                         die("git-apply: read returned %s", strerror(errno));
 176                 size += nr;
 177         }
 178         *sizep = size;
 179
 180         /*
 181          * Make sure that we have some slop in the buffer
 182          * so that we can do speculative "memcmp" etc, and
 183          * see to it that it is NUL-filled.
 184          */
 185         if (alloc < size + SLOP)
 186                 buffer = xrealloc(buffer, size + SLOP);
 187         memset((char *) buffer + size, 0, SLOP);
 188         return buffer;
 189 }
 190
 191 static unsigned long linelen(const char *buffer, unsigned long size)
 192 {
 193         unsigned long len = 0;
 194         while (size--) {
 195                 len++;
 196                 if (*buffer++ == '\n')
 197                         break;
 198         }
 199         return len;
 200 }
 201
 202 static int is_dev_null(const char *str)
 203 {
 204         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
 205 }
 206
 207 #define TERM_SPACE      1
 208 #define TERM_TAB        2
 209
 210 static int name_terminate(const char *name, int namelen, int c, int terminate)
 211 {
 212         if (c == ' ' && !(terminate & TERM_SPACE))
 213                 return 0;
 214         if (c == '\t' && !(terminate & TERM_TAB))
 215                 return 0;
 216
 217         return 1;
 218 }
 219
 220 static char * find_name(const char *line, char *def, int p_value, int terminate)
 221 {
 222         int len;
 223         const char *start = line;
 224         char *name;
 225
 226         if (*line == '"') {
 227                 /* Proposed "new-style" GNU patch/diff format; see
 228                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
 229                  */
 230                 name = unquote_c_style(line, NULL);
 231                 if (name) {
 232                         char *cp = name;
 233                         while (p_value) {
 234                                 cp = strchr(name, '/');
 235                                 if (!cp)
 236                                         break;
 237                                 cp++;
 238                                 p_value--;
 239                         }
 240                         if (cp) {
 241                                 /* name can later be freed, so we need
 242                                  * to memmove, not just return cp
 243                                  */
 244                                 memmove(name, cp, strlen(cp) + 1);
 245                                 free(def);
 246                                 return name;
 247                         }
 248                         else {
 249                                 free(name);
 250                                 name = NULL;
 251                         }
 252                 }
 253         }
 254
 255         for (;;) {
 256                 char c = *line;
 257
 258                 if (isspace(c)) {
 259                         if (c == '\n')
 260                                 break;
 261                         if (name_terminate(start, line-start, c, terminate))
 262                                 break;
 263                 }
 264                 line++;
 265                 if (c == '/' && !--p_value)
 266                         start = line;
 267         }
 268         if (!start)
 269                 return def;
 270         len = line - start;
 271         if (!len)
 272                 return def;
 273
 274         /*
 275          * Generally we prefer the shorter name, especially
 276          * if the other one is just a variation of that with
 277          * something else tacked on to the end (ie "file.orig"
 278          * or "file~").
 279          */
 280         if (def) {
 281                 int deflen = strlen(def);
 282                 if (deflen < len && !strncmp(start, def, deflen))
 283                         return def;
 284         }
 285
 286         name = xmalloc(len + 1);
 287         memcpy(name, start, len);
 288         name[len] = 0;
 289         free(def);
 290         return name;
 291 }
 292
 293 /*
 294  * Get the name etc info from the --/+++ lines of a traditional patch header
 295  *
 296  * NOTE! This hardcodes "-p1" behaviour in filename detection.
 297  *
 298  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 299  * files, we can happily check the index for a match, but for creating a
 300  * new file we should try to match whatever "patch" does. I have no idea.
 301  */
 302 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
 303 {
 304         char *name;
 305
 306         first += 4;     /* skip "--- " */
 307         second += 4;    /* skip "+++ " */
 308         if (is_dev_null(first)) {
 309                 patch->is_new = 1;
 310                 patch->is_delete = 0;
 311                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
 312                 patch->new_name = name;
 313         } else if (is_dev_null(second)) {
 314                 patch->is_new = 0;
 315                 patch->is_delete = 1;
 316                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 317                 patch->old_name = name;
 318         } else {
 319                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 320                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
 321                 patch->old_name = patch->new_name = name;
 322         }
 323         if (!name)
 324                 die("unable to find filename in patch at line %d", linenr);
 325 }
 326
 327 static int gitdiff_hdrend(const char *line, struct patch *patch)
 328 {
 329         return -1;
 330 }
 331
 332 /*
 333  * We're anal about diff header consistency, to make
 334  * sure that we don't end up having strange ambiguous
 335  * patches floating around.
 336  *
 337  * As a result, gitdiff_{old|new}name() will check
 338  * their names against any previous information, just
 339  * to make sure..
 340  */
 341 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
 342 {
 343         if (!orig_name && !isnull)
 344                 return find_name(line, NULL, 1, 0);
 345
 346         if (orig_name) {
 347                 int len;
 348                 const char *name;
 349                 char *another;
 350                 name = orig_name;
 351                 len = strlen(name);
 352                 if (isnull)
 353                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
 354                 another = find_name(line, NULL, 1, 0);
 355                 if (!another || memcmp(another, name, len))
 356                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
 357                 free(another);
 358                 return orig_name;
 359         }
 360         else {
 361                 /* expect "/dev/null" */
 362                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
 363                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
 364                 return NULL;
 365         }
 366 }
 367
 368 static int gitdiff_oldname(const char *line, struct patch *patch)
 369 {
 370         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
 371         return 0;
 372 }
 373
 374 static int gitdiff_newname(const char *line, struct patch *patch)
 375 {
 376         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
 377         return 0;
 378 }
 379
 380 static int gitdiff_oldmode(const char *line, struct patch *patch)
 381 {
 382         patch->old_mode = strtoul(line, NULL, 8);
 383         return 0;
 384 }
 385
 386 static int gitdiff_newmode(const char *line, struct patch *patch)
 387 {
 388         patch->new_mode = strtoul(line, NULL, 8);
 389         return 0;
 390 }
 391
 392 static int gitdiff_delete(const char *line, struct patch *patch)
 393 {
 394         patch->is_delete = 1;
 395         patch->old_name = patch->def_name;
 396         return gitdiff_oldmode(line, patch);
 397 }
 398
 399 static int gitdiff_newfile(const char *line, struct patch *patch)
 400 {
 401         patch->is_new = 1;
 402         patch->new_name = patch->def_name;
 403         return gitdiff_newmode(line, patch);
 404 }
 405
 406 static int gitdiff_copysrc(const char *line, struct patch *patch)
 407 {
 408         patch->is_copy = 1;
 409         patch->old_name = find_name(line, NULL, 0, 0);
 410         return 0;
 411 }
 412
 413 static int gitdiff_copydst(const char *line, struct patch *patch)
 414 {
 415         patch->is_copy = 1;
 416         patch->new_name = find_name(line, NULL, 0, 0);
 417         return 0;
 418 }
 419
 420 static int gitdiff_renamesrc(const char *line, struct patch *patch)
 421 {
 422         patch->is_rename = 1;
 423         patch->old_name = find_name(line, NULL, 0, 0);
 424         return 0;
 425 }
 426
 427 static int gitdiff_renamedst(const char *line, struct patch *patch)
 428 {
 429         patch->is_rename = 1;
 430         patch->new_name = find_name(line, NULL, 0, 0);
 431         return 0;
 432 }
 433
 434 static int gitdiff_similarity(const char *line, struct patch *patch)
 435 {
 436         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 437                 patch->score = 0;
 438         return 0;
 439 }
 440
 441 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
 442 {
 443         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 444                 patch->score = 0;
 445         return 0;
 446 }
 447
 448 static int gitdiff_index(const char *line, struct patch *patch)
 449 {
 450         /* index line is N hexadecimal, "..", N hexadecimal,
 451          * and optional space with octal mode.
 452          */
 453         const char *ptr, *eol;
 454         int len;
 455
 456         ptr = strchr(line, '.');
 457         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
 458                 return 0;
 459         len = ptr - line;
 460         memcpy(patch->old_sha1_prefix, line, len);
 461         patch->old_sha1_prefix[len] = 0;
 462
 463         line = ptr + 2;
 464         ptr = strchr(line, ' ');
 465         eol = strchr(line, '\n');
 466
 467         if (!ptr || eol < ptr)
 468                 ptr = eol;
 469         len = ptr - line;
 470
 471         if (40 < len)
 472                 return 0;
 473         memcpy(patch->new_sha1_prefix, line, len);
 474         patch->new_sha1_prefix[len] = 0;
 475         if (*ptr == ' ')
 476                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
 477         return 0;
 478 }
 479
 480 /*
 481  * This is normal for a diff that doesn't change anything: we'll fall through
 482  * into the next diff. Tell the parser to break out.
 483  */
 484 static int gitdiff_unrecognized(const char *line, struct patch *patch)
 485 {
 486         return -1;
 487 }
 488
 489 static const char *stop_at_slash(const char *line, int llen)
 490 {
 491         int i;
 492
 493         for (i = 0; i < llen; i++) {
 494                 int ch = line[i];
 495                 if (ch == '/')
 496                         return line + i;
 497         }
 498         return NULL;
 499 }
 500
 501 /* This is to extract the same name that appears on "diff --git"
 502  * line.  We do not find and return anything if it is a rename
 503  * patch, and it is OK because we will find the name elsewhere.
 504  * We need to reliably find name only when it is mode-change only,
 505  * creation or deletion of an empty file.  In any of these cases,
 506  * both sides are the same name under a/ and b/ respectively.
 507  */
 508 static char *git_header_name(char *line, int llen)
 509 {
 510         int len;
 511         const char *name;
 512         const char *second = NULL;
 513
 514         line += strlen("diff --git ");
 515         llen -= strlen("diff --git ");
 516
 517         if (*line == '"') {
 518                 const char *cp;
 519                 char *first = unquote_c_style(line, &second);
 520                 if (!first)
 521                         return NULL;
 522
 523                 /* advance to the first slash */
 524                 cp = stop_at_slash(first, strlen(first));
 525                 if (!cp || cp == first) {
 526                         /* we do not accept absolute paths */
 527                 free_first_and_fail:
 528                         free(first);
 529                         return NULL;
 530                 }
 531                 len = strlen(cp+1);
 532                 memmove(first, cp+1, len+1); /* including NUL */
 533
 534                 /* second points at one past closing dq of name.
 535                  * find the second name.
 536                  */
 537                 while ((second < line + llen) && isspace(*second))
 538                         second++;
 539
 540                 if (line + llen <= second)
 541                         goto free_first_and_fail;
 542                 if (*second == '"') {
 543                         char *sp = unquote_c_style(second, NULL);
 544                         if (!sp)
 545                                 goto free_first_and_fail;
 546                         cp = stop_at_slash(sp, strlen(sp));
 547                         if (!cp || cp == sp) {
 548                         free_both_and_fail:
 549                                 free(sp);
 550                                 goto free_first_and_fail;
 551                         }
 552                         /* They must match, otherwise ignore */
 553                         if (strcmp(cp+1, first))
 554                                 goto free_both_and_fail;
 555                         free(sp);
 556                         return first;
 557                 }
 558
 559                 /* unquoted second */
 560                 cp = stop_at_slash(second, line + llen - second);
 561                 if (!cp || cp == second)
 562                         goto free_first_and_fail;
 563                 cp++;
 564                 if (line + llen - cp != len + 1 ||
 565                     memcmp(first, cp, len))
 566                         goto free_first_and_fail;
 567                 return first;
 568         }
 569
 570         /* unquoted first name */
 571         name = stop_at_slash(line, llen);
 572         if (!name || name == line)
 573                 return NULL;
 574
 575         name++;
 576
 577         /* since the first name is unquoted, a dq if exists must be
 578          * the beginning of the second name.
 579          */
 580         for (second = name; second < line + llen; second++) {
 581                 if (*second == '"') {
 582                         const char *cp = second;
 583                         const char *np;
 584                         char *sp = unquote_c_style(second, NULL);
 585
 586                         if (!sp)
 587                                 return NULL;
 588                         np = stop_at_slash(sp, strlen(sp));
 589                         if (!np || np == sp) {
 590                         free_second_and_fail:
 591                                 free(sp);
 592                                 return NULL;
 593                         }
 594                         np++;
 595                         len = strlen(np);
 596                         if (len < cp - name &&
 597                             !strncmp(np, name, len) &&
 598                             isspace(name[len])) {
 599                                 /* Good */
 600                                 memmove(sp, np, len + 1);
 601                                 return sp;
 602                         }
 603                         goto free_second_and_fail;
 604                 }
 605         }
 606
 607         /*
 608          * Accept a name only if it shows up twice, exactly the same
 609          * form.
 610          */
 611         for (len = 0 ; ; len++) {
 612                 char c = name[len];
 613
 614                 switch (c) {
 615                 default:
 616                         continue;
 617                 case '\n':
 618                         return NULL;
 619                 case '\t': case ' ':
 620                         second = name+len;
 621                         for (;;) {
 622                                 char c = *second++;
 623                                 if (c == '\n')
 624                                         return NULL;
 625                                 if (c == '/')
 626                                         break;
 627                         }
 628                         if (second[len] == '\n' && !memcmp(name, second, len)) {
 629                                 char *ret = xmalloc(len + 1);
 630                                 memcpy(ret, name, len);
 631                                 ret[len] = 0;
 632                                 return ret;
 633                         }
 634                 }
 635         }
 636         return NULL;
 637 }
 638
 639 /* Verify that we recognize the lines following a git header */
 640 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
 641 {
 642         unsigned long offset;
 643
 644         /* A git diff has explicit new/delete information, so we don't guess */
 645         patch->is_new = 0;
 646         patch->is_delete = 0;
 647
 648         /*
 649          * Some things may not have the old name in the
 650          * rest of the headers anywhere (pure mode changes,
 651          * or removing or adding empty files), so we get
 652          * the default name from the header.
 653          */
 654         patch->def_name = git_header_name(line, len);
 655
 656         line += len;
 657         size -= len;
 658         linenr++;
 659         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
 660                 static const struct opentry {
 661                         const char *str;
 662                         int (*fn)(const char *, struct patch *);
 663                 } optable[] = {
 664                         { "@@ -", gitdiff_hdrend },
 665                         { "--- ", gitdiff_oldname },
 666                         { "+++ ", gitdiff_newname },
 667                         { "old mode ", gitdiff_oldmode },
 668                         { "new mode ", gitdiff_newmode },
 669                         { "deleted file mode ", gitdiff_delete },
 670                         { "new file mode ", gitdiff_newfile },
 671                         { "copy from ", gitdiff_copysrc },
 672                         { "copy to ", gitdiff_copydst },
 673                         { "rename old ", gitdiff_renamesrc },
 674                         { "rename new ", gitdiff_renamedst },
 675                         { "rename from ", gitdiff_renamesrc },
 676                         { "rename to ", gitdiff_renamedst },
 677                         { "similarity index ", gitdiff_similarity },
 678                         { "dissimilarity index ", gitdiff_dissimilarity },
 679                         { "index ", gitdiff_index },
 680                         { "", gitdiff_unrecognized },
 681                 };
 682                 int i;
 683
 684                 len = linelen(line, size);
 685                 if (!len || line[len-1] != '\n')
 686                         break;
 687                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
 688                         const struct opentry *p = optable + i;
 689                         int oplen = strlen(p->str);
 690                         if (len < oplen || memcmp(p->str, line, oplen))
 691                                 continue;
 692                         if (p->fn(line + oplen, patch) < 0)
 693                                 return offset;
 694                         break;
 695                 }
 696         }
 697
 698         return offset;
 699 }
 700
 701 static int parse_num(const char *line, unsigned long *p)
 702 {
 703         char *ptr;
 704
 705         if (!isdigit(*line))
 706                 return 0;
 707         *p = strtoul(line, &ptr, 10);
 708         return ptr - line;
 709 }
 710
 711 static int parse_range(const char *line, int len, int offset, const char *expect,
 712                         unsigned long *p1, unsigned long *p2)
 713 {
 714         int digits, ex;
 715
 716         if (offset < 0 || offset >= len)
 717                 return -1;
 718         line += offset;
 719         len -= offset;
 720
 721         digits = parse_num(line, p1);
 722         if (!digits)
 723                 return -1;
 724
 725         offset += digits;
 726         line += digits;
 727         len -= digits;
 728
 729         *p2 = 1;
 730         if (*line == ',') {
 731                 digits = parse_num(line+1, p2);
 732                 if (!digits)
 733                         return -1;
 734
 735                 offset += digits+1;
 736                 line += digits+1;
 737                 len -= digits+1;
 738         }
 739
 740         ex = strlen(expect);
 741         if (ex > len)
 742                 return -1;
 743         if (memcmp(line, expect, ex))
 744                 return -1;
 745
 746         return offset + ex;
 747 }
 748
 749 /*
 750  * Parse a unified diff fragment header of the
 751  * form "@@ -a,b +c,d @@"
 752  */
 753 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
 754 {
 755         int offset;
 756
 757         if (!len || line[len-1] != '\n')
 758                 return -1;
 759
 760         /* Figure out the number of lines in a fragment */
 761         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
 762         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 763
 764         return offset;
 765 }
 766
 767 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
 768 {
 769         unsigned long offset, len;
 770
 771         patch->is_rename = patch->is_copy = 0;
 772         patch->is_new = patch->is_delete = -1;
 773         patch->old_mode = patch->new_mode = 0;
 774         patch->old_name = patch->new_name = NULL;
 775         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
 776                 unsigned long nextlen;
 777
 778                 len = linelen(line, size);
 779                 if (!len)
 780                         break;
 781
 782                 /* Testing this early allows us to take a few shortcuts.. */
 783                 if (len < 6)
 784                         continue;
 785
 786                 /*
 787                  * Make sure we don't find any unconnected patch fragments.
 788                  * That's a sign that we didn't find a header, and that a
 789                  * patch has become corrupted/broken up.
 790                  */
 791                 if (!memcmp("@@ -", line, 4)) {
 792                         struct fragment dummy;
 793                         if (parse_fragment_header(line, len, &dummy) < 0)
 794                                 continue;
 795                         error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
 796                 }
 797
 798                 if (size < len + 6)
 799                         break;
 800
 801                 /*
 802                  * Git patch? It might not have a real patch, just a rename
 803                  * or mode change, so we handle that specially
 804                  */
 805                 if (!memcmp("diff --git ", line, 11)) {
 806                         int git_hdr_len = parse_git_header(line, len, size, patch);
 807                         if (git_hdr_len <= len)
 808                                 continue;
 809                         if (!patch->old_name && !patch->new_name) {
 810                                 if (!patch->def_name)
 811                                         die("git diff header lacks filename information (line %d)", linenr);
 812                                 patch->old_name = patch->new_name = patch->def_name;
 813                         }
 814                         *hdrsize = git_hdr_len;
 815                         return offset;
 816                 }
 817
 818                 /** --- followed by +++ ? */
 819                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
 820                         continue;
 821
 822                 /*
 823                  * We only accept unified patches, so we want it to
 824                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
 825                  * minimum
 826                  */
 827                 nextlen = linelen(line + len, size - len);
 828                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
 829                         continue;
 830
 831                 /* Ok, we'll consider it a patch */
 832                 parse_traditional_patch(line, line+len, patch);
 833                 *hdrsize = len + nextlen;
 834                 linenr += 2;
 835                 return offset;
 836         }
 837         return -1;
 838 }
 839
 840 /*
 841  * Parse a unified diff. Note that this really needs
 842  * to parse each fragment separately, since the only
 843  * way to know the difference between a "---" that is
 844  * part of a patch, and a "---" that starts the next
 845  * patch is to look at the line counts..
 846  */
 847 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
 848 {
 849         int added, deleted;
 850         int len = linelen(line, size), offset;
 851         unsigned long oldlines, newlines;
 852         unsigned long leading, trailing;
 853
 854         offset = parse_fragment_header(line, len, fragment);
 855         if (offset < 0)
 856                 return -1;
 857         oldlines = fragment->oldlines;
 858         newlines = fragment->newlines;
 859         leading = 0;
 860         trailing = 0;
 861
 862         if (patch->is_new < 0) {
 863                 patch->is_new =  !oldlines;
 864                 if (!oldlines)
 865                         patch->old_name = NULL;
 866         }
 867         if (patch->is_delete < 0) {
 868                 patch->is_delete = !newlines;
 869                 if (!newlines)
 870                         patch->new_name = NULL;
 871         }
 872
 873         if (patch->is_new && oldlines)
 874                 return error("new file depends on old contents");
 875         if (patch->is_delete != !newlines) {
 876                 if (newlines)
 877                         return error("deleted file still has contents");
 878                 fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
 879         }
 880
 881         /* Parse the thing.. */
 882         line += len;
 883         size -= len;
 884         linenr++;
 885         added = deleted = 0;
 886         for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
 887                 if (!oldlines && !newlines)
 888                         break;
 889                 len = linelen(line, size);
 890                 if (!len || line[len-1] != '\n')
 891                         return -1;
 892                 switch (*line) {
 893                 default:
 894                         return -1;
 895                 case ' ':
 896                         oldlines--;
 897                         newlines--;
 898                         if (!deleted && !added)
 899                                 leading++;
 900                         trailing++;
 901                         break;
 902                 case '-':
 903                         deleted++;
 904                         oldlines--;
 905                         trailing = 0;
 906                         break;
 907                 case '+':
 908                         /*
 909                          * We know len is at least two, since we have a '+' and
 910                          * we checked that the last character was a '\n' above.
 911                          * That is, an addition of an empty line would check
 912                          * the '+' here.  Sneaky...
 913                          */
 914                         if ((new_whitespace != nowarn_whitespace) &&
 915                             isspace(line[len-2])) {
 916                                 whitespace_error++;
 917                                 if (squelch_whitespace_errors &&
 918                                     squelch_whitespace_errors <
 919                                     whitespace_error)
 920                                         ;
 921                                 else {
 922                                         fprintf(stderr, "Adds trailing whitespace.\n%s:%d:%.*s\n",
 923                                                 patch_input_file,
 924                                                 linenr, len-2, line+1);
 925                                 }
 926                         }
 927                         added++;
 928                         newlines--;
 929                         trailing = 0;
 930                         break;
 931
 932                 /* We allow "\ No newline at end of file". Depending
 933                  * on locale settings when the patch was produced we
 934                  * don't know what this line looks like. The only
 935                  * thing we do know is that it begins with "\ ".
 936                  * Checking for 12 is just for sanity check -- any
 937                  * l10n of "\ No newline..." is at least that long.
 938                  */
 939                 case '\\':
 940                         if (len < 12 || memcmp(line, "\\ ", 2))
 941                                 return -1;
 942                         break;
 943                 }
 944         }
 945         if (oldlines || newlines)
 946                 return -1;
 947         fragment->leading = leading;
 948         fragment->trailing = trailing;
 949
 950         /* If a fragment ends with an incomplete line, we failed to include
 951          * it in the above loop because we hit oldlines == newlines == 0
 952          * before seeing it.
 953          */
 954         if (12 < size && !memcmp(line, "\\ ", 2))
 955                 offset += linelen(line, size);
 956
 957         patch->lines_added += added;
 958         patch->lines_deleted += deleted;
 959         return offset;
 960 }
 961
 962 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
 963 {
 964         unsigned long offset = 0;
 965         struct fragment **fragp = &patch->fragments;
 966
 967         while (size > 4 && !memcmp(line, "@@ -", 4)) {
 968                 struct fragment *fragment;
 969                 int len;
 970
 971                 fragment = xcalloc(1, sizeof(*fragment));
 972                 len = parse_fragment(line, size, patch, fragment);
 973                 if (len <= 0)
 974                         die("corrupt patch at line %d", linenr);
 975
 976                 fragment->patch = line;
 977                 fragment->size = len;
 978
 979                 *fragp = fragment;
 980                 fragp = &fragment->next;
 981
 982                 offset += len;
 983                 line += len;
 984                 size -= len;
 985         }
 986         return offset;
 987 }
 988
 989 static inline int metadata_changes(struct patch *patch)
 990 {
 991         return  patch->is_rename > 0 ||
 992                 patch->is_copy > 0 ||
 993                 patch->is_new > 0 ||
 994                 patch->is_delete ||
 995                 (patch->old_mode && patch->new_mode &&
 996                  patch->old_mode != patch->new_mode);
 997 }
 998
 999 static char *inflate_it(const void *data, unsigned long size,
1000                         unsigned long inflated_size)
1001 {
1002         z_stream stream;
1003         void *out;
1004         int st;
1005
1006         memset(&stream, 0, sizeof(stream));
1007
1008         stream.next_in = (unsigned char *)data;
1009         stream.avail_in = size;
1010         stream.next_out = out = xmalloc(inflated_size);
1011         stream.avail_out = inflated_size;
1012         inflateInit(&stream);
1013         st = inflate(&stream, Z_FINISH);
1014         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1015                 free(out);
1016                 return NULL;
1017         }
1018         return out;
1019 }
1020
1021 static struct fragment *parse_binary_hunk(char **buf_p,
1022                                           unsigned long *sz_p,
1023                                           int *status_p,
1024                                           int *used_p)
1025 {
1026         /* Expect a line that begins with binary patch method ("literal"
1027          * or "delta"), followed by the length of data before deflating.
1028          * a sequence of 'length-byte' followed by base-85 encoded data
1029          * should follow, terminated by a newline.
1030          *
1031          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1032          * and we would limit the patch line to 66 characters,
1033          * so one line can fit up to 13 groups that would decode
1034          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1035          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1036          */
1037         int llen, used;
1038         unsigned long size = *sz_p;
1039         char *buffer = *buf_p;
1040         int patch_method;
1041         unsigned long origlen;
1042         char *data = NULL;
1043         int hunk_size = 0;
1044         struct fragment *frag;
1045
1046         llen = linelen(buffer, size);
1047         used = llen;
1048
1049         *status_p = 0;
1050
1051         if (!strncmp(buffer, "delta ", 6)) {
1052                 patch_method = BINARY_DELTA_DEFLATED;
1053                 origlen = strtoul(buffer + 6, NULL, 10);
1054         }
1055         else if (!strncmp(buffer, "literal ", 8)) {
1056                 patch_method = BINARY_LITERAL_DEFLATED;
1057                 origlen = strtoul(buffer + 8, NULL, 10);
1058         }
1059         else
1060                 return NULL;
1061
1062         linenr++;
1063         buffer += llen;
1064         while (1) {
1065                 int byte_length, max_byte_length, newsize;
1066                 llen = linelen(buffer, size);
1067                 used += llen;
1068                 linenr++;
1069                 if (llen == 1) {
1070                         /* consume the blank line */
1071                         buffer++;
1072                         size--;
1073                         break;
1074                 }
1075                 /* Minimum line is "A00000\n" which is 7-byte long,
1076                  * and the line length must be multiple of 5 plus 2.
1077                  */
1078                 if ((llen < 7) || (llen-2) % 5)
1079                         goto corrupt;
1080                 max_byte_length = (llen - 2) / 5 * 4;
1081                 byte_length = *buffer;
1082                 if ('A' <= byte_length && byte_length <= 'Z')
1083                         byte_length = byte_length - 'A' + 1;
1084                 else if ('a' <= byte_length && byte_length <= 'z')
1085                         byte_length = byte_length - 'a' + 27;
1086                 else
1087                         goto corrupt;
1088                 /* if the input length was not multiple of 4, we would
1089                  * have filler at the end but the filler should never
1090                  * exceed 3 bytes
1091                  */
1092                 if (max_byte_length < byte_length ||
1093                     byte_length <= max_byte_length - 4)
1094                         goto corrupt;
1095                 newsize = hunk_size + byte_length;
1096                 data = xrealloc(data, newsize);
1097                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1098                         goto corrupt;
1099                 hunk_size = newsize;
1100                 buffer += llen;
1101                 size -= llen;
1102         }
1103
1104         frag = xcalloc(1, sizeof(*frag));
1105         frag->patch = inflate_it(data, hunk_size, origlen);
1106         if (!frag->patch)
1107                 goto corrupt;
1108         free(data);
1109         frag->size = origlen;
1110         *buf_p = buffer;
1111         *sz_p = size;
1112         *used_p = used;
1113         frag->binary_patch_method = patch_method;
1114         return frag;
1115
1116  corrupt:
1117         if (data)
1118                 free(data);
1119         *status_p = -1;
1120         error("corrupt binary patch at line %d: %.*s",
1121               linenr-1, llen-1, buffer);
1122         return NULL;
1123 }
1124
1125 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1126 {
1127         /* We have read "GIT binary patch\n"; what follows is a line
1128          * that says the patch method (currently, either "literal" or
1129          * "delta") and the length of data before deflating; a
1130          * sequence of 'length-byte' followed by base-85 encoded data
1131          * follows.
1132          *
1133          * When a binary patch is reversible, there is another binary
1134          * hunk in the same format, starting with patch method (either
1135          * "literal" or "delta") with the length of data, and a sequence
1136          * of length-byte + base-85 encoded data, terminated with another
1137          * empty line.  This data, when applied to the postimage, produces
1138          * the preimage.
1139          */
1140         struct fragment *forward;
1141         struct fragment *reverse;
1142         int status;
1143         int used, used_1;
1144
1145         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1146         if (!forward && !status)
1147                 /* there has to be one hunk (forward hunk) */
1148                 return error("unrecognized binary patch at line %d", linenr-1);
1149         if (status)
1150                 /* otherwise we already gave an error message */
1151                 return status;
1152
1153         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1154         if (reverse)
1155                 used += used_1;
1156         else if (status) {
1157                 /* not having reverse hunk is not an error, but having
1158                  * a corrupt reverse hunk is.
1159                  */
1160                 free((void*) forward->patch);
1161                 free(forward);
1162                 return status;
1163         }
1164         forward->next = reverse;
1165         patch->fragments = forward;
1166         patch->is_binary = 1;
1167         return used;
1168 }
1169
1170 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1171 {
1172         int hdrsize, patchsize;
1173         int offset = find_header(buffer, size, &hdrsize, patch);
1174
1175         if (offset < 0)
1176                 return offset;
1177
1178         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
1179
1180         if (!patchsize) {
1181                 static const char *binhdr[] = {
1182                         "Binary files ",
1183                         "Files ",
1184                         NULL,
1185                 };
1186                 static const char git_binary[] = "GIT binary patch\n";
1187                 int i;
1188                 int hd = hdrsize + offset;
1189                 unsigned long llen = linelen(buffer + hd, size - hd);
1190
1191                 if (llen == sizeof(git_binary) - 1 &&
1192                     !memcmp(git_binary, buffer + hd, llen)) {
1193                         int used;
1194                         linenr++;
1195                         used = parse_binary(buffer + hd + llen,
1196                                             size - hd - llen, patch);
1197                         if (used)
1198                                 patchsize = used + llen;
1199                         else
1200                                 patchsize = 0;
1201                 }
1202                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1203                         for (i = 0; binhdr[i]; i++) {
1204                                 int len = strlen(binhdr[i]);
1205                                 if (len < size - hd &&
1206                                     !memcmp(binhdr[i], buffer + hd, len)) {
1207                                         linenr++;
1208                                         patch->is_binary = 1;
1209                                         patchsize = llen;
1210                                         break;
1211                                 }
1212                         }
1213                 }
1214
1215                 /* Empty patch cannot be applied if:
1216                  * - it is a binary patch and we do not do binary_replace, or
1217                  * - text patch without metadata change
1218                  */
1219                 if ((apply || check) &&
1220                     (patch->is_binary
1221                      ? !allow_binary_replacement
1222                      : !metadata_changes(patch)))
1223                         die("patch with only garbage at line %d", linenr);
1224         }
1225
1226         return offset + hdrsize + patchsize;
1227 }
1228
1229 #define swap(a,b) myswap((a),(b),sizeof(a))
1230
1231 #define myswap(a, b, size) do {         \
1232         unsigned char mytmp[size];      \
1233         memcpy(mytmp, &a, size);                \
1234         memcpy(&a, &b, size);           \
1235         memcpy(&b, mytmp, size);                \
1236 } while (0)
1237
1238 static void reverse_patches(struct patch *p)
1239 {
1240         for (; p; p = p->next) {
1241                 struct fragment *frag = p->fragments;
1242
1243                 swap(p->new_name, p->old_name);
1244                 swap(p->new_mode, p->old_mode);
1245                 swap(p->is_new, p->is_delete);
1246                 swap(p->lines_added, p->lines_deleted);
1247                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1248
1249                 for (; frag; frag = frag->next) {
1250                         swap(frag->newpos, frag->oldpos);
1251                         swap(frag->newlines, frag->oldlines);
1252                 }
1253         }
1254 }
1255
1256 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1257 static const char minuses[]= "----------------------------------------------------------------------";
1258
1259 static void show_stats(struct patch *patch)
1260 {
1261         const char *prefix = "";
1262         char *name = patch->new_name;
1263         char *qname = NULL;
1264         int len, max, add, del, total;
1265
1266         if (!name)
1267                 name = patch->old_name;
1268
1269         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
1270                 qname = xmalloc(len + 1);
1271                 quote_c_style(name, qname, NULL, 0);
1272                 name = qname;
1273         }
1274
1275         /*
1276          * "scale" the filename
1277          */
1278         len = strlen(name);
1279         max = max_len;
1280         if (max > 50)
1281                 max = 50;
1282         if (len > max) {
1283                 char *slash;
1284                 prefix = "...";
1285                 max -= 3;
1286                 name += len - max;
1287                 slash = strchr(name, '/');
1288                 if (slash)
1289                         name = slash;
1290         }
1291         len = max;
1292
1293         /*
1294          * scale the add/delete
1295          */
1296         max = max_change;
1297         if (max + len > 70)
1298                 max = 70 - len;
1299
1300         add = patch->lines_added;
1301         del = patch->lines_deleted;
1302         total = add + del;
1303
1304         if (max_change > 0) {
1305                 total = (total * max + max_change / 2) / max_change;
1306                 add = (add * max + max_change / 2) / max_change;
1307                 del = total - add;
1308         }
1309         if (patch->is_binary)
1310                 printf(" %s%-*s |  Bin\n", prefix, len, name);
1311         else
1312                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1313                        len, name, patch->lines_added + patch->lines_deleted,
1314                        add, pluses, del, minuses);
1315         if (qname)
1316                 free(qname);
1317 }
1318
1319 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
1320 {
1321         int fd;
1322         unsigned long got;
1323
1324         switch (st->st_mode & S_IFMT) {
1325         case S_IFLNK:
1326                 return readlink(path, buf, size);
1327         case S_IFREG:
1328                 fd = open(path, O_RDONLY);
1329                 if (fd < 0)
1330                         return error("unable to open %s", path);
1331                 got = 0;
1332                 for (;;) {
1333                         int ret = xread(fd, (char *) buf + got, size - got);
1334                         if (ret <= 0)
1335                                 break;
1336                         got += ret;
1337                 }
1338                 close(fd);
1339                 return got;
1340
1341         default:
1342                 return -1;
1343         }
1344 }
1345
1346 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
1347 {
1348         int i;
1349         unsigned long start, backwards, forwards;
1350
1351         if (fragsize > size)
1352                 return -1;
1353
1354         start = 0;
1355         if (line > 1) {
1356                 unsigned long offset = 0;
1357                 i = line-1;
1358                 while (offset + fragsize <= size) {
1359                         if (buf[offset++] == '\n') {
1360                                 start = offset;
1361                                 if (!--i)
1362                                         break;
1363                         }
1364                 }
1365         }
1366
1367         /* Exact line number? */
1368         if (!memcmp(buf + start, fragment, fragsize))
1369                 return start;
1370
1371         /*
1372          * There's probably some smart way to do this, but I'll leave
1373          * that to the smart and beautiful people. I'm simple and stupid.
1374          */
1375         backwards = start;
1376         forwards = start;
1377         for (i = 0; ; i++) {
1378                 unsigned long try;
1379                 int n;
1380
1381                 /* "backward" */
1382                 if (i & 1) {
1383                         if (!backwards) {
1384                                 if (forwards + fragsize > size)
1385                                         break;
1386                                 continue;
1387                         }
1388                         do {
1389                                 --backwards;
1390                         } while (backwards && buf[backwards-1] != '\n');
1391                         try = backwards;
1392                 } else {
1393                         while (forwards + fragsize <= size) {
1394                                 if (buf[forwards++] == '\n')
1395                                         break;
1396                         }
1397                         try = forwards;
1398                 }
1399
1400                 if (try + fragsize > size)
1401                         continue;
1402                 if (memcmp(buf + try, fragment, fragsize))
1403                         continue;
1404                 n = (i >> 1)+1;
1405                 if (i & 1)
1406                         n = -n;
1407                 *lines = n;
1408                 return try;
1409         }
1410
1411         /*
1412          * We should start searching forward and backward.
1413          */
1414         return -1;
1415 }
1416
1417 static void remove_first_line(const char **rbuf, int *rsize)
1418 {
1419         const char *buf = *rbuf;
1420         int size = *rsize;
1421         unsigned long offset;
1422         offset = 0;
1423         while (offset <= size) {
1424                 if (buf[offset++] == '\n')
1425                         break;
1426         }
1427         *rsize = size - offset;
1428         *rbuf = buf + offset;
1429 }
1430
1431 static void remove_last_line(const char **rbuf, int *rsize)
1432 {
1433         const char *buf = *rbuf;
1434         int size = *rsize;
1435         unsigned long offset;
1436         offset = size - 1;
1437         while (offset > 0) {
1438                 if (buf[--offset] == '\n')
1439                         break;
1440         }
1441         *rsize = offset + 1;
1442 }
1443
1444 struct buffer_desc {
1445         char *buffer;
1446         unsigned long size;
1447         unsigned long alloc;
1448 };
1449
1450 static int apply_line(char *output, const char *patch, int plen)
1451 {
1452         /* plen is number of bytes to be copied from patch,
1453          * starting at patch+1 (patch[0] is '+').  Typically
1454          * patch[plen] is '\n'.
1455          */
1456         int add_nl_to_tail = 0;
1457         if ((new_whitespace == strip_whitespace) &&
1458             1 < plen && isspace(patch[plen-1])) {
1459                 if (patch[plen] == '\n')
1460                         add_nl_to_tail = 1;
1461                 plen--;
1462                 while (0 < plen && isspace(patch[plen]))
1463                         plen--;
1464                 applied_after_stripping++;
1465         }
1466         memcpy(output, patch + 1, plen);
1467         if (add_nl_to_tail)
1468                 output[plen++] = '\n';
1469         return plen;
1470 }
1471
1472 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag, int inaccurate_eof)
1473 {
1474         int match_beginning, match_end;
1475         char *buf = desc->buffer;
1476         const char *patch = frag->patch;
1477         int offset, size = frag->size;
1478         char *old = xmalloc(size);
1479         char *new = xmalloc(size);
1480         const char *oldlines, *newlines;
1481         int oldsize = 0, newsize = 0;
1482         unsigned long leading, trailing;
1483         int pos, lines;
1484
1485         while (size > 0) {
1486                 char first;
1487                 int len = linelen(patch, size);
1488                 int plen;
1489
1490                 if (!len)
1491                         break;
1492
1493                 /*
1494                  * "plen" is how much of the line we should use for
1495                  * the actual patch data. Normally we just remove the
1496                  * first character on the line, but if the line is
1497                  * followed by "\ No newline", then we also remove the
1498                  * last one (which is the newline, of course).
1499                  */
1500                 plen = len-1;
1501                 if (len < size && patch[len] == '\\')
1502                         plen--;
1503                 first = *patch;
1504                 if (apply_in_reverse) {
1505                         if (first == '-')
1506                                 first = '+';
1507                         else if (first == '+')
1508                                 first = '-';
1509                 }
1510                 switch (first) {
1511                 case ' ':
1512                 case '-':
1513                         memcpy(old + oldsize, patch + 1, plen);
1514                         oldsize += plen;
1515                         if (first == '-')
1516                                 break;
1517                 /* Fall-through for ' ' */
1518                 case '+':
1519                         if (first != '+' || !no_add)
1520                                 newsize += apply_line(new + newsize, patch,
1521                                                       plen);
1522                         break;
1523                 case '@': case '\\':
1524                         /* Ignore it, we already handled it */
1525                         break;
1526                 default:
1527                         return -1;
1528                 }
1529                 patch += len;
1530                 size -= len;
1531         }
1532
1533         if (inaccurate_eof && oldsize > 0 && old[oldsize - 1] == '\n' &&
1534                         newsize > 0 && new[newsize - 1] == '\n') {
1535                 oldsize--;
1536                 newsize--;
1537         }
1538
1539         oldlines = old;
1540         newlines = new;
1541         leading = frag->leading;
1542         trailing = frag->trailing;
1543
1544         /*
1545          * If we don't have any leading/trailing data in the patch,
1546          * we want it to match at the beginning/end of the file.
1547          */
1548         match_beginning = !leading && (frag->oldpos == 1);
1549         match_end = !trailing;
1550
1551         lines = 0;
1552         pos = frag->newpos;
1553         for (;;) {
1554                 offset = find_offset(buf, desc->size,
1555                                      oldlines, oldsize, pos, &lines);
1556                 if (match_end && offset + oldsize != desc->size)
1557                         offset = -1;
1558                 if (match_beginning && offset)
1559                         offset = -1;
1560                 if (offset >= 0) {
1561                         int diff = newsize - oldsize;
1562                         unsigned long size = desc->size + diff;
1563                         unsigned long alloc = desc->alloc;
1564
1565                         /* Warn if it was necessary to reduce the number
1566                          * of context lines.
1567                          */
1568                         if ((leading != frag->leading) ||
1569                             (trailing != frag->trailing))
1570                                 fprintf(stderr, "Context reduced to (%ld/%ld)"
1571                                         " to apply fragment at %d\n",
1572                                         leading, trailing, pos + lines);
1573
1574                         if (size > alloc) {
1575                                 alloc = size + 8192;
1576                                 desc->alloc = alloc;
1577                                 buf = xrealloc(buf, alloc);
1578                                 desc->buffer = buf;
1579                         }
1580                         desc->size = size;
1581                         memmove(buf + offset + newsize,
1582                                 buf + offset + oldsize,
1583                                 size - offset - newsize);
1584                         memcpy(buf + offset, newlines, newsize);
1585                         offset = 0;
1586
1587                         break;
1588                 }
1589
1590                 /* Am I at my context limits? */
1591                 if ((leading <= p_context) && (trailing <= p_context))
1592                         break;
1593                 if (match_beginning || match_end) {
1594                         match_beginning = match_end = 0;
1595                         continue;
1596                 }
1597                 /* Reduce the number of context lines
1598                  * Reduce both leading and trailing if they are equal
1599                  * otherwise just reduce the larger context.
1600                  */
1601                 if (leading >= trailing) {
1602                         remove_first_line(&oldlines, &oldsize);
1603                         remove_first_line(&newlines, &newsize);
1604                         pos--;
1605                         leading--;
1606                 }
1607                 if (trailing > leading) {
1608                         remove_last_line(&oldlines, &oldsize);
1609                         remove_last_line(&newlines, &newsize);
1610                         trailing--;
1611                 }
1612         }
1613
1614         free(old);
1615         free(new);
1616         return offset;
1617 }
1618
1619 static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch)
1620 {
1621         unsigned long dst_size;
1622         struct fragment *fragment = patch->fragments;
1623         void *data;
1624         void *result;
1625
1626         /* Binary patch is irreversible without the optional second hunk */
1627         if (apply_in_reverse) {
1628                 if (!fragment->next)
1629                         return error("cannot reverse-apply a binary patch "
1630                                      "without the reverse hunk to '%s'",
1631                                      patch->new_name
1632                                      ? patch->new_name : patch->old_name);
1633                 fragment = fragment->next;
1634         }
1635         data = (void*) fragment->patch;
1636         switch (fragment->binary_patch_method) {
1637         case BINARY_DELTA_DEFLATED:
1638                 result = patch_delta(desc->buffer, desc->size,
1639                                      data,
1640                                      fragment->size,
1641                                      &dst_size);
1642                 free(desc->buffer);
1643                 desc->buffer = result;
1644                 break;
1645         case BINARY_LITERAL_DEFLATED:
1646                 free(desc->buffer);
1647                 desc->buffer = data;
1648                 dst_size = fragment->size;
1649                 break;
1650         }
1651         if (!desc->buffer)
1652                 return -1;
1653         desc->size = desc->alloc = dst_size;
1654         return 0;
1655 }
1656
1657 static int apply_binary(struct buffer_desc *desc, struct patch *patch)
1658 {
1659         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1660         unsigned char sha1[20];
1661         unsigned char hdr[50];
1662         int hdrlen;
1663
1664         if (!allow_binary_replacement)
1665                 return error("cannot apply binary patch to '%s' "
1666                              "without --allow-binary-replacement",
1667                              name);
1668
1669         /* For safety, we require patch index line to contain
1670          * full 40-byte textual SHA1 for old and new, at least for now.
1671          */
1672         if (strlen(patch->old_sha1_prefix) != 40 ||
1673             strlen(patch->new_sha1_prefix) != 40 ||
1674             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1675             get_sha1_hex(patch->new_sha1_prefix, sha1))
1676                 return error("cannot apply binary patch to '%s' "
1677                              "without full index line", name);
1678
1679         if (patch->old_name) {
1680                 /* See if the old one matches what the patch
1681                  * applies to.
1682                  */
1683                 write_sha1_file_prepare(desc->buffer, desc->size,
1684                                         blob_type, sha1, hdr, &hdrlen);
1685                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1686                         return error("the patch applies to '%s' (%s), "
1687                                      "which does not match the "
1688                                      "current contents.",
1689                                      name, sha1_to_hex(sha1));
1690         }
1691         else {
1692                 /* Otherwise, the old one must be empty. */
1693                 if (desc->size)
1694                         return error("the patch applies to an empty "
1695                                      "'%s' but it is not empty", name);
1696         }
1697
1698         get_sha1_hex(patch->new_sha1_prefix, sha1);
1699         if (is_null_sha1(sha1)) {
1700                 free(desc->buffer);
1701                 desc->alloc = desc->size = 0;
1702                 desc->buffer = NULL;
1703                 return 0; /* deletion patch */
1704         }
1705
1706         if (has_sha1_file(sha1)) {
1707                 /* We already have the postimage */
1708                 char type[10];
1709                 unsigned long size;
1710
1711                 free(desc->buffer);
1712                 desc->buffer = read_sha1_file(sha1, type, &size);
1713                 if (!desc->buffer)
1714                         return error("the necessary postimage %s for "
1715                                      "'%s' cannot be read",
1716                                      patch->new_sha1_prefix, name);
1717                 desc->alloc = desc->size = size;
1718         }
1719         else {
1720                 /* We have verified desc matches the preimage;
1721                  * apply the patch data to it, which is stored
1722                  * in the patch->fragments->{patch,size}.
1723                  */
1724                 if (apply_binary_fragment(desc, patch))
1725                         return error("binary patch does not apply to '%s'",
1726                                      name);
1727
1728                 /* verify that the result matches */
1729                 write_sha1_file_prepare(desc->buffer, desc->size, blob_type,
1730                                         sha1, hdr, &hdrlen);
1731                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
1732                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)", name, patch->new_sha1_prefix, sha1_to_hex(sha1));
1733         }
1734
1735         return 0;
1736 }
1737
1738 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1739 {
1740         struct fragment *frag = patch->fragments;
1741         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1742
1743         if (patch->is_binary)
1744                 return apply_binary(desc, patch);
1745
1746         while (frag) {
1747                 if (apply_one_fragment(desc, frag, patch->inaccurate_eof)) {
1748                         error("patch failed: %s:%ld", name, frag->oldpos);
1749                         if (!apply_with_reject)
1750                                 return -1;
1751                         frag->rejected = 1;
1752                 }
1753                 frag = frag->next;
1754         }
1755         return 0;
1756 }
1757
1758 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
1759 {
1760         char *buf;
1761         unsigned long size, alloc;
1762         struct buffer_desc desc;
1763
1764         size = 0;
1765         alloc = 0;
1766         buf = NULL;
1767         if (cached) {
1768                 if (ce) {
1769                         char type[20];
1770                         buf = read_sha1_file(ce->sha1, type, &size);
1771                         if (!buf)
1772                                 return error("read of %s failed",
1773                                              patch->old_name);
1774                         alloc = size;
1775                 }
1776         }
1777         else if (patch->old_name) {
1778                 size = st->st_size;
1779                 alloc = size + 8192;
1780                 buf = xmalloc(alloc);
1781                 if (read_old_data(st, patch->old_name, buf, alloc) != size)
1782                         return error("read of %s failed", patch->old_name);
1783         }
1784
1785         desc.size = size;
1786         desc.alloc = alloc;
1787         desc.buffer = buf;
1788
1789         if (apply_fragments(&desc, patch) < 0)
1790                 return -1; /* note with --reject this succeeds. */
1791
1792         /* NUL terminate the result */
1793         if (desc.alloc <= desc.size)
1794                 desc.buffer = xrealloc(desc.buffer, desc.size + 1);
1795         desc.buffer[desc.size] = 0;
1796
1797         patch->result = desc.buffer;
1798         patch->resultsize = desc.size;
1799
1800         if (patch->is_delete && patch->resultsize)
1801                 return error("removal patch leaves file contents");
1802
1803         return 0;
1804 }
1805
1806 static int check_patch(struct patch *patch, struct patch *prev_patch)
1807 {
1808         struct stat st;
1809         const char *old_name = patch->old_name;
1810         const char *new_name = patch->new_name;
1811         const char *name = old_name ? old_name : new_name;
1812         struct cache_entry *ce = NULL;
1813         int ok_if_exists;
1814
1815         patch->rejected = 1; /* we will drop this after we succeed */
1816         if (old_name) {
1817                 int changed = 0;
1818                 int stat_ret = 0;
1819                 unsigned st_mode = 0;
1820
1821                 if (!cached)
1822                         stat_ret = lstat(old_name, &st);
1823                 if (check_index) {
1824                         int pos = cache_name_pos(old_name, strlen(old_name));
1825                         if (pos < 0)
1826                                 return error("%s: does not exist in index",
1827                                              old_name);
1828                         ce = active_cache[pos];
1829                         if (stat_ret < 0) {
1830                                 struct checkout costate;
1831                                 if (errno != ENOENT)
1832                                         return error("%s: %s", old_name,
1833                                                      strerror(errno));
1834                                 /* checkout */
1835                                 costate.base_dir = "";
1836                                 costate.base_dir_len = 0;
1837                                 costate.force = 0;
1838                                 costate.quiet = 0;
1839                                 costate.not_new = 0;
1840                                 costate.refresh_cache = 1;
1841                                 if (checkout_entry(ce,
1842                                                    &costate,
1843                                                    NULL) ||
1844                                     lstat(old_name, &st))
1845                                         return -1;
1846                         }
1847                         if (!cached)
1848                                 changed = ce_match_stat(ce, &st, 1);
1849                         if (changed)
1850                                 return error("%s: does not match index",
1851                                              old_name);
1852                         if (cached)
1853                                 st_mode = ntohl(ce->ce_mode);
1854                 }
1855                 else if (stat_ret < 0)
1856                         return error("%s: %s", old_name, strerror(errno));
1857
1858                 if (!cached)
1859                         st_mode = ntohl(create_ce_mode(st.st_mode));
1860
1861                 if (patch->is_new < 0)
1862                         patch->is_new = 0;
1863                 if (!patch->old_mode)
1864                         patch->old_mode = st_mode;
1865                 if ((st_mode ^ patch->old_mode) & S_IFMT)
1866                         return error("%s: wrong type", old_name);
1867                 if (st_mode != patch->old_mode)
1868                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
1869                                 old_name, st_mode, patch->old_mode);
1870         }
1871
1872         if (new_name && prev_patch && prev_patch->is_delete &&
1873             !strcmp(prev_patch->old_name, new_name))
1874                 /* A type-change diff is always split into a patch to
1875                  * delete old, immediately followed by a patch to
1876                  * create new (see diff.c::run_diff()); in such a case
1877                  * it is Ok that the entry to be deleted by the
1878                  * previous patch is still in the working tree and in
1879                  * the index.
1880                  */
1881                 ok_if_exists = 1;
1882         else
1883                 ok_if_exists = 0;
1884
1885         if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
1886                 if (check_index &&
1887                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
1888                     !ok_if_exists)
1889                         return error("%s: already exists in index", new_name);
1890                 if (!cached) {
1891                         struct stat nst;
1892                         if (!lstat(new_name, &nst)) {
1893                                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
1894                                         ; /* ok */
1895                                 else
1896                                         return error("%s: already exists in working directory", new_name);
1897                         }
1898                         else if ((errno != ENOENT) && (errno != ENOTDIR))
1899                                 return error("%s: %s", new_name, strerror(errno));
1900                 }
1901                 if (!patch->new_mode) {
1902                         if (patch->is_new)
1903                                 patch->new_mode = S_IFREG | 0644;
1904                         else
1905                                 patch->new_mode = patch->old_mode;
1906                 }
1907         }
1908
1909         if (new_name && old_name) {
1910                 int same = !strcmp(old_name, new_name);
1911                 if (!patch->new_mode)
1912                         patch->new_mode = patch->old_mode;
1913                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1914                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1915                                 patch->new_mode, new_name, patch->old_mode,
1916                                 same ? "" : " of ", same ? "" : old_name);
1917         }
1918
1919         if (apply_data(patch, &st, ce) < 0)
1920                 return error("%s: patch does not apply", name);
1921         patch->rejected = 0;
1922         return 0;
1923 }
1924
1925 static int check_patch_list(struct patch *patch)
1926 {
1927         struct patch *prev_patch = NULL;
1928         int error = 0;
1929
1930         for (prev_patch = NULL; patch ; patch = patch->next) {
1931                 error |= check_patch(patch, prev_patch);
1932                 prev_patch = patch;
1933         }
1934         return error;
1935 }
1936
1937 static void show_index_list(struct patch *list)
1938 {
1939         struct patch *patch;
1940
1941         /* Once we start supporting the reverse patch, it may be
1942          * worth showing the new sha1 prefix, but until then...
1943          */
1944         for (patch = list; patch; patch = patch->next) {
1945                 const unsigned char *sha1_ptr;
1946                 unsigned char sha1[20];
1947                 const char *name;
1948
1949                 name = patch->old_name ? patch->old_name : patch->new_name;
1950                 if (patch->is_new)
1951                         sha1_ptr = null_sha1;
1952                 else if (get_sha1(patch->old_sha1_prefix, sha1))
1953                         die("sha1 information is lacking or useless (%s).",
1954                             name);
1955                 else
1956                         sha1_ptr = sha1;
1957
1958                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
1959                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1960                         quote_c_style(name, NULL, stdout, 0);
1961                 else
1962                         fputs(name, stdout);
1963                 putchar(line_termination);
1964         }
1965 }
1966
1967 static void stat_patch_list(struct patch *patch)
1968 {
1969         int files, adds, dels;
1970
1971         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
1972                 files++;
1973                 adds += patch->lines_added;
1974                 dels += patch->lines_deleted;
1975                 show_stats(patch);
1976         }
1977
1978         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
1979 }
1980
1981 static void numstat_patch_list(struct patch *patch)
1982 {
1983         for ( ; patch; patch = patch->next) {
1984                 const char *name;
1985                 name = patch->new_name ? patch->new_name : patch->old_name;
1986                 printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
1987                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
1988                         quote_c_style(name, NULL, stdout, 0);
1989                 else
1990                         fputs(name, stdout);
1991                 putchar('\n');
1992         }
1993 }
1994
1995 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
1996 {
1997         if (mode)
1998                 printf(" %s mode %06o %s\n", newdelete, mode, name);
1999         else
2000                 printf(" %s %s\n", newdelete, name);
2001 }
2002
2003 static void show_mode_change(struct patch *p, int show_name)
2004 {
2005         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2006                 if (show_name)
2007                         printf(" mode change %06o => %06o %s\n",
2008                                p->old_mode, p->new_mode, p->new_name);
2009                 else
2010                         printf(" mode change %06o => %06o\n",
2011                                p->old_mode, p->new_mode);
2012         }
2013 }
2014
2015 static void show_rename_copy(struct patch *p)
2016 {
2017         const char *renamecopy = p->is_rename ? "rename" : "copy";
2018         const char *old, *new;
2019
2020         /* Find common prefix */
2021         old = p->old_name;
2022         new = p->new_name;
2023         while (1) {
2024                 const char *slash_old, *slash_new;
2025                 slash_old = strchr(old, '/');
2026                 slash_new = strchr(new, '/');
2027                 if (!slash_old ||
2028                     !slash_new ||
2029                     slash_old - old != slash_new - new ||
2030                     memcmp(old, new, slash_new - new))
2031                         break;
2032                 old = slash_old + 1;
2033                 new = slash_new + 1;
2034         }
2035         /* p->old_name thru old is the common prefix, and old and new
2036          * through the end of names are renames
2037          */
2038         if (old != p->old_name)
2039                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2040                        (int)(old - p->old_name), p->old_name,
2041                        old, new, p->score);
2042         else
2043                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2044                        p->old_name, p->new_name, p->score);
2045         show_mode_change(p, 0);
2046 }
2047
2048 static void summary_patch_list(struct patch *patch)
2049 {
2050         struct patch *p;
2051
2052         for (p = patch; p; p = p->next) {
2053                 if (p->is_new)
2054                         show_file_mode_name("create", p->new_mode, p->new_name);
2055                 else if (p->is_delete)
2056                         show_file_mode_name("delete", p->old_mode, p->old_name);
2057                 else {
2058                         if (p->is_rename || p->is_copy)
2059                                 show_rename_copy(p);
2060                         else {
2061                                 if (p->score) {
2062                                         printf(" rewrite %s (%d%%)\n",
2063                                                p->new_name, p->score);
2064                                         show_mode_change(p, 0);
2065                                 }
2066                                 else
2067                                         show_mode_change(p, 1);
2068                         }
2069                 }
2070         }
2071 }
2072
2073 static void patch_stats(struct patch *patch)
2074 {
2075         int lines = patch->lines_added + patch->lines_deleted;
2076
2077         if (lines > max_change)
2078                 max_change = lines;
2079         if (patch->old_name) {
2080                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2081                 if (!len)
2082                         len = strlen(patch->old_name);
2083                 if (len > max_len)
2084                         max_len = len;
2085         }
2086         if (patch->new_name) {
2087                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2088                 if (!len)
2089                         len = strlen(patch->new_name);
2090                 if (len > max_len)
2091                         max_len = len;
2092         }
2093 }
2094
2095 static void remove_file(struct patch *patch)
2096 {
2097         if (write_index) {
2098                 if (remove_file_from_cache(patch->old_name) < 0)
2099                         die("unable to remove %s from index", patch->old_name);
2100                 cache_tree_invalidate_path(active_cache_tree, patch->old_name);
2101         }
2102         if (!cached)
2103                 unlink(patch->old_name);
2104 }
2105
2106 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2107 {
2108         struct stat st;
2109         struct cache_entry *ce;
2110         int namelen = strlen(path);
2111         unsigned ce_size = cache_entry_size(namelen);
2112
2113         if (!write_index)
2114                 return;
2115
2116         ce = xcalloc(1, ce_size);
2117         memcpy(ce->name, path, namelen);
2118         ce->ce_mode = create_ce_mode(mode);
2119         ce->ce_flags = htons(namelen);
2120         if (!cached) {
2121                 if (lstat(path, &st) < 0)
2122                         die("unable to stat newly created file %s", path);
2123                 fill_stat_cache_info(ce, &st);
2124         }
2125         if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2126                 die("unable to create backing store for newly created file %s", path);
2127         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2128                 die("unable to add cache entry for %s", path);
2129 }
2130
2131 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2132 {
2133         int fd;
2134
2135         if (S_ISLNK(mode))
2136                 /* Although buf:size is counted string, it also is NUL
2137                  * terminated.
2138                  */
2139                 return symlink(buf, path);
2140         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2141         if (fd < 0)
2142                 return -1;
2143         while (size) {
2144                 int written = xwrite(fd, buf, size);
2145                 if (written < 0)
2146                         die("writing file %s: %s", path, strerror(errno));
2147                 if (!written)
2148                         die("out of space writing file %s", path);
2149                 buf += written;
2150                 size -= written;
2151         }
2152         if (close(fd) < 0)
2153                 die("closing file %s: %s", path, strerror(errno));
2154         return 0;
2155 }
2156
2157 /*
2158  * We optimistically assume that the directories exist,
2159  * which is true 99% of the time anyway. If they don't,
2160  * we create them and try again.
2161  */
2162 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2163 {
2164         if (cached)
2165                 return;
2166         if (!try_create_file(path, mode, buf, size))
2167                 return;
2168
2169         if (errno == ENOENT) {
2170                 if (safe_create_leading_directories(path))
2171                         return;
2172                 if (!try_create_file(path, mode, buf, size))
2173                         return;
2174         }
2175
2176         if (errno == EEXIST || errno == EACCES) {
2177                 /* We may be trying to create a file where a directory
2178                  * used to be.
2179                  */
2180                 struct stat st;
2181                 errno = 0;
2182                 if (!lstat(path, &st) && S_ISDIR(st.st_mode) && !rmdir(path))
2183                         errno = EEXIST;
2184         }
2185
2186         if (errno == EEXIST) {
2187                 unsigned int nr = getpid();
2188
2189                 for (;;) {
2190                         const char *newpath;
2191                         newpath = mkpath("%s~%u", path, nr);
2192                         if (!try_create_file(newpath, mode, buf, size)) {
2193                                 if (!rename(newpath, path))
2194                                         return;
2195                                 unlink(newpath);
2196                                 break;
2197                         }
2198                         if (errno != EEXIST)
2199                                 break;
2200                         ++nr;
2201                 }
2202         }
2203         die("unable to write file %s mode %o", path, mode);
2204 }
2205
2206 static void create_file(struct patch *patch)
2207 {
2208         char *path = patch->new_name;
2209         unsigned mode = patch->new_mode;
2210         unsigned long size = patch->resultsize;
2211         char *buf = patch->result;
2212
2213         if (!mode)
2214                 mode = S_IFREG | 0644;
2215         create_one_file(path, mode, buf, size);
2216         add_index_file(path, mode, buf, size);
2217         cache_tree_invalidate_path(active_cache_tree, path);
2218 }
2219
2220 /* phase zero is to remove, phase one is to create */
2221 static void write_out_one_result(struct patch *patch, int phase)
2222 {
2223         if (patch->is_delete > 0) {
2224                 if (phase == 0)
2225                         remove_file(patch);
2226                 return;
2227         }
2228         if (patch->is_new > 0 || patch->is_copy) {
2229                 if (phase == 1)
2230                         create_file(patch);
2231                 return;
2232         }
2233         /*
2234          * Rename or modification boils down to the same
2235          * thing: remove the old, write the new
2236          */
2237         if (phase == 0)
2238                 remove_file(patch);
2239         if (phase == 1)
2240                 create_file(patch);
2241 }
2242
2243 static int write_out_one_reject(struct patch *patch)
2244 {
2245         FILE *rej;
2246         char namebuf[PATH_MAX];
2247         struct fragment *frag;
2248         int cnt = 0;
2249
2250         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2251                 if (!frag->rejected)
2252                         continue;
2253                 cnt++;
2254         }
2255
2256         if (!cnt)
2257                 return 0;
2258
2259         /* This should not happen, because a removal patch that leaves
2260          * contents are marked "rejected" at the patch level.
2261          */
2262         if (!patch->new_name)
2263                 die("internal error");
2264
2265         cnt = strlen(patch->new_name);
2266         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2267                 cnt = ARRAY_SIZE(namebuf) - 5;
2268                 fprintf(stderr,
2269                         "warning: truncating .rej filename to %.*s.rej",
2270                         cnt - 1, patch->new_name);
2271         }
2272         memcpy(namebuf, patch->new_name, cnt);
2273         memcpy(namebuf + cnt, ".rej", 5);
2274
2275         rej = fopen(namebuf, "w");
2276         if (!rej)
2277                 return error("cannot open %s: %s", namebuf, strerror(errno));
2278
2279         /* Normal git tools never deal with .rej, so do not pretend
2280          * this is a git patch by saying --git nor give extended
2281          * headers.  While at it, maybe please "kompare" that wants
2282          * the trailing TAB and some garbage at the end of line ;-).
2283          */
2284         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2285                 patch->new_name, patch->new_name);
2286         for (cnt = 0, frag = patch->fragments;
2287              frag;
2288              cnt++, frag = frag->next) {
2289                 if (!frag->rejected) {
2290                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2291                         continue;
2292                 }
2293                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2294                 fprintf(rej, "%.*s", frag->size, frag->patch);
2295                 if (frag->patch[frag->size-1] != '\n')
2296                         fputc('\n', rej);
2297         }
2298         fclose(rej);
2299         return -1;
2300 }
2301
2302 static int write_out_results(struct patch *list, int skipped_patch)
2303 {
2304         int phase;
2305         int errs = 0;
2306         struct patch *l;
2307
2308         if (!list && !skipped_patch)
2309                 return error("No changes");
2310
2311         for (phase = 0; phase < 2; phase++) {
2312                 l = list;
2313                 while (l) {
2314                         if (l->rejected)
2315                                 errs = 1;
2316                         else {
2317                                 write_out_one_result(l, phase);
2318                                 if (phase == 1 && write_out_one_reject(l))
2319                                         errs = 1;
2320                         }
2321                         l = l->next;
2322                 }
2323         }
2324         return errs;
2325 }
2326
2327 static struct lock_file lock_file;
2328
2329 static struct excludes {
2330         struct excludes *next;
2331         const char *path;
2332 } *excludes;
2333
2334 static int use_patch(struct patch *p)
2335 {
2336         const char *pathname = p->new_name ? p->new_name : p->old_name;
2337         struct excludes *x = excludes;
2338         while (x) {
2339                 if (fnmatch(x->path, pathname, 0) == 0)
2340                         return 0;
2341                 x = x->next;
2342         }
2343         if (0 < prefix_length) {
2344                 int pathlen = strlen(pathname);
2345                 if (pathlen <= prefix_length ||
2346                     memcmp(prefix, pathname, prefix_length))
2347                         return 0;
2348         }
2349         return 1;
2350 }
2351
2352 static int apply_patch(int fd, const char *filename, int inaccurate_eof)
2353 {
2354         unsigned long offset, size;
2355         char *buffer = read_patch_file(fd, &size);
2356         struct patch *list = NULL, **listp = &list;
2357         int skipped_patch = 0;
2358
2359         patch_input_file = filename;
2360         if (!buffer)
2361                 return -1;
2362         offset = 0;
2363         while (size > 0) {
2364                 struct patch *patch;
2365                 int nr;
2366
2367                 patch = xcalloc(1, sizeof(*patch));
2368                 patch->inaccurate_eof = inaccurate_eof;
2369                 nr = parse_chunk(buffer + offset, size, patch);
2370                 if (nr < 0)
2371                         break;
2372                 if (apply_in_reverse)
2373                         reverse_patches(patch);
2374                 if (use_patch(patch)) {
2375                         patch_stats(patch);
2376                         *listp = patch;
2377                         listp = &patch->next;
2378                 } else {
2379                         /* perhaps free it a bit better? */
2380                         free(patch);
2381                         skipped_patch++;
2382                 }
2383                 offset += nr;
2384                 size -= nr;
2385         }
2386
2387         if (whitespace_error && (new_whitespace == error_on_whitespace))
2388                 apply = 0;
2389
2390         write_index = check_index && apply;
2391         if (write_index && newfd < 0)
2392                 newfd = hold_lock_file_for_update(&lock_file,
2393                                                   get_index_file(), 1);
2394         if (check_index) {
2395                 if (read_cache() < 0)
2396                         die("unable to read index file");
2397         }
2398
2399         if ((check || apply) &&
2400             check_patch_list(list) < 0 &&
2401             !apply_with_reject)
2402                 exit(1);
2403
2404         if (apply && write_out_results(list, skipped_patch))
2405                 exit(1);
2406
2407         if (show_index_info)
2408                 show_index_list(list);
2409
2410         if (diffstat)
2411                 stat_patch_list(list);
2412
2413         if (numstat)
2414                 numstat_patch_list(list);
2415
2416         if (summary)
2417                 summary_patch_list(list);
2418
2419         free(buffer);
2420         return 0;
2421 }
2422
2423 static int git_apply_config(const char *var, const char *value)
2424 {
2425         if (!strcmp(var, "apply.whitespace")) {
2426                 apply_default_whitespace = strdup(value);
2427                 return 0;
2428         }
2429         return git_default_config(var, value);
2430 }
2431
2432
2433 int cmd_apply(int argc, const char **argv, const char *prefix)
2434 {
2435         int i;
2436         int read_stdin = 1;
2437         int inaccurate_eof = 0;
2438         int errs = 0;
2439
2440         const char *whitespace_option = NULL;
2441
2442         for (i = 1; i < argc; i++) {
2443                 const char *arg = argv[i];
2444                 char *end;
2445                 int fd;
2446
2447                 if (!strcmp(arg, "-")) {
2448                         errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2449                         read_stdin = 0;
2450                         continue;
2451                 }
2452                 if (!strncmp(arg, "--exclude=", 10)) {
2453                         struct excludes *x = xmalloc(sizeof(*x));
2454                         x->path = arg + 10;
2455                         x->next = excludes;
2456                         excludes = x;
2457                         continue;
2458                 }
2459                 if (!strncmp(arg, "-p", 2)) {
2460                         p_value = atoi(arg + 2);
2461                         continue;
2462                 }
2463                 if (!strcmp(arg, "--no-add")) {
2464                         no_add = 1;
2465                         continue;
2466                 }
2467                 if (!strcmp(arg, "--stat")) {
2468                         apply = 0;
2469                         diffstat = 1;
2470                         continue;
2471                 }
2472                 if (!strcmp(arg, "--allow-binary-replacement") ||
2473                     !strcmp(arg, "--binary")) {
2474                         allow_binary_replacement = 1;
2475                         continue;
2476                 }
2477                 if (!strcmp(arg, "--numstat")) {
2478                         apply = 0;
2479                         numstat = 1;
2480                         continue;
2481                 }
2482                 if (!strcmp(arg, "--summary")) {
2483                         apply = 0;
2484                         summary = 1;
2485                         continue;
2486                 }
2487                 if (!strcmp(arg, "--check")) {
2488                         apply = 0;
2489                         check = 1;
2490                         continue;
2491                 }
2492                 if (!strcmp(arg, "--index")) {
2493                         check_index = 1;
2494                         continue;
2495                 }
2496                 if (!strcmp(arg, "--cached")) {
2497                         check_index = 1;
2498                         cached = 1;
2499                         continue;
2500                 }
2501                 if (!strcmp(arg, "--apply")) {
2502                         apply = 1;
2503                         continue;
2504                 }
2505                 if (!strcmp(arg, "--index-info")) {
2506                         apply = 0;
2507                         show_index_info = 1;
2508                         continue;
2509                 }
2510                 if (!strcmp(arg, "-z")) {
2511                         line_termination = 0;
2512                         continue;
2513                 }
2514                 if (!strncmp(arg, "-C", 2)) {
2515                         p_context = strtoul(arg + 2, &end, 0);
2516                         if (*end != '\0')
2517                                 die("unrecognized context count '%s'", arg + 2);
2518                         continue;
2519                 }
2520                 if (!strncmp(arg, "--whitespace=", 13)) {
2521                         whitespace_option = arg + 13;
2522                         parse_whitespace_option(arg + 13);
2523                         continue;
2524                 }
2525                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
2526                         apply_in_reverse = 1;
2527                         continue;
2528                 }
2529                 if (!strcmp(arg, "--reject")) {
2530                         apply = apply_with_reject = 1;
2531                         continue;
2532                 }
2533                 if (!strcmp(arg, "--inaccurate-eof")) {
2534                         inaccurate_eof = 1;
2535                         continue;
2536                 }
2537
2538                 if (check_index && prefix_length < 0) {
2539                         prefix = setup_git_directory();
2540                         prefix_length = prefix ? strlen(prefix) : 0;
2541                         git_config(git_apply_config);
2542                         if (!whitespace_option && apply_default_whitespace)
2543                                 parse_whitespace_option(apply_default_whitespace);
2544                 }
2545                 if (0 < prefix_length)
2546                         arg = prefix_filename(prefix, prefix_length, arg);
2547
2548                 fd = open(arg, O_RDONLY);
2549                 if (fd < 0)
2550                         usage(apply_usage);
2551                 read_stdin = 0;
2552                 set_default_whitespace_mode(whitespace_option);
2553                 errs |= apply_patch(fd, arg, inaccurate_eof);
2554                 close(fd);
2555         }
2556         set_default_whitespace_mode(whitespace_option);
2557         if (read_stdin)
2558                 errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2559         if (whitespace_error) {
2560                 if (squelch_whitespace_errors &&
2561                     squelch_whitespace_errors < whitespace_error) {
2562                         int squelched =
2563                                 whitespace_error - squelch_whitespace_errors;
2564                         fprintf(stderr, "warning: squelched %d "
2565                                 "whitespace error%s\n",
2566                                 squelched,
2567                                 squelched == 1 ? "" : "s");
2568                 }
2569                 if (new_whitespace == error_on_whitespace)
2570                         die("%d line%s add%s trailing whitespaces.",
2571                             whitespace_error,
2572                             whitespace_error == 1 ? "" : "s",
2573                             whitespace_error == 1 ? "s" : "");
2574                 if (applied_after_stripping)
2575                         fprintf(stderr, "warning: %d line%s applied after"
2576                                 " stripping trailing whitespaces.\n",
2577                                 applied_after_stripping,
2578                                 applied_after_stripping == 1 ? "" : "s");
2579                 else if (whitespace_error)
2580                         fprintf(stderr, "warning: %d line%s add%s trailing"
2581                                 " whitespaces.\n",
2582                                 whitespace_error,
2583                                 whitespace_error == 1 ? "" : "s",
2584                                 whitespace_error == 1 ? "s" : "");
2585         }
2586
2587         if (write_index) {
2588                 if (write_cache(newfd, active_cache, active_nr) ||
2589                     close(newfd) || commit_lock_file(&lock_file))
2590                         die("Unable to write new index file");
2591         }
2592
2593         return !!errs;
2594 }