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 "cache.h"
  10 #include "cache-tree.h"
  11 #include "quote.h"
  12 #include "blob.h"
  13 #include "delta.h"
  14 #include "builtin.h"
  15 #include "string-list.h"
  16 #include "dir.h"
  17
  18 /*
  19  *  --check turns on checking that the working tree matches the
  20  *    files that are being modified, but doesn't apply the patch
  21  *  --stat does just a diffstat, and doesn't actually apply
  22  *  --numstat does numeric diffstat, and doesn't actually apply
  23  *  --index-info shows the old and new index info for paths if available.
  24  *  --index updates the cache as well.
  25  *  --cached updates only the cache without ever touching the working tree.
  26  */
  27 static const char *prefix;
  28 static int prefix_length = -1;
  29 static int newfd = -1;
  30
  31 static int unidiff_zero;
  32 static int p_value = 1;
  33 static int p_value_known;
  34 static int check_index;
  35 static int update_index;
  36 static int cached;
  37 static int diffstat;
  38 static int numstat;
  39 static int summary;
  40 static int check;
  41 static int apply = 1;
  42 static int apply_in_reverse;
  43 static int apply_with_reject;
  44 static int apply_verbosely;
  45 static int no_add;
  46 static const char *fake_ancestor;
  47 static int line_termination = '\n';
  48 static unsigned long p_context = ULONG_MAX;
  49 static const char apply_usage[] =
  50 "git apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [--verbose] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|fix|error|error-all>] <patch>...";
  51
  52 static enum ws_error_action {
  53         nowarn_ws_error,
  54         warn_on_ws_error,
  55         die_on_ws_error,
  56         correct_ws_error,
  57 } ws_error_action = warn_on_ws_error;
  58 static int whitespace_error;
  59 static int squelch_whitespace_errors = 5;
  60 static int applied_after_fixing_ws;
  61 static const char *patch_input_file;
  62 static const char *root;
  63 static int root_len;
  64
  65 static void parse_whitespace_option(const char *option)
  66 {
  67         if (!option) {
  68                 ws_error_action = warn_on_ws_error;
  69                 return;
  70         }
  71         if (!strcmp(option, "warn")) {
  72                 ws_error_action = warn_on_ws_error;
  73                 return;
  74         }
  75         if (!strcmp(option, "nowarn")) {
  76                 ws_error_action = nowarn_ws_error;
  77                 return;
  78         }
  79         if (!strcmp(option, "error")) {
  80                 ws_error_action = die_on_ws_error;
  81                 return;
  82         }
  83         if (!strcmp(option, "error-all")) {
  84                 ws_error_action = die_on_ws_error;
  85                 squelch_whitespace_errors = 0;
  86                 return;
  87         }
  88         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
  89                 ws_error_action = correct_ws_error;
  90                 return;
  91         }
  92         die("unrecognized whitespace option '%s'", option);
  93 }
  94
  95 static void set_default_whitespace_mode(const char *whitespace_option)
  96 {
  97         if (!whitespace_option && !apply_default_whitespace)
  98                 ws_error_action = (apply ? warn_on_ws_error : nowarn_ws_error);
  99 }
 100
 101 /*
 102  * For "diff-stat" like behaviour, we keep track of the biggest change
 103  * we've seen, and the longest filename. That allows us to do simple
 104  * scaling.
 105  */
 106 static int max_change, max_len;
 107
 108 /*
 109  * Various "current state", notably line numbers and what
 110  * file (and how) we're patching right now.. The "is_xxxx"
 111  * things are flags, where -1 means "don't know yet".
 112  */
 113 static int linenr = 1;
 114
 115 /*
 116  * This represents one "hunk" from a patch, starting with
 117  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 118  * patch text is pointed at by patch, and its byte length
 119  * is stored in size.  leading and trailing are the number
 120  * of context lines.
 121  */
 122 struct fragment {
 123         unsigned long leading, trailing;
 124         unsigned long oldpos, oldlines;
 125         unsigned long newpos, newlines;
 126         const char *patch;
 127         int size;
 128         int rejected;
 129         struct fragment *next;
 130 };
 131
 132 /*
 133  * When dealing with a binary patch, we reuse "leading" field
 134  * to store the type of the binary hunk, either deflated "delta"
 135  * or deflated "literal".
 136  */
 137 #define binary_patch_method leading
 138 #define BINARY_DELTA_DEFLATED   1
 139 #define BINARY_LITERAL_DEFLATED 2
 140
 141 /*
 142  * This represents a "patch" to a file, both metainfo changes
 143  * such as creation/deletion, filemode and content changes represented
 144  * as a series of fragments.
 145  */
 146 struct patch {
 147         char *new_name, *old_name, *def_name;
 148         unsigned int old_mode, new_mode;
 149         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
 150         int rejected;
 151         unsigned ws_rule;
 152         unsigned long deflate_origlen;
 153         int lines_added, lines_deleted;
 154         int score;
 155         unsigned int is_toplevel_relative:1;
 156         unsigned int inaccurate_eof:1;
 157         unsigned int is_binary:1;
 158         unsigned int is_copy:1;
 159         unsigned int is_rename:1;
 160         unsigned int recount:1;
 161         struct fragment *fragments;
 162         char *result;
 163         size_t resultsize;
 164         char old_sha1_prefix[41];
 165         char new_sha1_prefix[41];
 166         struct patch *next;
 167 };
 168
 169 /*
 170  * A line in a file, len-bytes long (includes the terminating LF,
 171  * except for an incomplete line at the end if the file ends with
 172  * one), and its contents hashes to 'hash'.
 173  */
 174 struct line {
 175         size_t len;
 176         unsigned hash : 24;
 177         unsigned flag : 8;
 178 #define LINE_COMMON     1
 179 };
 180
 181 /*
 182  * This represents a "file", which is an array of "lines".
 183  */
 184 struct image {
 185         char *buf;
 186         size_t len;
 187         size_t nr;
 188         size_t alloc;
 189         struct line *line_allocated;
 190         struct line *line;
 191 };
 192
 193 /*
 194  * Records filenames that have been touched, in order to handle
 195  * the case where more than one patches touch the same file.
 196  */
 197
 198 static struct string_list fn_table;
 199
 200 static uint32_t hash_line(const char *cp, size_t len)
 201 {
 202         size_t i;
 203         uint32_t h;
 204         for (i = 0, h = 0; i < len; i++) {
 205                 if (!isspace(cp[i])) {
 206                         h = h * 3 + (cp[i] & 0xff);
 207                 }
 208         }
 209         return h;
 210 }
 211
 212 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
 213 {
 214         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
 215         img->line_allocated[img->nr].len = len;
 216         img->line_allocated[img->nr].hash = hash_line(bol, len);
 217         img->line_allocated[img->nr].flag = flag;
 218         img->nr++;
 219 }
 220
 221 static void prepare_image(struct image *image, char *buf, size_t len,
 222                           int prepare_linetable)
 223 {
 224         const char *cp, *ep;
 225
 226         memset(image, 0, sizeof(*image));
 227         image->buf = buf;
 228         image->len = len;
 229
 230         if (!prepare_linetable)
 231                 return;
 232
 233         ep = image->buf + image->len;
 234         cp = image->buf;
 235         while (cp < ep) {
 236                 const char *next;
 237                 for (next = cp; next < ep && *next != '\n'; next++)
 238                         ;
 239                 if (next < ep)
 240                         next++;
 241                 add_line_info(image, cp, next - cp, 0);
 242                 cp = next;
 243         }
 244         image->line = image->line_allocated;
 245 }
 246
 247 static void clear_image(struct image *image)
 248 {
 249         free(image->buf);
 250         image->buf = NULL;
 251         image->len = 0;
 252 }
 253
 254 static void say_patch_name(FILE *output, const char *pre,
 255                            struct patch *patch, const char *post)
 256 {
 257         fputs(pre, output);
 258         if (patch->old_name && patch->new_name &&
 259             strcmp(patch->old_name, patch->new_name)) {
 260                 quote_c_style(patch->old_name, NULL, output, 0);
 261                 fputs(" => ", output);
 262                 quote_c_style(patch->new_name, NULL, output, 0);
 263         } else {
 264                 const char *n = patch->new_name;
 265                 if (!n)
 266                         n = patch->old_name;
 267                 quote_c_style(n, NULL, output, 0);
 268         }
 269         fputs(post, output);
 270 }
 271
 272 #define CHUNKSIZE (8192)
 273 #define SLOP (16)
 274
 275 static void read_patch_file(struct strbuf *sb, int fd)
 276 {
 277         if (strbuf_read(sb, fd, 0) < 0)
 278                 die("git apply: read returned %s", strerror(errno));
 279
 280         /*
 281          * Make sure that we have some slop in the buffer
 282          * so that we can do speculative "memcmp" etc, and
 283          * see to it that it is NUL-filled.
 284          */
 285         strbuf_grow(sb, SLOP);
 286         memset(sb->buf + sb->len, 0, SLOP);
 287 }
 288
 289 static unsigned long linelen(const char *buffer, unsigned long size)
 290 {
 291         unsigned long len = 0;
 292         while (size--) {
 293                 len++;
 294                 if (*buffer++ == '\n')
 295                         break;
 296         }
 297         return len;
 298 }
 299
 300 static int is_dev_null(const char *str)
 301 {
 302         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
 303 }
 304
 305 #define TERM_SPACE      1
 306 #define TERM_TAB        2
 307
 308 static int name_terminate(const char *name, int namelen, int c, int terminate)
 309 {
 310         if (c == ' ' && !(terminate & TERM_SPACE))
 311                 return 0;
 312         if (c == '\t' && !(terminate & TERM_TAB))
 313                 return 0;
 314
 315         return 1;
 316 }
 317
 318 static char *find_name(const char *line, char *def, int p_value, int terminate)
 319 {
 320         int len;
 321         const char *start = line;
 322
 323         if (*line == '"') {
 324                 struct strbuf name = STRBUF_INIT;
 325
 326                 /*
 327                  * Proposed "new-style" GNU patch/diff format; see
 328                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
 329                  */
 330                 if (!unquote_c_style(&name, line, NULL)) {
 331                         char *cp;
 332
 333                         for (cp = name.buf; p_value; p_value--) {
 334                                 cp = strchr(cp, '/');
 335                                 if (!cp)
 336                                         break;
 337                                 cp++;
 338                         }
 339                         if (cp) {
 340                                 /* name can later be freed, so we need
 341                                  * to memmove, not just return cp
 342                                  */
 343                                 strbuf_remove(&name, 0, cp - name.buf);
 344                                 free(def);
 345                                 if (root)
 346                                         strbuf_insert(&name, 0, root, root_len);
 347                                 return strbuf_detach(&name, NULL);
 348                         }
 349                 }
 350                 strbuf_release(&name);
 351         }
 352
 353         for (;;) {
 354                 char c = *line;
 355
 356                 if (isspace(c)) {
 357                         if (c == '\n')
 358                                 break;
 359                         if (name_terminate(start, line-start, c, terminate))
 360                                 break;
 361                 }
 362                 line++;
 363                 if (c == '/' && !--p_value)
 364                         start = line;
 365         }
 366         if (!start)
 367                 return def;
 368         len = line - start;
 369         if (!len)
 370                 return def;
 371
 372         /*
 373          * Generally we prefer the shorter name, especially
 374          * if the other one is just a variation of that with
 375          * something else tacked on to the end (ie "file.orig"
 376          * or "file~").
 377          */
 378         if (def) {
 379                 int deflen = strlen(def);
 380                 if (deflen < len && !strncmp(start, def, deflen))
 381                         return def;
 382                 free(def);
 383         }
 384
 385         if (root) {
 386                 char *ret = xmalloc(root_len + len + 1);
 387                 strcpy(ret, root);
 388                 memcpy(ret + root_len, start, len);
 389                 ret[root_len + len] = '\0';
 390                 return ret;
 391         }
 392
 393         return xmemdupz(start, len);
 394 }
 395
 396 static int count_slashes(const char *cp)
 397 {
 398         int cnt = 0;
 399         char ch;
 400
 401         while ((ch = *cp++))
 402                 if (ch == '/')
 403                         cnt++;
 404         return cnt;
 405 }
 406
 407 /*
 408  * Given the string after "--- " or "+++ ", guess the appropriate
 409  * p_value for the given patch.
 410  */
 411 static int guess_p_value(const char *nameline)
 412 {
 413         char *name, *cp;
 414         int val = -1;
 415
 416         if (is_dev_null(nameline))
 417                 return -1;
 418         name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
 419         if (!name)
 420                 return -1;
 421         cp = strchr(name, '/');
 422         if (!cp)
 423                 val = 0;
 424         else if (prefix) {
 425                 /*
 426                  * Does it begin with "a/$our-prefix" and such?  Then this is
 427                  * very likely to apply to our directory.
 428                  */
 429                 if (!strncmp(name, prefix, prefix_length))
 430                         val = count_slashes(prefix);
 431                 else {
 432                         cp++;
 433                         if (!strncmp(cp, prefix, prefix_length))
 434                                 val = count_slashes(prefix) + 1;
 435                 }
 436         }
 437         free(name);
 438         return val;
 439 }
 440
 441 /*
 442  * Get the name etc info from the ---/+++ lines of a traditional patch header
 443  *
 444  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 445  * files, we can happily check the index for a match, but for creating a
 446  * new file we should try to match whatever "patch" does. I have no idea.
 447  */
 448 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
 449 {
 450         char *name;
 451
 452         first += 4;     /* skip "--- " */
 453         second += 4;    /* skip "+++ " */
 454         if (!p_value_known) {
 455                 int p, q;
 456                 p = guess_p_value(first);
 457                 q = guess_p_value(second);
 458                 if (p < 0) p = q;
 459                 if (0 <= p && p == q) {
 460                         p_value = p;
 461                         p_value_known = 1;
 462                 }
 463         }
 464         if (is_dev_null(first)) {
 465                 patch->is_new = 1;
 466                 patch->is_delete = 0;
 467                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
 468                 patch->new_name = name;
 469         } else if (is_dev_null(second)) {
 470                 patch->is_new = 0;
 471                 patch->is_delete = 1;
 472                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 473                 patch->old_name = name;
 474         } else {
 475                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 476                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
 477                 patch->old_name = patch->new_name = name;
 478         }
 479         if (!name)
 480                 die("unable to find filename in patch at line %d", linenr);
 481 }
 482
 483 static int gitdiff_hdrend(const char *line, struct patch *patch)
 484 {
 485         return -1;
 486 }
 487
 488 /*
 489  * We're anal about diff header consistency, to make
 490  * sure that we don't end up having strange ambiguous
 491  * patches floating around.
 492  *
 493  * As a result, gitdiff_{old|new}name() will check
 494  * their names against any previous information, just
 495  * to make sure..
 496  */
 497 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
 498 {
 499         if (!orig_name && !isnull)
 500                 return find_name(line, NULL, p_value, TERM_TAB);
 501
 502         if (orig_name) {
 503                 int len;
 504                 const char *name;
 505                 char *another;
 506                 name = orig_name;
 507                 len = strlen(name);
 508                 if (isnull)
 509                         die("git apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
 510                 another = find_name(line, NULL, p_value, TERM_TAB);
 511                 if (!another || memcmp(another, name, len))
 512                         die("git apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
 513                 free(another);
 514                 return orig_name;
 515         }
 516         else {
 517                 /* expect "/dev/null" */
 518                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
 519                         die("git apply: bad git-diff - expected /dev/null on line %d", linenr);
 520                 return NULL;
 521         }
 522 }
 523
 524 static int gitdiff_oldname(const char *line, struct patch *patch)
 525 {
 526         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
 527         return 0;
 528 }
 529
 530 static int gitdiff_newname(const char *line, struct patch *patch)
 531 {
 532         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
 533         return 0;
 534 }
 535
 536 static int gitdiff_oldmode(const char *line, struct patch *patch)
 537 {
 538         patch->old_mode = strtoul(line, NULL, 8);
 539         return 0;
 540 }
 541
 542 static int gitdiff_newmode(const char *line, struct patch *patch)
 543 {
 544         patch->new_mode = strtoul(line, NULL, 8);
 545         return 0;
 546 }
 547
 548 static int gitdiff_delete(const char *line, struct patch *patch)
 549 {
 550         patch->is_delete = 1;
 551         patch->old_name = patch->def_name;
 552         return gitdiff_oldmode(line, patch);
 553 }
 554
 555 static int gitdiff_newfile(const char *line, struct patch *patch)
 556 {
 557         patch->is_new = 1;
 558         patch->new_name = patch->def_name;
 559         return gitdiff_newmode(line, patch);
 560 }
 561
 562 static int gitdiff_copysrc(const char *line, struct patch *patch)
 563 {
 564         patch->is_copy = 1;
 565         patch->old_name = find_name(line, NULL, 0, 0);
 566         return 0;
 567 }
 568
 569 static int gitdiff_copydst(const char *line, struct patch *patch)
 570 {
 571         patch->is_copy = 1;
 572         patch->new_name = find_name(line, NULL, 0, 0);
 573         return 0;
 574 }
 575
 576 static int gitdiff_renamesrc(const char *line, struct patch *patch)
 577 {
 578         patch->is_rename = 1;
 579         patch->old_name = find_name(line, NULL, 0, 0);
 580         return 0;
 581 }
 582
 583 static int gitdiff_renamedst(const char *line, struct patch *patch)
 584 {
 585         patch->is_rename = 1;
 586         patch->new_name = find_name(line, NULL, 0, 0);
 587         return 0;
 588 }
 589
 590 static int gitdiff_similarity(const char *line, struct patch *patch)
 591 {
 592         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 593                 patch->score = 0;
 594         return 0;
 595 }
 596
 597 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
 598 {
 599         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 600                 patch->score = 0;
 601         return 0;
 602 }
 603
 604 static int gitdiff_index(const char *line, struct patch *patch)
 605 {
 606         /*
 607          * index line is N hexadecimal, "..", N hexadecimal,
 608          * and optional space with octal mode.
 609          */
 610         const char *ptr, *eol;
 611         int len;
 612
 613         ptr = strchr(line, '.');
 614         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
 615                 return 0;
 616         len = ptr - line;
 617         memcpy(patch->old_sha1_prefix, line, len);
 618         patch->old_sha1_prefix[len] = 0;
 619
 620         line = ptr + 2;
 621         ptr = strchr(line, ' ');
 622         eol = strchr(line, '\n');
 623
 624         if (!ptr || eol < ptr)
 625                 ptr = eol;
 626         len = ptr - line;
 627
 628         if (40 < len)
 629                 return 0;
 630         memcpy(patch->new_sha1_prefix, line, len);
 631         patch->new_sha1_prefix[len] = 0;
 632         if (*ptr == ' ')
 633                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
 634         return 0;
 635 }
 636
 637 /*
 638  * This is normal for a diff that doesn't change anything: we'll fall through
 639  * into the next diff. Tell the parser to break out.
 640  */
 641 static int gitdiff_unrecognized(const char *line, struct patch *patch)
 642 {
 643         return -1;
 644 }
 645
 646 static const char *stop_at_slash(const char *line, int llen)
 647 {
 648         int i;
 649
 650         for (i = 0; i < llen; i++) {
 651                 int ch = line[i];
 652                 if (ch == '/')
 653                         return line + i;
 654         }
 655         return NULL;
 656 }
 657
 658 /*
 659  * This is to extract the same name that appears on "diff --git"
 660  * line.  We do not find and return anything if it is a rename
 661  * patch, and it is OK because we will find the name elsewhere.
 662  * We need to reliably find name only when it is mode-change only,
 663  * creation or deletion of an empty file.  In any of these cases,
 664  * both sides are the same name under a/ and b/ respectively.
 665  */
 666 static char *git_header_name(char *line, int llen)
 667 {
 668         const char *name;
 669         const char *second = NULL;
 670         size_t len;
 671
 672         line += strlen("diff --git ");
 673         llen -= strlen("diff --git ");
 674
 675         if (*line == '"') {
 676                 const char *cp;
 677                 struct strbuf first = STRBUF_INIT;
 678                 struct strbuf sp = STRBUF_INIT;
 679
 680                 if (unquote_c_style(&first, line, &second))
 681                         goto free_and_fail1;
 682
 683                 /* advance to the first slash */
 684                 cp = stop_at_slash(first.buf, first.len);
 685                 /* we do not accept absolute paths */
 686                 if (!cp || cp == first.buf)
 687                         goto free_and_fail1;
 688                 strbuf_remove(&first, 0, cp + 1 - first.buf);
 689
 690                 /*
 691                  * second points at one past closing dq of name.
 692                  * find the second name.
 693                  */
 694                 while ((second < line + llen) && isspace(*second))
 695                         second++;
 696
 697                 if (line + llen <= second)
 698                         goto free_and_fail1;
 699                 if (*second == '"') {
 700                         if (unquote_c_style(&sp, second, NULL))
 701                                 goto free_and_fail1;
 702                         cp = stop_at_slash(sp.buf, sp.len);
 703                         if (!cp || cp == sp.buf)
 704                                 goto free_and_fail1;
 705                         /* They must match, otherwise ignore */
 706                         if (strcmp(cp + 1, first.buf))
 707                                 goto free_and_fail1;
 708                         strbuf_release(&sp);
 709                         return strbuf_detach(&first, NULL);
 710                 }
 711
 712                 /* unquoted second */
 713                 cp = stop_at_slash(second, line + llen - second);
 714                 if (!cp || cp == second)
 715                         goto free_and_fail1;
 716                 cp++;
 717                 if (line + llen - cp != first.len + 1 ||
 718                     memcmp(first.buf, cp, first.len))
 719                         goto free_and_fail1;
 720                 return strbuf_detach(&first, NULL);
 721
 722         free_and_fail1:
 723                 strbuf_release(&first);
 724                 strbuf_release(&sp);
 725                 return NULL;
 726         }
 727
 728         /* unquoted first name */
 729         name = stop_at_slash(line, llen);
 730         if (!name || name == line)
 731                 return NULL;
 732         name++;
 733
 734         /*
 735          * since the first name is unquoted, a dq if exists must be
 736          * the beginning of the second name.
 737          */
 738         for (second = name; second < line + llen; second++) {
 739                 if (*second == '"') {
 740                         struct strbuf sp = STRBUF_INIT;
 741                         const char *np;
 742
 743                         if (unquote_c_style(&sp, second, NULL))
 744                                 goto free_and_fail2;
 745
 746                         np = stop_at_slash(sp.buf, sp.len);
 747                         if (!np || np == sp.buf)
 748                                 goto free_and_fail2;
 749                         np++;
 750
 751                         len = sp.buf + sp.len - np;
 752                         if (len < second - name &&
 753                             !strncmp(np, name, len) &&
 754                             isspace(name[len])) {
 755                                 /* Good */
 756                                 strbuf_remove(&sp, 0, np - sp.buf);
 757                                 return strbuf_detach(&sp, NULL);
 758                         }
 759
 760                 free_and_fail2:
 761                         strbuf_release(&sp);
 762                         return NULL;
 763                 }
 764         }
 765
 766         /*
 767          * Accept a name only if it shows up twice, exactly the same
 768          * form.
 769          */
 770         for (len = 0 ; ; len++) {
 771                 switch (name[len]) {
 772                 default:
 773                         continue;
 774                 case '\n':
 775                         return NULL;
 776                 case '\t': case ' ':
 777                         second = name+len;
 778                         for (;;) {
 779                                 char c = *second++;
 780                                 if (c == '\n')
 781                                         return NULL;
 782                                 if (c == '/')
 783                                         break;
 784                         }
 785                         if (second[len] == '\n' && !memcmp(name, second, len)) {
 786                                 return xmemdupz(name, len);
 787                         }
 788                 }
 789         }
 790 }
 791
 792 /* Verify that we recognize the lines following a git header */
 793 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
 794 {
 795         unsigned long offset;
 796
 797         /* A git diff has explicit new/delete information, so we don't guess */
 798         patch->is_new = 0;
 799         patch->is_delete = 0;
 800
 801         /*
 802          * Some things may not have the old name in the
 803          * rest of the headers anywhere (pure mode changes,
 804          * or removing or adding empty files), so we get
 805          * the default name from the header.
 806          */
 807         patch->def_name = git_header_name(line, len);
 808
 809         line += len;
 810         size -= len;
 811         linenr++;
 812         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
 813                 static const struct opentry {
 814                         const char *str;
 815                         int (*fn)(const char *, struct patch *);
 816                 } optable[] = {
 817                         { "@@ -", gitdiff_hdrend },
 818                         { "--- ", gitdiff_oldname },
 819                         { "+++ ", gitdiff_newname },
 820                         { "old mode ", gitdiff_oldmode },
 821                         { "new mode ", gitdiff_newmode },
 822                         { "deleted file mode ", gitdiff_delete },
 823                         { "new file mode ", gitdiff_newfile },
 824                         { "copy from ", gitdiff_copysrc },
 825                         { "copy to ", gitdiff_copydst },
 826                         { "rename old ", gitdiff_renamesrc },
 827                         { "rename new ", gitdiff_renamedst },
 828                         { "rename from ", gitdiff_renamesrc },
 829                         { "rename to ", gitdiff_renamedst },
 830                         { "similarity index ", gitdiff_similarity },
 831                         { "dissimilarity index ", gitdiff_dissimilarity },
 832                         { "index ", gitdiff_index },
 833                         { "", gitdiff_unrecognized },
 834                 };
 835                 int i;
 836
 837                 len = linelen(line, size);
 838                 if (!len || line[len-1] != '\n')
 839                         break;
 840                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
 841                         const struct opentry *p = optable + i;
 842                         int oplen = strlen(p->str);
 843                         if (len < oplen || memcmp(p->str, line, oplen))
 844                                 continue;
 845                         if (p->fn(line + oplen, patch) < 0)
 846                                 return offset;
 847                         break;
 848                 }
 849         }
 850
 851         return offset;
 852 }
 853
 854 static int parse_num(const char *line, unsigned long *p)
 855 {
 856         char *ptr;
 857
 858         if (!isdigit(*line))
 859                 return 0;
 860         *p = strtoul(line, &ptr, 10);
 861         return ptr - line;
 862 }
 863
 864 static int parse_range(const char *line, int len, int offset, const char *expect,
 865                        unsigned long *p1, unsigned long *p2)
 866 {
 867         int digits, ex;
 868
 869         if (offset < 0 || offset >= len)
 870                 return -1;
 871         line += offset;
 872         len -= offset;
 873
 874         digits = parse_num(line, p1);
 875         if (!digits)
 876                 return -1;
 877
 878         offset += digits;
 879         line += digits;
 880         len -= digits;
 881
 882         *p2 = 1;
 883         if (*line == ',') {
 884                 digits = parse_num(line+1, p2);
 885                 if (!digits)
 886                         return -1;
 887
 888                 offset += digits+1;
 889                 line += digits+1;
 890                 len -= digits+1;
 891         }
 892
 893         ex = strlen(expect);
 894         if (ex > len)
 895                 return -1;
 896         if (memcmp(line, expect, ex))
 897                 return -1;
 898
 899         return offset + ex;
 900 }
 901
 902 static void recount_diff(char *line, int size, struct fragment *fragment)
 903 {
 904         int oldlines = 0, newlines = 0, ret = 0;
 905
 906         if (size < 1) {
 907                 warning("recount: ignore empty hunk");
 908                 return;
 909         }
 910
 911         for (;;) {
 912                 int len = linelen(line, size);
 913                 size -= len;
 914                 line += len;
 915
 916                 if (size < 1)
 917                         break;
 918
 919                 switch (*line) {
 920                 case ' ': case '\n':
 921                         newlines++;
 922                         /* fall through */
 923                 case '-':
 924                         oldlines++;
 925                         continue;
 926                 case '+':
 927                         newlines++;
 928                         continue;
 929                 case '\\':
 930                         continue;
 931                 case '@':
 932                         ret = size < 3 || prefixcmp(line, "@@ ");
 933                         break;
 934                 case 'd':
 935                         ret = size < 5 || prefixcmp(line, "diff ");
 936                         break;
 937                 default:
 938                         ret = -1;
 939                         break;
 940                 }
 941                 if (ret) {
 942                         warning("recount: unexpected line: %.*s",
 943                                 (int)linelen(line, size), line);
 944                         return;
 945                 }
 946                 break;
 947         }
 948         fragment->oldlines = oldlines;
 949         fragment->newlines = newlines;
 950 }
 951
 952 /*
 953  * Parse a unified diff fragment header of the
 954  * form "@@ -a,b +c,d @@"
 955  */
 956 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
 957 {
 958         int offset;
 959
 960         if (!len || line[len-1] != '\n')
 961                 return -1;
 962
 963         /* Figure out the number of lines in a fragment */
 964         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
 965         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 966
 967         return offset;
 968 }
 969
 970 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
 971 {
 972         unsigned long offset, len;
 973
 974         patch->is_toplevel_relative = 0;
 975         patch->is_rename = patch->is_copy = 0;
 976         patch->is_new = patch->is_delete = -1;
 977         patch->old_mode = patch->new_mode = 0;
 978         patch->old_name = patch->new_name = NULL;
 979         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
 980                 unsigned long nextlen;
 981
 982                 len = linelen(line, size);
 983                 if (!len)
 984                         break;
 985
 986                 /* Testing this early allows us to take a few shortcuts.. */
 987                 if (len < 6)
 988                         continue;
 989
 990                 /*
 991                  * Make sure we don't find any unconnected patch fragments.
 992                  * That's a sign that we didn't find a header, and that a
 993                  * patch has become corrupted/broken up.
 994                  */
 995                 if (!memcmp("@@ -", line, 4)) {
 996                         struct fragment dummy;
 997                         if (parse_fragment_header(line, len, &dummy) < 0)
 998                                 continue;
 999                         die("patch fragment without header at line %d: %.*s",
1000                             linenr, (int)len-1, line);
1001                 }
1002
1003                 if (size < len + 6)
1004                         break;
1005
1006                 /*
1007                  * Git patch? It might not have a real patch, just a rename
1008                  * or mode change, so we handle that specially
1009                  */
1010                 if (!memcmp("diff --git ", line, 11)) {
1011                         int git_hdr_len = parse_git_header(line, len, size, patch);
1012                         if (git_hdr_len <= len)
1013                                 continue;
1014                         if (!patch->old_name && !patch->new_name) {
1015                                 if (!patch->def_name)
1016                                         die("git diff header lacks filename information (line %d)", linenr);
1017                                 patch->old_name = patch->new_name = patch->def_name;
1018                         }
1019                         patch->is_toplevel_relative = 1;
1020                         *hdrsize = git_hdr_len;
1021                         return offset;
1022                 }
1023
1024                 /* --- followed by +++ ? */
1025                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1026                         continue;
1027
1028                 /*
1029                  * We only accept unified patches, so we want it to
1030                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1031                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1032                  */
1033                 nextlen = linelen(line + len, size - len);
1034                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1035                         continue;
1036
1037                 /* Ok, we'll consider it a patch */
1038                 parse_traditional_patch(line, line+len, patch);
1039                 *hdrsize = len + nextlen;
1040                 linenr += 2;
1041                 return offset;
1042         }
1043         return -1;
1044 }
1045
1046 static void check_whitespace(const char *line, int len, unsigned ws_rule)
1047 {
1048         char *err;
1049         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1050         if (!result)
1051                 return;
1052
1053         whitespace_error++;
1054         if (squelch_whitespace_errors &&
1055             squelch_whitespace_errors < whitespace_error)
1056                 ;
1057         else {
1058                 err = whitespace_error_string(result);
1059                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1060                         patch_input_file, linenr, err, len - 2, line + 1);
1061                 free(err);
1062         }
1063 }
1064
1065 /*
1066  * Parse a unified diff. Note that this really needs to parse each
1067  * fragment separately, since the only way to know the difference
1068  * between a "---" that is part of a patch, and a "---" that starts
1069  * the next patch is to look at the line counts..
1070  */
1071 static int parse_fragment(char *line, unsigned long size,
1072                           struct patch *patch, struct fragment *fragment)
1073 {
1074         int added, deleted;
1075         int len = linelen(line, size), offset;
1076         unsigned long oldlines, newlines;
1077         unsigned long leading, trailing;
1078
1079         offset = parse_fragment_header(line, len, fragment);
1080         if (offset < 0)
1081                 return -1;
1082         if (offset > 0 && patch->recount)
1083                 recount_diff(line + offset, size - offset, fragment);
1084         oldlines = fragment->oldlines;
1085         newlines = fragment->newlines;
1086         leading = 0;
1087         trailing = 0;
1088
1089         /* Parse the thing.. */
1090         line += len;
1091         size -= len;
1092         linenr++;
1093         added = deleted = 0;
1094         for (offset = len;
1095              0 < size;
1096              offset += len, size -= len, line += len, linenr++) {
1097                 if (!oldlines && !newlines)
1098                         break;
1099                 len = linelen(line, size);
1100                 if (!len || line[len-1] != '\n')
1101                         return -1;
1102                 switch (*line) {
1103                 default:
1104                         return -1;
1105                 case '\n': /* newer GNU diff, an empty context line */
1106                 case ' ':
1107                         oldlines--;
1108                         newlines--;
1109                         if (!deleted && !added)
1110                                 leading++;
1111                         trailing++;
1112                         break;
1113                 case '-':
1114                         if (apply_in_reverse &&
1115                             ws_error_action != nowarn_ws_error)
1116                                 check_whitespace(line, len, patch->ws_rule);
1117                         deleted++;
1118                         oldlines--;
1119                         trailing = 0;
1120                         break;
1121                 case '+':
1122                         if (!apply_in_reverse &&
1123                             ws_error_action != nowarn_ws_error)
1124                                 check_whitespace(line, len, patch->ws_rule);
1125                         added++;
1126                         newlines--;
1127                         trailing = 0;
1128                         break;
1129
1130                 /*
1131                  * We allow "\ No newline at end of file". Depending
1132                  * on locale settings when the patch was produced we
1133                  * don't know what this line looks like. The only
1134                  * thing we do know is that it begins with "\ ".
1135                  * Checking for 12 is just for sanity check -- any
1136                  * l10n of "\ No newline..." is at least that long.
1137                  */
1138                 case '\\':
1139                         if (len < 12 || memcmp(line, "\\ ", 2))
1140                                 return -1;
1141                         break;
1142                 }
1143         }
1144         if (oldlines || newlines)
1145                 return -1;
1146         fragment->leading = leading;
1147         fragment->trailing = trailing;
1148
1149         /*
1150          * If a fragment ends with an incomplete line, we failed to include
1151          * it in the above loop because we hit oldlines == newlines == 0
1152          * before seeing it.
1153          */
1154         if (12 < size && !memcmp(line, "\\ ", 2))
1155                 offset += linelen(line, size);
1156
1157         patch->lines_added += added;
1158         patch->lines_deleted += deleted;
1159
1160         if (0 < patch->is_new && oldlines)
1161                 return error("new file depends on old contents");
1162         if (0 < patch->is_delete && newlines)
1163                 return error("deleted file still has contents");
1164         return offset;
1165 }
1166
1167 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1168 {
1169         unsigned long offset = 0;
1170         unsigned long oldlines = 0, newlines = 0, context = 0;
1171         struct fragment **fragp = &patch->fragments;
1172
1173         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1174                 struct fragment *fragment;
1175                 int len;
1176
1177                 fragment = xcalloc(1, sizeof(*fragment));
1178                 len = parse_fragment(line, size, patch, fragment);
1179                 if (len <= 0)
1180                         die("corrupt patch at line %d", linenr);
1181                 fragment->patch = line;
1182                 fragment->size = len;
1183                 oldlines += fragment->oldlines;
1184                 newlines += fragment->newlines;
1185                 context += fragment->leading + fragment->trailing;
1186
1187                 *fragp = fragment;
1188                 fragp = &fragment->next;
1189
1190                 offset += len;
1191                 line += len;
1192                 size -= len;
1193         }
1194
1195         /*
1196          * If something was removed (i.e. we have old-lines) it cannot
1197          * be creation, and if something was added it cannot be
1198          * deletion.  However, the reverse is not true; --unified=0
1199          * patches that only add are not necessarily creation even
1200          * though they do not have any old lines, and ones that only
1201          * delete are not necessarily deletion.
1202          *
1203          * Unfortunately, a real creation/deletion patch do _not_ have
1204          * any context line by definition, so we cannot safely tell it
1205          * apart with --unified=0 insanity.  At least if the patch has
1206          * more than one hunk it is not creation or deletion.
1207          */
1208         if (patch->is_new < 0 &&
1209             (oldlines || (patch->fragments && patch->fragments->next)))
1210                 patch->is_new = 0;
1211         if (patch->is_delete < 0 &&
1212             (newlines || (patch->fragments && patch->fragments->next)))
1213                 patch->is_delete = 0;
1214
1215         if (0 < patch->is_new && oldlines)
1216                 die("new file %s depends on old contents", patch->new_name);
1217         if (0 < patch->is_delete && newlines)
1218                 die("deleted file %s still has contents", patch->old_name);
1219         if (!patch->is_delete && !newlines && context)
1220                 fprintf(stderr, "** warning: file %s becomes empty but "
1221                         "is not deleted\n", patch->new_name);
1222
1223         return offset;
1224 }
1225
1226 static inline int metadata_changes(struct patch *patch)
1227 {
1228         return  patch->is_rename > 0 ||
1229                 patch->is_copy > 0 ||
1230                 patch->is_new > 0 ||
1231                 patch->is_delete ||
1232                 (patch->old_mode && patch->new_mode &&
1233                  patch->old_mode != patch->new_mode);
1234 }
1235
1236 static char *inflate_it(const void *data, unsigned long size,
1237                         unsigned long inflated_size)
1238 {
1239         z_stream stream;
1240         void *out;
1241         int st;
1242
1243         memset(&stream, 0, sizeof(stream));
1244
1245         stream.next_in = (unsigned char *)data;
1246         stream.avail_in = size;
1247         stream.next_out = out = xmalloc(inflated_size);
1248         stream.avail_out = inflated_size;
1249         inflateInit(&stream);
1250         st = inflate(&stream, Z_FINISH);
1251         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1252                 free(out);
1253                 return NULL;
1254         }
1255         return out;
1256 }
1257
1258 static struct fragment *parse_binary_hunk(char **buf_p,
1259                                           unsigned long *sz_p,
1260                                           int *status_p,
1261                                           int *used_p)
1262 {
1263         /*
1264          * Expect a line that begins with binary patch method ("literal"
1265          * or "delta"), followed by the length of data before deflating.
1266          * a sequence of 'length-byte' followed by base-85 encoded data
1267          * should follow, terminated by a newline.
1268          *
1269          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1270          * and we would limit the patch line to 66 characters,
1271          * so one line can fit up to 13 groups that would decode
1272          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1273          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1274          */
1275         int llen, used;
1276         unsigned long size = *sz_p;
1277         char *buffer = *buf_p;
1278         int patch_method;
1279         unsigned long origlen;
1280         char *data = NULL;
1281         int hunk_size = 0;
1282         struct fragment *frag;
1283
1284         llen = linelen(buffer, size);
1285         used = llen;
1286
1287         *status_p = 0;
1288
1289         if (!prefixcmp(buffer, "delta ")) {
1290                 patch_method = BINARY_DELTA_DEFLATED;
1291                 origlen = strtoul(buffer + 6, NULL, 10);
1292         }
1293         else if (!prefixcmp(buffer, "literal ")) {
1294                 patch_method = BINARY_LITERAL_DEFLATED;
1295                 origlen = strtoul(buffer + 8, NULL, 10);
1296         }
1297         else
1298                 return NULL;
1299
1300         linenr++;
1301         buffer += llen;
1302         while (1) {
1303                 int byte_length, max_byte_length, newsize;
1304                 llen = linelen(buffer, size);
1305                 used += llen;
1306                 linenr++;
1307                 if (llen == 1) {
1308                         /* consume the blank line */
1309                         buffer++;
1310                         size--;
1311                         break;
1312                 }
1313                 /*
1314                  * Minimum line is "A00000\n" which is 7-byte long,
1315                  * and the line length must be multiple of 5 plus 2.
1316                  */
1317                 if ((llen < 7) || (llen-2) % 5)
1318                         goto corrupt;
1319                 max_byte_length = (llen - 2) / 5 * 4;
1320                 byte_length = *buffer;
1321                 if ('A' <= byte_length && byte_length <= 'Z')
1322                         byte_length = byte_length - 'A' + 1;
1323                 else if ('a' <= byte_length && byte_length <= 'z')
1324                         byte_length = byte_length - 'a' + 27;
1325                 else
1326                         goto corrupt;
1327                 /* if the input length was not multiple of 4, we would
1328                  * have filler at the end but the filler should never
1329                  * exceed 3 bytes
1330                  */
1331                 if (max_byte_length < byte_length ||
1332                     byte_length <= max_byte_length - 4)
1333                         goto corrupt;
1334                 newsize = hunk_size + byte_length;
1335                 data = xrealloc(data, newsize);
1336                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1337                         goto corrupt;
1338                 hunk_size = newsize;
1339                 buffer += llen;
1340                 size -= llen;
1341         }
1342
1343         frag = xcalloc(1, sizeof(*frag));
1344         frag->patch = inflate_it(data, hunk_size, origlen);
1345         if (!frag->patch)
1346                 goto corrupt;
1347         free(data);
1348         frag->size = origlen;
1349         *buf_p = buffer;
1350         *sz_p = size;
1351         *used_p = used;
1352         frag->binary_patch_method = patch_method;
1353         return frag;
1354
1355  corrupt:
1356         free(data);
1357         *status_p = -1;
1358         error("corrupt binary patch at line %d: %.*s",
1359               linenr-1, llen-1, buffer);
1360         return NULL;
1361 }
1362
1363 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1364 {
1365         /*
1366          * We have read "GIT binary patch\n"; what follows is a line
1367          * that says the patch method (currently, either "literal" or
1368          * "delta") and the length of data before deflating; a
1369          * sequence of 'length-byte' followed by base-85 encoded data
1370          * follows.
1371          *
1372          * When a binary patch is reversible, there is another binary
1373          * hunk in the same format, starting with patch method (either
1374          * "literal" or "delta") with the length of data, and a sequence
1375          * of length-byte + base-85 encoded data, terminated with another
1376          * empty line.  This data, when applied to the postimage, produces
1377          * the preimage.
1378          */
1379         struct fragment *forward;
1380         struct fragment *reverse;
1381         int status;
1382         int used, used_1;
1383
1384         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1385         if (!forward && !status)
1386                 /* there has to be one hunk (forward hunk) */
1387                 return error("unrecognized binary patch at line %d", linenr-1);
1388         if (status)
1389                 /* otherwise we already gave an error message */
1390                 return status;
1391
1392         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1393         if (reverse)
1394                 used += used_1;
1395         else if (status) {
1396                 /*
1397                  * Not having reverse hunk is not an error, but having
1398                  * a corrupt reverse hunk is.
1399                  */
1400                 free((void*) forward->patch);
1401                 free(forward);
1402                 return status;
1403         }
1404         forward->next = reverse;
1405         patch->fragments = forward;
1406         patch->is_binary = 1;
1407         return used;
1408 }
1409
1410 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1411 {
1412         int hdrsize, patchsize;
1413         int offset = find_header(buffer, size, &hdrsize, patch);
1414
1415         if (offset < 0)
1416                 return offset;
1417
1418         patch->ws_rule = whitespace_rule(patch->new_name
1419                                          ? patch->new_name
1420                                          : patch->old_name);
1421
1422         patchsize = parse_single_patch(buffer + offset + hdrsize,
1423                                        size - offset - hdrsize, patch);
1424
1425         if (!patchsize) {
1426                 static const char *binhdr[] = {
1427                         "Binary files ",
1428                         "Files ",
1429                         NULL,
1430                 };
1431                 static const char git_binary[] = "GIT binary patch\n";
1432                 int i;
1433                 int hd = hdrsize + offset;
1434                 unsigned long llen = linelen(buffer + hd, size - hd);
1435
1436                 if (llen == sizeof(git_binary) - 1 &&
1437                     !memcmp(git_binary, buffer + hd, llen)) {
1438                         int used;
1439                         linenr++;
1440                         used = parse_binary(buffer + hd + llen,
1441                                             size - hd - llen, patch);
1442                         if (used)
1443                                 patchsize = used + llen;
1444                         else
1445                                 patchsize = 0;
1446                 }
1447                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1448                         for (i = 0; binhdr[i]; i++) {
1449                                 int len = strlen(binhdr[i]);
1450                                 if (len < size - hd &&
1451                                     !memcmp(binhdr[i], buffer + hd, len)) {
1452                                         linenr++;
1453                                         patch->is_binary = 1;
1454                                         patchsize = llen;
1455                                         break;
1456                                 }
1457                         }
1458                 }
1459
1460                 /* Empty patch cannot be applied if it is a text patch
1461                  * without metadata change.  A binary patch appears
1462                  * empty to us here.
1463                  */
1464                 if ((apply || check) &&
1465                     (!patch->is_binary && !metadata_changes(patch)))
1466                         die("patch with only garbage at line %d", linenr);
1467         }
1468
1469         return offset + hdrsize + patchsize;
1470 }
1471
1472 #define swap(a,b) myswap((a),(b),sizeof(a))
1473
1474 #define myswap(a, b, size) do {         \
1475         unsigned char mytmp[size];      \
1476         memcpy(mytmp, &a, size);                \
1477         memcpy(&a, &b, size);           \
1478         memcpy(&b, mytmp, size);                \
1479 } while (0)
1480
1481 static void reverse_patches(struct patch *p)
1482 {
1483         for (; p; p = p->next) {
1484                 struct fragment *frag = p->fragments;
1485
1486                 swap(p->new_name, p->old_name);
1487                 swap(p->new_mode, p->old_mode);
1488                 swap(p->is_new, p->is_delete);
1489                 swap(p->lines_added, p->lines_deleted);
1490                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1491
1492                 for (; frag; frag = frag->next) {
1493                         swap(frag->newpos, frag->oldpos);
1494                         swap(frag->newlines, frag->oldlines);
1495                 }
1496         }
1497 }
1498
1499 static const char pluses[] =
1500 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1501 static const char minuses[]=
1502 "----------------------------------------------------------------------";
1503
1504 static void show_stats(struct patch *patch)
1505 {
1506         struct strbuf qname = STRBUF_INIT;
1507         char *cp = patch->new_name ? patch->new_name : patch->old_name;
1508         int max, add, del;
1509
1510         quote_c_style(cp, &qname, NULL, 0);
1511
1512         /*
1513          * "scale" the filename
1514          */
1515         max = max_len;
1516         if (max > 50)
1517                 max = 50;
1518
1519         if (qname.len > max) {
1520                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
1521                 if (!cp)
1522                         cp = qname.buf + qname.len + 3 - max;
1523                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
1524         }
1525
1526         if (patch->is_binary) {
1527                 printf(" %-*s |  Bin\n", max, qname.buf);
1528                 strbuf_release(&qname);
1529                 return;
1530         }
1531
1532         printf(" %-*s |", max, qname.buf);
1533         strbuf_release(&qname);
1534
1535         /*
1536          * scale the add/delete
1537          */
1538         max = max + max_change > 70 ? 70 - max : max_change;
1539         add = patch->lines_added;
1540         del = patch->lines_deleted;
1541
1542         if (max_change > 0) {
1543                 int total = ((add + del) * max + max_change / 2) / max_change;
1544                 add = (add * max + max_change / 2) / max_change;
1545                 del = total - add;
1546         }
1547         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
1548                 add, pluses, del, minuses);
1549 }
1550
1551 static int read_old_data(struct stat *st, const char *path, struct strbuf *buf)
1552 {
1553         switch (st->st_mode & S_IFMT) {
1554         case S_IFLNK:
1555                 strbuf_grow(buf, st->st_size);
1556                 if (readlink(path, buf->buf, st->st_size) != st->st_size)
1557                         return -1;
1558                 strbuf_setlen(buf, st->st_size);
1559                 return 0;
1560         case S_IFREG:
1561                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
1562                         return error("unable to open or read %s", path);
1563                 convert_to_git(path, buf->buf, buf->len, buf, 0);
1564                 return 0;
1565         default:
1566                 return -1;
1567         }
1568 }
1569
1570 static void update_pre_post_images(struct image *preimage,
1571                                    struct image *postimage,
1572                                    char *buf,
1573                                    size_t len)
1574 {
1575         int i, ctx;
1576         char *new, *old, *fixed;
1577         struct image fixed_preimage;
1578
1579         /*
1580          * Update the preimage with whitespace fixes.  Note that we
1581          * are not losing preimage->buf -- apply_one_fragment() will
1582          * free "oldlines".
1583          */
1584         prepare_image(&fixed_preimage, buf, len, 1);
1585         assert(fixed_preimage.nr == preimage->nr);
1586         for (i = 0; i < preimage->nr; i++)
1587                 fixed_preimage.line[i].flag = preimage->line[i].flag;
1588         free(preimage->line_allocated);
1589         *preimage = fixed_preimage;
1590
1591         /*
1592          * Adjust the common context lines in postimage, in place.
1593          * This is possible because whitespace fixing does not make
1594          * the string grow.
1595          */
1596         new = old = postimage->buf;
1597         fixed = preimage->buf;
1598         for (i = ctx = 0; i < postimage->nr; i++) {
1599                 size_t len = postimage->line[i].len;
1600                 if (!(postimage->line[i].flag & LINE_COMMON)) {
1601                         /* an added line -- no counterparts in preimage */
1602                         memmove(new, old, len);
1603                         old += len;
1604                         new += len;
1605                         continue;
1606                 }
1607
1608                 /* a common context -- skip it in the original postimage */
1609                 old += len;
1610
1611                 /* and find the corresponding one in the fixed preimage */
1612                 while (ctx < preimage->nr &&
1613                        !(preimage->line[ctx].flag & LINE_COMMON)) {
1614                         fixed += preimage->line[ctx].len;
1615                         ctx++;
1616                 }
1617                 if (preimage->nr <= ctx)
1618                         die("oops");
1619
1620                 /* and copy it in, while fixing the line length */
1621                 len = preimage->line[ctx].len;
1622                 memcpy(new, fixed, len);
1623                 new += len;
1624                 fixed += len;
1625                 postimage->line[i].len = len;
1626                 ctx++;
1627         }
1628
1629         /* Fix the length of the whole thing */
1630         postimage->len = new - postimage->buf;
1631 }
1632
1633 static int match_fragment(struct image *img,
1634                           struct image *preimage,
1635                           struct image *postimage,
1636                           unsigned long try,
1637                           int try_lno,
1638                           unsigned ws_rule,
1639                           int match_beginning, int match_end)
1640 {
1641         int i;
1642         char *fixed_buf, *buf, *orig, *target;
1643
1644         if (preimage->nr + try_lno > img->nr)
1645                 return 0;
1646
1647         if (match_beginning && try_lno)
1648                 return 0;
1649
1650         if (match_end && preimage->nr + try_lno != img->nr)
1651                 return 0;
1652
1653         /* Quick hash check */
1654         for (i = 0; i < preimage->nr; i++)
1655                 if (preimage->line[i].hash != img->line[try_lno + i].hash)
1656                         return 0;
1657
1658         /*
1659          * Do we have an exact match?  If we were told to match
1660          * at the end, size must be exactly at try+fragsize,
1661          * otherwise try+fragsize must be still within the preimage,
1662          * and either case, the old piece should match the preimage
1663          * exactly.
1664          */
1665         if ((match_end
1666              ? (try + preimage->len == img->len)
1667              : (try + preimage->len <= img->len)) &&
1668             !memcmp(img->buf + try, preimage->buf, preimage->len))
1669                 return 1;
1670
1671         if (ws_error_action != correct_ws_error)
1672                 return 0;
1673
1674         /*
1675          * The hunk does not apply byte-by-byte, but the hash says
1676          * it might with whitespace fuzz.
1677          */
1678         fixed_buf = xmalloc(preimage->len + 1);
1679         buf = fixed_buf;
1680         orig = preimage->buf;
1681         target = img->buf + try;
1682         for (i = 0; i < preimage->nr; i++) {
1683                 size_t fixlen; /* length after fixing the preimage */
1684                 size_t oldlen = preimage->line[i].len;
1685                 size_t tgtlen = img->line[try_lno + i].len;
1686                 size_t tgtfixlen; /* length after fixing the target line */
1687                 char tgtfixbuf[1024], *tgtfix;
1688                 int match;
1689
1690                 /* Try fixing the line in the preimage */
1691                 fixlen = ws_fix_copy(buf, orig, oldlen, ws_rule, NULL);
1692
1693                 /* Try fixing the line in the target */
1694                 if (sizeof(tgtfixbuf) > tgtlen)
1695                         tgtfix = tgtfixbuf;
1696                 else
1697                         tgtfix = xmalloc(tgtlen);
1698                 tgtfixlen = ws_fix_copy(tgtfix, target, tgtlen, ws_rule, NULL);
1699
1700                 /*
1701                  * If they match, either the preimage was based on
1702                  * a version before our tree fixed whitespace breakage,
1703                  * or we are lacking a whitespace-fix patch the tree
1704                  * the preimage was based on already had (i.e. target
1705                  * has whitespace breakage, the preimage doesn't).
1706                  * In either case, we are fixing the whitespace breakages
1707                  * so we might as well take the fix together with their
1708                  * real change.
1709                  */
1710                 match = (tgtfixlen == fixlen && !memcmp(tgtfix, buf, fixlen));
1711
1712                 if (tgtfix != tgtfixbuf)
1713                         free(tgtfix);
1714                 if (!match)
1715                         goto unmatch_exit;
1716
1717                 orig += oldlen;
1718                 buf += fixlen;
1719                 target += tgtlen;
1720         }
1721
1722         /*
1723          * Yes, the preimage is based on an older version that still
1724          * has whitespace breakages unfixed, and fixing them makes the
1725          * hunk match.  Update the context lines in the postimage.
1726          */
1727         update_pre_post_images(preimage, postimage,
1728                                fixed_buf, buf - fixed_buf);
1729         return 1;
1730
1731  unmatch_exit:
1732         free(fixed_buf);
1733         return 0;
1734 }
1735
1736 static int find_pos(struct image *img,
1737                     struct image *preimage,
1738                     struct image *postimage,
1739                     int line,
1740                     unsigned ws_rule,
1741                     int match_beginning, int match_end)
1742 {
1743         int i;
1744         unsigned long backwards, forwards, try;
1745         int backwards_lno, forwards_lno, try_lno;
1746
1747         if (preimage->nr > img->nr)
1748                 return -1;
1749
1750         /*
1751          * If match_begining or match_end is specified, there is no
1752          * point starting from a wrong line that will never match and
1753          * wander around and wait for a match at the specified end.
1754          */
1755         if (match_beginning)
1756                 line = 0;
1757         else if (match_end)
1758                 line = img->nr - preimage->nr;
1759
1760         if (line > img->nr)
1761                 line = img->nr;
1762
1763         try = 0;
1764         for (i = 0; i < line; i++)
1765                 try += img->line[i].len;
1766
1767         /*
1768          * There's probably some smart way to do this, but I'll leave
1769          * that to the smart and beautiful people. I'm simple and stupid.
1770          */
1771         backwards = try;
1772         backwards_lno = line;
1773         forwards = try;
1774         forwards_lno = line;
1775         try_lno = line;
1776
1777         for (i = 0; ; i++) {
1778                 if (match_fragment(img, preimage, postimage,
1779                                    try, try_lno, ws_rule,
1780                                    match_beginning, match_end))
1781                         return try_lno;
1782
1783         again:
1784                 if (backwards_lno == 0 && forwards_lno == img->nr)
1785                         break;
1786
1787                 if (i & 1) {
1788                         if (backwards_lno == 0) {
1789                                 i++;
1790                                 goto again;
1791                         }
1792                         backwards_lno--;
1793                         backwards -= img->line[backwards_lno].len;
1794                         try = backwards;
1795                         try_lno = backwards_lno;
1796                 } else {
1797                         if (forwards_lno == img->nr) {
1798                                 i++;
1799                                 goto again;
1800                         }
1801                         forwards += img->line[forwards_lno].len;
1802                         forwards_lno++;
1803                         try = forwards;
1804                         try_lno = forwards_lno;
1805                 }
1806
1807         }
1808         return -1;
1809 }
1810
1811 static void remove_first_line(struct image *img)
1812 {
1813         img->buf += img->line[0].len;
1814         img->len -= img->line[0].len;
1815         img->line++;
1816         img->nr--;
1817 }
1818
1819 static void remove_last_line(struct image *img)
1820 {
1821         img->len -= img->line[--img->nr].len;
1822 }
1823
1824 static void update_image(struct image *img,
1825                          int applied_pos,
1826                          struct image *preimage,
1827                          struct image *postimage)
1828 {
1829         /*
1830          * remove the copy of preimage at offset in img
1831          * and replace it with postimage
1832          */
1833         int i, nr;
1834         size_t remove_count, insert_count, applied_at = 0;
1835         char *result;
1836
1837         for (i = 0; i < applied_pos; i++)
1838                 applied_at += img->line[i].len;
1839
1840         remove_count = 0;
1841         for (i = 0; i < preimage->nr; i++)
1842                 remove_count += img->line[applied_pos + i].len;
1843         insert_count = postimage->len;
1844
1845         /* Adjust the contents */
1846         result = xmalloc(img->len + insert_count - remove_count + 1);
1847         memcpy(result, img->buf, applied_at);
1848         memcpy(result + applied_at, postimage->buf, postimage->len);
1849         memcpy(result + applied_at + postimage->len,
1850                img->buf + (applied_at + remove_count),
1851                img->len - (applied_at + remove_count));
1852         free(img->buf);
1853         img->buf = result;
1854         img->len += insert_count - remove_count;
1855         result[img->len] = '\0';
1856
1857         /* Adjust the line table */
1858         nr = img->nr + postimage->nr - preimage->nr;
1859         if (preimage->nr < postimage->nr) {
1860                 /*
1861                  * NOTE: this knows that we never call remove_first_line()
1862                  * on anything other than pre/post image.
1863                  */
1864                 img->line = xrealloc(img->line, nr * sizeof(*img->line));
1865                 img->line_allocated = img->line;
1866         }
1867         if (preimage->nr != postimage->nr)
1868                 memmove(img->line + applied_pos + postimage->nr,
1869                         img->line + applied_pos + preimage->nr,
1870                         (img->nr - (applied_pos + preimage->nr)) *
1871                         sizeof(*img->line));
1872         memcpy(img->line + applied_pos,
1873                postimage->line,
1874                postimage->nr * sizeof(*img->line));
1875         img->nr = nr;
1876 }
1877
1878 static int apply_one_fragment(struct image *img, struct fragment *frag,
1879                               int inaccurate_eof, unsigned ws_rule)
1880 {
1881         int match_beginning, match_end;
1882         const char *patch = frag->patch;
1883         int size = frag->size;
1884         char *old, *new, *oldlines, *newlines;
1885         int new_blank_lines_at_end = 0;
1886         unsigned long leading, trailing;
1887         int pos, applied_pos;
1888         struct image preimage;
1889         struct image postimage;
1890
1891         memset(&preimage, 0, sizeof(preimage));
1892         memset(&postimage, 0, sizeof(postimage));
1893         oldlines = xmalloc(size);
1894         newlines = xmalloc(size);
1895
1896         old = oldlines;
1897         new = newlines;
1898         while (size > 0) {
1899                 char first;
1900                 int len = linelen(patch, size);
1901                 int plen, added;
1902                 int added_blank_line = 0;
1903
1904                 if (!len)
1905                         break;
1906
1907                 /*
1908                  * "plen" is how much of the line we should use for
1909                  * the actual patch data. Normally we just remove the
1910                  * first character on the line, but if the line is
1911                  * followed by "\ No newline", then we also remove the
1912                  * last one (which is the newline, of course).
1913                  */
1914                 plen = len - 1;
1915                 if (len < size && patch[len] == '\\')
1916                         plen--;
1917                 first = *patch;
1918                 if (apply_in_reverse) {
1919                         if (first == '-')
1920                                 first = '+';
1921                         else if (first == '+')
1922                                 first = '-';
1923                 }
1924
1925                 switch (first) {
1926                 case '\n':
1927                         /* Newer GNU diff, empty context line */
1928                         if (plen < 0)
1929                                 /* ... followed by '\No newline'; nothing */
1930                                 break;
1931                         *old++ = '\n';
1932                         *new++ = '\n';
1933                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
1934                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
1935                         break;
1936                 case ' ':
1937                 case '-':
1938                         memcpy(old, patch + 1, plen);
1939                         add_line_info(&preimage, old, plen,
1940                                       (first == ' ' ? LINE_COMMON : 0));
1941                         old += plen;
1942                         if (first == '-')
1943                                 break;
1944                 /* Fall-through for ' ' */
1945                 case '+':
1946                         /* --no-add does not add new lines */
1947                         if (first == '+' && no_add)
1948                                 break;
1949
1950                         if (first != '+' ||
1951                             !whitespace_error ||
1952                             ws_error_action != correct_ws_error) {
1953                                 memcpy(new, patch + 1, plen);
1954                                 added = plen;
1955                         }
1956                         else {
1957                                 added = ws_fix_copy(new, patch + 1, plen, ws_rule, &applied_after_fixing_ws);
1958                         }
1959                         add_line_info(&postimage, new, added,
1960                                       (first == '+' ? 0 : LINE_COMMON));
1961                         new += added;
1962                         if (first == '+' &&
1963                             added == 1 && new[-1] == '\n')
1964                                 added_blank_line = 1;
1965                         break;
1966                 case '@': case '\\':
1967                         /* Ignore it, we already handled it */
1968                         break;
1969                 default:
1970                         if (apply_verbosely)
1971                                 error("invalid start of line: '%c'", first);
1972                         return -1;
1973                 }
1974                 if (added_blank_line)
1975                         new_blank_lines_at_end++;
1976                 else
1977                         new_blank_lines_at_end = 0;
1978                 patch += len;
1979                 size -= len;
1980         }
1981         if (inaccurate_eof &&
1982             old > oldlines && old[-1] == '\n' &&
1983             new > newlines && new[-1] == '\n') {
1984                 old--;
1985                 new--;
1986         }
1987
1988         leading = frag->leading;
1989         trailing = frag->trailing;
1990
1991         /*
1992          * A hunk to change lines at the beginning would begin with
1993          * @@ -1,L +N,M @@
1994          * but we need to be careful.  -U0 that inserts before the second
1995          * line also has this pattern.
1996          *
1997          * And a hunk to add to an empty file would begin with
1998          * @@ -0,0 +N,M @@
1999          *
2000          * In other words, a hunk that is (frag->oldpos <= 1) with or
2001          * without leading context must match at the beginning.
2002          */
2003         match_beginning = (!frag->oldpos ||
2004                            (frag->oldpos == 1 && !unidiff_zero));
2005
2006         /*
2007          * A hunk without trailing lines must match at the end.
2008          * However, we simply cannot tell if a hunk must match end
2009          * from the lack of trailing lines if the patch was generated
2010          * with unidiff without any context.
2011          */
2012         match_end = !unidiff_zero && !trailing;
2013
2014         pos = frag->newpos ? (frag->newpos - 1) : 0;
2015         preimage.buf = oldlines;
2016         preimage.len = old - oldlines;
2017         postimage.buf = newlines;
2018         postimage.len = new - newlines;
2019         preimage.line = preimage.line_allocated;
2020         postimage.line = postimage.line_allocated;
2021
2022         for (;;) {
2023
2024                 applied_pos = find_pos(img, &preimage, &postimage, pos,
2025                                        ws_rule, match_beginning, match_end);
2026
2027                 if (applied_pos >= 0)
2028                         break;
2029
2030                 /* Am I at my context limits? */
2031                 if ((leading <= p_context) && (trailing <= p_context))
2032                         break;
2033                 if (match_beginning || match_end) {
2034                         match_beginning = match_end = 0;
2035                         continue;
2036                 }
2037
2038                 /*
2039                  * Reduce the number of context lines; reduce both
2040                  * leading and trailing if they are equal otherwise
2041                  * just reduce the larger context.
2042                  */
2043                 if (leading >= trailing) {
2044                         remove_first_line(&preimage);
2045                         remove_first_line(&postimage);
2046                         pos--;
2047                         leading--;
2048                 }
2049                 if (trailing > leading) {
2050                         remove_last_line(&preimage);
2051                         remove_last_line(&postimage);
2052                         trailing--;
2053                 }
2054         }
2055
2056         if (applied_pos >= 0) {
2057                 if (ws_error_action == correct_ws_error &&
2058                     new_blank_lines_at_end &&
2059                     postimage.nr + applied_pos == img->nr) {
2060                         /*
2061                          * If the patch application adds blank lines
2062                          * at the end, and if the patch applies at the
2063                          * end of the image, remove those added blank
2064                          * lines.
2065                          */
2066                         while (new_blank_lines_at_end--)
2067                                 remove_last_line(&postimage);
2068                 }
2069
2070                 /*
2071                  * Warn if it was necessary to reduce the number
2072                  * of context lines.
2073                  */
2074                 if ((leading != frag->leading) ||
2075                     (trailing != frag->trailing))
2076                         fprintf(stderr, "Context reduced to (%ld/%ld)"
2077                                 " to apply fragment at %d\n",
2078                                 leading, trailing, applied_pos+1);
2079                 update_image(img, applied_pos, &preimage, &postimage);
2080         } else {
2081                 if (apply_verbosely)
2082                         error("while searching for:\n%.*s",
2083                               (int)(old - oldlines), oldlines);
2084         }
2085
2086         free(oldlines);
2087         free(newlines);
2088         free(preimage.line_allocated);
2089         free(postimage.line_allocated);
2090
2091         return (applied_pos < 0);
2092 }
2093
2094 static int apply_binary_fragment(struct image *img, struct patch *patch)
2095 {
2096         struct fragment *fragment = patch->fragments;
2097         unsigned long len;
2098         void *dst;
2099
2100         /* Binary patch is irreversible without the optional second hunk */
2101         if (apply_in_reverse) {
2102                 if (!fragment->next)
2103                         return error("cannot reverse-apply a binary patch "
2104                                      "without the reverse hunk to '%s'",
2105                                      patch->new_name
2106                                      ? patch->new_name : patch->old_name);
2107                 fragment = fragment->next;
2108         }
2109         switch (fragment->binary_patch_method) {
2110         case BINARY_DELTA_DEFLATED:
2111                 dst = patch_delta(img->buf, img->len, fragment->patch,
2112                                   fragment->size, &len);
2113                 if (!dst)
2114                         return -1;
2115                 clear_image(img);
2116                 img->buf = dst;
2117                 img->len = len;
2118                 return 0;
2119         case BINARY_LITERAL_DEFLATED:
2120                 clear_image(img);
2121                 img->len = fragment->size;
2122                 img->buf = xmalloc(img->len+1);
2123                 memcpy(img->buf, fragment->patch, img->len);
2124                 img->buf[img->len] = '\0';
2125                 return 0;
2126         }
2127         return -1;
2128 }
2129
2130 static int apply_binary(struct image *img, struct patch *patch)
2131 {
2132         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2133         unsigned char sha1[20];
2134
2135         /*
2136          * For safety, we require patch index line to contain
2137          * full 40-byte textual SHA1 for old and new, at least for now.
2138          */
2139         if (strlen(patch->old_sha1_prefix) != 40 ||
2140             strlen(patch->new_sha1_prefix) != 40 ||
2141             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
2142             get_sha1_hex(patch->new_sha1_prefix, sha1))
2143                 return error("cannot apply binary patch to '%s' "
2144                              "without full index line", name);
2145
2146         if (patch->old_name) {
2147                 /*
2148                  * See if the old one matches what the patch
2149                  * applies to.
2150                  */
2151                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2152                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
2153                         return error("the patch applies to '%s' (%s), "
2154                                      "which does not match the "
2155                                      "current contents.",
2156                                      name, sha1_to_hex(sha1));
2157         }
2158         else {
2159                 /* Otherwise, the old one must be empty. */
2160                 if (img->len)
2161                         return error("the patch applies to an empty "
2162                                      "'%s' but it is not empty", name);
2163         }
2164
2165         get_sha1_hex(patch->new_sha1_prefix, sha1);
2166         if (is_null_sha1(sha1)) {
2167                 clear_image(img);
2168                 return 0; /* deletion patch */
2169         }
2170
2171         if (has_sha1_file(sha1)) {
2172                 /* We already have the postimage */
2173                 enum object_type type;
2174                 unsigned long size;
2175                 char *result;
2176
2177                 result = read_sha1_file(sha1, &type, &size);
2178                 if (!result)
2179                         return error("the necessary postimage %s for "
2180                                      "'%s' cannot be read",
2181                                      patch->new_sha1_prefix, name);
2182                 clear_image(img);
2183                 img->buf = result;
2184                 img->len = size;
2185         } else {
2186                 /*
2187                  * We have verified buf matches the preimage;
2188                  * apply the patch data to it, which is stored
2189                  * in the patch->fragments->{patch,size}.
2190                  */
2191                 if (apply_binary_fragment(img, patch))
2192                         return error("binary patch does not apply to '%s'",
2193                                      name);
2194
2195                 /* verify that the result matches */
2196                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2197                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
2198                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)",
2199                                 name, patch->new_sha1_prefix, sha1_to_hex(sha1));
2200         }
2201
2202         return 0;
2203 }
2204
2205 static int apply_fragments(struct image *img, struct patch *patch)
2206 {
2207         struct fragment *frag = patch->fragments;
2208         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2209         unsigned ws_rule = patch->ws_rule;
2210         unsigned inaccurate_eof = patch->inaccurate_eof;
2211
2212         if (patch->is_binary)
2213                 return apply_binary(img, patch);
2214
2215         while (frag) {
2216                 if (apply_one_fragment(img, frag, inaccurate_eof, ws_rule)) {
2217                         error("patch failed: %s:%ld", name, frag->oldpos);
2218                         if (!apply_with_reject)
2219                                 return -1;
2220                         frag->rejected = 1;
2221                 }
2222                 frag = frag->next;
2223         }
2224         return 0;
2225 }
2226
2227 static int read_file_or_gitlink(struct cache_entry *ce, struct strbuf *buf)
2228 {
2229         if (!ce)
2230                 return 0;
2231
2232         if (S_ISGITLINK(ce->ce_mode)) {
2233                 strbuf_grow(buf, 100);
2234                 strbuf_addf(buf, "Subproject commit %s\n", sha1_to_hex(ce->sha1));
2235         } else {
2236                 enum object_type type;
2237                 unsigned long sz;
2238                 char *result;
2239
2240                 result = read_sha1_file(ce->sha1, &type, &sz);
2241                 if (!result)
2242                         return -1;
2243                 /* XXX read_sha1_file NUL-terminates */
2244                 strbuf_attach(buf, result, sz, sz + 1);
2245         }
2246         return 0;
2247 }
2248
2249 static struct patch *in_fn_table(const char *name)
2250 {
2251         struct string_list_item *item;
2252
2253         if (name == NULL)
2254                 return NULL;
2255
2256         item = string_list_lookup(name, &fn_table);
2257         if (item != NULL)
2258                 return (struct patch *)item->util;
2259
2260         return NULL;
2261 }
2262
2263 static void add_to_fn_table(struct patch *patch)
2264 {
2265         struct string_list_item *item;
2266
2267         /*
2268          * Always add new_name unless patch is a deletion
2269          * This should cover the cases for normal diffs,
2270          * file creations and copies
2271          */
2272         if (patch->new_name != NULL) {
2273                 item = string_list_insert(patch->new_name, &fn_table);
2274                 item->util = patch;
2275         }
2276
2277         /*
2278          * store a failure on rename/deletion cases because
2279          * later chunks shouldn't patch old names
2280          */
2281         if ((patch->new_name == NULL) || (patch->is_rename)) {
2282                 item = string_list_insert(patch->old_name, &fn_table);
2283                 item->util = (struct patch *) -1;
2284         }
2285 }
2286
2287 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
2288 {
2289         struct strbuf buf = STRBUF_INIT;
2290         struct image image;
2291         size_t len;
2292         char *img;
2293         struct patch *tpatch;
2294
2295         if (!(patch->is_copy || patch->is_rename) &&
2296             ((tpatch = in_fn_table(patch->old_name)) != NULL)) {
2297                 if (tpatch == (struct patch *) -1) {
2298                         return error("patch %s has been renamed/deleted",
2299                                 patch->old_name);
2300                 }
2301                 /* We have a patched copy in memory use that */
2302                 strbuf_add(&buf, tpatch->result, tpatch->resultsize);
2303         } else if (cached) {
2304                 if (read_file_or_gitlink(ce, &buf))
2305                         return error("read of %s failed", patch->old_name);
2306         } else if (patch->old_name) {
2307                 if (S_ISGITLINK(patch->old_mode)) {
2308                         if (ce) {
2309                                 read_file_or_gitlink(ce, &buf);
2310                         } else {
2311                                 /*
2312                                  * There is no way to apply subproject
2313                                  * patch without looking at the index.
2314                                  */
2315                                 patch->fragments = NULL;
2316                         }
2317                 } else {
2318                         if (read_old_data(st, patch->old_name, &buf))
2319                                 return error("read of %s failed", patch->old_name);
2320                 }
2321         }
2322
2323         img = strbuf_detach(&buf, &len);
2324         prepare_image(&image, img, len, !patch->is_binary);
2325
2326         if (apply_fragments(&image, patch) < 0)
2327                 return -1; /* note with --reject this succeeds. */
2328         patch->result = image.buf;
2329         patch->resultsize = image.len;
2330         add_to_fn_table(patch);
2331         free(image.line_allocated);
2332
2333         if (0 < patch->is_delete && patch->resultsize)
2334                 return error("removal patch leaves file contents");
2335
2336         return 0;
2337 }
2338
2339 static int check_to_create_blob(const char *new_name, int ok_if_exists)
2340 {
2341         struct stat nst;
2342         if (!lstat(new_name, &nst)) {
2343                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2344                         return 0;
2345                 /*
2346                  * A leading component of new_name might be a symlink
2347                  * that is going to be removed with this patch, but
2348                  * still pointing at somewhere that has the path.
2349                  * In such a case, path "new_name" does not exist as
2350                  * far as git is concerned.
2351                  */
2352                 if (has_symlink_leading_path(strlen(new_name), new_name))
2353                         return 0;
2354
2355                 return error("%s: already exists in working directory", new_name);
2356         }
2357         else if ((errno != ENOENT) && (errno != ENOTDIR))
2358                 return error("%s: %s", new_name, strerror(errno));
2359         return 0;
2360 }
2361
2362 static int verify_index_match(struct cache_entry *ce, struct stat *st)
2363 {
2364         if (S_ISGITLINK(ce->ce_mode)) {
2365                 if (!S_ISDIR(st->st_mode))
2366                         return -1;
2367                 return 0;
2368         }
2369         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID);
2370 }
2371
2372 static int check_preimage(struct patch *patch, struct cache_entry **ce, struct stat *st)
2373 {
2374         const char *old_name = patch->old_name;
2375         struct patch *tpatch = NULL;
2376         int stat_ret = 0;
2377         unsigned st_mode = 0;
2378
2379         /*
2380          * Make sure that we do not have local modifications from the
2381          * index when we are looking at the index.  Also make sure
2382          * we have the preimage file to be patched in the work tree,
2383          * unless --cached, which tells git to apply only in the index.
2384          */
2385         if (!old_name)
2386                 return 0;
2387
2388         assert(patch->is_new <= 0);
2389
2390         if (!(patch->is_copy || patch->is_rename) &&
2391             (tpatch = in_fn_table(old_name)) != NULL) {
2392                 if (tpatch == (struct patch *) -1) {
2393                         return error("%s: has been deleted/renamed", old_name);
2394                 }
2395                 st_mode = tpatch->new_mode;
2396         } else if (!cached) {
2397                 stat_ret = lstat(old_name, st);
2398                 if (stat_ret && errno != ENOENT)
2399                         return error("%s: %s", old_name, strerror(errno));
2400         }
2401
2402         if (check_index && !tpatch) {
2403                 int pos = cache_name_pos(old_name, strlen(old_name));
2404                 if (pos < 0) {
2405                         if (patch->is_new < 0)
2406                                 goto is_new;
2407                         return error("%s: does not exist in index", old_name);
2408                 }
2409                 *ce = active_cache[pos];
2410                 if (stat_ret < 0) {
2411                         struct checkout costate;
2412                         /* checkout */
2413                         costate.base_dir = "";
2414                         costate.base_dir_len = 0;
2415                         costate.force = 0;
2416                         costate.quiet = 0;
2417                         costate.not_new = 0;
2418                         costate.refresh_cache = 1;
2419                         if (checkout_entry(*ce, &costate, NULL) ||
2420                             lstat(old_name, st))
2421                                 return -1;
2422                 }
2423                 if (!cached && verify_index_match(*ce, st))
2424                         return error("%s: does not match index", old_name);
2425                 if (cached)
2426                         st_mode = (*ce)->ce_mode;
2427         } else if (stat_ret < 0) {
2428                 if (patch->is_new < 0)
2429                         goto is_new;
2430                 return error("%s: %s", old_name, strerror(errno));
2431         }
2432
2433         if (!cached)
2434                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
2435
2436         if (patch->is_new < 0)
2437                 patch->is_new = 0;
2438         if (!patch->old_mode)
2439                 patch->old_mode = st_mode;
2440         if ((st_mode ^ patch->old_mode) & S_IFMT)
2441                 return error("%s: wrong type", old_name);
2442         if (st_mode != patch->old_mode)
2443                 fprintf(stderr, "warning: %s has type %o, expected %o\n",
2444                         old_name, st_mode, patch->old_mode);
2445         return 0;
2446
2447  is_new:
2448         patch->is_new = 1;
2449         patch->is_delete = 0;
2450         patch->old_name = NULL;
2451         return 0;
2452 }
2453
2454 static int check_patch(struct patch *patch)
2455 {
2456         struct stat st;
2457         const char *old_name = patch->old_name;
2458         const char *new_name = patch->new_name;
2459         const char *name = old_name ? old_name : new_name;
2460         struct cache_entry *ce = NULL;
2461         int ok_if_exists;
2462         int status;
2463
2464         patch->rejected = 1; /* we will drop this after we succeed */
2465
2466         status = check_preimage(patch, &ce, &st);
2467         if (status)
2468                 return status;
2469         old_name = patch->old_name;
2470
2471         if (in_fn_table(new_name) == (struct patch *) -1)
2472                 /*
2473                  * A type-change diff is always split into a patch to
2474                  * delete old, immediately followed by a patch to
2475                  * create new (see diff.c::run_diff()); in such a case
2476                  * it is Ok that the entry to be deleted by the
2477                  * previous patch is still in the working tree and in
2478                  * the index.
2479                  */
2480                 ok_if_exists = 1;
2481         else
2482                 ok_if_exists = 0;
2483
2484         if (new_name &&
2485             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2486                 if (check_index &&
2487                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2488                     !ok_if_exists)
2489                         return error("%s: already exists in index", new_name);
2490                 if (!cached) {
2491                         int err = check_to_create_blob(new_name, ok_if_exists);
2492                         if (err)
2493                                 return err;
2494                 }
2495                 if (!patch->new_mode) {
2496                         if (0 < patch->is_new)
2497                                 patch->new_mode = S_IFREG | 0644;
2498                         else
2499                                 patch->new_mode = patch->old_mode;
2500                 }
2501         }
2502
2503         if (new_name && old_name) {
2504                 int same = !strcmp(old_name, new_name);
2505                 if (!patch->new_mode)
2506                         patch->new_mode = patch->old_mode;
2507                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2508                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2509                                 patch->new_mode, new_name, patch->old_mode,
2510                                 same ? "" : " of ", same ? "" : old_name);
2511         }
2512
2513         if (apply_data(patch, &st, ce) < 0)
2514                 return error("%s: patch does not apply", name);
2515         patch->rejected = 0;
2516         return 0;
2517 }
2518
2519 static int check_patch_list(struct patch *patch)
2520 {
2521         int err = 0;
2522
2523         while (patch) {
2524                 if (apply_verbosely)
2525                         say_patch_name(stderr,
2526                                        "Checking patch ", patch, "...\n");
2527                 err |= check_patch(patch);
2528                 patch = patch->next;
2529         }
2530         return err;
2531 }
2532
2533 /* This function tries to read the sha1 from the current index */
2534 static int get_current_sha1(const char *path, unsigned char *sha1)
2535 {
2536         int pos;
2537
2538         if (read_cache() < 0)
2539                 return -1;
2540         pos = cache_name_pos(path, strlen(path));
2541         if (pos < 0)
2542                 return -1;
2543         hashcpy(sha1, active_cache[pos]->sha1);
2544         return 0;
2545 }
2546
2547 /* Build an index that contains the just the files needed for a 3way merge */
2548 static void build_fake_ancestor(struct patch *list, const char *filename)
2549 {
2550         struct patch *patch;
2551         struct index_state result = { 0 };
2552         int fd;
2553
2554         /* Once we start supporting the reverse patch, it may be
2555          * worth showing the new sha1 prefix, but until then...
2556          */
2557         for (patch = list; patch; patch = patch->next) {
2558                 const unsigned char *sha1_ptr;
2559                 unsigned char sha1[20];
2560                 struct cache_entry *ce;
2561                 const char *name;
2562
2563                 name = patch->old_name ? patch->old_name : patch->new_name;
2564                 if (0 < patch->is_new)
2565                         continue;
2566                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2567                         /* git diff has no index line for mode/type changes */
2568                         if (!patch->lines_added && !patch->lines_deleted) {
2569                                 if (get_current_sha1(patch->new_name, sha1) ||
2570                                     get_current_sha1(patch->old_name, sha1))
2571                                         die("mode change for %s, which is not "
2572                                                 "in current HEAD", name);
2573                                 sha1_ptr = sha1;
2574                         } else
2575                                 die("sha1 information is lacking or useless "
2576                                         "(%s).", name);
2577                 else
2578                         sha1_ptr = sha1;
2579
2580                 ce = make_cache_entry(patch->old_mode, sha1_ptr, name, 0, 0);
2581                 if (!ce)
2582                         die("make_cache_entry failed for path '%s'", name);
2583                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD))
2584                         die ("Could not add %s to temporary index", name);
2585         }
2586
2587         fd = open(filename, O_WRONLY | O_CREAT, 0666);
2588         if (fd < 0 || write_index(&result, fd) || close(fd))
2589                 die ("Could not write temporary index to %s", filename);
2590
2591         discard_index(&result);
2592 }
2593
2594 static void stat_patch_list(struct patch *patch)
2595 {
2596         int files, adds, dels;
2597
2598         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2599                 files++;
2600                 adds += patch->lines_added;
2601                 dels += patch->lines_deleted;
2602                 show_stats(patch);
2603         }
2604
2605         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2606 }
2607
2608 static void numstat_patch_list(struct patch *patch)
2609 {
2610         for ( ; patch; patch = patch->next) {
2611                 const char *name;
2612                 name = patch->new_name ? patch->new_name : patch->old_name;
2613                 if (patch->is_binary)
2614                         printf("-\t-\t");
2615                 else
2616                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
2617                 write_name_quoted(name, stdout, line_termination);
2618         }
2619 }
2620
2621 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2622 {
2623         if (mode)
2624                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2625         else
2626                 printf(" %s %s\n", newdelete, name);
2627 }
2628
2629 static void show_mode_change(struct patch *p, int show_name)
2630 {
2631         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2632                 if (show_name)
2633                         printf(" mode change %06o => %06o %s\n",
2634                                p->old_mode, p->new_mode, p->new_name);
2635                 else
2636                         printf(" mode change %06o => %06o\n",
2637                                p->old_mode, p->new_mode);
2638         }
2639 }
2640
2641 static void show_rename_copy(struct patch *p)
2642 {
2643         const char *renamecopy = p->is_rename ? "rename" : "copy";
2644         const char *old, *new;
2645
2646         /* Find common prefix */
2647         old = p->old_name;
2648         new = p->new_name;
2649         while (1) {
2650                 const char *slash_old, *slash_new;
2651                 slash_old = strchr(old, '/');
2652                 slash_new = strchr(new, '/');
2653                 if (!slash_old ||
2654                     !slash_new ||
2655                     slash_old - old != slash_new - new ||
2656                     memcmp(old, new, slash_new - new))
2657                         break;
2658                 old = slash_old + 1;
2659                 new = slash_new + 1;
2660         }
2661         /* p->old_name thru old is the common prefix, and old and new
2662          * through the end of names are renames
2663          */
2664         if (old != p->old_name)
2665                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2666                        (int)(old - p->old_name), p->old_name,
2667                        old, new, p->score);
2668         else
2669                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2670                        p->old_name, p->new_name, p->score);
2671         show_mode_change(p, 0);
2672 }
2673
2674 static void summary_patch_list(struct patch *patch)
2675 {
2676         struct patch *p;
2677
2678         for (p = patch; p; p = p->next) {
2679                 if (p->is_new)
2680                         show_file_mode_name("create", p->new_mode, p->new_name);
2681                 else if (p->is_delete)
2682                         show_file_mode_name("delete", p->old_mode, p->old_name);
2683                 else {
2684                         if (p->is_rename || p->is_copy)
2685                                 show_rename_copy(p);
2686                         else {
2687                                 if (p->score) {
2688                                         printf(" rewrite %s (%d%%)\n",
2689                                                p->new_name, p->score);
2690                                         show_mode_change(p, 0);
2691                                 }
2692                                 else
2693                                         show_mode_change(p, 1);
2694                         }
2695                 }
2696         }
2697 }
2698
2699 static void patch_stats(struct patch *patch)
2700 {
2701         int lines = patch->lines_added + patch->lines_deleted;
2702
2703         if (lines > max_change)
2704                 max_change = lines;
2705         if (patch->old_name) {
2706                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2707                 if (!len)
2708                         len = strlen(patch->old_name);
2709                 if (len > max_len)
2710                         max_len = len;
2711         }
2712         if (patch->new_name) {
2713                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2714                 if (!len)
2715                         len = strlen(patch->new_name);
2716                 if (len > max_len)
2717                         max_len = len;
2718         }
2719 }
2720
2721 static void remove_file(struct patch *patch, int rmdir_empty)
2722 {
2723         if (update_index) {
2724                 if (remove_file_from_cache(patch->old_name) < 0)
2725                         die("unable to remove %s from index", patch->old_name);
2726         }
2727         if (!cached) {
2728                 if (S_ISGITLINK(patch->old_mode)) {
2729                         if (rmdir(patch->old_name))
2730                                 warning("unable to remove submodule %s",
2731                                         patch->old_name);
2732                 } else if (!unlink(patch->old_name) && rmdir_empty) {
2733                         remove_path(patch->old_name);
2734                 }
2735         }
2736 }
2737
2738 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2739 {
2740         struct stat st;
2741         struct cache_entry *ce;
2742         int namelen = strlen(path);
2743         unsigned ce_size = cache_entry_size(namelen);
2744
2745         if (!update_index)
2746                 return;
2747
2748         ce = xcalloc(1, ce_size);
2749         memcpy(ce->name, path, namelen);
2750         ce->ce_mode = create_ce_mode(mode);
2751         ce->ce_flags = namelen;
2752         if (S_ISGITLINK(mode)) {
2753                 const char *s = buf;
2754
2755                 if (get_sha1_hex(s + strlen("Subproject commit "), ce->sha1))
2756                         die("corrupt patch for subproject %s", path);
2757         } else {
2758                 if (!cached) {
2759                         if (lstat(path, &st) < 0)
2760                                 die("unable to stat newly created file %s",
2761                                     path);
2762                         fill_stat_cache_info(ce, &st);
2763                 }
2764                 if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2765                         die("unable to create backing store for newly created file %s", path);
2766         }
2767         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2768                 die("unable to add cache entry for %s", path);
2769 }
2770
2771 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2772 {
2773         int fd;
2774         struct strbuf nbuf = STRBUF_INIT;
2775
2776         if (S_ISGITLINK(mode)) {
2777                 struct stat st;
2778                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
2779                         return 0;
2780                 return mkdir(path, 0777);
2781         }
2782
2783         if (has_symlinks && S_ISLNK(mode))
2784                 /* Although buf:size is counted string, it also is NUL
2785                  * terminated.
2786                  */
2787                 return symlink(buf, path);
2788
2789         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2790         if (fd < 0)
2791                 return -1;
2792
2793         if (convert_to_working_tree(path, buf, size, &nbuf)) {
2794                 size = nbuf.len;
2795                 buf  = nbuf.buf;
2796         }
2797         write_or_die(fd, buf, size);
2798         strbuf_release(&nbuf);
2799
2800         if (close(fd) < 0)
2801                 die("closing file %s: %s", path, strerror(errno));
2802         return 0;
2803 }
2804
2805 /*
2806  * We optimistically assume that the directories exist,
2807  * which is true 99% of the time anyway. If they don't,
2808  * we create them and try again.
2809  */
2810 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2811 {
2812         if (cached)
2813                 return;
2814         if (!try_create_file(path, mode, buf, size))
2815                 return;
2816
2817         if (errno == ENOENT) {
2818                 if (safe_create_leading_directories(path))
2819                         return;
2820                 if (!try_create_file(path, mode, buf, size))
2821                         return;
2822         }
2823
2824         if (errno == EEXIST || errno == EACCES) {
2825                 /* We may be trying to create a file where a directory
2826                  * used to be.
2827                  */
2828                 struct stat st;
2829                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
2830                         errno = EEXIST;
2831         }
2832
2833         if (errno == EEXIST) {
2834                 unsigned int nr = getpid();
2835
2836                 for (;;) {
2837                         const char *newpath;
2838                         newpath = mkpath("%s~%u", path, nr);
2839                         if (!try_create_file(newpath, mode, buf, size)) {
2840                                 if (!rename(newpath, path))
2841                                         return;
2842                                 unlink(newpath);
2843                                 break;
2844                         }
2845                         if (errno != EEXIST)
2846                                 break;
2847                         ++nr;
2848                 }
2849         }
2850         die("unable to write file %s mode %o", path, mode);
2851 }
2852
2853 static void create_file(struct patch *patch)
2854 {
2855         char *path = patch->new_name;
2856         unsigned mode = patch->new_mode;
2857         unsigned long size = patch->resultsize;
2858         char *buf = patch->result;
2859
2860         if (!mode)
2861                 mode = S_IFREG | 0644;
2862         create_one_file(path, mode, buf, size);
2863         add_index_file(path, mode, buf, size);
2864 }
2865
2866 /* phase zero is to remove, phase one is to create */
2867 static void write_out_one_result(struct patch *patch, int phase)
2868 {
2869         if (patch->is_delete > 0) {
2870                 if (phase == 0)
2871                         remove_file(patch, 1);
2872                 return;
2873         }
2874         if (patch->is_new > 0 || patch->is_copy) {
2875                 if (phase == 1)
2876                         create_file(patch);
2877                 return;
2878         }
2879         /*
2880          * Rename or modification boils down to the same
2881          * thing: remove the old, write the new
2882          */
2883         if (phase == 0)
2884                 remove_file(patch, patch->is_rename);
2885         if (phase == 1)
2886                 create_file(patch);
2887 }
2888
2889 static int write_out_one_reject(struct patch *patch)
2890 {
2891         FILE *rej;
2892         char namebuf[PATH_MAX];
2893         struct fragment *frag;
2894         int cnt = 0;
2895
2896         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2897                 if (!frag->rejected)
2898                         continue;
2899                 cnt++;
2900         }
2901
2902         if (!cnt) {
2903                 if (apply_verbosely)
2904                         say_patch_name(stderr,
2905                                        "Applied patch ", patch, " cleanly.\n");
2906                 return 0;
2907         }
2908
2909         /* This should not happen, because a removal patch that leaves
2910          * contents are marked "rejected" at the patch level.
2911          */
2912         if (!patch->new_name)
2913                 die("internal error");
2914
2915         /* Say this even without --verbose */
2916         say_patch_name(stderr, "Applying patch ", patch, " with");
2917         fprintf(stderr, " %d rejects...\n", cnt);
2918
2919         cnt = strlen(patch->new_name);
2920         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2921                 cnt = ARRAY_SIZE(namebuf) - 5;
2922                 fprintf(stderr,
2923                         "warning: truncating .rej filename to %.*s.rej",
2924                         cnt - 1, patch->new_name);
2925         }
2926         memcpy(namebuf, patch->new_name, cnt);
2927         memcpy(namebuf + cnt, ".rej", 5);
2928
2929         rej = fopen(namebuf, "w");
2930         if (!rej)
2931                 return error("cannot open %s: %s", namebuf, strerror(errno));
2932
2933         /* Normal git tools never deal with .rej, so do not pretend
2934          * this is a git patch by saying --git nor give extended
2935          * headers.  While at it, maybe please "kompare" that wants
2936          * the trailing TAB and some garbage at the end of line ;-).
2937          */
2938         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2939                 patch->new_name, patch->new_name);
2940         for (cnt = 1, frag = patch->fragments;
2941              frag;
2942              cnt++, frag = frag->next) {
2943                 if (!frag->rejected) {
2944                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2945                         continue;
2946                 }
2947                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2948                 fprintf(rej, "%.*s", frag->size, frag->patch);
2949                 if (frag->patch[frag->size-1] != '\n')
2950                         fputc('\n', rej);
2951         }
2952         fclose(rej);
2953         return -1;
2954 }
2955
2956 static int write_out_results(struct patch *list, int skipped_patch)
2957 {
2958         int phase;
2959         int errs = 0;
2960         struct patch *l;
2961
2962         if (!list && !skipped_patch)
2963                 return error("No changes");
2964
2965         for (phase = 0; phase < 2; phase++) {
2966                 l = list;
2967                 while (l) {
2968                         if (l->rejected)
2969                                 errs = 1;
2970                         else {
2971                                 write_out_one_result(l, phase);
2972                                 if (phase == 1 && write_out_one_reject(l))
2973                                         errs = 1;
2974                         }
2975                         l = l->next;
2976                 }
2977         }
2978         return errs;
2979 }
2980
2981 static struct lock_file lock_file;
2982
2983 static struct string_list limit_by_name;
2984 static int has_include;
2985 static void add_name_limit(const char *name, int exclude)
2986 {
2987         struct string_list_item *it;
2988
2989         it = string_list_append(name, &limit_by_name);
2990         it->util = exclude ? NULL : (void *) 1;
2991 }
2992
2993 static int use_patch(struct patch *p)
2994 {
2995         const char *pathname = p->new_name ? p->new_name : p->old_name;
2996         int i;
2997
2998         /* Paths outside are not touched regardless of "--include" */
2999         if (0 < prefix_length) {
3000                 int pathlen = strlen(pathname);
3001                 if (pathlen <= prefix_length ||
3002                     memcmp(prefix, pathname, prefix_length))
3003                         return 0;
3004         }
3005
3006         /* See if it matches any of exclude/include rule */
3007         for (i = 0; i < limit_by_name.nr; i++) {
3008                 struct string_list_item *it = &limit_by_name.items[i];
3009                 if (!fnmatch(it->string, pathname, 0))
3010                         return (it->util != NULL);
3011         }
3012
3013         /*
3014          * If we had any include, a path that does not match any rule is
3015          * not used.  Otherwise, we saw bunch of exclude rules (or none)
3016          * and such a path is used.
3017          */
3018         return !has_include;
3019 }
3020
3021
3022 static void prefix_one(char **name)
3023 {
3024         char *old_name = *name;
3025         if (!old_name)
3026                 return;
3027         *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
3028         free(old_name);
3029 }
3030
3031 static void prefix_patches(struct patch *p)
3032 {
3033         if (!prefix || p->is_toplevel_relative)
3034                 return;
3035         for ( ; p; p = p->next) {
3036                 if (p->new_name == p->old_name) {
3037                         char *prefixed = p->new_name;
3038                         prefix_one(&prefixed);
3039                         p->new_name = p->old_name = prefixed;
3040                 }
3041                 else {
3042                         prefix_one(&p->new_name);
3043                         prefix_one(&p->old_name);
3044                 }
3045         }
3046 }
3047
3048 #define INACCURATE_EOF  (1<<0)
3049 #define RECOUNT         (1<<1)
3050
3051 static int apply_patch(int fd, const char *filename, int options)
3052 {
3053         size_t offset;
3054         struct strbuf buf = STRBUF_INIT;
3055         struct patch *list = NULL, **listp = &list;
3056         int skipped_patch = 0;
3057
3058         /* FIXME - memory leak when using multiple patch files as inputs */
3059         memset(&fn_table, 0, sizeof(struct string_list));
3060         patch_input_file = filename;
3061         read_patch_file(&buf, fd);
3062         offset = 0;
3063         while (offset < buf.len) {
3064                 struct patch *patch;
3065                 int nr;
3066
3067                 patch = xcalloc(1, sizeof(*patch));
3068                 patch->inaccurate_eof = !!(options & INACCURATE_EOF);
3069                 patch->recount =  !!(options & RECOUNT);
3070                 nr = parse_chunk(buf.buf + offset, buf.len - offset, patch);
3071                 if (nr < 0)
3072                         break;
3073                 if (apply_in_reverse)
3074                         reverse_patches(patch);
3075                 if (prefix)
3076                         prefix_patches(patch);
3077                 if (use_patch(patch)) {
3078                         patch_stats(patch);
3079                         *listp = patch;
3080                         listp = &patch->next;
3081                 }
3082                 else {
3083                         /* perhaps free it a bit better? */
3084                         free(patch);
3085                         skipped_patch++;
3086                 }
3087                 offset += nr;
3088         }
3089
3090         if (whitespace_error && (ws_error_action == die_on_ws_error))
3091                 apply = 0;
3092
3093         update_index = check_index && apply;
3094         if (update_index && newfd < 0)
3095                 newfd = hold_locked_index(&lock_file, 1);
3096
3097         if (check_index) {
3098                 if (read_cache() < 0)
3099                         die("unable to read index file");
3100         }
3101
3102         if ((check || apply) &&
3103             check_patch_list(list) < 0 &&
3104             !apply_with_reject)
3105                 exit(1);
3106
3107         if (apply && write_out_results(list, skipped_patch))
3108                 exit(1);
3109
3110         if (fake_ancestor)
3111                 build_fake_ancestor(list, fake_ancestor);
3112
3113         if (diffstat)
3114                 stat_patch_list(list);
3115
3116         if (numstat)
3117                 numstat_patch_list(list);
3118
3119         if (summary)
3120                 summary_patch_list(list);
3121
3122         strbuf_release(&buf);
3123         return 0;
3124 }
3125
3126 static int git_apply_config(const char *var, const char *value, void *cb)
3127 {
3128         if (!strcmp(var, "apply.whitespace"))
3129                 return git_config_string(&apply_default_whitespace, var, value);
3130         return git_default_config(var, value, cb);
3131 }
3132
3133
3134 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
3135 {
3136         int i;
3137         int read_stdin = 1;
3138         int options = 0;
3139         int errs = 0;
3140         int is_not_gitdir;
3141
3142         const char *whitespace_option = NULL;
3143
3144         prefix = setup_git_directory_gently(&is_not_gitdir);
3145         prefix_length = prefix ? strlen(prefix) : 0;
3146         git_config(git_apply_config, NULL);
3147         if (apply_default_whitespace)
3148                 parse_whitespace_option(apply_default_whitespace);
3149
3150         for (i = 1; i < argc; i++) {
3151                 const char *arg = argv[i];
3152                 char *end;
3153                 int fd;
3154
3155                 if (!strcmp(arg, "-")) {
3156                         errs |= apply_patch(0, "<stdin>", options);
3157                         read_stdin = 0;
3158                         continue;
3159                 }
3160                 if (!prefixcmp(arg, "--exclude=")) {
3161                         add_name_limit(arg + 10, 1);
3162                         continue;
3163                 }
3164                 if (!prefixcmp(arg, "--include=")) {
3165                         add_name_limit(arg + 10, 0);
3166                         has_include = 1;
3167                         continue;
3168                 }
3169                 if (!prefixcmp(arg, "-p")) {
3170                         p_value = atoi(arg + 2);
3171                         p_value_known = 1;
3172                         continue;
3173                 }
3174                 if (!strcmp(arg, "--no-add")) {
3175                         no_add = 1;
3176                         continue;
3177                 }
3178                 if (!strcmp(arg, "--stat")) {
3179                         apply = 0;
3180                         diffstat = 1;
3181                         continue;
3182                 }
3183                 if (!strcmp(arg, "--allow-binary-replacement") ||
3184                     !strcmp(arg, "--binary")) {
3185                         continue; /* now no-op */
3186                 }
3187                 if (!strcmp(arg, "--numstat")) {
3188                         apply = 0;
3189                         numstat = 1;
3190                         continue;
3191                 }
3192                 if (!strcmp(arg, "--summary")) {
3193                         apply = 0;
3194                         summary = 1;
3195                         continue;
3196                 }
3197                 if (!strcmp(arg, "--check")) {
3198                         apply = 0;
3199                         check = 1;
3200                         continue;
3201                 }
3202                 if (!strcmp(arg, "--index")) {
3203                         if (is_not_gitdir)
3204                                 die("--index outside a repository");
3205                         check_index = 1;
3206                         continue;
3207                 }
3208                 if (!strcmp(arg, "--cached")) {
3209                         if (is_not_gitdir)
3210                                 die("--cached outside a repository");
3211                         check_index = 1;
3212                         cached = 1;
3213                         continue;
3214                 }
3215                 if (!strcmp(arg, "--apply")) {
3216                         apply = 1;
3217                         continue;
3218                 }
3219                 if (!strcmp(arg, "--build-fake-ancestor")) {
3220                         apply = 0;
3221                         if (++i >= argc)
3222                                 die ("need a filename");
3223                         fake_ancestor = argv[i];
3224                         continue;
3225                 }
3226                 if (!strcmp(arg, "-z")) {
3227                         line_termination = 0;
3228                         continue;
3229                 }
3230                 if (!prefixcmp(arg, "-C")) {
3231                         p_context = strtoul(arg + 2, &end, 0);
3232                         if (*end != '\0')
3233                                 die("unrecognized context count '%s'", arg + 2);
3234                         continue;
3235                 }
3236                 if (!prefixcmp(arg, "--whitespace=")) {
3237                         whitespace_option = arg + 13;
3238                         parse_whitespace_option(arg + 13);
3239                         continue;
3240                 }
3241                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
3242                         apply_in_reverse = 1;
3243                         continue;
3244                 }
3245                 if (!strcmp(arg, "--unidiff-zero")) {
3246                         unidiff_zero = 1;
3247                         continue;
3248                 }
3249                 if (!strcmp(arg, "--reject")) {
3250                         apply = apply_with_reject = apply_verbosely = 1;
3251                         continue;
3252                 }
3253                 if (!strcmp(arg, "-v") || !strcmp(arg, "--verbose")) {
3254                         apply_verbosely = 1;
3255                         continue;
3256                 }
3257                 if (!strcmp(arg, "--inaccurate-eof")) {
3258                         options |= INACCURATE_EOF;
3259                         continue;
3260                 }
3261                 if (!strcmp(arg, "--recount")) {
3262                         options |= RECOUNT;
3263                         continue;
3264                 }
3265                 if (!prefixcmp(arg, "--directory=")) {
3266                         arg += strlen("--directory=");
3267                         root_len = strlen(arg);
3268                         if (root_len && arg[root_len - 1] != '/') {
3269                                 char *new_root;
3270                                 root = new_root = xmalloc(root_len + 2);
3271                                 strcpy(new_root, arg);
3272                                 strcpy(new_root + root_len++, "/");
3273                         } else
3274                                 root = arg;
3275                         continue;
3276                 }
3277                 if (0 < prefix_length)
3278                         arg = prefix_filename(prefix, prefix_length, arg);
3279
3280                 fd = open(arg, O_RDONLY);
3281                 if (fd < 0)
3282                         die("can't open patch '%s': %s", arg, strerror(errno));
3283                 read_stdin = 0;
3284                 set_default_whitespace_mode(whitespace_option);
3285                 errs |= apply_patch(fd, arg, options);
3286                 close(fd);
3287         }
3288         set_default_whitespace_mode(whitespace_option);
3289         if (read_stdin)
3290                 errs |= apply_patch(0, "<stdin>", options);
3291         if (whitespace_error) {
3292                 if (squelch_whitespace_errors &&
3293                     squelch_whitespace_errors < whitespace_error) {
3294                         int squelched =
3295                                 whitespace_error - squelch_whitespace_errors;
3296                         fprintf(stderr, "warning: squelched %d "
3297                                 "whitespace error%s\n",
3298                                 squelched,
3299                                 squelched == 1 ? "" : "s");
3300                 }
3301                 if (ws_error_action == die_on_ws_error)
3302                         die("%d line%s add%s whitespace errors.",
3303                             whitespace_error,
3304                             whitespace_error == 1 ? "" : "s",
3305                             whitespace_error == 1 ? "s" : "");
3306                 if (applied_after_fixing_ws && apply)
3307                         fprintf(stderr, "warning: %d line%s applied after"
3308                                 " fixing whitespace errors.\n",
3309                                 applied_after_fixing_ws,
3310                                 applied_after_fixing_ws == 1 ? "" : "s");
3311                 else if (whitespace_error)
3312                         fprintf(stderr, "warning: %d line%s add%s whitespace errors.\n",
3313                                 whitespace_error,
3314                                 whitespace_error == 1 ? "" : "s",
3315                                 whitespace_error == 1 ? "s" : "");
3316         }
3317
3318         if (update_index) {
3319                 if (write_cache(newfd, active_cache, active_nr) ||
3320                     commit_locked_index(&lock_file))
3321                         die("Unable to write new index file");
3322         }
3323
3324         return !!errs;
3325 }