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->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         if (patch->def_name && root) {
 809                 char *s = xmalloc(root_len + strlen(patch->def_name) + 1);
 810                 strcpy(s, root);
 811                 strcpy(s + root_len, patch->def_name);
 812                 free(patch->def_name);
 813                 patch->def_name = s;
 814         }
 815
 816         line += len;
 817         size -= len;
 818         linenr++;
 819         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
 820                 static const struct opentry {
 821                         const char *str;
 822                         int (*fn)(const char *, struct patch *);
 823                 } optable[] = {
 824                         { "@@ -", gitdiff_hdrend },
 825                         { "--- ", gitdiff_oldname },
 826                         { "+++ ", gitdiff_newname },
 827                         { "old mode ", gitdiff_oldmode },
 828                         { "new mode ", gitdiff_newmode },
 829                         { "deleted file mode ", gitdiff_delete },
 830                         { "new file mode ", gitdiff_newfile },
 831                         { "copy from ", gitdiff_copysrc },
 832                         { "copy to ", gitdiff_copydst },
 833                         { "rename old ", gitdiff_renamesrc },
 834                         { "rename new ", gitdiff_renamedst },
 835                         { "rename from ", gitdiff_renamesrc },
 836                         { "rename to ", gitdiff_renamedst },
 837                         { "similarity index ", gitdiff_similarity },
 838                         { "dissimilarity index ", gitdiff_dissimilarity },
 839                         { "index ", gitdiff_index },
 840                         { "", gitdiff_unrecognized },
 841                 };
 842                 int i;
 843
 844                 len = linelen(line, size);
 845                 if (!len || line[len-1] != '\n')
 846                         break;
 847                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
 848                         const struct opentry *p = optable + i;
 849                         int oplen = strlen(p->str);
 850                         if (len < oplen || memcmp(p->str, line, oplen))
 851                                 continue;
 852                         if (p->fn(line + oplen, patch) < 0)
 853                                 return offset;
 854                         break;
 855                 }
 856         }
 857
 858         return offset;
 859 }
 860
 861 static int parse_num(const char *line, unsigned long *p)
 862 {
 863         char *ptr;
 864
 865         if (!isdigit(*line))
 866                 return 0;
 867         *p = strtoul(line, &ptr, 10);
 868         return ptr - line;
 869 }
 870
 871 static int parse_range(const char *line, int len, int offset, const char *expect,
 872                        unsigned long *p1, unsigned long *p2)
 873 {
 874         int digits, ex;
 875
 876         if (offset < 0 || offset >= len)
 877                 return -1;
 878         line += offset;
 879         len -= offset;
 880
 881         digits = parse_num(line, p1);
 882         if (!digits)
 883                 return -1;
 884
 885         offset += digits;
 886         line += digits;
 887         len -= digits;
 888
 889         *p2 = 1;
 890         if (*line == ',') {
 891                 digits = parse_num(line+1, p2);
 892                 if (!digits)
 893                         return -1;
 894
 895                 offset += digits+1;
 896                 line += digits+1;
 897                 len -= digits+1;
 898         }
 899
 900         ex = strlen(expect);
 901         if (ex > len)
 902                 return -1;
 903         if (memcmp(line, expect, ex))
 904                 return -1;
 905
 906         return offset + ex;
 907 }
 908
 909 static void recount_diff(char *line, int size, struct fragment *fragment)
 910 {
 911         int oldlines = 0, newlines = 0, ret = 0;
 912
 913         if (size < 1) {
 914                 warning("recount: ignore empty hunk");
 915                 return;
 916         }
 917
 918         for (;;) {
 919                 int len = linelen(line, size);
 920                 size -= len;
 921                 line += len;
 922
 923                 if (size < 1)
 924                         break;
 925
 926                 switch (*line) {
 927                 case ' ': case '\n':
 928                         newlines++;
 929                         /* fall through */
 930                 case '-':
 931                         oldlines++;
 932                         continue;
 933                 case '+':
 934                         newlines++;
 935                         continue;
 936                 case '\\':
 937                         continue;
 938                 case '@':
 939                         ret = size < 3 || prefixcmp(line, "@@ ");
 940                         break;
 941                 case 'd':
 942                         ret = size < 5 || prefixcmp(line, "diff ");
 943                         break;
 944                 default:
 945                         ret = -1;
 946                         break;
 947                 }
 948                 if (ret) {
 949                         warning("recount: unexpected line: %.*s",
 950                                 (int)linelen(line, size), line);
 951                         return;
 952                 }
 953                 break;
 954         }
 955         fragment->oldlines = oldlines;
 956         fragment->newlines = newlines;
 957 }
 958
 959 /*
 960  * Parse a unified diff fragment header of the
 961  * form "@@ -a,b +c,d @@"
 962  */
 963 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
 964 {
 965         int offset;
 966
 967         if (!len || line[len-1] != '\n')
 968                 return -1;
 969
 970         /* Figure out the number of lines in a fragment */
 971         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
 972         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 973
 974         return offset;
 975 }
 976
 977 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
 978 {
 979         unsigned long offset, len;
 980
 981         patch->is_toplevel_relative = 0;
 982         patch->is_rename = patch->is_copy = 0;
 983         patch->is_new = patch->is_delete = -1;
 984         patch->old_mode = patch->new_mode = 0;
 985         patch->old_name = patch->new_name = NULL;
 986         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
 987                 unsigned long nextlen;
 988
 989                 len = linelen(line, size);
 990                 if (!len)
 991                         break;
 992
 993                 /* Testing this early allows us to take a few shortcuts.. */
 994                 if (len < 6)
 995                         continue;
 996
 997                 /*
 998                  * Make sure we don't find any unconnected patch fragments.
 999                  * That's a sign that we didn't find a header, and that a
1000                  * patch has become corrupted/broken up.
1001                  */
1002                 if (!memcmp("@@ -", line, 4)) {
1003                         struct fragment dummy;
1004                         if (parse_fragment_header(line, len, &dummy) < 0)
1005                                 continue;
1006                         die("patch fragment without header at line %d: %.*s",
1007                             linenr, (int)len-1, line);
1008                 }
1009
1010                 if (size < len + 6)
1011                         break;
1012
1013                 /*
1014                  * Git patch? It might not have a real patch, just a rename
1015                  * or mode change, so we handle that specially
1016                  */
1017                 if (!memcmp("diff --git ", line, 11)) {
1018                         int git_hdr_len = parse_git_header(line, len, size, patch);
1019                         if (git_hdr_len <= len)
1020                                 continue;
1021                         if (!patch->old_name && !patch->new_name) {
1022                                 if (!patch->def_name)
1023                                         die("git diff header lacks filename information (line %d)", linenr);
1024                                 patch->old_name = patch->new_name = patch->def_name;
1025                         }
1026                         patch->is_toplevel_relative = 1;
1027                         *hdrsize = git_hdr_len;
1028                         return offset;
1029                 }
1030
1031                 /* --- followed by +++ ? */
1032                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1033                         continue;
1034
1035                 /*
1036                  * We only accept unified patches, so we want it to
1037                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1038                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1039                  */
1040                 nextlen = linelen(line + len, size - len);
1041                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1042                         continue;
1043
1044                 /* Ok, we'll consider it a patch */
1045                 parse_traditional_patch(line, line+len, patch);
1046                 *hdrsize = len + nextlen;
1047                 linenr += 2;
1048                 return offset;
1049         }
1050         return -1;
1051 }
1052
1053 static void check_whitespace(const char *line, int len, unsigned ws_rule)
1054 {
1055         char *err;
1056         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1057         if (!result)
1058                 return;
1059
1060         whitespace_error++;
1061         if (squelch_whitespace_errors &&
1062             squelch_whitespace_errors < whitespace_error)
1063                 ;
1064         else {
1065                 err = whitespace_error_string(result);
1066                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1067                         patch_input_file, linenr, err, len - 2, line + 1);
1068                 free(err);
1069         }
1070 }
1071
1072 /*
1073  * Parse a unified diff. Note that this really needs to parse each
1074  * fragment separately, since the only way to know the difference
1075  * between a "---" that is part of a patch, and a "---" that starts
1076  * the next patch is to look at the line counts..
1077  */
1078 static int parse_fragment(char *line, unsigned long size,
1079                           struct patch *patch, struct fragment *fragment)
1080 {
1081         int added, deleted;
1082         int len = linelen(line, size), offset;
1083         unsigned long oldlines, newlines;
1084         unsigned long leading, trailing;
1085
1086         offset = parse_fragment_header(line, len, fragment);
1087         if (offset < 0)
1088                 return -1;
1089         if (offset > 0 && patch->recount)
1090                 recount_diff(line + offset, size - offset, fragment);
1091         oldlines = fragment->oldlines;
1092         newlines = fragment->newlines;
1093         leading = 0;
1094         trailing = 0;
1095
1096         /* Parse the thing.. */
1097         line += len;
1098         size -= len;
1099         linenr++;
1100         added = deleted = 0;
1101         for (offset = len;
1102              0 < size;
1103              offset += len, size -= len, line += len, linenr++) {
1104                 if (!oldlines && !newlines)
1105                         break;
1106                 len = linelen(line, size);
1107                 if (!len || line[len-1] != '\n')
1108                         return -1;
1109                 switch (*line) {
1110                 default:
1111                         return -1;
1112                 case '\n': /* newer GNU diff, an empty context line */
1113                 case ' ':
1114                         oldlines--;
1115                         newlines--;
1116                         if (!deleted && !added)
1117                                 leading++;
1118                         trailing++;
1119                         break;
1120                 case '-':
1121                         if (apply_in_reverse &&
1122                             ws_error_action != nowarn_ws_error)
1123                                 check_whitespace(line, len, patch->ws_rule);
1124                         deleted++;
1125                         oldlines--;
1126                         trailing = 0;
1127                         break;
1128                 case '+':
1129                         if (!apply_in_reverse &&
1130                             ws_error_action != nowarn_ws_error)
1131                                 check_whitespace(line, len, patch->ws_rule);
1132                         added++;
1133                         newlines--;
1134                         trailing = 0;
1135                         break;
1136
1137                 /*
1138                  * We allow "\ No newline at end of file". Depending
1139                  * on locale settings when the patch was produced we
1140                  * don't know what this line looks like. The only
1141                  * thing we do know is that it begins with "\ ".
1142                  * Checking for 12 is just for sanity check -- any
1143                  * l10n of "\ No newline..." is at least that long.
1144                  */
1145                 case '\\':
1146                         if (len < 12 || memcmp(line, "\\ ", 2))
1147                                 return -1;
1148                         break;
1149                 }
1150         }
1151         if (oldlines || newlines)
1152                 return -1;
1153         fragment->leading = leading;
1154         fragment->trailing = trailing;
1155
1156         /*
1157          * If a fragment ends with an incomplete line, we failed to include
1158          * it in the above loop because we hit oldlines == newlines == 0
1159          * before seeing it.
1160          */
1161         if (12 < size && !memcmp(line, "\\ ", 2))
1162                 offset += linelen(line, size);
1163
1164         patch->lines_added += added;
1165         patch->lines_deleted += deleted;
1166
1167         if (0 < patch->is_new && oldlines)
1168                 return error("new file depends on old contents");
1169         if (0 < patch->is_delete && newlines)
1170                 return error("deleted file still has contents");
1171         return offset;
1172 }
1173
1174 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1175 {
1176         unsigned long offset = 0;
1177         unsigned long oldlines = 0, newlines = 0, context = 0;
1178         struct fragment **fragp = &patch->fragments;
1179
1180         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1181                 struct fragment *fragment;
1182                 int len;
1183
1184                 fragment = xcalloc(1, sizeof(*fragment));
1185                 len = parse_fragment(line, size, patch, fragment);
1186                 if (len <= 0)
1187                         die("corrupt patch at line %d", linenr);
1188                 fragment->patch = line;
1189                 fragment->size = len;
1190                 oldlines += fragment->oldlines;
1191                 newlines += fragment->newlines;
1192                 context += fragment->leading + fragment->trailing;
1193
1194                 *fragp = fragment;
1195                 fragp = &fragment->next;
1196
1197                 offset += len;
1198                 line += len;
1199                 size -= len;
1200         }
1201
1202         /*
1203          * If something was removed (i.e. we have old-lines) it cannot
1204          * be creation, and if something was added it cannot be
1205          * deletion.  However, the reverse is not true; --unified=0
1206          * patches that only add are not necessarily creation even
1207          * though they do not have any old lines, and ones that only
1208          * delete are not necessarily deletion.
1209          *
1210          * Unfortunately, a real creation/deletion patch do _not_ have
1211          * any context line by definition, so we cannot safely tell it
1212          * apart with --unified=0 insanity.  At least if the patch has
1213          * more than one hunk it is not creation or deletion.
1214          */
1215         if (patch->is_new < 0 &&
1216             (oldlines || (patch->fragments && patch->fragments->next)))
1217                 patch->is_new = 0;
1218         if (patch->is_delete < 0 &&
1219             (newlines || (patch->fragments && patch->fragments->next)))
1220                 patch->is_delete = 0;
1221
1222         if (0 < patch->is_new && oldlines)
1223                 die("new file %s depends on old contents", patch->new_name);
1224         if (0 < patch->is_delete && newlines)
1225                 die("deleted file %s still has contents", patch->old_name);
1226         if (!patch->is_delete && !newlines && context)
1227                 fprintf(stderr, "** warning: file %s becomes empty but "
1228                         "is not deleted\n", patch->new_name);
1229
1230         return offset;
1231 }
1232
1233 static inline int metadata_changes(struct patch *patch)
1234 {
1235         return  patch->is_rename > 0 ||
1236                 patch->is_copy > 0 ||
1237                 patch->is_new > 0 ||
1238                 patch->is_delete ||
1239                 (patch->old_mode && patch->new_mode &&
1240                  patch->old_mode != patch->new_mode);
1241 }
1242
1243 static char *inflate_it(const void *data, unsigned long size,
1244                         unsigned long inflated_size)
1245 {
1246         z_stream stream;
1247         void *out;
1248         int st;
1249
1250         memset(&stream, 0, sizeof(stream));
1251
1252         stream.next_in = (unsigned char *)data;
1253         stream.avail_in = size;
1254         stream.next_out = out = xmalloc(inflated_size);
1255         stream.avail_out = inflated_size;
1256         inflateInit(&stream);
1257         st = inflate(&stream, Z_FINISH);
1258         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1259                 free(out);
1260                 return NULL;
1261         }
1262         return out;
1263 }
1264
1265 static struct fragment *parse_binary_hunk(char **buf_p,
1266                                           unsigned long *sz_p,
1267                                           int *status_p,
1268                                           int *used_p)
1269 {
1270         /*
1271          * Expect a line that begins with binary patch method ("literal"
1272          * or "delta"), followed by the length of data before deflating.
1273          * a sequence of 'length-byte' followed by base-85 encoded data
1274          * should follow, terminated by a newline.
1275          *
1276          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1277          * and we would limit the patch line to 66 characters,
1278          * so one line can fit up to 13 groups that would decode
1279          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1280          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1281          */
1282         int llen, used;
1283         unsigned long size = *sz_p;
1284         char *buffer = *buf_p;
1285         int patch_method;
1286         unsigned long origlen;
1287         char *data = NULL;
1288         int hunk_size = 0;
1289         struct fragment *frag;
1290
1291         llen = linelen(buffer, size);
1292         used = llen;
1293
1294         *status_p = 0;
1295
1296         if (!prefixcmp(buffer, "delta ")) {
1297                 patch_method = BINARY_DELTA_DEFLATED;
1298                 origlen = strtoul(buffer + 6, NULL, 10);
1299         }
1300         else if (!prefixcmp(buffer, "literal ")) {
1301                 patch_method = BINARY_LITERAL_DEFLATED;
1302                 origlen = strtoul(buffer + 8, NULL, 10);
1303         }
1304         else
1305                 return NULL;
1306
1307         linenr++;
1308         buffer += llen;
1309         while (1) {
1310                 int byte_length, max_byte_length, newsize;
1311                 llen = linelen(buffer, size);
1312                 used += llen;
1313                 linenr++;
1314                 if (llen == 1) {
1315                         /* consume the blank line */
1316                         buffer++;
1317                         size--;
1318                         break;
1319                 }
1320                 /*
1321                  * Minimum line is "A00000\n" which is 7-byte long,
1322                  * and the line length must be multiple of 5 plus 2.
1323                  */
1324                 if ((llen < 7) || (llen-2) % 5)
1325                         goto corrupt;
1326                 max_byte_length = (llen - 2) / 5 * 4;
1327                 byte_length = *buffer;
1328                 if ('A' <= byte_length && byte_length <= 'Z')
1329                         byte_length = byte_length - 'A' + 1;
1330                 else if ('a' <= byte_length && byte_length <= 'z')
1331                         byte_length = byte_length - 'a' + 27;
1332                 else
1333                         goto corrupt;
1334                 /* if the input length was not multiple of 4, we would
1335                  * have filler at the end but the filler should never
1336                  * exceed 3 bytes
1337                  */
1338                 if (max_byte_length < byte_length ||
1339                     byte_length <= max_byte_length - 4)
1340                         goto corrupt;
1341                 newsize = hunk_size + byte_length;
1342                 data = xrealloc(data, newsize);
1343                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1344                         goto corrupt;
1345                 hunk_size = newsize;
1346                 buffer += llen;
1347                 size -= llen;
1348         }
1349
1350         frag = xcalloc(1, sizeof(*frag));
1351         frag->patch = inflate_it(data, hunk_size, origlen);
1352         if (!frag->patch)
1353                 goto corrupt;
1354         free(data);
1355         frag->size = origlen;
1356         *buf_p = buffer;
1357         *sz_p = size;
1358         *used_p = used;
1359         frag->binary_patch_method = patch_method;
1360         return frag;
1361
1362  corrupt:
1363         free(data);
1364         *status_p = -1;
1365         error("corrupt binary patch at line %d: %.*s",
1366               linenr-1, llen-1, buffer);
1367         return NULL;
1368 }
1369
1370 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1371 {
1372         /*
1373          * We have read "GIT binary patch\n"; what follows is a line
1374          * that says the patch method (currently, either "literal" or
1375          * "delta") and the length of data before deflating; a
1376          * sequence of 'length-byte' followed by base-85 encoded data
1377          * follows.
1378          *
1379          * When a binary patch is reversible, there is another binary
1380          * hunk in the same format, starting with patch method (either
1381          * "literal" or "delta") with the length of data, and a sequence
1382          * of length-byte + base-85 encoded data, terminated with another
1383          * empty line.  This data, when applied to the postimage, produces
1384          * the preimage.
1385          */
1386         struct fragment *forward;
1387         struct fragment *reverse;
1388         int status;
1389         int used, used_1;
1390
1391         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1392         if (!forward && !status)
1393                 /* there has to be one hunk (forward hunk) */
1394                 return error("unrecognized binary patch at line %d", linenr-1);
1395         if (status)
1396                 /* otherwise we already gave an error message */
1397                 return status;
1398
1399         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1400         if (reverse)
1401                 used += used_1;
1402         else if (status) {
1403                 /*
1404                  * Not having reverse hunk is not an error, but having
1405                  * a corrupt reverse hunk is.
1406                  */
1407                 free((void*) forward->patch);
1408                 free(forward);
1409                 return status;
1410         }
1411         forward->next = reverse;
1412         patch->fragments = forward;
1413         patch->is_binary = 1;
1414         return used;
1415 }
1416
1417 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1418 {
1419         int hdrsize, patchsize;
1420         int offset = find_header(buffer, size, &hdrsize, patch);
1421
1422         if (offset < 0)
1423                 return offset;
1424
1425         patch->ws_rule = whitespace_rule(patch->new_name
1426                                          ? patch->new_name
1427                                          : patch->old_name);
1428
1429         patchsize = parse_single_patch(buffer + offset + hdrsize,
1430                                        size - offset - hdrsize, patch);
1431
1432         if (!patchsize) {
1433                 static const char *binhdr[] = {
1434                         "Binary files ",
1435                         "Files ",
1436                         NULL,
1437                 };
1438                 static const char git_binary[] = "GIT binary patch\n";
1439                 int i;
1440                 int hd = hdrsize + offset;
1441                 unsigned long llen = linelen(buffer + hd, size - hd);
1442
1443                 if (llen == sizeof(git_binary) - 1 &&
1444                     !memcmp(git_binary, buffer + hd, llen)) {
1445                         int used;
1446                         linenr++;
1447                         used = parse_binary(buffer + hd + llen,
1448                                             size - hd - llen, patch);
1449                         if (used)
1450                                 patchsize = used + llen;
1451                         else
1452                                 patchsize = 0;
1453                 }
1454                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1455                         for (i = 0; binhdr[i]; i++) {
1456                                 int len = strlen(binhdr[i]);
1457                                 if (len < size - hd &&
1458                                     !memcmp(binhdr[i], buffer + hd, len)) {
1459                                         linenr++;
1460                                         patch->is_binary = 1;
1461                                         patchsize = llen;
1462                                         break;
1463                                 }
1464                         }
1465                 }
1466
1467                 /* Empty patch cannot be applied if it is a text patch
1468                  * without metadata change.  A binary patch appears
1469                  * empty to us here.
1470                  */
1471                 if ((apply || check) &&
1472                     (!patch->is_binary && !metadata_changes(patch)))
1473                         die("patch with only garbage at line %d", linenr);
1474         }
1475
1476         return offset + hdrsize + patchsize;
1477 }
1478
1479 #define swap(a,b) myswap((a),(b),sizeof(a))
1480
1481 #define myswap(a, b, size) do {         \
1482         unsigned char mytmp[size];      \
1483         memcpy(mytmp, &a, size);                \
1484         memcpy(&a, &b, size);           \
1485         memcpy(&b, mytmp, size);                \
1486 } while (0)
1487
1488 static void reverse_patches(struct patch *p)
1489 {
1490         for (; p; p = p->next) {
1491                 struct fragment *frag = p->fragments;
1492
1493                 swap(p->new_name, p->old_name);
1494                 swap(p->new_mode, p->old_mode);
1495                 swap(p->is_new, p->is_delete);
1496                 swap(p->lines_added, p->lines_deleted);
1497                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1498
1499                 for (; frag; frag = frag->next) {
1500                         swap(frag->newpos, frag->oldpos);
1501                         swap(frag->newlines, frag->oldlines);
1502                 }
1503         }
1504 }
1505
1506 static const char pluses[] =
1507 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1508 static const char minuses[]=
1509 "----------------------------------------------------------------------";
1510
1511 static void show_stats(struct patch *patch)
1512 {
1513         struct strbuf qname = STRBUF_INIT;
1514         char *cp = patch->new_name ? patch->new_name : patch->old_name;
1515         int max, add, del;
1516
1517         quote_c_style(cp, &qname, NULL, 0);
1518
1519         /*
1520          * "scale" the filename
1521          */
1522         max = max_len;
1523         if (max > 50)
1524                 max = 50;
1525
1526         if (qname.len > max) {
1527                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
1528                 if (!cp)
1529                         cp = qname.buf + qname.len + 3 - max;
1530                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
1531         }
1532
1533         if (patch->is_binary) {
1534                 printf(" %-*s |  Bin\n", max, qname.buf);
1535                 strbuf_release(&qname);
1536                 return;
1537         }
1538
1539         printf(" %-*s |", max, qname.buf);
1540         strbuf_release(&qname);
1541
1542         /*
1543          * scale the add/delete
1544          */
1545         max = max + max_change > 70 ? 70 - max : max_change;
1546         add = patch->lines_added;
1547         del = patch->lines_deleted;
1548
1549         if (max_change > 0) {
1550                 int total = ((add + del) * max + max_change / 2) / max_change;
1551                 add = (add * max + max_change / 2) / max_change;
1552                 del = total - add;
1553         }
1554         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
1555                 add, pluses, del, minuses);
1556 }
1557
1558 static int read_old_data(struct stat *st, const char *path, struct strbuf *buf)
1559 {
1560         switch (st->st_mode & S_IFMT) {
1561         case S_IFLNK:
1562                 if (strbuf_readlink(buf, path, st->st_size) < 0)
1563                         return error("unable to read symlink %s", path);
1564                 return 0;
1565         case S_IFREG:
1566                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
1567                         return error("unable to open or read %s", path);
1568                 convert_to_git(path, buf->buf, buf->len, buf, 0);
1569                 return 0;
1570         default:
1571                 return -1;
1572         }
1573 }
1574
1575 static void update_pre_post_images(struct image *preimage,
1576                                    struct image *postimage,
1577                                    char *buf,
1578                                    size_t len)
1579 {
1580         int i, ctx;
1581         char *new, *old, *fixed;
1582         struct image fixed_preimage;
1583
1584         /*
1585          * Update the preimage with whitespace fixes.  Note that we
1586          * are not losing preimage->buf -- apply_one_fragment() will
1587          * free "oldlines".
1588          */
1589         prepare_image(&fixed_preimage, buf, len, 1);
1590         assert(fixed_preimage.nr == preimage->nr);
1591         for (i = 0; i < preimage->nr; i++)
1592                 fixed_preimage.line[i].flag = preimage->line[i].flag;
1593         free(preimage->line_allocated);
1594         *preimage = fixed_preimage;
1595
1596         /*
1597          * Adjust the common context lines in postimage, in place.
1598          * This is possible because whitespace fixing does not make
1599          * the string grow.
1600          */
1601         new = old = postimage->buf;
1602         fixed = preimage->buf;
1603         for (i = ctx = 0; i < postimage->nr; i++) {
1604                 size_t len = postimage->line[i].len;
1605                 if (!(postimage->line[i].flag & LINE_COMMON)) {
1606                         /* an added line -- no counterparts in preimage */
1607                         memmove(new, old, len);
1608                         old += len;
1609                         new += len;
1610                         continue;
1611                 }
1612
1613                 /* a common context -- skip it in the original postimage */
1614                 old += len;
1615
1616                 /* and find the corresponding one in the fixed preimage */
1617                 while (ctx < preimage->nr &&
1618                        !(preimage->line[ctx].flag & LINE_COMMON)) {
1619                         fixed += preimage->line[ctx].len;
1620                         ctx++;
1621                 }
1622                 if (preimage->nr <= ctx)
1623                         die("oops");
1624
1625                 /* and copy it in, while fixing the line length */
1626                 len = preimage->line[ctx].len;
1627                 memcpy(new, fixed, len);
1628                 new += len;
1629                 fixed += len;
1630                 postimage->line[i].len = len;
1631                 ctx++;
1632         }
1633
1634         /* Fix the length of the whole thing */
1635         postimage->len = new - postimage->buf;
1636 }
1637
1638 static int match_fragment(struct image *img,
1639                           struct image *preimage,
1640                           struct image *postimage,
1641                           unsigned long try,
1642                           int try_lno,
1643                           unsigned ws_rule,
1644                           int match_beginning, int match_end)
1645 {
1646         int i;
1647         char *fixed_buf, *buf, *orig, *target;
1648
1649         if (preimage->nr + try_lno > img->nr)
1650                 return 0;
1651
1652         if (match_beginning && try_lno)
1653                 return 0;
1654
1655         if (match_end && preimage->nr + try_lno != img->nr)
1656                 return 0;
1657
1658         /* Quick hash check */
1659         for (i = 0; i < preimage->nr; i++)
1660                 if (preimage->line[i].hash != img->line[try_lno + i].hash)
1661                         return 0;
1662
1663         /*
1664          * Do we have an exact match?  If we were told to match
1665          * at the end, size must be exactly at try+fragsize,
1666          * otherwise try+fragsize must be still within the preimage,
1667          * and either case, the old piece should match the preimage
1668          * exactly.
1669          */
1670         if ((match_end
1671              ? (try + preimage->len == img->len)
1672              : (try + preimage->len <= img->len)) &&
1673             !memcmp(img->buf + try, preimage->buf, preimage->len))
1674                 return 1;
1675
1676         if (ws_error_action != correct_ws_error)
1677                 return 0;
1678
1679         /*
1680          * The hunk does not apply byte-by-byte, but the hash says
1681          * it might with whitespace fuzz.
1682          */
1683         fixed_buf = xmalloc(preimage->len + 1);
1684         buf = fixed_buf;
1685         orig = preimage->buf;
1686         target = img->buf + try;
1687         for (i = 0; i < preimage->nr; i++) {
1688                 size_t fixlen; /* length after fixing the preimage */
1689                 size_t oldlen = preimage->line[i].len;
1690                 size_t tgtlen = img->line[try_lno + i].len;
1691                 size_t tgtfixlen; /* length after fixing the target line */
1692                 char tgtfixbuf[1024], *tgtfix;
1693                 int match;
1694
1695                 /* Try fixing the line in the preimage */
1696                 fixlen = ws_fix_copy(buf, orig, oldlen, ws_rule, NULL);
1697
1698                 /* Try fixing the line in the target */
1699                 if (sizeof(tgtfixbuf) > tgtlen)
1700                         tgtfix = tgtfixbuf;
1701                 else
1702                         tgtfix = xmalloc(tgtlen);
1703                 tgtfixlen = ws_fix_copy(tgtfix, target, tgtlen, ws_rule, NULL);
1704
1705                 /*
1706                  * If they match, either the preimage was based on
1707                  * a version before our tree fixed whitespace breakage,
1708                  * or we are lacking a whitespace-fix patch the tree
1709                  * the preimage was based on already had (i.e. target
1710                  * has whitespace breakage, the preimage doesn't).
1711                  * In either case, we are fixing the whitespace breakages
1712                  * so we might as well take the fix together with their
1713                  * real change.
1714                  */
1715                 match = (tgtfixlen == fixlen && !memcmp(tgtfix, buf, fixlen));
1716
1717                 if (tgtfix != tgtfixbuf)
1718                         free(tgtfix);
1719                 if (!match)
1720                         goto unmatch_exit;
1721
1722                 orig += oldlen;
1723                 buf += fixlen;
1724                 target += tgtlen;
1725         }
1726
1727         /*
1728          * Yes, the preimage is based on an older version that still
1729          * has whitespace breakages unfixed, and fixing them makes the
1730          * hunk match.  Update the context lines in the postimage.
1731          */
1732         update_pre_post_images(preimage, postimage,
1733                                fixed_buf, buf - fixed_buf);
1734         return 1;
1735
1736  unmatch_exit:
1737         free(fixed_buf);
1738         return 0;
1739 }
1740
1741 static int find_pos(struct image *img,
1742                     struct image *preimage,
1743                     struct image *postimage,
1744                     int line,
1745                     unsigned ws_rule,
1746                     int match_beginning, int match_end)
1747 {
1748         int i;
1749         unsigned long backwards, forwards, try;
1750         int backwards_lno, forwards_lno, try_lno;
1751
1752         if (preimage->nr > img->nr)
1753                 return -1;
1754
1755         /*
1756          * If match_begining or match_end is specified, there is no
1757          * point starting from a wrong line that will never match and
1758          * wander around and wait for a match at the specified end.
1759          */
1760         if (match_beginning)
1761                 line = 0;
1762         else if (match_end)
1763                 line = img->nr - preimage->nr;
1764
1765         if (line > img->nr)
1766                 line = img->nr;
1767
1768         try = 0;
1769         for (i = 0; i < line; i++)
1770                 try += img->line[i].len;
1771
1772         /*
1773          * There's probably some smart way to do this, but I'll leave
1774          * that to the smart and beautiful people. I'm simple and stupid.
1775          */
1776         backwards = try;
1777         backwards_lno = line;
1778         forwards = try;
1779         forwards_lno = line;
1780         try_lno = line;
1781
1782         for (i = 0; ; i++) {
1783                 if (match_fragment(img, preimage, postimage,
1784                                    try, try_lno, ws_rule,
1785                                    match_beginning, match_end))
1786                         return try_lno;
1787
1788         again:
1789                 if (backwards_lno == 0 && forwards_lno == img->nr)
1790                         break;
1791
1792                 if (i & 1) {
1793                         if (backwards_lno == 0) {
1794                                 i++;
1795                                 goto again;
1796                         }
1797                         backwards_lno--;
1798                         backwards -= img->line[backwards_lno].len;
1799                         try = backwards;
1800                         try_lno = backwards_lno;
1801                 } else {
1802                         if (forwards_lno == img->nr) {
1803                                 i++;
1804                                 goto again;
1805                         }
1806                         forwards += img->line[forwards_lno].len;
1807                         forwards_lno++;
1808                         try = forwards;
1809                         try_lno = forwards_lno;
1810                 }
1811
1812         }
1813         return -1;
1814 }
1815
1816 static void remove_first_line(struct image *img)
1817 {
1818         img->buf += img->line[0].len;
1819         img->len -= img->line[0].len;
1820         img->line++;
1821         img->nr--;
1822 }
1823
1824 static void remove_last_line(struct image *img)
1825 {
1826         img->len -= img->line[--img->nr].len;
1827 }
1828
1829 static void update_image(struct image *img,
1830                          int applied_pos,
1831                          struct image *preimage,
1832                          struct image *postimage)
1833 {
1834         /*
1835          * remove the copy of preimage at offset in img
1836          * and replace it with postimage
1837          */
1838         int i, nr;
1839         size_t remove_count, insert_count, applied_at = 0;
1840         char *result;
1841
1842         for (i = 0; i < applied_pos; i++)
1843                 applied_at += img->line[i].len;
1844
1845         remove_count = 0;
1846         for (i = 0; i < preimage->nr; i++)
1847                 remove_count += img->line[applied_pos + i].len;
1848         insert_count = postimage->len;
1849
1850         /* Adjust the contents */
1851         result = xmalloc(img->len + insert_count - remove_count + 1);
1852         memcpy(result, img->buf, applied_at);
1853         memcpy(result + applied_at, postimage->buf, postimage->len);
1854         memcpy(result + applied_at + postimage->len,
1855                img->buf + (applied_at + remove_count),
1856                img->len - (applied_at + remove_count));
1857         free(img->buf);
1858         img->buf = result;
1859         img->len += insert_count - remove_count;
1860         result[img->len] = '\0';
1861
1862         /* Adjust the line table */
1863         nr = img->nr + postimage->nr - preimage->nr;
1864         if (preimage->nr < postimage->nr) {
1865                 /*
1866                  * NOTE: this knows that we never call remove_first_line()
1867                  * on anything other than pre/post image.
1868                  */
1869                 img->line = xrealloc(img->line, nr * sizeof(*img->line));
1870                 img->line_allocated = img->line;
1871         }
1872         if (preimage->nr != postimage->nr)
1873                 memmove(img->line + applied_pos + postimage->nr,
1874                         img->line + applied_pos + preimage->nr,
1875                         (img->nr - (applied_pos + preimage->nr)) *
1876                         sizeof(*img->line));
1877         memcpy(img->line + applied_pos,
1878                postimage->line,
1879                postimage->nr * sizeof(*img->line));
1880         img->nr = nr;
1881 }
1882
1883 static int apply_one_fragment(struct image *img, struct fragment *frag,
1884                               int inaccurate_eof, unsigned ws_rule)
1885 {
1886         int match_beginning, match_end;
1887         const char *patch = frag->patch;
1888         int size = frag->size;
1889         char *old, *new, *oldlines, *newlines;
1890         int new_blank_lines_at_end = 0;
1891         unsigned long leading, trailing;
1892         int pos, applied_pos;
1893         struct image preimage;
1894         struct image postimage;
1895
1896         memset(&preimage, 0, sizeof(preimage));
1897         memset(&postimage, 0, sizeof(postimage));
1898         oldlines = xmalloc(size);
1899         newlines = xmalloc(size);
1900
1901         old = oldlines;
1902         new = newlines;
1903         while (size > 0) {
1904                 char first;
1905                 int len = linelen(patch, size);
1906                 int plen, added;
1907                 int added_blank_line = 0;
1908
1909                 if (!len)
1910                         break;
1911
1912                 /*
1913                  * "plen" is how much of the line we should use for
1914                  * the actual patch data. Normally we just remove the
1915                  * first character on the line, but if the line is
1916                  * followed by "\ No newline", then we also remove the
1917                  * last one (which is the newline, of course).
1918                  */
1919                 plen = len - 1;
1920                 if (len < size && patch[len] == '\\')
1921                         plen--;
1922                 first = *patch;
1923                 if (apply_in_reverse) {
1924                         if (first == '-')
1925                                 first = '+';
1926                         else if (first == '+')
1927                                 first = '-';
1928                 }
1929
1930                 switch (first) {
1931                 case '\n':
1932                         /* Newer GNU diff, empty context line */
1933                         if (plen < 0)
1934                                 /* ... followed by '\No newline'; nothing */
1935                                 break;
1936                         *old++ = '\n';
1937                         *new++ = '\n';
1938                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
1939                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
1940                         break;
1941                 case ' ':
1942                 case '-':
1943                         memcpy(old, patch + 1, plen);
1944                         add_line_info(&preimage, old, plen,
1945                                       (first == ' ' ? LINE_COMMON : 0));
1946                         old += plen;
1947                         if (first == '-')
1948                                 break;
1949                 /* Fall-through for ' ' */
1950                 case '+':
1951                         /* --no-add does not add new lines */
1952                         if (first == '+' && no_add)
1953                                 break;
1954
1955                         if (first != '+' ||
1956                             !whitespace_error ||
1957                             ws_error_action != correct_ws_error) {
1958                                 memcpy(new, patch + 1, plen);
1959                                 added = plen;
1960                         }
1961                         else {
1962                                 added = ws_fix_copy(new, patch + 1, plen, ws_rule, &applied_after_fixing_ws);
1963                         }
1964                         add_line_info(&postimage, new, added,
1965                                       (first == '+' ? 0 : LINE_COMMON));
1966                         new += added;
1967                         if (first == '+' &&
1968                             added == 1 && new[-1] == '\n')
1969                                 added_blank_line = 1;
1970                         break;
1971                 case '@': case '\\':
1972                         /* Ignore it, we already handled it */
1973                         break;
1974                 default:
1975                         if (apply_verbosely)
1976                                 error("invalid start of line: '%c'", first);
1977                         return -1;
1978                 }
1979                 if (added_blank_line)
1980                         new_blank_lines_at_end++;
1981                 else
1982                         new_blank_lines_at_end = 0;
1983                 patch += len;
1984                 size -= len;
1985         }
1986         if (inaccurate_eof &&
1987             old > oldlines && old[-1] == '\n' &&
1988             new > newlines && new[-1] == '\n') {
1989                 old--;
1990                 new--;
1991         }
1992
1993         leading = frag->leading;
1994         trailing = frag->trailing;
1995
1996         /*
1997          * A hunk to change lines at the beginning would begin with
1998          * @@ -1,L +N,M @@
1999          * but we need to be careful.  -U0 that inserts before the second
2000          * line also has this pattern.
2001          *
2002          * And a hunk to add to an empty file would begin with
2003          * @@ -0,0 +N,M @@
2004          *
2005          * In other words, a hunk that is (frag->oldpos <= 1) with or
2006          * without leading context must match at the beginning.
2007          */
2008         match_beginning = (!frag->oldpos ||
2009                            (frag->oldpos == 1 && !unidiff_zero));
2010
2011         /*
2012          * A hunk without trailing lines must match at the end.
2013          * However, we simply cannot tell if a hunk must match end
2014          * from the lack of trailing lines if the patch was generated
2015          * with unidiff without any context.
2016          */
2017         match_end = !unidiff_zero && !trailing;
2018
2019         pos = frag->newpos ? (frag->newpos - 1) : 0;
2020         preimage.buf = oldlines;
2021         preimage.len = old - oldlines;
2022         postimage.buf = newlines;
2023         postimage.len = new - newlines;
2024         preimage.line = preimage.line_allocated;
2025         postimage.line = postimage.line_allocated;
2026
2027         for (;;) {
2028
2029                 applied_pos = find_pos(img, &preimage, &postimage, pos,
2030                                        ws_rule, match_beginning, match_end);
2031
2032                 if (applied_pos >= 0)
2033                         break;
2034
2035                 /* Am I at my context limits? */
2036                 if ((leading <= p_context) && (trailing <= p_context))
2037                         break;
2038                 if (match_beginning || match_end) {
2039                         match_beginning = match_end = 0;
2040                         continue;
2041                 }
2042
2043                 /*
2044                  * Reduce the number of context lines; reduce both
2045                  * leading and trailing if they are equal otherwise
2046                  * just reduce the larger context.
2047                  */
2048                 if (leading >= trailing) {
2049                         remove_first_line(&preimage);
2050                         remove_first_line(&postimage);
2051                         pos--;
2052                         leading--;
2053                 }
2054                 if (trailing > leading) {
2055                         remove_last_line(&preimage);
2056                         remove_last_line(&postimage);
2057                         trailing--;
2058                 }
2059         }
2060
2061         if (applied_pos >= 0) {
2062                 if (ws_error_action == correct_ws_error &&
2063                     new_blank_lines_at_end &&
2064                     postimage.nr + applied_pos == img->nr) {
2065                         /*
2066                          * If the patch application adds blank lines
2067                          * at the end, and if the patch applies at the
2068                          * end of the image, remove those added blank
2069                          * lines.
2070                          */
2071                         while (new_blank_lines_at_end--)
2072                                 remove_last_line(&postimage);
2073                 }
2074
2075                 /*
2076                  * Warn if it was necessary to reduce the number
2077                  * of context lines.
2078                  */
2079                 if ((leading != frag->leading) ||
2080                     (trailing != frag->trailing))
2081                         fprintf(stderr, "Context reduced to (%ld/%ld)"
2082                                 " to apply fragment at %d\n",
2083                                 leading, trailing, applied_pos+1);
2084                 update_image(img, applied_pos, &preimage, &postimage);
2085         } else {
2086                 if (apply_verbosely)
2087                         error("while searching for:\n%.*s",
2088                               (int)(old - oldlines), oldlines);
2089         }
2090
2091         free(oldlines);
2092         free(newlines);
2093         free(preimage.line_allocated);
2094         free(postimage.line_allocated);
2095
2096         return (applied_pos < 0);
2097 }
2098
2099 static int apply_binary_fragment(struct image *img, struct patch *patch)
2100 {
2101         struct fragment *fragment = patch->fragments;
2102         unsigned long len;
2103         void *dst;
2104
2105         /* Binary patch is irreversible without the optional second hunk */
2106         if (apply_in_reverse) {
2107                 if (!fragment->next)
2108                         return error("cannot reverse-apply a binary patch "
2109                                      "without the reverse hunk to '%s'",
2110                                      patch->new_name
2111                                      ? patch->new_name : patch->old_name);
2112                 fragment = fragment->next;
2113         }
2114         switch (fragment->binary_patch_method) {
2115         case BINARY_DELTA_DEFLATED:
2116                 dst = patch_delta(img->buf, img->len, fragment->patch,
2117                                   fragment->size, &len);
2118                 if (!dst)
2119                         return -1;
2120                 clear_image(img);
2121                 img->buf = dst;
2122                 img->len = len;
2123                 return 0;
2124         case BINARY_LITERAL_DEFLATED:
2125                 clear_image(img);
2126                 img->len = fragment->size;
2127                 img->buf = xmalloc(img->len+1);
2128                 memcpy(img->buf, fragment->patch, img->len);
2129                 img->buf[img->len] = '\0';
2130                 return 0;
2131         }
2132         return -1;
2133 }
2134
2135 static int apply_binary(struct image *img, struct patch *patch)
2136 {
2137         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2138         unsigned char sha1[20];
2139
2140         /*
2141          * For safety, we require patch index line to contain
2142          * full 40-byte textual SHA1 for old and new, at least for now.
2143          */
2144         if (strlen(patch->old_sha1_prefix) != 40 ||
2145             strlen(patch->new_sha1_prefix) != 40 ||
2146             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
2147             get_sha1_hex(patch->new_sha1_prefix, sha1))
2148                 return error("cannot apply binary patch to '%s' "
2149                              "without full index line", name);
2150
2151         if (patch->old_name) {
2152                 /*
2153                  * See if the old one matches what the patch
2154                  * applies to.
2155                  */
2156                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2157                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
2158                         return error("the patch applies to '%s' (%s), "
2159                                      "which does not match the "
2160                                      "current contents.",
2161                                      name, sha1_to_hex(sha1));
2162         }
2163         else {
2164                 /* Otherwise, the old one must be empty. */
2165                 if (img->len)
2166                         return error("the patch applies to an empty "
2167                                      "'%s' but it is not empty", name);
2168         }
2169
2170         get_sha1_hex(patch->new_sha1_prefix, sha1);
2171         if (is_null_sha1(sha1)) {
2172                 clear_image(img);
2173                 return 0; /* deletion patch */
2174         }
2175
2176         if (has_sha1_file(sha1)) {
2177                 /* We already have the postimage */
2178                 enum object_type type;
2179                 unsigned long size;
2180                 char *result;
2181
2182                 result = read_sha1_file(sha1, &type, &size);
2183                 if (!result)
2184                         return error("the necessary postimage %s for "
2185                                      "'%s' cannot be read",
2186                                      patch->new_sha1_prefix, name);
2187                 clear_image(img);
2188                 img->buf = result;
2189                 img->len = size;
2190         } else {
2191                 /*
2192                  * We have verified buf matches the preimage;
2193                  * apply the patch data to it, which is stored
2194                  * in the patch->fragments->{patch,size}.
2195                  */
2196                 if (apply_binary_fragment(img, patch))
2197                         return error("binary patch does not apply to '%s'",
2198                                      name);
2199
2200                 /* verify that the result matches */
2201                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2202                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
2203                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)",
2204                                 name, patch->new_sha1_prefix, sha1_to_hex(sha1));
2205         }
2206
2207         return 0;
2208 }
2209
2210 static int apply_fragments(struct image *img, struct patch *patch)
2211 {
2212         struct fragment *frag = patch->fragments;
2213         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2214         unsigned ws_rule = patch->ws_rule;
2215         unsigned inaccurate_eof = patch->inaccurate_eof;
2216
2217         if (patch->is_binary)
2218                 return apply_binary(img, patch);
2219
2220         while (frag) {
2221                 if (apply_one_fragment(img, frag, inaccurate_eof, ws_rule)) {
2222                         error("patch failed: %s:%ld", name, frag->oldpos);
2223                         if (!apply_with_reject)
2224                                 return -1;
2225                         frag->rejected = 1;
2226                 }
2227                 frag = frag->next;
2228         }
2229         return 0;
2230 }
2231
2232 static int read_file_or_gitlink(struct cache_entry *ce, struct strbuf *buf)
2233 {
2234         if (!ce)
2235                 return 0;
2236
2237         if (S_ISGITLINK(ce->ce_mode)) {
2238                 strbuf_grow(buf, 100);
2239                 strbuf_addf(buf, "Subproject commit %s\n", sha1_to_hex(ce->sha1));
2240         } else {
2241                 enum object_type type;
2242                 unsigned long sz;
2243                 char *result;
2244
2245                 result = read_sha1_file(ce->sha1, &type, &sz);
2246                 if (!result)
2247                         return -1;
2248                 /* XXX read_sha1_file NUL-terminates */
2249                 strbuf_attach(buf, result, sz, sz + 1);
2250         }
2251         return 0;
2252 }
2253
2254 static struct patch *in_fn_table(const char *name)
2255 {
2256         struct string_list_item *item;
2257
2258         if (name == NULL)
2259                 return NULL;
2260
2261         item = string_list_lookup(name, &fn_table);
2262         if (item != NULL)
2263                 return (struct patch *)item->util;
2264
2265         return NULL;
2266 }
2267
2268 static void add_to_fn_table(struct patch *patch)
2269 {
2270         struct string_list_item *item;
2271
2272         /*
2273          * Always add new_name unless patch is a deletion
2274          * This should cover the cases for normal diffs,
2275          * file creations and copies
2276          */
2277         if (patch->new_name != NULL) {
2278                 item = string_list_insert(patch->new_name, &fn_table);
2279                 item->util = patch;
2280         }
2281
2282         /*
2283          * store a failure on rename/deletion cases because
2284          * later chunks shouldn't patch old names
2285          */
2286         if ((patch->new_name == NULL) || (patch->is_rename)) {
2287                 item = string_list_insert(patch->old_name, &fn_table);
2288                 item->util = (struct patch *) -1;
2289         }
2290 }
2291
2292 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
2293 {
2294         struct strbuf buf = STRBUF_INIT;
2295         struct image image;
2296         size_t len;
2297         char *img;
2298         struct patch *tpatch;
2299
2300         if (!(patch->is_copy || patch->is_rename) &&
2301             ((tpatch = in_fn_table(patch->old_name)) != NULL)) {
2302                 if (tpatch == (struct patch *) -1) {
2303                         return error("patch %s has been renamed/deleted",
2304                                 patch->old_name);
2305                 }
2306                 /* We have a patched copy in memory use that */
2307                 strbuf_add(&buf, tpatch->result, tpatch->resultsize);
2308         } else if (cached) {
2309                 if (read_file_or_gitlink(ce, &buf))
2310                         return error("read of %s failed", patch->old_name);
2311         } else if (patch->old_name) {
2312                 if (S_ISGITLINK(patch->old_mode)) {
2313                         if (ce) {
2314                                 read_file_or_gitlink(ce, &buf);
2315                         } else {
2316                                 /*
2317                                  * There is no way to apply subproject
2318                                  * patch without looking at the index.
2319                                  */
2320                                 patch->fragments = NULL;
2321                         }
2322                 } else {
2323                         if (read_old_data(st, patch->old_name, &buf))
2324                                 return error("read of %s failed", patch->old_name);
2325                 }
2326         }
2327
2328         img = strbuf_detach(&buf, &len);
2329         prepare_image(&image, img, len, !patch->is_binary);
2330
2331         if (apply_fragments(&image, patch) < 0)
2332                 return -1; /* note with --reject this succeeds. */
2333         patch->result = image.buf;
2334         patch->resultsize = image.len;
2335         add_to_fn_table(patch);
2336         free(image.line_allocated);
2337
2338         if (0 < patch->is_delete && patch->resultsize)
2339                 return error("removal patch leaves file contents");
2340
2341         return 0;
2342 }
2343
2344 static int check_to_create_blob(const char *new_name, int ok_if_exists)
2345 {
2346         struct stat nst;
2347         if (!lstat(new_name, &nst)) {
2348                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2349                         return 0;
2350                 /*
2351                  * A leading component of new_name might be a symlink
2352                  * that is going to be removed with this patch, but
2353                  * still pointing at somewhere that has the path.
2354                  * In such a case, path "new_name" does not exist as
2355                  * far as git is concerned.
2356                  */
2357                 if (has_symlink_leading_path(strlen(new_name), new_name))
2358                         return 0;
2359
2360                 return error("%s: already exists in working directory", new_name);
2361         }
2362         else if ((errno != ENOENT) && (errno != ENOTDIR))
2363                 return error("%s: %s", new_name, strerror(errno));
2364         return 0;
2365 }
2366
2367 static int verify_index_match(struct cache_entry *ce, struct stat *st)
2368 {
2369         if (S_ISGITLINK(ce->ce_mode)) {
2370                 if (!S_ISDIR(st->st_mode))
2371                         return -1;
2372                 return 0;
2373         }
2374         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID);
2375 }
2376
2377 static int check_preimage(struct patch *patch, struct cache_entry **ce, struct stat *st)
2378 {
2379         const char *old_name = patch->old_name;
2380         struct patch *tpatch = NULL;
2381         int stat_ret = 0;
2382         unsigned st_mode = 0;
2383
2384         /*
2385          * Make sure that we do not have local modifications from the
2386          * index when we are looking at the index.  Also make sure
2387          * we have the preimage file to be patched in the work tree,
2388          * unless --cached, which tells git to apply only in the index.
2389          */
2390         if (!old_name)
2391                 return 0;
2392
2393         assert(patch->is_new <= 0);
2394
2395         if (!(patch->is_copy || patch->is_rename) &&
2396             (tpatch = in_fn_table(old_name)) != NULL) {
2397                 if (tpatch == (struct patch *) -1) {
2398                         return error("%s: has been deleted/renamed", old_name);
2399                 }
2400                 st_mode = tpatch->new_mode;
2401         } else if (!cached) {
2402                 stat_ret = lstat(old_name, st);
2403                 if (stat_ret && errno != ENOENT)
2404                         return error("%s: %s", old_name, strerror(errno));
2405         }
2406
2407         if (check_index && !tpatch) {
2408                 int pos = cache_name_pos(old_name, strlen(old_name));
2409                 if (pos < 0) {
2410                         if (patch->is_new < 0)
2411                                 goto is_new;
2412                         return error("%s: does not exist in index", old_name);
2413                 }
2414                 *ce = active_cache[pos];
2415                 if (stat_ret < 0) {
2416                         struct checkout costate;
2417                         /* checkout */
2418                         costate.base_dir = "";
2419                         costate.base_dir_len = 0;
2420                         costate.force = 0;
2421                         costate.quiet = 0;
2422                         costate.not_new = 0;
2423                         costate.refresh_cache = 1;
2424                         if (checkout_entry(*ce, &costate, NULL) ||
2425                             lstat(old_name, st))
2426                                 return -1;
2427                 }
2428                 if (!cached && verify_index_match(*ce, st))
2429                         return error("%s: does not match index", old_name);
2430                 if (cached)
2431                         st_mode = (*ce)->ce_mode;
2432         } else if (stat_ret < 0) {
2433                 if (patch->is_new < 0)
2434                         goto is_new;
2435                 return error("%s: %s", old_name, strerror(errno));
2436         }
2437
2438         if (!cached)
2439                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
2440
2441         if (patch->is_new < 0)
2442                 patch->is_new = 0;
2443         if (!patch->old_mode)
2444                 patch->old_mode = st_mode;
2445         if ((st_mode ^ patch->old_mode) & S_IFMT)
2446                 return error("%s: wrong type", old_name);
2447         if (st_mode != patch->old_mode)
2448                 fprintf(stderr, "warning: %s has type %o, expected %o\n",
2449                         old_name, st_mode, patch->old_mode);
2450         if (!patch->new_mode)
2451                 patch->new_mode = st_mode;
2452         return 0;
2453
2454  is_new:
2455         patch->is_new = 1;
2456         patch->is_delete = 0;
2457         patch->old_name = NULL;
2458         return 0;
2459 }
2460
2461 static int check_patch(struct patch *patch)
2462 {
2463         struct stat st;
2464         const char *old_name = patch->old_name;
2465         const char *new_name = patch->new_name;
2466         const char *name = old_name ? old_name : new_name;
2467         struct cache_entry *ce = NULL;
2468         int ok_if_exists;
2469         int status;
2470
2471         patch->rejected = 1; /* we will drop this after we succeed */
2472
2473         status = check_preimage(patch, &ce, &st);
2474         if (status)
2475                 return status;
2476         old_name = patch->old_name;
2477
2478         if (in_fn_table(new_name) == (struct patch *) -1)
2479                 /*
2480                  * A type-change diff is always split into a patch to
2481                  * delete old, immediately followed by a patch to
2482                  * create new (see diff.c::run_diff()); in such a case
2483                  * it is Ok that the entry to be deleted by the
2484                  * previous patch is still in the working tree and in
2485                  * the index.
2486                  */
2487                 ok_if_exists = 1;
2488         else
2489                 ok_if_exists = 0;
2490
2491         if (new_name &&
2492             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2493                 if (check_index &&
2494                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2495                     !ok_if_exists)
2496                         return error("%s: already exists in index", new_name);
2497                 if (!cached) {
2498                         int err = check_to_create_blob(new_name, ok_if_exists);
2499                         if (err)
2500                                 return err;
2501                 }
2502                 if (!patch->new_mode) {
2503                         if (0 < patch->is_new)
2504                                 patch->new_mode = S_IFREG | 0644;
2505                         else
2506                                 patch->new_mode = patch->old_mode;
2507                 }
2508         }
2509
2510         if (new_name && old_name) {
2511                 int same = !strcmp(old_name, new_name);
2512                 if (!patch->new_mode)
2513                         patch->new_mode = patch->old_mode;
2514                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2515                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2516                                 patch->new_mode, new_name, patch->old_mode,
2517                                 same ? "" : " of ", same ? "" : old_name);
2518         }
2519
2520         if (apply_data(patch, &st, ce) < 0)
2521                 return error("%s: patch does not apply", name);
2522         patch->rejected = 0;
2523         return 0;
2524 }
2525
2526 static int check_patch_list(struct patch *patch)
2527 {
2528         int err = 0;
2529
2530         while (patch) {
2531                 if (apply_verbosely)
2532                         say_patch_name(stderr,
2533                                        "Checking patch ", patch, "...\n");
2534                 err |= check_patch(patch);
2535                 patch = patch->next;
2536         }
2537         return err;
2538 }
2539
2540 /* This function tries to read the sha1 from the current index */
2541 static int get_current_sha1(const char *path, unsigned char *sha1)
2542 {
2543         int pos;
2544
2545         if (read_cache() < 0)
2546                 return -1;
2547         pos = cache_name_pos(path, strlen(path));
2548         if (pos < 0)
2549                 return -1;
2550         hashcpy(sha1, active_cache[pos]->sha1);
2551         return 0;
2552 }
2553
2554 /* Build an index that contains the just the files needed for a 3way merge */
2555 static void build_fake_ancestor(struct patch *list, const char *filename)
2556 {
2557         struct patch *patch;
2558         struct index_state result = { 0 };
2559         int fd;
2560
2561         /* Once we start supporting the reverse patch, it may be
2562          * worth showing the new sha1 prefix, but until then...
2563          */
2564         for (patch = list; patch; patch = patch->next) {
2565                 const unsigned char *sha1_ptr;
2566                 unsigned char sha1[20];
2567                 struct cache_entry *ce;
2568                 const char *name;
2569
2570                 name = patch->old_name ? patch->old_name : patch->new_name;
2571                 if (0 < patch->is_new)
2572                         continue;
2573                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2574                         /* git diff has no index line for mode/type changes */
2575                         if (!patch->lines_added && !patch->lines_deleted) {
2576                                 if (get_current_sha1(patch->new_name, sha1) ||
2577                                     get_current_sha1(patch->old_name, sha1))
2578                                         die("mode change for %s, which is not "
2579                                                 "in current HEAD", name);
2580                                 sha1_ptr = sha1;
2581                         } else
2582                                 die("sha1 information is lacking or useless "
2583                                         "(%s).", name);
2584                 else
2585                         sha1_ptr = sha1;
2586
2587                 ce = make_cache_entry(patch->old_mode, sha1_ptr, name, 0, 0);
2588                 if (!ce)
2589                         die("make_cache_entry failed for path '%s'", name);
2590                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD))
2591                         die ("Could not add %s to temporary index", name);
2592         }
2593
2594         fd = open(filename, O_WRONLY | O_CREAT, 0666);
2595         if (fd < 0 || write_index(&result, fd) || close(fd))
2596                 die ("Could not write temporary index to %s", filename);
2597
2598         discard_index(&result);
2599 }
2600
2601 static void stat_patch_list(struct patch *patch)
2602 {
2603         int files, adds, dels;
2604
2605         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2606                 files++;
2607                 adds += patch->lines_added;
2608                 dels += patch->lines_deleted;
2609                 show_stats(patch);
2610         }
2611
2612         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2613 }
2614
2615 static void numstat_patch_list(struct patch *patch)
2616 {
2617         for ( ; patch; patch = patch->next) {
2618                 const char *name;
2619                 name = patch->new_name ? patch->new_name : patch->old_name;
2620                 if (patch->is_binary)
2621                         printf("-\t-\t");
2622                 else
2623                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
2624                 write_name_quoted(name, stdout, line_termination);
2625         }
2626 }
2627
2628 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2629 {
2630         if (mode)
2631                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2632         else
2633                 printf(" %s %s\n", newdelete, name);
2634 }
2635
2636 static void show_mode_change(struct patch *p, int show_name)
2637 {
2638         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2639                 if (show_name)
2640                         printf(" mode change %06o => %06o %s\n",
2641                                p->old_mode, p->new_mode, p->new_name);
2642                 else
2643                         printf(" mode change %06o => %06o\n",
2644                                p->old_mode, p->new_mode);
2645         }
2646 }
2647
2648 static void show_rename_copy(struct patch *p)
2649 {
2650         const char *renamecopy = p->is_rename ? "rename" : "copy";
2651         const char *old, *new;
2652
2653         /* Find common prefix */
2654         old = p->old_name;
2655         new = p->new_name;
2656         while (1) {
2657                 const char *slash_old, *slash_new;
2658                 slash_old = strchr(old, '/');
2659                 slash_new = strchr(new, '/');
2660                 if (!slash_old ||
2661                     !slash_new ||
2662                     slash_old - old != slash_new - new ||
2663                     memcmp(old, new, slash_new - new))
2664                         break;
2665                 old = slash_old + 1;
2666                 new = slash_new + 1;
2667         }
2668         /* p->old_name thru old is the common prefix, and old and new
2669          * through the end of names are renames
2670          */
2671         if (old != p->old_name)
2672                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2673                        (int)(old - p->old_name), p->old_name,
2674                        old, new, p->score);
2675         else
2676                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2677                        p->old_name, p->new_name, p->score);
2678         show_mode_change(p, 0);
2679 }
2680
2681 static void summary_patch_list(struct patch *patch)
2682 {
2683         struct patch *p;
2684
2685         for (p = patch; p; p = p->next) {
2686                 if (p->is_new)
2687                         show_file_mode_name("create", p->new_mode, p->new_name);
2688                 else if (p->is_delete)
2689                         show_file_mode_name("delete", p->old_mode, p->old_name);
2690                 else {
2691                         if (p->is_rename || p->is_copy)
2692                                 show_rename_copy(p);
2693                         else {
2694                                 if (p->score) {
2695                                         printf(" rewrite %s (%d%%)\n",
2696                                                p->new_name, p->score);
2697                                         show_mode_change(p, 0);
2698                                 }
2699                                 else
2700                                         show_mode_change(p, 1);
2701                         }
2702                 }
2703         }
2704 }
2705
2706 static void patch_stats(struct patch *patch)
2707 {
2708         int lines = patch->lines_added + patch->lines_deleted;
2709
2710         if (lines > max_change)
2711                 max_change = lines;
2712         if (patch->old_name) {
2713                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2714                 if (!len)
2715                         len = strlen(patch->old_name);
2716                 if (len > max_len)
2717                         max_len = len;
2718         }
2719         if (patch->new_name) {
2720                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2721                 if (!len)
2722                         len = strlen(patch->new_name);
2723                 if (len > max_len)
2724                         max_len = len;
2725         }
2726 }
2727
2728 static void remove_file(struct patch *patch, int rmdir_empty)
2729 {
2730         if (update_index) {
2731                 if (remove_file_from_cache(patch->old_name) < 0)
2732                         die("unable to remove %s from index", patch->old_name);
2733         }
2734         if (!cached) {
2735                 if (S_ISGITLINK(patch->old_mode)) {
2736                         if (rmdir(patch->old_name))
2737                                 warning("unable to remove submodule %s",
2738                                         patch->old_name);
2739                 } else if (!unlink(patch->old_name) && rmdir_empty) {
2740                         remove_path(patch->old_name);
2741                 }
2742         }
2743 }
2744
2745 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2746 {
2747         struct stat st;
2748         struct cache_entry *ce;
2749         int namelen = strlen(path);
2750         unsigned ce_size = cache_entry_size(namelen);
2751
2752         if (!update_index)
2753                 return;
2754
2755         ce = xcalloc(1, ce_size);
2756         memcpy(ce->name, path, namelen);
2757         ce->ce_mode = create_ce_mode(mode);
2758         ce->ce_flags = namelen;
2759         if (S_ISGITLINK(mode)) {
2760                 const char *s = buf;
2761
2762                 if (get_sha1_hex(s + strlen("Subproject commit "), ce->sha1))
2763                         die("corrupt patch for subproject %s", path);
2764         } else {
2765                 if (!cached) {
2766                         if (lstat(path, &st) < 0)
2767                                 die("unable to stat newly created file %s",
2768                                     path);
2769                         fill_stat_cache_info(ce, &st);
2770                 }
2771                 if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2772                         die("unable to create backing store for newly created file %s", path);
2773         }
2774         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2775                 die("unable to add cache entry for %s", path);
2776 }
2777
2778 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2779 {
2780         int fd;
2781         struct strbuf nbuf = STRBUF_INIT;
2782
2783         if (S_ISGITLINK(mode)) {
2784                 struct stat st;
2785                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
2786                         return 0;
2787                 return mkdir(path, 0777);
2788         }
2789
2790         if (has_symlinks && S_ISLNK(mode))
2791                 /* Although buf:size is counted string, it also is NUL
2792                  * terminated.
2793                  */
2794                 return symlink(buf, path);
2795
2796         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2797         if (fd < 0)
2798                 return -1;
2799
2800         if (convert_to_working_tree(path, buf, size, &nbuf)) {
2801                 size = nbuf.len;
2802                 buf  = nbuf.buf;
2803         }
2804         write_or_die(fd, buf, size);
2805         strbuf_release(&nbuf);
2806
2807         if (close(fd) < 0)
2808                 die("closing file %s: %s", path, strerror(errno));
2809         return 0;
2810 }
2811
2812 /*
2813  * We optimistically assume that the directories exist,
2814  * which is true 99% of the time anyway. If they don't,
2815  * we create them and try again.
2816  */
2817 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2818 {
2819         if (cached)
2820                 return;
2821         if (!try_create_file(path, mode, buf, size))
2822                 return;
2823
2824         if (errno == ENOENT) {
2825                 if (safe_create_leading_directories(path))
2826                         return;
2827                 if (!try_create_file(path, mode, buf, size))
2828                         return;
2829         }
2830
2831         if (errno == EEXIST || errno == EACCES) {
2832                 /* We may be trying to create a file where a directory
2833                  * used to be.
2834                  */
2835                 struct stat st;
2836                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
2837                         errno = EEXIST;
2838         }
2839
2840         if (errno == EEXIST) {
2841                 unsigned int nr = getpid();
2842
2843                 for (;;) {
2844                         char newpath[PATH_MAX];
2845                         mksnpath(newpath, sizeof(newpath), "%s~%u", path, nr);
2846                         if (!try_create_file(newpath, mode, buf, size)) {
2847                                 if (!rename(newpath, path))
2848                                         return;
2849                                 unlink(newpath);
2850                                 break;
2851                         }
2852                         if (errno != EEXIST)
2853                                 break;
2854                         ++nr;
2855                 }
2856         }
2857         die("unable to write file %s mode %o", path, mode);
2858 }
2859
2860 static void create_file(struct patch *patch)
2861 {
2862         char *path = patch->new_name;
2863         unsigned mode = patch->new_mode;
2864         unsigned long size = patch->resultsize;
2865         char *buf = patch->result;
2866
2867         if (!mode)
2868                 mode = S_IFREG | 0644;
2869         create_one_file(path, mode, buf, size);
2870         add_index_file(path, mode, buf, size);
2871 }
2872
2873 /* phase zero is to remove, phase one is to create */
2874 static void write_out_one_result(struct patch *patch, int phase)
2875 {
2876         if (patch->is_delete > 0) {
2877                 if (phase == 0)
2878                         remove_file(patch, 1);
2879                 return;
2880         }
2881         if (patch->is_new > 0 || patch->is_copy) {
2882                 if (phase == 1)
2883                         create_file(patch);
2884                 return;
2885         }
2886         /*
2887          * Rename or modification boils down to the same
2888          * thing: remove the old, write the new
2889          */
2890         if (phase == 0)
2891                 remove_file(patch, patch->is_rename);
2892         if (phase == 1)
2893                 create_file(patch);
2894 }
2895
2896 static int write_out_one_reject(struct patch *patch)
2897 {
2898         FILE *rej;
2899         char namebuf[PATH_MAX];
2900         struct fragment *frag;
2901         int cnt = 0;
2902
2903         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2904                 if (!frag->rejected)
2905                         continue;
2906                 cnt++;
2907         }
2908
2909         if (!cnt) {
2910                 if (apply_verbosely)
2911                         say_patch_name(stderr,
2912                                        "Applied patch ", patch, " cleanly.\n");
2913                 return 0;
2914         }
2915
2916         /* This should not happen, because a removal patch that leaves
2917          * contents are marked "rejected" at the patch level.
2918          */
2919         if (!patch->new_name)
2920                 die("internal error");
2921
2922         /* Say this even without --verbose */
2923         say_patch_name(stderr, "Applying patch ", patch, " with");
2924         fprintf(stderr, " %d rejects...\n", cnt);
2925
2926         cnt = strlen(patch->new_name);
2927         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2928                 cnt = ARRAY_SIZE(namebuf) - 5;
2929                 fprintf(stderr,
2930                         "warning: truncating .rej filename to %.*s.rej",
2931                         cnt - 1, patch->new_name);
2932         }
2933         memcpy(namebuf, patch->new_name, cnt);
2934         memcpy(namebuf + cnt, ".rej", 5);
2935
2936         rej = fopen(namebuf, "w");
2937         if (!rej)
2938                 return error("cannot open %s: %s", namebuf, strerror(errno));
2939
2940         /* Normal git tools never deal with .rej, so do not pretend
2941          * this is a git patch by saying --git nor give extended
2942          * headers.  While at it, maybe please "kompare" that wants
2943          * the trailing TAB and some garbage at the end of line ;-).
2944          */
2945         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2946                 patch->new_name, patch->new_name);
2947         for (cnt = 1, frag = patch->fragments;
2948              frag;
2949              cnt++, frag = frag->next) {
2950                 if (!frag->rejected) {
2951                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2952                         continue;
2953                 }
2954                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2955                 fprintf(rej, "%.*s", frag->size, frag->patch);
2956                 if (frag->patch[frag->size-1] != '\n')
2957                         fputc('\n', rej);
2958         }
2959         fclose(rej);
2960         return -1;
2961 }
2962
2963 static int write_out_results(struct patch *list, int skipped_patch)
2964 {
2965         int phase;
2966         int errs = 0;
2967         struct patch *l;
2968
2969         if (!list && !skipped_patch)
2970                 return error("No changes");
2971
2972         for (phase = 0; phase < 2; phase++) {
2973                 l = list;
2974                 while (l) {
2975                         if (l->rejected)
2976                                 errs = 1;
2977                         else {
2978                                 write_out_one_result(l, phase);
2979                                 if (phase == 1 && write_out_one_reject(l))
2980                                         errs = 1;
2981                         }
2982                         l = l->next;
2983                 }
2984         }
2985         return errs;
2986 }
2987
2988 static struct lock_file lock_file;
2989
2990 static struct string_list limit_by_name;
2991 static int has_include;
2992 static void add_name_limit(const char *name, int exclude)
2993 {
2994         struct string_list_item *it;
2995
2996         it = string_list_append(name, &limit_by_name);
2997         it->util = exclude ? NULL : (void *) 1;
2998 }
2999
3000 static int use_patch(struct patch *p)
3001 {
3002         const char *pathname = p->new_name ? p->new_name : p->old_name;
3003         int i;
3004
3005         /* Paths outside are not touched regardless of "--include" */
3006         if (0 < prefix_length) {
3007                 int pathlen = strlen(pathname);
3008                 if (pathlen <= prefix_length ||
3009                     memcmp(prefix, pathname, prefix_length))
3010                         return 0;
3011         }
3012
3013         /* See if it matches any of exclude/include rule */
3014         for (i = 0; i < limit_by_name.nr; i++) {
3015                 struct string_list_item *it = &limit_by_name.items[i];
3016                 if (!fnmatch(it->string, pathname, 0))
3017                         return (it->util != NULL);
3018         }
3019
3020         /*
3021          * If we had any include, a path that does not match any rule is
3022          * not used.  Otherwise, we saw bunch of exclude rules (or none)
3023          * and such a path is used.
3024          */
3025         return !has_include;
3026 }
3027
3028
3029 static void prefix_one(char **name)
3030 {
3031         char *old_name = *name;
3032         if (!old_name)
3033                 return;
3034         *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
3035         free(old_name);
3036 }
3037
3038 static void prefix_patches(struct patch *p)
3039 {
3040         if (!prefix || p->is_toplevel_relative)
3041                 return;
3042         for ( ; p; p = p->next) {
3043                 if (p->new_name == p->old_name) {
3044                         char *prefixed = p->new_name;
3045                         prefix_one(&prefixed);
3046                         p->new_name = p->old_name = prefixed;
3047                 }
3048                 else {
3049                         prefix_one(&p->new_name);
3050                         prefix_one(&p->old_name);
3051                 }
3052         }
3053 }
3054
3055 #define INACCURATE_EOF  (1<<0)
3056 #define RECOUNT         (1<<1)
3057
3058 static int apply_patch(int fd, const char *filename, int options)
3059 {
3060         size_t offset;
3061         struct strbuf buf = STRBUF_INIT;
3062         struct patch *list = NULL, **listp = &list;
3063         int skipped_patch = 0;
3064
3065         /* FIXME - memory leak when using multiple patch files as inputs */
3066         memset(&fn_table, 0, sizeof(struct string_list));
3067         patch_input_file = filename;
3068         read_patch_file(&buf, fd);
3069         offset = 0;
3070         while (offset < buf.len) {
3071                 struct patch *patch;
3072                 int nr;
3073
3074                 patch = xcalloc(1, sizeof(*patch));
3075                 patch->inaccurate_eof = !!(options & INACCURATE_EOF);
3076                 patch->recount =  !!(options & RECOUNT);
3077                 nr = parse_chunk(buf.buf + offset, buf.len - offset, patch);
3078                 if (nr < 0)
3079                         break;
3080                 if (apply_in_reverse)
3081                         reverse_patches(patch);
3082                 if (prefix)
3083                         prefix_patches(patch);
3084                 if (use_patch(patch)) {
3085                         patch_stats(patch);
3086                         *listp = patch;
3087                         listp = &patch->next;
3088                 }
3089                 else {
3090                         /* perhaps free it a bit better? */
3091                         free(patch);
3092                         skipped_patch++;
3093                 }
3094                 offset += nr;
3095         }
3096
3097         if (whitespace_error && (ws_error_action == die_on_ws_error))
3098                 apply = 0;
3099
3100         update_index = check_index && apply;
3101         if (update_index && newfd < 0)
3102                 newfd = hold_locked_index(&lock_file, 1);
3103
3104         if (check_index) {
3105                 if (read_cache() < 0)
3106                         die("unable to read index file");
3107         }
3108
3109         if ((check || apply) &&
3110             check_patch_list(list) < 0 &&
3111             !apply_with_reject)
3112                 exit(1);
3113
3114         if (apply && write_out_results(list, skipped_patch))
3115                 exit(1);
3116
3117         if (fake_ancestor)
3118                 build_fake_ancestor(list, fake_ancestor);
3119
3120         if (diffstat)
3121                 stat_patch_list(list);
3122
3123         if (numstat)
3124                 numstat_patch_list(list);
3125
3126         if (summary)
3127                 summary_patch_list(list);
3128
3129         strbuf_release(&buf);
3130         return 0;
3131 }
3132
3133 static int git_apply_config(const char *var, const char *value, void *cb)
3134 {
3135         if (!strcmp(var, "apply.whitespace"))
3136                 return git_config_string(&apply_default_whitespace, var, value);
3137         return git_default_config(var, value, cb);
3138 }
3139
3140
3141 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
3142 {
3143         int i;
3144         int read_stdin = 1;
3145         int options = 0;
3146         int errs = 0;
3147         int is_not_gitdir;
3148
3149         const char *whitespace_option = NULL;
3150
3151         prefix = setup_git_directory_gently(&is_not_gitdir);
3152         prefix_length = prefix ? strlen(prefix) : 0;
3153         git_config(git_apply_config, NULL);
3154         if (apply_default_whitespace)
3155                 parse_whitespace_option(apply_default_whitespace);
3156
3157         for (i = 1; i < argc; i++) {
3158                 const char *arg = argv[i];
3159                 char *end;
3160                 int fd;
3161
3162                 if (!strcmp(arg, "-")) {
3163                         errs |= apply_patch(0, "<stdin>", options);
3164                         read_stdin = 0;
3165                         continue;
3166                 }
3167                 if (!prefixcmp(arg, "--exclude=")) {
3168                         add_name_limit(arg + 10, 1);
3169                         continue;
3170                 }
3171                 if (!prefixcmp(arg, "--include=")) {
3172                         add_name_limit(arg + 10, 0);
3173                         has_include = 1;
3174                         continue;
3175                 }
3176                 if (!prefixcmp(arg, "-p")) {
3177                         p_value = atoi(arg + 2);
3178                         p_value_known = 1;
3179                         continue;
3180                 }
3181                 if (!strcmp(arg, "--no-add")) {
3182                         no_add = 1;
3183                         continue;
3184                 }
3185                 if (!strcmp(arg, "--stat")) {
3186                         apply = 0;
3187                         diffstat = 1;
3188                         continue;
3189                 }
3190                 if (!strcmp(arg, "--allow-binary-replacement") ||
3191                     !strcmp(arg, "--binary")) {
3192                         continue; /* now no-op */
3193                 }
3194                 if (!strcmp(arg, "--numstat")) {
3195                         apply = 0;
3196                         numstat = 1;
3197                         continue;
3198                 }
3199                 if (!strcmp(arg, "--summary")) {
3200                         apply = 0;
3201                         summary = 1;
3202                         continue;
3203                 }
3204                 if (!strcmp(arg, "--check")) {
3205                         apply = 0;
3206                         check = 1;
3207                         continue;
3208                 }
3209                 if (!strcmp(arg, "--index")) {
3210                         if (is_not_gitdir)
3211                                 die("--index outside a repository");
3212                         check_index = 1;
3213                         continue;
3214                 }
3215                 if (!strcmp(arg, "--cached")) {
3216                         if (is_not_gitdir)
3217                                 die("--cached outside a repository");
3218                         check_index = 1;
3219                         cached = 1;
3220                         continue;
3221                 }
3222                 if (!strcmp(arg, "--apply")) {
3223                         apply = 1;
3224                         continue;
3225                 }
3226                 if (!strcmp(arg, "--build-fake-ancestor")) {
3227                         apply = 0;
3228                         if (++i >= argc)
3229                                 die ("need a filename");
3230                         fake_ancestor = argv[i];
3231                         continue;
3232                 }
3233                 if (!strcmp(arg, "-z")) {
3234                         line_termination = 0;
3235                         continue;
3236                 }
3237                 if (!prefixcmp(arg, "-C")) {
3238                         p_context = strtoul(arg + 2, &end, 0);
3239                         if (*end != '\0')
3240                                 die("unrecognized context count '%s'", arg + 2);
3241                         continue;
3242                 }
3243                 if (!prefixcmp(arg, "--whitespace=")) {
3244                         whitespace_option = arg + 13;
3245                         parse_whitespace_option(arg + 13);
3246                         continue;
3247                 }
3248                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
3249                         apply_in_reverse = 1;
3250                         continue;
3251                 }
3252                 if (!strcmp(arg, "--unidiff-zero")) {
3253                         unidiff_zero = 1;
3254                         continue;
3255                 }
3256                 if (!strcmp(arg, "--reject")) {
3257                         apply = apply_with_reject = apply_verbosely = 1;
3258                         continue;
3259                 }
3260                 if (!strcmp(arg, "-v") || !strcmp(arg, "--verbose")) {
3261                         apply_verbosely = 1;
3262                         continue;
3263                 }
3264                 if (!strcmp(arg, "--inaccurate-eof")) {
3265                         options |= INACCURATE_EOF;
3266                         continue;
3267                 }
3268                 if (!strcmp(arg, "--recount")) {
3269                         options |= RECOUNT;
3270                         continue;
3271                 }
3272                 if (!prefixcmp(arg, "--directory=")) {
3273                         arg += strlen("--directory=");
3274                         root_len = strlen(arg);
3275                         if (root_len && arg[root_len - 1] != '/') {
3276                                 char *new_root;
3277                                 root = new_root = xmalloc(root_len + 2);
3278                                 strcpy(new_root, arg);
3279                                 strcpy(new_root + root_len++, "/");
3280                         } else
3281                                 root = arg;
3282                         continue;
3283                 }
3284                 if (0 < prefix_length)
3285                         arg = prefix_filename(prefix, prefix_length, arg);
3286
3287                 fd = open(arg, O_RDONLY);
3288                 if (fd < 0)
3289                         die("can't open patch '%s': %s", arg, strerror(errno));
3290                 read_stdin = 0;
3291                 set_default_whitespace_mode(whitespace_option);
3292                 errs |= apply_patch(fd, arg, options);
3293                 close(fd);
3294         }
3295         set_default_whitespace_mode(whitespace_option);
3296         if (read_stdin)
3297                 errs |= apply_patch(0, "<stdin>", options);
3298         if (whitespace_error) {
3299                 if (squelch_whitespace_errors &&
3300                     squelch_whitespace_errors < whitespace_error) {
3301                         int squelched =
3302                                 whitespace_error - squelch_whitespace_errors;
3303                         fprintf(stderr, "warning: squelched %d "
3304                                 "whitespace error%s\n",
3305                                 squelched,
3306                                 squelched == 1 ? "" : "s");
3307                 }
3308                 if (ws_error_action == die_on_ws_error)
3309                         die("%d line%s add%s whitespace errors.",
3310                             whitespace_error,
3311                             whitespace_error == 1 ? "" : "s",
3312                             whitespace_error == 1 ? "s" : "");
3313                 if (applied_after_fixing_ws && apply)
3314                         fprintf(stderr, "warning: %d line%s applied after"
3315                                 " fixing whitespace errors.\n",
3316                                 applied_after_fixing_ws,
3317                                 applied_after_fixing_ws == 1 ? "" : "s");
3318                 else if (whitespace_error)
3319                         fprintf(stderr, "warning: %d line%s add%s whitespace errors.\n",
3320                                 whitespace_error,
3321                                 whitespace_error == 1 ? "" : "s",
3322                                 whitespace_error == 1 ? "s" : "");
3323         }
3324
3325         if (update_index) {
3326                 if (write_cache(newfd, active_cache, active_nr) ||
3327                     commit_locked_index(&lock_file))
3328                         die("Unable to write new index file");
3329         }
3330
3331         return !!errs;
3332 }