apply.c

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