builtin-apply.c

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