builtin-apply.c

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