builtin-apply.c

   1 /*
   2  * apply.c
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  *
   6  * This applies patches on top of some (arbitrary) version of the SCM.
   7  *
   8  */
   9 #include "cache.h"
  10 #include "cache-tree.h"
  11 #include "quote.h"
  12 #include "blob.h"
  13 #include "delta.h"
  14 #include "builtin.h"
  15
  16 /*
  17  *  --check turns on checking that the working tree matches the
  18  *    files that are being modified, but doesn't apply the patch
  19  *  --stat does just a diffstat, and doesn't actually apply
  20  *  --numstat does numeric diffstat, and doesn't actually apply
  21  *  --index-info shows the old and new index info for paths if available.
  22  *  --index updates the cache as well.
  23  *  --cached updates only the cache without ever touching the working tree.
  24  */
  25 static const char *prefix;
  26 static int prefix_length = -1;
  27 static int newfd = -1;
  28
  29 static int unidiff_zero;
  30 static int p_value = 1;
  31 static int p_value_known;
  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 apply_with_reject;
  42 static int apply_verbosely;
  43 static int no_add;
  44 static int show_index_info;
  45 static int line_termination = '\n';
  46 static unsigned long p_context = ULONG_MAX;
  47 static const char apply_usage[] =
  48 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [--verbose] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|error|error-all|strip>] <patch>...";
  49
  50 static enum whitespace_eol {
  51         nowarn_whitespace,
  52         warn_on_whitespace,
  53         error_on_whitespace,
  54         strip_whitespace,
  55 } new_whitespace = warn_on_whitespace;
  56 static int whitespace_error;
  57 static int squelch_whitespace_errors = 5;
  58 static int applied_after_stripping;
  59 static const char *patch_input_file;
  60
  61 static void parse_whitespace_option(const char *option)
  62 {
  63         if (!option) {
  64                 new_whitespace = warn_on_whitespace;
  65                 return;
  66         }
  67         if (!strcmp(option, "warn")) {
  68                 new_whitespace = warn_on_whitespace;
  69                 return;
  70         }
  71         if (!strcmp(option, "nowarn")) {
  72                 new_whitespace = nowarn_whitespace;
  73                 return;
  74         }
  75         if (!strcmp(option, "error")) {
  76                 new_whitespace = error_on_whitespace;
  77                 return;
  78         }
  79         if (!strcmp(option, "error-all")) {
  80                 new_whitespace = error_on_whitespace;
  81                 squelch_whitespace_errors = 0;
  82                 return;
  83         }
  84         if (!strcmp(option, "strip")) {
  85                 new_whitespace = strip_whitespace;
  86                 return;
  87         }
  88         die("unrecognized whitespace option '%s'", option);
  89 }
  90
  91 static void set_default_whitespace_mode(const char *whitespace_option)
  92 {
  93         if (!whitespace_option && !apply_default_whitespace) {
  94                 new_whitespace = (apply
  95                                   ? warn_on_whitespace
  96                                   : nowarn_whitespace);
  97         }
  98 }
  99
 100 /*
 101  * For "diff-stat" like behaviour, we keep track of the biggest change
 102  * we've seen, and the longest filename. That allows us to do simple
 103  * scaling.
 104  */
 105 static int max_change, max_len;
 106
 107 /*
 108  * Various "current state", notably line numbers and what
 109  * file (and how) we're patching right now.. The "is_xxxx"
 110  * things are flags, where -1 means "don't know yet".
 111  */
 112 static int linenr = 1;
 113
 114 /*
 115  * This represents one "hunk" from a patch, starting with
 116  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 117  * patch text is pointed at by patch, and its byte length
 118  * is stored in size.  leading and trailing are the number
 119  * of context lines.
 120  */
 121 struct fragment {
 122         unsigned long leading, trailing;
 123         unsigned long oldpos, oldlines;
 124         unsigned long newpos, newlines;
 125         const char *patch;
 126         int size;
 127         int rejected;
 128         struct fragment *next;
 129 };
 130
 131 /*
 132  * When dealing with a binary patch, we reuse "leading" field
 133  * to store the type of the binary hunk, either deflated "delta"
 134  * or deflated "literal".
 135  */
 136 #define binary_patch_method leading
 137 #define BINARY_DELTA_DEFLATED   1
 138 #define BINARY_LITERAL_DEFLATED 2
 139
 140 struct patch {
 141         char *new_name, *old_name, *def_name;
 142         unsigned int old_mode, new_mode;
 143         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
 144         int rejected;
 145         unsigned long deflate_origlen;
 146         int lines_added, lines_deleted;
 147         int score;
 148         unsigned int is_toplevel_relative:1;
 149         unsigned int inaccurate_eof:1;
 150         unsigned int is_binary:1;
 151         unsigned int is_copy:1;
 152         unsigned int is_rename:1;
 153         struct fragment *fragments;
 154         char *result;
 155         unsigned long resultsize;
 156         char old_sha1_prefix[41];
 157         char new_sha1_prefix[41];
 158         struct patch *next;
 159 };
 160
 161 static void say_patch_name(FILE *output, const char *pre, struct patch *patch, const char *post)
 162 {
 163         fputs(pre, output);
 164         if (patch->old_name && patch->new_name &&
 165             strcmp(patch->old_name, patch->new_name)) {
 166                 write_name_quoted(NULL, 0, patch->old_name, 1, output);
 167                 fputs(" => ", output);
 168                 write_name_quoted(NULL, 0, patch->new_name, 1, output);
 169         }
 170         else {
 171                 const char *n = patch->new_name;
 172                 if (!n)
 173                         n = patch->old_name;
 174                 write_name_quoted(NULL, 0, n, 1, output);
 175         }
 176         fputs(post, output);
 177 }
 178
 179 #define CHUNKSIZE (8192)
 180 #define SLOP (16)
 181
 182 static void *read_patch_file(int fd, unsigned long *sizep)
 183 {
 184         unsigned long size = 0, alloc = CHUNKSIZE;
 185         void *buffer = xmalloc(alloc);
 186
 187         for (;;) {
 188                 int nr = alloc - size;
 189                 if (nr < 1024) {
 190                         alloc += CHUNKSIZE;
 191                         buffer = xrealloc(buffer, alloc);
 192                         nr = alloc - size;
 193                 }
 194                 nr = xread(fd, (char *) buffer + size, nr);
 195                 if (!nr)
 196                         break;
 197                 if (nr < 0)
 198                         die("git-apply: read returned %s", strerror(errno));
 199                 size += nr;
 200         }
 201         *sizep = size;
 202
 203         /*
 204          * Make sure that we have some slop in the buffer
 205          * so that we can do speculative "memcmp" etc, and
 206          * see to it that it is NUL-filled.
 207          */
 208         if (alloc < size + SLOP)
 209                 buffer = xrealloc(buffer, size + SLOP);
 210         memset((char *) buffer + size, 0, SLOP);
 211         return buffer;
 212 }
 213
 214 static unsigned long linelen(const char *buffer, unsigned long size)
 215 {
 216         unsigned long len = 0;
 217         while (size--) {
 218                 len++;
 219                 if (*buffer++ == '\n')
 220                         break;
 221         }
 222         return len;
 223 }
 224
 225 static int is_dev_null(const char *str)
 226 {
 227         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
 228 }
 229
 230 #define TERM_SPACE      1
 231 #define TERM_TAB        2
 232
 233 static int name_terminate(const char *name, int namelen, int c, int terminate)
 234 {
 235         if (c == ' ' && !(terminate & TERM_SPACE))
 236                 return 0;
 237         if (c == '\t' && !(terminate & TERM_TAB))
 238                 return 0;
 239
 240         return 1;
 241 }
 242
 243 static char *find_name(const char *line, char *def, int p_value, int terminate)
 244 {
 245         int len;
 246         const char *start = line;
 247         char *name;
 248
 249         if (*line == '"') {
 250                 /* Proposed "new-style" GNU patch/diff format; see
 251                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
 252                  */
 253                 name = unquote_c_style(line, NULL);
 254                 if (name) {
 255                         char *cp = name;
 256                         while (p_value) {
 257                                 cp = strchr(name, '/');
 258                                 if (!cp)
 259                                         break;
 260                                 cp++;
 261                                 p_value--;
 262                         }
 263                         if (cp) {
 264                                 /* name can later be freed, so we need
 265                                  * to memmove, not just return cp
 266                                  */
 267                                 memmove(name, cp, strlen(cp) + 1);
 268                                 free(def);
 269                                 return name;
 270                         }
 271                         else {
 272                                 free(name);
 273                                 name = NULL;
 274                         }
 275                 }
 276         }
 277
 278         for (;;) {
 279                 char c = *line;
 280
 281                 if (isspace(c)) {
 282                         if (c == '\n')
 283                                 break;
 284                         if (name_terminate(start, line-start, c, terminate))
 285                                 break;
 286                 }
 287                 line++;
 288                 if (c == '/' && !--p_value)
 289                         start = line;
 290         }
 291         if (!start)
 292                 return def;
 293         len = line - start;
 294         if (!len)
 295                 return def;
 296
 297         /*
 298          * Generally we prefer the shorter name, especially
 299          * if the other one is just a variation of that with
 300          * something else tacked on to the end (ie "file.orig"
 301          * or "file~").
 302          */
 303         if (def) {
 304                 int deflen = strlen(def);
 305                 if (deflen < len && !strncmp(start, def, deflen))
 306                         return def;
 307         }
 308
 309         name = xmalloc(len + 1);
 310         memcpy(name, start, len);
 311         name[len] = 0;
 312         free(def);
 313         return name;
 314 }
 315
 316 static int count_slashes(const char *cp)
 317 {
 318         int cnt = 0;
 319         char ch;
 320
 321         while ((ch = *cp++))
 322                 if (ch == '/')
 323                         cnt++;
 324         return cnt;
 325 }
 326
 327 /*
 328  * Given the string after "--- " or "+++ ", guess the appropriate
 329  * p_value for the given patch.
 330  */
 331 static int guess_p_value(const char *nameline)
 332 {
 333         char *name, *cp;
 334         int val = -1;
 335
 336         if (is_dev_null(nameline))
 337                 return -1;
 338         name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
 339         if (!name)
 340                 return -1;
 341         cp = strchr(name, '/');
 342         if (!cp)
 343                 val = 0;
 344         else if (prefix) {
 345                 /*
 346                  * Does it begin with "a/$our-prefix" and such?  Then this is
 347                  * very likely to apply to our directory.
 348                  */
 349                 if (!strncmp(name, prefix, prefix_length))
 350                         val = count_slashes(prefix);
 351                 else {
 352                         cp++;
 353                         if (!strncmp(cp, prefix, prefix_length))
 354                                 val = count_slashes(prefix) + 1;
 355                 }
 356         }
 357         free(name);
 358         return val;
 359 }
 360
 361 /*
 362  * Get the name etc info from the --/+++ lines of a traditional patch header
 363  *
 364  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 365  * files, we can happily check the index for a match, but for creating a
 366  * new file we should try to match whatever "patch" does. I have no idea.
 367  */
 368 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
 369 {
 370         char *name;
 371
 372         first += 4;     /* skip "--- " */
 373         second += 4;    /* skip "+++ " */
 374         if (!p_value_known) {
 375                 int p, q;
 376                 p = guess_p_value(first);
 377                 q = guess_p_value(second);
 378                 if (p < 0) p = q;
 379                 if (0 <= p && p == q) {
 380                         p_value = p;
 381                         p_value_known = 1;
 382                 }
 383         }
 384         if (is_dev_null(first)) {
 385                 patch->is_new = 1;
 386                 patch->is_delete = 0;
 387                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
 388                 patch->new_name = name;
 389         } else if (is_dev_null(second)) {
 390                 patch->is_new = 0;
 391                 patch->is_delete = 1;
 392                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 393                 patch->old_name = name;
 394         } else {
 395                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 396                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
 397                 patch->old_name = patch->new_name = name;
 398         }
 399         if (!name)
 400                 die("unable to find filename in patch at line %d", linenr);
 401 }
 402
 403 static int gitdiff_hdrend(const char *line, struct patch *patch)
 404 {
 405         return -1;
 406 }
 407
 408 /*
 409  * We're anal about diff header consistency, to make
 410  * sure that we don't end up having strange ambiguous
 411  * patches floating around.
 412  *
 413  * As a result, gitdiff_{old|new}name() will check
 414  * their names against any previous information, just
 415  * to make sure..
 416  */
 417 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
 418 {
 419         if (!orig_name && !isnull)
 420                 return find_name(line, NULL, 1, TERM_TAB);
 421
 422         if (orig_name) {
 423                 int len;
 424                 const char *name;
 425                 char *another;
 426                 name = orig_name;
 427                 len = strlen(name);
 428                 if (isnull)
 429                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
 430                 another = find_name(line, NULL, 1, TERM_TAB);
 431                 if (!another || memcmp(another, name, len))
 432                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
 433                 free(another);
 434                 return orig_name;
 435         }
 436         else {
 437                 /* expect "/dev/null" */
 438                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
 439                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
 440                 return NULL;
 441         }
 442 }
 443
 444 static int gitdiff_oldname(const char *line, struct patch *patch)
 445 {
 446         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
 447         return 0;
 448 }
 449
 450 static int gitdiff_newname(const char *line, struct patch *patch)
 451 {
 452         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
 453         return 0;
 454 }
 455
 456 static int gitdiff_oldmode(const char *line, struct patch *patch)
 457 {
 458         patch->old_mode = strtoul(line, NULL, 8);
 459         return 0;
 460 }
 461
 462 static int gitdiff_newmode(const char *line, struct patch *patch)
 463 {
 464         patch->new_mode = strtoul(line, NULL, 8);
 465         return 0;
 466 }
 467
 468 static int gitdiff_delete(const char *line, struct patch *patch)
 469 {
 470         patch->is_delete = 1;
 471         patch->old_name = patch->def_name;
 472         return gitdiff_oldmode(line, patch);
 473 }
 474
 475 static int gitdiff_newfile(const char *line, struct patch *patch)
 476 {
 477         patch->is_new = 1;
 478         patch->new_name = patch->def_name;
 479         return gitdiff_newmode(line, patch);
 480 }
 481
 482 static int gitdiff_copysrc(const char *line, struct patch *patch)
 483 {
 484         patch->is_copy = 1;
 485         patch->old_name = find_name(line, NULL, 0, 0);
 486         return 0;
 487 }
 488
 489 static int gitdiff_copydst(const char *line, struct patch *patch)
 490 {
 491         patch->is_copy = 1;
 492         patch->new_name = find_name(line, NULL, 0, 0);
 493         return 0;
 494 }
 495
 496 static int gitdiff_renamesrc(const char *line, struct patch *patch)
 497 {
 498         patch->is_rename = 1;
 499         patch->old_name = find_name(line, NULL, 0, 0);
 500         return 0;
 501 }
 502
 503 static int gitdiff_renamedst(const char *line, struct patch *patch)
 504 {
 505         patch->is_rename = 1;
 506         patch->new_name = find_name(line, NULL, 0, 0);
 507         return 0;
 508 }
 509
 510 static int gitdiff_similarity(const char *line, struct patch *patch)
 511 {
 512         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 513                 patch->score = 0;
 514         return 0;
 515 }
 516
 517 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
 518 {
 519         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 520                 patch->score = 0;
 521         return 0;
 522 }
 523
 524 static int gitdiff_index(const char *line, struct patch *patch)
 525 {
 526         /* index line is N hexadecimal, "..", N hexadecimal,
 527          * and optional space with octal mode.
 528          */
 529         const char *ptr, *eol;
 530         int len;
 531
 532         ptr = strchr(line, '.');
 533         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
 534                 return 0;
 535         len = ptr - line;
 536         memcpy(patch->old_sha1_prefix, line, len);
 537         patch->old_sha1_prefix[len] = 0;
 538
 539         line = ptr + 2;
 540         ptr = strchr(line, ' ');
 541         eol = strchr(line, '\n');
 542
 543         if (!ptr || eol < ptr)
 544                 ptr = eol;
 545         len = ptr - line;
 546
 547         if (40 < len)
 548                 return 0;
 549         memcpy(patch->new_sha1_prefix, line, len);
 550         patch->new_sha1_prefix[len] = 0;
 551         if (*ptr == ' ')
 552                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
 553         return 0;
 554 }
 555
 556 /*
 557  * This is normal for a diff that doesn't change anything: we'll fall through
 558  * into the next diff. Tell the parser to break out.
 559  */
 560 static int gitdiff_unrecognized(const char *line, struct patch *patch)
 561 {
 562         return -1;
 563 }
 564
 565 static const char *stop_at_slash(const char *line, int llen)
 566 {
 567         int i;
 568
 569         for (i = 0; i < llen; i++) {
 570                 int ch = line[i];
 571                 if (ch == '/')
 572                         return line + i;
 573         }
 574         return NULL;
 575 }
 576
 577 /* This is to extract the same name that appears on "diff --git"
 578  * line.  We do not find and return anything if it is a rename
 579  * patch, and it is OK because we will find the name elsewhere.
 580  * We need to reliably find name only when it is mode-change only,
 581  * creation or deletion of an empty file.  In any of these cases,
 582  * both sides are the same name under a/ and b/ respectively.
 583  */
 584 static char *git_header_name(char *line, int llen)
 585 {
 586         int len;
 587         const char *name;
 588         const char *second = NULL;
 589
 590         line += strlen("diff --git ");
 591         llen -= strlen("diff --git ");
 592
 593         if (*line == '"') {
 594                 const char *cp;
 595                 char *first = unquote_c_style(line, &second);
 596                 if (!first)
 597                         return NULL;
 598
 599                 /* advance to the first slash */
 600                 cp = stop_at_slash(first, strlen(first));
 601                 if (!cp || cp == first) {
 602                         /* we do not accept absolute paths */
 603                 free_first_and_fail:
 604                         free(first);
 605                         return NULL;
 606                 }
 607                 len = strlen(cp+1);
 608                 memmove(first, cp+1, len+1); /* including NUL */
 609
 610                 /* second points at one past closing dq of name.
 611                  * find the second name.
 612                  */
 613                 while ((second < line + llen) && isspace(*second))
 614                         second++;
 615
 616                 if (line + llen <= second)
 617                         goto free_first_and_fail;
 618                 if (*second == '"') {
 619                         char *sp = unquote_c_style(second, NULL);
 620                         if (!sp)
 621                                 goto free_first_and_fail;
 622                         cp = stop_at_slash(sp, strlen(sp));
 623                         if (!cp || cp == sp) {
 624                         free_both_and_fail:
 625                                 free(sp);
 626                                 goto free_first_and_fail;
 627                         }
 628                         /* They must match, otherwise ignore */
 629                         if (strcmp(cp+1, first))
 630                                 goto free_both_and_fail;
 631                         free(sp);
 632                         return first;
 633                 }
 634
 635                 /* unquoted second */
 636                 cp = stop_at_slash(second, line + llen - second);
 637                 if (!cp || cp == second)
 638                         goto free_first_and_fail;
 639                 cp++;
 640                 if (line + llen - cp != len + 1 ||
 641                     memcmp(first, cp, len))
 642                         goto free_first_and_fail;
 643                 return first;
 644         }
 645
 646         /* unquoted first name */
 647         name = stop_at_slash(line, llen);
 648         if (!name || name == line)
 649                 return NULL;
 650
 651         name++;
 652
 653         /* since the first name is unquoted, a dq if exists must be
 654          * the beginning of the second name.
 655          */
 656         for (second = name; second < line + llen; second++) {
 657                 if (*second == '"') {
 658                         const char *cp = second;
 659                         const char *np;
 660                         char *sp = unquote_c_style(second, NULL);
 661
 662                         if (!sp)
 663                                 return NULL;
 664                         np = stop_at_slash(sp, strlen(sp));
 665                         if (!np || np == sp) {
 666                         free_second_and_fail:
 667                                 free(sp);
 668                                 return NULL;
 669                         }
 670                         np++;
 671                         len = strlen(np);
 672                         if (len < cp - name &&
 673                             !strncmp(np, name, len) &&
 674                             isspace(name[len])) {
 675                                 /* Good */
 676                                 memmove(sp, np, len + 1);
 677                                 return sp;
 678                         }
 679                         goto free_second_and_fail;
 680                 }
 681         }
 682
 683         /*
 684          * Accept a name only if it shows up twice, exactly the same
 685          * form.
 686          */
 687         for (len = 0 ; ; len++) {
 688                 switch (name[len]) {
 689                 default:
 690                         continue;
 691                 case '\n':
 692                         return NULL;
 693                 case '\t': case ' ':
 694                         second = name+len;
 695                         for (;;) {
 696                                 char c = *second++;
 697                                 if (c == '\n')
 698                                         return NULL;
 699                                 if (c == '/')
 700                                         break;
 701                         }
 702                         if (second[len] == '\n' && !memcmp(name, second, len)) {
 703                                 char *ret = xmalloc(len + 1);
 704                                 memcpy(ret, name, len);
 705                                 ret[len] = 0;
 706                                 return ret;
 707                         }
 708                 }
 709         }
 710         return NULL;
 711 }
 712
 713 /* Verify that we recognize the lines following a git header */
 714 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
 715 {
 716         unsigned long offset;
 717
 718         /* A git diff has explicit new/delete information, so we don't guess */
 719         patch->is_new = 0;
 720         patch->is_delete = 0;
 721
 722         /*
 723          * Some things may not have the old name in the
 724          * rest of the headers anywhere (pure mode changes,
 725          * or removing or adding empty files), so we get
 726          * the default name from the header.
 727          */
 728         patch->def_name = git_header_name(line, len);
 729
 730         line += len;
 731         size -= len;
 732         linenr++;
 733         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
 734                 static const struct opentry {
 735                         const char *str;
 736                         int (*fn)(const char *, struct patch *);
 737                 } optable[] = {
 738                         { "@@ -", gitdiff_hdrend },
 739                         { "--- ", gitdiff_oldname },
 740                         { "+++ ", gitdiff_newname },
 741                         { "old mode ", gitdiff_oldmode },
 742                         { "new mode ", gitdiff_newmode },
 743                         { "deleted file mode ", gitdiff_delete },
 744                         { "new file mode ", gitdiff_newfile },
 745                         { "copy from ", gitdiff_copysrc },
 746                         { "copy to ", gitdiff_copydst },
 747                         { "rename old ", gitdiff_renamesrc },
 748                         { "rename new ", gitdiff_renamedst },
 749                         { "rename from ", gitdiff_renamesrc },
 750                         { "rename to ", gitdiff_renamedst },
 751                         { "similarity index ", gitdiff_similarity },
 752                         { "dissimilarity index ", gitdiff_dissimilarity },
 753                         { "index ", gitdiff_index },
 754                         { "", gitdiff_unrecognized },
 755                 };
 756                 int i;
 757
 758                 len = linelen(line, size);
 759                 if (!len || line[len-1] != '\n')
 760                         break;
 761                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
 762                         const struct opentry *p = optable + i;
 763                         int oplen = strlen(p->str);
 764                         if (len < oplen || memcmp(p->str, line, oplen))
 765                                 continue;
 766                         if (p->fn(line + oplen, patch) < 0)
 767                                 return offset;
 768                         break;
 769                 }
 770         }
 771
 772         return offset;
 773 }
 774
 775 static int parse_num(const char *line, unsigned long *p)
 776 {
 777         char *ptr;
 778
 779         if (!isdigit(*line))
 780                 return 0;
 781         *p = strtoul(line, &ptr, 10);
 782         return ptr - line;
 783 }
 784
 785 static int parse_range(const char *line, int len, int offset, const char *expect,
 786                         unsigned long *p1, unsigned long *p2)
 787 {
 788         int digits, ex;
 789
 790         if (offset < 0 || offset >= len)
 791                 return -1;
 792         line += offset;
 793         len -= offset;
 794
 795         digits = parse_num(line, p1);
 796         if (!digits)
 797                 return -1;
 798
 799         offset += digits;
 800         line += digits;
 801         len -= digits;
 802
 803         *p2 = 1;
 804         if (*line == ',') {
 805                 digits = parse_num(line+1, p2);
 806                 if (!digits)
 807                         return -1;
 808
 809                 offset += digits+1;
 810                 line += digits+1;
 811                 len -= digits+1;
 812         }
 813
 814         ex = strlen(expect);
 815         if (ex > len)
 816                 return -1;
 817         if (memcmp(line, expect, ex))
 818                 return -1;
 819
 820         return offset + ex;
 821 }
 822
 823 /*
 824  * Parse a unified diff fragment header of the
 825  * form "@@ -a,b +c,d @@"
 826  */
 827 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
 828 {
 829         int offset;
 830
 831         if (!len || line[len-1] != '\n')
 832                 return -1;
 833
 834         /* Figure out the number of lines in a fragment */
 835         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
 836         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 837
 838         return offset;
 839 }
 840
 841 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
 842 {
 843         unsigned long offset, len;
 844
 845         patch->is_toplevel_relative = 0;
 846         patch->is_rename = patch->is_copy = 0;
 847         patch->is_new = patch->is_delete = -1;
 848         patch->old_mode = patch->new_mode = 0;
 849         patch->old_name = patch->new_name = NULL;
 850         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
 851                 unsigned long nextlen;
 852
 853                 len = linelen(line, size);
 854                 if (!len)
 855                         break;
 856
 857                 /* Testing this early allows us to take a few shortcuts.. */
 858                 if (len < 6)
 859                         continue;
 860
 861                 /*
 862                  * Make sure we don't find any unconnected patch fragments.
 863                  * That's a sign that we didn't find a header, and that a
 864                  * patch has become corrupted/broken up.
 865                  */
 866                 if (!memcmp("@@ -", line, 4)) {
 867                         struct fragment dummy;
 868                         if (parse_fragment_header(line, len, &dummy) < 0)
 869                                 continue;
 870                         die("patch fragment without header at line %d: %.*s",
 871                             linenr, (int)len-1, line);
 872                 }
 873
 874                 if (size < len + 6)
 875                         break;
 876
 877                 /*
 878                  * Git patch? It might not have a real patch, just a rename
 879                  * or mode change, so we handle that specially
 880                  */
 881                 if (!memcmp("diff --git ", line, 11)) {
 882                         int git_hdr_len = parse_git_header(line, len, size, patch);
 883                         if (git_hdr_len <= len)
 884                                 continue;
 885                         if (!patch->old_name && !patch->new_name) {
 886                                 if (!patch->def_name)
 887                                         die("git diff header lacks filename information (line %d)", linenr);
 888                                 patch->old_name = patch->new_name = patch->def_name;
 889                         }
 890                         patch->is_toplevel_relative = 1;
 891                         *hdrsize = git_hdr_len;
 892                         return offset;
 893                 }
 894
 895                 /** --- followed by +++ ? */
 896                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
 897                         continue;
 898
 899                 /*
 900                  * We only accept unified patches, so we want it to
 901                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
 902                  * minimum
 903                  */
 904                 nextlen = linelen(line + len, size - len);
 905                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
 906                         continue;
 907
 908                 /* Ok, we'll consider it a patch */
 909                 parse_traditional_patch(line, line+len, patch);
 910                 *hdrsize = len + nextlen;
 911                 linenr += 2;
 912                 return offset;
 913         }
 914         return -1;
 915 }
 916
 917 static void check_whitespace(const char *line, int len)
 918 {
 919         const char *err = "Adds trailing whitespace";
 920         int seen_space = 0;
 921         int i;
 922
 923         /*
 924          * We know len is at least two, since we have a '+' and we
 925          * checked that the last character was a '\n' before calling
 926          * this function.  That is, an addition of an empty line would
 927          * check the '+' here.  Sneaky...
 928          */
 929         if (isspace(line[len-2]))
 930                 goto error;
 931
 932         /*
 933          * Make sure that there is no space followed by a tab in
 934          * indentation.
 935          */
 936         err = "Space in indent is followed by a tab";
 937         for (i = 1; i < len; i++) {
 938                 if (line[i] == '\t') {
 939                         if (seen_space)
 940                                 goto error;
 941                 }
 942                 else if (line[i] == ' ')
 943                         seen_space = 1;
 944                 else
 945                         break;
 946         }
 947         return;
 948
 949  error:
 950         whitespace_error++;
 951         if (squelch_whitespace_errors &&
 952             squelch_whitespace_errors < whitespace_error)
 953                 ;
 954         else
 955                 fprintf(stderr, "%s.\n%s:%d:%.*s\n",
 956                         err, patch_input_file, linenr, len-2, line+1);
 957 }
 958
 959
 960 /*
 961  * Parse a unified diff. Note that this really needs to parse each
 962  * fragment separately, since the only way to know the difference
 963  * between a "---" that is part of a patch, and a "---" that starts
 964  * the next patch is to look at the line counts..
 965  */
 966 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
 967 {
 968         int added, deleted;
 969         int len = linelen(line, size), offset;
 970         unsigned long oldlines, newlines;
 971         unsigned long leading, trailing;
 972
 973         offset = parse_fragment_header(line, len, fragment);
 974         if (offset < 0)
 975                 return -1;
 976         oldlines = fragment->oldlines;
 977         newlines = fragment->newlines;
 978         leading = 0;
 979         trailing = 0;
 980
 981         /* Parse the thing.. */
 982         line += len;
 983         size -= len;
 984         linenr++;
 985         added = deleted = 0;
 986         for (offset = len;
 987              0 < size;
 988              offset += len, size -= len, line += len, linenr++) {
 989                 if (!oldlines && !newlines)
 990                         break;
 991                 len = linelen(line, size);
 992                 if (!len || line[len-1] != '\n')
 993                         return -1;
 994                 switch (*line) {
 995                 default:
 996                         return -1;
 997                 case '\n': /* newer GNU diff, an empty context line */
 998                 case ' ':
 999                         oldlines--;
1000                         newlines--;
1001                         if (!deleted && !added)
1002                                 leading++;
1003                         trailing++;
1004                         break;
1005                 case '-':
1006                         deleted++;
1007                         oldlines--;
1008                         trailing = 0;
1009                         break;
1010                 case '+':
1011                         if (new_whitespace != nowarn_whitespace)
1012                                 check_whitespace(line, len);
1013                         added++;
1014                         newlines--;
1015                         trailing = 0;
1016                         break;
1017
1018                 /* We allow "\ No newline at end of file". Depending
1019                  * on locale settings when the patch was produced we
1020                  * don't know what this line looks like. The only
1021                  * thing we do know is that it begins with "\ ".
1022                  * Checking for 12 is just for sanity check -- any
1023                  * l10n of "\ No newline..." is at least that long.
1024                  */
1025                 case '\\':
1026                         if (len < 12 || memcmp(line, "\\ ", 2))
1027                                 return -1;
1028                         break;
1029                 }
1030         }
1031         if (oldlines || newlines)
1032                 return -1;
1033         fragment->leading = leading;
1034         fragment->trailing = trailing;
1035
1036         /* If a fragment ends with an incomplete line, we failed to include
1037          * it in the above loop because we hit oldlines == newlines == 0
1038          * before seeing it.
1039          */
1040         if (12 < size && !memcmp(line, "\\ ", 2))
1041                 offset += linelen(line, size);
1042
1043         patch->lines_added += added;
1044         patch->lines_deleted += deleted;
1045
1046         if (0 < patch->is_new && oldlines)
1047                 return error("new file depends on old contents");
1048         if (0 < patch->is_delete && newlines)
1049                 return error("deleted file still has contents");
1050         return offset;
1051 }
1052
1053 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1054 {
1055         unsigned long offset = 0;
1056         unsigned long oldlines = 0, newlines = 0, context = 0;
1057         struct fragment **fragp = &patch->fragments;
1058
1059         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1060                 struct fragment *fragment;
1061                 int len;
1062
1063                 fragment = xcalloc(1, sizeof(*fragment));
1064                 len = parse_fragment(line, size, patch, fragment);
1065                 if (len <= 0)
1066                         die("corrupt patch at line %d", linenr);
1067                 fragment->patch = line;
1068                 fragment->size = len;
1069                 oldlines += fragment->oldlines;
1070                 newlines += fragment->newlines;
1071                 context += fragment->leading + fragment->trailing;
1072
1073                 *fragp = fragment;
1074                 fragp = &fragment->next;
1075
1076                 offset += len;
1077                 line += len;
1078                 size -= len;
1079         }
1080
1081         /*
1082          * If something was removed (i.e. we have old-lines) it cannot
1083          * be creation, and if something was added it cannot be
1084          * deletion.  However, the reverse is not true; --unified=0
1085          * patches that only add are not necessarily creation even
1086          * though they do not have any old lines, and ones that only
1087          * delete are not necessarily deletion.
1088          *
1089          * Unfortunately, a real creation/deletion patch do _not_ have
1090          * any context line by definition, so we cannot safely tell it
1091          * apart with --unified=0 insanity.  At least if the patch has
1092          * more than one hunk it is not creation or deletion.
1093          */
1094         if (patch->is_new < 0 &&
1095             (oldlines || (patch->fragments && patch->fragments->next)))
1096                 patch->is_new = 0;
1097         if (patch->is_delete < 0 &&
1098             (newlines || (patch->fragments && patch->fragments->next)))
1099                 patch->is_delete = 0;
1100         if (!unidiff_zero || context) {
1101                 /* If the user says the patch is not generated with
1102                  * --unified=0, or if we have seen context lines,
1103                  * then not having oldlines means the patch is creation,
1104                  * and not having newlines means the patch is deletion.
1105                  */
1106                 if (patch->is_new < 0 && !oldlines) {
1107                         patch->is_new = 1;
1108                         patch->old_name = NULL;
1109                 }
1110                 if (patch->is_delete < 0 && !newlines) {
1111                         patch->is_delete = 1;
1112                         patch->new_name = NULL;
1113                 }
1114         }
1115
1116         if (0 < patch->is_new && oldlines)
1117                 die("new file %s depends on old contents", patch->new_name);
1118         if (0 < patch->is_delete && newlines)
1119                 die("deleted file %s still has contents", patch->old_name);
1120         if (!patch->is_delete && !newlines && context)
1121                 fprintf(stderr, "** warning: file %s becomes empty but "
1122                         "is not deleted\n", patch->new_name);
1123
1124         return offset;
1125 }
1126
1127 static inline int metadata_changes(struct patch *patch)
1128 {
1129         return  patch->is_rename > 0 ||
1130                 patch->is_copy > 0 ||
1131                 patch->is_new > 0 ||
1132                 patch->is_delete ||
1133                 (patch->old_mode && patch->new_mode &&
1134                  patch->old_mode != patch->new_mode);
1135 }
1136
1137 static char *inflate_it(const void *data, unsigned long size,
1138                         unsigned long inflated_size)
1139 {
1140         z_stream stream;
1141         void *out;
1142         int st;
1143
1144         memset(&stream, 0, sizeof(stream));
1145
1146         stream.next_in = (unsigned char *)data;
1147         stream.avail_in = size;
1148         stream.next_out = out = xmalloc(inflated_size);
1149         stream.avail_out = inflated_size;
1150         inflateInit(&stream);
1151         st = inflate(&stream, Z_FINISH);
1152         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1153                 free(out);
1154                 return NULL;
1155         }
1156         return out;
1157 }
1158
1159 static struct fragment *parse_binary_hunk(char **buf_p,
1160                                           unsigned long *sz_p,
1161                                           int *status_p,
1162                                           int *used_p)
1163 {
1164         /* Expect a line that begins with binary patch method ("literal"
1165          * or "delta"), followed by the length of data before deflating.
1166          * a sequence of 'length-byte' followed by base-85 encoded data
1167          * should follow, terminated by a newline.
1168          *
1169          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1170          * and we would limit the patch line to 66 characters,
1171          * so one line can fit up to 13 groups that would decode
1172          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1173          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1174          */
1175         int llen, used;
1176         unsigned long size = *sz_p;
1177         char *buffer = *buf_p;
1178         int patch_method;
1179         unsigned long origlen;
1180         char *data = NULL;
1181         int hunk_size = 0;
1182         struct fragment *frag;
1183
1184         llen = linelen(buffer, size);
1185         used = llen;
1186
1187         *status_p = 0;
1188
1189         if (!prefixcmp(buffer, "delta ")) {
1190                 patch_method = BINARY_DELTA_DEFLATED;
1191                 origlen = strtoul(buffer + 6, NULL, 10);
1192         }
1193         else if (!prefixcmp(buffer, "literal ")) {
1194                 patch_method = BINARY_LITERAL_DEFLATED;
1195                 origlen = strtoul(buffer + 8, NULL, 10);
1196         }
1197         else
1198                 return NULL;
1199
1200         linenr++;
1201         buffer += llen;
1202         while (1) {
1203                 int byte_length, max_byte_length, newsize;
1204                 llen = linelen(buffer, size);
1205                 used += llen;
1206                 linenr++;
1207                 if (llen == 1) {
1208                         /* consume the blank line */
1209                         buffer++;
1210                         size--;
1211                         break;
1212                 }
1213                 /* Minimum line is "A00000\n" which is 7-byte long,
1214                  * and the line length must be multiple of 5 plus 2.
1215                  */
1216                 if ((llen < 7) || (llen-2) % 5)
1217                         goto corrupt;
1218                 max_byte_length = (llen - 2) / 5 * 4;
1219                 byte_length = *buffer;
1220                 if ('A' <= byte_length && byte_length <= 'Z')
1221                         byte_length = byte_length - 'A' + 1;
1222                 else if ('a' <= byte_length && byte_length <= 'z')
1223                         byte_length = byte_length - 'a' + 27;
1224                 else
1225                         goto corrupt;
1226                 /* if the input length was not multiple of 4, we would
1227                  * have filler at the end but the filler should never
1228                  * exceed 3 bytes
1229                  */
1230                 if (max_byte_length < byte_length ||
1231                     byte_length <= max_byte_length - 4)
1232                         goto corrupt;
1233                 newsize = hunk_size + byte_length;
1234                 data = xrealloc(data, newsize);
1235                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1236                         goto corrupt;
1237                 hunk_size = newsize;
1238                 buffer += llen;
1239                 size -= llen;
1240         }
1241
1242         frag = xcalloc(1, sizeof(*frag));
1243         frag->patch = inflate_it(data, hunk_size, origlen);
1244         if (!frag->patch)
1245                 goto corrupt;
1246         free(data);
1247         frag->size = origlen;
1248         *buf_p = buffer;
1249         *sz_p = size;
1250         *used_p = used;
1251         frag->binary_patch_method = patch_method;
1252         return frag;
1253
1254  corrupt:
1255         free(data);
1256         *status_p = -1;
1257         error("corrupt binary patch at line %d: %.*s",
1258               linenr-1, llen-1, buffer);
1259         return NULL;
1260 }
1261
1262 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1263 {
1264         /* We have read "GIT binary patch\n"; what follows is a line
1265          * that says the patch method (currently, either "literal" or
1266          * "delta") and the length of data before deflating; a
1267          * sequence of 'length-byte' followed by base-85 encoded data
1268          * follows.
1269          *
1270          * When a binary patch is reversible, there is another binary
1271          * hunk in the same format, starting with patch method (either
1272          * "literal" or "delta") with the length of data, and a sequence
1273          * of length-byte + base-85 encoded data, terminated with another
1274          * empty line.  This data, when applied to the postimage, produces
1275          * the preimage.
1276          */
1277         struct fragment *forward;
1278         struct fragment *reverse;
1279         int status;
1280         int used, used_1;
1281
1282         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1283         if (!forward && !status)
1284                 /* there has to be one hunk (forward hunk) */
1285                 return error("unrecognized binary patch at line %d", linenr-1);
1286         if (status)
1287                 /* otherwise we already gave an error message */
1288                 return status;
1289
1290         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1291         if (reverse)
1292                 used += used_1;
1293         else if (status) {
1294                 /* not having reverse hunk is not an error, but having
1295                  * a corrupt reverse hunk is.
1296                  */
1297                 free((void*) forward->patch);
1298                 free(forward);
1299                 return status;
1300         }
1301         forward->next = reverse;
1302         patch->fragments = forward;
1303         patch->is_binary = 1;
1304         return used;
1305 }
1306
1307 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1308 {
1309         int hdrsize, patchsize;
1310         int offset = find_header(buffer, size, &hdrsize, patch);
1311
1312         if (offset < 0)
1313                 return offset;
1314
1315         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
1316
1317         if (!patchsize) {
1318                 static const char *binhdr[] = {
1319                         "Binary files ",
1320                         "Files ",
1321                         NULL,
1322                 };
1323                 static const char git_binary[] = "GIT binary patch\n";
1324                 int i;
1325                 int hd = hdrsize + offset;
1326                 unsigned long llen = linelen(buffer + hd, size - hd);
1327
1328                 if (llen == sizeof(git_binary) - 1 &&
1329                     !memcmp(git_binary, buffer + hd, llen)) {
1330                         int used;
1331                         linenr++;
1332                         used = parse_binary(buffer + hd + llen,
1333                                             size - hd - llen, patch);
1334                         if (used)
1335                                 patchsize = used + llen;
1336                         else
1337                                 patchsize = 0;
1338                 }
1339                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1340                         for (i = 0; binhdr[i]; i++) {
1341                                 int len = strlen(binhdr[i]);
1342                                 if (len < size - hd &&
1343                                     !memcmp(binhdr[i], buffer + hd, len)) {
1344                                         linenr++;
1345                                         patch->is_binary = 1;
1346                                         patchsize = llen;
1347                                         break;
1348                                 }
1349                         }
1350                 }
1351
1352                 /* Empty patch cannot be applied if it is a text patch
1353                  * without metadata change.  A binary patch appears
1354                  * empty to us here.
1355                  */
1356                 if ((apply || check) &&
1357                     (!patch->is_binary && !metadata_changes(patch)))
1358                         die("patch with only garbage at line %d", linenr);
1359         }
1360
1361         return offset + hdrsize + patchsize;
1362 }
1363
1364 #define swap(a,b) myswap((a),(b),sizeof(a))
1365
1366 #define myswap(a, b, size) do {         \
1367         unsigned char mytmp[size];      \
1368         memcpy(mytmp, &a, size);                \
1369         memcpy(&a, &b, size);           \
1370         memcpy(&b, mytmp, size);                \
1371 } while (0)
1372
1373 static void reverse_patches(struct patch *p)
1374 {
1375         for (; p; p = p->next) {
1376                 struct fragment *frag = p->fragments;
1377
1378                 swap(p->new_name, p->old_name);
1379                 swap(p->new_mode, p->old_mode);
1380                 swap(p->is_new, p->is_delete);
1381                 swap(p->lines_added, p->lines_deleted);
1382                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1383
1384                 for (; frag; frag = frag->next) {
1385                         swap(frag->newpos, frag->oldpos);
1386                         swap(frag->newlines, frag->oldlines);
1387                 }
1388         }
1389 }
1390
1391 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1392 static const char minuses[]= "----------------------------------------------------------------------";
1393
1394 static void show_stats(struct patch *patch)
1395 {
1396         const char *prefix = "";
1397         char *name = patch->new_name;
1398         char *qname = NULL;
1399         int len, max, add, del, total;
1400
1401         if (!name)
1402                 name = patch->old_name;
1403
1404         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
1405                 qname = xmalloc(len + 1);
1406                 quote_c_style(name, qname, NULL, 0);
1407                 name = qname;
1408         }
1409
1410         /*
1411          * "scale" the filename
1412          */
1413         len = strlen(name);
1414         max = max_len;
1415         if (max > 50)
1416                 max = 50;
1417         if (len > max) {
1418                 char *slash;
1419                 prefix = "...";
1420                 max -= 3;
1421                 name += len - max;
1422                 slash = strchr(name, '/');
1423                 if (slash)
1424                         name = slash;
1425         }
1426         len = max;
1427
1428         /*
1429          * scale the add/delete
1430          */
1431         max = max_change;
1432         if (max + len > 70)
1433                 max = 70 - len;
1434
1435         add = patch->lines_added;
1436         del = patch->lines_deleted;
1437         total = add + del;
1438
1439         if (max_change > 0) {
1440                 total = (total * max + max_change / 2) / max_change;
1441                 add = (add * max + max_change / 2) / max_change;
1442                 del = total - add;
1443         }
1444         if (patch->is_binary)
1445                 printf(" %s%-*s |  Bin\n", prefix, len, name);
1446         else
1447                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1448                        len, name, patch->lines_added + patch->lines_deleted,
1449                        add, pluses, del, minuses);
1450         free(qname);
1451 }
1452
1453 static int read_old_data(struct stat *st, const char *path, char **buf_p, unsigned long *alloc_p, unsigned long *size_p)
1454 {
1455         int fd;
1456         unsigned long got;
1457         unsigned long nsize;
1458         char *nbuf;
1459         unsigned long size = *size_p;
1460         char *buf = *buf_p;
1461
1462         switch (st->st_mode & S_IFMT) {
1463         case S_IFLNK:
1464                 return readlink(path, buf, size) != size;
1465         case S_IFREG:
1466                 fd = open(path, O_RDONLY);
1467                 if (fd < 0)
1468                         return error("unable to open %s", path);
1469                 got = 0;
1470                 for (;;) {
1471                         int ret = xread(fd, buf + got, size - got);
1472                         if (ret <= 0)
1473                                 break;
1474                         got += ret;
1475                 }
1476                 close(fd);
1477                 nsize = got;
1478                 nbuf = buf;
1479                 if (convert_to_git(path, &nbuf, &nsize)) {
1480                         free(buf);
1481                         *buf_p = nbuf;
1482                         *alloc_p = nsize;
1483                         *size_p = nsize;
1484                 }
1485                 return got != size;
1486         default:
1487                 return -1;
1488         }
1489 }
1490
1491 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
1492 {
1493         int i;
1494         unsigned long start, backwards, forwards;
1495
1496         if (fragsize > size)
1497                 return -1;
1498
1499         start = 0;
1500         if (line > 1) {
1501                 unsigned long offset = 0;
1502                 i = line-1;
1503                 while (offset + fragsize <= size) {
1504                         if (buf[offset++] == '\n') {
1505                                 start = offset;
1506                                 if (!--i)
1507                                         break;
1508                         }
1509                 }
1510         }
1511
1512         /* Exact line number? */
1513         if (!memcmp(buf + start, fragment, fragsize))
1514                 return start;
1515
1516         /*
1517          * There's probably some smart way to do this, but I'll leave
1518          * that to the smart and beautiful people. I'm simple and stupid.
1519          */
1520         backwards = start;
1521         forwards = start;
1522         for (i = 0; ; i++) {
1523                 unsigned long try;
1524                 int n;
1525
1526                 /* "backward" */
1527                 if (i & 1) {
1528                         if (!backwards) {
1529                                 if (forwards + fragsize > size)
1530                                         break;
1531                                 continue;
1532                         }
1533                         do {
1534                                 --backwards;
1535                         } while (backwards && buf[backwards-1] != '\n');
1536                         try = backwards;
1537                 } else {
1538                         while (forwards + fragsize <= size) {
1539                                 if (buf[forwards++] == '\n')
1540                                         break;
1541                         }
1542                         try = forwards;
1543                 }
1544
1545                 if (try + fragsize > size)
1546                         continue;
1547                 if (memcmp(buf + try, fragment, fragsize))
1548                         continue;
1549                 n = (i >> 1)+1;
1550                 if (i & 1)
1551                         n = -n;
1552                 *lines = n;
1553                 return try;
1554         }
1555
1556         /*
1557          * We should start searching forward and backward.
1558          */
1559         return -1;
1560 }
1561
1562 static void remove_first_line(const char **rbuf, int *rsize)
1563 {
1564         const char *buf = *rbuf;
1565         int size = *rsize;
1566         unsigned long offset;
1567         offset = 0;
1568         while (offset <= size) {
1569                 if (buf[offset++] == '\n')
1570                         break;
1571         }
1572         *rsize = size - offset;
1573         *rbuf = buf + offset;
1574 }
1575
1576 static void remove_last_line(const char **rbuf, int *rsize)
1577 {
1578         const char *buf = *rbuf;
1579         int size = *rsize;
1580         unsigned long offset;
1581         offset = size - 1;
1582         while (offset > 0) {
1583                 if (buf[--offset] == '\n')
1584                         break;
1585         }
1586         *rsize = offset + 1;
1587 }
1588
1589 struct buffer_desc {
1590         char *buffer;
1591         unsigned long size;
1592         unsigned long alloc;
1593 };
1594
1595 static int apply_line(char *output, const char *patch, int plen)
1596 {
1597         /* plen is number of bytes to be copied from patch,
1598          * starting at patch+1 (patch[0] is '+').  Typically
1599          * patch[plen] is '\n', unless this is the incomplete
1600          * last line.
1601          */
1602         int i;
1603         int add_nl_to_tail = 0;
1604         int fixed = 0;
1605         int last_tab_in_indent = -1;
1606         int last_space_in_indent = -1;
1607         int need_fix_leading_space = 0;
1608         char *buf;
1609
1610         if ((new_whitespace != strip_whitespace) || !whitespace_error) {
1611                 memcpy(output, patch + 1, plen);
1612                 return plen;
1613         }
1614
1615         if (1 < plen && isspace(patch[plen-1])) {
1616                 if (patch[plen] == '\n')
1617                         add_nl_to_tail = 1;
1618                 plen--;
1619                 while (0 < plen && isspace(patch[plen]))
1620                         plen--;
1621                 fixed = 1;
1622         }
1623
1624         for (i = 1; i < plen; i++) {
1625                 char ch = patch[i];
1626                 if (ch == '\t') {
1627                         last_tab_in_indent = i;
1628                         if (0 <= last_space_in_indent)
1629                                 need_fix_leading_space = 1;
1630                 }
1631                 else if (ch == ' ')
1632                         last_space_in_indent = i;
1633                 else
1634                         break;
1635         }
1636
1637         buf = output;
1638         if (need_fix_leading_space) {
1639                 /* between patch[1..last_tab_in_indent] strip the
1640                  * funny spaces, updating them to tab as needed.
1641                  */
1642                 for (i = 1; i < last_tab_in_indent; i++, plen--) {
1643                         char ch = patch[i];
1644                         if (ch != ' ')
1645                                 *output++ = ch;
1646                         else if ((i % 8) == 0)
1647                                 *output++ = '\t';
1648                 }
1649                 fixed = 1;
1650                 i = last_tab_in_indent;
1651         }
1652         else
1653                 i = 1;
1654
1655         memcpy(output, patch + i, plen);
1656         if (add_nl_to_tail)
1657                 output[plen++] = '\n';
1658         if (fixed)
1659                 applied_after_stripping++;
1660         return output + plen - buf;
1661 }
1662
1663 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag, int inaccurate_eof)
1664 {
1665         int match_beginning, match_end;
1666         char *buf = desc->buffer;
1667         const char *patch = frag->patch;
1668         int offset, size = frag->size;
1669         char *old = xmalloc(size);
1670         char *new = xmalloc(size);
1671         const char *oldlines, *newlines;
1672         int oldsize = 0, newsize = 0;
1673         unsigned long leading, trailing;
1674         int pos, lines;
1675
1676         while (size > 0) {
1677                 char first;
1678                 int len = linelen(patch, size);
1679                 int plen;
1680
1681                 if (!len)
1682                         break;
1683
1684                 /*
1685                  * "plen" is how much of the line we should use for
1686                  * the actual patch data. Normally we just remove the
1687                  * first character on the line, but if the line is
1688                  * followed by "\ No newline", then we also remove the
1689                  * last one (which is the newline, of course).
1690                  */
1691                 plen = len-1;
1692                 if (len < size && patch[len] == '\\')
1693                         plen--;
1694                 first = *patch;
1695                 if (apply_in_reverse) {
1696                         if (first == '-')
1697                                 first = '+';
1698                         else if (first == '+')
1699                                 first = '-';
1700                 }
1701                 switch (first) {
1702                 case '\n':
1703                         /* Newer GNU diff, empty context line */
1704                         if (plen < 0)
1705                                 /* ... followed by '\No newline'; nothing */
1706                                 break;
1707                         old[oldsize++] = '\n';
1708                         new[newsize++] = '\n';
1709                         break;
1710                 case ' ':
1711                 case '-':
1712                         memcpy(old + oldsize, patch + 1, plen);
1713                         oldsize += plen;
1714                         if (first == '-')
1715                                 break;
1716                 /* Fall-through for ' ' */
1717                 case '+':
1718                         if (first != '+' || !no_add)
1719                                 newsize += apply_line(new + newsize, patch,
1720                                                       plen);
1721                         break;
1722                 case '@': case '\\':
1723                         /* Ignore it, we already handled it */
1724                         break;
1725                 default:
1726                         return -1;
1727                 }
1728                 patch += len;
1729                 size -= len;
1730         }
1731
1732         if (inaccurate_eof && oldsize > 0 && old[oldsize - 1] == '\n' &&
1733                         newsize > 0 && new[newsize - 1] == '\n') {
1734                 oldsize--;
1735                 newsize--;
1736         }
1737
1738         oldlines = old;
1739         newlines = new;
1740         leading = frag->leading;
1741         trailing = frag->trailing;
1742
1743         /*
1744          * If we don't have any leading/trailing data in the patch,
1745          * we want it to match at the beginning/end of the file.
1746          *
1747          * But that would break if the patch is generated with
1748          * --unified=0; sane people wouldn't do that to cause us
1749          * trouble, but we try to please not so sane ones as well.
1750          */
1751         if (unidiff_zero) {
1752                 match_beginning = (!leading && !frag->oldpos);
1753                 match_end = 0;
1754         }
1755         else {
1756                 match_beginning = !leading && (frag->oldpos == 1);
1757                 match_end = !trailing;
1758         }
1759
1760         lines = 0;
1761         pos = frag->newpos;
1762         for (;;) {
1763                 offset = find_offset(buf, desc->size,
1764                                      oldlines, oldsize, pos, &lines);
1765                 if (match_end && offset + oldsize != desc->size)
1766                         offset = -1;
1767                 if (match_beginning && offset)
1768                         offset = -1;
1769                 if (offset >= 0) {
1770                         int diff = newsize - oldsize;
1771                         unsigned long size = desc->size + diff;
1772                         unsigned long alloc = desc->alloc;
1773
1774                         /* Warn if it was necessary to reduce the number
1775                          * of context lines.
1776                          */
1777                         if ((leading != frag->leading) ||
1778                             (trailing != frag->trailing))
1779                                 fprintf(stderr, "Context reduced to (%ld/%ld)"
1780                                         " to apply fragment at %d\n",
1781                                         leading, trailing, pos + lines);
1782
1783                         if (size > alloc) {
1784                                 alloc = size + 8192;
1785                                 desc->alloc = alloc;
1786                                 buf = xrealloc(buf, alloc);
1787                                 desc->buffer = buf;
1788                         }
1789                         desc->size = size;
1790                         memmove(buf + offset + newsize,
1791                                 buf + offset + oldsize,
1792                                 size - offset - newsize);
1793                         memcpy(buf + offset, newlines, newsize);
1794                         offset = 0;
1795
1796                         break;
1797                 }
1798
1799                 /* Am I at my context limits? */
1800                 if ((leading <= p_context) && (trailing <= p_context))
1801                         break;
1802                 if (match_beginning || match_end) {
1803                         match_beginning = match_end = 0;
1804                         continue;
1805                 }
1806                 /* Reduce the number of context lines
1807                  * Reduce both leading and trailing if they are equal
1808                  * otherwise just reduce the larger context.
1809                  */
1810                 if (leading >= trailing) {
1811                         remove_first_line(&oldlines, &oldsize);
1812                         remove_first_line(&newlines, &newsize);
1813                         pos--;
1814                         leading--;
1815                 }
1816                 if (trailing > leading) {
1817                         remove_last_line(&oldlines, &oldsize);
1818                         remove_last_line(&newlines, &newsize);
1819                         trailing--;
1820                 }
1821         }
1822
1823         free(old);
1824         free(new);
1825         return offset;
1826 }
1827
1828 static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch)
1829 {
1830         unsigned long dst_size;
1831         struct fragment *fragment = patch->fragments;
1832         void *data;
1833         void *result;
1834
1835         /* Binary patch is irreversible without the optional second hunk */
1836         if (apply_in_reverse) {
1837                 if (!fragment->next)
1838                         return error("cannot reverse-apply a binary patch "
1839                                      "without the reverse hunk to '%s'",
1840                                      patch->new_name
1841                                      ? patch->new_name : patch->old_name);
1842                 fragment = fragment->next;
1843         }
1844         data = (void*) fragment->patch;
1845         switch (fragment->binary_patch_method) {
1846         case BINARY_DELTA_DEFLATED:
1847                 result = patch_delta(desc->buffer, desc->size,
1848                                      data,
1849                                      fragment->size,
1850                                      &dst_size);
1851                 free(desc->buffer);
1852                 desc->buffer = result;
1853                 break;
1854         case BINARY_LITERAL_DEFLATED:
1855                 free(desc->buffer);
1856                 desc->buffer = data;
1857                 dst_size = fragment->size;
1858                 break;
1859         }
1860         if (!desc->buffer)
1861                 return -1;
1862         desc->size = desc->alloc = dst_size;
1863         return 0;
1864 }
1865
1866 static int apply_binary(struct buffer_desc *desc, struct patch *patch)
1867 {
1868         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1869         unsigned char sha1[20];
1870
1871         /* For safety, we require patch index line to contain
1872          * full 40-byte textual SHA1 for old and new, at least for now.
1873          */
1874         if (strlen(patch->old_sha1_prefix) != 40 ||
1875             strlen(patch->new_sha1_prefix) != 40 ||
1876             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1877             get_sha1_hex(patch->new_sha1_prefix, sha1))
1878                 return error("cannot apply binary patch to '%s' "
1879                              "without full index line", name);
1880
1881         if (patch->old_name) {
1882                 /* See if the old one matches what the patch
1883                  * applies to.
1884                  */
1885                 hash_sha1_file(desc->buffer, desc->size, blob_type, sha1);
1886                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1887                         return error("the patch applies to '%s' (%s), "
1888                                      "which does not match the "
1889                                      "current contents.",
1890                                      name, sha1_to_hex(sha1));
1891         }
1892         else {
1893                 /* Otherwise, the old one must be empty. */
1894                 if (desc->size)
1895                         return error("the patch applies to an empty "
1896                                      "'%s' but it is not empty", name);
1897         }
1898
1899         get_sha1_hex(patch->new_sha1_prefix, sha1);
1900         if (is_null_sha1(sha1)) {
1901                 free(desc->buffer);
1902                 desc->alloc = desc->size = 0;
1903                 desc->buffer = NULL;
1904                 return 0; /* deletion patch */
1905         }
1906
1907         if (has_sha1_file(sha1)) {
1908                 /* We already have the postimage */
1909                 char type[10];
1910                 unsigned long size;
1911
1912                 free(desc->buffer);
1913                 desc->buffer = read_sha1_file(sha1, type, &size);
1914                 if (!desc->buffer)
1915                         return error("the necessary postimage %s for "
1916                                      "'%s' cannot be read",
1917                                      patch->new_sha1_prefix, name);
1918                 desc->alloc = desc->size = size;
1919         }
1920         else {
1921                 /* We have verified desc matches the preimage;
1922                  * apply the patch data to it, which is stored
1923                  * in the patch->fragments->{patch,size}.
1924                  */
1925                 if (apply_binary_fragment(desc, patch))
1926                         return error("binary patch does not apply to '%s'",
1927                                      name);
1928
1929                 /* verify that the result matches */
1930                 hash_sha1_file(desc->buffer, desc->size, blob_type, sha1);
1931                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
1932                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)", name, patch->new_sha1_prefix, sha1_to_hex(sha1));
1933         }
1934
1935         return 0;
1936 }
1937
1938 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1939 {
1940         struct fragment *frag = patch->fragments;
1941         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1942
1943         if (patch->is_binary)
1944                 return apply_binary(desc, patch);
1945
1946         while (frag) {
1947                 if (apply_one_fragment(desc, frag, patch->inaccurate_eof)) {
1948                         error("patch failed: %s:%ld", name, frag->oldpos);
1949                         if (!apply_with_reject)
1950                                 return -1;
1951                         frag->rejected = 1;
1952                 }
1953                 frag = frag->next;
1954         }
1955         return 0;
1956 }
1957
1958 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
1959 {
1960         char *buf;
1961         unsigned long size, alloc;
1962         struct buffer_desc desc;
1963
1964         size = 0;
1965         alloc = 0;
1966         buf = NULL;
1967         if (cached) {
1968                 if (ce) {
1969                         char type[20];
1970                         buf = read_sha1_file(ce->sha1, type, &size);
1971                         if (!buf)
1972                                 return error("read of %s failed",
1973                                              patch->old_name);
1974                         alloc = size;
1975                 }
1976         }
1977         else if (patch->old_name) {
1978                 size = st->st_size;
1979                 alloc = size + 8192;
1980                 buf = xmalloc(alloc);
1981                 if (read_old_data(st, patch->old_name, &buf, &alloc, &size))
1982                         return error("read of %s failed", patch->old_name);
1983         }
1984
1985         desc.size = size;
1986         desc.alloc = alloc;
1987         desc.buffer = buf;
1988
1989         if (apply_fragments(&desc, patch) < 0)
1990                 return -1; /* note with --reject this succeeds. */
1991
1992         /* NUL terminate the result */
1993         if (desc.alloc <= desc.size)
1994                 desc.buffer = xrealloc(desc.buffer, desc.size + 1);
1995         desc.buffer[desc.size] = 0;
1996
1997         patch->result = desc.buffer;
1998         patch->resultsize = desc.size;
1999
2000         if (0 < patch->is_delete && patch->resultsize)
2001                 return error("removal patch leaves file contents");
2002
2003         return 0;
2004 }
2005
2006 static int check_patch(struct patch *patch, struct patch *prev_patch)
2007 {
2008         struct stat st;
2009         const char *old_name = patch->old_name;
2010         const char *new_name = patch->new_name;
2011         const char *name = old_name ? old_name : new_name;
2012         struct cache_entry *ce = NULL;
2013         int ok_if_exists;
2014
2015         patch->rejected = 1; /* we will drop this after we succeed */
2016         if (old_name) {
2017                 int changed = 0;
2018                 int stat_ret = 0;
2019                 unsigned st_mode = 0;
2020
2021                 if (!cached)
2022                         stat_ret = lstat(old_name, &st);
2023                 if (check_index) {
2024                         int pos = cache_name_pos(old_name, strlen(old_name));
2025                         if (pos < 0)
2026                                 return error("%s: does not exist in index",
2027                                              old_name);
2028                         ce = active_cache[pos];
2029                         if (stat_ret < 0) {
2030                                 struct checkout costate;
2031                                 if (errno != ENOENT)
2032                                         return error("%s: %s", old_name,
2033                                                      strerror(errno));
2034                                 /* checkout */
2035                                 costate.base_dir = "";
2036                                 costate.base_dir_len = 0;
2037                                 costate.force = 0;
2038                                 costate.quiet = 0;
2039                                 costate.not_new = 0;
2040                                 costate.refresh_cache = 1;
2041                                 if (checkout_entry(ce,
2042                                                    &costate,
2043                                                    NULL) ||
2044                                     lstat(old_name, &st))
2045                                         return -1;
2046                         }
2047                         if (!cached)
2048                                 changed = ce_match_stat(ce, &st, 1);
2049                         if (changed)
2050                                 return error("%s: does not match index",
2051                                              old_name);
2052                         if (cached)
2053                                 st_mode = ntohl(ce->ce_mode);
2054                 }
2055                 else if (stat_ret < 0)
2056                         return error("%s: %s", old_name, strerror(errno));
2057
2058                 if (!cached)
2059                         st_mode = ntohl(ce_mode_from_stat(ce, st.st_mode));
2060
2061                 if (patch->is_new < 0)
2062                         patch->is_new = 0;
2063                 if (!patch->old_mode)
2064                         patch->old_mode = st_mode;
2065                 if ((st_mode ^ patch->old_mode) & S_IFMT)
2066                         return error("%s: wrong type", old_name);
2067                 if (st_mode != patch->old_mode)
2068                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
2069                                 old_name, st_mode, patch->old_mode);
2070         }
2071
2072         if (new_name && prev_patch && 0 < prev_patch->is_delete &&
2073             !strcmp(prev_patch->old_name, new_name))
2074                 /* A type-change diff is always split into a patch to
2075                  * delete old, immediately followed by a patch to
2076                  * create new (see diff.c::run_diff()); in such a case
2077                  * it is Ok that the entry to be deleted by the
2078                  * previous patch is still in the working tree and in
2079                  * the index.
2080                  */
2081                 ok_if_exists = 1;
2082         else
2083                 ok_if_exists = 0;
2084
2085         if (new_name &&
2086             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2087                 if (check_index &&
2088                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2089                     !ok_if_exists)
2090                         return error("%s: already exists in index", new_name);
2091                 if (!cached) {
2092                         struct stat nst;
2093                         if (!lstat(new_name, &nst)) {
2094                                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2095                                         ; /* ok */
2096                                 else
2097                                         return error("%s: already exists in working directory", new_name);
2098                         }
2099                         else if ((errno != ENOENT) && (errno != ENOTDIR))
2100                                 return error("%s: %s", new_name, strerror(errno));
2101                 }
2102                 if (!patch->new_mode) {
2103                         if (0 < patch->is_new)
2104                                 patch->new_mode = S_IFREG | 0644;
2105                         else
2106                                 patch->new_mode = patch->old_mode;
2107                 }
2108         }
2109
2110         if (new_name && old_name) {
2111                 int same = !strcmp(old_name, new_name);
2112                 if (!patch->new_mode)
2113                         patch->new_mode = patch->old_mode;
2114                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2115                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2116                                 patch->new_mode, new_name, patch->old_mode,
2117                                 same ? "" : " of ", same ? "" : old_name);
2118         }
2119
2120         if (apply_data(patch, &st, ce) < 0)
2121                 return error("%s: patch does not apply", name);
2122         patch->rejected = 0;
2123         return 0;
2124 }
2125
2126 static int check_patch_list(struct patch *patch)
2127 {
2128         struct patch *prev_patch = NULL;
2129         int err = 0;
2130
2131         for (prev_patch = NULL; patch ; patch = patch->next) {
2132                 if (apply_verbosely)
2133                         say_patch_name(stderr,
2134                                        "Checking patch ", patch, "...\n");
2135                 err |= check_patch(patch, prev_patch);
2136                 prev_patch = patch;
2137         }
2138         return err;
2139 }
2140
2141 static void show_index_list(struct patch *list)
2142 {
2143         struct patch *patch;
2144
2145         /* Once we start supporting the reverse patch, it may be
2146          * worth showing the new sha1 prefix, but until then...
2147          */
2148         for (patch = list; patch; patch = patch->next) {
2149                 const unsigned char *sha1_ptr;
2150                 unsigned char sha1[20];
2151                 const char *name;
2152
2153                 name = patch->old_name ? patch->old_name : patch->new_name;
2154                 if (0 < patch->is_new)
2155                         sha1_ptr = null_sha1;
2156                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2157                         die("sha1 information is lacking or useless (%s).",
2158                             name);
2159                 else
2160                         sha1_ptr = sha1;
2161
2162                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
2163                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
2164                         quote_c_style(name, NULL, stdout, 0);
2165                 else
2166                         fputs(name, stdout);
2167                 putchar(line_termination);
2168         }
2169 }
2170
2171 static void stat_patch_list(struct patch *patch)
2172 {
2173         int files, adds, dels;
2174
2175         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2176                 files++;
2177                 adds += patch->lines_added;
2178                 dels += patch->lines_deleted;
2179                 show_stats(patch);
2180         }
2181
2182         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2183 }
2184
2185 static void numstat_patch_list(struct patch *patch)
2186 {
2187         for ( ; patch; patch = patch->next) {
2188                 const char *name;
2189                 name = patch->new_name ? patch->new_name : patch->old_name;
2190                 if (patch->is_binary)
2191                         printf("-\t-\t");
2192                 else
2193                         printf("%d\t%d\t",
2194                                patch->lines_added, patch->lines_deleted);
2195                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
2196                         quote_c_style(name, NULL, stdout, 0);
2197                 else
2198                         fputs(name, stdout);
2199                 putchar(line_termination);
2200         }
2201 }
2202
2203 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2204 {
2205         if (mode)
2206                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2207         else
2208                 printf(" %s %s\n", newdelete, name);
2209 }
2210
2211 static void show_mode_change(struct patch *p, int show_name)
2212 {
2213         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2214                 if (show_name)
2215                         printf(" mode change %06o => %06o %s\n",
2216                                p->old_mode, p->new_mode, p->new_name);
2217                 else
2218                         printf(" mode change %06o => %06o\n",
2219                                p->old_mode, p->new_mode);
2220         }
2221 }
2222
2223 static void show_rename_copy(struct patch *p)
2224 {
2225         const char *renamecopy = p->is_rename ? "rename" : "copy";
2226         const char *old, *new;
2227
2228         /* Find common prefix */
2229         old = p->old_name;
2230         new = p->new_name;
2231         while (1) {
2232                 const char *slash_old, *slash_new;
2233                 slash_old = strchr(old, '/');
2234                 slash_new = strchr(new, '/');
2235                 if (!slash_old ||
2236                     !slash_new ||
2237                     slash_old - old != slash_new - new ||
2238                     memcmp(old, new, slash_new - new))
2239                         break;
2240                 old = slash_old + 1;
2241                 new = slash_new + 1;
2242         }
2243         /* p->old_name thru old is the common prefix, and old and new
2244          * through the end of names are renames
2245          */
2246         if (old != p->old_name)
2247                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2248                        (int)(old - p->old_name), p->old_name,
2249                        old, new, p->score);
2250         else
2251                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2252                        p->old_name, p->new_name, p->score);
2253         show_mode_change(p, 0);
2254 }
2255
2256 static void summary_patch_list(struct patch *patch)
2257 {
2258         struct patch *p;
2259
2260         for (p = patch; p; p = p->next) {
2261                 if (p->is_new)
2262                         show_file_mode_name("create", p->new_mode, p->new_name);
2263                 else if (p->is_delete)
2264                         show_file_mode_name("delete", p->old_mode, p->old_name);
2265                 else {
2266                         if (p->is_rename || p->is_copy)
2267                                 show_rename_copy(p);
2268                         else {
2269                                 if (p->score) {
2270                                         printf(" rewrite %s (%d%%)\n",
2271                                                p->new_name, p->score);
2272                                         show_mode_change(p, 0);
2273                                 }
2274                                 else
2275                                         show_mode_change(p, 1);
2276                         }
2277                 }
2278         }
2279 }
2280
2281 static void patch_stats(struct patch *patch)
2282 {
2283         int lines = patch->lines_added + patch->lines_deleted;
2284
2285         if (lines > max_change)
2286                 max_change = lines;
2287         if (patch->old_name) {
2288                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2289                 if (!len)
2290                         len = strlen(patch->old_name);
2291                 if (len > max_len)
2292                         max_len = len;
2293         }
2294         if (patch->new_name) {
2295                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2296                 if (!len)
2297                         len = strlen(patch->new_name);
2298                 if (len > max_len)
2299                         max_len = len;
2300         }
2301 }
2302
2303 static void remove_file(struct patch *patch, int rmdir_empty)
2304 {
2305         if (write_index) {
2306                 if (remove_file_from_cache(patch->old_name) < 0)
2307                         die("unable to remove %s from index", patch->old_name);
2308                 cache_tree_invalidate_path(active_cache_tree, patch->old_name);
2309         }
2310         if (!cached) {
2311                 if (!unlink(patch->old_name) && rmdir_empty) {
2312                         char *name = xstrdup(patch->old_name);
2313                         char *end = strrchr(name, '/');
2314                         while (end) {
2315                                 *end = 0;
2316                                 if (rmdir(name))
2317                                         break;
2318                                 end = strrchr(name, '/');
2319                         }
2320                         free(name);
2321                 }
2322         }
2323 }
2324
2325 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2326 {
2327         struct stat st;
2328         struct cache_entry *ce;
2329         int namelen = strlen(path);
2330         unsigned ce_size = cache_entry_size(namelen);
2331
2332         if (!write_index)
2333                 return;
2334
2335         ce = xcalloc(1, ce_size);
2336         memcpy(ce->name, path, namelen);
2337         ce->ce_mode = create_ce_mode(mode);
2338         ce->ce_flags = htons(namelen);
2339         if (!cached) {
2340                 if (lstat(path, &st) < 0)
2341                         die("unable to stat newly created file %s", path);
2342                 fill_stat_cache_info(ce, &st);
2343         }
2344         if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2345                 die("unable to create backing store for newly created file %s", path);
2346         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2347                 die("unable to add cache entry for %s", path);
2348 }
2349
2350 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2351 {
2352         int fd;
2353         char *nbuf;
2354         unsigned long nsize;
2355
2356         if (S_ISLNK(mode))
2357                 /* Although buf:size is counted string, it also is NUL
2358                  * terminated.
2359                  */
2360                 return symlink(buf, path);
2361         nsize = size;
2362         nbuf = (char *) buf;
2363         if (convert_to_working_tree(path, &nbuf, &nsize)) {
2364                 free((char *) buf);
2365                 buf = nbuf;
2366                 size = nsize;
2367         }
2368
2369         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2370         if (fd < 0)
2371                 return -1;
2372         while (size) {
2373                 int written = xwrite(fd, buf, size);
2374                 if (written < 0)
2375                         die("writing file %s: %s", path, strerror(errno));
2376                 if (!written)
2377                         die("out of space writing file %s", path);
2378                 buf += written;
2379                 size -= written;
2380         }
2381         if (close(fd) < 0)
2382                 die("closing file %s: %s", path, strerror(errno));
2383         return 0;
2384 }
2385
2386 /*
2387  * We optimistically assume that the directories exist,
2388  * which is true 99% of the time anyway. If they don't,
2389  * we create them and try again.
2390  */
2391 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2392 {
2393         if (cached)
2394                 return;
2395         if (!try_create_file(path, mode, buf, size))
2396                 return;
2397
2398         if (errno == ENOENT) {
2399                 if (safe_create_leading_directories(path))
2400                         return;
2401                 if (!try_create_file(path, mode, buf, size))
2402                         return;
2403         }
2404
2405         if (errno == EEXIST || errno == EACCES) {
2406                 /* We may be trying to create a file where a directory
2407                  * used to be.
2408                  */
2409                 struct stat st;
2410                 errno = 0;
2411                 if (!lstat(path, &st) && S_ISDIR(st.st_mode) && !rmdir(path))
2412                         errno = EEXIST;
2413         }
2414
2415         if (errno == EEXIST) {
2416                 unsigned int nr = getpid();
2417
2418                 for (;;) {
2419                         const char *newpath;
2420                         newpath = mkpath("%s~%u", path, nr);
2421                         if (!try_create_file(newpath, mode, buf, size)) {
2422                                 if (!rename(newpath, path))
2423                                         return;
2424                                 unlink(newpath);
2425                                 break;
2426                         }
2427                         if (errno != EEXIST)
2428                                 break;
2429                         ++nr;
2430                 }
2431         }
2432         die("unable to write file %s mode %o", path, mode);
2433 }
2434
2435 static void create_file(struct patch *patch)
2436 {
2437         char *path = patch->new_name;
2438         unsigned mode = patch->new_mode;
2439         unsigned long size = patch->resultsize;
2440         char *buf = patch->result;
2441
2442         if (!mode)
2443                 mode = S_IFREG | 0644;
2444         create_one_file(path, mode, buf, size);
2445         add_index_file(path, mode, buf, size);
2446         cache_tree_invalidate_path(active_cache_tree, path);
2447 }
2448
2449 /* phase zero is to remove, phase one is to create */
2450 static void write_out_one_result(struct patch *patch, int phase)
2451 {
2452         if (patch->is_delete > 0) {
2453                 if (phase == 0)
2454                         remove_file(patch, 1);
2455                 return;
2456         }
2457         if (patch->is_new > 0 || patch->is_copy) {
2458                 if (phase == 1)
2459                         create_file(patch);
2460                 return;
2461         }
2462         /*
2463          * Rename or modification boils down to the same
2464          * thing: remove the old, write the new
2465          */
2466         if (phase == 0)
2467                 remove_file(patch, 0);
2468         if (phase == 1)
2469                 create_file(patch);
2470 }
2471
2472 static int write_out_one_reject(struct patch *patch)
2473 {
2474         FILE *rej;
2475         char namebuf[PATH_MAX];
2476         struct fragment *frag;
2477         int cnt = 0;
2478
2479         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2480                 if (!frag->rejected)
2481                         continue;
2482                 cnt++;
2483         }
2484
2485         if (!cnt) {
2486                 if (apply_verbosely)
2487                         say_patch_name(stderr,
2488                                        "Applied patch ", patch, " cleanly.\n");
2489                 return 0;
2490         }
2491
2492         /* This should not happen, because a removal patch that leaves
2493          * contents are marked "rejected" at the patch level.
2494          */
2495         if (!patch->new_name)
2496                 die("internal error");
2497
2498         /* Say this even without --verbose */
2499         say_patch_name(stderr, "Applying patch ", patch, " with");
2500         fprintf(stderr, " %d rejects...\n", cnt);
2501
2502         cnt = strlen(patch->new_name);
2503         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2504                 cnt = ARRAY_SIZE(namebuf) - 5;
2505                 fprintf(stderr,
2506                         "warning: truncating .rej filename to %.*s.rej",
2507                         cnt - 1, patch->new_name);
2508         }
2509         memcpy(namebuf, patch->new_name, cnt);
2510         memcpy(namebuf + cnt, ".rej", 5);
2511
2512         rej = fopen(namebuf, "w");
2513         if (!rej)
2514                 return error("cannot open %s: %s", namebuf, strerror(errno));
2515
2516         /* Normal git tools never deal with .rej, so do not pretend
2517          * this is a git patch by saying --git nor give extended
2518          * headers.  While at it, maybe please "kompare" that wants
2519          * the trailing TAB and some garbage at the end of line ;-).
2520          */
2521         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2522                 patch->new_name, patch->new_name);
2523         for (cnt = 1, frag = patch->fragments;
2524              frag;
2525              cnt++, frag = frag->next) {
2526                 if (!frag->rejected) {
2527                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2528                         continue;
2529                 }
2530                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2531                 fprintf(rej, "%.*s", frag->size, frag->patch);
2532                 if (frag->patch[frag->size-1] != '\n')
2533                         fputc('\n', rej);
2534         }
2535         fclose(rej);
2536         return -1;
2537 }
2538
2539 static int write_out_results(struct patch *list, int skipped_patch)
2540 {
2541         int phase;
2542         int errs = 0;
2543         struct patch *l;
2544
2545         if (!list && !skipped_patch)
2546                 return error("No changes");
2547
2548         for (phase = 0; phase < 2; phase++) {
2549                 l = list;
2550                 while (l) {
2551                         if (l->rejected)
2552                                 errs = 1;
2553                         else {
2554                                 write_out_one_result(l, phase);
2555                                 if (phase == 1 && write_out_one_reject(l))
2556                                         errs = 1;
2557                         }
2558                         l = l->next;
2559                 }
2560         }
2561         return errs;
2562 }
2563
2564 static struct lock_file lock_file;
2565
2566 static struct excludes {
2567         struct excludes *next;
2568         const char *path;
2569 } *excludes;
2570
2571 static int use_patch(struct patch *p)
2572 {
2573         const char *pathname = p->new_name ? p->new_name : p->old_name;
2574         struct excludes *x = excludes;
2575         while (x) {
2576                 if (fnmatch(x->path, pathname, 0) == 0)
2577                         return 0;
2578                 x = x->next;
2579         }
2580         if (0 < prefix_length) {
2581                 int pathlen = strlen(pathname);
2582                 if (pathlen <= prefix_length ||
2583                     memcmp(prefix, pathname, prefix_length))
2584                         return 0;
2585         }
2586         return 1;
2587 }
2588
2589 static void prefix_one(char **name)
2590 {
2591         char *old_name = *name;
2592         if (!old_name)
2593                 return;
2594         *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
2595         free(old_name);
2596 }
2597
2598 static void prefix_patches(struct patch *p)
2599 {
2600         if (!prefix || p->is_toplevel_relative)
2601                 return;
2602         for ( ; p; p = p->next) {
2603                 if (p->new_name == p->old_name) {
2604                         char *prefixed = p->new_name;
2605                         prefix_one(&prefixed);
2606                         p->new_name = p->old_name = prefixed;
2607                 }
2608                 else {
2609                         prefix_one(&p->new_name);
2610                         prefix_one(&p->old_name);
2611                 }
2612         }
2613 }
2614
2615 static int apply_patch(int fd, const char *filename, int inaccurate_eof)
2616 {
2617         unsigned long offset, size;
2618         char *buffer = read_patch_file(fd, &size);
2619         struct patch *list = NULL, **listp = &list;
2620         int skipped_patch = 0;
2621
2622         patch_input_file = filename;
2623         if (!buffer)
2624                 return -1;
2625         offset = 0;
2626         while (size > 0) {
2627                 struct patch *patch;
2628                 int nr;
2629
2630                 patch = xcalloc(1, sizeof(*patch));
2631                 patch->inaccurate_eof = inaccurate_eof;
2632                 nr = parse_chunk(buffer + offset, size, patch);
2633                 if (nr < 0)
2634                         break;
2635                 if (apply_in_reverse)
2636                         reverse_patches(patch);
2637                 if (prefix)
2638                         prefix_patches(patch);
2639                 if (use_patch(patch)) {
2640                         patch_stats(patch);
2641                         *listp = patch;
2642                         listp = &patch->next;
2643                 }
2644                 else {
2645                         /* perhaps free it a bit better? */
2646                         free(patch);
2647                         skipped_patch++;
2648                 }
2649                 offset += nr;
2650                 size -= nr;
2651         }
2652
2653         if (whitespace_error && (new_whitespace == error_on_whitespace))
2654                 apply = 0;
2655
2656         write_index = check_index && apply;
2657         if (write_index && newfd < 0)
2658                 newfd = hold_lock_file_for_update(&lock_file,
2659                                                   get_index_file(), 1);
2660         if (check_index) {
2661                 if (read_cache() < 0)
2662                         die("unable to read index file");
2663         }
2664
2665         if ((check || apply) &&
2666             check_patch_list(list) < 0 &&
2667             !apply_with_reject)
2668                 exit(1);
2669
2670         if (apply && write_out_results(list, skipped_patch))
2671                 exit(1);
2672
2673         if (show_index_info)
2674                 show_index_list(list);
2675
2676         if (diffstat)
2677                 stat_patch_list(list);
2678
2679         if (numstat)
2680                 numstat_patch_list(list);
2681
2682         if (summary)
2683                 summary_patch_list(list);
2684
2685         free(buffer);
2686         return 0;
2687 }
2688
2689 static int git_apply_config(const char *var, const char *value)
2690 {
2691         if (!strcmp(var, "apply.whitespace")) {
2692                 apply_default_whitespace = xstrdup(value);
2693                 return 0;
2694         }
2695         return git_default_config(var, value);
2696 }
2697
2698
2699 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
2700 {
2701         int i;
2702         int read_stdin = 1;
2703         int inaccurate_eof = 0;
2704         int errs = 0;
2705         int is_not_gitdir = 0;
2706
2707         const char *whitespace_option = NULL;
2708
2709         prefix = setup_git_directory_gently(&is_not_gitdir);
2710         prefix_length = prefix ? strlen(prefix) : 0;
2711         git_config(git_apply_config);
2712         if (apply_default_whitespace)
2713                 parse_whitespace_option(apply_default_whitespace);
2714
2715         for (i = 1; i < argc; i++) {
2716                 const char *arg = argv[i];
2717                 char *end;
2718                 int fd;
2719
2720                 if (!strcmp(arg, "-")) {
2721                         errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2722                         read_stdin = 0;
2723                         continue;
2724                 }
2725                 if (!prefixcmp(arg, "--exclude=")) {
2726                         struct excludes *x = xmalloc(sizeof(*x));
2727                         x->path = arg + 10;
2728                         x->next = excludes;
2729                         excludes = x;
2730                         continue;
2731                 }
2732                 if (!prefixcmp(arg, "-p")) {
2733                         p_value = atoi(arg + 2);
2734                         p_value_known = 1;
2735                         continue;
2736                 }
2737                 if (!strcmp(arg, "--no-add")) {
2738                         no_add = 1;
2739                         continue;
2740                 }
2741                 if (!strcmp(arg, "--stat")) {
2742                         apply = 0;
2743                         diffstat = 1;
2744                         continue;
2745                 }
2746                 if (!strcmp(arg, "--allow-binary-replacement") ||
2747                     !strcmp(arg, "--binary")) {
2748                         continue; /* now no-op */
2749                 }
2750                 if (!strcmp(arg, "--numstat")) {
2751                         apply = 0;
2752                         numstat = 1;
2753                         continue;
2754                 }
2755                 if (!strcmp(arg, "--summary")) {
2756                         apply = 0;
2757                         summary = 1;
2758                         continue;
2759                 }
2760                 if (!strcmp(arg, "--check")) {
2761                         apply = 0;
2762                         check = 1;
2763                         continue;
2764                 }
2765                 if (!strcmp(arg, "--index")) {
2766                         if (is_not_gitdir)
2767                                 die("--index outside a repository");
2768                         check_index = 1;
2769                         continue;
2770                 }
2771                 if (!strcmp(arg, "--cached")) {
2772                         if (is_not_gitdir)
2773                                 die("--cached outside a repository");
2774                         check_index = 1;
2775                         cached = 1;
2776                         continue;
2777                 }
2778                 if (!strcmp(arg, "--apply")) {
2779                         apply = 1;
2780                         continue;
2781                 }
2782                 if (!strcmp(arg, "--index-info")) {
2783                         apply = 0;
2784                         show_index_info = 1;
2785                         continue;
2786                 }
2787                 if (!strcmp(arg, "-z")) {
2788                         line_termination = 0;
2789                         continue;
2790                 }
2791                 if (!prefixcmp(arg, "-C")) {
2792                         p_context = strtoul(arg + 2, &end, 0);
2793                         if (*end != '\0')
2794                                 die("unrecognized context count '%s'", arg + 2);
2795                         continue;
2796                 }
2797                 if (!prefixcmp(arg, "--whitespace=")) {
2798                         whitespace_option = arg + 13;
2799                         parse_whitespace_option(arg + 13);
2800                         continue;
2801                 }
2802                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
2803                         apply_in_reverse = 1;
2804                         continue;
2805                 }
2806                 if (!strcmp(arg, "--unidiff-zero")) {
2807                         unidiff_zero = 1;
2808                         continue;
2809                 }
2810                 if (!strcmp(arg, "--reject")) {
2811                         apply = apply_with_reject = apply_verbosely = 1;
2812                         continue;
2813                 }
2814                 if (!strcmp(arg, "--verbose")) {
2815                         apply_verbosely = 1;
2816                         continue;
2817                 }
2818                 if (!strcmp(arg, "--inaccurate-eof")) {
2819                         inaccurate_eof = 1;
2820                         continue;
2821                 }
2822                 if (0 < prefix_length)
2823                         arg = prefix_filename(prefix, prefix_length, arg);
2824
2825                 fd = open(arg, O_RDONLY);
2826                 if (fd < 0)
2827                         usage(apply_usage);
2828                 read_stdin = 0;
2829                 set_default_whitespace_mode(whitespace_option);
2830                 errs |= apply_patch(fd, arg, inaccurate_eof);
2831                 close(fd);
2832         }
2833         set_default_whitespace_mode(whitespace_option);
2834         if (read_stdin)
2835                 errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2836         if (whitespace_error) {
2837                 if (squelch_whitespace_errors &&
2838                     squelch_whitespace_errors < whitespace_error) {
2839                         int squelched =
2840                                 whitespace_error - squelch_whitespace_errors;
2841                         fprintf(stderr, "warning: squelched %d "
2842                                 "whitespace error%s\n",
2843                                 squelched,
2844                                 squelched == 1 ? "" : "s");
2845                 }
2846                 if (new_whitespace == error_on_whitespace)
2847                         die("%d line%s add%s trailing whitespaces.",
2848                             whitespace_error,
2849                             whitespace_error == 1 ? "" : "s",
2850                             whitespace_error == 1 ? "s" : "");
2851                 if (applied_after_stripping)
2852                         fprintf(stderr, "warning: %d line%s applied after"
2853                                 " stripping trailing whitespaces.\n",
2854                                 applied_after_stripping,
2855                                 applied_after_stripping == 1 ? "" : "s");
2856                 else if (whitespace_error)
2857                         fprintf(stderr, "warning: %d line%s add%s trailing"
2858                                 " whitespaces.\n",
2859                                 whitespace_error,
2860                                 whitespace_error == 1 ? "" : "s",
2861                                 whitespace_error == 1 ? "s" : "");
2862         }
2863
2864         if (write_index) {
2865                 if (write_cache(newfd, active_cache, active_nr) ||
2866                     close(newfd) || commit_lock_file(&lock_file))
2867                         die("Unable to write new index file");
2868         }
2869
2870         return !!errs;
2871 }