builtin-apply.c

   1 /*
   2  * apply.c
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  *
   6  * This applies patches on top of some (arbitrary) version of the SCM.
   7  *
   8  */
   9 #include <fnmatch.h>
  10 #include "cache.h"
  11 #include "cache-tree.h"
  12 #include "quote.h"
  13 #include "blob.h"
  14 #include "delta.h"
  15 #include "builtin.h"
  16
  17 /*
  18  *  --check turns on checking that the working tree matches the
  19  *    files that are being modified, but doesn't apply the patch
  20  *  --stat does just a diffstat, and doesn't actually apply
  21  *  --numstat does numeric diffstat, and doesn't actually apply
  22  *  --index-info shows the old and new index info for paths if available.
  23  *  --index updates the cache as well.
  24  *  --cached updates only the cache without ever touching the working tree.
  25  */
  26 static const char *prefix;
  27 static int prefix_length = -1;
  28 static int newfd = -1;
  29
  30 static int unidiff_zero;
  31 static int p_value = 1;
  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 = -1;
  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_rename, is_copy, is_new, is_delete, is_binary;
 144         int rejected;
 145         unsigned long deflate_origlen;
 146         int lines_added, lines_deleted;
 147         int score;
 148         int inaccurate_eof:1;
 149         struct fragment *fragments;
 150         char *result;
 151         unsigned long resultsize;
 152         char old_sha1_prefix[41];
 153         char new_sha1_prefix[41];
 154         struct patch *next;
 155 };
 156
 157 static void say_patch_name(FILE *output, const char *pre, struct patch *patch, const char *post)
 158 {
 159         fputs(pre, output);
 160         if (patch->old_name && patch->new_name &&
 161             strcmp(patch->old_name, patch->new_name)) {
 162                 write_name_quoted(NULL, 0, patch->old_name, 1, output);
 163                 fputs(" => ", output);
 164                 write_name_quoted(NULL, 0, patch->new_name, 1, output);
 165         }
 166         else {
 167                 const char *n = patch->new_name;
 168                 if (!n)
 169                         n = patch->old_name;
 170                 write_name_quoted(NULL, 0, n, 1, output);
 171         }
 172         fputs(post, output);
 173 }
 174
 175 #define CHUNKSIZE (8192)
 176 #define SLOP (16)
 177
 178 static void *read_patch_file(int fd, unsigned long *sizep)
 179 {
 180         unsigned long size = 0, alloc = CHUNKSIZE;
 181         void *buffer = xmalloc(alloc);
 182
 183         for (;;) {
 184                 int nr = alloc - size;
 185                 if (nr < 1024) {
 186                         alloc += CHUNKSIZE;
 187                         buffer = xrealloc(buffer, alloc);
 188                         nr = alloc - size;
 189                 }
 190                 nr = xread(fd, (char *) buffer + size, nr);
 191                 if (!nr)
 192                         break;
 193                 if (nr < 0)
 194                         die("git-apply: read returned %s", strerror(errno));
 195                 size += nr;
 196         }
 197         *sizep = size;
 198
 199         /*
 200          * Make sure that we have some slop in the buffer
 201          * so that we can do speculative "memcmp" etc, and
 202          * see to it that it is NUL-filled.
 203          */
 204         if (alloc < size + SLOP)
 205                 buffer = xrealloc(buffer, size + SLOP);
 206         memset((char *) buffer + size, 0, SLOP);
 207         return buffer;
 208 }
 209
 210 static unsigned long linelen(const char *buffer, unsigned long size)
 211 {
 212         unsigned long len = 0;
 213         while (size--) {
 214                 len++;
 215                 if (*buffer++ == '\n')
 216                         break;
 217         }
 218         return len;
 219 }
 220
 221 static int is_dev_null(const char *str)
 222 {
 223         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
 224 }
 225
 226 #define TERM_SPACE      1
 227 #define TERM_TAB        2
 228
 229 static int name_terminate(const char *name, int namelen, int c, int terminate)
 230 {
 231         if (c == ' ' && !(terminate & TERM_SPACE))
 232                 return 0;
 233         if (c == '\t' && !(terminate & TERM_TAB))
 234                 return 0;
 235
 236         return 1;
 237 }
 238
 239 static char * find_name(const char *line, char *def, int p_value, int terminate)
 240 {
 241         int len;
 242         const char *start = line;
 243         char *name;
 244
 245         if (*line == '"') {
 246                 /* Proposed "new-style" GNU patch/diff format; see
 247                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
 248                  */
 249                 name = unquote_c_style(line, NULL);
 250                 if (name) {
 251                         char *cp = name;
 252                         while (p_value) {
 253                                 cp = strchr(name, '/');
 254                                 if (!cp)
 255                                         break;
 256                                 cp++;
 257                                 p_value--;
 258                         }
 259                         if (cp) {
 260                                 /* name can later be freed, so we need
 261                                  * to memmove, not just return cp
 262                                  */
 263                                 memmove(name, cp, strlen(cp) + 1);
 264                                 free(def);
 265                                 return name;
 266                         }
 267                         else {
 268                                 free(name);
 269                                 name = NULL;
 270                         }
 271                 }
 272         }
 273
 274         for (;;) {
 275                 char c = *line;
 276
 277                 if (isspace(c)) {
 278                         if (c == '\n')
 279                                 break;
 280                         if (name_terminate(start, line-start, c, terminate))
 281                                 break;
 282                 }
 283                 line++;
 284                 if (c == '/' && !--p_value)
 285                         start = line;
 286         }
 287         if (!start)
 288                 return def;
 289         len = line - start;
 290         if (!len)
 291                 return def;
 292
 293         /*
 294          * Generally we prefer the shorter name, especially
 295          * if the other one is just a variation of that with
 296          * something else tacked on to the end (ie "file.orig"
 297          * or "file~").
 298          */
 299         if (def) {
 300                 int deflen = strlen(def);
 301                 if (deflen < len && !strncmp(start, def, deflen))
 302                         return def;
 303         }
 304
 305         name = xmalloc(len + 1);
 306         memcpy(name, start, len);
 307         name[len] = 0;
 308         free(def);
 309         return name;
 310 }
 311
 312 /*
 313  * Get the name etc info from the --/+++ lines of a traditional patch header
 314  *
 315  * NOTE! This hardcodes "-p1" behaviour in filename detection.
 316  *
 317  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 318  * files, we can happily check the index for a match, but for creating a
 319  * new file we should try to match whatever "patch" does. I have no idea.
 320  */
 321 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
 322 {
 323         char *name;
 324
 325         first += 4;     /* skip "--- " */
 326         second += 4;    /* skip "+++ " */
 327         if (is_dev_null(first)) {
 328                 patch->is_new = 1;
 329                 patch->is_delete = 0;
 330                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
 331                 patch->new_name = name;
 332         } else if (is_dev_null(second)) {
 333                 patch->is_new = 0;
 334                 patch->is_delete = 1;
 335                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 336                 patch->old_name = name;
 337         } else {
 338                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 339                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
 340                 patch->old_name = patch->new_name = name;
 341         }
 342         if (!name)
 343                 die("unable to find filename in patch at line %d", linenr);
 344 }
 345
 346 static int gitdiff_hdrend(const char *line, struct patch *patch)
 347 {
 348         return -1;
 349 }
 350
 351 /*
 352  * We're anal about diff header consistency, to make
 353  * sure that we don't end up having strange ambiguous
 354  * patches floating around.
 355  *
 356  * As a result, gitdiff_{old|new}name() will check
 357  * their names against any previous information, just
 358  * to make sure..
 359  */
 360 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
 361 {
 362         if (!orig_name && !isnull)
 363                 return find_name(line, NULL, 1, 0);
 364
 365         if (orig_name) {
 366                 int len;
 367                 const char *name;
 368                 char *another;
 369                 name = orig_name;
 370                 len = strlen(name);
 371                 if (isnull)
 372                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
 373                 another = find_name(line, NULL, 1, 0);
 374                 if (!another || memcmp(another, name, len))
 375                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
 376                 free(another);
 377                 return orig_name;
 378         }
 379         else {
 380                 /* expect "/dev/null" */
 381                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
 382                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
 383                 return NULL;
 384         }
 385 }
 386
 387 static int gitdiff_oldname(const char *line, struct patch *patch)
 388 {
 389         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
 390         return 0;
 391 }
 392
 393 static int gitdiff_newname(const char *line, struct patch *patch)
 394 {
 395         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
 396         return 0;
 397 }
 398
 399 static int gitdiff_oldmode(const char *line, struct patch *patch)
 400 {
 401         patch->old_mode = strtoul(line, NULL, 8);
 402         return 0;
 403 }
 404
 405 static int gitdiff_newmode(const char *line, struct patch *patch)
 406 {
 407         patch->new_mode = strtoul(line, NULL, 8);
 408         return 0;
 409 }
 410
 411 static int gitdiff_delete(const char *line, struct patch *patch)
 412 {
 413         patch->is_delete = 1;
 414         patch->old_name = patch->def_name;
 415         return gitdiff_oldmode(line, patch);
 416 }
 417
 418 static int gitdiff_newfile(const char *line, struct patch *patch)
 419 {
 420         patch->is_new = 1;
 421         patch->new_name = patch->def_name;
 422         return gitdiff_newmode(line, patch);
 423 }
 424
 425 static int gitdiff_copysrc(const char *line, struct patch *patch)
 426 {
 427         patch->is_copy = 1;
 428         patch->old_name = find_name(line, NULL, 0, 0);
 429         return 0;
 430 }
 431
 432 static int gitdiff_copydst(const char *line, struct patch *patch)
 433 {
 434         patch->is_copy = 1;
 435         patch->new_name = find_name(line, NULL, 0, 0);
 436         return 0;
 437 }
 438
 439 static int gitdiff_renamesrc(const char *line, struct patch *patch)
 440 {
 441         patch->is_rename = 1;
 442         patch->old_name = find_name(line, NULL, 0, 0);
 443         return 0;
 444 }
 445
 446 static int gitdiff_renamedst(const char *line, struct patch *patch)
 447 {
 448         patch->is_rename = 1;
 449         patch->new_name = find_name(line, NULL, 0, 0);
 450         return 0;
 451 }
 452
 453 static int gitdiff_similarity(const char *line, struct patch *patch)
 454 {
 455         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 456                 patch->score = 0;
 457         return 0;
 458 }
 459
 460 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
 461 {
 462         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 463                 patch->score = 0;
 464         return 0;
 465 }
 466
 467 static int gitdiff_index(const char *line, struct patch *patch)
 468 {
 469         /* index line is N hexadecimal, "..", N hexadecimal,
 470          * and optional space with octal mode.
 471          */
 472         const char *ptr, *eol;
 473         int len;
 474
 475         ptr = strchr(line, '.');
 476         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
 477                 return 0;
 478         len = ptr - line;
 479         memcpy(patch->old_sha1_prefix, line, len);
 480         patch->old_sha1_prefix[len] = 0;
 481
 482         line = ptr + 2;
 483         ptr = strchr(line, ' ');
 484         eol = strchr(line, '\n');
 485
 486         if (!ptr || eol < ptr)
 487                 ptr = eol;
 488         len = ptr - line;
 489
 490         if (40 < len)
 491                 return 0;
 492         memcpy(patch->new_sha1_prefix, line, len);
 493         patch->new_sha1_prefix[len] = 0;
 494         if (*ptr == ' ')
 495                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
 496         return 0;
 497 }
 498
 499 /*
 500  * This is normal for a diff that doesn't change anything: we'll fall through
 501  * into the next diff. Tell the parser to break out.
 502  */
 503 static int gitdiff_unrecognized(const char *line, struct patch *patch)
 504 {
 505         return -1;
 506 }
 507
 508 static const char *stop_at_slash(const char *line, int llen)
 509 {
 510         int i;
 511
 512         for (i = 0; i < llen; i++) {
 513                 int ch = line[i];
 514                 if (ch == '/')
 515                         return line + i;
 516         }
 517         return NULL;
 518 }
 519
 520 /* This is to extract the same name that appears on "diff --git"
 521  * line.  We do not find and return anything if it is a rename
 522  * patch, and it is OK because we will find the name elsewhere.
 523  * We need to reliably find name only when it is mode-change only,
 524  * creation or deletion of an empty file.  In any of these cases,
 525  * both sides are the same name under a/ and b/ respectively.
 526  */
 527 static char *git_header_name(char *line, int llen)
 528 {
 529         int len;
 530         const char *name;
 531         const char *second = NULL;
 532
 533         line += strlen("diff --git ");
 534         llen -= strlen("diff --git ");
 535
 536         if (*line == '"') {
 537                 const char *cp;
 538                 char *first = unquote_c_style(line, &second);
 539                 if (!first)
 540                         return NULL;
 541
 542                 /* advance to the first slash */
 543                 cp = stop_at_slash(first, strlen(first));
 544                 if (!cp || cp == first) {
 545                         /* we do not accept absolute paths */
 546                 free_first_and_fail:
 547                         free(first);
 548                         return NULL;
 549                 }
 550                 len = strlen(cp+1);
 551                 memmove(first, cp+1, len+1); /* including NUL */
 552
 553                 /* second points at one past closing dq of name.
 554                  * find the second name.
 555                  */
 556                 while ((second < line + llen) && isspace(*second))
 557                         second++;
 558
 559                 if (line + llen <= second)
 560                         goto free_first_and_fail;
 561                 if (*second == '"') {
 562                         char *sp = unquote_c_style(second, NULL);
 563                         if (!sp)
 564                                 goto free_first_and_fail;
 565                         cp = stop_at_slash(sp, strlen(sp));
 566                         if (!cp || cp == sp) {
 567                         free_both_and_fail:
 568                                 free(sp);
 569                                 goto free_first_and_fail;
 570                         }
 571                         /* They must match, otherwise ignore */
 572                         if (strcmp(cp+1, first))
 573                                 goto free_both_and_fail;
 574                         free(sp);
 575                         return first;
 576                 }
 577
 578                 /* unquoted second */
 579                 cp = stop_at_slash(second, line + llen - second);
 580                 if (!cp || cp == second)
 581                         goto free_first_and_fail;
 582                 cp++;
 583                 if (line + llen - cp != len + 1 ||
 584                     memcmp(first, cp, len))
 585                         goto free_first_and_fail;
 586                 return first;
 587         }
 588
 589         /* unquoted first name */
 590         name = stop_at_slash(line, llen);
 591         if (!name || name == line)
 592                 return NULL;
 593
 594         name++;
 595
 596         /* since the first name is unquoted, a dq if exists must be
 597          * the beginning of the second name.
 598          */
 599         for (second = name; second < line + llen; second++) {
 600                 if (*second == '"') {
 601                         const char *cp = second;
 602                         const char *np;
 603                         char *sp = unquote_c_style(second, NULL);
 604
 605                         if (!sp)
 606                                 return NULL;
 607                         np = stop_at_slash(sp, strlen(sp));
 608                         if (!np || np == sp) {
 609                         free_second_and_fail:
 610                                 free(sp);
 611                                 return NULL;
 612                         }
 613                         np++;
 614                         len = strlen(np);
 615                         if (len < cp - name &&
 616                             !strncmp(np, name, len) &&
 617                             isspace(name[len])) {
 618                                 /* Good */
 619                                 memmove(sp, np, len + 1);
 620                                 return sp;
 621                         }
 622                         goto free_second_and_fail;
 623                 }
 624         }
 625
 626         /*
 627          * Accept a name only if it shows up twice, exactly the same
 628          * form.
 629          */
 630         for (len = 0 ; ; len++) {
 631                 switch (name[len]) {
 632                 default:
 633                         continue;
 634                 case '\n':
 635                         return NULL;
 636                 case '\t': case ' ':
 637                         second = name+len;
 638                         for (;;) {
 639                                 char c = *second++;
 640                                 if (c == '\n')
 641                                         return NULL;
 642                                 if (c == '/')
 643                                         break;
 644                         }
 645                         if (second[len] == '\n' && !memcmp(name, second, len)) {
 646                                 char *ret = xmalloc(len + 1);
 647                                 memcpy(ret, name, len);
 648                                 ret[len] = 0;
 649                                 return ret;
 650                         }
 651                 }
 652         }
 653         return NULL;
 654 }
 655
 656 /* Verify that we recognize the lines following a git header */
 657 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
 658 {
 659         unsigned long offset;
 660
 661         /* A git diff has explicit new/delete information, so we don't guess */
 662         patch->is_new = 0;
 663         patch->is_delete = 0;
 664
 665         /*
 666          * Some things may not have the old name in the
 667          * rest of the headers anywhere (pure mode changes,
 668          * or removing or adding empty files), so we get
 669          * the default name from the header.
 670          */
 671         patch->def_name = git_header_name(line, len);
 672
 673         line += len;
 674         size -= len;
 675         linenr++;
 676         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
 677                 static const struct opentry {
 678                         const char *str;
 679                         int (*fn)(const char *, struct patch *);
 680                 } optable[] = {
 681                         { "@@ -", gitdiff_hdrend },
 682                         { "--- ", gitdiff_oldname },
 683                         { "+++ ", gitdiff_newname },
 684                         { "old mode ", gitdiff_oldmode },
 685                         { "new mode ", gitdiff_newmode },
 686                         { "deleted file mode ", gitdiff_delete },
 687                         { "new file mode ", gitdiff_newfile },
 688                         { "copy from ", gitdiff_copysrc },
 689                         { "copy to ", gitdiff_copydst },
 690                         { "rename old ", gitdiff_renamesrc },
 691                         { "rename new ", gitdiff_renamedst },
 692                         { "rename from ", gitdiff_renamesrc },
 693                         { "rename to ", gitdiff_renamedst },
 694                         { "similarity index ", gitdiff_similarity },
 695                         { "dissimilarity index ", gitdiff_dissimilarity },
 696                         { "index ", gitdiff_index },
 697                         { "", gitdiff_unrecognized },
 698                 };
 699                 int i;
 700
 701                 len = linelen(line, size);
 702                 if (!len || line[len-1] != '\n')
 703                         break;
 704                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
 705                         const struct opentry *p = optable + i;
 706                         int oplen = strlen(p->str);
 707                         if (len < oplen || memcmp(p->str, line, oplen))
 708                                 continue;
 709                         if (p->fn(line + oplen, patch) < 0)
 710                                 return offset;
 711                         break;
 712                 }
 713         }
 714
 715         return offset;
 716 }
 717
 718 static int parse_num(const char *line, unsigned long *p)
 719 {
 720         char *ptr;
 721
 722         if (!isdigit(*line))
 723                 return 0;
 724         *p = strtoul(line, &ptr, 10);
 725         return ptr - line;
 726 }
 727
 728 static int parse_range(const char *line, int len, int offset, const char *expect,
 729                         unsigned long *p1, unsigned long *p2)
 730 {
 731         int digits, ex;
 732
 733         if (offset < 0 || offset >= len)
 734                 return -1;
 735         line += offset;
 736         len -= offset;
 737
 738         digits = parse_num(line, p1);
 739         if (!digits)
 740                 return -1;
 741
 742         offset += digits;
 743         line += digits;
 744         len -= digits;
 745
 746         *p2 = 1;
 747         if (*line == ',') {
 748                 digits = parse_num(line+1, p2);
 749                 if (!digits)
 750                         return -1;
 751
 752                 offset += digits+1;
 753                 line += digits+1;
 754                 len -= digits+1;
 755         }
 756
 757         ex = strlen(expect);
 758         if (ex > len)
 759                 return -1;
 760         if (memcmp(line, expect, ex))
 761                 return -1;
 762
 763         return offset + ex;
 764 }
 765
 766 /*
 767  * Parse a unified diff fragment header of the
 768  * form "@@ -a,b +c,d @@"
 769  */
 770 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
 771 {
 772         int offset;
 773
 774         if (!len || line[len-1] != '\n')
 775                 return -1;
 776
 777         /* Figure out the number of lines in a fragment */
 778         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
 779         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 780
 781         return offset;
 782 }
 783
 784 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
 785 {
 786         unsigned long offset, len;
 787
 788         patch->is_rename = patch->is_copy = 0;
 789         patch->is_new = patch->is_delete = -1;
 790         patch->old_mode = patch->new_mode = 0;
 791         patch->old_name = patch->new_name = NULL;
 792         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
 793                 unsigned long nextlen;
 794
 795                 len = linelen(line, size);
 796                 if (!len)
 797                         break;
 798
 799                 /* Testing this early allows us to take a few shortcuts.. */
 800                 if (len < 6)
 801                         continue;
 802
 803                 /*
 804                  * Make sure we don't find any unconnected patch fragments.
 805                  * That's a sign that we didn't find a header, and that a
 806                  * patch has become corrupted/broken up.
 807                  */
 808                 if (!memcmp("@@ -", line, 4)) {
 809                         struct fragment dummy;
 810                         if (parse_fragment_header(line, len, &dummy) < 0)
 811                                 continue;
 812                         error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
 813                 }
 814
 815                 if (size < len + 6)
 816                         break;
 817
 818                 /*
 819                  * Git patch? It might not have a real patch, just a rename
 820                  * or mode change, so we handle that specially
 821                  */
 822                 if (!memcmp("diff --git ", line, 11)) {
 823                         int git_hdr_len = parse_git_header(line, len, size, patch);
 824                         if (git_hdr_len <= len)
 825                                 continue;
 826                         if (!patch->old_name && !patch->new_name) {
 827                                 if (!patch->def_name)
 828                                         die("git diff header lacks filename information (line %d)", linenr);
 829                                 patch->old_name = patch->new_name = patch->def_name;
 830                         }
 831                         *hdrsize = git_hdr_len;
 832                         return offset;
 833                 }
 834
 835                 /** --- followed by +++ ? */
 836                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
 837                         continue;
 838
 839                 /*
 840                  * We only accept unified patches, so we want it to
 841                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
 842                  * minimum
 843                  */
 844                 nextlen = linelen(line + len, size - len);
 845                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
 846                         continue;
 847
 848                 /* Ok, we'll consider it a patch */
 849                 parse_traditional_patch(line, line+len, patch);
 850                 *hdrsize = len + nextlen;
 851                 linenr += 2;
 852                 return offset;
 853         }
 854         return -1;
 855 }
 856
 857 /*
 858  * Parse a unified diff. Note that this really needs to parse each
 859  * fragment separately, since the only way to know the difference
 860  * between a "---" that is part of a patch, and a "---" that starts
 861  * the next patch is to look at the line counts..
 862  */
 863 static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
 864 {
 865         int added, deleted;
 866         int len = linelen(line, size), offset;
 867         unsigned long oldlines, newlines;
 868         unsigned long leading, trailing;
 869
 870         offset = parse_fragment_header(line, len, fragment);
 871         if (offset < 0)
 872                 return -1;
 873         oldlines = fragment->oldlines;
 874         newlines = fragment->newlines;
 875         leading = 0;
 876         trailing = 0;
 877
 878         /* Parse the thing.. */
 879         line += len;
 880         size -= len;
 881         linenr++;
 882         added = deleted = 0;
 883         for (offset = len;
 884              0 < size;
 885              offset += len, size -= len, line += len, linenr++) {
 886                 if (!oldlines && !newlines)
 887                         break;
 888                 len = linelen(line, size);
 889                 if (!len || line[len-1] != '\n')
 890                         return -1;
 891                 switch (*line) {
 892                 default:
 893                         return -1;
 894                 case ' ':
 895                         oldlines--;
 896                         newlines--;
 897                         if (!deleted && !added)
 898                                 leading++;
 899                         trailing++;
 900                         break;
 901                 case '-':
 902                         deleted++;
 903                         oldlines--;
 904                         trailing = 0;
 905                         break;
 906                 case '+':
 907                         /*
 908                          * We know len is at least two, since we have a '+' and
 909                          * we checked that the last character was a '\n' above.
 910                          * That is, an addition of an empty line would check
 911                          * the '+' here.  Sneaky...
 912                          */
 913                         if ((new_whitespace != nowarn_whitespace) &&
 914                             isspace(line[len-2])) {
 915                                 whitespace_error++;
 916                                 if (squelch_whitespace_errors &&
 917                                     squelch_whitespace_errors <
 918                                     whitespace_error)
 919                                         ;
 920                                 else {
 921                                         fprintf(stderr, "Adds trailing whitespace.\n%s:%d:%.*s\n",
 922                                                 patch_input_file,
 923                                                 linenr, len-2, line+1);
 924                                 }
 925                         }
 926                         added++;
 927                         newlines--;
 928                         trailing = 0;
 929                         break;
 930
 931                 /* We allow "\ No newline at end of file". Depending
 932                  * on locale settings when the patch was produced we
 933                  * don't know what this line looks like. The only
 934                  * thing we do know is that it begins with "\ ".
 935                  * Checking for 12 is just for sanity check -- any
 936                  * l10n of "\ No newline..." is at least that long.
 937                  */
 938                 case '\\':
 939                         if (len < 12 || memcmp(line, "\\ ", 2))
 940                                 return -1;
 941                         break;
 942                 }
 943         }
 944         if (oldlines || newlines)
 945                 return -1;
 946         fragment->leading = leading;
 947         fragment->trailing = trailing;
 948
 949         /* If a fragment ends with an incomplete line, we failed to include
 950          * it in the above loop because we hit oldlines == newlines == 0
 951          * before seeing it.
 952          */
 953         if (12 < size && !memcmp(line, "\\ ", 2))
 954                 offset += linelen(line, size);
 955
 956         patch->lines_added += added;
 957         patch->lines_deleted += deleted;
 958
 959         if (0 < patch->is_new && oldlines)
 960                 return error("new file depends on old contents");
 961         if (0 < patch->is_delete && newlines)
 962                 return error("deleted file still has contents");
 963         return offset;
 964 }
 965
 966 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
 967 {
 968         unsigned long offset = 0;
 969         unsigned long oldlines = 0, newlines = 0, context = 0;
 970         struct fragment **fragp = &patch->fragments;
 971
 972         while (size > 4 && !memcmp(line, "@@ -", 4)) {
 973                 struct fragment *fragment;
 974                 int len;
 975
 976                 fragment = xcalloc(1, sizeof(*fragment));
 977                 len = parse_fragment(line, size, patch, fragment);
 978                 if (len <= 0)
 979                         die("corrupt patch at line %d", linenr);
 980                 fragment->patch = line;
 981                 fragment->size = len;
 982                 oldlines += fragment->oldlines;
 983                 newlines += fragment->newlines;
 984                 context += fragment->leading + fragment->trailing;
 985
 986                 *fragp = fragment;
 987                 fragp = &fragment->next;
 988
 989                 offset += len;
 990                 line += len;
 991                 size -= len;
 992         }
 993
 994         /*
 995          * If something was removed (i.e. we have old-lines) it cannot
 996          * be creation, and if something was added it cannot be
 997          * deletion.  However, the reverse is not true; --unified=0
 998          * patches that only add are not necessarily creation even
 999          * though they do not have any old lines, and ones that only
1000          * delete are not necessarily deletion.
1001          *
1002          * Unfortunately, a real creation/deletion patch do _not_ have
1003          * any context line by definition, so we cannot safely tell it
1004          * apart with --unified=0 insanity.  At least if the patch has
1005          * more than one hunk it is not creation or deletion.
1006          */
1007         if (patch->is_new < 0 &&
1008             (oldlines || (patch->fragments && patch->fragments->next)))
1009                 patch->is_new = 0;
1010         if (patch->is_delete < 0 &&
1011             (newlines || (patch->fragments && patch->fragments->next)))
1012                 patch->is_delete = 0;
1013         if (!unidiff_zero || context) {
1014                 /* If the user says the patch is not generated with
1015                  * --unified=0, or if we have seen context lines,
1016                  * then not having oldlines means the patch is creation,
1017                  * and not having newlines means the patch is deletion.
1018                  */
1019                 if (patch->is_new < 0 && !oldlines)
1020                         patch->is_new = 1;
1021                 if (patch->is_delete < 0 && !newlines)
1022                         patch->is_delete = 1;
1023         }
1024
1025         if (0 < patch->is_new && oldlines)
1026                 die("new file %s depends on old contents", patch->new_name);
1027         if (0 < patch->is_delete && newlines)
1028                 die("deleted file %s still has contents", patch->old_name);
1029         if (!patch->is_delete && !newlines && context)
1030                 fprintf(stderr, "** warning: file %s becomes empty but "
1031                         "is not deleted\n", patch->new_name);
1032
1033         return offset;
1034 }
1035
1036 static inline int metadata_changes(struct patch *patch)
1037 {
1038         return  patch->is_rename > 0 ||
1039                 patch->is_copy > 0 ||
1040                 patch->is_new > 0 ||
1041                 patch->is_delete ||
1042                 (patch->old_mode && patch->new_mode &&
1043                  patch->old_mode != patch->new_mode);
1044 }
1045
1046 static char *inflate_it(const void *data, unsigned long size,
1047                         unsigned long inflated_size)
1048 {
1049         z_stream stream;
1050         void *out;
1051         int st;
1052
1053         memset(&stream, 0, sizeof(stream));
1054
1055         stream.next_in = (unsigned char *)data;
1056         stream.avail_in = size;
1057         stream.next_out = out = xmalloc(inflated_size);
1058         stream.avail_out = inflated_size;
1059         inflateInit(&stream);
1060         st = inflate(&stream, Z_FINISH);
1061         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1062                 free(out);
1063                 return NULL;
1064         }
1065         return out;
1066 }
1067
1068 static struct fragment *parse_binary_hunk(char **buf_p,
1069                                           unsigned long *sz_p,
1070                                           int *status_p,
1071                                           int *used_p)
1072 {
1073         /* Expect a line that begins with binary patch method ("literal"
1074          * or "delta"), followed by the length of data before deflating.
1075          * a sequence of 'length-byte' followed by base-85 encoded data
1076          * should follow, terminated by a newline.
1077          *
1078          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1079          * and we would limit the patch line to 66 characters,
1080          * so one line can fit up to 13 groups that would decode
1081          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1082          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1083          */
1084         int llen, used;
1085         unsigned long size = *sz_p;
1086         char *buffer = *buf_p;
1087         int patch_method;
1088         unsigned long origlen;
1089         char *data = NULL;
1090         int hunk_size = 0;
1091         struct fragment *frag;
1092
1093         llen = linelen(buffer, size);
1094         used = llen;
1095
1096         *status_p = 0;
1097
1098         if (!strncmp(buffer, "delta ", 6)) {
1099                 patch_method = BINARY_DELTA_DEFLATED;
1100                 origlen = strtoul(buffer + 6, NULL, 10);
1101         }
1102         else if (!strncmp(buffer, "literal ", 8)) {
1103                 patch_method = BINARY_LITERAL_DEFLATED;
1104                 origlen = strtoul(buffer + 8, NULL, 10);
1105         }
1106         else
1107                 return NULL;
1108
1109         linenr++;
1110         buffer += llen;
1111         while (1) {
1112                 int byte_length, max_byte_length, newsize;
1113                 llen = linelen(buffer, size);
1114                 used += llen;
1115                 linenr++;
1116                 if (llen == 1) {
1117                         /* consume the blank line */
1118                         buffer++;
1119                         size--;
1120                         break;
1121                 }
1122                 /* Minimum line is "A00000\n" which is 7-byte long,
1123                  * and the line length must be multiple of 5 plus 2.
1124                  */
1125                 if ((llen < 7) || (llen-2) % 5)
1126                         goto corrupt;
1127                 max_byte_length = (llen - 2) / 5 * 4;
1128                 byte_length = *buffer;
1129                 if ('A' <= byte_length && byte_length <= 'Z')
1130                         byte_length = byte_length - 'A' + 1;
1131                 else if ('a' <= byte_length && byte_length <= 'z')
1132                         byte_length = byte_length - 'a' + 27;
1133                 else
1134                         goto corrupt;
1135                 /* if the input length was not multiple of 4, we would
1136                  * have filler at the end but the filler should never
1137                  * exceed 3 bytes
1138                  */
1139                 if (max_byte_length < byte_length ||
1140                     byte_length <= max_byte_length - 4)
1141                         goto corrupt;
1142                 newsize = hunk_size + byte_length;
1143                 data = xrealloc(data, newsize);
1144                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1145                         goto corrupt;
1146                 hunk_size = newsize;
1147                 buffer += llen;
1148                 size -= llen;
1149         }
1150
1151         frag = xcalloc(1, sizeof(*frag));
1152         frag->patch = inflate_it(data, hunk_size, origlen);
1153         if (!frag->patch)
1154                 goto corrupt;
1155         free(data);
1156         frag->size = origlen;
1157         *buf_p = buffer;
1158         *sz_p = size;
1159         *used_p = used;
1160         frag->binary_patch_method = patch_method;
1161         return frag;
1162
1163  corrupt:
1164         free(data);
1165         *status_p = -1;
1166         error("corrupt binary patch at line %d: %.*s",
1167               linenr-1, llen-1, buffer);
1168         return NULL;
1169 }
1170
1171 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1172 {
1173         /* We have read "GIT binary patch\n"; what follows is a line
1174          * that says the patch method (currently, either "literal" or
1175          * "delta") and the length of data before deflating; a
1176          * sequence of 'length-byte' followed by base-85 encoded data
1177          * follows.
1178          *
1179          * When a binary patch is reversible, there is another binary
1180          * hunk in the same format, starting with patch method (either
1181          * "literal" or "delta") with the length of data, and a sequence
1182          * of length-byte + base-85 encoded data, terminated with another
1183          * empty line.  This data, when applied to the postimage, produces
1184          * the preimage.
1185          */
1186         struct fragment *forward;
1187         struct fragment *reverse;
1188         int status;
1189         int used, used_1;
1190
1191         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1192         if (!forward && !status)
1193                 /* there has to be one hunk (forward hunk) */
1194                 return error("unrecognized binary patch at line %d", linenr-1);
1195         if (status)
1196                 /* otherwise we already gave an error message */
1197                 return status;
1198
1199         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1200         if (reverse)
1201                 used += used_1;
1202         else if (status) {
1203                 /* not having reverse hunk is not an error, but having
1204                  * a corrupt reverse hunk is.
1205                  */
1206                 free((void*) forward->patch);
1207                 free(forward);
1208                 return status;
1209         }
1210         forward->next = reverse;
1211         patch->fragments = forward;
1212         patch->is_binary = 1;
1213         return used;
1214 }
1215
1216 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1217 {
1218         int hdrsize, patchsize;
1219         int offset = find_header(buffer, size, &hdrsize, patch);
1220
1221         if (offset < 0)
1222                 return offset;
1223
1224         patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
1225
1226         if (!patchsize) {
1227                 static const char *binhdr[] = {
1228                         "Binary files ",
1229                         "Files ",
1230                         NULL,
1231                 };
1232                 static const char git_binary[] = "GIT binary patch\n";
1233                 int i;
1234                 int hd = hdrsize + offset;
1235                 unsigned long llen = linelen(buffer + hd, size - hd);
1236
1237                 if (llen == sizeof(git_binary) - 1 &&
1238                     !memcmp(git_binary, buffer + hd, llen)) {
1239                         int used;
1240                         linenr++;
1241                         used = parse_binary(buffer + hd + llen,
1242                                             size - hd - llen, patch);
1243                         if (used)
1244                                 patchsize = used + llen;
1245                         else
1246                                 patchsize = 0;
1247                 }
1248                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1249                         for (i = 0; binhdr[i]; i++) {
1250                                 int len = strlen(binhdr[i]);
1251                                 if (len < size - hd &&
1252                                     !memcmp(binhdr[i], buffer + hd, len)) {
1253                                         linenr++;
1254                                         patch->is_binary = 1;
1255                                         patchsize = llen;
1256                                         break;
1257                                 }
1258                         }
1259                 }
1260
1261                 /* Empty patch cannot be applied if it is a text patch
1262                  * without metadata change.  A binary patch appears
1263                  * empty to us here.
1264                  */
1265                 if ((apply || check) &&
1266                     (!patch->is_binary && !metadata_changes(patch)))
1267                         die("patch with only garbage at line %d", linenr);
1268         }
1269
1270         return offset + hdrsize + patchsize;
1271 }
1272
1273 #define swap(a,b) myswap((a),(b),sizeof(a))
1274
1275 #define myswap(a, b, size) do {         \
1276         unsigned char mytmp[size];      \
1277         memcpy(mytmp, &a, size);                \
1278         memcpy(&a, &b, size);           \
1279         memcpy(&b, mytmp, size);                \
1280 } while (0)
1281
1282 static void reverse_patches(struct patch *p)
1283 {
1284         for (; p; p = p->next) {
1285                 struct fragment *frag = p->fragments;
1286
1287                 swap(p->new_name, p->old_name);
1288                 swap(p->new_mode, p->old_mode);
1289                 swap(p->is_new, p->is_delete);
1290                 swap(p->lines_added, p->lines_deleted);
1291                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1292
1293                 for (; frag; frag = frag->next) {
1294                         swap(frag->newpos, frag->oldpos);
1295                         swap(frag->newlines, frag->oldlines);
1296                 }
1297         }
1298 }
1299
1300 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1301 static const char minuses[]= "----------------------------------------------------------------------";
1302
1303 static void show_stats(struct patch *patch)
1304 {
1305         const char *prefix = "";
1306         char *name = patch->new_name;
1307         char *qname = NULL;
1308         int len, max, add, del, total;
1309
1310         if (!name)
1311                 name = patch->old_name;
1312
1313         if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
1314                 qname = xmalloc(len + 1);
1315                 quote_c_style(name, qname, NULL, 0);
1316                 name = qname;
1317         }
1318
1319         /*
1320          * "scale" the filename
1321          */
1322         len = strlen(name);
1323         max = max_len;
1324         if (max > 50)
1325                 max = 50;
1326         if (len > max) {
1327                 char *slash;
1328                 prefix = "...";
1329                 max -= 3;
1330                 name += len - max;
1331                 slash = strchr(name, '/');
1332                 if (slash)
1333                         name = slash;
1334         }
1335         len = max;
1336
1337         /*
1338          * scale the add/delete
1339          */
1340         max = max_change;
1341         if (max + len > 70)
1342                 max = 70 - len;
1343
1344         add = patch->lines_added;
1345         del = patch->lines_deleted;
1346         total = add + del;
1347
1348         if (max_change > 0) {
1349                 total = (total * max + max_change / 2) / max_change;
1350                 add = (add * max + max_change / 2) / max_change;
1351                 del = total - add;
1352         }
1353         if (patch->is_binary)
1354                 printf(" %s%-*s |  Bin\n", prefix, len, name);
1355         else
1356                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1357                        len, name, patch->lines_added + patch->lines_deleted,
1358                        add, pluses, del, minuses);
1359         free(qname);
1360 }
1361
1362 static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
1363 {
1364         int fd;
1365         unsigned long got;
1366
1367         switch (st->st_mode & S_IFMT) {
1368         case S_IFLNK:
1369                 return readlink(path, buf, size);
1370         case S_IFREG:
1371                 fd = open(path, O_RDONLY);
1372                 if (fd < 0)
1373                         return error("unable to open %s", path);
1374                 got = 0;
1375                 for (;;) {
1376                         int ret = xread(fd, (char *) buf + got, size - got);
1377                         if (ret <= 0)
1378                                 break;
1379                         got += ret;
1380                 }
1381                 close(fd);
1382                 return got;
1383
1384         default:
1385                 return -1;
1386         }
1387 }
1388
1389 static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
1390 {
1391         int i;
1392         unsigned long start, backwards, forwards;
1393
1394         if (fragsize > size)
1395                 return -1;
1396
1397         start = 0;
1398         if (line > 1) {
1399                 unsigned long offset = 0;
1400                 i = line-1;
1401                 while (offset + fragsize <= size) {
1402                         if (buf[offset++] == '\n') {
1403                                 start = offset;
1404                                 if (!--i)
1405                                         break;
1406                         }
1407                 }
1408         }
1409
1410         /* Exact line number? */
1411         if (!memcmp(buf + start, fragment, fragsize))
1412                 return start;
1413
1414         /*
1415          * There's probably some smart way to do this, but I'll leave
1416          * that to the smart and beautiful people. I'm simple and stupid.
1417          */
1418         backwards = start;
1419         forwards = start;
1420         for (i = 0; ; i++) {
1421                 unsigned long try;
1422                 int n;
1423
1424                 /* "backward" */
1425                 if (i & 1) {
1426                         if (!backwards) {
1427                                 if (forwards + fragsize > size)
1428                                         break;
1429                                 continue;
1430                         }
1431                         do {
1432                                 --backwards;
1433                         } while (backwards && buf[backwards-1] != '\n');
1434                         try = backwards;
1435                 } else {
1436                         while (forwards + fragsize <= size) {
1437                                 if (buf[forwards++] == '\n')
1438                                         break;
1439                         }
1440                         try = forwards;
1441                 }
1442
1443                 if (try + fragsize > size)
1444                         continue;
1445                 if (memcmp(buf + try, fragment, fragsize))
1446                         continue;
1447                 n = (i >> 1)+1;
1448                 if (i & 1)
1449                         n = -n;
1450                 *lines = n;
1451                 return try;
1452         }
1453
1454         /*
1455          * We should start searching forward and backward.
1456          */
1457         return -1;
1458 }
1459
1460 static void remove_first_line(const char **rbuf, int *rsize)
1461 {
1462         const char *buf = *rbuf;
1463         int size = *rsize;
1464         unsigned long offset;
1465         offset = 0;
1466         while (offset <= size) {
1467                 if (buf[offset++] == '\n')
1468                         break;
1469         }
1470         *rsize = size - offset;
1471         *rbuf = buf + offset;
1472 }
1473
1474 static void remove_last_line(const char **rbuf, int *rsize)
1475 {
1476         const char *buf = *rbuf;
1477         int size = *rsize;
1478         unsigned long offset;
1479         offset = size - 1;
1480         while (offset > 0) {
1481                 if (buf[--offset] == '\n')
1482                         break;
1483         }
1484         *rsize = offset + 1;
1485 }
1486
1487 struct buffer_desc {
1488         char *buffer;
1489         unsigned long size;
1490         unsigned long alloc;
1491 };
1492
1493 static int apply_line(char *output, const char *patch, int plen)
1494 {
1495         /* plen is number of bytes to be copied from patch,
1496          * starting at patch+1 (patch[0] is '+').  Typically
1497          * patch[plen] is '\n'.
1498          */
1499         int add_nl_to_tail = 0;
1500         if ((new_whitespace == strip_whitespace) &&
1501             1 < plen && isspace(patch[plen-1])) {
1502                 if (patch[plen] == '\n')
1503                         add_nl_to_tail = 1;
1504                 plen--;
1505                 while (0 < plen && isspace(patch[plen]))
1506                         plen--;
1507                 applied_after_stripping++;
1508         }
1509         memcpy(output, patch + 1, plen);
1510         if (add_nl_to_tail)
1511                 output[plen++] = '\n';
1512         return plen;
1513 }
1514
1515 static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag, int inaccurate_eof)
1516 {
1517         int match_beginning, match_end;
1518         char *buf = desc->buffer;
1519         const char *patch = frag->patch;
1520         int offset, size = frag->size;
1521         char *old = xmalloc(size);
1522         char *new = xmalloc(size);
1523         const char *oldlines, *newlines;
1524         int oldsize = 0, newsize = 0;
1525         unsigned long leading, trailing;
1526         int pos, lines;
1527
1528         while (size > 0) {
1529                 char first;
1530                 int len = linelen(patch, size);
1531                 int plen;
1532
1533                 if (!len)
1534                         break;
1535
1536                 /*
1537                  * "plen" is how much of the line we should use for
1538                  * the actual patch data. Normally we just remove the
1539                  * first character on the line, but if the line is
1540                  * followed by "\ No newline", then we also remove the
1541                  * last one (which is the newline, of course).
1542                  */
1543                 plen = len-1;
1544                 if (len < size && patch[len] == '\\')
1545                         plen--;
1546                 first = *patch;
1547                 if (apply_in_reverse) {
1548                         if (first == '-')
1549                                 first = '+';
1550                         else if (first == '+')
1551                                 first = '-';
1552                 }
1553                 switch (first) {
1554                 case ' ':
1555                 case '-':
1556                         memcpy(old + oldsize, patch + 1, plen);
1557                         oldsize += plen;
1558                         if (first == '-')
1559                                 break;
1560                 /* Fall-through for ' ' */
1561                 case '+':
1562                         if (first != '+' || !no_add)
1563                                 newsize += apply_line(new + newsize, patch,
1564                                                       plen);
1565                         break;
1566                 case '@': case '\\':
1567                         /* Ignore it, we already handled it */
1568                         break;
1569                 default:
1570                         return -1;
1571                 }
1572                 patch += len;
1573                 size -= len;
1574         }
1575
1576         if (inaccurate_eof && oldsize > 0 && old[oldsize - 1] == '\n' &&
1577                         newsize > 0 && new[newsize - 1] == '\n') {
1578                 oldsize--;
1579                 newsize--;
1580         }
1581
1582         oldlines = old;
1583         newlines = new;
1584         leading = frag->leading;
1585         trailing = frag->trailing;
1586
1587         /*
1588          * If we don't have any leading/trailing data in the patch,
1589          * we want it to match at the beginning/end of the file.
1590          *
1591          * But that would break if the patch is generated with
1592          * --unified=0; sane people wouldn't do that to cause us
1593          * trouble, but we try to please not so sane ones as well.
1594          */
1595         if (unidiff_zero) {
1596                 match_beginning = (!leading && !frag->oldpos);
1597                 match_end = 0;
1598         }
1599         else {
1600                 match_beginning = !leading && (frag->oldpos == 1);
1601                 match_end = !trailing;
1602         }
1603
1604         lines = 0;
1605         pos = frag->newpos;
1606         for (;;) {
1607                 offset = find_offset(buf, desc->size,
1608                                      oldlines, oldsize, pos, &lines);
1609                 if (match_end && offset + oldsize != desc->size)
1610                         offset = -1;
1611                 if (match_beginning && offset)
1612                         offset = -1;
1613                 if (offset >= 0) {
1614                         int diff = newsize - oldsize;
1615                         unsigned long size = desc->size + diff;
1616                         unsigned long alloc = desc->alloc;
1617
1618                         /* Warn if it was necessary to reduce the number
1619                          * of context lines.
1620                          */
1621                         if ((leading != frag->leading) ||
1622                             (trailing != frag->trailing))
1623                                 fprintf(stderr, "Context reduced to (%ld/%ld)"
1624                                         " to apply fragment at %d\n",
1625                                         leading, trailing, pos + lines);
1626
1627                         if (size > alloc) {
1628                                 alloc = size + 8192;
1629                                 desc->alloc = alloc;
1630                                 buf = xrealloc(buf, alloc);
1631                                 desc->buffer = buf;
1632                         }
1633                         desc->size = size;
1634                         memmove(buf + offset + newsize,
1635                                 buf + offset + oldsize,
1636                                 size - offset - newsize);
1637                         memcpy(buf + offset, newlines, newsize);
1638                         offset = 0;
1639
1640                         break;
1641                 }
1642
1643                 /* Am I at my context limits? */
1644                 if ((leading <= p_context) && (trailing <= p_context))
1645                         break;
1646                 if (match_beginning || match_end) {
1647                         match_beginning = match_end = 0;
1648                         continue;
1649                 }
1650                 /* Reduce the number of context lines
1651                  * Reduce both leading and trailing if they are equal
1652                  * otherwise just reduce the larger context.
1653                  */
1654                 if (leading >= trailing) {
1655                         remove_first_line(&oldlines, &oldsize);
1656                         remove_first_line(&newlines, &newsize);
1657                         pos--;
1658                         leading--;
1659                 }
1660                 if (trailing > leading) {
1661                         remove_last_line(&oldlines, &oldsize);
1662                         remove_last_line(&newlines, &newsize);
1663                         trailing--;
1664                 }
1665         }
1666
1667         free(old);
1668         free(new);
1669         return offset;
1670 }
1671
1672 static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch)
1673 {
1674         unsigned long dst_size;
1675         struct fragment *fragment = patch->fragments;
1676         void *data;
1677         void *result;
1678
1679         /* Binary patch is irreversible without the optional second hunk */
1680         if (apply_in_reverse) {
1681                 if (!fragment->next)
1682                         return error("cannot reverse-apply a binary patch "
1683                                      "without the reverse hunk to '%s'",
1684                                      patch->new_name
1685                                      ? patch->new_name : patch->old_name);
1686                 fragment = fragment->next;
1687         }
1688         data = (void*) fragment->patch;
1689         switch (fragment->binary_patch_method) {
1690         case BINARY_DELTA_DEFLATED:
1691                 result = patch_delta(desc->buffer, desc->size,
1692                                      data,
1693                                      fragment->size,
1694                                      &dst_size);
1695                 free(desc->buffer);
1696                 desc->buffer = result;
1697                 break;
1698         case BINARY_LITERAL_DEFLATED:
1699                 free(desc->buffer);
1700                 desc->buffer = data;
1701                 dst_size = fragment->size;
1702                 break;
1703         }
1704         if (!desc->buffer)
1705                 return -1;
1706         desc->size = desc->alloc = dst_size;
1707         return 0;
1708 }
1709
1710 static int apply_binary(struct buffer_desc *desc, struct patch *patch)
1711 {
1712         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1713         unsigned char sha1[20];
1714         unsigned char hdr[50];
1715         int hdrlen;
1716
1717         /* For safety, we require patch index line to contain
1718          * full 40-byte textual SHA1 for old and new, at least for now.
1719          */
1720         if (strlen(patch->old_sha1_prefix) != 40 ||
1721             strlen(patch->new_sha1_prefix) != 40 ||
1722             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1723             get_sha1_hex(patch->new_sha1_prefix, sha1))
1724                 return error("cannot apply binary patch to '%s' "
1725                              "without full index line", name);
1726
1727         if (patch->old_name) {
1728                 /* See if the old one matches what the patch
1729                  * applies to.
1730                  */
1731                 write_sha1_file_prepare(desc->buffer, desc->size,
1732                                         blob_type, sha1, hdr, &hdrlen);
1733                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1734                         return error("the patch applies to '%s' (%s), "
1735                                      "which does not match the "
1736                                      "current contents.",
1737                                      name, sha1_to_hex(sha1));
1738         }
1739         else {
1740                 /* Otherwise, the old one must be empty. */
1741                 if (desc->size)
1742                         return error("the patch applies to an empty "
1743                                      "'%s' but it is not empty", name);
1744         }
1745
1746         get_sha1_hex(patch->new_sha1_prefix, sha1);
1747         if (is_null_sha1(sha1)) {
1748                 free(desc->buffer);
1749                 desc->alloc = desc->size = 0;
1750                 desc->buffer = NULL;
1751                 return 0; /* deletion patch */
1752         }
1753
1754         if (has_sha1_file(sha1)) {
1755                 /* We already have the postimage */
1756                 char type[10];
1757                 unsigned long size;
1758
1759                 free(desc->buffer);
1760                 desc->buffer = read_sha1_file(sha1, type, &size);
1761                 if (!desc->buffer)
1762                         return error("the necessary postimage %s for "
1763                                      "'%s' cannot be read",
1764                                      patch->new_sha1_prefix, name);
1765                 desc->alloc = desc->size = size;
1766         }
1767         else {
1768                 /* We have verified desc matches the preimage;
1769                  * apply the patch data to it, which is stored
1770                  * in the patch->fragments->{patch,size}.
1771                  */
1772                 if (apply_binary_fragment(desc, patch))
1773                         return error("binary patch does not apply to '%s'",
1774                                      name);
1775
1776                 /* verify that the result matches */
1777                 write_sha1_file_prepare(desc->buffer, desc->size, blob_type,
1778                                         sha1, hdr, &hdrlen);
1779                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
1780                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)", name, patch->new_sha1_prefix, sha1_to_hex(sha1));
1781         }
1782
1783         return 0;
1784 }
1785
1786 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1787 {
1788         struct fragment *frag = patch->fragments;
1789         const char *name = patch->old_name ? patch->old_name : patch->new_name;
1790
1791         if (patch->is_binary)
1792                 return apply_binary(desc, patch);
1793
1794         while (frag) {
1795                 if (apply_one_fragment(desc, frag, patch->inaccurate_eof)) {
1796                         error("patch failed: %s:%ld", name, frag->oldpos);
1797                         if (!apply_with_reject)
1798                                 return -1;
1799                         frag->rejected = 1;
1800                 }
1801                 frag = frag->next;
1802         }
1803         return 0;
1804 }
1805
1806 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
1807 {
1808         char *buf;
1809         unsigned long size, alloc;
1810         struct buffer_desc desc;
1811
1812         size = 0;
1813         alloc = 0;
1814         buf = NULL;
1815         if (cached) {
1816                 if (ce) {
1817                         char type[20];
1818                         buf = read_sha1_file(ce->sha1, type, &size);
1819                         if (!buf)
1820                                 return error("read of %s failed",
1821                                              patch->old_name);
1822                         alloc = size;
1823                 }
1824         }
1825         else if (patch->old_name) {
1826                 size = st->st_size;
1827                 alloc = size + 8192;
1828                 buf = xmalloc(alloc);
1829                 if (read_old_data(st, patch->old_name, buf, alloc) != size)
1830                         return error("read of %s failed", patch->old_name);
1831         }
1832
1833         desc.size = size;
1834         desc.alloc = alloc;
1835         desc.buffer = buf;
1836
1837         if (apply_fragments(&desc, patch) < 0)
1838                 return -1; /* note with --reject this succeeds. */
1839
1840         /* NUL terminate the result */
1841         if (desc.alloc <= desc.size)
1842                 desc.buffer = xrealloc(desc.buffer, desc.size + 1);
1843         desc.buffer[desc.size] = 0;
1844
1845         patch->result = desc.buffer;
1846         patch->resultsize = desc.size;
1847
1848         if (0 < patch->is_delete && patch->resultsize)
1849                 return error("removal patch leaves file contents");
1850
1851         return 0;
1852 }
1853
1854 static int check_patch(struct patch *patch, struct patch *prev_patch)
1855 {
1856         struct stat st;
1857         const char *old_name = patch->old_name;
1858         const char *new_name = patch->new_name;
1859         const char *name = old_name ? old_name : new_name;
1860         struct cache_entry *ce = NULL;
1861         int ok_if_exists;
1862
1863         patch->rejected = 1; /* we will drop this after we succeed */
1864         if (old_name) {
1865                 int changed = 0;
1866                 int stat_ret = 0;
1867                 unsigned st_mode = 0;
1868
1869                 if (!cached)
1870                         stat_ret = lstat(old_name, &st);
1871                 if (check_index) {
1872                         int pos = cache_name_pos(old_name, strlen(old_name));
1873                         if (pos < 0)
1874                                 return error("%s: does not exist in index",
1875                                              old_name);
1876                         ce = active_cache[pos];
1877                         if (stat_ret < 0) {
1878                                 struct checkout costate;
1879                                 if (errno != ENOENT)
1880                                         return error("%s: %s", old_name,
1881                                                      strerror(errno));
1882                                 /* checkout */
1883                                 costate.base_dir = "";
1884                                 costate.base_dir_len = 0;
1885                                 costate.force = 0;
1886                                 costate.quiet = 0;
1887                                 costate.not_new = 0;
1888                                 costate.refresh_cache = 1;
1889                                 if (checkout_entry(ce,
1890                                                    &costate,
1891                                                    NULL) ||
1892                                     lstat(old_name, &st))
1893                                         return -1;
1894                         }
1895                         if (!cached)
1896                                 changed = ce_match_stat(ce, &st, 1);
1897                         if (changed)
1898                                 return error("%s: does not match index",
1899                                              old_name);
1900                         if (cached)
1901                                 st_mode = ntohl(ce->ce_mode);
1902                 }
1903                 else if (stat_ret < 0)
1904                         return error("%s: %s", old_name, strerror(errno));
1905
1906                 if (!cached)
1907                         st_mode = ntohl(create_ce_mode(st.st_mode));
1908
1909                 if (patch->is_new < 0)
1910                         patch->is_new = 0;
1911                 if (!patch->old_mode)
1912                         patch->old_mode = st_mode;
1913                 if ((st_mode ^ patch->old_mode) & S_IFMT)
1914                         return error("%s: wrong type", old_name);
1915                 if (st_mode != patch->old_mode)
1916                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
1917                                 old_name, st_mode, patch->old_mode);
1918         }
1919
1920         if (new_name && prev_patch && 0 < prev_patch->is_delete &&
1921             !strcmp(prev_patch->old_name, new_name))
1922                 /* A type-change diff is always split into a patch to
1923                  * delete old, immediately followed by a patch to
1924                  * create new (see diff.c::run_diff()); in such a case
1925                  * it is Ok that the entry to be deleted by the
1926                  * previous patch is still in the working tree and in
1927                  * the index.
1928                  */
1929                 ok_if_exists = 1;
1930         else
1931                 ok_if_exists = 0;
1932
1933         if (new_name &&
1934             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
1935                 if (check_index &&
1936                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
1937                     !ok_if_exists)
1938                         return error("%s: already exists in index", new_name);
1939                 if (!cached) {
1940                         struct stat nst;
1941                         if (!lstat(new_name, &nst)) {
1942                                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
1943                                         ; /* ok */
1944                                 else
1945                                         return error("%s: already exists in working directory", new_name);
1946                         }
1947                         else if ((errno != ENOENT) && (errno != ENOTDIR))
1948                                 return error("%s: %s", new_name, strerror(errno));
1949                 }
1950                 if (!patch->new_mode) {
1951                         if (0 < patch->is_new)
1952                                 patch->new_mode = S_IFREG | 0644;
1953                         else
1954                                 patch->new_mode = patch->old_mode;
1955                 }
1956         }
1957
1958         if (new_name && old_name) {
1959                 int same = !strcmp(old_name, new_name);
1960                 if (!patch->new_mode)
1961                         patch->new_mode = patch->old_mode;
1962                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
1963                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
1964                                 patch->new_mode, new_name, patch->old_mode,
1965                                 same ? "" : " of ", same ? "" : old_name);
1966         }
1967
1968         if (apply_data(patch, &st, ce) < 0)
1969                 return error("%s: patch does not apply", name);
1970         patch->rejected = 0;
1971         return 0;
1972 }
1973
1974 static int check_patch_list(struct patch *patch)
1975 {
1976         struct patch *prev_patch = NULL;
1977         int err = 0;
1978
1979         for (prev_patch = NULL; patch ; patch = patch->next) {
1980                 if (apply_verbosely)
1981                         say_patch_name(stderr,
1982                                        "Checking patch ", patch, "...\n");
1983                 err |= check_patch(patch, prev_patch);
1984                 prev_patch = patch;
1985         }
1986         return err;
1987 }
1988
1989 static void show_index_list(struct patch *list)
1990 {
1991         struct patch *patch;
1992
1993         /* Once we start supporting the reverse patch, it may be
1994          * worth showing the new sha1 prefix, but until then...
1995          */
1996         for (patch = list; patch; patch = patch->next) {
1997                 const unsigned char *sha1_ptr;
1998                 unsigned char sha1[20];
1999                 const char *name;
2000
2001                 name = patch->old_name ? patch->old_name : patch->new_name;
2002                 if (0 < patch->is_new)
2003                         sha1_ptr = null_sha1;
2004                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2005                         die("sha1 information is lacking or useless (%s).",
2006                             name);
2007                 else
2008                         sha1_ptr = sha1;
2009
2010                 printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
2011                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
2012                         quote_c_style(name, NULL, stdout, 0);
2013                 else
2014                         fputs(name, stdout);
2015                 putchar(line_termination);
2016         }
2017 }
2018
2019 static void stat_patch_list(struct patch *patch)
2020 {
2021         int files, adds, dels;
2022
2023         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2024                 files++;
2025                 adds += patch->lines_added;
2026                 dels += patch->lines_deleted;
2027                 show_stats(patch);
2028         }
2029
2030         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2031 }
2032
2033 static void numstat_patch_list(struct patch *patch)
2034 {
2035         for ( ; patch; patch = patch->next) {
2036                 const char *name;
2037                 name = patch->new_name ? patch->new_name : patch->old_name;
2038                 printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
2039                 if (line_termination && quote_c_style(name, NULL, NULL, 0))
2040                         quote_c_style(name, NULL, stdout, 0);
2041                 else
2042                         fputs(name, stdout);
2043                 putchar('\n');
2044         }
2045 }
2046
2047 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2048 {
2049         if (mode)
2050                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2051         else
2052                 printf(" %s %s\n", newdelete, name);
2053 }
2054
2055 static void show_mode_change(struct patch *p, int show_name)
2056 {
2057         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2058                 if (show_name)
2059                         printf(" mode change %06o => %06o %s\n",
2060                                p->old_mode, p->new_mode, p->new_name);
2061                 else
2062                         printf(" mode change %06o => %06o\n",
2063                                p->old_mode, p->new_mode);
2064         }
2065 }
2066
2067 static void show_rename_copy(struct patch *p)
2068 {
2069         const char *renamecopy = p->is_rename ? "rename" : "copy";
2070         const char *old, *new;
2071
2072         /* Find common prefix */
2073         old = p->old_name;
2074         new = p->new_name;
2075         while (1) {
2076                 const char *slash_old, *slash_new;
2077                 slash_old = strchr(old, '/');
2078                 slash_new = strchr(new, '/');
2079                 if (!slash_old ||
2080                     !slash_new ||
2081                     slash_old - old != slash_new - new ||
2082                     memcmp(old, new, slash_new - new))
2083                         break;
2084                 old = slash_old + 1;
2085                 new = slash_new + 1;
2086         }
2087         /* p->old_name thru old is the common prefix, and old and new
2088          * through the end of names are renames
2089          */
2090         if (old != p->old_name)
2091                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2092                        (int)(old - p->old_name), p->old_name,
2093                        old, new, p->score);
2094         else
2095                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2096                        p->old_name, p->new_name, p->score);
2097         show_mode_change(p, 0);
2098 }
2099
2100 static void summary_patch_list(struct patch *patch)
2101 {
2102         struct patch *p;
2103
2104         for (p = patch; p; p = p->next) {
2105                 if (p->is_new)
2106                         show_file_mode_name("create", p->new_mode, p->new_name);
2107                 else if (p->is_delete)
2108                         show_file_mode_name("delete", p->old_mode, p->old_name);
2109                 else {
2110                         if (p->is_rename || p->is_copy)
2111                                 show_rename_copy(p);
2112                         else {
2113                                 if (p->score) {
2114                                         printf(" rewrite %s (%d%%)\n",
2115                                                p->new_name, p->score);
2116                                         show_mode_change(p, 0);
2117                                 }
2118                                 else
2119                                         show_mode_change(p, 1);
2120                         }
2121                 }
2122         }
2123 }
2124
2125 static void patch_stats(struct patch *patch)
2126 {
2127         int lines = patch->lines_added + patch->lines_deleted;
2128
2129         if (lines > max_change)
2130                 max_change = lines;
2131         if (patch->old_name) {
2132                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2133                 if (!len)
2134                         len = strlen(patch->old_name);
2135                 if (len > max_len)
2136                         max_len = len;
2137         }
2138         if (patch->new_name) {
2139                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2140                 if (!len)
2141                         len = strlen(patch->new_name);
2142                 if (len > max_len)
2143                         max_len = len;
2144         }
2145 }
2146
2147 static void remove_file(struct patch *patch)
2148 {
2149         if (write_index) {
2150                 if (remove_file_from_cache(patch->old_name) < 0)
2151                         die("unable to remove %s from index", patch->old_name);
2152                 cache_tree_invalidate_path(active_cache_tree, patch->old_name);
2153         }
2154         if (!cached)
2155                 unlink(patch->old_name);
2156 }
2157
2158 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2159 {
2160         struct stat st;
2161         struct cache_entry *ce;
2162         int namelen = strlen(path);
2163         unsigned ce_size = cache_entry_size(namelen);
2164
2165         if (!write_index)
2166                 return;
2167
2168         ce = xcalloc(1, ce_size);
2169         memcpy(ce->name, path, namelen);
2170         ce->ce_mode = create_ce_mode(mode);
2171         ce->ce_flags = htons(namelen);
2172         if (!cached) {
2173                 if (lstat(path, &st) < 0)
2174                         die("unable to stat newly created file %s", path);
2175                 fill_stat_cache_info(ce, &st);
2176         }
2177         if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2178                 die("unable to create backing store for newly created file %s", path);
2179         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2180                 die("unable to add cache entry for %s", path);
2181 }
2182
2183 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2184 {
2185         int fd;
2186
2187         if (S_ISLNK(mode))
2188                 /* Although buf:size is counted string, it also is NUL
2189                  * terminated.
2190                  */
2191                 return symlink(buf, path);
2192         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2193         if (fd < 0)
2194                 return -1;
2195         while (size) {
2196                 int written = xwrite(fd, buf, size);
2197                 if (written < 0)
2198                         die("writing file %s: %s", path, strerror(errno));
2199                 if (!written)
2200                         die("out of space writing file %s", path);
2201                 buf += written;
2202                 size -= written;
2203         }
2204         if (close(fd) < 0)
2205                 die("closing file %s: %s", path, strerror(errno));
2206         return 0;
2207 }
2208
2209 /*
2210  * We optimistically assume that the directories exist,
2211  * which is true 99% of the time anyway. If they don't,
2212  * we create them and try again.
2213  */
2214 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2215 {
2216         if (cached)
2217                 return;
2218         if (!try_create_file(path, mode, buf, size))
2219                 return;
2220
2221         if (errno == ENOENT) {
2222                 if (safe_create_leading_directories(path))
2223                         return;
2224                 if (!try_create_file(path, mode, buf, size))
2225                         return;
2226         }
2227
2228         if (errno == EEXIST || errno == EACCES) {
2229                 /* We may be trying to create a file where a directory
2230                  * used to be.
2231                  */
2232                 struct stat st;
2233                 errno = 0;
2234                 if (!lstat(path, &st) && S_ISDIR(st.st_mode) && !rmdir(path))
2235                         errno = EEXIST;
2236         }
2237
2238         if (errno == EEXIST) {
2239                 unsigned int nr = getpid();
2240
2241                 for (;;) {
2242                         const char *newpath;
2243                         newpath = mkpath("%s~%u", path, nr);
2244                         if (!try_create_file(newpath, mode, buf, size)) {
2245                                 if (!rename(newpath, path))
2246                                         return;
2247                                 unlink(newpath);
2248                                 break;
2249                         }
2250                         if (errno != EEXIST)
2251                                 break;
2252                         ++nr;
2253                 }
2254         }
2255         die("unable to write file %s mode %o", path, mode);
2256 }
2257
2258 static void create_file(struct patch *patch)
2259 {
2260         char *path = patch->new_name;
2261         unsigned mode = patch->new_mode;
2262         unsigned long size = patch->resultsize;
2263         char *buf = patch->result;
2264
2265         if (!mode)
2266                 mode = S_IFREG | 0644;
2267         create_one_file(path, mode, buf, size);
2268         add_index_file(path, mode, buf, size);
2269         cache_tree_invalidate_path(active_cache_tree, path);
2270 }
2271
2272 /* phase zero is to remove, phase one is to create */
2273 static void write_out_one_result(struct patch *patch, int phase)
2274 {
2275         if (patch->is_delete > 0) {
2276                 if (phase == 0)
2277                         remove_file(patch);
2278                 return;
2279         }
2280         if (patch->is_new > 0 || patch->is_copy) {
2281                 if (phase == 1)
2282                         create_file(patch);
2283                 return;
2284         }
2285         /*
2286          * Rename or modification boils down to the same
2287          * thing: remove the old, write the new
2288          */
2289         if (phase == 0)
2290                 remove_file(patch);
2291         if (phase == 1)
2292                 create_file(patch);
2293 }
2294
2295 static int write_out_one_reject(struct patch *patch)
2296 {
2297         FILE *rej;
2298         char namebuf[PATH_MAX];
2299         struct fragment *frag;
2300         int cnt = 0;
2301
2302         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2303                 if (!frag->rejected)
2304                         continue;
2305                 cnt++;
2306         }
2307
2308         if (!cnt) {
2309                 if (apply_verbosely)
2310                         say_patch_name(stderr,
2311                                        "Applied patch ", patch, " cleanly.\n");
2312                 return 0;
2313         }
2314
2315         /* This should not happen, because a removal patch that leaves
2316          * contents are marked "rejected" at the patch level.
2317          */
2318         if (!patch->new_name)
2319                 die("internal error");
2320
2321         /* Say this even without --verbose */
2322         say_patch_name(stderr, "Applying patch ", patch, " with");
2323         fprintf(stderr, " %d rejects...\n", cnt);
2324
2325         cnt = strlen(patch->new_name);
2326         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2327                 cnt = ARRAY_SIZE(namebuf) - 5;
2328                 fprintf(stderr,
2329                         "warning: truncating .rej filename to %.*s.rej",
2330                         cnt - 1, patch->new_name);
2331         }
2332         memcpy(namebuf, patch->new_name, cnt);
2333         memcpy(namebuf + cnt, ".rej", 5);
2334
2335         rej = fopen(namebuf, "w");
2336         if (!rej)
2337                 return error("cannot open %s: %s", namebuf, strerror(errno));
2338
2339         /* Normal git tools never deal with .rej, so do not pretend
2340          * this is a git patch by saying --git nor give extended
2341          * headers.  While at it, maybe please "kompare" that wants
2342          * the trailing TAB and some garbage at the end of line ;-).
2343          */
2344         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2345                 patch->new_name, patch->new_name);
2346         for (cnt = 1, frag = patch->fragments;
2347              frag;
2348              cnt++, frag = frag->next) {
2349                 if (!frag->rejected) {
2350                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2351                         continue;
2352                 }
2353                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2354                 fprintf(rej, "%.*s", frag->size, frag->patch);
2355                 if (frag->patch[frag->size-1] != '\n')
2356                         fputc('\n', rej);
2357         }
2358         fclose(rej);
2359         return -1;
2360 }
2361
2362 static int write_out_results(struct patch *list, int skipped_patch)
2363 {
2364         int phase;
2365         int errs = 0;
2366         struct patch *l;
2367
2368         if (!list && !skipped_patch)
2369                 return error("No changes");
2370
2371         for (phase = 0; phase < 2; phase++) {
2372                 l = list;
2373                 while (l) {
2374                         if (l->rejected)
2375                                 errs = 1;
2376                         else {
2377                                 write_out_one_result(l, phase);
2378                                 if (phase == 1 && write_out_one_reject(l))
2379                                         errs = 1;
2380                         }
2381                         l = l->next;
2382                 }
2383         }
2384         return errs;
2385 }
2386
2387 static struct lock_file lock_file;
2388
2389 static struct excludes {
2390         struct excludes *next;
2391         const char *path;
2392 } *excludes;
2393
2394 static int use_patch(struct patch *p)
2395 {
2396         const char *pathname = p->new_name ? p->new_name : p->old_name;
2397         struct excludes *x = excludes;
2398         while (x) {
2399                 if (fnmatch(x->path, pathname, 0) == 0)
2400                         return 0;
2401                 x = x->next;
2402         }
2403         if (0 < prefix_length) {
2404                 int pathlen = strlen(pathname);
2405                 if (pathlen <= prefix_length ||
2406                     memcmp(prefix, pathname, prefix_length))
2407                         return 0;
2408         }
2409         return 1;
2410 }
2411
2412 static int apply_patch(int fd, const char *filename, int inaccurate_eof)
2413 {
2414         unsigned long offset, size;
2415         char *buffer = read_patch_file(fd, &size);
2416         struct patch *list = NULL, **listp = &list;
2417         int skipped_patch = 0;
2418
2419         patch_input_file = filename;
2420         if (!buffer)
2421                 return -1;
2422         offset = 0;
2423         while (size > 0) {
2424                 struct patch *patch;
2425                 int nr;
2426
2427                 patch = xcalloc(1, sizeof(*patch));
2428                 patch->inaccurate_eof = inaccurate_eof;
2429                 nr = parse_chunk(buffer + offset, size, patch);
2430                 if (nr < 0)
2431                         break;
2432                 if (apply_in_reverse)
2433                         reverse_patches(patch);
2434                 if (use_patch(patch)) {
2435                         patch_stats(patch);
2436                         *listp = patch;
2437                         listp = &patch->next;
2438                 } else {
2439                         /* perhaps free it a bit better? */
2440                         free(patch);
2441                         skipped_patch++;
2442                 }
2443                 offset += nr;
2444                 size -= nr;
2445         }
2446
2447         if (whitespace_error && (new_whitespace == error_on_whitespace))
2448                 apply = 0;
2449
2450         write_index = check_index && apply;
2451         if (write_index && newfd < 0)
2452                 newfd = hold_lock_file_for_update(&lock_file,
2453                                                   get_index_file(), 1);
2454         if (check_index) {
2455                 if (read_cache() < 0)
2456                         die("unable to read index file");
2457         }
2458
2459         if ((check || apply) &&
2460             check_patch_list(list) < 0 &&
2461             !apply_with_reject)
2462                 exit(1);
2463
2464         if (apply && write_out_results(list, skipped_patch))
2465                 exit(1);
2466
2467         if (show_index_info)
2468                 show_index_list(list);
2469
2470         if (diffstat)
2471                 stat_patch_list(list);
2472
2473         if (numstat)
2474                 numstat_patch_list(list);
2475
2476         if (summary)
2477                 summary_patch_list(list);
2478
2479         free(buffer);
2480         return 0;
2481 }
2482
2483 static int git_apply_config(const char *var, const char *value)
2484 {
2485         if (!strcmp(var, "apply.whitespace")) {
2486                 apply_default_whitespace = xstrdup(value);
2487                 return 0;
2488         }
2489         return git_default_config(var, value);
2490 }
2491
2492
2493 int cmd_apply(int argc, const char **argv, const char *prefix)
2494 {
2495         int i;
2496         int read_stdin = 1;
2497         int inaccurate_eof = 0;
2498         int errs = 0;
2499
2500         const char *whitespace_option = NULL;
2501
2502         for (i = 1; i < argc; i++) {
2503                 const char *arg = argv[i];
2504                 char *end;
2505                 int fd;
2506
2507                 if (!strcmp(arg, "-")) {
2508                         errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2509                         read_stdin = 0;
2510                         continue;
2511                 }
2512                 if (!strncmp(arg, "--exclude=", 10)) {
2513                         struct excludes *x = xmalloc(sizeof(*x));
2514                         x->path = arg + 10;
2515                         x->next = excludes;
2516                         excludes = x;
2517                         continue;
2518                 }
2519                 if (!strncmp(arg, "-p", 2)) {
2520                         p_value = atoi(arg + 2);
2521                         continue;
2522                 }
2523                 if (!strcmp(arg, "--no-add")) {
2524                         no_add = 1;
2525                         continue;
2526                 }
2527                 if (!strcmp(arg, "--stat")) {
2528                         apply = 0;
2529                         diffstat = 1;
2530                         continue;
2531                 }
2532                 if (!strcmp(arg, "--allow-binary-replacement") ||
2533                     !strcmp(arg, "--binary")) {
2534                         continue; /* now no-op */
2535                 }
2536                 if (!strcmp(arg, "--numstat")) {
2537                         apply = 0;
2538                         numstat = 1;
2539                         continue;
2540                 }
2541                 if (!strcmp(arg, "--summary")) {
2542                         apply = 0;
2543                         summary = 1;
2544                         continue;
2545                 }
2546                 if (!strcmp(arg, "--check")) {
2547                         apply = 0;
2548                         check = 1;
2549                         continue;
2550                 }
2551                 if (!strcmp(arg, "--index")) {
2552                         check_index = 1;
2553                         continue;
2554                 }
2555                 if (!strcmp(arg, "--cached")) {
2556                         check_index = 1;
2557                         cached = 1;
2558                         continue;
2559                 }
2560                 if (!strcmp(arg, "--apply")) {
2561                         apply = 1;
2562                         continue;
2563                 }
2564                 if (!strcmp(arg, "--index-info")) {
2565                         apply = 0;
2566                         show_index_info = 1;
2567                         continue;
2568                 }
2569                 if (!strcmp(arg, "-z")) {
2570                         line_termination = 0;
2571                         continue;
2572                 }
2573                 if (!strncmp(arg, "-C", 2)) {
2574                         p_context = strtoul(arg + 2, &end, 0);
2575                         if (*end != '\0')
2576                                 die("unrecognized context count '%s'", arg + 2);
2577                         continue;
2578                 }
2579                 if (!strncmp(arg, "--whitespace=", 13)) {
2580                         whitespace_option = arg + 13;
2581                         parse_whitespace_option(arg + 13);
2582                         continue;
2583                 }
2584                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
2585                         apply_in_reverse = 1;
2586                         continue;
2587                 }
2588                 if (!strcmp(arg, "--unidiff-zero")) {
2589                         unidiff_zero = 1;
2590                         continue;
2591                 }
2592                 if (!strcmp(arg, "--reject")) {
2593                         apply = apply_with_reject = apply_verbosely = 1;
2594                         continue;
2595                 }
2596                 if (!strcmp(arg, "--verbose")) {
2597                         apply_verbosely = 1;
2598                         continue;
2599                 }
2600                 if (!strcmp(arg, "--inaccurate-eof")) {
2601                         inaccurate_eof = 1;
2602                         continue;
2603                 }
2604
2605                 if (check_index && prefix_length < 0) {
2606                         prefix = setup_git_directory();
2607                         prefix_length = prefix ? strlen(prefix) : 0;
2608                         git_config(git_apply_config);
2609                         if (!whitespace_option && apply_default_whitespace)
2610                                 parse_whitespace_option(apply_default_whitespace);
2611                 }
2612                 if (0 < prefix_length)
2613                         arg = prefix_filename(prefix, prefix_length, arg);
2614
2615                 fd = open(arg, O_RDONLY);
2616                 if (fd < 0)
2617                         usage(apply_usage);
2618                 read_stdin = 0;
2619                 set_default_whitespace_mode(whitespace_option);
2620                 errs |= apply_patch(fd, arg, inaccurate_eof);
2621                 close(fd);
2622         }
2623         set_default_whitespace_mode(whitespace_option);
2624         if (read_stdin)
2625                 errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2626         if (whitespace_error) {
2627                 if (squelch_whitespace_errors &&
2628                     squelch_whitespace_errors < whitespace_error) {
2629                         int squelched =
2630                                 whitespace_error - squelch_whitespace_errors;
2631                         fprintf(stderr, "warning: squelched %d "
2632                                 "whitespace error%s\n",
2633                                 squelched,
2634                                 squelched == 1 ? "" : "s");
2635                 }
2636                 if (new_whitespace == error_on_whitespace)
2637                         die("%d line%s add%s trailing whitespaces.",
2638                             whitespace_error,
2639                             whitespace_error == 1 ? "" : "s",
2640                             whitespace_error == 1 ? "s" : "");
2641                 if (applied_after_stripping)
2642                         fprintf(stderr, "warning: %d line%s applied after"
2643                                 " stripping trailing whitespaces.\n",
2644                                 applied_after_stripping,
2645                                 applied_after_stripping == 1 ? "" : "s");
2646                 else if (whitespace_error)
2647                         fprintf(stderr, "warning: %d line%s add%s trailing"
2648                                 " whitespaces.\n",
2649                                 whitespace_error,
2650                                 whitespace_error == 1 ? "" : "s",
2651                                 whitespace_error == 1 ? "s" : "");
2652         }
2653
2654         if (write_index) {
2655                 if (write_cache(newfd, active_cache, active_nr) ||
2656                     close(newfd) || commit_lock_file(&lock_file))
2657                         die("Unable to write new index file");
2658         }
2659
2660         return !!errs;
2661 }