builtin-apply.c

   1 /*
   2  * apply.c
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  *
   6  * This applies patches on top of some (arbitrary) version of the SCM.
   7  *
   8  */
   9 #include "cache.h"
  10 #include "cache-tree.h"
  11 #include "quote.h"
  12 #include "blob.h"
  13 #include "delta.h"
  14 #include "builtin.h"
  15
  16 /*
  17  *  --check turns on checking that the working tree matches the
  18  *    files that are being modified, but doesn't apply the patch
  19  *  --stat does just a diffstat, and doesn't actually apply
  20  *  --numstat does numeric diffstat, and doesn't actually apply
  21  *  --index-info shows the old and new index info for paths if available.
  22  *  --index updates the cache as well.
  23  *  --cached updates only the cache without ever touching the working tree.
  24  */
  25 static const char *prefix;
  26 static int prefix_length = -1;
  27 static int newfd = -1;
  28
  29 static int unidiff_zero;
  30 static int p_value = 1;
  31 static int p_value_known;
  32 static int check_index;
  33 static int update_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 const char *fake_ancestor;
  45 static int line_termination = '\n';
  46 static unsigned long p_context = ULONG_MAX;
  47 static const char apply_usage[] =
  48 "git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [--verbose] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|fix|error|error-all>] <patch>...";
  49
  50 static enum ws_error_action {
  51         nowarn_ws_error,
  52         warn_on_ws_error,
  53         die_on_ws_error,
  54         correct_ws_error,
  55 } ws_error_action = warn_on_ws_error;
  56 static int whitespace_error;
  57 static int squelch_whitespace_errors = 5;
  58 static int applied_after_fixing_ws;
  59 static const char *patch_input_file;
  60
  61 static void parse_whitespace_option(const char *option)
  62 {
  63         if (!option) {
  64                 ws_error_action = warn_on_ws_error;
  65                 return;
  66         }
  67         if (!strcmp(option, "warn")) {
  68                 ws_error_action = warn_on_ws_error;
  69                 return;
  70         }
  71         if (!strcmp(option, "nowarn")) {
  72                 ws_error_action = nowarn_ws_error;
  73                 return;
  74         }
  75         if (!strcmp(option, "error")) {
  76                 ws_error_action = die_on_ws_error;
  77                 return;
  78         }
  79         if (!strcmp(option, "error-all")) {
  80                 ws_error_action = die_on_ws_error;
  81                 squelch_whitespace_errors = 0;
  82                 return;
  83         }
  84         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
  85                 ws_error_action = correct_ws_error;
  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                 ws_error_action = (apply ? warn_on_ws_error : nowarn_ws_error);
  95 }
  96
  97 /*
  98  * For "diff-stat" like behaviour, we keep track of the biggest change
  99  * we've seen, and the longest filename. That allows us to do simple
 100  * scaling.
 101  */
 102 static int max_change, max_len;
 103
 104 /*
 105  * Various "current state", notably line numbers and what
 106  * file (and how) we're patching right now.. The "is_xxxx"
 107  * things are flags, where -1 means "don't know yet".
 108  */
 109 static int linenr = 1;
 110
 111 /*
 112  * This represents one "hunk" from a patch, starting with
 113  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 114  * patch text is pointed at by patch, and its byte length
 115  * is stored in size.  leading and trailing are the number
 116  * of context lines.
 117  */
 118 struct fragment {
 119         unsigned long leading, trailing;
 120         unsigned long oldpos, oldlines;
 121         unsigned long newpos, newlines;
 122         const char *patch;
 123         int size;
 124         int rejected;
 125         struct fragment *next;
 126 };
 127
 128 /*
 129  * When dealing with a binary patch, we reuse "leading" field
 130  * to store the type of the binary hunk, either deflated "delta"
 131  * or deflated "literal".
 132  */
 133 #define binary_patch_method leading
 134 #define BINARY_DELTA_DEFLATED   1
 135 #define BINARY_LITERAL_DEFLATED 2
 136
 137 /*
 138  * This represents a "patch" to a file, both metainfo changes
 139  * such as creation/deletion, filemode and content changes represented
 140  * as a series of fragments.
 141  */
 142 struct patch {
 143         char *new_name, *old_name, *def_name;
 144         unsigned int old_mode, new_mode;
 145         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
 146         int rejected;
 147         unsigned ws_rule;
 148         unsigned long deflate_origlen;
 149         int lines_added, lines_deleted;
 150         int score;
 151         unsigned int is_toplevel_relative:1;
 152         unsigned int inaccurate_eof:1;
 153         unsigned int is_binary:1;
 154         unsigned int is_copy:1;
 155         unsigned int is_rename:1;
 156         struct fragment *fragments;
 157         char *result;
 158         size_t resultsize;
 159         char old_sha1_prefix[41];
 160         char new_sha1_prefix[41];
 161         struct patch *next;
 162 };
 163
 164 /*
 165  * A line in a file, len-bytes long (includes the terminating LF,
 166  * except for an incomplete line at the end if the file ends with
 167  * one), and its contents hashes to 'hash'.
 168  */
 169 struct line {
 170         size_t len;
 171         unsigned hash : 24;
 172         unsigned flag : 8;
 173 #define LINE_COMMON     1
 174 };
 175
 176 /*
 177  * This represents a "file", which is an array of "lines".
 178  */
 179 struct image {
 180         char *buf;
 181         size_t len;
 182         size_t nr;
 183         size_t alloc;
 184         struct line *line_allocated;
 185         struct line *line;
 186 };
 187
 188 static uint32_t hash_line(const char *cp, size_t len)
 189 {
 190         size_t i;
 191         uint32_t h;
 192         for (i = 0, h = 0; i < len; i++) {
 193                 if (!isspace(cp[i])) {
 194                         h = h * 3 + (cp[i] & 0xff);
 195                 }
 196         }
 197         return h;
 198 }
 199
 200 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
 201 {
 202         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
 203         img->line_allocated[img->nr].len = len;
 204         img->line_allocated[img->nr].hash = hash_line(bol, len);
 205         img->line_allocated[img->nr].flag = flag;
 206         img->nr++;
 207 }
 208
 209 static void prepare_image(struct image *image, char *buf, size_t len,
 210                           int prepare_linetable)
 211 {
 212         const char *cp, *ep;
 213
 214         memset(image, 0, sizeof(*image));
 215         image->buf = buf;
 216         image->len = len;
 217
 218         if (!prepare_linetable)
 219                 return;
 220
 221         ep = image->buf + image->len;
 222         cp = image->buf;
 223         while (cp < ep) {
 224                 const char *next;
 225                 for (next = cp; next < ep && *next != '\n'; next++)
 226                         ;
 227                 if (next < ep)
 228                         next++;
 229                 add_line_info(image, cp, next - cp, 0);
 230                 cp = next;
 231         }
 232         image->line = image->line_allocated;
 233 }
 234
 235 static void clear_image(struct image *image)
 236 {
 237         free(image->buf);
 238         image->buf = NULL;
 239         image->len = 0;
 240 }
 241
 242 static void say_patch_name(FILE *output, const char *pre,
 243                            struct patch *patch, const char *post)
 244 {
 245         fputs(pre, output);
 246         if (patch->old_name && patch->new_name &&
 247             strcmp(patch->old_name, patch->new_name)) {
 248                 quote_c_style(patch->old_name, NULL, output, 0);
 249                 fputs(" => ", output);
 250                 quote_c_style(patch->new_name, NULL, output, 0);
 251         } else {
 252                 const char *n = patch->new_name;
 253                 if (!n)
 254                         n = patch->old_name;
 255                 quote_c_style(n, NULL, output, 0);
 256         }
 257         fputs(post, output);
 258 }
 259
 260 #define CHUNKSIZE (8192)
 261 #define SLOP (16)
 262
 263 static void read_patch_file(struct strbuf *sb, int fd)
 264 {
 265         if (strbuf_read(sb, fd, 0) < 0)
 266                 die("git-apply: read returned %s", strerror(errno));
 267
 268         /*
 269          * Make sure that we have some slop in the buffer
 270          * so that we can do speculative "memcmp" etc, and
 271          * see to it that it is NUL-filled.
 272          */
 273         strbuf_grow(sb, SLOP);
 274         memset(sb->buf + sb->len, 0, SLOP);
 275 }
 276
 277 static unsigned long linelen(const char *buffer, unsigned long size)
 278 {
 279         unsigned long len = 0;
 280         while (size--) {
 281                 len++;
 282                 if (*buffer++ == '\n')
 283                         break;
 284         }
 285         return len;
 286 }
 287
 288 static int is_dev_null(const char *str)
 289 {
 290         return !memcmp("/dev/null", str, 9) && isspace(str[9]);
 291 }
 292
 293 #define TERM_SPACE      1
 294 #define TERM_TAB        2
 295
 296 static int name_terminate(const char *name, int namelen, int c, int terminate)
 297 {
 298         if (c == ' ' && !(terminate & TERM_SPACE))
 299                 return 0;
 300         if (c == '\t' && !(terminate & TERM_TAB))
 301                 return 0;
 302
 303         return 1;
 304 }
 305
 306 static char *find_name(const char *line, char *def, int p_value, int terminate)
 307 {
 308         int len;
 309         const char *start = line;
 310
 311         if (*line == '"') {
 312                 struct strbuf name;
 313
 314                 /*
 315                  * Proposed "new-style" GNU patch/diff format; see
 316                  * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
 317                  */
 318                 strbuf_init(&name, 0);
 319                 if (!unquote_c_style(&name, line, NULL)) {
 320                         char *cp;
 321
 322                         for (cp = name.buf; p_value; p_value--) {
 323                                 cp = strchr(cp, '/');
 324                                 if (!cp)
 325                                         break;
 326                                 cp++;
 327                         }
 328                         if (cp) {
 329                                 /* name can later be freed, so we need
 330                                  * to memmove, not just return cp
 331                                  */
 332                                 strbuf_remove(&name, 0, cp - name.buf);
 333                                 free(def);
 334                                 return strbuf_detach(&name, NULL);
 335                         }
 336                 }
 337                 strbuf_release(&name);
 338         }
 339
 340         for (;;) {
 341                 char c = *line;
 342
 343                 if (isspace(c)) {
 344                         if (c == '\n')
 345                                 break;
 346                         if (name_terminate(start, line-start, c, terminate))
 347                                 break;
 348                 }
 349                 line++;
 350                 if (c == '/' && !--p_value)
 351                         start = line;
 352         }
 353         if (!start)
 354                 return def;
 355         len = line - start;
 356         if (!len)
 357                 return def;
 358
 359         /*
 360          * Generally we prefer the shorter name, especially
 361          * if the other one is just a variation of that with
 362          * something else tacked on to the end (ie "file.orig"
 363          * or "file~").
 364          */
 365         if (def) {
 366                 int deflen = strlen(def);
 367                 if (deflen < len && !strncmp(start, def, deflen))
 368                         return def;
 369                 free(def);
 370         }
 371
 372         return xmemdupz(start, len);
 373 }
 374
 375 static int count_slashes(const char *cp)
 376 {
 377         int cnt = 0;
 378         char ch;
 379
 380         while ((ch = *cp++))
 381                 if (ch == '/')
 382                         cnt++;
 383         return cnt;
 384 }
 385
 386 /*
 387  * Given the string after "--- " or "+++ ", guess the appropriate
 388  * p_value for the given patch.
 389  */
 390 static int guess_p_value(const char *nameline)
 391 {
 392         char *name, *cp;
 393         int val = -1;
 394
 395         if (is_dev_null(nameline))
 396                 return -1;
 397         name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
 398         if (!name)
 399                 return -1;
 400         cp = strchr(name, '/');
 401         if (!cp)
 402                 val = 0;
 403         else if (prefix) {
 404                 /*
 405                  * Does it begin with "a/$our-prefix" and such?  Then this is
 406                  * very likely to apply to our directory.
 407                  */
 408                 if (!strncmp(name, prefix, prefix_length))
 409                         val = count_slashes(prefix);
 410                 else {
 411                         cp++;
 412                         if (!strncmp(cp, prefix, prefix_length))
 413                                 val = count_slashes(prefix) + 1;
 414                 }
 415         }
 416         free(name);
 417         return val;
 418 }
 419
 420 /*
 421  * Get the name etc info from the --/+++ lines of a traditional patch header
 422  *
 423  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 424  * files, we can happily check the index for a match, but for creating a
 425  * new file we should try to match whatever "patch" does. I have no idea.
 426  */
 427 static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
 428 {
 429         char *name;
 430
 431         first += 4;     /* skip "--- " */
 432         second += 4;    /* skip "+++ " */
 433         if (!p_value_known) {
 434                 int p, q;
 435                 p = guess_p_value(first);
 436                 q = guess_p_value(second);
 437                 if (p < 0) p = q;
 438                 if (0 <= p && p == q) {
 439                         p_value = p;
 440                         p_value_known = 1;
 441                 }
 442         }
 443         if (is_dev_null(first)) {
 444                 patch->is_new = 1;
 445                 patch->is_delete = 0;
 446                 name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
 447                 patch->new_name = name;
 448         } else if (is_dev_null(second)) {
 449                 patch->is_new = 0;
 450                 patch->is_delete = 1;
 451                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 452                 patch->old_name = name;
 453         } else {
 454                 name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 455                 name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
 456                 patch->old_name = patch->new_name = name;
 457         }
 458         if (!name)
 459                 die("unable to find filename in patch at line %d", linenr);
 460 }
 461
 462 static int gitdiff_hdrend(const char *line, struct patch *patch)
 463 {
 464         return -1;
 465 }
 466
 467 /*
 468  * We're anal about diff header consistency, to make
 469  * sure that we don't end up having strange ambiguous
 470  * patches floating around.
 471  *
 472  * As a result, gitdiff_{old|new}name() will check
 473  * their names against any previous information, just
 474  * to make sure..
 475  */
 476 static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
 477 {
 478         if (!orig_name && !isnull)
 479                 return find_name(line, NULL, p_value, TERM_TAB);
 480
 481         if (orig_name) {
 482                 int len;
 483                 const char *name;
 484                 char *another;
 485                 name = orig_name;
 486                 len = strlen(name);
 487                 if (isnull)
 488                         die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
 489                 another = find_name(line, NULL, p_value, TERM_TAB);
 490                 if (!another || memcmp(another, name, len))
 491                         die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
 492                 free(another);
 493                 return orig_name;
 494         }
 495         else {
 496                 /* expect "/dev/null" */
 497                 if (memcmp("/dev/null", line, 9) || line[9] != '\n')
 498                         die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
 499                 return NULL;
 500         }
 501 }
 502
 503 static int gitdiff_oldname(const char *line, struct patch *patch)
 504 {
 505         patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
 506         return 0;
 507 }
 508
 509 static int gitdiff_newname(const char *line, struct patch *patch)
 510 {
 511         patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
 512         return 0;
 513 }
 514
 515 static int gitdiff_oldmode(const char *line, struct patch *patch)
 516 {
 517         patch->old_mode = strtoul(line, NULL, 8);
 518         return 0;
 519 }
 520
 521 static int gitdiff_newmode(const char *line, struct patch *patch)
 522 {
 523         patch->new_mode = strtoul(line, NULL, 8);
 524         return 0;
 525 }
 526
 527 static int gitdiff_delete(const char *line, struct patch *patch)
 528 {
 529         patch->is_delete = 1;
 530         patch->old_name = patch->def_name;
 531         return gitdiff_oldmode(line, patch);
 532 }
 533
 534 static int gitdiff_newfile(const char *line, struct patch *patch)
 535 {
 536         patch->is_new = 1;
 537         patch->new_name = patch->def_name;
 538         return gitdiff_newmode(line, patch);
 539 }
 540
 541 static int gitdiff_copysrc(const char *line, struct patch *patch)
 542 {
 543         patch->is_copy = 1;
 544         patch->old_name = find_name(line, NULL, 0, 0);
 545         return 0;
 546 }
 547
 548 static int gitdiff_copydst(const char *line, struct patch *patch)
 549 {
 550         patch->is_copy = 1;
 551         patch->new_name = find_name(line, NULL, 0, 0);
 552         return 0;
 553 }
 554
 555 static int gitdiff_renamesrc(const char *line, struct patch *patch)
 556 {
 557         patch->is_rename = 1;
 558         patch->old_name = find_name(line, NULL, 0, 0);
 559         return 0;
 560 }
 561
 562 static int gitdiff_renamedst(const char *line, struct patch *patch)
 563 {
 564         patch->is_rename = 1;
 565         patch->new_name = find_name(line, NULL, 0, 0);
 566         return 0;
 567 }
 568
 569 static int gitdiff_similarity(const char *line, struct patch *patch)
 570 {
 571         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 572                 patch->score = 0;
 573         return 0;
 574 }
 575
 576 static int gitdiff_dissimilarity(const char *line, struct patch *patch)
 577 {
 578         if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 579                 patch->score = 0;
 580         return 0;
 581 }
 582
 583 static int gitdiff_index(const char *line, struct patch *patch)
 584 {
 585         /*
 586          * index line is N hexadecimal, "..", N hexadecimal,
 587          * and optional space with octal mode.
 588          */
 589         const char *ptr, *eol;
 590         int len;
 591
 592         ptr = strchr(line, '.');
 593         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
 594                 return 0;
 595         len = ptr - line;
 596         memcpy(patch->old_sha1_prefix, line, len);
 597         patch->old_sha1_prefix[len] = 0;
 598
 599         line = ptr + 2;
 600         ptr = strchr(line, ' ');
 601         eol = strchr(line, '\n');
 602
 603         if (!ptr || eol < ptr)
 604                 ptr = eol;
 605         len = ptr - line;
 606
 607         if (40 < len)
 608                 return 0;
 609         memcpy(patch->new_sha1_prefix, line, len);
 610         patch->new_sha1_prefix[len] = 0;
 611         if (*ptr == ' ')
 612                 patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
 613         return 0;
 614 }
 615
 616 /*
 617  * This is normal for a diff that doesn't change anything: we'll fall through
 618  * into the next diff. Tell the parser to break out.
 619  */
 620 static int gitdiff_unrecognized(const char *line, struct patch *patch)
 621 {
 622         return -1;
 623 }
 624
 625 static const char *stop_at_slash(const char *line, int llen)
 626 {
 627         int i;
 628
 629         for (i = 0; i < llen; i++) {
 630                 int ch = line[i];
 631                 if (ch == '/')
 632                         return line + i;
 633         }
 634         return NULL;
 635 }
 636
 637 /*
 638  * This is to extract the same name that appears on "diff --git"
 639  * line.  We do not find and return anything if it is a rename
 640  * patch, and it is OK because we will find the name elsewhere.
 641  * We need to reliably find name only when it is mode-change only,
 642  * creation or deletion of an empty file.  In any of these cases,
 643  * both sides are the same name under a/ and b/ respectively.
 644  */
 645 static char *git_header_name(char *line, int llen)
 646 {
 647         const char *name;
 648         const char *second = NULL;
 649         size_t len;
 650
 651         line += strlen("diff --git ");
 652         llen -= strlen("diff --git ");
 653
 654         if (*line == '"') {
 655                 const char *cp;
 656                 struct strbuf first;
 657                 struct strbuf sp;
 658
 659                 strbuf_init(&first, 0);
 660                 strbuf_init(&sp, 0);
 661
 662                 if (unquote_c_style(&first, line, &second))
 663                         goto free_and_fail1;
 664
 665                 /* advance to the first slash */
 666                 cp = stop_at_slash(first.buf, first.len);
 667                 /* we do not accept absolute paths */
 668                 if (!cp || cp == first.buf)
 669                         goto free_and_fail1;
 670                 strbuf_remove(&first, 0, cp + 1 - first.buf);
 671
 672                 /*
 673                  * second points at one past closing dq of name.
 674                  * find the second name.
 675                  */
 676                 while ((second < line + llen) && isspace(*second))
 677                         second++;
 678
 679                 if (line + llen <= second)
 680                         goto free_and_fail1;
 681                 if (*second == '"') {
 682                         if (unquote_c_style(&sp, second, NULL))
 683                                 goto free_and_fail1;
 684                         cp = stop_at_slash(sp.buf, sp.len);
 685                         if (!cp || cp == sp.buf)
 686                                 goto free_and_fail1;
 687                         /* They must match, otherwise ignore */
 688                         if (strcmp(cp + 1, first.buf))
 689                                 goto free_and_fail1;
 690                         strbuf_release(&sp);
 691                         return strbuf_detach(&first, NULL);
 692                 }
 693
 694                 /* unquoted second */
 695                 cp = stop_at_slash(second, line + llen - second);
 696                 if (!cp || cp == second)
 697                         goto free_and_fail1;
 698                 cp++;
 699                 if (line + llen - cp != first.len + 1 ||
 700                     memcmp(first.buf, cp, first.len))
 701                         goto free_and_fail1;
 702                 return strbuf_detach(&first, NULL);
 703
 704         free_and_fail1:
 705                 strbuf_release(&first);
 706                 strbuf_release(&sp);
 707                 return NULL;
 708         }
 709
 710         /* unquoted first name */
 711         name = stop_at_slash(line, llen);
 712         if (!name || name == line)
 713                 return NULL;
 714         name++;
 715
 716         /*
 717          * since the first name is unquoted, a dq if exists must be
 718          * the beginning of the second name.
 719          */
 720         for (second = name; second < line + llen; second++) {
 721                 if (*second == '"') {
 722                         struct strbuf sp;
 723                         const char *np;
 724
 725                         strbuf_init(&sp, 0);
 726                         if (unquote_c_style(&sp, second, NULL))
 727                                 goto free_and_fail2;
 728
 729                         np = stop_at_slash(sp.buf, sp.len);
 730                         if (!np || np == sp.buf)
 731                                 goto free_and_fail2;
 732                         np++;
 733
 734                         len = sp.buf + sp.len - np;
 735                         if (len < second - name &&
 736                             !strncmp(np, name, len) &&
 737                             isspace(name[len])) {
 738                                 /* Good */
 739                                 strbuf_remove(&sp, 0, np - sp.buf);
 740                                 return strbuf_detach(&sp, NULL);
 741                         }
 742
 743                 free_and_fail2:
 744                         strbuf_release(&sp);
 745                         return NULL;
 746                 }
 747         }
 748
 749         /*
 750          * Accept a name only if it shows up twice, exactly the same
 751          * form.
 752          */
 753         for (len = 0 ; ; len++) {
 754                 switch (name[len]) {
 755                 default:
 756                         continue;
 757                 case '\n':
 758                         return NULL;
 759                 case '\t': case ' ':
 760                         second = name+len;
 761                         for (;;) {
 762                                 char c = *second++;
 763                                 if (c == '\n')
 764                                         return NULL;
 765                                 if (c == '/')
 766                                         break;
 767                         }
 768                         if (second[len] == '\n' && !memcmp(name, second, len)) {
 769                                 return xmemdupz(name, len);
 770                         }
 771                 }
 772         }
 773 }
 774
 775 /* Verify that we recognize the lines following a git header */
 776 static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
 777 {
 778         unsigned long offset;
 779
 780         /* A git diff has explicit new/delete information, so we don't guess */
 781         patch->is_new = 0;
 782         patch->is_delete = 0;
 783
 784         /*
 785          * Some things may not have the old name in the
 786          * rest of the headers anywhere (pure mode changes,
 787          * or removing or adding empty files), so we get
 788          * the default name from the header.
 789          */
 790         patch->def_name = git_header_name(line, len);
 791
 792         line += len;
 793         size -= len;
 794         linenr++;
 795         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
 796                 static const struct opentry {
 797                         const char *str;
 798                         int (*fn)(const char *, struct patch *);
 799                 } optable[] = {
 800                         { "@@ -", gitdiff_hdrend },
 801                         { "--- ", gitdiff_oldname },
 802                         { "+++ ", gitdiff_newname },
 803                         { "old mode ", gitdiff_oldmode },
 804                         { "new mode ", gitdiff_newmode },
 805                         { "deleted file mode ", gitdiff_delete },
 806                         { "new file mode ", gitdiff_newfile },
 807                         { "copy from ", gitdiff_copysrc },
 808                         { "copy to ", gitdiff_copydst },
 809                         { "rename old ", gitdiff_renamesrc },
 810                         { "rename new ", gitdiff_renamedst },
 811                         { "rename from ", gitdiff_renamesrc },
 812                         { "rename to ", gitdiff_renamedst },
 813                         { "similarity index ", gitdiff_similarity },
 814                         { "dissimilarity index ", gitdiff_dissimilarity },
 815                         { "index ", gitdiff_index },
 816                         { "", gitdiff_unrecognized },
 817                 };
 818                 int i;
 819
 820                 len = linelen(line, size);
 821                 if (!len || line[len-1] != '\n')
 822                         break;
 823                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
 824                         const struct opentry *p = optable + i;
 825                         int oplen = strlen(p->str);
 826                         if (len < oplen || memcmp(p->str, line, oplen))
 827                                 continue;
 828                         if (p->fn(line + oplen, patch) < 0)
 829                                 return offset;
 830                         break;
 831                 }
 832         }
 833
 834         return offset;
 835 }
 836
 837 static int parse_num(const char *line, unsigned long *p)
 838 {
 839         char *ptr;
 840
 841         if (!isdigit(*line))
 842                 return 0;
 843         *p = strtoul(line, &ptr, 10);
 844         return ptr - line;
 845 }
 846
 847 static int parse_range(const char *line, int len, int offset, const char *expect,
 848                        unsigned long *p1, unsigned long *p2)
 849 {
 850         int digits, ex;
 851
 852         if (offset < 0 || offset >= len)
 853                 return -1;
 854         line += offset;
 855         len -= offset;
 856
 857         digits = parse_num(line, p1);
 858         if (!digits)
 859                 return -1;
 860
 861         offset += digits;
 862         line += digits;
 863         len -= digits;
 864
 865         *p2 = 1;
 866         if (*line == ',') {
 867                 digits = parse_num(line+1, p2);
 868                 if (!digits)
 869                         return -1;
 870
 871                 offset += digits+1;
 872                 line += digits+1;
 873                 len -= digits+1;
 874         }
 875
 876         ex = strlen(expect);
 877         if (ex > len)
 878                 return -1;
 879         if (memcmp(line, expect, ex))
 880                 return -1;
 881
 882         return offset + ex;
 883 }
 884
 885 /*
 886  * Parse a unified diff fragment header of the
 887  * form "@@ -a,b +c,d @@"
 888  */
 889 static int parse_fragment_header(char *line, int len, struct fragment *fragment)
 890 {
 891         int offset;
 892
 893         if (!len || line[len-1] != '\n')
 894                 return -1;
 895
 896         /* Figure out the number of lines in a fragment */
 897         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
 898         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 899
 900         return offset;
 901 }
 902
 903 static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
 904 {
 905         unsigned long offset, len;
 906
 907         patch->is_toplevel_relative = 0;
 908         patch->is_rename = patch->is_copy = 0;
 909         patch->is_new = patch->is_delete = -1;
 910         patch->old_mode = patch->new_mode = 0;
 911         patch->old_name = patch->new_name = NULL;
 912         for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
 913                 unsigned long nextlen;
 914
 915                 len = linelen(line, size);
 916                 if (!len)
 917                         break;
 918
 919                 /* Testing this early allows us to take a few shortcuts.. */
 920                 if (len < 6)
 921                         continue;
 922
 923                 /*
 924                  * Make sure we don't find any unconnected patch fragments.
 925                  * That's a sign that we didn't find a header, and that a
 926                  * patch has become corrupted/broken up.
 927                  */
 928                 if (!memcmp("@@ -", line, 4)) {
 929                         struct fragment dummy;
 930                         if (parse_fragment_header(line, len, &dummy) < 0)
 931                                 continue;
 932                         die("patch fragment without header at line %d: %.*s",
 933                             linenr, (int)len-1, line);
 934                 }
 935
 936                 if (size < len + 6)
 937                         break;
 938
 939                 /*
 940                  * Git patch? It might not have a real patch, just a rename
 941                  * or mode change, so we handle that specially
 942                  */
 943                 if (!memcmp("diff --git ", line, 11)) {
 944                         int git_hdr_len = parse_git_header(line, len, size, patch);
 945                         if (git_hdr_len <= len)
 946                                 continue;
 947                         if (!patch->old_name && !patch->new_name) {
 948                                 if (!patch->def_name)
 949                                         die("git diff header lacks filename information (line %d)", linenr);
 950                                 patch->old_name = patch->new_name = patch->def_name;
 951                         }
 952                         patch->is_toplevel_relative = 1;
 953                         *hdrsize = git_hdr_len;
 954                         return offset;
 955                 }
 956
 957                 /* --- followed by +++ ? */
 958                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
 959                         continue;
 960
 961                 /*
 962                  * We only accept unified patches, so we want it to
 963                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
 964                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
 965                  */
 966                 nextlen = linelen(line + len, size - len);
 967                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
 968                         continue;
 969
 970                 /* Ok, we'll consider it a patch */
 971                 parse_traditional_patch(line, line+len, patch);
 972                 *hdrsize = len + nextlen;
 973                 linenr += 2;
 974                 return offset;
 975         }
 976         return -1;
 977 }
 978
 979 static void check_whitespace(const char *line, int len, unsigned ws_rule)
 980 {
 981         char *err;
 982         unsigned result = check_and_emit_line(line + 1, len - 1, ws_rule,
 983             NULL, NULL, NULL, NULL);
 984         if (!result)
 985                 return;
 986
 987         whitespace_error++;
 988         if (squelch_whitespace_errors &&
 989             squelch_whitespace_errors < whitespace_error)
 990                 ;
 991         else {
 992                 err = whitespace_error_string(result);
 993                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
 994                      patch_input_file, linenr, err, len - 2, line + 1);
 995                 free(err);
 996         }
 997 }
 998
 999 /*
1000  * Parse a unified diff. Note that this really needs to parse each
1001  * fragment separately, since the only way to know the difference
1002  * between a "---" that is part of a patch, and a "---" that starts
1003  * the next patch is to look at the line counts..
1004  */
1005 static int parse_fragment(char *line, unsigned long size,
1006                           struct patch *patch, struct fragment *fragment)
1007 {
1008         int added, deleted;
1009         int len = linelen(line, size), offset;
1010         unsigned long oldlines, newlines;
1011         unsigned long leading, trailing;
1012
1013         offset = parse_fragment_header(line, len, fragment);
1014         if (offset < 0)
1015                 return -1;
1016         oldlines = fragment->oldlines;
1017         newlines = fragment->newlines;
1018         leading = 0;
1019         trailing = 0;
1020
1021         /* Parse the thing.. */
1022         line += len;
1023         size -= len;
1024         linenr++;
1025         added = deleted = 0;
1026         for (offset = len;
1027              0 < size;
1028              offset += len, size -= len, line += len, linenr++) {
1029                 if (!oldlines && !newlines)
1030                         break;
1031                 len = linelen(line, size);
1032                 if (!len || line[len-1] != '\n')
1033                         return -1;
1034                 switch (*line) {
1035                 default:
1036                         return -1;
1037                 case '\n': /* newer GNU diff, an empty context line */
1038                 case ' ':
1039                         oldlines--;
1040                         newlines--;
1041                         if (!deleted && !added)
1042                                 leading++;
1043                         trailing++;
1044                         break;
1045                 case '-':
1046                         if (apply_in_reverse &&
1047                             ws_error_action != nowarn_ws_error)
1048                                 check_whitespace(line, len, patch->ws_rule);
1049                         deleted++;
1050                         oldlines--;
1051                         trailing = 0;
1052                         break;
1053                 case '+':
1054                         if (!apply_in_reverse &&
1055                             ws_error_action != nowarn_ws_error)
1056                                 check_whitespace(line, len, patch->ws_rule);
1057                         added++;
1058                         newlines--;
1059                         trailing = 0;
1060                         break;
1061
1062                 /*
1063                  * We allow "\ No newline at end of file". Depending
1064                  * on locale settings when the patch was produced we
1065                  * don't know what this line looks like. The only
1066                  * thing we do know is that it begins with "\ ".
1067                  * Checking for 12 is just for sanity check -- any
1068                  * l10n of "\ No newline..." is at least that long.
1069                  */
1070                 case '\\':
1071                         if (len < 12 || memcmp(line, "\\ ", 2))
1072                                 return -1;
1073                         break;
1074                 }
1075         }
1076         if (oldlines || newlines)
1077                 return -1;
1078         fragment->leading = leading;
1079         fragment->trailing = trailing;
1080
1081         /*
1082          * If a fragment ends with an incomplete line, we failed to include
1083          * it in the above loop because we hit oldlines == newlines == 0
1084          * before seeing it.
1085          */
1086         if (12 < size && !memcmp(line, "\\ ", 2))
1087                 offset += linelen(line, size);
1088
1089         patch->lines_added += added;
1090         patch->lines_deleted += deleted;
1091
1092         if (0 < patch->is_new && oldlines)
1093                 return error("new file depends on old contents");
1094         if (0 < patch->is_delete && newlines)
1095                 return error("deleted file still has contents");
1096         return offset;
1097 }
1098
1099 static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1100 {
1101         unsigned long offset = 0;
1102         unsigned long oldlines = 0, newlines = 0, context = 0;
1103         struct fragment **fragp = &patch->fragments;
1104
1105         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1106                 struct fragment *fragment;
1107                 int len;
1108
1109                 fragment = xcalloc(1, sizeof(*fragment));
1110                 len = parse_fragment(line, size, patch, fragment);
1111                 if (len <= 0)
1112                         die("corrupt patch at line %d", linenr);
1113                 fragment->patch = line;
1114                 fragment->size = len;
1115                 oldlines += fragment->oldlines;
1116                 newlines += fragment->newlines;
1117                 context += fragment->leading + fragment->trailing;
1118
1119                 *fragp = fragment;
1120                 fragp = &fragment->next;
1121
1122                 offset += len;
1123                 line += len;
1124                 size -= len;
1125         }
1126
1127         /*
1128          * If something was removed (i.e. we have old-lines) it cannot
1129          * be creation, and if something was added it cannot be
1130          * deletion.  However, the reverse is not true; --unified=0
1131          * patches that only add are not necessarily creation even
1132          * though they do not have any old lines, and ones that only
1133          * delete are not necessarily deletion.
1134          *
1135          * Unfortunately, a real creation/deletion patch do _not_ have
1136          * any context line by definition, so we cannot safely tell it
1137          * apart with --unified=0 insanity.  At least if the patch has
1138          * more than one hunk it is not creation or deletion.
1139          */
1140         if (patch->is_new < 0 &&
1141             (oldlines || (patch->fragments && patch->fragments->next)))
1142                 patch->is_new = 0;
1143         if (patch->is_delete < 0 &&
1144             (newlines || (patch->fragments && patch->fragments->next)))
1145                 patch->is_delete = 0;
1146         if (!unidiff_zero || context) {
1147                 /* If the user says the patch is not generated with
1148                  * --unified=0, or if we have seen context lines,
1149                  * then not having oldlines means the patch is creation,
1150                  * and not having newlines means the patch is deletion.
1151                  */
1152                 if (patch->is_new < 0 && !oldlines) {
1153                         patch->is_new = 1;
1154                         patch->old_name = NULL;
1155                 }
1156                 if (patch->is_delete < 0 && !newlines) {
1157                         patch->is_delete = 1;
1158                         patch->new_name = NULL;
1159                 }
1160         }
1161
1162         if (0 < patch->is_new && oldlines)
1163                 die("new file %s depends on old contents", patch->new_name);
1164         if (0 < patch->is_delete && newlines)
1165                 die("deleted file %s still has contents", patch->old_name);
1166         if (!patch->is_delete && !newlines && context)
1167                 fprintf(stderr, "** warning: file %s becomes empty but "
1168                         "is not deleted\n", patch->new_name);
1169
1170         return offset;
1171 }
1172
1173 static inline int metadata_changes(struct patch *patch)
1174 {
1175         return  patch->is_rename > 0 ||
1176                 patch->is_copy > 0 ||
1177                 patch->is_new > 0 ||
1178                 patch->is_delete ||
1179                 (patch->old_mode && patch->new_mode &&
1180                  patch->old_mode != patch->new_mode);
1181 }
1182
1183 static char *inflate_it(const void *data, unsigned long size,
1184                         unsigned long inflated_size)
1185 {
1186         z_stream stream;
1187         void *out;
1188         int st;
1189
1190         memset(&stream, 0, sizeof(stream));
1191
1192         stream.next_in = (unsigned char *)data;
1193         stream.avail_in = size;
1194         stream.next_out = out = xmalloc(inflated_size);
1195         stream.avail_out = inflated_size;
1196         inflateInit(&stream);
1197         st = inflate(&stream, Z_FINISH);
1198         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1199                 free(out);
1200                 return NULL;
1201         }
1202         return out;
1203 }
1204
1205 static struct fragment *parse_binary_hunk(char **buf_p,
1206                                           unsigned long *sz_p,
1207                                           int *status_p,
1208                                           int *used_p)
1209 {
1210         /*
1211          * Expect a line that begins with binary patch method ("literal"
1212          * or "delta"), followed by the length of data before deflating.
1213          * a sequence of 'length-byte' followed by base-85 encoded data
1214          * should follow, terminated by a newline.
1215          *
1216          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1217          * and we would limit the patch line to 66 characters,
1218          * so one line can fit up to 13 groups that would decode
1219          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1220          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1221          */
1222         int llen, used;
1223         unsigned long size = *sz_p;
1224         char *buffer = *buf_p;
1225         int patch_method;
1226         unsigned long origlen;
1227         char *data = NULL;
1228         int hunk_size = 0;
1229         struct fragment *frag;
1230
1231         llen = linelen(buffer, size);
1232         used = llen;
1233
1234         *status_p = 0;
1235
1236         if (!prefixcmp(buffer, "delta ")) {
1237                 patch_method = BINARY_DELTA_DEFLATED;
1238                 origlen = strtoul(buffer + 6, NULL, 10);
1239         }
1240         else if (!prefixcmp(buffer, "literal ")) {
1241                 patch_method = BINARY_LITERAL_DEFLATED;
1242                 origlen = strtoul(buffer + 8, NULL, 10);
1243         }
1244         else
1245                 return NULL;
1246
1247         linenr++;
1248         buffer += llen;
1249         while (1) {
1250                 int byte_length, max_byte_length, newsize;
1251                 llen = linelen(buffer, size);
1252                 used += llen;
1253                 linenr++;
1254                 if (llen == 1) {
1255                         /* consume the blank line */
1256                         buffer++;
1257                         size--;
1258                         break;
1259                 }
1260                 /*
1261                  * Minimum line is "A00000\n" which is 7-byte long,
1262                  * and the line length must be multiple of 5 plus 2.
1263                  */
1264                 if ((llen < 7) || (llen-2) % 5)
1265                         goto corrupt;
1266                 max_byte_length = (llen - 2) / 5 * 4;
1267                 byte_length = *buffer;
1268                 if ('A' <= byte_length && byte_length <= 'Z')
1269                         byte_length = byte_length - 'A' + 1;
1270                 else if ('a' <= byte_length && byte_length <= 'z')
1271                         byte_length = byte_length - 'a' + 27;
1272                 else
1273                         goto corrupt;
1274                 /* if the input length was not multiple of 4, we would
1275                  * have filler at the end but the filler should never
1276                  * exceed 3 bytes
1277                  */
1278                 if (max_byte_length < byte_length ||
1279                     byte_length <= max_byte_length - 4)
1280                         goto corrupt;
1281                 newsize = hunk_size + byte_length;
1282                 data = xrealloc(data, newsize);
1283                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1284                         goto corrupt;
1285                 hunk_size = newsize;
1286                 buffer += llen;
1287                 size -= llen;
1288         }
1289
1290         frag = xcalloc(1, sizeof(*frag));
1291         frag->patch = inflate_it(data, hunk_size, origlen);
1292         if (!frag->patch)
1293                 goto corrupt;
1294         free(data);
1295         frag->size = origlen;
1296         *buf_p = buffer;
1297         *sz_p = size;
1298         *used_p = used;
1299         frag->binary_patch_method = patch_method;
1300         return frag;
1301
1302  corrupt:
1303         free(data);
1304         *status_p = -1;
1305         error("corrupt binary patch at line %d: %.*s",
1306               linenr-1, llen-1, buffer);
1307         return NULL;
1308 }
1309
1310 static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1311 {
1312         /*
1313          * We have read "GIT binary patch\n"; what follows is a line
1314          * that says the patch method (currently, either "literal" or
1315          * "delta") and the length of data before deflating; a
1316          * sequence of 'length-byte' followed by base-85 encoded data
1317          * follows.
1318          *
1319          * When a binary patch is reversible, there is another binary
1320          * hunk in the same format, starting with patch method (either
1321          * "literal" or "delta") with the length of data, and a sequence
1322          * of length-byte + base-85 encoded data, terminated with another
1323          * empty line.  This data, when applied to the postimage, produces
1324          * the preimage.
1325          */
1326         struct fragment *forward;
1327         struct fragment *reverse;
1328         int status;
1329         int used, used_1;
1330
1331         forward = parse_binary_hunk(&buffer, &size, &status, &used);
1332         if (!forward && !status)
1333                 /* there has to be one hunk (forward hunk) */
1334                 return error("unrecognized binary patch at line %d", linenr-1);
1335         if (status)
1336                 /* otherwise we already gave an error message */
1337                 return status;
1338
1339         reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1340         if (reverse)
1341                 used += used_1;
1342         else if (status) {
1343                 /*
1344                  * Not having reverse hunk is not an error, but having
1345                  * a corrupt reverse hunk is.
1346                  */
1347                 free((void*) forward->patch);
1348                 free(forward);
1349                 return status;
1350         }
1351         forward->next = reverse;
1352         patch->fragments = forward;
1353         patch->is_binary = 1;
1354         return used;
1355 }
1356
1357 static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1358 {
1359         int hdrsize, patchsize;
1360         int offset = find_header(buffer, size, &hdrsize, patch);
1361
1362         if (offset < 0)
1363                 return offset;
1364
1365         patch->ws_rule = whitespace_rule(patch->new_name
1366                                          ? patch->new_name
1367                                          : patch->old_name);
1368
1369         patchsize = parse_single_patch(buffer + offset + hdrsize,
1370                                        size - offset - hdrsize, patch);
1371
1372         if (!patchsize) {
1373                 static const char *binhdr[] = {
1374                         "Binary files ",
1375                         "Files ",
1376                         NULL,
1377                 };
1378                 static const char git_binary[] = "GIT binary patch\n";
1379                 int i;
1380                 int hd = hdrsize + offset;
1381                 unsigned long llen = linelen(buffer + hd, size - hd);
1382
1383                 if (llen == sizeof(git_binary) - 1 &&
1384                     !memcmp(git_binary, buffer + hd, llen)) {
1385                         int used;
1386                         linenr++;
1387                         used = parse_binary(buffer + hd + llen,
1388                                             size - hd - llen, patch);
1389                         if (used)
1390                                 patchsize = used + llen;
1391                         else
1392                                 patchsize = 0;
1393                 }
1394                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1395                         for (i = 0; binhdr[i]; i++) {
1396                                 int len = strlen(binhdr[i]);
1397                                 if (len < size - hd &&
1398                                     !memcmp(binhdr[i], buffer + hd, len)) {
1399                                         linenr++;
1400                                         patch->is_binary = 1;
1401                                         patchsize = llen;
1402                                         break;
1403                                 }
1404                         }
1405                 }
1406
1407                 /* Empty patch cannot be applied if it is a text patch
1408                  * without metadata change.  A binary patch appears
1409                  * empty to us here.
1410                  */
1411                 if ((apply || check) &&
1412                     (!patch->is_binary && !metadata_changes(patch)))
1413                         die("patch with only garbage at line %d", linenr);
1414         }
1415
1416         return offset + hdrsize + patchsize;
1417 }
1418
1419 #define swap(a,b) myswap((a),(b),sizeof(a))
1420
1421 #define myswap(a, b, size) do {         \
1422         unsigned char mytmp[size];      \
1423         memcpy(mytmp, &a, size);                \
1424         memcpy(&a, &b, size);           \
1425         memcpy(&b, mytmp, size);                \
1426 } while (0)
1427
1428 static void reverse_patches(struct patch *p)
1429 {
1430         for (; p; p = p->next) {
1431                 struct fragment *frag = p->fragments;
1432
1433                 swap(p->new_name, p->old_name);
1434                 swap(p->new_mode, p->old_mode);
1435                 swap(p->is_new, p->is_delete);
1436                 swap(p->lines_added, p->lines_deleted);
1437                 swap(p->old_sha1_prefix, p->new_sha1_prefix);
1438
1439                 for (; frag; frag = frag->next) {
1440                         swap(frag->newpos, frag->oldpos);
1441                         swap(frag->newlines, frag->oldlines);
1442                 }
1443         }
1444 }
1445
1446 static const char pluses[] =
1447 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1448 static const char minuses[]=
1449 "----------------------------------------------------------------------";
1450
1451 static void show_stats(struct patch *patch)
1452 {
1453         struct strbuf qname;
1454         char *cp = patch->new_name ? patch->new_name : patch->old_name;
1455         int max, add, del;
1456
1457         strbuf_init(&qname, 0);
1458         quote_c_style(cp, &qname, NULL, 0);
1459
1460         /*
1461          * "scale" the filename
1462          */
1463         max = max_len;
1464         if (max > 50)
1465                 max = 50;
1466
1467         if (qname.len > max) {
1468                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
1469                 if (!cp)
1470                         cp = qname.buf + qname.len + 3 - max;
1471                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
1472         }
1473
1474         if (patch->is_binary) {
1475                 printf(" %-*s |  Bin\n", max, qname.buf);
1476                 strbuf_release(&qname);
1477                 return;
1478         }
1479
1480         printf(" %-*s |", max, qname.buf);
1481         strbuf_release(&qname);
1482
1483         /*
1484          * scale the add/delete
1485          */
1486         max = max + max_change > 70 ? 70 - max : max_change;
1487         add = patch->lines_added;
1488         del = patch->lines_deleted;
1489
1490         if (max_change > 0) {
1491                 int total = ((add + del) * max + max_change / 2) / max_change;
1492                 add = (add * max + max_change / 2) / max_change;
1493                 del = total - add;
1494         }
1495         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
1496                 add, pluses, del, minuses);
1497 }
1498
1499 static int read_old_data(struct stat *st, const char *path, struct strbuf *buf)
1500 {
1501         switch (st->st_mode & S_IFMT) {
1502         case S_IFLNK:
1503                 strbuf_grow(buf, st->st_size);
1504                 if (readlink(path, buf->buf, st->st_size) != st->st_size)
1505                         return -1;
1506                 strbuf_setlen(buf, st->st_size);
1507                 return 0;
1508         case S_IFREG:
1509                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
1510                         return error("unable to open or read %s", path);
1511                 convert_to_git(path, buf->buf, buf->len, buf, 0);
1512                 return 0;
1513         default:
1514                 return -1;
1515         }
1516 }
1517
1518 static void update_pre_post_images(struct image *preimage,
1519                                    struct image *postimage,
1520                                    char *buf,
1521                                    size_t len)
1522 {
1523         int i, ctx;
1524         char *new, *old, *fixed;
1525         struct image fixed_preimage;
1526
1527         /*
1528          * Update the preimage with whitespace fixes.  Note that we
1529          * are not losing preimage->buf -- apply_one_fragment() will
1530          * free "oldlines".
1531          */
1532         prepare_image(&fixed_preimage, buf, len, 1);
1533         assert(fixed_preimage.nr == preimage->nr);
1534         for (i = 0; i < preimage->nr; i++)
1535                 fixed_preimage.line[i].flag = preimage->line[i].flag;
1536         free(preimage->line_allocated);
1537         *preimage = fixed_preimage;
1538
1539         /*
1540          * Adjust the common context lines in postimage, in place.
1541          * This is possible because whitespace fixing does not make
1542          * the string grow.
1543          */
1544         new = old = postimage->buf;
1545         fixed = preimage->buf;
1546         for (i = ctx = 0; i < postimage->nr; i++) {
1547                 size_t len = postimage->line[i].len;
1548                 if (!(postimage->line[i].flag & LINE_COMMON)) {
1549                         /* an added line -- no counterparts in preimage */
1550                         memmove(new, old, len);
1551                         old += len;
1552                         new += len;
1553                         continue;
1554                 }
1555
1556                 /* a common context -- skip it in the original postimage */
1557                 old += len;
1558
1559                 /* and find the corresponding one in the fixed preimage */
1560                 while (ctx < preimage->nr &&
1561                        !(preimage->line[ctx].flag & LINE_COMMON)) {
1562                         fixed += preimage->line[ctx].len;
1563                         ctx++;
1564                 }
1565                 if (preimage->nr <= ctx)
1566                         die("oops");
1567
1568                 /* and copy it in, while fixing the line length */
1569                 len = preimage->line[ctx].len;
1570                 memcpy(new, fixed, len);
1571                 new += len;
1572                 fixed += len;
1573                 postimage->line[i].len = len;
1574                 ctx++;
1575         }
1576
1577         /* Fix the length of the whole thing */
1578         postimage->len = new - postimage->buf;
1579 }
1580
1581 static int match_fragment(struct image *img,
1582                           struct image *preimage,
1583                           struct image *postimage,
1584                           unsigned long try,
1585                           int try_lno,
1586                           unsigned ws_rule,
1587                           int match_beginning, int match_end)
1588 {
1589         int i;
1590         char *fixed_buf, *buf, *orig, *target;
1591
1592         if (preimage->nr + try_lno > img->nr)
1593                 return 0;
1594
1595         if (match_beginning && try_lno)
1596                 return 0;
1597
1598         if (match_end && preimage->nr + try_lno != img->nr)
1599                 return 0;
1600
1601         /* Quick hash check */
1602         for (i = 0; i < preimage->nr; i++)
1603                 if (preimage->line[i].hash != img->line[try_lno + i].hash)
1604                         return 0;
1605
1606         /*
1607          * Do we have an exact match?  If we were told to match
1608          * at the end, size must be exactly at try+fragsize,
1609          * otherwise try+fragsize must be still within the preimage,
1610          * and either case, the old piece should match the preimage
1611          * exactly.
1612          */
1613         if ((match_end
1614              ? (try + preimage->len == img->len)
1615              : (try + preimage->len <= img->len)) &&
1616             !memcmp(img->buf + try, preimage->buf, preimage->len))
1617                 return 1;
1618
1619         if (ws_error_action != correct_ws_error)
1620                 return 0;
1621
1622         /*
1623          * The hunk does not apply byte-by-byte, but the hash says
1624          * it might with whitespace fuzz.
1625          */
1626         fixed_buf = xmalloc(preimage->len + 1);
1627         buf = fixed_buf;
1628         orig = preimage->buf;
1629         target = img->buf + try;
1630         for (i = 0; i < preimage->nr; i++) {
1631                 size_t fixlen; /* length after fixing the preimage */
1632                 size_t oldlen = preimage->line[i].len;
1633                 size_t tgtlen = img->line[try_lno + i].len;
1634                 size_t tgtfixlen; /* length after fixing the target line */
1635                 char tgtfixbuf[1024], *tgtfix;
1636                 int match;
1637
1638                 /* Try fixing the line in the preimage */
1639                 fixlen = ws_fix_copy(buf, orig, oldlen, ws_rule, NULL);
1640
1641                 /* Try fixing the line in the target */
1642                 if (sizeof(tgtfixbuf) < tgtlen)
1643                         tgtfix = tgtfixbuf;
1644                 else
1645                         tgtfix = xmalloc(tgtlen);
1646                 tgtfixlen = ws_fix_copy(tgtfix, target, tgtlen, ws_rule, NULL);
1647
1648                 /*
1649                  * If they match, either the preimage was based on
1650                  * a version before our tree fixed whitespace breakage,
1651                  * or we are lacking a whitespace-fix patch the tree
1652                  * the preimage was based on already had (i.e. target
1653                  * has whitespace breakage, the preimage doesn't).
1654                  * In either case, we are fixing the whitespace breakages
1655                  * so we might as well take the fix together with their
1656                  * real change.
1657                  */
1658                 match = (tgtfixlen == fixlen && !memcmp(tgtfix, buf, fixlen));
1659
1660                 if (tgtfix != tgtfixbuf)
1661                         free(tgtfix);
1662                 if (!match)
1663                         goto unmatch_exit;
1664
1665                 orig += oldlen;
1666                 buf += fixlen;
1667                 target += tgtlen;
1668         }
1669
1670         /*
1671          * Yes, the preimage is based on an older version that still
1672          * has whitespace breakages unfixed, and fixing them makes the
1673          * hunk match.  Update the context lines in the postimage.
1674          */
1675         update_pre_post_images(preimage, postimage,
1676                                fixed_buf, buf - fixed_buf);
1677         return 1;
1678
1679  unmatch_exit:
1680         free(fixed_buf);
1681         return 0;
1682 }
1683
1684 static int find_pos(struct image *img,
1685                     struct image *preimage,
1686                     struct image *postimage,
1687                     int line,
1688                     unsigned ws_rule,
1689                     int match_beginning, int match_end)
1690 {
1691         int i;
1692         unsigned long backwards, forwards, try;
1693         int backwards_lno, forwards_lno, try_lno;
1694
1695         if (preimage->nr > img->nr)
1696                 return -1;
1697
1698         /*
1699          * If match_begining or match_end is specified, there is no
1700          * point starting from a wrong line that will never match and
1701          * wander around and wait for a match at the specified end.
1702          */
1703         if (match_beginning)
1704                 line = 0;
1705         else if (match_end)
1706                 line = img->nr - preimage->nr;
1707
1708         if (line > img->nr)
1709                 line = img->nr;
1710
1711         try = 0;
1712         for (i = 0; i < line; i++)
1713                 try += img->line[i].len;
1714
1715         /*
1716          * There's probably some smart way to do this, but I'll leave
1717          * that to the smart and beautiful people. I'm simple and stupid.
1718          */
1719         backwards = try;
1720         backwards_lno = line;
1721         forwards = try;
1722         forwards_lno = line;
1723         try_lno = line;
1724
1725         for (i = 0; ; i++) {
1726                 if (match_fragment(img, preimage, postimage,
1727                                    try, try_lno, ws_rule,
1728                                    match_beginning, match_end))
1729                         return try_lno;
1730
1731         again:
1732                 if (backwards_lno == 0 && forwards_lno == img->nr)
1733                         break;
1734
1735                 if (i & 1) {
1736                         if (backwards_lno == 0) {
1737                                 i++;
1738                                 goto again;
1739                         }
1740                         backwards_lno--;
1741                         backwards -= img->line[backwards_lno].len;
1742                         try = backwards;
1743                         try_lno = backwards_lno;
1744                 } else {
1745                         if (forwards_lno == img->nr) {
1746                                 i++;
1747                                 goto again;
1748                         }
1749                         forwards += img->line[forwards_lno].len;
1750                         forwards_lno++;
1751                         try = forwards;
1752                         try_lno = forwards_lno;
1753                 }
1754
1755         }
1756         return -1;
1757 }
1758
1759 static void remove_first_line(struct image *img)
1760 {
1761         img->buf += img->line[0].len;
1762         img->len -= img->line[0].len;
1763         img->line++;
1764         img->nr--;
1765 }
1766
1767 static void remove_last_line(struct image *img)
1768 {
1769         img->len -= img->line[--img->nr].len;
1770 }
1771
1772 static void update_image(struct image *img,
1773                          int applied_pos,
1774                          struct image *preimage,
1775                          struct image *postimage)
1776 {
1777         /*
1778          * remove the copy of preimage at offset in img
1779          * and replace it with postimage
1780          */
1781         int i, nr;
1782         size_t remove_count, insert_count, applied_at = 0;
1783         char *result;
1784
1785         for (i = 0; i < applied_pos; i++)
1786                 applied_at += img->line[i].len;
1787
1788         remove_count = 0;
1789         for (i = 0; i < preimage->nr; i++)
1790                 remove_count += img->line[applied_pos + i].len;
1791         insert_count = postimage->len;
1792
1793         /* Adjust the contents */
1794         result = xmalloc(img->len + insert_count - remove_count + 1);
1795         memcpy(result, img->buf, applied_at);
1796         memcpy(result + applied_at, postimage->buf, postimage->len);
1797         memcpy(result + applied_at + postimage->len,
1798                img->buf + (applied_at + remove_count),
1799                img->len - (applied_at + remove_count));
1800         free(img->buf);
1801         img->buf = result;
1802         img->len += insert_count - remove_count;
1803         result[img->len] = '\0';
1804
1805         /* Adjust the line table */
1806         nr = img->nr + postimage->nr - preimage->nr;
1807         if (preimage->nr < postimage->nr) {
1808                 /*
1809                  * NOTE: this knows that we never call remove_first_line()
1810                  * on anything other than pre/post image.
1811                  */
1812                 img->line = xrealloc(img->line, nr * sizeof(*img->line));
1813                 img->line_allocated = img->line;
1814         }
1815         if (preimage->nr != postimage->nr)
1816                 memmove(img->line + applied_pos + postimage->nr,
1817                         img->line + applied_pos + preimage->nr,
1818                         (img->nr - (applied_pos + preimage->nr)) *
1819                         sizeof(*img->line));
1820         memcpy(img->line + applied_pos,
1821                postimage->line,
1822                postimage->nr * sizeof(*img->line));
1823         img->nr = nr;
1824 }
1825
1826 static int apply_one_fragment(struct image *img, struct fragment *frag,
1827                               int inaccurate_eof, unsigned ws_rule)
1828 {
1829         int match_beginning, match_end;
1830         const char *patch = frag->patch;
1831         int size = frag->size;
1832         char *old, *new, *oldlines, *newlines;
1833         int new_blank_lines_at_end = 0;
1834         unsigned long leading, trailing;
1835         int pos, applied_pos;
1836         struct image preimage;
1837         struct image postimage;
1838
1839         memset(&preimage, 0, sizeof(preimage));
1840         memset(&postimage, 0, sizeof(postimage));
1841         oldlines = xmalloc(size);
1842         newlines = xmalloc(size);
1843
1844         old = oldlines;
1845         new = newlines;
1846         while (size > 0) {
1847                 char first;
1848                 int len = linelen(patch, size);
1849                 int plen, added;
1850                 int added_blank_line = 0;
1851
1852                 if (!len)
1853                         break;
1854
1855                 /*
1856                  * "plen" is how much of the line we should use for
1857                  * the actual patch data. Normally we just remove the
1858                  * first character on the line, but if the line is
1859                  * followed by "\ No newline", then we also remove the
1860                  * last one (which is the newline, of course).
1861                  */
1862                 plen = len - 1;
1863                 if (len < size && patch[len] == '\\')
1864                         plen--;
1865                 first = *patch;
1866                 if (apply_in_reverse) {
1867                         if (first == '-')
1868                                 first = '+';
1869                         else if (first == '+')
1870                                 first = '-';
1871                 }
1872
1873                 switch (first) {
1874                 case '\n':
1875                         /* Newer GNU diff, empty context line */
1876                         if (plen < 0)
1877                                 /* ... followed by '\No newline'; nothing */
1878                                 break;
1879                         *old++ = '\n';
1880                         *new++ = '\n';
1881                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
1882                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
1883                         break;
1884                 case ' ':
1885                 case '-':
1886                         memcpy(old, patch + 1, plen);
1887                         add_line_info(&preimage, old, plen,
1888                                       (first == ' ' ? LINE_COMMON : 0));
1889                         old += plen;
1890                         if (first == '-')
1891                                 break;
1892                 /* Fall-through for ' ' */
1893                 case '+':
1894                         /* --no-add does not add new lines */
1895                         if (first == '+' && no_add)
1896                                 break;
1897
1898                         if (first != '+' ||
1899                             !whitespace_error ||
1900                             ws_error_action != correct_ws_error) {
1901                                 memcpy(new, patch + 1, plen);
1902                                 added = plen;
1903                         }
1904                         else {
1905                                 added = ws_fix_copy(new, patch + 1, plen, ws_rule, &applied_after_fixing_ws);
1906                         }
1907                         add_line_info(&postimage, new, added,
1908                                       (first == '+' ? 0 : LINE_COMMON));
1909                         new += added;
1910                         if (first == '+' &&
1911                             added == 1 && new[-1] == '\n')
1912                                 added_blank_line = 1;
1913                         break;
1914                 case '@': case '\\':
1915                         /* Ignore it, we already handled it */
1916                         break;
1917                 default:
1918                         if (apply_verbosely)
1919                                 error("invalid start of line: '%c'", first);
1920                         return -1;
1921                 }
1922                 if (added_blank_line)
1923                         new_blank_lines_at_end++;
1924                 else
1925                         new_blank_lines_at_end = 0;
1926                 patch += len;
1927                 size -= len;
1928         }
1929         if (inaccurate_eof &&
1930             old > oldlines && old[-1] == '\n' &&
1931             new > newlines && new[-1] == '\n') {
1932                 old--;
1933                 new--;
1934         }
1935
1936         leading = frag->leading;
1937         trailing = frag->trailing;
1938
1939         /*
1940          * A hunk to change lines at the beginning would begin with
1941          * @@ -1,L +N,M @@
1942          *
1943          * And a hunk to add to an empty file would begin with
1944          * @@ -0,0 +N,M @@
1945          *
1946          * In other words, a hunk that is (frag->oldpos <= 1) with or
1947          * without leading context must match at the beginning.
1948          */
1949         match_beginning = frag->oldpos <= 1;
1950
1951         /*
1952          * A hunk without trailing lines must match at the end.
1953          * However, we simply cannot tell if a hunk must match end
1954          * from the lack of trailing lines if the patch was generated
1955          * with unidiff without any context.
1956          */
1957         match_end = !unidiff_zero && !trailing;
1958
1959         pos = frag->newpos ? (frag->newpos - 1) : 0;
1960         preimage.buf = oldlines;
1961         preimage.len = old - oldlines;
1962         postimage.buf = newlines;
1963         postimage.len = new - newlines;
1964         preimage.line = preimage.line_allocated;
1965         postimage.line = postimage.line_allocated;
1966
1967         for (;;) {
1968
1969                 applied_pos = find_pos(img, &preimage, &postimage, pos,
1970                                        ws_rule, match_beginning, match_end);
1971
1972                 if (applied_pos >= 0)
1973                         break;
1974
1975                 /* Am I at my context limits? */
1976                 if ((leading <= p_context) && (trailing <= p_context))
1977                         break;
1978                 if (match_beginning || match_end) {
1979                         match_beginning = match_end = 0;
1980                         continue;
1981                 }
1982
1983                 /*
1984                  * Reduce the number of context lines; reduce both
1985                  * leading and trailing if they are equal otherwise
1986                  * just reduce the larger context.
1987                  */
1988                 if (leading >= trailing) {
1989                         remove_first_line(&preimage);
1990                         remove_first_line(&postimage);
1991                         pos--;
1992                         leading--;
1993                 }
1994                 if (trailing > leading) {
1995                         remove_last_line(&preimage);
1996                         remove_last_line(&postimage);
1997                         trailing--;
1998                 }
1999         }
2000
2001         if (applied_pos >= 0) {
2002                 if (ws_error_action == correct_ws_error &&
2003                     new_blank_lines_at_end &&
2004                     postimage.nr + applied_pos == img->nr) {
2005                         /*
2006                          * If the patch application adds blank lines
2007                          * at the end, and if the patch applies at the
2008                          * end of the image, remove those added blank
2009                          * lines.
2010                          */
2011                         while (new_blank_lines_at_end--)
2012                                 remove_last_line(&postimage);
2013                 }
2014
2015                 /*
2016                  * Warn if it was necessary to reduce the number
2017                  * of context lines.
2018                  */
2019                 if ((leading != frag->leading) ||
2020                     (trailing != frag->trailing))
2021                         fprintf(stderr, "Context reduced to (%ld/%ld)"
2022                                 " to apply fragment at %d\n",
2023                                 leading, trailing, applied_pos+1);
2024                 update_image(img, applied_pos, &preimage, &postimage);
2025         } else {
2026                 if (apply_verbosely)
2027                         error("while searching for:\n%.*s",
2028                               (int)(old - oldlines), oldlines);
2029         }
2030
2031         free(oldlines);
2032         free(newlines);
2033         free(preimage.line_allocated);
2034         free(postimage.line_allocated);
2035
2036         return (applied_pos < 0);
2037 }
2038
2039 static int apply_binary_fragment(struct image *img, struct patch *patch)
2040 {
2041         struct fragment *fragment = patch->fragments;
2042         unsigned long len;
2043         void *dst;
2044
2045         /* Binary patch is irreversible without the optional second hunk */
2046         if (apply_in_reverse) {
2047                 if (!fragment->next)
2048                         return error("cannot reverse-apply a binary patch "
2049                                      "without the reverse hunk to '%s'",
2050                                      patch->new_name
2051                                      ? patch->new_name : patch->old_name);
2052                 fragment = fragment->next;
2053         }
2054         switch (fragment->binary_patch_method) {
2055         case BINARY_DELTA_DEFLATED:
2056                 dst = patch_delta(img->buf, img->len, fragment->patch,
2057                                   fragment->size, &len);
2058                 if (!dst)
2059                         return -1;
2060                 clear_image(img);
2061                 img->buf = dst;
2062                 img->len = len;
2063                 return 0;
2064         case BINARY_LITERAL_DEFLATED:
2065                 clear_image(img);
2066                 img->len = fragment->size;
2067                 img->buf = xmalloc(img->len+1);
2068                 memcpy(img->buf, fragment->patch, img->len);
2069                 img->buf[img->len] = '\0';
2070                 return 0;
2071         }
2072         return -1;
2073 }
2074
2075 static int apply_binary(struct image *img, struct patch *patch)
2076 {
2077         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2078         unsigned char sha1[20];
2079
2080         /*
2081          * For safety, we require patch index line to contain
2082          * full 40-byte textual SHA1 for old and new, at least for now.
2083          */
2084         if (strlen(patch->old_sha1_prefix) != 40 ||
2085             strlen(patch->new_sha1_prefix) != 40 ||
2086             get_sha1_hex(patch->old_sha1_prefix, sha1) ||
2087             get_sha1_hex(patch->new_sha1_prefix, sha1))
2088                 return error("cannot apply binary patch to '%s' "
2089                              "without full index line", name);
2090
2091         if (patch->old_name) {
2092                 /*
2093                  * See if the old one matches what the patch
2094                  * applies to.
2095                  */
2096                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2097                 if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
2098                         return error("the patch applies to '%s' (%s), "
2099                                      "which does not match the "
2100                                      "current contents.",
2101                                      name, sha1_to_hex(sha1));
2102         }
2103         else {
2104                 /* Otherwise, the old one must be empty. */
2105                 if (img->len)
2106                         return error("the patch applies to an empty "
2107                                      "'%s' but it is not empty", name);
2108         }
2109
2110         get_sha1_hex(patch->new_sha1_prefix, sha1);
2111         if (is_null_sha1(sha1)) {
2112                 clear_image(img);
2113                 return 0; /* deletion patch */
2114         }
2115
2116         if (has_sha1_file(sha1)) {
2117                 /* We already have the postimage */
2118                 enum object_type type;
2119                 unsigned long size;
2120                 char *result;
2121
2122                 result = read_sha1_file(sha1, &type, &size);
2123                 if (!result)
2124                         return error("the necessary postimage %s for "
2125                                      "'%s' cannot be read",
2126                                      patch->new_sha1_prefix, name);
2127                 clear_image(img);
2128                 img->buf = result;
2129                 img->len = size;
2130         } else {
2131                 /*
2132                  * We have verified buf matches the preimage;
2133                  * apply the patch data to it, which is stored
2134                  * in the patch->fragments->{patch,size}.
2135                  */
2136                 if (apply_binary_fragment(img, patch))
2137                         return error("binary patch does not apply to '%s'",
2138                                      name);
2139
2140                 /* verify that the result matches */
2141                 hash_sha1_file(img->buf, img->len, blob_type, sha1);
2142                 if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
2143                         return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)",
2144                                 name, patch->new_sha1_prefix, sha1_to_hex(sha1));
2145         }
2146
2147         return 0;
2148 }
2149
2150 static int apply_fragments(struct image *img, struct patch *patch)
2151 {
2152         struct fragment *frag = patch->fragments;
2153         const char *name = patch->old_name ? patch->old_name : patch->new_name;
2154         unsigned ws_rule = patch->ws_rule;
2155         unsigned inaccurate_eof = patch->inaccurate_eof;
2156
2157         if (patch->is_binary)
2158                 return apply_binary(img, patch);
2159
2160         while (frag) {
2161                 if (apply_one_fragment(img, frag, inaccurate_eof, ws_rule)) {
2162                         error("patch failed: %s:%ld", name, frag->oldpos);
2163                         if (!apply_with_reject)
2164                                 return -1;
2165                         frag->rejected = 1;
2166                 }
2167                 frag = frag->next;
2168         }
2169         return 0;
2170 }
2171
2172 static int read_file_or_gitlink(struct cache_entry *ce, struct strbuf *buf)
2173 {
2174         if (!ce)
2175                 return 0;
2176
2177         if (S_ISGITLINK(ce->ce_mode)) {
2178                 strbuf_grow(buf, 100);
2179                 strbuf_addf(buf, "Subproject commit %s\n", sha1_to_hex(ce->sha1));
2180         } else {
2181                 enum object_type type;
2182                 unsigned long sz;
2183                 char *result;
2184
2185                 result = read_sha1_file(ce->sha1, &type, &sz);
2186                 if (!result)
2187                         return -1;
2188                 /* XXX read_sha1_file NUL-terminates */
2189                 strbuf_attach(buf, result, sz, sz + 1);
2190         }
2191         return 0;
2192 }
2193
2194 static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
2195 {
2196         struct strbuf buf;
2197         struct image image;
2198         size_t len;
2199         char *img;
2200
2201         strbuf_init(&buf, 0);
2202         if (cached) {
2203                 if (read_file_or_gitlink(ce, &buf))
2204                         return error("read of %s failed", patch->old_name);
2205         } else if (patch->old_name) {
2206                 if (S_ISGITLINK(patch->old_mode)) {
2207                         if (ce) {
2208                                 read_file_or_gitlink(ce, &buf);
2209                         } else {
2210                                 /*
2211                                  * There is no way to apply subproject
2212                                  * patch without looking at the index.
2213                                  */
2214                                 patch->fragments = NULL;
2215                         }
2216                 } else {
2217                         if (read_old_data(st, patch->old_name, &buf))
2218                                 return error("read of %s failed", patch->old_name);
2219                 }
2220         }
2221
2222         img = strbuf_detach(&buf, &len);
2223         prepare_image(&image, img, len, !patch->is_binary);
2224
2225         if (apply_fragments(&image, patch) < 0)
2226                 return -1; /* note with --reject this succeeds. */
2227         patch->result = image.buf;
2228         patch->resultsize = image.len;
2229         free(image.line_allocated);
2230
2231         if (0 < patch->is_delete && patch->resultsize)
2232                 return error("removal patch leaves file contents");
2233
2234         return 0;
2235 }
2236
2237 static int check_to_create_blob(const char *new_name, int ok_if_exists)
2238 {
2239         struct stat nst;
2240         if (!lstat(new_name, &nst)) {
2241                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
2242                         return 0;
2243                 /*
2244                  * A leading component of new_name might be a symlink
2245                  * that is going to be removed with this patch, but
2246                  * still pointing at somewhere that has the path.
2247                  * In such a case, path "new_name" does not exist as
2248                  * far as git is concerned.
2249                  */
2250                 if (has_symlink_leading_path(new_name, NULL))
2251                         return 0;
2252
2253                 return error("%s: already exists in working directory", new_name);
2254         }
2255         else if ((errno != ENOENT) && (errno != ENOTDIR))
2256                 return error("%s: %s", new_name, strerror(errno));
2257         return 0;
2258 }
2259
2260 static int verify_index_match(struct cache_entry *ce, struct stat *st)
2261 {
2262         if (S_ISGITLINK(ce->ce_mode)) {
2263                 if (!S_ISDIR(st->st_mode))
2264                         return -1;
2265                 return 0;
2266         }
2267         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID);
2268 }
2269
2270 static int check_patch(struct patch *patch, struct patch *prev_patch)
2271 {
2272         struct stat st;
2273         const char *old_name = patch->old_name;
2274         const char *new_name = patch->new_name;
2275         const char *name = old_name ? old_name : new_name;
2276         struct cache_entry *ce = NULL;
2277         int ok_if_exists;
2278
2279         patch->rejected = 1; /* we will drop this after we succeed */
2280
2281         /*
2282          * Make sure that we do not have local modifications from the
2283          * index when we are looking at the index.  Also make sure
2284          * we have the preimage file to be patched in the work tree,
2285          * unless --cached, which tells git to apply only in the index.
2286          */
2287         if (old_name) {
2288                 int stat_ret = 0;
2289                 unsigned st_mode = 0;
2290
2291                 if (!cached)
2292                         stat_ret = lstat(old_name, &st);
2293                 if (check_index) {
2294                         int pos = cache_name_pos(old_name, strlen(old_name));
2295                         if (pos < 0)
2296                                 return error("%s: does not exist in index",
2297                                              old_name);
2298                         ce = active_cache[pos];
2299                         if (stat_ret < 0) {
2300                                 struct checkout costate;
2301                                 if (errno != ENOENT)
2302                                         return error("%s: %s", old_name,
2303                                                      strerror(errno));
2304                                 /* checkout */
2305                                 costate.base_dir = "";
2306                                 costate.base_dir_len = 0;
2307                                 costate.force = 0;
2308                                 costate.quiet = 0;
2309                                 costate.not_new = 0;
2310                                 costate.refresh_cache = 1;
2311                                 if (checkout_entry(ce,
2312                                                    &costate,
2313                                                    NULL) ||
2314                                     lstat(old_name, &st))
2315                                         return -1;
2316                         }
2317                         if (!cached && verify_index_match(ce, &st))
2318                                 return error("%s: does not match index",
2319                                              old_name);
2320                         if (cached)
2321                                 st_mode = ce->ce_mode;
2322                 } else if (stat_ret < 0)
2323                         return error("%s: %s", old_name, strerror(errno));
2324
2325                 if (!cached)
2326                         st_mode = ce_mode_from_stat(ce, st.st_mode);
2327
2328                 if (patch->is_new < 0)
2329                         patch->is_new = 0;
2330                 if (!patch->old_mode)
2331                         patch->old_mode = st_mode;
2332                 if ((st_mode ^ patch->old_mode) & S_IFMT)
2333                         return error("%s: wrong type", old_name);
2334                 if (st_mode != patch->old_mode)
2335                         fprintf(stderr, "warning: %s has type %o, expected %o\n",
2336                                 old_name, st_mode, patch->old_mode);
2337         }
2338
2339         if (new_name && prev_patch && 0 < prev_patch->is_delete &&
2340             !strcmp(prev_patch->old_name, new_name))
2341                 /*
2342                  * A type-change diff is always split into a patch to
2343                  * delete old, immediately followed by a patch to
2344                  * create new (see diff.c::run_diff()); in such a case
2345                  * it is Ok that the entry to be deleted by the
2346                  * previous patch is still in the working tree and in
2347                  * the index.
2348                  */
2349                 ok_if_exists = 1;
2350         else
2351                 ok_if_exists = 0;
2352
2353         if (new_name &&
2354             ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2355                 if (check_index &&
2356                     cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2357                     !ok_if_exists)
2358                         return error("%s: already exists in index", new_name);
2359                 if (!cached) {
2360                         int err = check_to_create_blob(new_name, ok_if_exists);
2361                         if (err)
2362                                 return err;
2363                 }
2364                 if (!patch->new_mode) {
2365                         if (0 < patch->is_new)
2366                                 patch->new_mode = S_IFREG | 0644;
2367                         else
2368                                 patch->new_mode = patch->old_mode;
2369                 }
2370         }
2371
2372         if (new_name && old_name) {
2373                 int same = !strcmp(old_name, new_name);
2374                 if (!patch->new_mode)
2375                         patch->new_mode = patch->old_mode;
2376                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2377                         return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2378                                 patch->new_mode, new_name, patch->old_mode,
2379                                 same ? "" : " of ", same ? "" : old_name);
2380         }
2381
2382         if (apply_data(patch, &st, ce) < 0)
2383                 return error("%s: patch does not apply", name);
2384         patch->rejected = 0;
2385         return 0;
2386 }
2387
2388 static int check_patch_list(struct patch *patch)
2389 {
2390         struct patch *prev_patch = NULL;
2391         int err = 0;
2392
2393         for (prev_patch = NULL; patch ; patch = patch->next) {
2394                 if (apply_verbosely)
2395                         say_patch_name(stderr,
2396                                        "Checking patch ", patch, "...\n");
2397                 err |= check_patch(patch, prev_patch);
2398                 prev_patch = patch;
2399         }
2400         return err;
2401 }
2402
2403 /* This function tries to read the sha1 from the current index */
2404 static int get_current_sha1(const char *path, unsigned char *sha1)
2405 {
2406         int pos;
2407
2408         if (read_cache() < 0)
2409                 return -1;
2410         pos = cache_name_pos(path, strlen(path));
2411         if (pos < 0)
2412                 return -1;
2413         hashcpy(sha1, active_cache[pos]->sha1);
2414         return 0;
2415 }
2416
2417 /* Build an index that contains the just the files needed for a 3way merge */
2418 static void build_fake_ancestor(struct patch *list, const char *filename)
2419 {
2420         struct patch *patch;
2421         struct index_state result = { 0 };
2422         int fd;
2423
2424         /* Once we start supporting the reverse patch, it may be
2425          * worth showing the new sha1 prefix, but until then...
2426          */
2427         for (patch = list; patch; patch = patch->next) {
2428                 const unsigned char *sha1_ptr;
2429                 unsigned char sha1[20];
2430                 struct cache_entry *ce;
2431                 const char *name;
2432
2433                 name = patch->old_name ? patch->old_name : patch->new_name;
2434                 if (0 < patch->is_new)
2435                         continue;
2436                 else if (get_sha1(patch->old_sha1_prefix, sha1))
2437                         /* git diff has no index line for mode/type changes */
2438                         if (!patch->lines_added && !patch->lines_deleted) {
2439                                 if (get_current_sha1(patch->new_name, sha1) ||
2440                                     get_current_sha1(patch->old_name, sha1))
2441                                         die("mode change for %s, which is not "
2442                                                 "in current HEAD", name);
2443                                 sha1_ptr = sha1;
2444                         } else
2445                                 die("sha1 information is lacking or useless "
2446                                         "(%s).", name);
2447                 else
2448                         sha1_ptr = sha1;
2449
2450                 ce = make_cache_entry(patch->old_mode, sha1_ptr, name, 0, 0);
2451                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD))
2452                         die ("Could not add %s to temporary index", name);
2453         }
2454
2455         fd = open(filename, O_WRONLY | O_CREAT, 0666);
2456         if (fd < 0 || write_index(&result, fd) || close(fd))
2457                 die ("Could not write temporary index to %s", filename);
2458
2459         discard_index(&result);
2460 }
2461
2462 static void stat_patch_list(struct patch *patch)
2463 {
2464         int files, adds, dels;
2465
2466         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2467                 files++;
2468                 adds += patch->lines_added;
2469                 dels += patch->lines_deleted;
2470                 show_stats(patch);
2471         }
2472
2473         printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2474 }
2475
2476 static void numstat_patch_list(struct patch *patch)
2477 {
2478         for ( ; patch; patch = patch->next) {
2479                 const char *name;
2480                 name = patch->new_name ? patch->new_name : patch->old_name;
2481                 if (patch->is_binary)
2482                         printf("-\t-\t");
2483                 else
2484                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
2485                 write_name_quoted(name, stdout, line_termination);
2486         }
2487 }
2488
2489 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2490 {
2491         if (mode)
2492                 printf(" %s mode %06o %s\n", newdelete, mode, name);
2493         else
2494                 printf(" %s %s\n", newdelete, name);
2495 }
2496
2497 static void show_mode_change(struct patch *p, int show_name)
2498 {
2499         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2500                 if (show_name)
2501                         printf(" mode change %06o => %06o %s\n",
2502                                p->old_mode, p->new_mode, p->new_name);
2503                 else
2504                         printf(" mode change %06o => %06o\n",
2505                                p->old_mode, p->new_mode);
2506         }
2507 }
2508
2509 static void show_rename_copy(struct patch *p)
2510 {
2511         const char *renamecopy = p->is_rename ? "rename" : "copy";
2512         const char *old, *new;
2513
2514         /* Find common prefix */
2515         old = p->old_name;
2516         new = p->new_name;
2517         while (1) {
2518                 const char *slash_old, *slash_new;
2519                 slash_old = strchr(old, '/');
2520                 slash_new = strchr(new, '/');
2521                 if (!slash_old ||
2522                     !slash_new ||
2523                     slash_old - old != slash_new - new ||
2524                     memcmp(old, new, slash_new - new))
2525                         break;
2526                 old = slash_old + 1;
2527                 new = slash_new + 1;
2528         }
2529         /* p->old_name thru old is the common prefix, and old and new
2530          * through the end of names are renames
2531          */
2532         if (old != p->old_name)
2533                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2534                        (int)(old - p->old_name), p->old_name,
2535                        old, new, p->score);
2536         else
2537                 printf(" %s %s => %s (%d%%)\n", renamecopy,
2538                        p->old_name, p->new_name, p->score);
2539         show_mode_change(p, 0);
2540 }
2541
2542 static void summary_patch_list(struct patch *patch)
2543 {
2544         struct patch *p;
2545
2546         for (p = patch; p; p = p->next) {
2547                 if (p->is_new)
2548                         show_file_mode_name("create", p->new_mode, p->new_name);
2549                 else if (p->is_delete)
2550                         show_file_mode_name("delete", p->old_mode, p->old_name);
2551                 else {
2552                         if (p->is_rename || p->is_copy)
2553                                 show_rename_copy(p);
2554                         else {
2555                                 if (p->score) {
2556                                         printf(" rewrite %s (%d%%)\n",
2557                                                p->new_name, p->score);
2558                                         show_mode_change(p, 0);
2559                                 }
2560                                 else
2561                                         show_mode_change(p, 1);
2562                         }
2563                 }
2564         }
2565 }
2566
2567 static void patch_stats(struct patch *patch)
2568 {
2569         int lines = patch->lines_added + patch->lines_deleted;
2570
2571         if (lines > max_change)
2572                 max_change = lines;
2573         if (patch->old_name) {
2574                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2575                 if (!len)
2576                         len = strlen(patch->old_name);
2577                 if (len > max_len)
2578                         max_len = len;
2579         }
2580         if (patch->new_name) {
2581                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2582                 if (!len)
2583                         len = strlen(patch->new_name);
2584                 if (len > max_len)
2585                         max_len = len;
2586         }
2587 }
2588
2589 static void remove_file(struct patch *patch, int rmdir_empty)
2590 {
2591         if (update_index) {
2592                 if (remove_file_from_cache(patch->old_name) < 0)
2593                         die("unable to remove %s from index", patch->old_name);
2594         }
2595         if (!cached) {
2596                 if (S_ISGITLINK(patch->old_mode)) {
2597                         if (rmdir(patch->old_name))
2598                                 warning("unable to remove submodule %s",
2599                                         patch->old_name);
2600                 } else if (!unlink(patch->old_name) && rmdir_empty) {
2601                         char *name = xstrdup(patch->old_name);
2602                         char *end = strrchr(name, '/');
2603                         while (end) {
2604                                 *end = 0;
2605                                 if (rmdir(name))
2606                                         break;
2607                                 end = strrchr(name, '/');
2608                         }
2609                         free(name);
2610                 }
2611         }
2612 }
2613
2614 static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2615 {
2616         struct stat st;
2617         struct cache_entry *ce;
2618         int namelen = strlen(path);
2619         unsigned ce_size = cache_entry_size(namelen);
2620
2621         if (!update_index)
2622                 return;
2623
2624         ce = xcalloc(1, ce_size);
2625         memcpy(ce->name, path, namelen);
2626         ce->ce_mode = create_ce_mode(mode);
2627         ce->ce_flags = namelen;
2628         if (S_ISGITLINK(mode)) {
2629                 const char *s = buf;
2630
2631                 if (get_sha1_hex(s + strlen("Subproject commit "), ce->sha1))
2632                         die("corrupt patch for subproject %s", path);
2633         } else {
2634                 if (!cached) {
2635                         if (lstat(path, &st) < 0)
2636                                 die("unable to stat newly created file %s",
2637                                     path);
2638                         fill_stat_cache_info(ce, &st);
2639                 }
2640                 if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2641                         die("unable to create backing store for newly created file %s", path);
2642         }
2643         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2644                 die("unable to add cache entry for %s", path);
2645 }
2646
2647 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2648 {
2649         int fd;
2650         struct strbuf nbuf;
2651
2652         if (S_ISGITLINK(mode)) {
2653                 struct stat st;
2654                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
2655                         return 0;
2656                 return mkdir(path, 0777);
2657         }
2658
2659         if (has_symlinks && S_ISLNK(mode))
2660                 /* Although buf:size is counted string, it also is NUL
2661                  * terminated.
2662                  */
2663                 return symlink(buf, path);
2664
2665         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2666         if (fd < 0)
2667                 return -1;
2668
2669         strbuf_init(&nbuf, 0);
2670         if (convert_to_working_tree(path, buf, size, &nbuf)) {
2671                 size = nbuf.len;
2672                 buf  = nbuf.buf;
2673         }
2674         write_or_die(fd, buf, size);
2675         strbuf_release(&nbuf);
2676
2677         if (close(fd) < 0)
2678                 die("closing file %s: %s", path, strerror(errno));
2679         return 0;
2680 }
2681
2682 /*
2683  * We optimistically assume that the directories exist,
2684  * which is true 99% of the time anyway. If they don't,
2685  * we create them and try again.
2686  */
2687 static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2688 {
2689         if (cached)
2690                 return;
2691         if (!try_create_file(path, mode, buf, size))
2692                 return;
2693
2694         if (errno == ENOENT) {
2695                 if (safe_create_leading_directories(path))
2696                         return;
2697                 if (!try_create_file(path, mode, buf, size))
2698                         return;
2699         }
2700
2701         if (errno == EEXIST || errno == EACCES) {
2702                 /* We may be trying to create a file where a directory
2703                  * used to be.
2704                  */
2705                 struct stat st;
2706                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
2707                         errno = EEXIST;
2708         }
2709
2710         if (errno == EEXIST) {
2711                 unsigned int nr = getpid();
2712
2713                 for (;;) {
2714                         const char *newpath;
2715                         newpath = mkpath("%s~%u", path, nr);
2716                         if (!try_create_file(newpath, mode, buf, size)) {
2717                                 if (!rename(newpath, path))
2718                                         return;
2719                                 unlink(newpath);
2720                                 break;
2721                         }
2722                         if (errno != EEXIST)
2723                                 break;
2724                         ++nr;
2725                 }
2726         }
2727         die("unable to write file %s mode %o", path, mode);
2728 }
2729
2730 static void create_file(struct patch *patch)
2731 {
2732         char *path = patch->new_name;
2733         unsigned mode = patch->new_mode;
2734         unsigned long size = patch->resultsize;
2735         char *buf = patch->result;
2736
2737         if (!mode)
2738                 mode = S_IFREG | 0644;
2739         create_one_file(path, mode, buf, size);
2740         add_index_file(path, mode, buf, size);
2741 }
2742
2743 /* phase zero is to remove, phase one is to create */
2744 static void write_out_one_result(struct patch *patch, int phase)
2745 {
2746         if (patch->is_delete > 0) {
2747                 if (phase == 0)
2748                         remove_file(patch, 1);
2749                 return;
2750         }
2751         if (patch->is_new > 0 || patch->is_copy) {
2752                 if (phase == 1)
2753                         create_file(patch);
2754                 return;
2755         }
2756         /*
2757          * Rename or modification boils down to the same
2758          * thing: remove the old, write the new
2759          */
2760         if (phase == 0)
2761                 remove_file(patch, patch->is_rename);
2762         if (phase == 1)
2763                 create_file(patch);
2764 }
2765
2766 static int write_out_one_reject(struct patch *patch)
2767 {
2768         FILE *rej;
2769         char namebuf[PATH_MAX];
2770         struct fragment *frag;
2771         int cnt = 0;
2772
2773         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2774                 if (!frag->rejected)
2775                         continue;
2776                 cnt++;
2777         }
2778
2779         if (!cnt) {
2780                 if (apply_verbosely)
2781                         say_patch_name(stderr,
2782                                        "Applied patch ", patch, " cleanly.\n");
2783                 return 0;
2784         }
2785
2786         /* This should not happen, because a removal patch that leaves
2787          * contents are marked "rejected" at the patch level.
2788          */
2789         if (!patch->new_name)
2790                 die("internal error");
2791
2792         /* Say this even without --verbose */
2793         say_patch_name(stderr, "Applying patch ", patch, " with");
2794         fprintf(stderr, " %d rejects...\n", cnt);
2795
2796         cnt = strlen(patch->new_name);
2797         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2798                 cnt = ARRAY_SIZE(namebuf) - 5;
2799                 fprintf(stderr,
2800                         "warning: truncating .rej filename to %.*s.rej",
2801                         cnt - 1, patch->new_name);
2802         }
2803         memcpy(namebuf, patch->new_name, cnt);
2804         memcpy(namebuf + cnt, ".rej", 5);
2805
2806         rej = fopen(namebuf, "w");
2807         if (!rej)
2808                 return error("cannot open %s: %s", namebuf, strerror(errno));
2809
2810         /* Normal git tools never deal with .rej, so do not pretend
2811          * this is a git patch by saying --git nor give extended
2812          * headers.  While at it, maybe please "kompare" that wants
2813          * the trailing TAB and some garbage at the end of line ;-).
2814          */
2815         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2816                 patch->new_name, patch->new_name);
2817         for (cnt = 1, frag = patch->fragments;
2818              frag;
2819              cnt++, frag = frag->next) {
2820                 if (!frag->rejected) {
2821                         fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2822                         continue;
2823                 }
2824                 fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2825                 fprintf(rej, "%.*s", frag->size, frag->patch);
2826                 if (frag->patch[frag->size-1] != '\n')
2827                         fputc('\n', rej);
2828         }
2829         fclose(rej);
2830         return -1;
2831 }
2832
2833 static int write_out_results(struct patch *list, int skipped_patch)
2834 {
2835         int phase;
2836         int errs = 0;
2837         struct patch *l;
2838
2839         if (!list && !skipped_patch)
2840                 return error("No changes");
2841
2842         for (phase = 0; phase < 2; phase++) {
2843                 l = list;
2844                 while (l) {
2845                         if (l->rejected)
2846                                 errs = 1;
2847                         else {
2848                                 write_out_one_result(l, phase);
2849                                 if (phase == 1 && write_out_one_reject(l))
2850                                         errs = 1;
2851                         }
2852                         l = l->next;
2853                 }
2854         }
2855         return errs;
2856 }
2857
2858 static struct lock_file lock_file;
2859
2860 static struct excludes {
2861         struct excludes *next;
2862         const char *path;
2863 } *excludes;
2864
2865 static int use_patch(struct patch *p)
2866 {
2867         const char *pathname = p->new_name ? p->new_name : p->old_name;
2868         struct excludes *x = excludes;
2869         while (x) {
2870                 if (fnmatch(x->path, pathname, 0) == 0)
2871                         return 0;
2872                 x = x->next;
2873         }
2874         if (0 < prefix_length) {
2875                 int pathlen = strlen(pathname);
2876                 if (pathlen <= prefix_length ||
2877                     memcmp(prefix, pathname, prefix_length))
2878                         return 0;
2879         }
2880         return 1;
2881 }
2882
2883 static void prefix_one(char **name)
2884 {
2885         char *old_name = *name;
2886         if (!old_name)
2887                 return;
2888         *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
2889         free(old_name);
2890 }
2891
2892 static void prefix_patches(struct patch *p)
2893 {
2894         if (!prefix || p->is_toplevel_relative)
2895                 return;
2896         for ( ; p; p = p->next) {
2897                 if (p->new_name == p->old_name) {
2898                         char *prefixed = p->new_name;
2899                         prefix_one(&prefixed);
2900                         p->new_name = p->old_name = prefixed;
2901                 }
2902                 else {
2903                         prefix_one(&p->new_name);
2904                         prefix_one(&p->old_name);
2905                 }
2906         }
2907 }
2908
2909 static int apply_patch(int fd, const char *filename, int inaccurate_eof)
2910 {
2911         size_t offset;
2912         struct strbuf buf;
2913         struct patch *list = NULL, **listp = &list;
2914         int skipped_patch = 0;
2915
2916         strbuf_init(&buf, 0);
2917         patch_input_file = filename;
2918         read_patch_file(&buf, fd);
2919         offset = 0;
2920         while (offset < buf.len) {
2921                 struct patch *patch;
2922                 int nr;
2923
2924                 patch = xcalloc(1, sizeof(*patch));
2925                 patch->inaccurate_eof = inaccurate_eof;
2926                 nr = parse_chunk(buf.buf + offset, buf.len - offset, patch);
2927                 if (nr < 0)
2928                         break;
2929                 if (apply_in_reverse)
2930                         reverse_patches(patch);
2931                 if (prefix)
2932                         prefix_patches(patch);
2933                 if (use_patch(patch)) {
2934                         patch_stats(patch);
2935                         *listp = patch;
2936                         listp = &patch->next;
2937                 }
2938                 else {
2939                         /* perhaps free it a bit better? */
2940                         free(patch);
2941                         skipped_patch++;
2942                 }
2943                 offset += nr;
2944         }
2945
2946         if (whitespace_error && (ws_error_action == die_on_ws_error))
2947                 apply = 0;
2948
2949         update_index = check_index && apply;
2950         if (update_index && newfd < 0)
2951                 newfd = hold_locked_index(&lock_file, 1);
2952
2953         if (check_index) {
2954                 if (read_cache() < 0)
2955                         die("unable to read index file");
2956         }
2957
2958         if ((check || apply) &&
2959             check_patch_list(list) < 0 &&
2960             !apply_with_reject)
2961                 exit(1);
2962
2963         if (apply && write_out_results(list, skipped_patch))
2964                 exit(1);
2965
2966         if (fake_ancestor)
2967                 build_fake_ancestor(list, fake_ancestor);
2968
2969         if (diffstat)
2970                 stat_patch_list(list);
2971
2972         if (numstat)
2973                 numstat_patch_list(list);
2974
2975         if (summary)
2976                 summary_patch_list(list);
2977
2978         strbuf_release(&buf);
2979         return 0;
2980 }
2981
2982 static int git_apply_config(const char *var, const char *value)
2983 {
2984         if (!strcmp(var, "apply.whitespace")) {
2985                 if (!value)
2986                         return config_error_nonbool(var);
2987                 apply_default_whitespace = xstrdup(value);
2988                 return 0;
2989         }
2990         return git_default_config(var, value);
2991 }
2992
2993
2994 int cmd_apply(int argc, const char **argv, const char *unused_prefix)
2995 {
2996         int i;
2997         int read_stdin = 1;
2998         int inaccurate_eof = 0;
2999         int errs = 0;
3000         int is_not_gitdir;
3001
3002         const char *whitespace_option = NULL;
3003
3004         prefix = setup_git_directory_gently(&is_not_gitdir);
3005         prefix_length = prefix ? strlen(prefix) : 0;
3006         git_config(git_apply_config);
3007         if (apply_default_whitespace)
3008                 parse_whitespace_option(apply_default_whitespace);
3009
3010         for (i = 1; i < argc; i++) {
3011                 const char *arg = argv[i];
3012                 char *end;
3013                 int fd;
3014
3015                 if (!strcmp(arg, "-")) {
3016                         errs |= apply_patch(0, "<stdin>", inaccurate_eof);
3017                         read_stdin = 0;
3018                         continue;
3019                 }
3020                 if (!prefixcmp(arg, "--exclude=")) {
3021                         struct excludes *x = xmalloc(sizeof(*x));
3022                         x->path = arg + 10;
3023                         x->next = excludes;
3024                         excludes = x;
3025                         continue;
3026                 }
3027                 if (!prefixcmp(arg, "-p")) {
3028                         p_value = atoi(arg + 2);
3029                         p_value_known = 1;
3030                         continue;
3031                 }
3032                 if (!strcmp(arg, "--no-add")) {
3033                         no_add = 1;
3034                         continue;
3035                 }
3036                 if (!strcmp(arg, "--stat")) {
3037                         apply = 0;
3038                         diffstat = 1;
3039                         continue;
3040                 }
3041                 if (!strcmp(arg, "--allow-binary-replacement") ||
3042                     !strcmp(arg, "--binary")) {
3043                         continue; /* now no-op */
3044                 }
3045                 if (!strcmp(arg, "--numstat")) {
3046                         apply = 0;
3047                         numstat = 1;
3048                         continue;
3049                 }
3050                 if (!strcmp(arg, "--summary")) {
3051                         apply = 0;
3052                         summary = 1;
3053                         continue;
3054                 }
3055                 if (!strcmp(arg, "--check")) {
3056                         apply = 0;
3057                         check = 1;
3058                         continue;
3059                 }
3060                 if (!strcmp(arg, "--index")) {
3061                         if (is_not_gitdir)
3062                                 die("--index outside a repository");
3063                         check_index = 1;
3064                         continue;
3065                 }
3066                 if (!strcmp(arg, "--cached")) {
3067                         if (is_not_gitdir)
3068                                 die("--cached outside a repository");
3069                         check_index = 1;
3070                         cached = 1;
3071                         continue;
3072                 }
3073                 if (!strcmp(arg, "--apply")) {
3074                         apply = 1;
3075                         continue;
3076                 }
3077                 if (!strcmp(arg, "--build-fake-ancestor")) {
3078                         apply = 0;
3079                         if (++i >= argc)
3080                                 die ("need a filename");
3081                         fake_ancestor = argv[i];
3082                         continue;
3083                 }
3084                 if (!strcmp(arg, "-z")) {
3085                         line_termination = 0;
3086                         continue;
3087                 }
3088                 if (!prefixcmp(arg, "-C")) {
3089                         p_context = strtoul(arg + 2, &end, 0);
3090                         if (*end != '\0')
3091                                 die("unrecognized context count '%s'", arg + 2);
3092                         continue;
3093                 }
3094                 if (!prefixcmp(arg, "--whitespace=")) {
3095                         whitespace_option = arg + 13;
3096                         parse_whitespace_option(arg + 13);
3097                         continue;
3098                 }
3099                 if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
3100                         apply_in_reverse = 1;
3101                         continue;
3102                 }
3103                 if (!strcmp(arg, "--unidiff-zero")) {
3104                         unidiff_zero = 1;
3105                         continue;
3106                 }
3107                 if (!strcmp(arg, "--reject")) {
3108                         apply = apply_with_reject = apply_verbosely = 1;
3109                         continue;
3110                 }
3111                 if (!strcmp(arg, "-v") || !strcmp(arg, "--verbose")) {
3112                         apply_verbosely = 1;
3113                         continue;
3114                 }
3115                 if (!strcmp(arg, "--inaccurate-eof")) {
3116                         inaccurate_eof = 1;
3117                         continue;
3118                 }
3119                 if (0 < prefix_length)
3120                         arg = prefix_filename(prefix, prefix_length, arg);
3121
3122                 fd = open(arg, O_RDONLY);
3123                 if (fd < 0)
3124                         die("can't open patch '%s': %s", arg, strerror(errno));
3125                 read_stdin = 0;
3126                 set_default_whitespace_mode(whitespace_option);
3127                 errs |= apply_patch(fd, arg, inaccurate_eof);
3128                 close(fd);
3129         }
3130         set_default_whitespace_mode(whitespace_option);
3131         if (read_stdin)
3132                 errs |= apply_patch(0, "<stdin>", inaccurate_eof);
3133         if (whitespace_error) {
3134                 if (squelch_whitespace_errors &&
3135                     squelch_whitespace_errors < whitespace_error) {
3136                         int squelched =
3137                                 whitespace_error - squelch_whitespace_errors;
3138                         fprintf(stderr, "warning: squelched %d "
3139                                 "whitespace error%s\n",
3140                                 squelched,
3141                                 squelched == 1 ? "" : "s");
3142                 }
3143                 if (ws_error_action == die_on_ws_error)
3144                         die("%d line%s add%s whitespace errors.",
3145                             whitespace_error,
3146                             whitespace_error == 1 ? "" : "s",
3147                             whitespace_error == 1 ? "s" : "");
3148                 if (applied_after_fixing_ws && apply)
3149                         fprintf(stderr, "warning: %d line%s applied after"
3150                                 " fixing whitespace errors.\n",
3151                                 applied_after_fixing_ws,
3152                                 applied_after_fixing_ws == 1 ? "" : "s");
3153                 else if (whitespace_error)
3154                         fprintf(stderr, "warning: %d line%s add%s whitespace errors.\n",
3155                                 whitespace_error,
3156                                 whitespace_error == 1 ? "" : "s",
3157                                 whitespace_error == 1 ? "s" : "");
3158         }
3159
3160         if (update_index) {
3161                 if (write_cache(newfd, active_cache, active_nr) ||
3162                     commit_locked_index(&lock_file))
3163                         die("Unable to write new index file");
3164         }
3165
3166         return !!errs;
3167 }