38f647510a13f51e63a35aaf442aeb154e34915c
   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 */
  25static const char *prefix;
  26static int prefix_length = -1;
  27static int newfd = -1;
  28
  29static int unidiff_zero;
  30static int p_value = 1;
  31static int p_value_known;
  32static int check_index;
  33static int write_index;
  34static int cached;
  35static int diffstat;
  36static int numstat;
  37static int summary;
  38static int check;
  39static int apply = 1;
  40static int apply_in_reverse;
  41static int apply_with_reject;
  42static int apply_verbosely;
  43static int no_add;
  44static int show_index_info;
  45static int line_termination = '\n';
  46static unsigned long p_context = ULONG_MAX;
  47static const char apply_usage[] =
  48"git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [--reverse] [--reject] [--verbose] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|error|error-all|strip>] <patch>...";
  49
  50static enum whitespace_eol {
  51        nowarn_whitespace,
  52        warn_on_whitespace,
  53        error_on_whitespace,
  54        strip_whitespace,
  55} new_whitespace = warn_on_whitespace;
  56static int whitespace_error;
  57static int squelch_whitespace_errors = 5;
  58static int applied_after_stripping;
  59static const char *patch_input_file;
  60
  61static void parse_whitespace_option(const char *option)
  62{
  63        if (!option) {
  64                new_whitespace = warn_on_whitespace;
  65                return;
  66        }
  67        if (!strcmp(option, "warn")) {
  68                new_whitespace = warn_on_whitespace;
  69                return;
  70        }
  71        if (!strcmp(option, "nowarn")) {
  72                new_whitespace = nowarn_whitespace;
  73                return;
  74        }
  75        if (!strcmp(option, "error")) {
  76                new_whitespace = error_on_whitespace;
  77                return;
  78        }
  79        if (!strcmp(option, "error-all")) {
  80                new_whitespace = error_on_whitespace;
  81                squelch_whitespace_errors = 0;
  82                return;
  83        }
  84        if (!strcmp(option, "strip")) {
  85                new_whitespace = strip_whitespace;
  86                return;
  87        }
  88        die("unrecognized whitespace option '%s'", option);
  89}
  90
  91static void set_default_whitespace_mode(const char *whitespace_option)
  92{
  93        if (!whitespace_option && !apply_default_whitespace) {
  94                new_whitespace = (apply
  95                                  ? warn_on_whitespace
  96                                  : nowarn_whitespace);
  97        }
  98}
  99
 100/*
 101 * For "diff-stat" like behaviour, we keep track of the biggest change
 102 * we've seen, and the longest filename. That allows us to do simple
 103 * scaling.
 104 */
 105static int max_change, max_len;
 106
 107/*
 108 * Various "current state", notably line numbers and what
 109 * file (and how) we're patching right now.. The "is_xxxx"
 110 * things are flags, where -1 means "don't know yet".
 111 */
 112static int linenr = 1;
 113
 114/*
 115 * This represents one "hunk" from a patch, starting with
 116 * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 117 * patch text is pointed at by patch, and its byte length
 118 * is stored in size.  leading and trailing are the number
 119 * of context lines.
 120 */
 121struct fragment {
 122        unsigned long leading, trailing;
 123        unsigned long oldpos, oldlines;
 124        unsigned long newpos, newlines;
 125        const char *patch;
 126        int size;
 127        int rejected;
 128        struct fragment *next;
 129};
 130
 131/*
 132 * When dealing with a binary patch, we reuse "leading" field
 133 * to store the type of the binary hunk, either deflated "delta"
 134 * or deflated "literal".
 135 */
 136#define binary_patch_method leading
 137#define BINARY_DELTA_DEFLATED   1
 138#define BINARY_LITERAL_DEFLATED 2
 139
 140struct patch {
 141        char *new_name, *old_name, *def_name;
 142        unsigned int old_mode, new_mode;
 143        int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
 144        int rejected;
 145        unsigned long deflate_origlen;
 146        int lines_added, lines_deleted;
 147        int score;
 148        unsigned int is_toplevel_relative:1;
 149        unsigned int inaccurate_eof:1;
 150        unsigned int is_binary:1;
 151        unsigned int is_copy:1;
 152        unsigned int is_rename:1;
 153        struct fragment *fragments;
 154        char *result;
 155        unsigned long resultsize;
 156        char old_sha1_prefix[41];
 157        char new_sha1_prefix[41];
 158        struct patch *next;
 159};
 160
 161static void say_patch_name(FILE *output, const char *pre, struct patch *patch, const char *post)
 162{
 163        fputs(pre, output);
 164        if (patch->old_name && patch->new_name &&
 165            strcmp(patch->old_name, patch->new_name)) {
 166                write_name_quoted(NULL, 0, patch->old_name, 1, output);
 167                fputs(" => ", output);
 168                write_name_quoted(NULL, 0, patch->new_name, 1, output);
 169        }
 170        else {
 171                const char *n = patch->new_name;
 172                if (!n)
 173                        n = patch->old_name;
 174                write_name_quoted(NULL, 0, n, 1, output);
 175        }
 176        fputs(post, output);
 177}
 178
 179#define CHUNKSIZE (8192)
 180#define SLOP (16)
 181
 182static void *read_patch_file(int fd, unsigned long *sizep)
 183{
 184        unsigned long size = 0, alloc = CHUNKSIZE;
 185        void *buffer = xmalloc(alloc);
 186
 187        for (;;) {
 188                int nr = alloc - size;
 189                if (nr < 1024) {
 190                        alloc += CHUNKSIZE;
 191                        buffer = xrealloc(buffer, alloc);
 192                        nr = alloc - size;
 193                }
 194                nr = xread(fd, (char *) buffer + size, nr);
 195                if (!nr)
 196                        break;
 197                if (nr < 0)
 198                        die("git-apply: read returned %s", strerror(errno));
 199                size += nr;
 200        }
 201        *sizep = size;
 202
 203        /*
 204         * Make sure that we have some slop in the buffer
 205         * so that we can do speculative "memcmp" etc, and
 206         * see to it that it is NUL-filled.
 207         */
 208        if (alloc < size + SLOP)
 209                buffer = xrealloc(buffer, size + SLOP);
 210        memset((char *) buffer + size, 0, SLOP);
 211        return buffer;
 212}
 213
 214static unsigned long linelen(const char *buffer, unsigned long size)
 215{
 216        unsigned long len = 0;
 217        while (size--) {
 218                len++;
 219                if (*buffer++ == '\n')
 220                        break;
 221        }
 222        return len;
 223}
 224
 225static int is_dev_null(const char *str)
 226{
 227        return !memcmp("/dev/null", str, 9) && isspace(str[9]);
 228}
 229
 230#define TERM_SPACE      1
 231#define TERM_TAB        2
 232
 233static int name_terminate(const char *name, int namelen, int c, int terminate)
 234{
 235        if (c == ' ' && !(terminate & TERM_SPACE))
 236                return 0;
 237        if (c == '\t' && !(terminate & TERM_TAB))
 238                return 0;
 239
 240        return 1;
 241}
 242
 243static char *find_name(const char *line, char *def, int p_value, int terminate)
 244{
 245        int len;
 246        const char *start = line;
 247        char *name;
 248
 249        if (*line == '"') {
 250                /* Proposed "new-style" GNU patch/diff format; see
 251                 * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
 252                 */
 253                name = unquote_c_style(line, NULL);
 254                if (name) {
 255                        char *cp = name;
 256                        while (p_value) {
 257                                cp = strchr(name, '/');
 258                                if (!cp)
 259                                        break;
 260                                cp++;
 261                                p_value--;
 262                        }
 263                        if (cp) {
 264                                /* name can later be freed, so we need
 265                                 * to memmove, not just return cp
 266                                 */
 267                                memmove(name, cp, strlen(cp) + 1);
 268                                free(def);
 269                                return name;
 270                        }
 271                        else {
 272                                free(name);
 273                                name = NULL;
 274                        }
 275                }
 276        }
 277
 278        for (;;) {
 279                char c = *line;
 280
 281                if (isspace(c)) {
 282                        if (c == '\n')
 283                                break;
 284                        if (name_terminate(start, line-start, c, terminate))
 285                                break;
 286                }
 287                line++;
 288                if (c == '/' && !--p_value)
 289                        start = line;
 290        }
 291        if (!start)
 292                return def;
 293        len = line - start;
 294        if (!len)
 295                return def;
 296
 297        /*
 298         * Generally we prefer the shorter name, especially
 299         * if the other one is just a variation of that with
 300         * something else tacked on to the end (ie "file.orig"
 301         * or "file~").
 302         */
 303        if (def) {
 304                int deflen = strlen(def);
 305                if (deflen < len && !strncmp(start, def, deflen))
 306                        return def;
 307        }
 308
 309        name = xmalloc(len + 1);
 310        memcpy(name, start, len);
 311        name[len] = 0;
 312        free(def);
 313        return name;
 314}
 315
 316static int count_slashes(const char *cp)
 317{
 318        int cnt = 0;
 319        char ch;
 320
 321        while ((ch = *cp++))
 322                if (ch == '/')
 323                        cnt++;
 324        return cnt;
 325}
 326
 327/*
 328 * Given the string after "--- " or "+++ ", guess the appropriate
 329 * p_value for the given patch.
 330 */
 331static int guess_p_value(const char *nameline)
 332{
 333        char *name, *cp;
 334        int val = -1;
 335
 336        if (is_dev_null(nameline))
 337                return -1;
 338        name = find_name(nameline, NULL, 0, TERM_SPACE | TERM_TAB);
 339        if (!name)
 340                return -1;
 341        cp = strchr(name, '/');
 342        if (!cp)
 343                val = 0;
 344        else if (prefix) {
 345                /*
 346                 * Does it begin with "a/$our-prefix" and such?  Then this is
 347                 * very likely to apply to our directory.
 348                 */
 349                if (!strncmp(name, prefix, prefix_length))
 350                        val = count_slashes(prefix);
 351                else {
 352                        cp++;
 353                        if (!strncmp(cp, prefix, prefix_length))
 354                                val = count_slashes(prefix) + 1;
 355                }
 356        }
 357        free(name);
 358        return val;
 359}
 360
 361/*
 362 * Get the name etc info from the --/+++ lines of a traditional patch header
 363 *
 364 * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 365 * files, we can happily check the index for a match, but for creating a
 366 * new file we should try to match whatever "patch" does. I have no idea.
 367 */
 368static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
 369{
 370        char *name;
 371
 372        first += 4;     /* skip "--- " */
 373        second += 4;    /* skip "+++ " */
 374        if (!p_value_known) {
 375                int p, q;
 376                p = guess_p_value(first);
 377                q = guess_p_value(second);
 378                if (p < 0) p = q;
 379                if (0 <= p && p == q) {
 380                        p_value = p;
 381                        p_value_known = 1;
 382                }
 383        }
 384        if (is_dev_null(first)) {
 385                patch->is_new = 1;
 386                patch->is_delete = 0;
 387                name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
 388                patch->new_name = name;
 389        } else if (is_dev_null(second)) {
 390                patch->is_new = 0;
 391                patch->is_delete = 1;
 392                name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 393                patch->old_name = name;
 394        } else {
 395                name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
 396                name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
 397                patch->old_name = patch->new_name = name;
 398        }
 399        if (!name)
 400                die("unable to find filename in patch at line %d", linenr);
 401}
 402
 403static int gitdiff_hdrend(const char *line, struct patch *patch)
 404{
 405        return -1;
 406}
 407
 408/*
 409 * We're anal about diff header consistency, to make
 410 * sure that we don't end up having strange ambiguous
 411 * patches floating around.
 412 *
 413 * As a result, gitdiff_{old|new}name() will check
 414 * their names against any previous information, just
 415 * to make sure..
 416 */
 417static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
 418{
 419        if (!orig_name && !isnull)
 420                return find_name(line, NULL, 1, TERM_TAB);
 421
 422        if (orig_name) {
 423                int len;
 424                const char *name;
 425                char *another;
 426                name = orig_name;
 427                len = strlen(name);
 428                if (isnull)
 429                        die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
 430                another = find_name(line, NULL, 1, TERM_TAB);
 431                if (!another || memcmp(another, name, len))
 432                        die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
 433                free(another);
 434                return orig_name;
 435        }
 436        else {
 437                /* expect "/dev/null" */
 438                if (memcmp("/dev/null", line, 9) || line[9] != '\n')
 439                        die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
 440                return NULL;
 441        }
 442}
 443
 444static int gitdiff_oldname(const char *line, struct patch *patch)
 445{
 446        patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
 447        return 0;
 448}
 449
 450static int gitdiff_newname(const char *line, struct patch *patch)
 451{
 452        patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
 453        return 0;
 454}
 455
 456static int gitdiff_oldmode(const char *line, struct patch *patch)
 457{
 458        patch->old_mode = strtoul(line, NULL, 8);
 459        return 0;
 460}
 461
 462static int gitdiff_newmode(const char *line, struct patch *patch)
 463{
 464        patch->new_mode = strtoul(line, NULL, 8);
 465        return 0;
 466}
 467
 468static int gitdiff_delete(const char *line, struct patch *patch)
 469{
 470        patch->is_delete = 1;
 471        patch->old_name = patch->def_name;
 472        return gitdiff_oldmode(line, patch);
 473}
 474
 475static int gitdiff_newfile(const char *line, struct patch *patch)
 476{
 477        patch->is_new = 1;
 478        patch->new_name = patch->def_name;
 479        return gitdiff_newmode(line, patch);
 480}
 481
 482static int gitdiff_copysrc(const char *line, struct patch *patch)
 483{
 484        patch->is_copy = 1;
 485        patch->old_name = find_name(line, NULL, 0, 0);
 486        return 0;
 487}
 488
 489static int gitdiff_copydst(const char *line, struct patch *patch)
 490{
 491        patch->is_copy = 1;
 492        patch->new_name = find_name(line, NULL, 0, 0);
 493        return 0;
 494}
 495
 496static int gitdiff_renamesrc(const char *line, struct patch *patch)
 497{
 498        patch->is_rename = 1;
 499        patch->old_name = find_name(line, NULL, 0, 0);
 500        return 0;
 501}
 502
 503static int gitdiff_renamedst(const char *line, struct patch *patch)
 504{
 505        patch->is_rename = 1;
 506        patch->new_name = find_name(line, NULL, 0, 0);
 507        return 0;
 508}
 509
 510static int gitdiff_similarity(const char *line, struct patch *patch)
 511{
 512        if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 513                patch->score = 0;
 514        return 0;
 515}
 516
 517static int gitdiff_dissimilarity(const char *line, struct patch *patch)
 518{
 519        if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
 520                patch->score = 0;
 521        return 0;
 522}
 523
 524static int gitdiff_index(const char *line, struct patch *patch)
 525{
 526        /* index line is N hexadecimal, "..", N hexadecimal,
 527         * and optional space with octal mode.
 528         */
 529        const char *ptr, *eol;
 530        int len;
 531
 532        ptr = strchr(line, '.');
 533        if (!ptr || ptr[1] != '.' || 40 < ptr - line)
 534                return 0;
 535        len = ptr - line;
 536        memcpy(patch->old_sha1_prefix, line, len);
 537        patch->old_sha1_prefix[len] = 0;
 538
 539        line = ptr + 2;
 540        ptr = strchr(line, ' ');
 541        eol = strchr(line, '\n');
 542
 543        if (!ptr || eol < ptr)
 544                ptr = eol;
 545        len = ptr - line;
 546
 547        if (40 < len)
 548                return 0;
 549        memcpy(patch->new_sha1_prefix, line, len);
 550        patch->new_sha1_prefix[len] = 0;
 551        if (*ptr == ' ')
 552                patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
 553        return 0;
 554}
 555
 556/*
 557 * This is normal for a diff that doesn't change anything: we'll fall through
 558 * into the next diff. Tell the parser to break out.
 559 */
 560static int gitdiff_unrecognized(const char *line, struct patch *patch)
 561{
 562        return -1;
 563}
 564
 565static const char *stop_at_slash(const char *line, int llen)
 566{
 567        int i;
 568
 569        for (i = 0; i < llen; i++) {
 570                int ch = line[i];
 571                if (ch == '/')
 572                        return line + i;
 573        }
 574        return NULL;
 575}
 576
 577/* This is to extract the same name that appears on "diff --git"
 578 * line.  We do not find and return anything if it is a rename
 579 * patch, and it is OK because we will find the name elsewhere.
 580 * We need to reliably find name only when it is mode-change only,
 581 * creation or deletion of an empty file.  In any of these cases,
 582 * both sides are the same name under a/ and b/ respectively.
 583 */
 584static char *git_header_name(char *line, int llen)
 585{
 586        int len;
 587        const char *name;
 588        const char *second = NULL;
 589
 590        line += strlen("diff --git ");
 591        llen -= strlen("diff --git ");
 592
 593        if (*line == '"') {
 594                const char *cp;
 595                char *first = unquote_c_style(line, &second);
 596                if (!first)
 597                        return NULL;
 598
 599                /* advance to the first slash */
 600                cp = stop_at_slash(first, strlen(first));
 601                if (!cp || cp == first) {
 602                        /* we do not accept absolute paths */
 603                free_first_and_fail:
 604                        free(first);
 605                        return NULL;
 606                }
 607                len = strlen(cp+1);
 608                memmove(first, cp+1, len+1); /* including NUL */
 609
 610                /* second points at one past closing dq of name.
 611                 * find the second name.
 612                 */
 613                while ((second < line + llen) && isspace(*second))
 614                        second++;
 615
 616                if (line + llen <= second)
 617                        goto free_first_and_fail;
 618                if (*second == '"') {
 619                        char *sp = unquote_c_style(second, NULL);
 620                        if (!sp)
 621                                goto free_first_and_fail;
 622                        cp = stop_at_slash(sp, strlen(sp));
 623                        if (!cp || cp == sp) {
 624                        free_both_and_fail:
 625                                free(sp);
 626                                goto free_first_and_fail;
 627                        }
 628                        /* They must match, otherwise ignore */
 629                        if (strcmp(cp+1, first))
 630                                goto free_both_and_fail;
 631                        free(sp);
 632                        return first;
 633                }
 634
 635                /* unquoted second */
 636                cp = stop_at_slash(second, line + llen - second);
 637                if (!cp || cp == second)
 638                        goto free_first_and_fail;
 639                cp++;
 640                if (line + llen - cp != len + 1 ||
 641                    memcmp(first, cp, len))
 642                        goto free_first_and_fail;
 643                return first;
 644        }
 645
 646        /* unquoted first name */
 647        name = stop_at_slash(line, llen);
 648        if (!name || name == line)
 649                return NULL;
 650
 651        name++;
 652
 653        /* since the first name is unquoted, a dq if exists must be
 654         * the beginning of the second name.
 655         */
 656        for (second = name; second < line + llen; second++) {
 657                if (*second == '"') {
 658                        const char *cp = second;
 659                        const char *np;
 660                        char *sp = unquote_c_style(second, NULL);
 661
 662                        if (!sp)
 663                                return NULL;
 664                        np = stop_at_slash(sp, strlen(sp));
 665                        if (!np || np == sp) {
 666                        free_second_and_fail:
 667                                free(sp);
 668                                return NULL;
 669                        }
 670                        np++;
 671                        len = strlen(np);
 672                        if (len < cp - name &&
 673                            !strncmp(np, name, len) &&
 674                            isspace(name[len])) {
 675                                /* Good */
 676                                memmove(sp, np, len + 1);
 677                                return sp;
 678                        }
 679                        goto free_second_and_fail;
 680                }
 681        }
 682
 683        /*
 684         * Accept a name only if it shows up twice, exactly the same
 685         * form.
 686         */
 687        for (len = 0 ; ; len++) {
 688                switch (name[len]) {
 689                default:
 690                        continue;
 691                case '\n':
 692                        return NULL;
 693                case '\t': case ' ':
 694                        second = name+len;
 695                        for (;;) {
 696                                char c = *second++;
 697                                if (c == '\n')
 698                                        return NULL;
 699                                if (c == '/')
 700                                        break;
 701                        }
 702                        if (second[len] == '\n' && !memcmp(name, second, len)) {
 703                                char *ret = xmalloc(len + 1);
 704                                memcpy(ret, name, len);
 705                                ret[len] = 0;
 706                                return ret;
 707                        }
 708                }
 709        }
 710        return NULL;
 711}
 712
 713/* Verify that we recognize the lines following a git header */
 714static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
 715{
 716        unsigned long offset;
 717
 718        /* A git diff has explicit new/delete information, so we don't guess */
 719        patch->is_new = 0;
 720        patch->is_delete = 0;
 721
 722        /*
 723         * Some things may not have the old name in the
 724         * rest of the headers anywhere (pure mode changes,
 725         * or removing or adding empty files), so we get
 726         * the default name from the header.
 727         */
 728        patch->def_name = git_header_name(line, len);
 729
 730        line += len;
 731        size -= len;
 732        linenr++;
 733        for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
 734                static const struct opentry {
 735                        const char *str;
 736                        int (*fn)(const char *, struct patch *);
 737                } optable[] = {
 738                        { "@@ -", gitdiff_hdrend },
 739                        { "--- ", gitdiff_oldname },
 740                        { "+++ ", gitdiff_newname },
 741                        { "old mode ", gitdiff_oldmode },
 742                        { "new mode ", gitdiff_newmode },
 743                        { "deleted file mode ", gitdiff_delete },
 744                        { "new file mode ", gitdiff_newfile },
 745                        { "copy from ", gitdiff_copysrc },
 746                        { "copy to ", gitdiff_copydst },
 747                        { "rename old ", gitdiff_renamesrc },
 748                        { "rename new ", gitdiff_renamedst },
 749                        { "rename from ", gitdiff_renamesrc },
 750                        { "rename to ", gitdiff_renamedst },
 751                        { "similarity index ", gitdiff_similarity },
 752                        { "dissimilarity index ", gitdiff_dissimilarity },
 753                        { "index ", gitdiff_index },
 754                        { "", gitdiff_unrecognized },
 755                };
 756                int i;
 757
 758                len = linelen(line, size);
 759                if (!len || line[len-1] != '\n')
 760                        break;
 761                for (i = 0; i < ARRAY_SIZE(optable); i++) {
 762                        const struct opentry *p = optable + i;
 763                        int oplen = strlen(p->str);
 764                        if (len < oplen || memcmp(p->str, line, oplen))
 765                                continue;
 766                        if (p->fn(line + oplen, patch) < 0)
 767                                return offset;
 768                        break;
 769                }
 770        }
 771
 772        return offset;
 773}
 774
 775static int parse_num(const char *line, unsigned long *p)
 776{
 777        char *ptr;
 778
 779        if (!isdigit(*line))
 780                return 0;
 781        *p = strtoul(line, &ptr, 10);
 782        return ptr - line;
 783}
 784
 785static int parse_range(const char *line, int len, int offset, const char *expect,
 786                        unsigned long *p1, unsigned long *p2)
 787{
 788        int digits, ex;
 789
 790        if (offset < 0 || offset >= len)
 791                return -1;
 792        line += offset;
 793        len -= offset;
 794
 795        digits = parse_num(line, p1);
 796        if (!digits)
 797                return -1;
 798
 799        offset += digits;
 800        line += digits;
 801        len -= digits;
 802
 803        *p2 = 1;
 804        if (*line == ',') {
 805                digits = parse_num(line+1, p2);
 806                if (!digits)
 807                        return -1;
 808
 809                offset += digits+1;
 810                line += digits+1;
 811                len -= digits+1;
 812        }
 813
 814        ex = strlen(expect);
 815        if (ex > len)
 816                return -1;
 817        if (memcmp(line, expect, ex))
 818                return -1;
 819
 820        return offset + ex;
 821}
 822
 823/*
 824 * Parse a unified diff fragment header of the
 825 * form "@@ -a,b +c,d @@"
 826 */
 827static int parse_fragment_header(char *line, int len, struct fragment *fragment)
 828{
 829        int offset;
 830
 831        if (!len || line[len-1] != '\n')
 832                return -1;
 833
 834        /* Figure out the number of lines in a fragment */
 835        offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
 836        offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 837
 838        return offset;
 839}
 840
 841static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
 842{
 843        unsigned long offset, len;
 844
 845        patch->is_toplevel_relative = 0;
 846        patch->is_rename = patch->is_copy = 0;
 847        patch->is_new = patch->is_delete = -1;
 848        patch->old_mode = patch->new_mode = 0;
 849        patch->old_name = patch->new_name = NULL;
 850        for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
 851                unsigned long nextlen;
 852
 853                len = linelen(line, size);
 854                if (!len)
 855                        break;
 856
 857                /* Testing this early allows us to take a few shortcuts.. */
 858                if (len < 6)
 859                        continue;
 860
 861                /*
 862                 * Make sure we don't find any unconnected patch fragments.
 863                 * That's a sign that we didn't find a header, and that a
 864                 * patch has become corrupted/broken up.
 865                 */
 866                if (!memcmp("@@ -", line, 4)) {
 867                        struct fragment dummy;
 868                        if (parse_fragment_header(line, len, &dummy) < 0)
 869                                continue;
 870                        die("patch fragment without header at line %d: %.*s",
 871                            linenr, (int)len-1, line);
 872                }
 873
 874                if (size < len + 6)
 875                        break;
 876
 877                /*
 878                 * Git patch? It might not have a real patch, just a rename
 879                 * or mode change, so we handle that specially
 880                 */
 881                if (!memcmp("diff --git ", line, 11)) {
 882                        int git_hdr_len = parse_git_header(line, len, size, patch);
 883                        if (git_hdr_len <= len)
 884                                continue;
 885                        if (!patch->old_name && !patch->new_name) {
 886                                if (!patch->def_name)
 887                                        die("git diff header lacks filename information (line %d)", linenr);
 888                                patch->old_name = patch->new_name = patch->def_name;
 889                        }
 890                        patch->is_toplevel_relative = 1;
 891                        *hdrsize = git_hdr_len;
 892                        return offset;
 893                }
 894
 895                /** --- followed by +++ ? */
 896                if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
 897                        continue;
 898
 899                /*
 900                 * We only accept unified patches, so we want it to
 901                 * at least have "@@ -a,b +c,d @@\n", which is 14 chars
 902                 * minimum
 903                 */
 904                nextlen = linelen(line + len, size - len);
 905                if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
 906                        continue;
 907
 908                /* Ok, we'll consider it a patch */
 909                parse_traditional_patch(line, line+len, patch);
 910                *hdrsize = len + nextlen;
 911                linenr += 2;
 912                return offset;
 913        }
 914        return -1;
 915}
 916
 917static void check_whitespace(const char *line, int len)
 918{
 919        const char *err = "Adds trailing whitespace";
 920        int seen_space = 0;
 921        int i;
 922
 923        /*
 924         * We know len is at least two, since we have a '+' and we
 925         * checked that the last character was a '\n' before calling
 926         * this function.  That is, an addition of an empty line would
 927         * check the '+' here.  Sneaky...
 928         */
 929        if (isspace(line[len-2]))
 930                goto error;
 931
 932        /*
 933         * Make sure that there is no space followed by a tab in
 934         * indentation.
 935         */
 936        err = "Space in indent is followed by a tab";
 937        for (i = 1; i < len; i++) {
 938                if (line[i] == '\t') {
 939                        if (seen_space)
 940                                goto error;
 941                }
 942                else if (line[i] == ' ')
 943                        seen_space = 1;
 944                else
 945                        break;
 946        }
 947        return;
 948
 949 error:
 950        whitespace_error++;
 951        if (squelch_whitespace_errors &&
 952            squelch_whitespace_errors < whitespace_error)
 953                ;
 954        else
 955                fprintf(stderr, "%s.\n%s:%d:%.*s\n",
 956                        err, patch_input_file, linenr, len-2, line+1);
 957}
 958
 959
 960/*
 961 * Parse a unified diff. Note that this really needs to parse each
 962 * fragment separately, since the only way to know the difference
 963 * between a "---" that is part of a patch, and a "---" that starts
 964 * the next patch is to look at the line counts..
 965 */
 966static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
 967{
 968        int added, deleted;
 969        int len = linelen(line, size), offset;
 970        unsigned long oldlines, newlines;
 971        unsigned long leading, trailing;
 972
 973        offset = parse_fragment_header(line, len, fragment);
 974        if (offset < 0)
 975                return -1;
 976        oldlines = fragment->oldlines;
 977        newlines = fragment->newlines;
 978        leading = 0;
 979        trailing = 0;
 980
 981        /* Parse the thing.. */
 982        line += len;
 983        size -= len;
 984        linenr++;
 985        added = deleted = 0;
 986        for (offset = len;
 987             0 < size;
 988             offset += len, size -= len, line += len, linenr++) {
 989                if (!oldlines && !newlines)
 990                        break;
 991                len = linelen(line, size);
 992                if (!len || line[len-1] != '\n')
 993                        return -1;
 994                switch (*line) {
 995                default:
 996                        return -1;
 997                case '\n': /* newer GNU diff, an empty context line */
 998                case ' ':
 999                        oldlines--;
1000                        newlines--;
1001                        if (!deleted && !added)
1002                                leading++;
1003                        trailing++;
1004                        break;
1005                case '-':
1006                        deleted++;
1007                        oldlines--;
1008                        trailing = 0;
1009                        break;
1010                case '+':
1011                        if (new_whitespace != nowarn_whitespace)
1012                                check_whitespace(line, len);
1013                        added++;
1014                        newlines--;
1015                        trailing = 0;
1016                        break;
1017
1018                /* We allow "\ No newline at end of file". Depending
1019                 * on locale settings when the patch was produced we
1020                 * don't know what this line looks like. The only
1021                 * thing we do know is that it begins with "\ ".
1022                 * Checking for 12 is just for sanity check -- any
1023                 * l10n of "\ No newline..." is at least that long.
1024                 */
1025                case '\\':
1026                        if (len < 12 || memcmp(line, "\\ ", 2))
1027                                return -1;
1028                        break;
1029                }
1030        }
1031        if (oldlines || newlines)
1032                return -1;
1033        fragment->leading = leading;
1034        fragment->trailing = trailing;
1035
1036        /* If a fragment ends with an incomplete line, we failed to include
1037         * it in the above loop because we hit oldlines == newlines == 0
1038         * before seeing it.
1039         */
1040        if (12 < size && !memcmp(line, "\\ ", 2))
1041                offset += linelen(line, size);
1042
1043        patch->lines_added += added;
1044        patch->lines_deleted += deleted;
1045
1046        if (0 < patch->is_new && oldlines)
1047                return error("new file depends on old contents");
1048        if (0 < patch->is_delete && newlines)
1049                return error("deleted file still has contents");
1050        return offset;
1051}
1052
1053static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
1054{
1055        unsigned long offset = 0;
1056        unsigned long oldlines = 0, newlines = 0, context = 0;
1057        struct fragment **fragp = &patch->fragments;
1058
1059        while (size > 4 && !memcmp(line, "@@ -", 4)) {
1060                struct fragment *fragment;
1061                int len;
1062
1063                fragment = xcalloc(1, sizeof(*fragment));
1064                len = parse_fragment(line, size, patch, fragment);
1065                if (len <= 0)
1066                        die("corrupt patch at line %d", linenr);
1067                fragment->patch = line;
1068                fragment->size = len;
1069                oldlines += fragment->oldlines;
1070                newlines += fragment->newlines;
1071                context += fragment->leading + fragment->trailing;
1072
1073                *fragp = fragment;
1074                fragp = &fragment->next;
1075
1076                offset += len;
1077                line += len;
1078                size -= len;
1079        }
1080
1081        /*
1082         * If something was removed (i.e. we have old-lines) it cannot
1083         * be creation, and if something was added it cannot be
1084         * deletion.  However, the reverse is not true; --unified=0
1085         * patches that only add are not necessarily creation even
1086         * though they do not have any old lines, and ones that only
1087         * delete are not necessarily deletion.
1088         *
1089         * Unfortunately, a real creation/deletion patch do _not_ have
1090         * any context line by definition, so we cannot safely tell it
1091         * apart with --unified=0 insanity.  At least if the patch has
1092         * more than one hunk it is not creation or deletion.
1093         */
1094        if (patch->is_new < 0 &&
1095            (oldlines || (patch->fragments && patch->fragments->next)))
1096                patch->is_new = 0;
1097        if (patch->is_delete < 0 &&
1098            (newlines || (patch->fragments && patch->fragments->next)))
1099                patch->is_delete = 0;
1100        if (!unidiff_zero || context) {
1101                /* If the user says the patch is not generated with
1102                 * --unified=0, or if we have seen context lines,
1103                 * then not having oldlines means the patch is creation,
1104                 * and not having newlines means the patch is deletion.
1105                 */
1106                if (patch->is_new < 0 && !oldlines) {
1107                        patch->is_new = 1;
1108                        patch->old_name = NULL;
1109                }
1110                if (patch->is_delete < 0 && !newlines) {
1111                        patch->is_delete = 1;
1112                        patch->new_name = NULL;
1113                }
1114        }
1115
1116        if (0 < patch->is_new && oldlines)
1117                die("new file %s depends on old contents", patch->new_name);
1118        if (0 < patch->is_delete && newlines)
1119                die("deleted file %s still has contents", patch->old_name);
1120        if (!patch->is_delete && !newlines && context)
1121                fprintf(stderr, "** warning: file %s becomes empty but "
1122                        "is not deleted\n", patch->new_name);
1123
1124        return offset;
1125}
1126
1127static inline int metadata_changes(struct patch *patch)
1128{
1129        return  patch->is_rename > 0 ||
1130                patch->is_copy > 0 ||
1131                patch->is_new > 0 ||
1132                patch->is_delete ||
1133                (patch->old_mode && patch->new_mode &&
1134                 patch->old_mode != patch->new_mode);
1135}
1136
1137static char *inflate_it(const void *data, unsigned long size,
1138                        unsigned long inflated_size)
1139{
1140        z_stream stream;
1141        void *out;
1142        int st;
1143
1144        memset(&stream, 0, sizeof(stream));
1145
1146        stream.next_in = (unsigned char *)data;
1147        stream.avail_in = size;
1148        stream.next_out = out = xmalloc(inflated_size);
1149        stream.avail_out = inflated_size;
1150        inflateInit(&stream);
1151        st = inflate(&stream, Z_FINISH);
1152        if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1153                free(out);
1154                return NULL;
1155        }
1156        return out;
1157}
1158
1159static struct fragment *parse_binary_hunk(char **buf_p,
1160                                          unsigned long *sz_p,
1161                                          int *status_p,
1162                                          int *used_p)
1163{
1164        /* Expect a line that begins with binary patch method ("literal"
1165         * or "delta"), followed by the length of data before deflating.
1166         * a sequence of 'length-byte' followed by base-85 encoded data
1167         * should follow, terminated by a newline.
1168         *
1169         * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1170         * and we would limit the patch line to 66 characters,
1171         * so one line can fit up to 13 groups that would decode
1172         * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1173         * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1174         */
1175        int llen, used;
1176        unsigned long size = *sz_p;
1177        char *buffer = *buf_p;
1178        int patch_method;
1179        unsigned long origlen;
1180        char *data = NULL;
1181        int hunk_size = 0;
1182        struct fragment *frag;
1183
1184        llen = linelen(buffer, size);
1185        used = llen;
1186
1187        *status_p = 0;
1188
1189        if (!prefixcmp(buffer, "delta ")) {
1190                patch_method = BINARY_DELTA_DEFLATED;
1191                origlen = strtoul(buffer + 6, NULL, 10);
1192        }
1193        else if (!prefixcmp(buffer, "literal ")) {
1194                patch_method = BINARY_LITERAL_DEFLATED;
1195                origlen = strtoul(buffer + 8, NULL, 10);
1196        }
1197        else
1198                return NULL;
1199
1200        linenr++;
1201        buffer += llen;
1202        while (1) {
1203                int byte_length, max_byte_length, newsize;
1204                llen = linelen(buffer, size);
1205                used += llen;
1206                linenr++;
1207                if (llen == 1) {
1208                        /* consume the blank line */
1209                        buffer++;
1210                        size--;
1211                        break;
1212                }
1213                /* Minimum line is "A00000\n" which is 7-byte long,
1214                 * and the line length must be multiple of 5 plus 2.
1215                 */
1216                if ((llen < 7) || (llen-2) % 5)
1217                        goto corrupt;
1218                max_byte_length = (llen - 2) / 5 * 4;
1219                byte_length = *buffer;
1220                if ('A' <= byte_length && byte_length <= 'Z')
1221                        byte_length = byte_length - 'A' + 1;
1222                else if ('a' <= byte_length && byte_length <= 'z')
1223                        byte_length = byte_length - 'a' + 27;
1224                else
1225                        goto corrupt;
1226                /* if the input length was not multiple of 4, we would
1227                 * have filler at the end but the filler should never
1228                 * exceed 3 bytes
1229                 */
1230                if (max_byte_length < byte_length ||
1231                    byte_length <= max_byte_length - 4)
1232                        goto corrupt;
1233                newsize = hunk_size + byte_length;
1234                data = xrealloc(data, newsize);
1235                if (decode_85(data + hunk_size, buffer + 1, byte_length))
1236                        goto corrupt;
1237                hunk_size = newsize;
1238                buffer += llen;
1239                size -= llen;
1240        }
1241
1242        frag = xcalloc(1, sizeof(*frag));
1243        frag->patch = inflate_it(data, hunk_size, origlen);
1244        if (!frag->patch)
1245                goto corrupt;
1246        free(data);
1247        frag->size = origlen;
1248        *buf_p = buffer;
1249        *sz_p = size;
1250        *used_p = used;
1251        frag->binary_patch_method = patch_method;
1252        return frag;
1253
1254 corrupt:
1255        free(data);
1256        *status_p = -1;
1257        error("corrupt binary patch at line %d: %.*s",
1258              linenr-1, llen-1, buffer);
1259        return NULL;
1260}
1261
1262static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
1263{
1264        /* We have read "GIT binary patch\n"; what follows is a line
1265         * that says the patch method (currently, either "literal" or
1266         * "delta") and the length of data before deflating; a
1267         * sequence of 'length-byte' followed by base-85 encoded data
1268         * follows.
1269         *
1270         * When a binary patch is reversible, there is another binary
1271         * hunk in the same format, starting with patch method (either
1272         * "literal" or "delta") with the length of data, and a sequence
1273         * of length-byte + base-85 encoded data, terminated with another
1274         * empty line.  This data, when applied to the postimage, produces
1275         * the preimage.
1276         */
1277        struct fragment *forward;
1278        struct fragment *reverse;
1279        int status;
1280        int used, used_1;
1281
1282        forward = parse_binary_hunk(&buffer, &size, &status, &used);
1283        if (!forward && !status)
1284                /* there has to be one hunk (forward hunk) */
1285                return error("unrecognized binary patch at line %d", linenr-1);
1286        if (status)
1287                /* otherwise we already gave an error message */
1288                return status;
1289
1290        reverse = parse_binary_hunk(&buffer, &size, &status, &used_1);
1291        if (reverse)
1292                used += used_1;
1293        else if (status) {
1294                /* not having reverse hunk is not an error, but having
1295                 * a corrupt reverse hunk is.
1296                 */
1297                free((void*) forward->patch);
1298                free(forward);
1299                return status;
1300        }
1301        forward->next = reverse;
1302        patch->fragments = forward;
1303        patch->is_binary = 1;
1304        return used;
1305}
1306
1307static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
1308{
1309        int hdrsize, patchsize;
1310        int offset = find_header(buffer, size, &hdrsize, patch);
1311
1312        if (offset < 0)
1313                return offset;
1314
1315        patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
1316
1317        if (!patchsize) {
1318                static const char *binhdr[] = {
1319                        "Binary files ",
1320                        "Files ",
1321                        NULL,
1322                };
1323                static const char git_binary[] = "GIT binary patch\n";
1324                int i;
1325                int hd = hdrsize + offset;
1326                unsigned long llen = linelen(buffer + hd, size - hd);
1327
1328                if (llen == sizeof(git_binary) - 1 &&
1329                    !memcmp(git_binary, buffer + hd, llen)) {
1330                        int used;
1331                        linenr++;
1332                        used = parse_binary(buffer + hd + llen,
1333                                            size - hd - llen, patch);
1334                        if (used)
1335                                patchsize = used + llen;
1336                        else
1337                                patchsize = 0;
1338                }
1339                else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
1340                        for (i = 0; binhdr[i]; i++) {
1341                                int len = strlen(binhdr[i]);
1342                                if (len < size - hd &&
1343                                    !memcmp(binhdr[i], buffer + hd, len)) {
1344                                        linenr++;
1345                                        patch->is_binary = 1;
1346                                        patchsize = llen;
1347                                        break;
1348                                }
1349                        }
1350                }
1351
1352                /* Empty patch cannot be applied if it is a text patch
1353                 * without metadata change.  A binary patch appears
1354                 * empty to us here.
1355                 */
1356                if ((apply || check) &&
1357                    (!patch->is_binary && !metadata_changes(patch)))
1358                        die("patch with only garbage at line %d", linenr);
1359        }
1360
1361        return offset + hdrsize + patchsize;
1362}
1363
1364#define swap(a,b) myswap((a),(b),sizeof(a))
1365
1366#define myswap(a, b, size) do {         \
1367        unsigned char mytmp[size];      \
1368        memcpy(mytmp, &a, size);                \
1369        memcpy(&a, &b, size);           \
1370        memcpy(&b, mytmp, size);                \
1371} while (0)
1372
1373static void reverse_patches(struct patch *p)
1374{
1375        for (; p; p = p->next) {
1376                struct fragment *frag = p->fragments;
1377
1378                swap(p->new_name, p->old_name);
1379                swap(p->new_mode, p->old_mode);
1380                swap(p->is_new, p->is_delete);
1381                swap(p->lines_added, p->lines_deleted);
1382                swap(p->old_sha1_prefix, p->new_sha1_prefix);
1383
1384                for (; frag; frag = frag->next) {
1385                        swap(frag->newpos, frag->oldpos);
1386                        swap(frag->newlines, frag->oldlines);
1387                }
1388        }
1389}
1390
1391static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
1392static const char minuses[]= "----------------------------------------------------------------------";
1393
1394static void show_stats(struct patch *patch)
1395{
1396        const char *prefix = "";
1397        char *name = patch->new_name;
1398        char *qname = NULL;
1399        int len, max, add, del, total;
1400
1401        if (!name)
1402                name = patch->old_name;
1403
1404        if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
1405                qname = xmalloc(len + 1);
1406                quote_c_style(name, qname, NULL, 0);
1407                name = qname;
1408        }
1409
1410        /*
1411         * "scale" the filename
1412         */
1413        len = strlen(name);
1414        max = max_len;
1415        if (max > 50)
1416                max = 50;
1417        if (len > max) {
1418                char *slash;
1419                prefix = "...";
1420                max -= 3;
1421                name += len - max;
1422                slash = strchr(name, '/');
1423                if (slash)
1424                        name = slash;
1425        }
1426        len = max;
1427
1428        /*
1429         * scale the add/delete
1430         */
1431        max = max_change;
1432        if (max + len > 70)
1433                max = 70 - len;
1434
1435        add = patch->lines_added;
1436        del = patch->lines_deleted;
1437        total = add + del;
1438
1439        if (max_change > 0) {
1440                total = (total * max + max_change / 2) / max_change;
1441                add = (add * max + max_change / 2) / max_change;
1442                del = total - add;
1443        }
1444        if (patch->is_binary)
1445                printf(" %s%-*s |  Bin\n", prefix, len, name);
1446        else
1447                printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
1448                       len, name, patch->lines_added + patch->lines_deleted,
1449                       add, pluses, del, minuses);
1450        free(qname);
1451}
1452
1453static int read_old_data(struct stat *st, const char *path, char **buf_p, unsigned long *alloc_p, unsigned long *size_p)
1454{
1455        int fd;
1456        unsigned long got;
1457        unsigned long nsize;
1458        char *nbuf;
1459        unsigned long size = *size_p;
1460        char *buf = *buf_p;
1461
1462        switch (st->st_mode & S_IFMT) {
1463        case S_IFLNK:
1464                return readlink(path, buf, size) != size;
1465        case S_IFREG:
1466                fd = open(path, O_RDONLY);
1467                if (fd < 0)
1468                        return error("unable to open %s", path);
1469                got = 0;
1470                for (;;) {
1471                        int ret = xread(fd, buf + got, size - got);
1472                        if (ret <= 0)
1473                                break;
1474                        got += ret;
1475                }
1476                close(fd);
1477                nsize = got;
1478                nbuf = buf;
1479                if (convert_to_git(path, &nbuf, &nsize)) {
1480                        free(buf);
1481                        *buf_p = nbuf;
1482                        *alloc_p = nsize;
1483                        *size_p = nsize;
1484                }
1485                return got != size;
1486        default:
1487                return -1;
1488        }
1489}
1490
1491static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
1492{
1493        int i;
1494        unsigned long start, backwards, forwards;
1495
1496        if (fragsize > size)
1497                return -1;
1498
1499        start = 0;
1500        if (line > 1) {
1501                unsigned long offset = 0;
1502                i = line-1;
1503                while (offset + fragsize <= size) {
1504                        if (buf[offset++] == '\n') {
1505                                start = offset;
1506                                if (!--i)
1507                                        break;
1508                        }
1509                }
1510        }
1511
1512        /* Exact line number? */
1513        if (!memcmp(buf + start, fragment, fragsize))
1514                return start;
1515
1516        /*
1517         * There's probably some smart way to do this, but I'll leave
1518         * that to the smart and beautiful people. I'm simple and stupid.
1519         */
1520        backwards = start;
1521        forwards = start;
1522        for (i = 0; ; i++) {
1523                unsigned long try;
1524                int n;
1525
1526                /* "backward" */
1527                if (i & 1) {
1528                        if (!backwards) {
1529                                if (forwards + fragsize > size)
1530                                        break;
1531                                continue;
1532                        }
1533                        do {
1534                                --backwards;
1535                        } while (backwards && buf[backwards-1] != '\n');
1536                        try = backwards;
1537                } else {
1538                        while (forwards + fragsize <= size) {
1539                                if (buf[forwards++] == '\n')
1540                                        break;
1541                        }
1542                        try = forwards;
1543                }
1544
1545                if (try + fragsize > size)
1546                        continue;
1547                if (memcmp(buf + try, fragment, fragsize))
1548                        continue;
1549                n = (i >> 1)+1;
1550                if (i & 1)
1551                        n = -n;
1552                *lines = n;
1553                return try;
1554        }
1555
1556        /*
1557         * We should start searching forward and backward.
1558         */
1559        return -1;
1560}
1561
1562static void remove_first_line(const char **rbuf, int *rsize)
1563{
1564        const char *buf = *rbuf;
1565        int size = *rsize;
1566        unsigned long offset;
1567        offset = 0;
1568        while (offset <= size) {
1569                if (buf[offset++] == '\n')
1570                        break;
1571        }
1572        *rsize = size - offset;
1573        *rbuf = buf + offset;
1574}
1575
1576static void remove_last_line(const char **rbuf, int *rsize)
1577{
1578        const char *buf = *rbuf;
1579        int size = *rsize;
1580        unsigned long offset;
1581        offset = size - 1;
1582        while (offset > 0) {
1583                if (buf[--offset] == '\n')
1584                        break;
1585        }
1586        *rsize = offset + 1;
1587}
1588
1589struct buffer_desc {
1590        char *buffer;
1591        unsigned long size;
1592        unsigned long alloc;
1593};
1594
1595static int apply_line(char *output, const char *patch, int plen)
1596{
1597        /* plen is number of bytes to be copied from patch,
1598         * starting at patch+1 (patch[0] is '+').  Typically
1599         * patch[plen] is '\n', unless this is the incomplete
1600         * last line.
1601         */
1602        int i;
1603        int add_nl_to_tail = 0;
1604        int fixed = 0;
1605        int last_tab_in_indent = -1;
1606        int last_space_in_indent = -1;
1607        int need_fix_leading_space = 0;
1608        char *buf;
1609
1610        if ((new_whitespace != strip_whitespace) || !whitespace_error ||
1611            *patch != '+') {
1612                memcpy(output, patch + 1, plen);
1613                return plen;
1614        }
1615
1616        if (1 < plen && isspace(patch[plen-1])) {
1617                if (patch[plen] == '\n')
1618                        add_nl_to_tail = 1;
1619                plen--;
1620                while (0 < plen && isspace(patch[plen]))
1621                        plen--;
1622                fixed = 1;
1623        }
1624
1625        for (i = 1; i < plen; i++) {
1626                char ch = patch[i];
1627                if (ch == '\t') {
1628                        last_tab_in_indent = i;
1629                        if (0 <= last_space_in_indent)
1630                                need_fix_leading_space = 1;
1631                }
1632                else if (ch == ' ')
1633                        last_space_in_indent = i;
1634                else
1635                        break;
1636        }
1637
1638        buf = output;
1639        if (need_fix_leading_space) {
1640                /* between patch[1..last_tab_in_indent] strip the
1641                 * funny spaces, updating them to tab as needed.
1642                 */
1643                for (i = 1; i < last_tab_in_indent; i++, plen--) {
1644                        char ch = patch[i];
1645                        if (ch != ' ')
1646                                *output++ = ch;
1647                        else if ((i % 8) == 0)
1648                                *output++ = '\t';
1649                }
1650                fixed = 1;
1651                i = last_tab_in_indent;
1652        }
1653        else
1654                i = 1;
1655
1656        memcpy(output, patch + i, plen);
1657        if (add_nl_to_tail)
1658                output[plen++] = '\n';
1659        if (fixed)
1660                applied_after_stripping++;
1661        return output + plen - buf;
1662}
1663
1664static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag, int inaccurate_eof)
1665{
1666        int match_beginning, match_end;
1667        char *buf = desc->buffer;
1668        const char *patch = frag->patch;
1669        int offset, size = frag->size;
1670        char *old = xmalloc(size);
1671        char *new = xmalloc(size);
1672        const char *oldlines, *newlines;
1673        int oldsize = 0, newsize = 0;
1674        unsigned long leading, trailing;
1675        int pos, lines;
1676
1677        while (size > 0) {
1678                char first;
1679                int len = linelen(patch, size);
1680                int plen;
1681
1682                if (!len)
1683                        break;
1684
1685                /*
1686                 * "plen" is how much of the line we should use for
1687                 * the actual patch data. Normally we just remove the
1688                 * first character on the line, but if the line is
1689                 * followed by "\ No newline", then we also remove the
1690                 * last one (which is the newline, of course).
1691                 */
1692                plen = len-1;
1693                if (len < size && patch[len] == '\\')
1694                        plen--;
1695                first = *patch;
1696                if (apply_in_reverse) {
1697                        if (first == '-')
1698                                first = '+';
1699                        else if (first == '+')
1700                                first = '-';
1701                }
1702                switch (first) {
1703                case '\n':
1704                        /* Newer GNU diff, empty context line */
1705                        if (plen < 0)
1706                                /* ... followed by '\No newline'; nothing */
1707                                break;
1708                        old[oldsize++] = '\n';
1709                        new[newsize++] = '\n';
1710                        break;
1711                case ' ':
1712                case '-':
1713                        memcpy(old + oldsize, patch + 1, plen);
1714                        oldsize += plen;
1715                        if (first == '-')
1716                                break;
1717                /* Fall-through for ' ' */
1718                case '+':
1719                        if (first != '+' || !no_add)
1720                                newsize += apply_line(new + newsize, patch,
1721                                                      plen);
1722                        break;
1723                case '@': case '\\':
1724                        /* Ignore it, we already handled it */
1725                        break;
1726                default:
1727                        if (apply_verbosely)
1728                                error("invalid start of line: '%c'", first);
1729                        return -1;
1730                }
1731                patch += len;
1732                size -= len;
1733        }
1734
1735        if (inaccurate_eof && oldsize > 0 && old[oldsize - 1] == '\n' &&
1736                        newsize > 0 && new[newsize - 1] == '\n') {
1737                oldsize--;
1738                newsize--;
1739        }
1740
1741        oldlines = old;
1742        newlines = new;
1743        leading = frag->leading;
1744        trailing = frag->trailing;
1745
1746        /*
1747         * If we don't have any leading/trailing data in the patch,
1748         * we want it to match at the beginning/end of the file.
1749         *
1750         * But that would break if the patch is generated with
1751         * --unified=0; sane people wouldn't do that to cause us
1752         * trouble, but we try to please not so sane ones as well.
1753         */
1754        if (unidiff_zero) {
1755                match_beginning = (!leading && !frag->oldpos);
1756                match_end = 0;
1757        }
1758        else {
1759                match_beginning = !leading && (frag->oldpos == 1);
1760                match_end = !trailing;
1761        }
1762
1763        lines = 0;
1764        pos = frag->newpos;
1765        for (;;) {
1766                offset = find_offset(buf, desc->size,
1767                                     oldlines, oldsize, pos, &lines);
1768                if (match_end && offset + oldsize != desc->size)
1769                        offset = -1;
1770                if (match_beginning && offset)
1771                        offset = -1;
1772                if (offset >= 0) {
1773                        int diff = newsize - oldsize;
1774                        unsigned long size = desc->size + diff;
1775                        unsigned long alloc = desc->alloc;
1776
1777                        /* Warn if it was necessary to reduce the number
1778                         * of context lines.
1779                         */
1780                        if ((leading != frag->leading) ||
1781                            (trailing != frag->trailing))
1782                                fprintf(stderr, "Context reduced to (%ld/%ld)"
1783                                        " to apply fragment at %d\n",
1784                                        leading, trailing, pos + lines);
1785
1786                        if (size > alloc) {
1787                                alloc = size + 8192;
1788                                desc->alloc = alloc;
1789                                buf = xrealloc(buf, alloc);
1790                                desc->buffer = buf;
1791                        }
1792                        desc->size = size;
1793                        memmove(buf + offset + newsize,
1794                                buf + offset + oldsize,
1795                                size - offset - newsize);
1796                        memcpy(buf + offset, newlines, newsize);
1797                        offset = 0;
1798
1799                        break;
1800                }
1801
1802                /* Am I at my context limits? */
1803                if ((leading <= p_context) && (trailing <= p_context))
1804                        break;
1805                if (match_beginning || match_end) {
1806                        match_beginning = match_end = 0;
1807                        continue;
1808                }
1809                /* Reduce the number of context lines
1810                 * Reduce both leading and trailing if they are equal
1811                 * otherwise just reduce the larger context.
1812                 */
1813                if (leading >= trailing) {
1814                        remove_first_line(&oldlines, &oldsize);
1815                        remove_first_line(&newlines, &newsize);
1816                        pos--;
1817                        leading--;
1818                }
1819                if (trailing > leading) {
1820                        remove_last_line(&oldlines, &oldsize);
1821                        remove_last_line(&newlines, &newsize);
1822                        trailing--;
1823                }
1824        }
1825
1826        if (offset && apply_verbosely)
1827                error("while searching for:\n%.*s", oldsize, oldlines);
1828
1829        free(old);
1830        free(new);
1831        return offset;
1832}
1833
1834static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch)
1835{
1836        unsigned long dst_size;
1837        struct fragment *fragment = patch->fragments;
1838        void *data;
1839        void *result;
1840
1841        /* Binary patch is irreversible without the optional second hunk */
1842        if (apply_in_reverse) {
1843                if (!fragment->next)
1844                        return error("cannot reverse-apply a binary patch "
1845                                     "without the reverse hunk to '%s'",
1846                                     patch->new_name
1847                                     ? patch->new_name : patch->old_name);
1848                fragment = fragment->next;
1849        }
1850        data = (void*) fragment->patch;
1851        switch (fragment->binary_patch_method) {
1852        case BINARY_DELTA_DEFLATED:
1853                result = patch_delta(desc->buffer, desc->size,
1854                                     data,
1855                                     fragment->size,
1856                                     &dst_size);
1857                free(desc->buffer);
1858                desc->buffer = result;
1859                break;
1860        case BINARY_LITERAL_DEFLATED:
1861                free(desc->buffer);
1862                desc->buffer = data;
1863                dst_size = fragment->size;
1864                break;
1865        }
1866        if (!desc->buffer)
1867                return -1;
1868        desc->size = desc->alloc = dst_size;
1869        return 0;
1870}
1871
1872static int apply_binary(struct buffer_desc *desc, struct patch *patch)
1873{
1874        const char *name = patch->old_name ? patch->old_name : patch->new_name;
1875        unsigned char sha1[20];
1876
1877        /* For safety, we require patch index line to contain
1878         * full 40-byte textual SHA1 for old and new, at least for now.
1879         */
1880        if (strlen(patch->old_sha1_prefix) != 40 ||
1881            strlen(patch->new_sha1_prefix) != 40 ||
1882            get_sha1_hex(patch->old_sha1_prefix, sha1) ||
1883            get_sha1_hex(patch->new_sha1_prefix, sha1))
1884                return error("cannot apply binary patch to '%s' "
1885                             "without full index line", name);
1886
1887        if (patch->old_name) {
1888                /* See if the old one matches what the patch
1889                 * applies to.
1890                 */
1891                hash_sha1_file(desc->buffer, desc->size, blob_type, sha1);
1892                if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
1893                        return error("the patch applies to '%s' (%s), "
1894                                     "which does not match the "
1895                                     "current contents.",
1896                                     name, sha1_to_hex(sha1));
1897        }
1898        else {
1899                /* Otherwise, the old one must be empty. */
1900                if (desc->size)
1901                        return error("the patch applies to an empty "
1902                                     "'%s' but it is not empty", name);
1903        }
1904
1905        get_sha1_hex(patch->new_sha1_prefix, sha1);
1906        if (is_null_sha1(sha1)) {
1907                free(desc->buffer);
1908                desc->alloc = desc->size = 0;
1909                desc->buffer = NULL;
1910                return 0; /* deletion patch */
1911        }
1912
1913        if (has_sha1_file(sha1)) {
1914                /* We already have the postimage */
1915                enum object_type type;
1916                unsigned long size;
1917
1918                free(desc->buffer);
1919                desc->buffer = read_sha1_file(sha1, &type, &size);
1920                if (!desc->buffer)
1921                        return error("the necessary postimage %s for "
1922                                     "'%s' cannot be read",
1923                                     patch->new_sha1_prefix, name);
1924                desc->alloc = desc->size = size;
1925        }
1926        else {
1927                /* We have verified desc matches the preimage;
1928                 * apply the patch data to it, which is stored
1929                 * in the patch->fragments->{patch,size}.
1930                 */
1931                if (apply_binary_fragment(desc, patch))
1932                        return error("binary patch does not apply to '%s'",
1933                                     name);
1934
1935                /* verify that the result matches */
1936                hash_sha1_file(desc->buffer, desc->size, blob_type, sha1);
1937                if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
1938                        return error("binary patch to '%s' creates incorrect result (expecting %s, got %s)", name, patch->new_sha1_prefix, sha1_to_hex(sha1));
1939        }
1940
1941        return 0;
1942}
1943
1944static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
1945{
1946        struct fragment *frag = patch->fragments;
1947        const char *name = patch->old_name ? patch->old_name : patch->new_name;
1948
1949        if (patch->is_binary)
1950                return apply_binary(desc, patch);
1951
1952        while (frag) {
1953                if (apply_one_fragment(desc, frag, patch->inaccurate_eof)) {
1954                        error("patch failed: %s:%ld", name, frag->oldpos);
1955                        if (!apply_with_reject)
1956                                return -1;
1957                        frag->rejected = 1;
1958                }
1959                frag = frag->next;
1960        }
1961        return 0;
1962}
1963
1964static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
1965{
1966        char *buf;
1967        unsigned long size, alloc;
1968        struct buffer_desc desc;
1969
1970        size = 0;
1971        alloc = 0;
1972        buf = NULL;
1973        if (cached) {
1974                if (ce) {
1975                        enum object_type type;
1976                        buf = read_sha1_file(ce->sha1, &type, &size);
1977                        if (!buf)
1978                                return error("read of %s failed",
1979                                             patch->old_name);
1980                        alloc = size;
1981                }
1982        }
1983        else if (patch->old_name) {
1984                size = st->st_size;
1985                alloc = size + 8192;
1986                buf = xmalloc(alloc);
1987                if (read_old_data(st, patch->old_name, &buf, &alloc, &size))
1988                        return error("read of %s failed", patch->old_name);
1989        }
1990
1991        desc.size = size;
1992        desc.alloc = alloc;
1993        desc.buffer = buf;
1994
1995        if (apply_fragments(&desc, patch) < 0)
1996                return -1; /* note with --reject this succeeds. */
1997
1998        /* NUL terminate the result */
1999        if (desc.alloc <= desc.size)
2000                desc.buffer = xrealloc(desc.buffer, desc.size + 1);
2001        desc.buffer[desc.size] = 0;
2002
2003        patch->result = desc.buffer;
2004        patch->resultsize = desc.size;
2005
2006        if (0 < patch->is_delete && patch->resultsize)
2007                return error("removal patch leaves file contents");
2008
2009        return 0;
2010}
2011
2012static int check_patch(struct patch *patch, struct patch *prev_patch)
2013{
2014        struct stat st;
2015        const char *old_name = patch->old_name;
2016        const char *new_name = patch->new_name;
2017        const char *name = old_name ? old_name : new_name;
2018        struct cache_entry *ce = NULL;
2019        int ok_if_exists;
2020
2021        patch->rejected = 1; /* we will drop this after we succeed */
2022        if (old_name) {
2023                int changed = 0;
2024                int stat_ret = 0;
2025                unsigned st_mode = 0;
2026
2027                if (!cached)
2028                        stat_ret = lstat(old_name, &st);
2029                if (check_index) {
2030                        int pos = cache_name_pos(old_name, strlen(old_name));
2031                        if (pos < 0)
2032                                return error("%s: does not exist in index",
2033                                             old_name);
2034                        ce = active_cache[pos];
2035                        if (stat_ret < 0) {
2036                                struct checkout costate;
2037                                if (errno != ENOENT)
2038                                        return error("%s: %s", old_name,
2039                                                     strerror(errno));
2040                                /* checkout */
2041                                costate.base_dir = "";
2042                                costate.base_dir_len = 0;
2043                                costate.force = 0;
2044                                costate.quiet = 0;
2045                                costate.not_new = 0;
2046                                costate.refresh_cache = 1;
2047                                if (checkout_entry(ce,
2048                                                   &costate,
2049                                                   NULL) ||
2050                                    lstat(old_name, &st))
2051                                        return -1;
2052                        }
2053                        if (!cached)
2054                                changed = ce_match_stat(ce, &st, 1);
2055                        if (changed)
2056                                return error("%s: does not match index",
2057                                             old_name);
2058                        if (cached)
2059                                st_mode = ntohl(ce->ce_mode);
2060                }
2061                else if (stat_ret < 0)
2062                        return error("%s: %s", old_name, strerror(errno));
2063
2064                if (!cached)
2065                        st_mode = ntohl(ce_mode_from_stat(ce, st.st_mode));
2066
2067                if (patch->is_new < 0)
2068                        patch->is_new = 0;
2069                if (!patch->old_mode)
2070                        patch->old_mode = st_mode;
2071                if ((st_mode ^ patch->old_mode) & S_IFMT)
2072                        return error("%s: wrong type", old_name);
2073                if (st_mode != patch->old_mode)
2074                        fprintf(stderr, "warning: %s has type %o, expected %o\n",
2075                                old_name, st_mode, patch->old_mode);
2076        }
2077
2078        if (new_name && prev_patch && 0 < prev_patch->is_delete &&
2079            !strcmp(prev_patch->old_name, new_name))
2080                /* A type-change diff is always split into a patch to
2081                 * delete old, immediately followed by a patch to
2082                 * create new (see diff.c::run_diff()); in such a case
2083                 * it is Ok that the entry to be deleted by the
2084                 * previous patch is still in the working tree and in
2085                 * the index.
2086                 */
2087                ok_if_exists = 1;
2088        else
2089                ok_if_exists = 0;
2090
2091        if (new_name &&
2092            ((0 < patch->is_new) | (0 < patch->is_rename) | patch->is_copy)) {
2093                if (check_index &&
2094                    cache_name_pos(new_name, strlen(new_name)) >= 0 &&
2095                    !ok_if_exists)
2096                        return error("%s: already exists in index", new_name);
2097                if (!cached) {
2098                        struct stat nst;
2099                        if (!lstat(new_name, &nst)) {
2100                                if (S_ISDIR(nst.st_mode) || ok_if_exists)
2101                                        ; /* ok */
2102                                else
2103                                        return error("%s: already exists in working directory", new_name);
2104                        }
2105                        else if ((errno != ENOENT) && (errno != ENOTDIR))
2106                                return error("%s: %s", new_name, strerror(errno));
2107                }
2108                if (!patch->new_mode) {
2109                        if (0 < patch->is_new)
2110                                patch->new_mode = S_IFREG | 0644;
2111                        else
2112                                patch->new_mode = patch->old_mode;
2113                }
2114        }
2115
2116        if (new_name && old_name) {
2117                int same = !strcmp(old_name, new_name);
2118                if (!patch->new_mode)
2119                        patch->new_mode = patch->old_mode;
2120                if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
2121                        return error("new mode (%o) of %s does not match old mode (%o)%s%s",
2122                                patch->new_mode, new_name, patch->old_mode,
2123                                same ? "" : " of ", same ? "" : old_name);
2124        }
2125
2126        if (apply_data(patch, &st, ce) < 0)
2127                return error("%s: patch does not apply", name);
2128        patch->rejected = 0;
2129        return 0;
2130}
2131
2132static int check_patch_list(struct patch *patch)
2133{
2134        struct patch *prev_patch = NULL;
2135        int err = 0;
2136
2137        for (prev_patch = NULL; patch ; patch = patch->next) {
2138                if (apply_verbosely)
2139                        say_patch_name(stderr,
2140                                       "Checking patch ", patch, "...\n");
2141                err |= check_patch(patch, prev_patch);
2142                prev_patch = patch;
2143        }
2144        return err;
2145}
2146
2147static void show_index_list(struct patch *list)
2148{
2149        struct patch *patch;
2150
2151        /* Once we start supporting the reverse patch, it may be
2152         * worth showing the new sha1 prefix, but until then...
2153         */
2154        for (patch = list; patch; patch = patch->next) {
2155                const unsigned char *sha1_ptr;
2156                unsigned char sha1[20];
2157                const char *name;
2158
2159                name = patch->old_name ? patch->old_name : patch->new_name;
2160                if (0 < patch->is_new)
2161                        sha1_ptr = null_sha1;
2162                else if (get_sha1(patch->old_sha1_prefix, sha1))
2163                        die("sha1 information is lacking or useless (%s).",
2164                            name);
2165                else
2166                        sha1_ptr = sha1;
2167
2168                printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
2169                if (line_termination && quote_c_style(name, NULL, NULL, 0))
2170                        quote_c_style(name, NULL, stdout, 0);
2171                else
2172                        fputs(name, stdout);
2173                putchar(line_termination);
2174        }
2175}
2176
2177static void stat_patch_list(struct patch *patch)
2178{
2179        int files, adds, dels;
2180
2181        for (files = adds = dels = 0 ; patch ; patch = patch->next) {
2182                files++;
2183                adds += patch->lines_added;
2184                dels += patch->lines_deleted;
2185                show_stats(patch);
2186        }
2187
2188        printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
2189}
2190
2191static void numstat_patch_list(struct patch *patch)
2192{
2193        for ( ; patch; patch = patch->next) {
2194                const char *name;
2195                name = patch->new_name ? patch->new_name : patch->old_name;
2196                if (patch->is_binary)
2197                        printf("-\t-\t");
2198                else
2199                        printf("%d\t%d\t",
2200                               patch->lines_added, patch->lines_deleted);
2201                if (line_termination && quote_c_style(name, NULL, NULL, 0))
2202                        quote_c_style(name, NULL, stdout, 0);
2203                else
2204                        fputs(name, stdout);
2205                putchar(line_termination);
2206        }
2207}
2208
2209static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
2210{
2211        if (mode)
2212                printf(" %s mode %06o %s\n", newdelete, mode, name);
2213        else
2214                printf(" %s %s\n", newdelete, name);
2215}
2216
2217static void show_mode_change(struct patch *p, int show_name)
2218{
2219        if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
2220                if (show_name)
2221                        printf(" mode change %06o => %06o %s\n",
2222                               p->old_mode, p->new_mode, p->new_name);
2223                else
2224                        printf(" mode change %06o => %06o\n",
2225                               p->old_mode, p->new_mode);
2226        }
2227}
2228
2229static void show_rename_copy(struct patch *p)
2230{
2231        const char *renamecopy = p->is_rename ? "rename" : "copy";
2232        const char *old, *new;
2233
2234        /* Find common prefix */
2235        old = p->old_name;
2236        new = p->new_name;
2237        while (1) {
2238                const char *slash_old, *slash_new;
2239                slash_old = strchr(old, '/');
2240                slash_new = strchr(new, '/');
2241                if (!slash_old ||
2242                    !slash_new ||
2243                    slash_old - old != slash_new - new ||
2244                    memcmp(old, new, slash_new - new))
2245                        break;
2246                old = slash_old + 1;
2247                new = slash_new + 1;
2248        }
2249        /* p->old_name thru old is the common prefix, and old and new
2250         * through the end of names are renames
2251         */
2252        if (old != p->old_name)
2253                printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
2254                       (int)(old - p->old_name), p->old_name,
2255                       old, new, p->score);
2256        else
2257                printf(" %s %s => %s (%d%%)\n", renamecopy,
2258                       p->old_name, p->new_name, p->score);
2259        show_mode_change(p, 0);
2260}
2261
2262static void summary_patch_list(struct patch *patch)
2263{
2264        struct patch *p;
2265
2266        for (p = patch; p; p = p->next) {
2267                if (p->is_new)
2268                        show_file_mode_name("create", p->new_mode, p->new_name);
2269                else if (p->is_delete)
2270                        show_file_mode_name("delete", p->old_mode, p->old_name);
2271                else {
2272                        if (p->is_rename || p->is_copy)
2273                                show_rename_copy(p);
2274                        else {
2275                                if (p->score) {
2276                                        printf(" rewrite %s (%d%%)\n",
2277                                               p->new_name, p->score);
2278                                        show_mode_change(p, 0);
2279                                }
2280                                else
2281                                        show_mode_change(p, 1);
2282                        }
2283                }
2284        }
2285}
2286
2287static void patch_stats(struct patch *patch)
2288{
2289        int lines = patch->lines_added + patch->lines_deleted;
2290
2291        if (lines > max_change)
2292                max_change = lines;
2293        if (patch->old_name) {
2294                int len = quote_c_style(patch->old_name, NULL, NULL, 0);
2295                if (!len)
2296                        len = strlen(patch->old_name);
2297                if (len > max_len)
2298                        max_len = len;
2299        }
2300        if (patch->new_name) {
2301                int len = quote_c_style(patch->new_name, NULL, NULL, 0);
2302                if (!len)
2303                        len = strlen(patch->new_name);
2304                if (len > max_len)
2305                        max_len = len;
2306        }
2307}
2308
2309static void remove_file(struct patch *patch, int rmdir_empty)
2310{
2311        if (write_index) {
2312                if (remove_file_from_cache(patch->old_name) < 0)
2313                        die("unable to remove %s from index", patch->old_name);
2314                cache_tree_invalidate_path(active_cache_tree, patch->old_name);
2315        }
2316        if (!cached) {
2317                if (!unlink(patch->old_name) && rmdir_empty) {
2318                        char *name = xstrdup(patch->old_name);
2319                        char *end = strrchr(name, '/');
2320                        while (end) {
2321                                *end = 0;
2322                                if (rmdir(name))
2323                                        break;
2324                                end = strrchr(name, '/');
2325                        }
2326                        free(name);
2327                }
2328        }
2329}
2330
2331static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
2332{
2333        struct stat st;
2334        struct cache_entry *ce;
2335        int namelen = strlen(path);
2336        unsigned ce_size = cache_entry_size(namelen);
2337
2338        if (!write_index)
2339                return;
2340
2341        ce = xcalloc(1, ce_size);
2342        memcpy(ce->name, path, namelen);
2343        ce->ce_mode = create_ce_mode(mode);
2344        ce->ce_flags = htons(namelen);
2345        if (!cached) {
2346                if (lstat(path, &st) < 0)
2347                        die("unable to stat newly created file %s", path);
2348                fill_stat_cache_info(ce, &st);
2349        }
2350        if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
2351                die("unable to create backing store for newly created file %s", path);
2352        if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
2353                die("unable to add cache entry for %s", path);
2354}
2355
2356static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
2357{
2358        int fd;
2359        char *nbuf;
2360        unsigned long nsize;
2361
2362        if (S_ISLNK(mode))
2363                /* Although buf:size is counted string, it also is NUL
2364                 * terminated.
2365                 */
2366                return symlink(buf, path);
2367        nsize = size;
2368        nbuf = (char *) buf;
2369        if (convert_to_working_tree(path, &nbuf, &nsize)) {
2370                free((char *) buf);
2371                buf = nbuf;
2372                size = nsize;
2373        }
2374
2375        fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
2376        if (fd < 0)
2377                return -1;
2378        while (size) {
2379                int written = xwrite(fd, buf, size);
2380                if (written < 0)
2381                        die("writing file %s: %s", path, strerror(errno));
2382                if (!written)
2383                        die("out of space writing file %s", path);
2384                buf += written;
2385                size -= written;
2386        }
2387        if (close(fd) < 0)
2388                die("closing file %s: %s", path, strerror(errno));
2389        return 0;
2390}
2391
2392/*
2393 * We optimistically assume that the directories exist,
2394 * which is true 99% of the time anyway. If they don't,
2395 * we create them and try again.
2396 */
2397static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
2398{
2399        if (cached)
2400                return;
2401        if (!try_create_file(path, mode, buf, size))
2402                return;
2403
2404        if (errno == ENOENT) {
2405                if (safe_create_leading_directories(path))
2406                        return;
2407                if (!try_create_file(path, mode, buf, size))
2408                        return;
2409        }
2410
2411        if (errno == EEXIST || errno == EACCES) {
2412                /* We may be trying to create a file where a directory
2413                 * used to be.
2414                 */
2415                struct stat st;
2416                errno = 0;
2417                if (!lstat(path, &st) && S_ISDIR(st.st_mode) && !rmdir(path))
2418                        errno = EEXIST;
2419        }
2420
2421        if (errno == EEXIST) {
2422                unsigned int nr = getpid();
2423
2424                for (;;) {
2425                        const char *newpath;
2426                        newpath = mkpath("%s~%u", path, nr);
2427                        if (!try_create_file(newpath, mode, buf, size)) {
2428                                if (!rename(newpath, path))
2429                                        return;
2430                                unlink(newpath);
2431                                break;
2432                        }
2433                        if (errno != EEXIST)
2434                                break;
2435                        ++nr;
2436                }
2437        }
2438        die("unable to write file %s mode %o", path, mode);
2439}
2440
2441static void create_file(struct patch *patch)
2442{
2443        char *path = patch->new_name;
2444        unsigned mode = patch->new_mode;
2445        unsigned long size = patch->resultsize;
2446        char *buf = patch->result;
2447
2448        if (!mode)
2449                mode = S_IFREG | 0644;
2450        create_one_file(path, mode, buf, size);
2451        add_index_file(path, mode, buf, size);
2452        cache_tree_invalidate_path(active_cache_tree, path);
2453}
2454
2455/* phase zero is to remove, phase one is to create */
2456static void write_out_one_result(struct patch *patch, int phase)
2457{
2458        if (patch->is_delete > 0) {
2459                if (phase == 0)
2460                        remove_file(patch, 1);
2461                return;
2462        }
2463        if (patch->is_new > 0 || patch->is_copy) {
2464                if (phase == 1)
2465                        create_file(patch);
2466                return;
2467        }
2468        /*
2469         * Rename or modification boils down to the same
2470         * thing: remove the old, write the new
2471         */
2472        if (phase == 0)
2473                remove_file(patch, 0);
2474        if (phase == 1)
2475                create_file(patch);
2476}
2477
2478static int write_out_one_reject(struct patch *patch)
2479{
2480        FILE *rej;
2481        char namebuf[PATH_MAX];
2482        struct fragment *frag;
2483        int cnt = 0;
2484
2485        for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
2486                if (!frag->rejected)
2487                        continue;
2488                cnt++;
2489        }
2490
2491        if (!cnt) {
2492                if (apply_verbosely)
2493                        say_patch_name(stderr,
2494                                       "Applied patch ", patch, " cleanly.\n");
2495                return 0;
2496        }
2497
2498        /* This should not happen, because a removal patch that leaves
2499         * contents are marked "rejected" at the patch level.
2500         */
2501        if (!patch->new_name)
2502                die("internal error");
2503
2504        /* Say this even without --verbose */
2505        say_patch_name(stderr, "Applying patch ", patch, " with");
2506        fprintf(stderr, " %d rejects...\n", cnt);
2507
2508        cnt = strlen(patch->new_name);
2509        if (ARRAY_SIZE(namebuf) <= cnt + 5) {
2510                cnt = ARRAY_SIZE(namebuf) - 5;
2511                fprintf(stderr,
2512                        "warning: truncating .rej filename to %.*s.rej",
2513                        cnt - 1, patch->new_name);
2514        }
2515        memcpy(namebuf, patch->new_name, cnt);
2516        memcpy(namebuf + cnt, ".rej", 5);
2517
2518        rej = fopen(namebuf, "w");
2519        if (!rej)
2520                return error("cannot open %s: %s", namebuf, strerror(errno));
2521
2522        /* Normal git tools never deal with .rej, so do not pretend
2523         * this is a git patch by saying --git nor give extended
2524         * headers.  While at it, maybe please "kompare" that wants
2525         * the trailing TAB and some garbage at the end of line ;-).
2526         */
2527        fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
2528                patch->new_name, patch->new_name);
2529        for (cnt = 1, frag = patch->fragments;
2530             frag;
2531             cnt++, frag = frag->next) {
2532                if (!frag->rejected) {
2533                        fprintf(stderr, "Hunk #%d applied cleanly.\n", cnt);
2534                        continue;
2535                }
2536                fprintf(stderr, "Rejected hunk #%d.\n", cnt);
2537                fprintf(rej, "%.*s", frag->size, frag->patch);
2538                if (frag->patch[frag->size-1] != '\n')
2539                        fputc('\n', rej);
2540        }
2541        fclose(rej);
2542        return -1;
2543}
2544
2545static int write_out_results(struct patch *list, int skipped_patch)
2546{
2547        int phase;
2548        int errs = 0;
2549        struct patch *l;
2550
2551        if (!list && !skipped_patch)
2552                return error("No changes");
2553
2554        for (phase = 0; phase < 2; phase++) {
2555                l = list;
2556                while (l) {
2557                        if (l->rejected)
2558                                errs = 1;
2559                        else {
2560                                write_out_one_result(l, phase);
2561                                if (phase == 1 && write_out_one_reject(l))
2562                                        errs = 1;
2563                        }
2564                        l = l->next;
2565                }
2566        }
2567        return errs;
2568}
2569
2570static struct lock_file lock_file;
2571
2572static struct excludes {
2573        struct excludes *next;
2574        const char *path;
2575} *excludes;
2576
2577static int use_patch(struct patch *p)
2578{
2579        const char *pathname = p->new_name ? p->new_name : p->old_name;
2580        struct excludes *x = excludes;
2581        while (x) {
2582                if (fnmatch(x->path, pathname, 0) == 0)
2583                        return 0;
2584                x = x->next;
2585        }
2586        if (0 < prefix_length) {
2587                int pathlen = strlen(pathname);
2588                if (pathlen <= prefix_length ||
2589                    memcmp(prefix, pathname, prefix_length))
2590                        return 0;
2591        }
2592        return 1;
2593}
2594
2595static void prefix_one(char **name)
2596{
2597        char *old_name = *name;
2598        if (!old_name)
2599                return;
2600        *name = xstrdup(prefix_filename(prefix, prefix_length, *name));
2601        free(old_name);
2602}
2603
2604static void prefix_patches(struct patch *p)
2605{
2606        if (!prefix || p->is_toplevel_relative)
2607                return;
2608        for ( ; p; p = p->next) {
2609                if (p->new_name == p->old_name) {
2610                        char *prefixed = p->new_name;
2611                        prefix_one(&prefixed);
2612                        p->new_name = p->old_name = prefixed;
2613                }
2614                else {
2615                        prefix_one(&p->new_name);
2616                        prefix_one(&p->old_name);
2617                }
2618        }
2619}
2620
2621static int apply_patch(int fd, const char *filename, int inaccurate_eof)
2622{
2623        unsigned long offset, size;
2624        char *buffer = read_patch_file(fd, &size);
2625        struct patch *list = NULL, **listp = &list;
2626        int skipped_patch = 0;
2627
2628        patch_input_file = filename;
2629        if (!buffer)
2630                return -1;
2631        offset = 0;
2632        while (size > 0) {
2633                struct patch *patch;
2634                int nr;
2635
2636                patch = xcalloc(1, sizeof(*patch));
2637                patch->inaccurate_eof = inaccurate_eof;
2638                nr = parse_chunk(buffer + offset, size, patch);
2639                if (nr < 0)
2640                        break;
2641                if (apply_in_reverse)
2642                        reverse_patches(patch);
2643                if (prefix)
2644                        prefix_patches(patch);
2645                if (use_patch(patch)) {
2646                        patch_stats(patch);
2647                        *listp = patch;
2648                        listp = &patch->next;
2649                }
2650                else {
2651                        /* perhaps free it a bit better? */
2652                        free(patch);
2653                        skipped_patch++;
2654                }
2655                offset += nr;
2656                size -= nr;
2657        }
2658
2659        if (whitespace_error && (new_whitespace == error_on_whitespace))
2660                apply = 0;
2661
2662        write_index = check_index && apply;
2663        if (write_index && newfd < 0)
2664                newfd = hold_lock_file_for_update(&lock_file,
2665                                                  get_index_file(), 1);
2666        if (check_index) {
2667                if (read_cache() < 0)
2668                        die("unable to read index file");
2669        }
2670
2671        if ((check || apply) &&
2672            check_patch_list(list) < 0 &&
2673            !apply_with_reject)
2674                exit(1);
2675
2676        if (apply && write_out_results(list, skipped_patch))
2677                exit(1);
2678
2679        if (show_index_info)
2680                show_index_list(list);
2681
2682        if (diffstat)
2683                stat_patch_list(list);
2684
2685        if (numstat)
2686                numstat_patch_list(list);
2687
2688        if (summary)
2689                summary_patch_list(list);
2690
2691        free(buffer);
2692        return 0;
2693}
2694
2695static int git_apply_config(const char *var, const char *value)
2696{
2697        if (!strcmp(var, "apply.whitespace")) {
2698                apply_default_whitespace = xstrdup(value);
2699                return 0;
2700        }
2701        return git_default_config(var, value);
2702}
2703
2704
2705int cmd_apply(int argc, const char **argv, const char *unused_prefix)
2706{
2707        int i;
2708        int read_stdin = 1;
2709        int inaccurate_eof = 0;
2710        int errs = 0;
2711        int is_not_gitdir = 0;
2712
2713        const char *whitespace_option = NULL;
2714
2715        prefix = setup_git_directory_gently(&is_not_gitdir);
2716        prefix_length = prefix ? strlen(prefix) : 0;
2717        git_config(git_apply_config);
2718        if (apply_default_whitespace)
2719                parse_whitespace_option(apply_default_whitespace);
2720
2721        for (i = 1; i < argc; i++) {
2722                const char *arg = argv[i];
2723                char *end;
2724                int fd;
2725
2726                if (!strcmp(arg, "-")) {
2727                        errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2728                        read_stdin = 0;
2729                        continue;
2730                }
2731                if (!prefixcmp(arg, "--exclude=")) {
2732                        struct excludes *x = xmalloc(sizeof(*x));
2733                        x->path = arg + 10;
2734                        x->next = excludes;
2735                        excludes = x;
2736                        continue;
2737                }
2738                if (!prefixcmp(arg, "-p")) {
2739                        p_value = atoi(arg + 2);
2740                        p_value_known = 1;
2741                        continue;
2742                }
2743                if (!strcmp(arg, "--no-add")) {
2744                        no_add = 1;
2745                        continue;
2746                }
2747                if (!strcmp(arg, "--stat")) {
2748                        apply = 0;
2749                        diffstat = 1;
2750                        continue;
2751                }
2752                if (!strcmp(arg, "--allow-binary-replacement") ||
2753                    !strcmp(arg, "--binary")) {
2754                        continue; /* now no-op */
2755                }
2756                if (!strcmp(arg, "--numstat")) {
2757                        apply = 0;
2758                        numstat = 1;
2759                        continue;
2760                }
2761                if (!strcmp(arg, "--summary")) {
2762                        apply = 0;
2763                        summary = 1;
2764                        continue;
2765                }
2766                if (!strcmp(arg, "--check")) {
2767                        apply = 0;
2768                        check = 1;
2769                        continue;
2770                }
2771                if (!strcmp(arg, "--index")) {
2772                        if (is_not_gitdir)
2773                                die("--index outside a repository");
2774                        check_index = 1;
2775                        continue;
2776                }
2777                if (!strcmp(arg, "--cached")) {
2778                        if (is_not_gitdir)
2779                                die("--cached outside a repository");
2780                        check_index = 1;
2781                        cached = 1;
2782                        continue;
2783                }
2784                if (!strcmp(arg, "--apply")) {
2785                        apply = 1;
2786                        continue;
2787                }
2788                if (!strcmp(arg, "--index-info")) {
2789                        apply = 0;
2790                        show_index_info = 1;
2791                        continue;
2792                }
2793                if (!strcmp(arg, "-z")) {
2794                        line_termination = 0;
2795                        continue;
2796                }
2797                if (!prefixcmp(arg, "-C")) {
2798                        p_context = strtoul(arg + 2, &end, 0);
2799                        if (*end != '\0')
2800                                die("unrecognized context count '%s'", arg + 2);
2801                        continue;
2802                }
2803                if (!prefixcmp(arg, "--whitespace=")) {
2804                        whitespace_option = arg + 13;
2805                        parse_whitespace_option(arg + 13);
2806                        continue;
2807                }
2808                if (!strcmp(arg, "-R") || !strcmp(arg, "--reverse")) {
2809                        apply_in_reverse = 1;
2810                        continue;
2811                }
2812                if (!strcmp(arg, "--unidiff-zero")) {
2813                        unidiff_zero = 1;
2814                        continue;
2815                }
2816                if (!strcmp(arg, "--reject")) {
2817                        apply = apply_with_reject = apply_verbosely = 1;
2818                        continue;
2819                }
2820                if (!strcmp(arg, "-v") || !strcmp(arg, "--verbose")) {
2821                        apply_verbosely = 1;
2822                        continue;
2823                }
2824                if (!strcmp(arg, "--inaccurate-eof")) {
2825                        inaccurate_eof = 1;
2826                        continue;
2827                }
2828                if (0 < prefix_length)
2829                        arg = prefix_filename(prefix, prefix_length, arg);
2830
2831                fd = open(arg, O_RDONLY);
2832                if (fd < 0)
2833                        usage(apply_usage);
2834                read_stdin = 0;
2835                set_default_whitespace_mode(whitespace_option);
2836                errs |= apply_patch(fd, arg, inaccurate_eof);
2837                close(fd);
2838        }
2839        set_default_whitespace_mode(whitespace_option);
2840        if (read_stdin)
2841                errs |= apply_patch(0, "<stdin>", inaccurate_eof);
2842        if (whitespace_error) {
2843                if (squelch_whitespace_errors &&
2844                    squelch_whitespace_errors < whitespace_error) {
2845                        int squelched =
2846                                whitespace_error - squelch_whitespace_errors;
2847                        fprintf(stderr, "warning: squelched %d "
2848                                "whitespace error%s\n",
2849                                squelched,
2850                                squelched == 1 ? "" : "s");
2851                }
2852                if (new_whitespace == error_on_whitespace)
2853                        die("%d line%s add%s trailing whitespaces.",
2854                            whitespace_error,
2855                            whitespace_error == 1 ? "" : "s",
2856                            whitespace_error == 1 ? "s" : "");
2857                if (applied_after_stripping)
2858                        fprintf(stderr, "warning: %d line%s applied after"
2859                                " stripping trailing whitespaces.\n",
2860                                applied_after_stripping,
2861                                applied_after_stripping == 1 ? "" : "s");
2862                else if (whitespace_error)
2863                        fprintf(stderr, "warning: %d line%s add%s trailing"
2864                                " whitespaces.\n",
2865                                whitespace_error,
2866                                whitespace_error == 1 ? "" : "s",
2867                                whitespace_error == 1 ? "s" : "");
2868        }
2869
2870        if (write_index) {
2871                if (write_cache(newfd, active_cache, active_nr) ||
2872                    close(newfd) || commit_lock_file(&lock_file))
2873                        die("Unable to write new index file");
2874        }
2875
2876        return !!errs;
2877}