diff.c

   1 /*
   2  * Copyright (C) 2005 Junio C Hamano
   3  */
   4 #include <sys/types.h>
   5 #include <sys/wait.h>
   6 #include <signal.h>
   7 #include "cache.h"
   8 #include "quote.h"
   9 #include "diff.h"
  10 #include "diffcore.h"
  11 #include "delta.h"
  12 #include "xdiff-interface.h"
  13
  14 static int use_size_cache;
  15
  16 int diff_rename_limit_default = -1;
  17
  18 int git_diff_config(const char *var, const char *value)
  19 {
  20         if (!strcmp(var, "diff.renamelimit")) {
  21                 diff_rename_limit_default = git_config_int(var, value);
  22                 return 0;
  23         }
  24
  25         return git_default_config(var, value);
  26 }
  27
  28 static char *quote_one(const char *str)
  29 {
  30         int needlen;
  31         char *xp;
  32
  33         if (!str)
  34                 return NULL;
  35         needlen = quote_c_style(str, NULL, NULL, 0);
  36         if (!needlen)
  37                 return strdup(str);
  38         xp = xmalloc(needlen + 1);
  39         quote_c_style(str, xp, NULL, 0);
  40         return xp;
  41 }
  42
  43 static char *quote_two(const char *one, const char *two)
  44 {
  45         int need_one = quote_c_style(one, NULL, NULL, 1);
  46         int need_two = quote_c_style(two, NULL, NULL, 1);
  47         char *xp;
  48
  49         if (need_one + need_two) {
  50                 if (!need_one) need_one = strlen(one);
  51                 if (!need_two) need_one = strlen(two);
  52
  53                 xp = xmalloc(need_one + need_two + 3);
  54                 xp[0] = '"';
  55                 quote_c_style(one, xp + 1, NULL, 1);
  56                 quote_c_style(two, xp + need_one + 1, NULL, 1);
  57                 strcpy(xp + need_one + need_two + 1, "\"");
  58                 return xp;
  59         }
  60         need_one = strlen(one);
  61         need_two = strlen(two);
  62         xp = xmalloc(need_one + need_two + 1);
  63         strcpy(xp, one);
  64         strcpy(xp + need_one, two);
  65         return xp;
  66 }
  67
  68 static const char *external_diff(void)
  69 {
  70         static const char *external_diff_cmd = NULL;
  71         static int done_preparing = 0;
  72
  73         if (done_preparing)
  74                 return external_diff_cmd;
  75         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
  76         done_preparing = 1;
  77         return external_diff_cmd;
  78 }
  79
  80 #define TEMPFILE_PATH_LEN               50
  81
  82 static struct diff_tempfile {
  83         const char *name; /* filename external diff should read from */
  84         char hex[41];
  85         char mode[10];
  86         char tmp_path[TEMPFILE_PATH_LEN];
  87 } diff_temp[2];
  88
  89 static int count_lines(const char *data, int size)
  90 {
  91         int count, ch, completely_empty = 1, nl_just_seen = 0;
  92         count = 0;
  93         while (0 < size--) {
  94                 ch = *data++;
  95                 if (ch == '\n') {
  96                         count++;
  97                         nl_just_seen = 1;
  98                         completely_empty = 0;
  99                 }
 100                 else {
 101                         nl_just_seen = 0;
 102                         completely_empty = 0;
 103                 }
 104         }
 105         if (completely_empty)
 106                 return 0;
 107         if (!nl_just_seen)
 108                 count++; /* no trailing newline */
 109         return count;
 110 }
 111
 112 static void print_line_count(int count)
 113 {
 114         switch (count) {
 115         case 0:
 116                 printf("0,0");
 117                 break;
 118         case 1:
 119                 printf("1");
 120                 break;
 121         default:
 122                 printf("1,%d", count);
 123                 break;
 124         }
 125 }
 126
 127 static void copy_file(int prefix, const char *data, int size)
 128 {
 129         int ch, nl_just_seen = 1;
 130         while (0 < size--) {
 131                 ch = *data++;
 132                 if (nl_just_seen)
 133                         putchar(prefix);
 134                 putchar(ch);
 135                 if (ch == '\n')
 136                         nl_just_seen = 1;
 137                 else
 138                         nl_just_seen = 0;
 139         }
 140         if (!nl_just_seen)
 141                 printf("\n\\ No newline at end of file\n");
 142 }
 143
 144 static void emit_rewrite_diff(const char *name_a,
 145                               const char *name_b,
 146                               struct diff_filespec *one,
 147                               struct diff_filespec *two)
 148 {
 149         int lc_a, lc_b;
 150         diff_populate_filespec(one, 0);
 151         diff_populate_filespec(two, 0);
 152         lc_a = count_lines(one->data, one->size);
 153         lc_b = count_lines(two->data, two->size);
 154         printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
 155         print_line_count(lc_a);
 156         printf(" +");
 157         print_line_count(lc_b);
 158         printf(" @@\n");
 159         if (lc_a)
 160                 copy_file('-', one->data, one->size);
 161         if (lc_b)
 162                 copy_file('+', two->data, two->size);
 163 }
 164
 165 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 166 {
 167         if (!DIFF_FILE_VALID(one)) {
 168                 mf->ptr = ""; /* does not matter */
 169                 mf->size = 0;
 170                 return 0;
 171         }
 172         else if (diff_populate_filespec(one, 0))
 173                 return -1;
 174         mf->ptr = one->data;
 175         mf->size = one->size;
 176         return 0;
 177 }
 178
 179 struct emit_callback {
 180         const char **label_path;
 181 };
 182
 183 static int fn_out(void *priv, mmbuffer_t *mb, int nbuf)
 184 {
 185         int i;
 186         struct emit_callback *ecbdata = priv;
 187
 188         if (ecbdata->label_path[0]) {
 189                 printf("--- %s\n", ecbdata->label_path[0]);
 190                 printf("+++ %s\n", ecbdata->label_path[1]);
 191                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
 192         }
 193         for (i = 0; i < nbuf; i++)
 194                 if (!fwrite(mb[i].ptr, mb[i].size, 1, stdout))
 195                         return -1;
 196         return 0;
 197 }
 198
 199 static char *pprint_rename(const char *a, const char *b)
 200 {
 201         const char *old = a;
 202         const char *new = b;
 203         char *name = NULL;
 204         int pfx_length, sfx_length;
 205         int len_a = strlen(a);
 206         int len_b = strlen(b);
 207
 208         /* Find common prefix */
 209         pfx_length = 0;
 210         while (*old && *new && *old == *new) {
 211                 if (*old == '/')
 212                         pfx_length = old - a + 1;
 213                 old++;
 214                 new++;
 215         }
 216
 217         /* Find common suffix */
 218         old = a + len_a;
 219         new = b + len_b;
 220         sfx_length = 0;
 221         while (a <= old && b <= new && *old == *new) {
 222                 if (*old == '/')
 223                         sfx_length = len_a - (old - a);
 224                 old--;
 225                 new--;
 226         }
 227
 228         /*
 229          * pfx{mid-a => mid-b}sfx
 230          * {pfx-a => pfx-b}sfx
 231          * pfx{sfx-a => sfx-b}
 232          * name-a => name-b
 233          */
 234         if (pfx_length + sfx_length) {
 235                 int a_midlen = len_a - pfx_length - sfx_length;
 236                 int b_midlen = len_b - pfx_length - sfx_length;
 237                 if (a_midlen < 0) a_midlen = 0;
 238                 if (b_midlen < 0) b_midlen = 0;
 239
 240                 name = xmalloc(len_a + len_b - pfx_length - sfx_length + 7);
 241                 sprintf(name, "%.*s{%.*s => %.*s}%s",
 242                         pfx_length, a,
 243                         a_midlen, a + pfx_length,
 244                         b_midlen, b + pfx_length,
 245                         a + len_a - sfx_length);
 246         }
 247         else {
 248                 name = xmalloc(len_a + len_b + 5);
 249                 sprintf(name, "%s => %s", a, b);
 250         }
 251         return name;
 252 }
 253
 254 struct diffstat_t {
 255         struct xdiff_emit_state xm;
 256
 257         int nr;
 258         int alloc;
 259         struct diffstat_file {
 260                 char *name;
 261                 unsigned is_unmerged:1;
 262                 unsigned is_binary:1;
 263                 unsigned is_renamed:1;
 264                 unsigned int added, deleted;
 265         } **files;
 266 };
 267
 268 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
 269                                           const char *name_a,
 270                                           const char *name_b)
 271 {
 272         struct diffstat_file *x;
 273         x = xcalloc(sizeof (*x), 1);
 274         if (diffstat->nr == diffstat->alloc) {
 275                 diffstat->alloc = alloc_nr(diffstat->alloc);
 276                 diffstat->files = xrealloc(diffstat->files,
 277                                 diffstat->alloc * sizeof(x));
 278         }
 279         diffstat->files[diffstat->nr++] = x;
 280         if (name_b) {
 281                 x->name = pprint_rename(name_a, name_b);
 282                 x->is_renamed = 1;
 283         }
 284         else
 285                 x->name = strdup(name_a);
 286         return x;
 287 }
 288
 289 static void diffstat_consume(void *priv, char *line, unsigned long len)
 290 {
 291         struct diffstat_t *diffstat = priv;
 292         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
 293
 294         if (line[0] == '+')
 295                 x->added++;
 296         else if (line[0] == '-')
 297                 x->deleted++;
 298 }
 299
 300 static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
 301 static const char minuses[]= "----------------------------------------------------------------------";
 302
 303 static void show_stats(struct diffstat_t* data)
 304 {
 305         int i, len, add, del, total, adds = 0, dels = 0;
 306         int max, max_change = 0, max_len = 0;
 307         int total_files = data->nr;
 308
 309         if (data->nr == 0)
 310                 return;
 311
 312         for (i = 0; i < data->nr; i++) {
 313                 struct diffstat_file *file = data->files[i];
 314
 315                 len = strlen(file->name);
 316                 if (max_len < len)
 317                         max_len = len;
 318
 319                 if (file->is_binary || file->is_unmerged)
 320                         continue;
 321                 if (max_change < file->added + file->deleted)
 322                         max_change = file->added + file->deleted;
 323         }
 324
 325         for (i = 0; i < data->nr; i++) {
 326                 char *prefix = "";
 327                 char *name = data->files[i]->name;
 328                 int added = data->files[i]->added;
 329                 int deleted = data->files[i]->deleted;
 330
 331                 if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
 332                         char *qname = xmalloc(len + 1);
 333                         quote_c_style(name, qname, NULL, 0);
 334                         free(name);
 335                         data->files[i]->name = name = qname;
 336                 }
 337
 338                 /*
 339                  * "scale" the filename
 340                  */
 341                 len = strlen(name);
 342                 max = max_len;
 343                 if (max > 50)
 344                         max = 50;
 345                 if (len > max) {
 346                         char *slash;
 347                         prefix = "...";
 348                         max -= 3;
 349                         name += len - max;
 350                         slash = strchr(name, '/');
 351                         if (slash)
 352                                 name = slash;
 353                 }
 354                 len = max;
 355
 356                 /*
 357                  * scale the add/delete
 358                  */
 359                 max = max_change;
 360                 if (max + len > 70)
 361                         max = 70 - len;
 362
 363                 if (data->files[i]->is_binary) {
 364                         printf(" %s%-*s |  Bin\n", prefix, len, name);
 365                         goto free_diffstat_file;
 366                 }
 367                 else if (data->files[i]->is_unmerged) {
 368                         printf(" %s%-*s |  Unmerged\n", prefix, len, name);
 369                         goto free_diffstat_file;
 370                 }
 371                 else if (!data->files[i]->is_renamed &&
 372                          (added + deleted == 0)) {
 373                         total_files--;
 374                         goto free_diffstat_file;
 375                 }
 376
 377                 add = added;
 378                 del = deleted;
 379                 total = add + del;
 380                 adds += add;
 381                 dels += del;
 382
 383                 if (max_change > 0) {
 384                         total = (total * max + max_change / 2) / max_change;
 385                         add = (add * max + max_change / 2) / max_change;
 386                         del = total - add;
 387                 }
 388                 printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
 389                                 len, name, added + deleted,
 390                                 add, pluses, del, minuses);
 391         free_diffstat_file:
 392                 free(data->files[i]->name);
 393                 free(data->files[i]);
 394         }
 395         free(data->files);
 396         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
 397                         total_files, adds, dels);
 398 }
 399
 400 struct checkdiff_t {
 401         struct xdiff_emit_state xm;
 402         const char *filename;
 403         int lineno;
 404 };
 405
 406 static void checkdiff_consume(void *priv, char *line, unsigned long len)
 407 {
 408         struct checkdiff_t *data = priv;
 409
 410         if (line[0] == '+') {
 411                 int i, spaces = 0;
 412
 413                 data->lineno++;
 414
 415                 /* check space before tab */
 416                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
 417                         if (line[i] == ' ')
 418                                 spaces++;
 419                 if (line[i - 1] == '\t' && spaces)
 420                         printf("%s:%d: space before tab:%.*s\n",
 421                                 data->filename, data->lineno, (int)len, line);
 422
 423                 /* check white space at line end */
 424                 if (line[len - 1] == '\n')
 425                         len--;
 426                 if (isspace(line[len - 1]))
 427                         printf("%s:%d: white space at end: %.*s\n",
 428                                 data->filename, data->lineno, (int)len, line);
 429         } else if (line[0] == ' ')
 430                 data->lineno++;
 431         else if (line[0] == '@') {
 432                 char *plus = strchr(line, '+');
 433                 if (plus)
 434                         data->lineno = strtol(plus, line + len, 10);
 435                 else
 436                         die("invalid diff");
 437         }
 438 }
 439
 440 static unsigned char *deflate_it(char *data,
 441                                  unsigned long size,
 442                                  unsigned long *result_size)
 443 {
 444         int bound;
 445         unsigned char *deflated;
 446         z_stream stream;
 447
 448         memset(&stream, 0, sizeof(stream));
 449         deflateInit(&stream, Z_BEST_COMPRESSION);
 450         bound = deflateBound(&stream, size);
 451         deflated = xmalloc(bound);
 452         stream.next_out = deflated;
 453         stream.avail_out = bound;
 454
 455         stream.next_in = (unsigned char *)data;
 456         stream.avail_in = size;
 457         while (deflate(&stream, Z_FINISH) == Z_OK)
 458                 ; /* nothing */
 459         deflateEnd(&stream);
 460         *result_size = stream.total_out;
 461         return deflated;
 462 }
 463
 464 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
 465 {
 466         void *cp;
 467         void *delta;
 468         void *deflated;
 469         void *data;
 470         unsigned long orig_size;
 471         unsigned long delta_size;
 472         unsigned long deflate_size;
 473         unsigned long data_size;
 474
 475         printf("GIT binary patch\n");
 476         /* We could do deflated delta, or we could do just deflated two,
 477          * whichever is smaller.
 478          */
 479         delta = NULL;
 480         deflated = deflate_it(two->ptr, two->size, &deflate_size);
 481         if (one->size && two->size) {
 482                 delta = diff_delta(one->ptr, one->size,
 483                                    two->ptr, two->size,
 484                                    &delta_size, deflate_size);
 485                 if (delta) {
 486                         void *to_free = delta;
 487                         orig_size = delta_size;
 488                         delta = deflate_it(delta, delta_size, &delta_size);
 489                         free(to_free);
 490                 }
 491         }
 492
 493         if (delta && delta_size < deflate_size) {
 494                 printf("delta %lu\n", orig_size);
 495                 free(deflated);
 496                 data = delta;
 497                 data_size = delta_size;
 498         }
 499         else {
 500                 printf("literal %lu\n", two->size);
 501                 free(delta);
 502                 data = deflated;
 503                 data_size = deflate_size;
 504         }
 505
 506         /* emit data encoded in base85 */
 507         cp = data;
 508         while (data_size) {
 509                 int bytes = (52 < data_size) ? 52 : data_size;
 510                 char line[70];
 511                 data_size -= bytes;
 512                 if (bytes <= 26)
 513                         line[0] = bytes + 'A' - 1;
 514                 else
 515                         line[0] = bytes - 26 + 'a' - 1;
 516                 encode_85(line + 1, cp, bytes);
 517                 cp += bytes;
 518                 puts(line);
 519         }
 520         printf("\n");
 521         free(data);
 522 }
 523
 524 #define FIRST_FEW_BYTES 8000
 525 static int mmfile_is_binary(mmfile_t *mf)
 526 {
 527         long sz = mf->size;
 528         if (FIRST_FEW_BYTES < sz)
 529                 sz = FIRST_FEW_BYTES;
 530         if (memchr(mf->ptr, 0, sz))
 531                 return 1;
 532         return 0;
 533 }
 534
 535 static void builtin_diff(const char *name_a,
 536                          const char *name_b,
 537                          struct diff_filespec *one,
 538                          struct diff_filespec *two,
 539                          const char *xfrm_msg,
 540                          struct diff_options *o,
 541                          int complete_rewrite)
 542 {
 543         mmfile_t mf1, mf2;
 544         const char *lbl[2];
 545         char *a_one, *b_two;
 546
 547         a_one = quote_two("a/", name_a);
 548         b_two = quote_two("b/", name_b);
 549         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
 550         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
 551         printf("diff --git %s %s\n", a_one, b_two);
 552         if (lbl[0][0] == '/') {
 553                 /* /dev/null */
 554                 printf("new file mode %06o\n", two->mode);
 555                 if (xfrm_msg && xfrm_msg[0])
 556                         puts(xfrm_msg);
 557         }
 558         else if (lbl[1][0] == '/') {
 559                 printf("deleted file mode %06o\n", one->mode);
 560                 if (xfrm_msg && xfrm_msg[0])
 561                         puts(xfrm_msg);
 562         }
 563         else {
 564                 if (one->mode != two->mode) {
 565                         printf("old mode %06o\n", one->mode);
 566                         printf("new mode %06o\n", two->mode);
 567                 }
 568                 if (xfrm_msg && xfrm_msg[0])
 569                         puts(xfrm_msg);
 570                 /*
 571                  * we do not run diff between different kind
 572                  * of objects.
 573                  */
 574                 if ((one->mode ^ two->mode) & S_IFMT)
 575                         goto free_ab_and_return;
 576                 if (complete_rewrite) {
 577                         emit_rewrite_diff(name_a, name_b, one, two);
 578                         goto free_ab_and_return;
 579                 }
 580         }
 581
 582         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 583                 die("unable to read files to diff");
 584
 585         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2)) {
 586                 /* Quite common confusing case */
 587                 if (mf1.size == mf2.size &&
 588                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
 589                         goto free_ab_and_return;
 590                 if (o->binary)
 591                         emit_binary_diff(&mf1, &mf2);
 592                 else
 593                         printf("Binary files %s and %s differ\n",
 594                                lbl[0], lbl[1]);
 595         }
 596         else {
 597                 /* Crazy xdl interfaces.. */
 598                 const char *diffopts = getenv("GIT_DIFF_OPTS");
 599                 xpparam_t xpp;
 600                 xdemitconf_t xecfg;
 601                 xdemitcb_t ecb;
 602                 struct emit_callback ecbdata;
 603
 604                 ecbdata.label_path = lbl;
 605                 xpp.flags = XDF_NEED_MINIMAL;
 606                 xecfg.ctxlen = o->context;
 607                 xecfg.flags = XDL_EMIT_FUNCNAMES;
 608                 if (!diffopts)
 609                         ;
 610                 else if (!strncmp(diffopts, "--unified=", 10))
 611                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
 612                 else if (!strncmp(diffopts, "-u", 2))
 613                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
 614                 ecb.outf = fn_out;
 615                 ecb.priv = &ecbdata;
 616                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 617         }
 618
 619  free_ab_and_return:
 620         free(a_one);
 621         free(b_two);
 622         return;
 623 }
 624
 625 static void builtin_diffstat(const char *name_a, const char *name_b,
 626                              struct diff_filespec *one,
 627                              struct diff_filespec *two,
 628                              struct diffstat_t *diffstat,
 629                              int complete_rewrite)
 630 {
 631         mmfile_t mf1, mf2;
 632         struct diffstat_file *data;
 633
 634         data = diffstat_add(diffstat, name_a, name_b);
 635
 636         if (!one || !two) {
 637                 data->is_unmerged = 1;
 638                 return;
 639         }
 640         if (complete_rewrite) {
 641                 diff_populate_filespec(one, 0);
 642                 diff_populate_filespec(two, 0);
 643                 data->deleted = count_lines(one->data, one->size);
 644                 data->added = count_lines(two->data, two->size);
 645                 return;
 646         }
 647         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 648                 die("unable to read files to diff");
 649
 650         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
 651                 data->is_binary = 1;
 652         else {
 653                 /* Crazy xdl interfaces.. */
 654                 xpparam_t xpp;
 655                 xdemitconf_t xecfg;
 656                 xdemitcb_t ecb;
 657
 658                 xpp.flags = XDF_NEED_MINIMAL;
 659                 xecfg.ctxlen = 0;
 660                 xecfg.flags = 0;
 661                 ecb.outf = xdiff_outf;
 662                 ecb.priv = diffstat;
 663                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 664         }
 665 }
 666
 667 static void builtin_checkdiff(const char *name_a, const char *name_b,
 668                              struct diff_filespec *one,
 669                              struct diff_filespec *two)
 670 {
 671         mmfile_t mf1, mf2;
 672         struct checkdiff_t data;
 673
 674         if (!two)
 675                 return;
 676
 677         memset(&data, 0, sizeof(data));
 678         data.xm.consume = checkdiff_consume;
 679         data.filename = name_b ? name_b : name_a;
 680         data.lineno = 0;
 681
 682         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 683                 die("unable to read files to diff");
 684
 685         if (mmfile_is_binary(&mf2))
 686                 return;
 687         else {
 688                 /* Crazy xdl interfaces.. */
 689                 xpparam_t xpp;
 690                 xdemitconf_t xecfg;
 691                 xdemitcb_t ecb;
 692
 693                 xpp.flags = XDF_NEED_MINIMAL;
 694                 xecfg.ctxlen = 0;
 695                 xecfg.flags = 0;
 696                 ecb.outf = xdiff_outf;
 697                 ecb.priv = &data;
 698                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 699         }
 700 }
 701
 702 struct diff_filespec *alloc_filespec(const char *path)
 703 {
 704         int namelen = strlen(path);
 705         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
 706
 707         memset(spec, 0, sizeof(*spec));
 708         spec->path = (char *)(spec + 1);
 709         memcpy(spec->path, path, namelen+1);
 710         return spec;
 711 }
 712
 713 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
 714                    unsigned short mode)
 715 {
 716         if (mode) {
 717                 spec->mode = canon_mode(mode);
 718                 memcpy(spec->sha1, sha1, 20);
 719                 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
 720         }
 721 }
 722
 723 /*
 724  * Given a name and sha1 pair, if the dircache tells us the file in
 725  * the work tree has that object contents, return true, so that
 726  * prepare_temp_file() does not have to inflate and extract.
 727  */
 728 static int work_tree_matches(const char *name, const unsigned char *sha1)
 729 {
 730         struct cache_entry *ce;
 731         struct stat st;
 732         int pos, len;
 733
 734         /* We do not read the cache ourselves here, because the
 735          * benchmark with my previous version that always reads cache
 736          * shows that it makes things worse for diff-tree comparing
 737          * two linux-2.6 kernel trees in an already checked out work
 738          * tree.  This is because most diff-tree comparisons deal with
 739          * only a small number of files, while reading the cache is
 740          * expensive for a large project, and its cost outweighs the
 741          * savings we get by not inflating the object to a temporary
 742          * file.  Practically, this code only helps when we are used
 743          * by diff-cache --cached, which does read the cache before
 744          * calling us.
 745          */
 746         if (!active_cache)
 747                 return 0;
 748
 749         len = strlen(name);
 750         pos = cache_name_pos(name, len);
 751         if (pos < 0)
 752                 return 0;
 753         ce = active_cache[pos];
 754         if ((lstat(name, &st) < 0) ||
 755             !S_ISREG(st.st_mode) || /* careful! */
 756             ce_match_stat(ce, &st, 0) ||
 757             memcmp(sha1, ce->sha1, 20))
 758                 return 0;
 759         /* we return 1 only when we can stat, it is a regular file,
 760          * stat information matches, and sha1 recorded in the cache
 761          * matches.  I.e. we know the file in the work tree really is
 762          * the same as the <name, sha1> pair.
 763          */
 764         return 1;
 765 }
 766
 767 static struct sha1_size_cache {
 768         unsigned char sha1[20];
 769         unsigned long size;
 770 } **sha1_size_cache;
 771 static int sha1_size_cache_nr, sha1_size_cache_alloc;
 772
 773 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
 774                                                  int find_only,
 775                                                  unsigned long size)
 776 {
 777         int first, last;
 778         struct sha1_size_cache *e;
 779
 780         first = 0;
 781         last = sha1_size_cache_nr;
 782         while (last > first) {
 783                 int cmp, next = (last + first) >> 1;
 784                 e = sha1_size_cache[next];
 785                 cmp = memcmp(e->sha1, sha1, 20);
 786                 if (!cmp)
 787                         return e;
 788                 if (cmp < 0) {
 789                         last = next;
 790                         continue;
 791                 }
 792                 first = next+1;
 793         }
 794         /* not found */
 795         if (find_only)
 796                 return NULL;
 797         /* insert to make it at "first" */
 798         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
 799                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
 800                 sha1_size_cache = xrealloc(sha1_size_cache,
 801                                            sha1_size_cache_alloc *
 802                                            sizeof(*sha1_size_cache));
 803         }
 804         sha1_size_cache_nr++;
 805         if (first < sha1_size_cache_nr)
 806                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
 807                         (sha1_size_cache_nr - first - 1) *
 808                         sizeof(*sha1_size_cache));
 809         e = xmalloc(sizeof(struct sha1_size_cache));
 810         sha1_size_cache[first] = e;
 811         memcpy(e->sha1, sha1, 20);
 812         e->size = size;
 813         return e;
 814 }
 815
 816 /*
 817  * While doing rename detection and pickaxe operation, we may need to
 818  * grab the data for the blob (or file) for our own in-core comparison.
 819  * diff_filespec has data and size fields for this purpose.
 820  */
 821 int diff_populate_filespec(struct diff_filespec *s, int size_only)
 822 {
 823         int err = 0;
 824         if (!DIFF_FILE_VALID(s))
 825                 die("internal error: asking to populate invalid file.");
 826         if (S_ISDIR(s->mode))
 827                 return -1;
 828
 829         if (!use_size_cache)
 830                 size_only = 0;
 831
 832         if (s->data)
 833                 return err;
 834         if (!s->sha1_valid ||
 835             work_tree_matches(s->path, s->sha1)) {
 836                 struct stat st;
 837                 int fd;
 838                 if (lstat(s->path, &st) < 0) {
 839                         if (errno == ENOENT) {
 840                         err_empty:
 841                                 err = -1;
 842                         empty:
 843                                 s->data = "";
 844                                 s->size = 0;
 845                                 return err;
 846                         }
 847                 }
 848                 s->size = st.st_size;
 849                 if (!s->size)
 850                         goto empty;
 851                 if (size_only)
 852                         return 0;
 853                 if (S_ISLNK(st.st_mode)) {
 854                         int ret;
 855                         s->data = xmalloc(s->size);
 856                         s->should_free = 1;
 857                         ret = readlink(s->path, s->data, s->size);
 858                         if (ret < 0) {
 859                                 free(s->data);
 860                                 goto err_empty;
 861                         }
 862                         return 0;
 863                 }
 864                 fd = open(s->path, O_RDONLY);
 865                 if (fd < 0)
 866                         goto err_empty;
 867                 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
 868                 close(fd);
 869                 if (s->data == MAP_FAILED)
 870                         goto err_empty;
 871                 s->should_munmap = 1;
 872         }
 873         else {
 874                 char type[20];
 875                 struct sha1_size_cache *e;
 876
 877                 if (size_only) {
 878                         e = locate_size_cache(s->sha1, 1, 0);
 879                         if (e) {
 880                                 s->size = e->size;
 881                                 return 0;
 882                         }
 883                         if (!sha1_object_info(s->sha1, type, &s->size))
 884                                 locate_size_cache(s->sha1, 0, s->size);
 885                 }
 886                 else {
 887                         s->data = read_sha1_file(s->sha1, type, &s->size);
 888                         s->should_free = 1;
 889                 }
 890         }
 891         return 0;
 892 }
 893
 894 void diff_free_filespec_data(struct diff_filespec *s)
 895 {
 896         if (s->should_free)
 897                 free(s->data);
 898         else if (s->should_munmap)
 899                 munmap(s->data, s->size);
 900         s->should_free = s->should_munmap = 0;
 901         s->data = NULL;
 902         free(s->cnt_data);
 903         s->cnt_data = NULL;
 904 }
 905
 906 static void prep_temp_blob(struct diff_tempfile *temp,
 907                            void *blob,
 908                            unsigned long size,
 909                            const unsigned char *sha1,
 910                            int mode)
 911 {
 912         int fd;
 913
 914         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
 915         if (fd < 0)
 916                 die("unable to create temp-file");
 917         if (write(fd, blob, size) != size)
 918                 die("unable to write temp-file");
 919         close(fd);
 920         temp->name = temp->tmp_path;
 921         strcpy(temp->hex, sha1_to_hex(sha1));
 922         temp->hex[40] = 0;
 923         sprintf(temp->mode, "%06o", mode);
 924 }
 925
 926 static void prepare_temp_file(const char *name,
 927                               struct diff_tempfile *temp,
 928                               struct diff_filespec *one)
 929 {
 930         if (!DIFF_FILE_VALID(one)) {
 931         not_a_valid_file:
 932                 /* A '-' entry produces this for file-2, and
 933                  * a '+' entry produces this for file-1.
 934                  */
 935                 temp->name = "/dev/null";
 936                 strcpy(temp->hex, ".");
 937                 strcpy(temp->mode, ".");
 938                 return;
 939         }
 940
 941         if (!one->sha1_valid ||
 942             work_tree_matches(name, one->sha1)) {
 943                 struct stat st;
 944                 if (lstat(name, &st) < 0) {
 945                         if (errno == ENOENT)
 946                                 goto not_a_valid_file;
 947                         die("stat(%s): %s", name, strerror(errno));
 948                 }
 949                 if (S_ISLNK(st.st_mode)) {
 950                         int ret;
 951                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
 952                         if (sizeof(buf) <= st.st_size)
 953                                 die("symlink too long: %s", name);
 954                         ret = readlink(name, buf, st.st_size);
 955                         if (ret < 0)
 956                                 die("readlink(%s)", name);
 957                         prep_temp_blob(temp, buf, st.st_size,
 958                                        (one->sha1_valid ?
 959                                         one->sha1 : null_sha1),
 960                                        (one->sha1_valid ?
 961                                         one->mode : S_IFLNK));
 962                 }
 963                 else {
 964                         /* we can borrow from the file in the work tree */
 965                         temp->name = name;
 966                         if (!one->sha1_valid)
 967                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
 968                         else
 969                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
 970                         /* Even though we may sometimes borrow the
 971                          * contents from the work tree, we always want
 972                          * one->mode.  mode is trustworthy even when
 973                          * !(one->sha1_valid), as long as
 974                          * DIFF_FILE_VALID(one).
 975                          */
 976                         sprintf(temp->mode, "%06o", one->mode);
 977                 }
 978                 return;
 979         }
 980         else {
 981                 if (diff_populate_filespec(one, 0))
 982                         die("cannot read data blob for %s", one->path);
 983                 prep_temp_blob(temp, one->data, one->size,
 984                                one->sha1, one->mode);
 985         }
 986 }
 987
 988 static void remove_tempfile(void)
 989 {
 990         int i;
 991
 992         for (i = 0; i < 2; i++)
 993                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
 994                         unlink(diff_temp[i].name);
 995                         diff_temp[i].name = NULL;
 996                 }
 997 }
 998
 999 static void remove_tempfile_on_signal(int signo)
1000 {
1001         remove_tempfile();
1002         signal(SIGINT, SIG_DFL);
1003         raise(signo);
1004 }
1005
1006 static int spawn_prog(const char *pgm, const char **arg)
1007 {
1008         pid_t pid;
1009         int status;
1010
1011         fflush(NULL);
1012         pid = fork();
1013         if (pid < 0)
1014                 die("unable to fork");
1015         if (!pid) {
1016                 execvp(pgm, (char *const*) arg);
1017                 exit(255);
1018         }
1019
1020         while (waitpid(pid, &status, 0) < 0) {
1021                 if (errno == EINTR)
1022                         continue;
1023                 return -1;
1024         }
1025
1026         /* Earlier we did not check the exit status because
1027          * diff exits non-zero if files are different, and
1028          * we are not interested in knowing that.  It was a
1029          * mistake which made it harder to quit a diff-*
1030          * session that uses the git-apply-patch-script as
1031          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1032          * should also exit non-zero only when it wants to
1033          * abort the entire diff-* session.
1034          */
1035         if (WIFEXITED(status) && !WEXITSTATUS(status))
1036                 return 0;
1037         return -1;
1038 }
1039
1040 /* An external diff command takes:
1041  *
1042  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1043  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1044  *
1045  */
1046 static void run_external_diff(const char *pgm,
1047                               const char *name,
1048                               const char *other,
1049                               struct diff_filespec *one,
1050                               struct diff_filespec *two,
1051                               const char *xfrm_msg,
1052                               int complete_rewrite)
1053 {
1054         const char *spawn_arg[10];
1055         struct diff_tempfile *temp = diff_temp;
1056         int retval;
1057         static int atexit_asked = 0;
1058         const char *othername;
1059         const char **arg = &spawn_arg[0];
1060
1061         othername = (other? other : name);
1062         if (one && two) {
1063                 prepare_temp_file(name, &temp[0], one);
1064                 prepare_temp_file(othername, &temp[1], two);
1065                 if (! atexit_asked &&
1066                     (temp[0].name == temp[0].tmp_path ||
1067                      temp[1].name == temp[1].tmp_path)) {
1068                         atexit_asked = 1;
1069                         atexit(remove_tempfile);
1070                 }
1071                 signal(SIGINT, remove_tempfile_on_signal);
1072         }
1073
1074         if (one && two) {
1075                 *arg++ = pgm;
1076                 *arg++ = name;
1077                 *arg++ = temp[0].name;
1078                 *arg++ = temp[0].hex;
1079                 *arg++ = temp[0].mode;
1080                 *arg++ = temp[1].name;
1081                 *arg++ = temp[1].hex;
1082                 *arg++ = temp[1].mode;
1083                 if (other) {
1084                         *arg++ = other;
1085                         *arg++ = xfrm_msg;
1086                 }
1087         } else {
1088                 *arg++ = pgm;
1089                 *arg++ = name;
1090         }
1091         *arg = NULL;
1092         retval = spawn_prog(pgm, spawn_arg);
1093         remove_tempfile();
1094         if (retval) {
1095                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1096                 exit(1);
1097         }
1098 }
1099
1100 static void run_diff_cmd(const char *pgm,
1101                          const char *name,
1102                          const char *other,
1103                          struct diff_filespec *one,
1104                          struct diff_filespec *two,
1105                          const char *xfrm_msg,
1106                          struct diff_options *o,
1107                          int complete_rewrite)
1108 {
1109         if (pgm) {
1110                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1111                                   complete_rewrite);
1112                 return;
1113         }
1114         if (one && two)
1115                 builtin_diff(name, other ? other : name,
1116                              one, two, xfrm_msg, o, complete_rewrite);
1117         else
1118                 printf("* Unmerged path %s\n", name);
1119 }
1120
1121 static void diff_fill_sha1_info(struct diff_filespec *one)
1122 {
1123         if (DIFF_FILE_VALID(one)) {
1124                 if (!one->sha1_valid) {
1125                         struct stat st;
1126                         if (lstat(one->path, &st) < 0)
1127                                 die("stat %s", one->path);
1128                         if (index_path(one->sha1, one->path, &st, 0))
1129                                 die("cannot hash %s\n", one->path);
1130                 }
1131         }
1132         else
1133                 memset(one->sha1, 0, 20);
1134 }
1135
1136 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1137 {
1138         const char *pgm = external_diff();
1139         char msg[PATH_MAX*2+300], *xfrm_msg;
1140         struct diff_filespec *one;
1141         struct diff_filespec *two;
1142         const char *name;
1143         const char *other;
1144         char *name_munged, *other_munged;
1145         int complete_rewrite = 0;
1146         int len;
1147
1148         if (DIFF_PAIR_UNMERGED(p)) {
1149                 /* unmerged */
1150                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1151                 return;
1152         }
1153
1154         name = p->one->path;
1155         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1156         name_munged = quote_one(name);
1157         other_munged = quote_one(other);
1158         one = p->one; two = p->two;
1159
1160         diff_fill_sha1_info(one);
1161         diff_fill_sha1_info(two);
1162
1163         len = 0;
1164         switch (p->status) {
1165         case DIFF_STATUS_COPIED:
1166                 len += snprintf(msg + len, sizeof(msg) - len,
1167                                 "similarity index %d%%\n"
1168                                 "copy from %s\n"
1169                                 "copy to %s\n",
1170                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1171                                 name_munged, other_munged);
1172                 break;
1173         case DIFF_STATUS_RENAMED:
1174                 len += snprintf(msg + len, sizeof(msg) - len,
1175                                 "similarity index %d%%\n"
1176                                 "rename from %s\n"
1177                                 "rename to %s\n",
1178                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1179                                 name_munged, other_munged);
1180                 break;
1181         case DIFF_STATUS_MODIFIED:
1182                 if (p->score) {
1183                         len += snprintf(msg + len, sizeof(msg) - len,
1184                                         "dissimilarity index %d%%\n",
1185                                         (int)(0.5 + p->score *
1186                                               100.0/MAX_SCORE));
1187                         complete_rewrite = 1;
1188                         break;
1189                 }
1190                 /* fallthru */
1191         default:
1192                 /* nothing */
1193                 ;
1194         }
1195
1196         if (memcmp(one->sha1, two->sha1, 20)) {
1197                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1198
1199                 len += snprintf(msg + len, sizeof(msg) - len,
1200                                 "index %.*s..%.*s",
1201                                 abbrev, sha1_to_hex(one->sha1),
1202                                 abbrev, sha1_to_hex(two->sha1));
1203                 if (one->mode == two->mode)
1204                         len += snprintf(msg + len, sizeof(msg) - len,
1205                                         " %06o", one->mode);
1206                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1207         }
1208
1209         if (len)
1210                 msg[--len] = 0;
1211         xfrm_msg = len ? msg : NULL;
1212
1213         if (!pgm &&
1214             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1215             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1216                 /* a filepair that changes between file and symlink
1217                  * needs to be split into deletion and creation.
1218                  */
1219                 struct diff_filespec *null = alloc_filespec(two->path);
1220                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1221                 free(null);
1222                 null = alloc_filespec(one->path);
1223                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1224                 free(null);
1225         }
1226         else
1227                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1228                              complete_rewrite);
1229
1230         free(name_munged);
1231         free(other_munged);
1232 }
1233
1234 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1235                          struct diffstat_t *diffstat)
1236 {
1237         const char *name;
1238         const char *other;
1239         int complete_rewrite = 0;
1240
1241         if (DIFF_PAIR_UNMERGED(p)) {
1242                 /* unmerged */
1243                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, 0);
1244                 return;
1245         }
1246
1247         name = p->one->path;
1248         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1249
1250         diff_fill_sha1_info(p->one);
1251         diff_fill_sha1_info(p->two);
1252
1253         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1254                 complete_rewrite = 1;
1255         builtin_diffstat(name, other, p->one, p->two, diffstat, complete_rewrite);
1256 }
1257
1258 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1259 {
1260         const char *name;
1261         const char *other;
1262
1263         if (DIFF_PAIR_UNMERGED(p)) {
1264                 /* unmerged */
1265                 return;
1266         }
1267
1268         name = p->one->path;
1269         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1270
1271         diff_fill_sha1_info(p->one);
1272         diff_fill_sha1_info(p->two);
1273
1274         builtin_checkdiff(name, other, p->one, p->two);
1275 }
1276
1277 void diff_setup(struct diff_options *options)
1278 {
1279         memset(options, 0, sizeof(*options));
1280         options->output_format = DIFF_FORMAT_RAW;
1281         options->line_termination = '\n';
1282         options->break_opt = -1;
1283         options->rename_limit = -1;
1284         options->context = 3;
1285
1286         options->change = diff_change;
1287         options->add_remove = diff_addremove;
1288 }
1289
1290 int diff_setup_done(struct diff_options *options)
1291 {
1292         if ((options->find_copies_harder &&
1293              options->detect_rename != DIFF_DETECT_COPY) ||
1294             (0 <= options->rename_limit && !options->detect_rename))
1295                 return -1;
1296
1297         /*
1298          * These cases always need recursive; we do not drop caller-supplied
1299          * recursive bits for other formats here.
1300          */
1301         if ((options->output_format == DIFF_FORMAT_PATCH) ||
1302             (options->output_format == DIFF_FORMAT_DIFFSTAT) ||
1303             (options->output_format == DIFF_FORMAT_CHECKDIFF))
1304                 options->recursive = 1;
1305
1306         if (options->detect_rename && options->rename_limit < 0)
1307                 options->rename_limit = diff_rename_limit_default;
1308         if (options->setup & DIFF_SETUP_USE_CACHE) {
1309                 if (!active_cache)
1310                         /* read-cache does not die even when it fails
1311                          * so it is safe for us to do this here.  Also
1312                          * it does not smudge active_cache or active_nr
1313                          * when it fails, so we do not have to worry about
1314                          * cleaning it up ourselves either.
1315                          */
1316                         read_cache();
1317         }
1318         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1319                 use_size_cache = 1;
1320         if (options->abbrev <= 0 || 40 < options->abbrev)
1321                 options->abbrev = 40; /* full */
1322
1323         return 0;
1324 }
1325
1326 int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1327 {
1328         char c, *eq;
1329         int len;
1330
1331         if (*arg != '-')
1332                 return 0;
1333         c = *++arg;
1334         if (!c)
1335                 return 0;
1336         if (c == arg_short) {
1337                 c = *++arg;
1338                 if (!c)
1339                         return 1;
1340                 if (val && isdigit(c)) {
1341                         char *end;
1342                         int n = strtoul(arg, &end, 10);
1343                         if (*end)
1344                                 return 0;
1345                         *val = n;
1346                         return 1;
1347                 }
1348                 return 0;
1349         }
1350         if (c != '-')
1351                 return 0;
1352         arg++;
1353         eq = strchr(arg, '=');
1354         if (eq)
1355                 len = eq - arg;
1356         else
1357                 len = strlen(arg);
1358         if (!len || strncmp(arg, arg_long, len))
1359                 return 0;
1360         if (eq) {
1361                 int n;
1362                 char *end;
1363                 if (!isdigit(*++eq))
1364                         return 0;
1365                 n = strtoul(eq, &end, 10);
1366                 if (*end)
1367                         return 0;
1368                 *val = n;
1369         }
1370         return 1;
1371 }
1372
1373 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1374 {
1375         const char *arg = av[0];
1376         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1377                 options->output_format = DIFF_FORMAT_PATCH;
1378         else if (opt_arg(arg, 'U', "unified", &options->context))
1379                 options->output_format = DIFF_FORMAT_PATCH;
1380         else if (!strcmp(arg, "--patch-with-raw")) {
1381                 options->output_format = DIFF_FORMAT_PATCH;
1382                 options->with_raw = 1;
1383         }
1384         else if (!strcmp(arg, "--stat"))
1385                 options->output_format = DIFF_FORMAT_DIFFSTAT;
1386         else if (!strcmp(arg, "--check"))
1387                 options->output_format = DIFF_FORMAT_CHECKDIFF;
1388         else if (!strcmp(arg, "--summary"))
1389                 options->summary = 1;
1390         else if (!strcmp(arg, "--patch-with-stat")) {
1391                 options->output_format = DIFF_FORMAT_PATCH;
1392                 options->with_stat = 1;
1393         }
1394         else if (!strcmp(arg, "-z"))
1395                 options->line_termination = 0;
1396         else if (!strncmp(arg, "-l", 2))
1397                 options->rename_limit = strtoul(arg+2, NULL, 10);
1398         else if (!strcmp(arg, "--full-index"))
1399                 options->full_index = 1;
1400         else if (!strcmp(arg, "--binary")) {
1401                 options->output_format = DIFF_FORMAT_PATCH;
1402                 options->full_index = options->binary = 1;
1403         }
1404         else if (!strcmp(arg, "--name-only"))
1405                 options->output_format = DIFF_FORMAT_NAME;
1406         else if (!strcmp(arg, "--name-status"))
1407                 options->output_format = DIFF_FORMAT_NAME_STATUS;
1408         else if (!strcmp(arg, "-R"))
1409                 options->reverse_diff = 1;
1410         else if (!strncmp(arg, "-S", 2))
1411                 options->pickaxe = arg + 2;
1412         else if (!strcmp(arg, "-s"))
1413                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
1414         else if (!strncmp(arg, "-O", 2))
1415                 options->orderfile = arg + 2;
1416         else if (!strncmp(arg, "--diff-filter=", 14))
1417                 options->filter = arg + 14;
1418         else if (!strcmp(arg, "--pickaxe-all"))
1419                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
1420         else if (!strcmp(arg, "--pickaxe-regex"))
1421                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1422         else if (!strncmp(arg, "-B", 2)) {
1423                 if ((options->break_opt =
1424                      diff_scoreopt_parse(arg)) == -1)
1425                         return -1;
1426         }
1427         else if (!strncmp(arg, "-M", 2)) {
1428                 if ((options->rename_score =
1429                      diff_scoreopt_parse(arg)) == -1)
1430                         return -1;
1431                 options->detect_rename = DIFF_DETECT_RENAME;
1432         }
1433         else if (!strncmp(arg, "-C", 2)) {
1434                 if ((options->rename_score =
1435                      diff_scoreopt_parse(arg)) == -1)
1436                         return -1;
1437                 options->detect_rename = DIFF_DETECT_COPY;
1438         }
1439         else if (!strcmp(arg, "--find-copies-harder"))
1440                 options->find_copies_harder = 1;
1441         else if (!strcmp(arg, "--abbrev"))
1442                 options->abbrev = DEFAULT_ABBREV;
1443         else if (!strncmp(arg, "--abbrev=", 9)) {
1444                 options->abbrev = strtoul(arg + 9, NULL, 10);
1445                 if (options->abbrev < MINIMUM_ABBREV)
1446                         options->abbrev = MINIMUM_ABBREV;
1447                 else if (40 < options->abbrev)
1448                         options->abbrev = 40;
1449         }
1450         else
1451                 return 0;
1452         return 1;
1453 }
1454
1455 static int parse_num(const char **cp_p)
1456 {
1457         unsigned long num, scale;
1458         int ch, dot;
1459         const char *cp = *cp_p;
1460
1461         num = 0;
1462         scale = 1;
1463         dot = 0;
1464         for(;;) {
1465                 ch = *cp;
1466                 if ( !dot && ch == '.' ) {
1467                         scale = 1;
1468                         dot = 1;
1469                 } else if ( ch == '%' ) {
1470                         scale = dot ? scale*100 : 100;
1471                         cp++;   /* % is always at the end */
1472                         break;
1473                 } else if ( ch >= '0' && ch <= '9' ) {
1474                         if ( scale < 100000 ) {
1475                                 scale *= 10;
1476                                 num = (num*10) + (ch-'0');
1477                         }
1478                 } else {
1479                         break;
1480                 }
1481                 cp++;
1482         }
1483         *cp_p = cp;
1484
1485         /* user says num divided by scale and we say internally that
1486          * is MAX_SCORE * num / scale.
1487          */
1488         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
1489 }
1490
1491 int diff_scoreopt_parse(const char *opt)
1492 {
1493         int opt1, opt2, cmd;
1494
1495         if (*opt++ != '-')
1496                 return -1;
1497         cmd = *opt++;
1498         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
1499                 return -1; /* that is not a -M, -C nor -B option */
1500
1501         opt1 = parse_num(&opt);
1502         if (cmd != 'B')
1503                 opt2 = 0;
1504         else {
1505                 if (*opt == 0)
1506                         opt2 = 0;
1507                 else if (*opt != '/')
1508                         return -1; /* we expect -B80/99 or -B80 */
1509                 else {
1510                         opt++;
1511                         opt2 = parse_num(&opt);
1512                 }
1513         }
1514         if (*opt != 0)
1515                 return -1;
1516         return opt1 | (opt2 << 16);
1517 }
1518
1519 struct diff_queue_struct diff_queued_diff;
1520
1521 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
1522 {
1523         if (queue->alloc <= queue->nr) {
1524                 queue->alloc = alloc_nr(queue->alloc);
1525                 queue->queue = xrealloc(queue->queue,
1526                                         sizeof(dp) * queue->alloc);
1527         }
1528         queue->queue[queue->nr++] = dp;
1529 }
1530
1531 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
1532                                  struct diff_filespec *one,
1533                                  struct diff_filespec *two)
1534 {
1535         struct diff_filepair *dp = xmalloc(sizeof(*dp));
1536         dp->one = one;
1537         dp->two = two;
1538         dp->score = 0;
1539         dp->status = 0;
1540         dp->source_stays = 0;
1541         dp->broken_pair = 0;
1542         if (queue)
1543                 diff_q(queue, dp);
1544         return dp;
1545 }
1546
1547 void diff_free_filepair(struct diff_filepair *p)
1548 {
1549         diff_free_filespec_data(p->one);
1550         diff_free_filespec_data(p->two);
1551         free(p->one);
1552         free(p->two);
1553         free(p);
1554 }
1555
1556 /* This is different from find_unique_abbrev() in that
1557  * it stuffs the result with dots for alignment.
1558  */
1559 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
1560 {
1561         int abblen;
1562         const char *abbrev;
1563         if (len == 40)
1564                 return sha1_to_hex(sha1);
1565
1566         abbrev = find_unique_abbrev(sha1, len);
1567         if (!abbrev)
1568                 return sha1_to_hex(sha1);
1569         abblen = strlen(abbrev);
1570         if (abblen < 37) {
1571                 static char hex[41];
1572                 if (len < abblen && abblen <= len + 2)
1573                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
1574                 else
1575                         sprintf(hex, "%s...", abbrev);
1576                 return hex;
1577         }
1578         return sha1_to_hex(sha1);
1579 }
1580
1581 static void diff_flush_raw(struct diff_filepair *p,
1582                            int line_termination,
1583                            int inter_name_termination,
1584                            struct diff_options *options,
1585                            int output_format)
1586 {
1587         int two_paths;
1588         char status[10];
1589         int abbrev = options->abbrev;
1590         const char *path_one, *path_two;
1591
1592         path_one = p->one->path;
1593         path_two = p->two->path;
1594         if (line_termination) {
1595                 path_one = quote_one(path_one);
1596                 path_two = quote_one(path_two);
1597         }
1598
1599         if (p->score)
1600                 sprintf(status, "%c%03d", p->status,
1601                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
1602         else {
1603                 status[0] = p->status;
1604                 status[1] = 0;
1605         }
1606         switch (p->status) {
1607         case DIFF_STATUS_COPIED:
1608         case DIFF_STATUS_RENAMED:
1609                 two_paths = 1;
1610                 break;
1611         case DIFF_STATUS_ADDED:
1612         case DIFF_STATUS_DELETED:
1613                 two_paths = 0;
1614                 break;
1615         default:
1616                 two_paths = 0;
1617                 break;
1618         }
1619         if (output_format != DIFF_FORMAT_NAME_STATUS) {
1620                 printf(":%06o %06o %s ",
1621                        p->one->mode, p->two->mode,
1622                        diff_unique_abbrev(p->one->sha1, abbrev));
1623                 printf("%s ",
1624                        diff_unique_abbrev(p->two->sha1, abbrev));
1625         }
1626         printf("%s%c%s", status, inter_name_termination, path_one);
1627         if (two_paths)
1628                 printf("%c%s", inter_name_termination, path_two);
1629         putchar(line_termination);
1630         if (path_one != p->one->path)
1631                 free((void*)path_one);
1632         if (path_two != p->two->path)
1633                 free((void*)path_two);
1634 }
1635
1636 static void diff_flush_name(struct diff_filepair *p,
1637                             int inter_name_termination,
1638                             int line_termination)
1639 {
1640         char *path = p->two->path;
1641
1642         if (line_termination)
1643                 path = quote_one(p->two->path);
1644         else
1645                 path = p->two->path;
1646         printf("%s%c", path, line_termination);
1647         if (p->two->path != path)
1648                 free(path);
1649 }
1650
1651 int diff_unmodified_pair(struct diff_filepair *p)
1652 {
1653         /* This function is written stricter than necessary to support
1654          * the currently implemented transformers, but the idea is to
1655          * let transformers to produce diff_filepairs any way they want,
1656          * and filter and clean them up here before producing the output.
1657          */
1658         struct diff_filespec *one, *two;
1659
1660         if (DIFF_PAIR_UNMERGED(p))
1661                 return 0; /* unmerged is interesting */
1662
1663         one = p->one;
1664         two = p->two;
1665
1666         /* deletion, addition, mode or type change
1667          * and rename are all interesting.
1668          */
1669         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
1670             DIFF_PAIR_MODE_CHANGED(p) ||
1671             strcmp(one->path, two->path))
1672                 return 0;
1673
1674         /* both are valid and point at the same path.  that is, we are
1675          * dealing with a change.
1676          */
1677         if (one->sha1_valid && two->sha1_valid &&
1678             !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
1679                 return 1; /* no change */
1680         if (!one->sha1_valid && !two->sha1_valid)
1681                 return 1; /* both look at the same file on the filesystem. */
1682         return 0;
1683 }
1684
1685 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
1686 {
1687         if (diff_unmodified_pair(p))
1688                 return;
1689
1690         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1691             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1692                 return; /* no tree diffs in patch format */
1693
1694         run_diff(p, o);
1695 }
1696
1697 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
1698                             struct diffstat_t *diffstat)
1699 {
1700         if (diff_unmodified_pair(p))
1701                 return;
1702
1703         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1704             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1705                 return; /* no tree diffs in patch format */
1706
1707         run_diffstat(p, o, diffstat);
1708 }
1709
1710 static void diff_flush_checkdiff(struct diff_filepair *p,
1711                 struct diff_options *o)
1712 {
1713         if (diff_unmodified_pair(p))
1714                 return;
1715
1716         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1717             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1718                 return; /* no tree diffs in patch format */
1719
1720         run_checkdiff(p, o);
1721 }
1722
1723 int diff_queue_is_empty(void)
1724 {
1725         struct diff_queue_struct *q = &diff_queued_diff;
1726         int i;
1727         for (i = 0; i < q->nr; i++)
1728                 if (!diff_unmodified_pair(q->queue[i]))
1729                         return 0;
1730         return 1;
1731 }
1732
1733 #if DIFF_DEBUG
1734 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
1735 {
1736         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
1737                 x, one ? one : "",
1738                 s->path,
1739                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
1740                 s->mode,
1741                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
1742         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
1743                 x, one ? one : "",
1744                 s->size, s->xfrm_flags);
1745 }
1746
1747 void diff_debug_filepair(const struct diff_filepair *p, int i)
1748 {
1749         diff_debug_filespec(p->one, i, "one");
1750         diff_debug_filespec(p->two, i, "two");
1751         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
1752                 p->score, p->status ? p->status : '?',
1753                 p->source_stays, p->broken_pair);
1754 }
1755
1756 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
1757 {
1758         int i;
1759         if (msg)
1760                 fprintf(stderr, "%s\n", msg);
1761         fprintf(stderr, "q->nr = %d\n", q->nr);
1762         for (i = 0; i < q->nr; i++) {
1763                 struct diff_filepair *p = q->queue[i];
1764                 diff_debug_filepair(p, i);
1765         }
1766 }
1767 #endif
1768
1769 static void diff_resolve_rename_copy(void)
1770 {
1771         int i, j;
1772         struct diff_filepair *p, *pp;
1773         struct diff_queue_struct *q = &diff_queued_diff;
1774
1775         diff_debug_queue("resolve-rename-copy", q);
1776
1777         for (i = 0; i < q->nr; i++) {
1778                 p = q->queue[i];
1779                 p->status = 0; /* undecided */
1780                 if (DIFF_PAIR_UNMERGED(p))
1781                         p->status = DIFF_STATUS_UNMERGED;
1782                 else if (!DIFF_FILE_VALID(p->one))
1783                         p->status = DIFF_STATUS_ADDED;
1784                 else if (!DIFF_FILE_VALID(p->two))
1785                         p->status = DIFF_STATUS_DELETED;
1786                 else if (DIFF_PAIR_TYPE_CHANGED(p))
1787                         p->status = DIFF_STATUS_TYPE_CHANGED;
1788
1789                 /* from this point on, we are dealing with a pair
1790                  * whose both sides are valid and of the same type, i.e.
1791                  * either in-place edit or rename/copy edit.
1792                  */
1793                 else if (DIFF_PAIR_RENAME(p)) {
1794                         if (p->source_stays) {
1795                                 p->status = DIFF_STATUS_COPIED;
1796                                 continue;
1797                         }
1798                         /* See if there is some other filepair that
1799                          * copies from the same source as us.  If so
1800                          * we are a copy.  Otherwise we are either a
1801                          * copy if the path stays, or a rename if it
1802                          * does not, but we already handled "stays" case.
1803                          */
1804                         for (j = i + 1; j < q->nr; j++) {
1805                                 pp = q->queue[j];
1806                                 if (strcmp(pp->one->path, p->one->path))
1807                                         continue; /* not us */
1808                                 if (!DIFF_PAIR_RENAME(pp))
1809                                         continue; /* not a rename/copy */
1810                                 /* pp is a rename/copy from the same source */
1811                                 p->status = DIFF_STATUS_COPIED;
1812                                 break;
1813                         }
1814                         if (!p->status)
1815                                 p->status = DIFF_STATUS_RENAMED;
1816                 }
1817                 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
1818                          p->one->mode != p->two->mode)
1819                         p->status = DIFF_STATUS_MODIFIED;
1820                 else {
1821                         /* This is a "no-change" entry and should not
1822                          * happen anymore, but prepare for broken callers.
1823                          */
1824                         error("feeding unmodified %s to diffcore",
1825                               p->one->path);
1826                         p->status = DIFF_STATUS_UNKNOWN;
1827                 }
1828         }
1829         diff_debug_queue("resolve-rename-copy done", q);
1830 }
1831
1832 static void flush_one_pair(struct diff_filepair *p,
1833                            int diff_output_format,
1834                            struct diff_options *options,
1835                            struct diffstat_t *diffstat)
1836 {
1837         int inter_name_termination = '\t';
1838         int line_termination = options->line_termination;
1839         if (!line_termination)
1840                 inter_name_termination = 0;
1841
1842         switch (p->status) {
1843         case DIFF_STATUS_UNKNOWN:
1844                 break;
1845         case 0:
1846                 die("internal error in diff-resolve-rename-copy");
1847                 break;
1848         default:
1849                 switch (diff_output_format) {
1850                 case DIFF_FORMAT_DIFFSTAT:
1851                         diff_flush_stat(p, options, diffstat);
1852                         break;
1853                 case DIFF_FORMAT_CHECKDIFF:
1854                         diff_flush_checkdiff(p, options);
1855                         break;
1856                 case DIFF_FORMAT_PATCH:
1857                         diff_flush_patch(p, options);
1858                         break;
1859                 case DIFF_FORMAT_RAW:
1860                 case DIFF_FORMAT_NAME_STATUS:
1861                         diff_flush_raw(p, line_termination,
1862                                        inter_name_termination,
1863                                        options, diff_output_format);
1864                         break;
1865                 case DIFF_FORMAT_NAME:
1866                         diff_flush_name(p,
1867                                         inter_name_termination,
1868                                         line_termination);
1869                         break;
1870                 case DIFF_FORMAT_NO_OUTPUT:
1871                         break;
1872                 }
1873         }
1874 }
1875
1876 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
1877 {
1878         if (fs->mode)
1879                 printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
1880         else
1881                 printf(" %s %s\n", newdelete, fs->path);
1882 }
1883
1884
1885 static void show_mode_change(struct diff_filepair *p, int show_name)
1886 {
1887         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
1888                 if (show_name)
1889                         printf(" mode change %06o => %06o %s\n",
1890                                p->one->mode, p->two->mode, p->two->path);
1891                 else
1892                         printf(" mode change %06o => %06o\n",
1893                                p->one->mode, p->two->mode);
1894         }
1895 }
1896
1897 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
1898 {
1899         const char *old, *new;
1900
1901         /* Find common prefix */
1902         old = p->one->path;
1903         new = p->two->path;
1904         while (1) {
1905                 const char *slash_old, *slash_new;
1906                 slash_old = strchr(old, '/');
1907                 slash_new = strchr(new, '/');
1908                 if (!slash_old ||
1909                     !slash_new ||
1910                     slash_old - old != slash_new - new ||
1911                     memcmp(old, new, slash_new - new))
1912                         break;
1913                 old = slash_old + 1;
1914                 new = slash_new + 1;
1915         }
1916         /* p->one->path thru old is the common prefix, and old and new
1917          * through the end of names are renames
1918          */
1919         if (old != p->one->path)
1920                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
1921                        (int)(old - p->one->path), p->one->path,
1922                        old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
1923         else
1924                 printf(" %s %s => %s (%d%%)\n", renamecopy,
1925                        p->one->path, p->two->path,
1926                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
1927         show_mode_change(p, 0);
1928 }
1929
1930 static void diff_summary(struct diff_filepair *p)
1931 {
1932         switch(p->status) {
1933         case DIFF_STATUS_DELETED:
1934                 show_file_mode_name("delete", p->one);
1935                 break;
1936         case DIFF_STATUS_ADDED:
1937                 show_file_mode_name("create", p->two);
1938                 break;
1939         case DIFF_STATUS_COPIED:
1940                 show_rename_copy("copy", p);
1941                 break;
1942         case DIFF_STATUS_RENAMED:
1943                 show_rename_copy("rename", p);
1944                 break;
1945         default:
1946                 if (p->score) {
1947                         printf(" rewrite %s (%d%%)\n", p->two->path,
1948                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
1949                         show_mode_change(p, 0);
1950                 } else  show_mode_change(p, 1);
1951                 break;
1952         }
1953 }
1954
1955 void diff_flush(struct diff_options *options)
1956 {
1957         struct diff_queue_struct *q = &diff_queued_diff;
1958         int i;
1959         int diff_output_format = options->output_format;
1960         struct diffstat_t *diffstat = NULL;
1961
1962         if (diff_output_format == DIFF_FORMAT_DIFFSTAT || options->with_stat) {
1963                 diffstat = xcalloc(sizeof (struct diffstat_t), 1);
1964                 diffstat->xm.consume = diffstat_consume;
1965         }
1966
1967         if (options->with_raw) {
1968                 for (i = 0; i < q->nr; i++) {
1969                         struct diff_filepair *p = q->queue[i];
1970                         flush_one_pair(p, DIFF_FORMAT_RAW, options, NULL);
1971                 }
1972                 putchar(options->line_termination);
1973         }
1974         if (options->with_stat) {
1975                 for (i = 0; i < q->nr; i++) {
1976                         struct diff_filepair *p = q->queue[i];
1977                         flush_one_pair(p, DIFF_FORMAT_DIFFSTAT, options,
1978                                        diffstat);
1979                 }
1980                 show_stats(diffstat);
1981                 free(diffstat);
1982                 diffstat = NULL;
1983                 putchar(options->line_termination);
1984         }
1985         for (i = 0; i < q->nr; i++) {
1986                 struct diff_filepair *p = q->queue[i];
1987                 flush_one_pair(p, diff_output_format, options, diffstat);
1988         }
1989
1990         if (diffstat) {
1991                 show_stats(diffstat);
1992                 free(diffstat);
1993         }
1994
1995         for (i = 0; i < q->nr; i++) {
1996                 if (options->summary)
1997                         diff_summary(q->queue[i]);
1998                 diff_free_filepair(q->queue[i]);
1999         }
2000
2001         free(q->queue);
2002         q->queue = NULL;
2003         q->nr = q->alloc = 0;
2004 }
2005
2006 static void diffcore_apply_filter(const char *filter)
2007 {
2008         int i;
2009         struct diff_queue_struct *q = &diff_queued_diff;
2010         struct diff_queue_struct outq;
2011         outq.queue = NULL;
2012         outq.nr = outq.alloc = 0;
2013
2014         if (!filter)
2015                 return;
2016
2017         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2018                 int found;
2019                 for (i = found = 0; !found && i < q->nr; i++) {
2020                         struct diff_filepair *p = q->queue[i];
2021                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2022                              ((p->score &&
2023                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2024                               (!p->score &&
2025                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2026                             ((p->status != DIFF_STATUS_MODIFIED) &&
2027                              strchr(filter, p->status)))
2028                                 found++;
2029                 }
2030                 if (found)
2031                         return;
2032
2033                 /* otherwise we will clear the whole queue
2034                  * by copying the empty outq at the end of this
2035                  * function, but first clear the current entries
2036                  * in the queue.
2037                  */
2038                 for (i = 0; i < q->nr; i++)
2039                         diff_free_filepair(q->queue[i]);
2040         }
2041         else {
2042                 /* Only the matching ones */
2043                 for (i = 0; i < q->nr; i++) {
2044                         struct diff_filepair *p = q->queue[i];
2045
2046                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2047                              ((p->score &&
2048                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2049                               (!p->score &&
2050                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2051                             ((p->status != DIFF_STATUS_MODIFIED) &&
2052                              strchr(filter, p->status)))
2053                                 diff_q(&outq, p);
2054                         else
2055                                 diff_free_filepair(p);
2056                 }
2057         }
2058         free(q->queue);
2059         *q = outq;
2060 }
2061
2062 void diffcore_std(struct diff_options *options)
2063 {
2064         if (options->break_opt != -1)
2065                 diffcore_break(options->break_opt);
2066         if (options->detect_rename)
2067                 diffcore_rename(options);
2068         if (options->break_opt != -1)
2069                 diffcore_merge_broken();
2070         if (options->pickaxe)
2071                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2072         if (options->orderfile)
2073                 diffcore_order(options->orderfile);
2074         diff_resolve_rename_copy();
2075         diffcore_apply_filter(options->filter);
2076 }
2077
2078
2079 void diffcore_std_no_resolve(struct diff_options *options)
2080 {
2081         if (options->pickaxe)
2082                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2083         if (options->orderfile)
2084                 diffcore_order(options->orderfile);
2085         diffcore_apply_filter(options->filter);
2086 }
2087
2088 void diff_addremove(struct diff_options *options,
2089                     int addremove, unsigned mode,
2090                     const unsigned char *sha1,
2091                     const char *base, const char *path)
2092 {
2093         char concatpath[PATH_MAX];
2094         struct diff_filespec *one, *two;
2095
2096         /* This may look odd, but it is a preparation for
2097          * feeding "there are unchanged files which should
2098          * not produce diffs, but when you are doing copy
2099          * detection you would need them, so here they are"
2100          * entries to the diff-core.  They will be prefixed
2101          * with something like '=' or '*' (I haven't decided
2102          * which but should not make any difference).
2103          * Feeding the same new and old to diff_change()
2104          * also has the same effect.
2105          * Before the final output happens, they are pruned after
2106          * merged into rename/copy pairs as appropriate.
2107          */
2108         if (options->reverse_diff)
2109                 addremove = (addremove == '+' ? '-' :
2110                              addremove == '-' ? '+' : addremove);
2111
2112         if (!path) path = "";
2113         sprintf(concatpath, "%s%s", base, path);
2114         one = alloc_filespec(concatpath);
2115         two = alloc_filespec(concatpath);
2116
2117         if (addremove != '+')
2118                 fill_filespec(one, sha1, mode);
2119         if (addremove != '-')
2120                 fill_filespec(two, sha1, mode);
2121
2122         diff_queue(&diff_queued_diff, one, two);
2123 }
2124
2125 void diff_change(struct diff_options *options,
2126                  unsigned old_mode, unsigned new_mode,
2127                  const unsigned char *old_sha1,
2128                  const unsigned char *new_sha1,
2129                  const char *base, const char *path)
2130 {
2131         char concatpath[PATH_MAX];
2132         struct diff_filespec *one, *two;
2133
2134         if (options->reverse_diff) {
2135                 unsigned tmp;
2136                 const unsigned char *tmp_c;
2137                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2138                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2139         }
2140         if (!path) path = "";
2141         sprintf(concatpath, "%s%s", base, path);
2142         one = alloc_filespec(concatpath);
2143         two = alloc_filespec(concatpath);
2144         fill_filespec(one, old_sha1, old_mode);
2145         fill_filespec(two, new_sha1, new_mode);
2146
2147         diff_queue(&diff_queued_diff, one, two);
2148 }
2149
2150 void diff_unmerge(struct diff_options *options,
2151                   const char *path)
2152 {
2153         struct diff_filespec *one, *two;
2154         one = alloc_filespec(path);
2155         two = alloc_filespec(path);
2156         diff_queue(&diff_queued_diff, one, two);
2157 }