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(pfx_length + a_midlen + b_midlen + 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, NULL, 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         /*
1307          * These combinations do not make sense.
1308          */
1309         if (options->output_format == DIFF_FORMAT_RAW)
1310                 options->with_raw = 0;
1311         if (options->output_format == DIFF_FORMAT_DIFFSTAT)
1312                 options->with_stat  = 0;
1313
1314         if (options->detect_rename && options->rename_limit < 0)
1315                 options->rename_limit = diff_rename_limit_default;
1316         if (options->setup & DIFF_SETUP_USE_CACHE) {
1317                 if (!active_cache)
1318                         /* read-cache does not die even when it fails
1319                          * so it is safe for us to do this here.  Also
1320                          * it does not smudge active_cache or active_nr
1321                          * when it fails, so we do not have to worry about
1322                          * cleaning it up ourselves either.
1323                          */
1324                         read_cache();
1325         }
1326         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1327                 use_size_cache = 1;
1328         if (options->abbrev <= 0 || 40 < options->abbrev)
1329                 options->abbrev = 40; /* full */
1330
1331         return 0;
1332 }
1333
1334 int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1335 {
1336         char c, *eq;
1337         int len;
1338
1339         if (*arg != '-')
1340                 return 0;
1341         c = *++arg;
1342         if (!c)
1343                 return 0;
1344         if (c == arg_short) {
1345                 c = *++arg;
1346                 if (!c)
1347                         return 1;
1348                 if (val && isdigit(c)) {
1349                         char *end;
1350                         int n = strtoul(arg, &end, 10);
1351                         if (*end)
1352                                 return 0;
1353                         *val = n;
1354                         return 1;
1355                 }
1356                 return 0;
1357         }
1358         if (c != '-')
1359                 return 0;
1360         arg++;
1361         eq = strchr(arg, '=');
1362         if (eq)
1363                 len = eq - arg;
1364         else
1365                 len = strlen(arg);
1366         if (!len || strncmp(arg, arg_long, len))
1367                 return 0;
1368         if (eq) {
1369                 int n;
1370                 char *end;
1371                 if (!isdigit(*++eq))
1372                         return 0;
1373                 n = strtoul(eq, &end, 10);
1374                 if (*end)
1375                         return 0;
1376                 *val = n;
1377         }
1378         return 1;
1379 }
1380
1381 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1382 {
1383         const char *arg = av[0];
1384         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1385                 options->output_format = DIFF_FORMAT_PATCH;
1386         else if (opt_arg(arg, 'U', "unified", &options->context))
1387                 options->output_format = DIFF_FORMAT_PATCH;
1388         else if (!strcmp(arg, "--patch-with-raw")) {
1389                 options->output_format = DIFF_FORMAT_PATCH;
1390                 options->with_raw = 1;
1391         }
1392         else if (!strcmp(arg, "--stat"))
1393                 options->output_format = DIFF_FORMAT_DIFFSTAT;
1394         else if (!strcmp(arg, "--check"))
1395                 options->output_format = DIFF_FORMAT_CHECKDIFF;
1396         else if (!strcmp(arg, "--summary"))
1397                 options->summary = 1;
1398         else if (!strcmp(arg, "--patch-with-stat")) {
1399                 options->output_format = DIFF_FORMAT_PATCH;
1400                 options->with_stat = 1;
1401         }
1402         else if (!strcmp(arg, "-z"))
1403                 options->line_termination = 0;
1404         else if (!strncmp(arg, "-l", 2))
1405                 options->rename_limit = strtoul(arg+2, NULL, 10);
1406         else if (!strcmp(arg, "--full-index"))
1407                 options->full_index = 1;
1408         else if (!strcmp(arg, "--binary")) {
1409                 options->output_format = DIFF_FORMAT_PATCH;
1410                 options->full_index = options->binary = 1;
1411         }
1412         else if (!strcmp(arg, "--name-only"))
1413                 options->output_format = DIFF_FORMAT_NAME;
1414         else if (!strcmp(arg, "--name-status"))
1415                 options->output_format = DIFF_FORMAT_NAME_STATUS;
1416         else if (!strcmp(arg, "-R"))
1417                 options->reverse_diff = 1;
1418         else if (!strncmp(arg, "-S", 2))
1419                 options->pickaxe = arg + 2;
1420         else if (!strcmp(arg, "-s"))
1421                 options->output_format = DIFF_FORMAT_NO_OUTPUT;
1422         else if (!strncmp(arg, "-O", 2))
1423                 options->orderfile = arg + 2;
1424         else if (!strncmp(arg, "--diff-filter=", 14))
1425                 options->filter = arg + 14;
1426         else if (!strcmp(arg, "--pickaxe-all"))
1427                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
1428         else if (!strcmp(arg, "--pickaxe-regex"))
1429                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1430         else if (!strncmp(arg, "-B", 2)) {
1431                 if ((options->break_opt =
1432                      diff_scoreopt_parse(arg)) == -1)
1433                         return -1;
1434         }
1435         else if (!strncmp(arg, "-M", 2)) {
1436                 if ((options->rename_score =
1437                      diff_scoreopt_parse(arg)) == -1)
1438                         return -1;
1439                 options->detect_rename = DIFF_DETECT_RENAME;
1440         }
1441         else if (!strncmp(arg, "-C", 2)) {
1442                 if ((options->rename_score =
1443                      diff_scoreopt_parse(arg)) == -1)
1444                         return -1;
1445                 options->detect_rename = DIFF_DETECT_COPY;
1446         }
1447         else if (!strcmp(arg, "--find-copies-harder"))
1448                 options->find_copies_harder = 1;
1449         else if (!strcmp(arg, "--abbrev"))
1450                 options->abbrev = DEFAULT_ABBREV;
1451         else if (!strncmp(arg, "--abbrev=", 9)) {
1452                 options->abbrev = strtoul(arg + 9, NULL, 10);
1453                 if (options->abbrev < MINIMUM_ABBREV)
1454                         options->abbrev = MINIMUM_ABBREV;
1455                 else if (40 < options->abbrev)
1456                         options->abbrev = 40;
1457         }
1458         else
1459                 return 0;
1460         return 1;
1461 }
1462
1463 static int parse_num(const char **cp_p)
1464 {
1465         unsigned long num, scale;
1466         int ch, dot;
1467         const char *cp = *cp_p;
1468
1469         num = 0;
1470         scale = 1;
1471         dot = 0;
1472         for(;;) {
1473                 ch = *cp;
1474                 if ( !dot && ch == '.' ) {
1475                         scale = 1;
1476                         dot = 1;
1477                 } else if ( ch == '%' ) {
1478                         scale = dot ? scale*100 : 100;
1479                         cp++;   /* % is always at the end */
1480                         break;
1481                 } else if ( ch >= '0' && ch <= '9' ) {
1482                         if ( scale < 100000 ) {
1483                                 scale *= 10;
1484                                 num = (num*10) + (ch-'0');
1485                         }
1486                 } else {
1487                         break;
1488                 }
1489                 cp++;
1490         }
1491         *cp_p = cp;
1492
1493         /* user says num divided by scale and we say internally that
1494          * is MAX_SCORE * num / scale.
1495          */
1496         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
1497 }
1498
1499 int diff_scoreopt_parse(const char *opt)
1500 {
1501         int opt1, opt2, cmd;
1502
1503         if (*opt++ != '-')
1504                 return -1;
1505         cmd = *opt++;
1506         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
1507                 return -1; /* that is not a -M, -C nor -B option */
1508
1509         opt1 = parse_num(&opt);
1510         if (cmd != 'B')
1511                 opt2 = 0;
1512         else {
1513                 if (*opt == 0)
1514                         opt2 = 0;
1515                 else if (*opt != '/')
1516                         return -1; /* we expect -B80/99 or -B80 */
1517                 else {
1518                         opt++;
1519                         opt2 = parse_num(&opt);
1520                 }
1521         }
1522         if (*opt != 0)
1523                 return -1;
1524         return opt1 | (opt2 << 16);
1525 }
1526
1527 struct diff_queue_struct diff_queued_diff;
1528
1529 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
1530 {
1531         if (queue->alloc <= queue->nr) {
1532                 queue->alloc = alloc_nr(queue->alloc);
1533                 queue->queue = xrealloc(queue->queue,
1534                                         sizeof(dp) * queue->alloc);
1535         }
1536         queue->queue[queue->nr++] = dp;
1537 }
1538
1539 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
1540                                  struct diff_filespec *one,
1541                                  struct diff_filespec *two)
1542 {
1543         struct diff_filepair *dp = xmalloc(sizeof(*dp));
1544         dp->one = one;
1545         dp->two = two;
1546         dp->score = 0;
1547         dp->status = 0;
1548         dp->source_stays = 0;
1549         dp->broken_pair = 0;
1550         if (queue)
1551                 diff_q(queue, dp);
1552         return dp;
1553 }
1554
1555 void diff_free_filepair(struct diff_filepair *p)
1556 {
1557         diff_free_filespec_data(p->one);
1558         diff_free_filespec_data(p->two);
1559         free(p->one);
1560         free(p->two);
1561         free(p);
1562 }
1563
1564 /* This is different from find_unique_abbrev() in that
1565  * it stuffs the result with dots for alignment.
1566  */
1567 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
1568 {
1569         int abblen;
1570         const char *abbrev;
1571         if (len == 40)
1572                 return sha1_to_hex(sha1);
1573
1574         abbrev = find_unique_abbrev(sha1, len);
1575         if (!abbrev)
1576                 return sha1_to_hex(sha1);
1577         abblen = strlen(abbrev);
1578         if (abblen < 37) {
1579                 static char hex[41];
1580                 if (len < abblen && abblen <= len + 2)
1581                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
1582                 else
1583                         sprintf(hex, "%s...", abbrev);
1584                 return hex;
1585         }
1586         return sha1_to_hex(sha1);
1587 }
1588
1589 static void diff_flush_raw(struct diff_filepair *p,
1590                            int line_termination,
1591                            int inter_name_termination,
1592                            struct diff_options *options,
1593                            int output_format)
1594 {
1595         int two_paths;
1596         char status[10];
1597         int abbrev = options->abbrev;
1598         const char *path_one, *path_two;
1599
1600         path_one = p->one->path;
1601         path_two = p->two->path;
1602         if (line_termination) {
1603                 path_one = quote_one(path_one);
1604                 path_two = quote_one(path_two);
1605         }
1606
1607         if (p->score)
1608                 sprintf(status, "%c%03d", p->status,
1609                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
1610         else {
1611                 status[0] = p->status;
1612                 status[1] = 0;
1613         }
1614         switch (p->status) {
1615         case DIFF_STATUS_COPIED:
1616         case DIFF_STATUS_RENAMED:
1617                 two_paths = 1;
1618                 break;
1619         case DIFF_STATUS_ADDED:
1620         case DIFF_STATUS_DELETED:
1621                 two_paths = 0;
1622                 break;
1623         default:
1624                 two_paths = 0;
1625                 break;
1626         }
1627         if (output_format != DIFF_FORMAT_NAME_STATUS) {
1628                 printf(":%06o %06o %s ",
1629                        p->one->mode, p->two->mode,
1630                        diff_unique_abbrev(p->one->sha1, abbrev));
1631                 printf("%s ",
1632                        diff_unique_abbrev(p->two->sha1, abbrev));
1633         }
1634         printf("%s%c%s", status, inter_name_termination, path_one);
1635         if (two_paths)
1636                 printf("%c%s", inter_name_termination, path_two);
1637         putchar(line_termination);
1638         if (path_one != p->one->path)
1639                 free((void*)path_one);
1640         if (path_two != p->two->path)
1641                 free((void*)path_two);
1642 }
1643
1644 static void diff_flush_name(struct diff_filepair *p,
1645                             int inter_name_termination,
1646                             int line_termination)
1647 {
1648         char *path = p->two->path;
1649
1650         if (line_termination)
1651                 path = quote_one(p->two->path);
1652         else
1653                 path = p->two->path;
1654         printf("%s%c", path, line_termination);
1655         if (p->two->path != path)
1656                 free(path);
1657 }
1658
1659 int diff_unmodified_pair(struct diff_filepair *p)
1660 {
1661         /* This function is written stricter than necessary to support
1662          * the currently implemented transformers, but the idea is to
1663          * let transformers to produce diff_filepairs any way they want,
1664          * and filter and clean them up here before producing the output.
1665          */
1666         struct diff_filespec *one, *two;
1667
1668         if (DIFF_PAIR_UNMERGED(p))
1669                 return 0; /* unmerged is interesting */
1670
1671         one = p->one;
1672         two = p->two;
1673
1674         /* deletion, addition, mode or type change
1675          * and rename are all interesting.
1676          */
1677         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
1678             DIFF_PAIR_MODE_CHANGED(p) ||
1679             strcmp(one->path, two->path))
1680                 return 0;
1681
1682         /* both are valid and point at the same path.  that is, we are
1683          * dealing with a change.
1684          */
1685         if (one->sha1_valid && two->sha1_valid &&
1686             !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
1687                 return 1; /* no change */
1688         if (!one->sha1_valid && !two->sha1_valid)
1689                 return 1; /* both look at the same file on the filesystem. */
1690         return 0;
1691 }
1692
1693 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
1694 {
1695         if (diff_unmodified_pair(p))
1696                 return;
1697
1698         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1699             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1700                 return; /* no tree diffs in patch format */
1701
1702         run_diff(p, o);
1703 }
1704
1705 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
1706                             struct diffstat_t *diffstat)
1707 {
1708         if (diff_unmodified_pair(p))
1709                 return;
1710
1711         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1712             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1713                 return; /* no tree diffs in patch format */
1714
1715         run_diffstat(p, o, diffstat);
1716 }
1717
1718 static void diff_flush_checkdiff(struct diff_filepair *p,
1719                 struct diff_options *o)
1720 {
1721         if (diff_unmodified_pair(p))
1722                 return;
1723
1724         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
1725             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
1726                 return; /* no tree diffs in patch format */
1727
1728         run_checkdiff(p, o);
1729 }
1730
1731 int diff_queue_is_empty(void)
1732 {
1733         struct diff_queue_struct *q = &diff_queued_diff;
1734         int i;
1735         for (i = 0; i < q->nr; i++)
1736                 if (!diff_unmodified_pair(q->queue[i]))
1737                         return 0;
1738         return 1;
1739 }
1740
1741 #if DIFF_DEBUG
1742 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
1743 {
1744         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
1745                 x, one ? one : "",
1746                 s->path,
1747                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
1748                 s->mode,
1749                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
1750         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
1751                 x, one ? one : "",
1752                 s->size, s->xfrm_flags);
1753 }
1754
1755 void diff_debug_filepair(const struct diff_filepair *p, int i)
1756 {
1757         diff_debug_filespec(p->one, i, "one");
1758         diff_debug_filespec(p->two, i, "two");
1759         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
1760                 p->score, p->status ? p->status : '?',
1761                 p->source_stays, p->broken_pair);
1762 }
1763
1764 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
1765 {
1766         int i;
1767         if (msg)
1768                 fprintf(stderr, "%s\n", msg);
1769         fprintf(stderr, "q->nr = %d\n", q->nr);
1770         for (i = 0; i < q->nr; i++) {
1771                 struct diff_filepair *p = q->queue[i];
1772                 diff_debug_filepair(p, i);
1773         }
1774 }
1775 #endif
1776
1777 static void diff_resolve_rename_copy(void)
1778 {
1779         int i, j;
1780         struct diff_filepair *p, *pp;
1781         struct diff_queue_struct *q = &diff_queued_diff;
1782
1783         diff_debug_queue("resolve-rename-copy", q);
1784
1785         for (i = 0; i < q->nr; i++) {
1786                 p = q->queue[i];
1787                 p->status = 0; /* undecided */
1788                 if (DIFF_PAIR_UNMERGED(p))
1789                         p->status = DIFF_STATUS_UNMERGED;
1790                 else if (!DIFF_FILE_VALID(p->one))
1791                         p->status = DIFF_STATUS_ADDED;
1792                 else if (!DIFF_FILE_VALID(p->two))
1793                         p->status = DIFF_STATUS_DELETED;
1794                 else if (DIFF_PAIR_TYPE_CHANGED(p))
1795                         p->status = DIFF_STATUS_TYPE_CHANGED;
1796
1797                 /* from this point on, we are dealing with a pair
1798                  * whose both sides are valid and of the same type, i.e.
1799                  * either in-place edit or rename/copy edit.
1800                  */
1801                 else if (DIFF_PAIR_RENAME(p)) {
1802                         if (p->source_stays) {
1803                                 p->status = DIFF_STATUS_COPIED;
1804                                 continue;
1805                         }
1806                         /* See if there is some other filepair that
1807                          * copies from the same source as us.  If so
1808                          * we are a copy.  Otherwise we are either a
1809                          * copy if the path stays, or a rename if it
1810                          * does not, but we already handled "stays" case.
1811                          */
1812                         for (j = i + 1; j < q->nr; j++) {
1813                                 pp = q->queue[j];
1814                                 if (strcmp(pp->one->path, p->one->path))
1815                                         continue; /* not us */
1816                                 if (!DIFF_PAIR_RENAME(pp))
1817                                         continue; /* not a rename/copy */
1818                                 /* pp is a rename/copy from the same source */
1819                                 p->status = DIFF_STATUS_COPIED;
1820                                 break;
1821                         }
1822                         if (!p->status)
1823                                 p->status = DIFF_STATUS_RENAMED;
1824                 }
1825                 else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
1826                          p->one->mode != p->two->mode)
1827                         p->status = DIFF_STATUS_MODIFIED;
1828                 else {
1829                         /* This is a "no-change" entry and should not
1830                          * happen anymore, but prepare for broken callers.
1831                          */
1832                         error("feeding unmodified %s to diffcore",
1833                               p->one->path);
1834                         p->status = DIFF_STATUS_UNKNOWN;
1835                 }
1836         }
1837         diff_debug_queue("resolve-rename-copy done", q);
1838 }
1839
1840 static void flush_one_pair(struct diff_filepair *p,
1841                            int diff_output_format,
1842                            struct diff_options *options,
1843                            struct diffstat_t *diffstat)
1844 {
1845         int inter_name_termination = '\t';
1846         int line_termination = options->line_termination;
1847         if (!line_termination)
1848                 inter_name_termination = 0;
1849
1850         switch (p->status) {
1851         case DIFF_STATUS_UNKNOWN:
1852                 break;
1853         case 0:
1854                 die("internal error in diff-resolve-rename-copy");
1855                 break;
1856         default:
1857                 switch (diff_output_format) {
1858                 case DIFF_FORMAT_DIFFSTAT:
1859                         diff_flush_stat(p, options, diffstat);
1860                         break;
1861                 case DIFF_FORMAT_CHECKDIFF:
1862                         diff_flush_checkdiff(p, options);
1863                         break;
1864                 case DIFF_FORMAT_PATCH:
1865                         diff_flush_patch(p, options);
1866                         break;
1867                 case DIFF_FORMAT_RAW:
1868                 case DIFF_FORMAT_NAME_STATUS:
1869                         diff_flush_raw(p, line_termination,
1870                                        inter_name_termination,
1871                                        options, diff_output_format);
1872                         break;
1873                 case DIFF_FORMAT_NAME:
1874                         diff_flush_name(p,
1875                                         inter_name_termination,
1876                                         line_termination);
1877                         break;
1878                 case DIFF_FORMAT_NO_OUTPUT:
1879                         break;
1880                 }
1881         }
1882 }
1883
1884 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
1885 {
1886         if (fs->mode)
1887                 printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
1888         else
1889                 printf(" %s %s\n", newdelete, fs->path);
1890 }
1891
1892
1893 static void show_mode_change(struct diff_filepair *p, int show_name)
1894 {
1895         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
1896                 if (show_name)
1897                         printf(" mode change %06o => %06o %s\n",
1898                                p->one->mode, p->two->mode, p->two->path);
1899                 else
1900                         printf(" mode change %06o => %06o\n",
1901                                p->one->mode, p->two->mode);
1902         }
1903 }
1904
1905 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
1906 {
1907         const char *old, *new;
1908
1909         /* Find common prefix */
1910         old = p->one->path;
1911         new = p->two->path;
1912         while (1) {
1913                 const char *slash_old, *slash_new;
1914                 slash_old = strchr(old, '/');
1915                 slash_new = strchr(new, '/');
1916                 if (!slash_old ||
1917                     !slash_new ||
1918                     slash_old - old != slash_new - new ||
1919                     memcmp(old, new, slash_new - new))
1920                         break;
1921                 old = slash_old + 1;
1922                 new = slash_new + 1;
1923         }
1924         /* p->one->path thru old is the common prefix, and old and new
1925          * through the end of names are renames
1926          */
1927         if (old != p->one->path)
1928                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
1929                        (int)(old - p->one->path), p->one->path,
1930                        old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
1931         else
1932                 printf(" %s %s => %s (%d%%)\n", renamecopy,
1933                        p->one->path, p->two->path,
1934                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
1935         show_mode_change(p, 0);
1936 }
1937
1938 static void diff_summary(struct diff_filepair *p)
1939 {
1940         switch(p->status) {
1941         case DIFF_STATUS_DELETED:
1942                 show_file_mode_name("delete", p->one);
1943                 break;
1944         case DIFF_STATUS_ADDED:
1945                 show_file_mode_name("create", p->two);
1946                 break;
1947         case DIFF_STATUS_COPIED:
1948                 show_rename_copy("copy", p);
1949                 break;
1950         case DIFF_STATUS_RENAMED:
1951                 show_rename_copy("rename", p);
1952                 break;
1953         default:
1954                 if (p->score) {
1955                         printf(" rewrite %s (%d%%)\n", p->two->path,
1956                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
1957                         show_mode_change(p, 0);
1958                 } else  show_mode_change(p, 1);
1959                 break;
1960         }
1961 }
1962
1963 void diff_flush(struct diff_options *options)
1964 {
1965         struct diff_queue_struct *q = &diff_queued_diff;
1966         int i;
1967         int diff_output_format = options->output_format;
1968         struct diffstat_t *diffstat = NULL;
1969
1970         if (diff_output_format == DIFF_FORMAT_DIFFSTAT || options->with_stat) {
1971                 diffstat = xcalloc(sizeof (struct diffstat_t), 1);
1972                 diffstat->xm.consume = diffstat_consume;
1973         }
1974
1975         if (options->with_raw) {
1976                 for (i = 0; i < q->nr; i++) {
1977                         struct diff_filepair *p = q->queue[i];
1978                         flush_one_pair(p, DIFF_FORMAT_RAW, options, NULL);
1979                 }
1980                 putchar(options->line_termination);
1981         }
1982         if (options->with_stat) {
1983                 for (i = 0; i < q->nr; i++) {
1984                         struct diff_filepair *p = q->queue[i];
1985                         flush_one_pair(p, DIFF_FORMAT_DIFFSTAT, options,
1986                                        diffstat);
1987                 }
1988                 show_stats(diffstat);
1989                 free(diffstat);
1990                 diffstat = NULL;
1991                 if (options->summary)
1992                         for (i = 0; i < q->nr; i++)
1993                                 diff_summary(q->queue[i]);
1994                 putchar(options->line_termination);
1995         }
1996         for (i = 0; i < q->nr; i++) {
1997                 struct diff_filepair *p = q->queue[i];
1998                 flush_one_pair(p, diff_output_format, options, diffstat);
1999         }
2000
2001         if (diffstat) {
2002                 show_stats(diffstat);
2003                 free(diffstat);
2004         }
2005
2006         for (i = 0; i < q->nr; i++) {
2007                 if (diffstat && options->summary)
2008                         diff_summary(q->queue[i]);
2009                 diff_free_filepair(q->queue[i]);
2010         }
2011
2012         free(q->queue);
2013         q->queue = NULL;
2014         q->nr = q->alloc = 0;
2015 }
2016
2017 static void diffcore_apply_filter(const char *filter)
2018 {
2019         int i;
2020         struct diff_queue_struct *q = &diff_queued_diff;
2021         struct diff_queue_struct outq;
2022         outq.queue = NULL;
2023         outq.nr = outq.alloc = 0;
2024
2025         if (!filter)
2026                 return;
2027
2028         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2029                 int found;
2030                 for (i = found = 0; !found && i < q->nr; i++) {
2031                         struct diff_filepair *p = q->queue[i];
2032                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2033                              ((p->score &&
2034                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2035                               (!p->score &&
2036                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2037                             ((p->status != DIFF_STATUS_MODIFIED) &&
2038                              strchr(filter, p->status)))
2039                                 found++;
2040                 }
2041                 if (found)
2042                         return;
2043
2044                 /* otherwise we will clear the whole queue
2045                  * by copying the empty outq at the end of this
2046                  * function, but first clear the current entries
2047                  * in the queue.
2048                  */
2049                 for (i = 0; i < q->nr; i++)
2050                         diff_free_filepair(q->queue[i]);
2051         }
2052         else {
2053                 /* Only the matching ones */
2054                 for (i = 0; i < q->nr; i++) {
2055                         struct diff_filepair *p = q->queue[i];
2056
2057                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2058                              ((p->score &&
2059                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2060                               (!p->score &&
2061                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2062                             ((p->status != DIFF_STATUS_MODIFIED) &&
2063                              strchr(filter, p->status)))
2064                                 diff_q(&outq, p);
2065                         else
2066                                 diff_free_filepair(p);
2067                 }
2068         }
2069         free(q->queue);
2070         *q = outq;
2071 }
2072
2073 void diffcore_std(struct diff_options *options)
2074 {
2075         if (options->break_opt != -1)
2076                 diffcore_break(options->break_opt);
2077         if (options->detect_rename)
2078                 diffcore_rename(options);
2079         if (options->break_opt != -1)
2080                 diffcore_merge_broken();
2081         if (options->pickaxe)
2082                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2083         if (options->orderfile)
2084                 diffcore_order(options->orderfile);
2085         diff_resolve_rename_copy();
2086         diffcore_apply_filter(options->filter);
2087 }
2088
2089
2090 void diffcore_std_no_resolve(struct diff_options *options)
2091 {
2092         if (options->pickaxe)
2093                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2094         if (options->orderfile)
2095                 diffcore_order(options->orderfile);
2096         diffcore_apply_filter(options->filter);
2097 }
2098
2099 void diff_addremove(struct diff_options *options,
2100                     int addremove, unsigned mode,
2101                     const unsigned char *sha1,
2102                     const char *base, const char *path)
2103 {
2104         char concatpath[PATH_MAX];
2105         struct diff_filespec *one, *two;
2106
2107         /* This may look odd, but it is a preparation for
2108          * feeding "there are unchanged files which should
2109          * not produce diffs, but when you are doing copy
2110          * detection you would need them, so here they are"
2111          * entries to the diff-core.  They will be prefixed
2112          * with something like '=' or '*' (I haven't decided
2113          * which but should not make any difference).
2114          * Feeding the same new and old to diff_change()
2115          * also has the same effect.
2116          * Before the final output happens, they are pruned after
2117          * merged into rename/copy pairs as appropriate.
2118          */
2119         if (options->reverse_diff)
2120                 addremove = (addremove == '+' ? '-' :
2121                              addremove == '-' ? '+' : addremove);
2122
2123         if (!path) path = "";
2124         sprintf(concatpath, "%s%s", base, path);
2125         one = alloc_filespec(concatpath);
2126         two = alloc_filespec(concatpath);
2127
2128         if (addremove != '+')
2129                 fill_filespec(one, sha1, mode);
2130         if (addremove != '-')
2131                 fill_filespec(two, sha1, mode);
2132
2133         diff_queue(&diff_queued_diff, one, two);
2134 }
2135
2136 void diff_change(struct diff_options *options,
2137                  unsigned old_mode, unsigned new_mode,
2138                  const unsigned char *old_sha1,
2139                  const unsigned char *new_sha1,
2140                  const char *base, const char *path)
2141 {
2142         char concatpath[PATH_MAX];
2143         struct diff_filespec *one, *two;
2144
2145         if (options->reverse_diff) {
2146                 unsigned tmp;
2147                 const unsigned char *tmp_c;
2148                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2149                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2150         }
2151         if (!path) path = "";
2152         sprintf(concatpath, "%s%s", base, path);
2153         one = alloc_filespec(concatpath);
2154         two = alloc_filespec(concatpath);
2155         fill_filespec(one, old_sha1, old_mode);
2156         fill_filespec(two, new_sha1, new_mode);
2157
2158         diff_queue(&diff_queued_diff, one, two);
2159 }
2160
2161 void diff_unmerge(struct diff_options *options,
2162                   const char *path)
2163 {
2164         struct diff_filespec *one, *two;
2165         one = alloc_filespec(path);
2166         two = alloc_filespec(path);
2167         diff_queue(&diff_queued_diff, one, two);
2168 }