git.oblomov.eu Git - git/blob - combine-diff.c

   1 #include "cache.h"
   2 #include "commit.h"
   3 #include "blob.h"
   4 #include "diff.h"
   5 #include "diffcore.h"
   6 #include "quote.h"
   7 #include "xdiff-interface.h"
   8 #include "xdiff/xmacros.h"
   9 #include "log-tree.h"
  10 #include "refs.h"
  11 #include "userdiff.h"
  12 #include "sha1-array.h"
  13 #include "revision.h"
  14
  15 static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
  16 {
  17         struct diff_queue_struct *q = &diff_queued_diff;
  18         struct combine_diff_path *p;
  19         int i;
  20
  21         if (!n) {
  22                 struct combine_diff_path *list = NULL, **tail = &list;
  23                 for (i = 0; i < q->nr; i++) {
  24                         int len;
  25                         const char *path;
  26                         if (diff_unmodified_pair(q->queue[i]))
  27                                 continue;
  28                         path = q->queue[i]->two->path;
  29                         len = strlen(path);
  30                         p = xmalloc(combine_diff_path_size(num_parent, len));
  31                         p->path = (char *) &(p->parent[num_parent]);
  32                         memcpy(p->path, path, len);
  33                         p->path[len] = 0;
  34                         p->len = len;
  35                         p->next = NULL;
  36                         memset(p->parent, 0,
  37                                sizeof(p->parent[0]) * num_parent);
  38
  39                         hashcpy(p->sha1, q->queue[i]->two->sha1);
  40                         p->mode = q->queue[i]->two->mode;
  41                         hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
  42                         p->parent[n].mode = q->queue[i]->one->mode;
  43                         p->parent[n].status = q->queue[i]->status;
  44                         *tail = p;
  45                         tail = &p->next;
  46                 }
  47                 return list;
  48         }
  49
  50         for (p = curr; p; p = p->next) {
  51                 int found = 0;
  52                 if (!p->len)
  53                         continue;
  54                 for (i = 0; i < q->nr; i++) {
  55                         const char *path;
  56                         int len;
  57
  58                         if (diff_unmodified_pair(q->queue[i]))
  59                                 continue;
  60                         path = q->queue[i]->two->path;
  61                         len = strlen(path);
  62                         if (len == p->len && !memcmp(path, p->path, len)) {
  63                                 found = 1;
  64                                 hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
  65                                 p->parent[n].mode = q->queue[i]->one->mode;
  66                                 p->parent[n].status = q->queue[i]->status;
  67                                 break;
  68                         }
  69                 }
  70                 if (!found)
  71                         p->len = 0;
  72         }
  73         return curr;
  74 }
  75
  76 /* Lines lost from parent */
  77 struct lline {
  78         struct lline *next, *prev;
  79         int len;
  80         unsigned long parent_map;
  81         char line[FLEX_ARRAY];
  82 };
  83
  84 /* Lines lost from current parent (before coalescing) */
  85 struct plost {
  86         struct lline *lost_head, *lost_tail;
  87         int len;
  88 };
  89
  90 /* Lines surviving in the merge result */
  91 struct sline {
  92         /* Accumulated and coalesced lost lines */
  93         struct lline *lost;
  94         int lenlost;
  95         struct plost plost;
  96         char *bol;
  97         int len;
  98         /* bit 0 up to (N-1) are on if the parent has this line (i.e.
  99          * we did not change it).
 100          * bit N is used for "interesting" lines, including context.
 101          * bit (N+1) is used for "do not show deletion before this".
 102          */
 103         unsigned long flag;
 104         unsigned long *p_lno;
 105 };
 106
 107 static int match_string_spaces(const char *line1, int len1,
 108                                const char *line2, int len2,
 109                                long flags)
 110 {
 111         if (flags & XDF_WHITESPACE_FLAGS) {
 112                 for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
 113                 for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
 114         }
 115
 116         if (!(flags & (XDF_IGNORE_WHITESPACE | XDF_IGNORE_WHITESPACE_CHANGE)))
 117                 return (len1 == len2 && !memcmp(line1, line2, len1));
 118
 119         while (len1 > 0 && len2 > 0) {
 120                 len1--;
 121                 len2--;
 122                 if (XDL_ISSPACE(line1[len1]) || XDL_ISSPACE(line2[len2])) {
 123                         if ((flags & XDF_IGNORE_WHITESPACE_CHANGE) &&
 124                             (!XDL_ISSPACE(line1[len1]) || !XDL_ISSPACE(line2[len2])))
 125                                 return 0;
 126
 127                         for (; len1 > 0 && XDL_ISSPACE(line1[len1]); len1--);
 128                         for (; len2 > 0 && XDL_ISSPACE(line2[len2]); len2--);
 129                 }
 130                 if (line1[len1] != line2[len2])
 131                         return 0;
 132         }
 133
 134         if (flags & XDF_IGNORE_WHITESPACE) {
 135                 /* Consume remaining spaces */
 136                 for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
 137                 for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
 138         }
 139
 140         /* We matched full line1 and line2 */
 141         if (!len1 && !len2)
 142                 return 1;
 143
 144         return 0;
 145 }
 146
 147 enum coalesce_direction { MATCH, BASE, NEW };
 148
 149 /* Coalesce new lines into base by finding LCS */
 150 static struct lline *coalesce_lines(struct lline *base, int *lenbase,
 151                                     struct lline *new, int lennew,
 152                                     unsigned long parent, long flags)
 153 {
 154         int **lcs;
 155         enum coalesce_direction **directions;
 156         struct lline *baseend, *newend = NULL;
 157         int i, j, origbaselen = *lenbase;
 158
 159         if (new == NULL)
 160                 return base;
 161
 162         if (base == NULL) {
 163                 *lenbase = lennew;
 164                 return new;
 165         }
 166
 167         /*
 168          * Coalesce new lines into base by finding the LCS
 169          * - Create the table to run dynamic programming
 170          * - Compute the LCS
 171          * - Then reverse read the direction structure:
 172          *   - If we have MATCH, assign parent to base flag, and consume
 173          *   both baseend and newend
 174          *   - Else if we have BASE, consume baseend
 175          *   - Else if we have NEW, insert newend lline into base and
 176          *   consume newend
 177          */
 178         lcs = xcalloc(origbaselen + 1, sizeof(int*));
 179         directions = xcalloc(origbaselen + 1, sizeof(enum coalesce_direction*));
 180         for (i = 0; i < origbaselen + 1; i++) {
 181                 lcs[i] = xcalloc(lennew + 1, sizeof(int));
 182                 directions[i] = xcalloc(lennew + 1, sizeof(enum coalesce_direction));
 183                 directions[i][0] = BASE;
 184         }
 185         for (j = 1; j < lennew + 1; j++)
 186                 directions[0][j] = NEW;
 187
 188         for (i = 1, baseend = base; i < origbaselen + 1; i++) {
 189                 for (j = 1, newend = new; j < lennew + 1; j++) {
 190                         if (match_string_spaces(baseend->line, baseend->len,
 191                                                 newend->line, newend->len, flags)) {
 192                                 lcs[i][j] = lcs[i - 1][j - 1] + 1;
 193                                 directions[i][j] = MATCH;
 194                         } else if (lcs[i][j - 1] >= lcs[i - 1][j]) {
 195                                 lcs[i][j] = lcs[i][j - 1];
 196                                 directions[i][j] = NEW;
 197                         } else {
 198                                 lcs[i][j] = lcs[i - 1][j];
 199                                 directions[i][j] = BASE;
 200                         }
 201                         if (newend->next)
 202                                 newend = newend->next;
 203                 }
 204                 if (baseend->next)
 205                         baseend = baseend->next;
 206         }
 207
 208         for (i = 0; i < origbaselen + 1; i++)
 209                 free(lcs[i]);
 210         free(lcs);
 211
 212         /* At this point, baseend and newend point to the end of each lists */
 213         i--;
 214         j--;
 215         while (i != 0 || j != 0) {
 216                 if (directions[i][j] == MATCH) {
 217                         baseend->parent_map |= 1<<parent;
 218                         baseend = baseend->prev;
 219                         newend = newend->prev;
 220                         i--;
 221                         j--;
 222                 } else if (directions[i][j] == NEW) {
 223                         struct lline *lline;
 224
 225                         lline = newend;
 226                         /* Remove lline from new list and update newend */
 227                         if (lline->prev)
 228                                 lline->prev->next = lline->next;
 229                         else
 230                                 new = lline->next;
 231                         if (lline->next)
 232                                 lline->next->prev = lline->prev;
 233
 234                         newend = lline->prev;
 235                         j--;
 236
 237                         /* Add lline to base list */
 238                         if (baseend) {
 239                                 lline->next = baseend->next;
 240                                 lline->prev = baseend;
 241                                 if (lline->prev)
 242                                         lline->prev->next = lline;
 243                         }
 244                         else {
 245                                 lline->next = base;
 246                                 base = lline;
 247                         }
 248                         (*lenbase)++;
 249
 250                         if (lline->next)
 251                                 lline->next->prev = lline;
 252
 253                 } else {
 254                         baseend = baseend->prev;
 255                         i--;
 256                 }
 257         }
 258
 259         newend = new;
 260         while (newend) {
 261                 struct lline *lline = newend;
 262                 newend = newend->next;
 263                 free(lline);
 264         }
 265
 266         for (i = 0; i < origbaselen + 1; i++)
 267                 free(directions[i]);
 268         free(directions);
 269
 270         return base;
 271 }
 272
 273 static char *grab_blob(const unsigned char *sha1, unsigned int mode,
 274                        unsigned long *size, struct userdiff_driver *textconv,
 275                        const char *path)
 276 {
 277         char *blob;
 278         enum object_type type;
 279
 280         if (S_ISGITLINK(mode)) {
 281                 blob = xmalloc(100);
 282                 *size = snprintf(blob, 100,
 283                                  "Subproject commit %s\n", sha1_to_hex(sha1));
 284         } else if (is_null_sha1(sha1)) {
 285                 /* deleted blob */
 286                 *size = 0;
 287                 return xcalloc(1, 1);
 288         } else if (textconv) {
 289                 struct diff_filespec *df = alloc_filespec(path);
 290                 fill_filespec(df, sha1, 1, mode);
 291                 *size = fill_textconv(textconv, df, &blob);
 292                 free_filespec(df);
 293         } else {
 294                 blob = read_sha1_file(sha1, &type, size);
 295                 if (type != OBJ_BLOB)
 296                         die("object '%s' is not a blob!", sha1_to_hex(sha1));
 297         }
 298         return blob;
 299 }
 300
 301 static void append_lost(struct sline *sline, int n, const char *line, int len)
 302 {
 303         struct lline *lline;
 304         unsigned long this_mask = (1UL<<n);
 305         if (line[len-1] == '\n')
 306                 len--;
 307
 308         lline = xmalloc(sizeof(*lline) + len + 1);
 309         lline->len = len;
 310         lline->next = NULL;
 311         lline->prev = sline->plost.lost_tail;
 312         if (lline->prev)
 313                 lline->prev->next = lline;
 314         else
 315                 sline->plost.lost_head = lline;
 316         sline->plost.lost_tail = lline;
 317         sline->plost.len++;
 318         lline->parent_map = this_mask;
 319         memcpy(lline->line, line, len);
 320         lline->line[len] = 0;
 321 }
 322
 323 struct combine_diff_state {
 324         unsigned int lno;
 325         int ob, on, nb, nn;
 326         unsigned long nmask;
 327         int num_parent;
 328         int n;
 329         struct sline *sline;
 330         struct sline *lost_bucket;
 331 };
 332
 333 static void consume_line(void *state_, char *line, unsigned long len)
 334 {
 335         struct combine_diff_state *state = state_;
 336         if (5 < len && !memcmp("@@ -", line, 4)) {
 337                 if (parse_hunk_header(line, len,
 338                                       &state->ob, &state->on,
 339                                       &state->nb, &state->nn))
 340                         return;
 341                 state->lno = state->nb;
 342                 if (state->nn == 0) {
 343                         /* @@ -X,Y +N,0 @@ removed Y lines
 344                          * that would have come *after* line N
 345                          * in the result.  Our lost buckets hang
 346                          * to the line after the removed lines,
 347                          *
 348                          * Note that this is correct even when N == 0,
 349                          * in which case the hunk removes the first
 350                          * line in the file.
 351                          */
 352                         state->lost_bucket = &state->sline[state->nb];
 353                         if (!state->nb)
 354                                 state->nb = 1;
 355                 } else {
 356                         state->lost_bucket = &state->sline[state->nb-1];
 357                 }
 358                 if (!state->sline[state->nb-1].p_lno)
 359                         state->sline[state->nb-1].p_lno =
 360                                 xcalloc(state->num_parent,
 361                                         sizeof(unsigned long));
 362                 state->sline[state->nb-1].p_lno[state->n] = state->ob;
 363                 return;
 364         }
 365         if (!state->lost_bucket)
 366                 return; /* not in any hunk yet */
 367         switch (line[0]) {
 368         case '-':
 369                 append_lost(state->lost_bucket, state->n, line+1, len-1);
 370                 break;
 371         case '+':
 372                 state->sline[state->lno-1].flag |= state->nmask;
 373                 state->lno++;
 374                 break;
 375         }
 376 }
 377
 378 static void combine_diff(const unsigned char *parent, unsigned int mode,
 379                          mmfile_t *result_file,
 380                          struct sline *sline, unsigned int cnt, int n,
 381                          int num_parent, int result_deleted,
 382                          struct userdiff_driver *textconv,
 383                          const char *path, long flags)
 384 {
 385         unsigned int p_lno, lno;
 386         unsigned long nmask = (1UL << n);
 387         xpparam_t xpp;
 388         xdemitconf_t xecfg;
 389         mmfile_t parent_file;
 390         struct combine_diff_state state;
 391         unsigned long sz;
 392
 393         if (result_deleted)
 394                 return; /* result deleted */
 395
 396         parent_file.ptr = grab_blob(parent, mode, &sz, textconv, path);
 397         parent_file.size = sz;
 398         memset(&xpp, 0, sizeof(xpp));
 399         xpp.flags = flags;
 400         memset(&xecfg, 0, sizeof(xecfg));
 401         memset(&state, 0, sizeof(state));
 402         state.nmask = nmask;
 403         state.sline = sline;
 404         state.lno = 1;
 405         state.num_parent = num_parent;
 406         state.n = n;
 407
 408         xdi_diff_outf(&parent_file, result_file, consume_line, &state,
 409                       &xpp, &xecfg);
 410         free(parent_file.ptr);
 411
 412         /* Assign line numbers for this parent.
 413          *
 414          * sline[lno].p_lno[n] records the first line number
 415          * (counting from 1) for parent N if the final hunk display
 416          * started by showing sline[lno] (possibly showing the lost
 417          * lines attached to it first).
 418          */
 419         for (lno = 0,  p_lno = 1; lno <= cnt; lno++) {
 420                 struct lline *ll;
 421                 sline[lno].p_lno[n] = p_lno;
 422
 423                 /* Coalesce new lines */
 424                 if (sline[lno].plost.lost_head) {
 425                         struct sline *sl = &sline[lno];
 426                         sl->lost = coalesce_lines(sl->lost, &sl->lenlost,
 427                                                   sl->plost.lost_head,
 428                                                   sl->plost.len, n, flags);
 429                         sl->plost.lost_head = sl->plost.lost_tail = NULL;
 430                         sl->plost.len = 0;
 431                 }
 432
 433                 /* How many lines would this sline advance the p_lno? */
 434                 ll = sline[lno].lost;
 435                 while (ll) {
 436                         if (ll->parent_map & nmask)
 437                                 p_lno++; /* '-' means parent had it */
 438                         ll = ll->next;
 439                 }
 440                 if (lno < cnt && !(sline[lno].flag & nmask))
 441                         p_lno++; /* no '+' means parent had it */
 442         }
 443         sline[lno].p_lno[n] = p_lno; /* trailer */
 444 }
 445
 446 static unsigned long context = 3;
 447 static char combine_marker = '@';
 448
 449 static int interesting(struct sline *sline, unsigned long all_mask)
 450 {
 451         /* If some parents lost lines here, or if we have added to
 452          * some parent, it is interesting.
 453          */
 454         return ((sline->flag & all_mask) || sline->lost);
 455 }
 456
 457 static unsigned long adjust_hunk_tail(struct sline *sline,
 458                                       unsigned long all_mask,
 459                                       unsigned long hunk_begin,
 460                                       unsigned long i)
 461 {
 462         /* i points at the first uninteresting line.  If the last line
 463          * of the hunk was interesting only because it has some
 464          * deletion, then it is not all that interesting for the
 465          * purpose of giving trailing context lines.  This is because
 466          * we output '-' line and then unmodified sline[i-1] itself in
 467          * that case which gives us one extra context line.
 468          */
 469         if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
 470                 i--;
 471         return i;
 472 }
 473
 474 static unsigned long find_next(struct sline *sline,
 475                                unsigned long mark,
 476                                unsigned long i,
 477                                unsigned long cnt,
 478                                int look_for_uninteresting)
 479 {
 480         /* We have examined up to i-1 and are about to look at i.
 481          * Find next interesting or uninteresting line.  Here,
 482          * "interesting" does not mean interesting(), but marked by
 483          * the give_context() function below (i.e. it includes context
 484          * lines that are not interesting to interesting() function
 485          * that are surrounded by interesting() ones.
 486          */
 487         while (i <= cnt)
 488                 if (look_for_uninteresting
 489                     ? !(sline[i].flag & mark)
 490                     : (sline[i].flag & mark))
 491                         return i;
 492                 else
 493                         i++;
 494         return i;
 495 }
 496
 497 static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
 498 {
 499         unsigned long all_mask = (1UL<<num_parent) - 1;
 500         unsigned long mark = (1UL<<num_parent);
 501         unsigned long no_pre_delete = (2UL<<num_parent);
 502         unsigned long i;
 503
 504         /* Two groups of interesting lines may have a short gap of
 505          * uninteresting lines.  Connect such groups to give them a
 506          * bit of context.
 507          *
 508          * We first start from what the interesting() function says,
 509          * and mark them with "mark", and paint context lines with the
 510          * mark.  So interesting() would still say false for such context
 511          * lines but they are treated as "interesting" in the end.
 512          */
 513         i = find_next(sline, mark, 0, cnt, 0);
 514         if (cnt < i)
 515                 return 0;
 516
 517         while (i <= cnt) {
 518                 unsigned long j = (context < i) ? (i - context) : 0;
 519                 unsigned long k;
 520
 521                 /* Paint a few lines before the first interesting line. */
 522                 while (j < i) {
 523                         if (!(sline[j].flag & mark))
 524                                 sline[j].flag |= no_pre_delete;
 525                         sline[j++].flag |= mark;
 526                 }
 527
 528         again:
 529                 /* we know up to i is to be included.  where does the
 530                  * next uninteresting one start?
 531                  */
 532                 j = find_next(sline, mark, i, cnt, 1);
 533                 if (cnt < j)
 534                         break; /* the rest are all interesting */
 535
 536                 /* lookahead context lines */
 537                 k = find_next(sline, mark, j, cnt, 0);
 538                 j = adjust_hunk_tail(sline, all_mask, i, j);
 539
 540                 if (k < j + context) {
 541                         /* k is interesting and [j,k) are not, but
 542                          * paint them interesting because the gap is small.
 543                          */
 544                         while (j < k)
 545                                 sline[j++].flag |= mark;
 546                         i = k;
 547                         goto again;
 548                 }
 549
 550                 /* j is the first uninteresting line and there is
 551                  * no overlap beyond it within context lines.  Paint
 552                  * the trailing edge a bit.
 553                  */
 554                 i = k;
 555                 k = (j + context < cnt+1) ? j + context : cnt+1;
 556                 while (j < k)
 557                         sline[j++].flag |= mark;
 558         }
 559         return 1;
 560 }
 561
 562 static int make_hunks(struct sline *sline, unsigned long cnt,
 563                        int num_parent, int dense)
 564 {
 565         unsigned long all_mask = (1UL<<num_parent) - 1;
 566         unsigned long mark = (1UL<<num_parent);
 567         unsigned long i;
 568         int has_interesting = 0;
 569
 570         for (i = 0; i <= cnt; i++) {
 571                 if (interesting(&sline[i], all_mask))
 572                         sline[i].flag |= mark;
 573                 else
 574                         sline[i].flag &= ~mark;
 575         }
 576         if (!dense)
 577                 return give_context(sline, cnt, num_parent);
 578
 579         /* Look at each hunk, and if we have changes from only one
 580          * parent, or the changes are the same from all but one
 581          * parent, mark that uninteresting.
 582          */
 583         i = 0;
 584         while (i <= cnt) {
 585                 unsigned long j, hunk_begin, hunk_end;
 586                 unsigned long same_diff;
 587                 while (i <= cnt && !(sline[i].flag & mark))
 588                         i++;
 589                 if (cnt < i)
 590                         break; /* No more interesting hunks */
 591                 hunk_begin = i;
 592                 for (j = i + 1; j <= cnt; j++) {
 593                         if (!(sline[j].flag & mark)) {
 594                                 /* Look beyond the end to see if there
 595                                  * is an interesting line after this
 596                                  * hunk within context span.
 597                                  */
 598                                 unsigned long la; /* lookahead */
 599                                 int contin = 0;
 600                                 la = adjust_hunk_tail(sline, all_mask,
 601                                                      hunk_begin, j);
 602                                 la = (la + context < cnt + 1) ?
 603                                         (la + context) : cnt + 1;
 604                                 while (la && j <= --la) {
 605                                         if (sline[la].flag & mark) {
 606                                                 contin = 1;
 607                                                 break;
 608                                         }
 609                                 }
 610                                 if (!contin)
 611                                         break;
 612                                 j = la;
 613                         }
 614                 }
 615                 hunk_end = j;
 616
 617                 /* [i..hunk_end) are interesting.  Now is it really
 618                  * interesting?  We check if there are only two versions
 619                  * and the result matches one of them.  That is, we look
 620                  * at:
 621                  *   (+) line, which records lines added to which parents;
 622                  *       this line appears in the result.
 623                  *   (-) line, which records from what parents the line
 624                  *       was removed; this line does not appear in the result.
 625                  * then check the set of parents the result has difference
 626                  * from, from all lines.  If there are lines that has
 627                  * different set of parents that the result has differences
 628                  * from, that means we have more than two versions.
 629                  *
 630                  * Even when we have only two versions, if the result does
 631                  * not match any of the parents, the it should be considered
 632                  * interesting.  In such a case, we would have all '+' line.
 633                  * After passing the above "two versions" test, that would
 634                  * appear as "the same set of parents" to be "all parents".
 635                  */
 636                 same_diff = 0;
 637                 has_interesting = 0;
 638                 for (j = i; j < hunk_end && !has_interesting; j++) {
 639                         unsigned long this_diff = sline[j].flag & all_mask;
 640                         struct lline *ll = sline[j].lost;
 641                         if (this_diff) {
 642                                 /* This has some changes.  Is it the
 643                                  * same as others?
 644                                  */
 645                                 if (!same_diff)
 646                                         same_diff = this_diff;
 647                                 else if (same_diff != this_diff) {
 648                                         has_interesting = 1;
 649                                         break;
 650                                 }
 651                         }
 652                         while (ll && !has_interesting) {
 653                                 /* Lost this line from these parents;
 654                                  * who are they?  Are they the same?
 655                                  */
 656                                 this_diff = ll->parent_map;
 657                                 if (!same_diff)
 658                                         same_diff = this_diff;
 659                                 else if (same_diff != this_diff) {
 660                                         has_interesting = 1;
 661                                 }
 662                                 ll = ll->next;
 663                         }
 664                 }
 665
 666                 if (!has_interesting && same_diff != all_mask) {
 667                         /* This hunk is not that interesting after all */
 668                         for (j = hunk_begin; j < hunk_end; j++)
 669                                 sline[j].flag &= ~mark;
 670                 }
 671                 i = hunk_end;
 672         }
 673
 674         has_interesting = give_context(sline, cnt, num_parent);
 675         return has_interesting;
 676 }
 677
 678 static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, int n, unsigned long null_context)
 679 {
 680         l0 = sline[l0].p_lno[n];
 681         l1 = sline[l1].p_lno[n];
 682         printf(" -%lu,%lu", l0, l1-l0-null_context);
 683 }
 684
 685 static int hunk_comment_line(const char *bol)
 686 {
 687         int ch;
 688
 689         if (!bol)
 690                 return 0;
 691         ch = *bol & 0xff;
 692         return (isalpha(ch) || ch == '_' || ch == '$');
 693 }
 694
 695 static void show_line_to_eol(const char *line, int len, const char *reset)
 696 {
 697         int saw_cr_at_eol = 0;
 698         if (len < 0)
 699                 len = strlen(line);
 700         saw_cr_at_eol = (len && line[len-1] == '\r');
 701
 702         printf("%.*s%s%s\n", len - saw_cr_at_eol, line,
 703                reset,
 704                saw_cr_at_eol ? "\r" : "");
 705 }
 706
 707 static void dump_sline(struct sline *sline, const char *line_prefix,
 708                        unsigned long cnt, int num_parent,
 709                        int use_color, int result_deleted)
 710 {
 711         unsigned long mark = (1UL<<num_parent);
 712         unsigned long no_pre_delete = (2UL<<num_parent);
 713         int i;
 714         unsigned long lno = 0;
 715         const char *c_frag = diff_get_color(use_color, DIFF_FRAGINFO);
 716         const char *c_func = diff_get_color(use_color, DIFF_FUNCINFO);
 717         const char *c_new = diff_get_color(use_color, DIFF_FILE_NEW);
 718         const char *c_old = diff_get_color(use_color, DIFF_FILE_OLD);
 719         const char *c_plain = diff_get_color(use_color, DIFF_PLAIN);
 720         const char *c_reset = diff_get_color(use_color, DIFF_RESET);
 721
 722         if (result_deleted)
 723                 return; /* result deleted */
 724
 725         while (1) {
 726                 unsigned long hunk_end;
 727                 unsigned long rlines;
 728                 const char *hunk_comment = NULL;
 729                 unsigned long null_context = 0;
 730
 731                 while (lno <= cnt && !(sline[lno].flag & mark)) {
 732                         if (hunk_comment_line(sline[lno].bol))
 733                                 hunk_comment = sline[lno].bol;
 734                         lno++;
 735                 }
 736                 if (cnt < lno)
 737                         break;
 738                 else {
 739                         for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
 740                                 if (!(sline[hunk_end].flag & mark))
 741                                         break;
 742                 }
 743                 rlines = hunk_end - lno;
 744                 if (cnt < hunk_end)
 745                         rlines--; /* pointing at the last delete hunk */
 746
 747                 if (!context) {
 748                         /*
 749                          * Even when running with --unified=0, all
 750                          * lines in the hunk needs to be processed in
 751                          * the loop below in order to show the
 752                          * deletion recorded in lost_head.  However,
 753                          * we do not want to show the resulting line
 754                          * with all blank context markers in such a
 755                          * case.  Compensate.
 756                          */
 757                         unsigned long j;
 758                         for (j = lno; j < hunk_end; j++)
 759                                 if (!(sline[j].flag & (mark-1)))
 760                                         null_context++;
 761                         rlines -= null_context;
 762                 }
 763
 764                 printf("%s%s", line_prefix, c_frag);
 765                 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 766                 for (i = 0; i < num_parent; i++)
 767                         show_parent_lno(sline, lno, hunk_end, i, null_context);
 768                 printf(" +%lu,%lu ", lno+1, rlines);
 769                 for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 770
 771                 if (hunk_comment) {
 772                         int comment_end = 0;
 773                         for (i = 0; i < 40; i++) {
 774                                 int ch = hunk_comment[i] & 0xff;
 775                                 if (!ch || ch == '\n')
 776                                         break;
 777                                 if (!isspace(ch))
 778                                     comment_end = i;
 779                         }
 780                         if (comment_end)
 781                                 printf("%s%s %s%s", c_reset,
 782                                                     c_plain, c_reset,
 783                                                     c_func);
 784                         for (i = 0; i < comment_end; i++)
 785                                 putchar(hunk_comment[i]);
 786                 }
 787
 788                 printf("%s\n", c_reset);
 789                 while (lno < hunk_end) {
 790                         struct lline *ll;
 791                         int j;
 792                         unsigned long p_mask;
 793                         struct sline *sl = &sline[lno++];
 794                         ll = (sl->flag & no_pre_delete) ? NULL : sl->lost;
 795                         while (ll) {
 796                                 printf("%s%s", line_prefix, c_old);
 797                                 for (j = 0; j < num_parent; j++) {
 798                                         if (ll->parent_map & (1UL<<j))
 799                                                 putchar('-');
 800                                         else
 801                                                 putchar(' ');
 802                                 }
 803                                 show_line_to_eol(ll->line, -1, c_reset);
 804                                 ll = ll->next;
 805                         }
 806                         if (cnt < lno)
 807                                 break;
 808                         p_mask = 1;
 809                         fputs(line_prefix, stdout);
 810                         if (!(sl->flag & (mark-1))) {
 811                                 /*
 812                                  * This sline was here to hang the
 813                                  * lost lines in front of it.
 814                                  */
 815                                 if (!context)
 816                                         continue;
 817                                 fputs(c_plain, stdout);
 818                         }
 819                         else
 820                                 fputs(c_new, stdout);
 821                         for (j = 0; j < num_parent; j++) {
 822                                 if (p_mask & sl->flag)
 823                                         putchar('+');
 824                                 else
 825                                         putchar(' ');
 826                                 p_mask <<= 1;
 827                         }
 828                         show_line_to_eol(sl->bol, sl->len, c_reset);
 829                 }
 830         }
 831 }
 832
 833 static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
 834                                int i, int j)
 835 {
 836         /* We have already examined parent j and we know parent i
 837          * and parent j are the same, so reuse the combined result
 838          * of parent j for parent i.
 839          */
 840         unsigned long lno, imask, jmask;
 841         imask = (1UL<<i);
 842         jmask = (1UL<<j);
 843
 844         for (lno = 0; lno <= cnt; lno++) {
 845                 struct lline *ll = sline->lost;
 846                 sline->p_lno[i] = sline->p_lno[j];
 847                 while (ll) {
 848                         if (ll->parent_map & jmask)
 849                                 ll->parent_map |= imask;
 850                         ll = ll->next;
 851                 }
 852                 if (sline->flag & jmask)
 853                         sline->flag |= imask;
 854                 sline++;
 855         }
 856         /* the overall size of the file (sline[cnt]) */
 857         sline->p_lno[i] = sline->p_lno[j];
 858 }
 859
 860 static void dump_quoted_path(const char *head,
 861                              const char *prefix,
 862                              const char *path,
 863                              const char *line_prefix,
 864                              const char *c_meta, const char *c_reset)
 865 {
 866         static struct strbuf buf = STRBUF_INIT;
 867
 868         strbuf_reset(&buf);
 869         strbuf_addstr(&buf, line_prefix);
 870         strbuf_addstr(&buf, c_meta);
 871         strbuf_addstr(&buf, head);
 872         quote_two_c_style(&buf, prefix, path, 0);
 873         strbuf_addstr(&buf, c_reset);
 874         puts(buf.buf);
 875 }
 876
 877 static void show_combined_header(struct combine_diff_path *elem,
 878                                  int num_parent,
 879                                  int dense,
 880                                  struct rev_info *rev,
 881                                  const char *line_prefix,
 882                                  int mode_differs,
 883                                  int show_file_header)
 884 {
 885         struct diff_options *opt = &rev->diffopt;
 886         int abbrev = DIFF_OPT_TST(opt, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
 887         const char *a_prefix = opt->a_prefix ? opt->a_prefix : "a/";
 888         const char *b_prefix = opt->b_prefix ? opt->b_prefix : "b/";
 889         const char *c_meta = diff_get_color_opt(opt, DIFF_METAINFO);
 890         const char *c_reset = diff_get_color_opt(opt, DIFF_RESET);
 891         const char *abb;
 892         int added = 0;
 893         int deleted = 0;
 894         int i;
 895
 896         if (rev->loginfo && !rev->no_commit_id)
 897                 show_log(rev);
 898
 899         dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
 900                          "", elem->path, line_prefix, c_meta, c_reset);
 901         printf("%s%sindex ", line_prefix, c_meta);
 902         for (i = 0; i < num_parent; i++) {
 903                 abb = find_unique_abbrev(elem->parent[i].sha1,
 904                                          abbrev);
 905                 printf("%s%s", i ? "," : "", abb);
 906         }
 907         abb = find_unique_abbrev(elem->sha1, abbrev);
 908         printf("..%s%s\n", abb, c_reset);
 909
 910         if (mode_differs) {
 911                 deleted = !elem->mode;
 912
 913                 /* We say it was added if nobody had it */
 914                 added = !deleted;
 915                 for (i = 0; added && i < num_parent; i++)
 916                         if (elem->parent[i].status !=
 917                             DIFF_STATUS_ADDED)
 918                                 added = 0;
 919                 if (added)
 920                         printf("%s%snew file mode %06o",
 921                                line_prefix, c_meta, elem->mode);
 922                 else {
 923                         if (deleted)
 924                                 printf("%s%sdeleted file ",
 925                                        line_prefix, c_meta);
 926                         printf("mode ");
 927                         for (i = 0; i < num_parent; i++) {
 928                                 printf("%s%06o", i ? "," : "",
 929                                        elem->parent[i].mode);
 930                         }
 931                         if (elem->mode)
 932                                 printf("..%06o", elem->mode);
 933                 }
 934                 printf("%s\n", c_reset);
 935         }
 936
 937         if (!show_file_header)
 938                 return;
 939
 940         if (added)
 941                 dump_quoted_path("--- ", "", "/dev/null",
 942                                  line_prefix, c_meta, c_reset);
 943         else
 944                 dump_quoted_path("--- ", a_prefix, elem->path,
 945                                  line_prefix, c_meta, c_reset);
 946         if (deleted)
 947                 dump_quoted_path("+++ ", "", "/dev/null",
 948                                  line_prefix, c_meta, c_reset);
 949         else
 950                 dump_quoted_path("+++ ", b_prefix, elem->path,
 951                                  line_prefix, c_meta, c_reset);
 952 }
 953
 954 static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
 955                             int dense, int working_tree_file,
 956                             struct rev_info *rev)
 957 {
 958         struct diff_options *opt = &rev->diffopt;
 959         unsigned long result_size, cnt, lno;
 960         int result_deleted = 0;
 961         char *result, *cp;
 962         struct sline *sline; /* survived lines */
 963         int mode_differs = 0;
 964         int i, show_hunks;
 965         mmfile_t result_file;
 966         struct userdiff_driver *userdiff;
 967         struct userdiff_driver *textconv = NULL;
 968         int is_binary;
 969         const char *line_prefix = diff_line_prefix(opt);
 970
 971         context = opt->context;
 972         userdiff = userdiff_find_by_path(elem->path);
 973         if (!userdiff)
 974                 userdiff = userdiff_find_by_name("default");
 975         if (DIFF_OPT_TST(opt, ALLOW_TEXTCONV))
 976                 textconv = userdiff_get_textconv(userdiff);
 977
 978         /* Read the result of merge first */
 979         if (!working_tree_file)
 980                 result = grab_blob(elem->sha1, elem->mode, &result_size,
 981                                    textconv, elem->path);
 982         else {
 983                 /* Used by diff-tree to read from the working tree */
 984                 struct stat st;
 985                 int fd = -1;
 986
 987                 if (lstat(elem->path, &st) < 0)
 988                         goto deleted_file;
 989
 990                 if (S_ISLNK(st.st_mode)) {
 991                         struct strbuf buf = STRBUF_INIT;
 992
 993                         if (strbuf_readlink(&buf, elem->path, st.st_size) < 0) {
 994                                 error("readlink(%s): %s", elem->path,
 995                                       strerror(errno));
 996                                 return;
 997                         }
 998                         result_size = buf.len;
 999                         result = strbuf_detach(&buf, NULL);
1000                         elem->mode = canon_mode(st.st_mode);
1001                 } else if (S_ISDIR(st.st_mode)) {
1002                         unsigned char sha1[20];
1003                         if (resolve_gitlink_ref(elem->path, "HEAD", sha1) < 0)
1004                                 result = grab_blob(elem->sha1, elem->mode,
1005                                                    &result_size, NULL, NULL);
1006                         else
1007                                 result = grab_blob(sha1, elem->mode,
1008                                                    &result_size, NULL, NULL);
1009                 } else if (textconv) {
1010                         struct diff_filespec *df = alloc_filespec(elem->path);
1011                         fill_filespec(df, null_sha1, 0, st.st_mode);
1012                         result_size = fill_textconv(textconv, df, &result);
1013                         free_filespec(df);
1014                 } else if (0 <= (fd = open(elem->path, O_RDONLY))) {
1015                         size_t len = xsize_t(st.st_size);
1016                         ssize_t done;
1017                         int is_file, i;
1018
1019                         elem->mode = canon_mode(st.st_mode);
1020                         /* if symlinks don't work, assume symlink if all parents
1021                          * are symlinks
1022                          */
1023                         is_file = has_symlinks;
1024                         for (i = 0; !is_file && i < num_parent; i++)
1025                                 is_file = !S_ISLNK(elem->parent[i].mode);
1026                         if (!is_file)
1027                                 elem->mode = canon_mode(S_IFLNK);
1028
1029                         result_size = len;
1030                         result = xmalloc(len + 1);
1031
1032                         done = read_in_full(fd, result, len);
1033                         if (done < 0)
1034                                 die_errno("read error '%s'", elem->path);
1035                         else if (done < len)
1036                                 die("early EOF '%s'", elem->path);
1037
1038                         result[len] = 0;
1039
1040                         /* If not a fake symlink, apply filters, e.g. autocrlf */
1041                         if (is_file) {
1042                                 struct strbuf buf = STRBUF_INIT;
1043
1044                                 if (convert_to_git(elem->path, result, len, &buf, safe_crlf)) {
1045                                         free(result);
1046                                         result = strbuf_detach(&buf, &len);
1047                                         result_size = len;
1048                                 }
1049                         }
1050                 }
1051                 else {
1052                 deleted_file:
1053                         result_deleted = 1;
1054                         result_size = 0;
1055                         elem->mode = 0;
1056                         result = xcalloc(1, 1);
1057                 }
1058
1059                 if (0 <= fd)
1060                         close(fd);
1061         }
1062
1063         for (i = 0; i < num_parent; i++) {
1064                 if (elem->parent[i].mode != elem->mode) {
1065                         mode_differs = 1;
1066                         break;
1067                 }
1068         }
1069
1070         if (textconv)
1071                 is_binary = 0;
1072         else if (userdiff->binary != -1)
1073                 is_binary = userdiff->binary;
1074         else {
1075                 is_binary = buffer_is_binary(result, result_size);
1076                 for (i = 0; !is_binary && i < num_parent; i++) {
1077                         char *buf;
1078                         unsigned long size;
1079                         buf = grab_blob(elem->parent[i].sha1,
1080                                         elem->parent[i].mode,
1081                                         &size, NULL, NULL);
1082                         if (buffer_is_binary(buf, size))
1083                                 is_binary = 1;
1084                         free(buf);
1085                 }
1086         }
1087         if (is_binary) {
1088                 show_combined_header(elem, num_parent, dense, rev,
1089                                      line_prefix, mode_differs, 0);
1090                 printf("Binary files differ\n");
1091                 free(result);
1092                 return;
1093         }
1094
1095         for (cnt = 0, cp = result; cp < result + result_size; cp++) {
1096                 if (*cp == '\n')
1097                         cnt++;
1098         }
1099         if (result_size && result[result_size-1] != '\n')
1100                 cnt++; /* incomplete line */
1101
1102         sline = xcalloc(cnt+2, sizeof(*sline));
1103         sline[0].bol = result;
1104         for (lno = 0, cp = result; cp < result + result_size; cp++) {
1105                 if (*cp == '\n') {
1106                         sline[lno].len = cp - sline[lno].bol;
1107                         lno++;
1108                         if (lno < cnt)
1109                                 sline[lno].bol = cp + 1;
1110                 }
1111         }
1112         if (result_size && result[result_size-1] != '\n')
1113                 sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
1114
1115         result_file.ptr = result;
1116         result_file.size = result_size;
1117
1118         /* Even p_lno[cnt+1] is valid -- that is for the end line number
1119          * for deletion hunk at the end.
1120          */
1121         sline[0].p_lno = xcalloc((cnt+2) * num_parent, sizeof(unsigned long));
1122         for (lno = 0; lno <= cnt; lno++)
1123                 sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
1124
1125         for (i = 0; i < num_parent; i++) {
1126                 int j;
1127                 for (j = 0; j < i; j++) {
1128                         if (!hashcmp(elem->parent[i].sha1,
1129                                      elem->parent[j].sha1)) {
1130                                 reuse_combine_diff(sline, cnt, i, j);
1131                                 break;
1132                         }
1133                 }
1134                 if (i <= j)
1135                         combine_diff(elem->parent[i].sha1,
1136                                      elem->parent[i].mode,
1137                                      &result_file, sline,
1138                                      cnt, i, num_parent, result_deleted,
1139                                      textconv, elem->path, opt->xdl_opts);
1140         }
1141
1142         show_hunks = make_hunks(sline, cnt, num_parent, dense);
1143
1144         if (show_hunks || mode_differs || working_tree_file) {
1145                 show_combined_header(elem, num_parent, dense, rev,
1146                                      line_prefix, mode_differs, 1);
1147                 dump_sline(sline, line_prefix, cnt, num_parent,
1148                            opt->use_color, result_deleted);
1149         }
1150         free(result);
1151
1152         for (lno = 0; lno < cnt; lno++) {
1153                 if (sline[lno].lost) {
1154                         struct lline *ll = sline[lno].lost;
1155                         while (ll) {
1156                                 struct lline *tmp = ll;
1157                                 ll = ll->next;
1158                                 free(tmp);
1159                         }
1160                 }
1161         }
1162         free(sline[0].p_lno);
1163         free(sline);
1164 }
1165
1166 static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct rev_info *rev)
1167 {
1168         struct diff_options *opt = &rev->diffopt;
1169         int line_termination, inter_name_termination, i;
1170         const char *line_prefix = diff_line_prefix(opt);
1171
1172         line_termination = opt->line_termination;
1173         inter_name_termination = '\t';
1174         if (!line_termination)
1175                 inter_name_termination = 0;
1176
1177         if (rev->loginfo && !rev->no_commit_id)
1178                 show_log(rev);
1179
1180
1181         if (opt->output_format & DIFF_FORMAT_RAW) {
1182                 printf("%s", line_prefix);
1183
1184                 /* As many colons as there are parents */
1185                 for (i = 0; i < num_parent; i++)
1186                         putchar(':');
1187
1188                 /* Show the modes */
1189                 for (i = 0; i < num_parent; i++)
1190                         printf("%06o ", p->parent[i].mode);
1191                 printf("%06o", p->mode);
1192
1193                 /* Show sha1's */
1194                 for (i = 0; i < num_parent; i++)
1195                         printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
1196                                                          opt->abbrev));
1197                 printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
1198         }
1199
1200         if (opt->output_format & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS)) {
1201                 for (i = 0; i < num_parent; i++)
1202                         putchar(p->parent[i].status);
1203                 putchar(inter_name_termination);
1204         }
1205
1206         write_name_quoted(p->path, stdout, line_termination);
1207 }
1208
1209 /*
1210  * The result (p->elem) is from the working tree and their
1211  * parents are typically from multiple stages during a merge
1212  * (i.e. diff-files) or the state in HEAD and in the index
1213  * (i.e. diff-index).
1214  */
1215 void show_combined_diff(struct combine_diff_path *p,
1216                        int num_parent,
1217                        int dense,
1218                        struct rev_info *rev)
1219 {
1220         struct diff_options *opt = &rev->diffopt;
1221
1222         if (!p->len)
1223                 return;
1224         if (opt->output_format & (DIFF_FORMAT_RAW |
1225                                   DIFF_FORMAT_NAME |
1226                                   DIFF_FORMAT_NAME_STATUS))
1227                 show_raw_diff(p, num_parent, rev);
1228         else if (opt->output_format & DIFF_FORMAT_PATCH)
1229                 show_patch_diff(p, num_parent, dense, 1, rev);
1230 }
1231
1232 static void free_combined_pair(struct diff_filepair *pair)
1233 {
1234         free(pair->two);
1235         free(pair);
1236 }
1237
1238 /*
1239  * A combine_diff_path expresses N parents on the LHS against 1 merge
1240  * result. Synthesize a diff_filepair that has N entries on the "one"
1241  * side and 1 entry on the "two" side.
1242  *
1243  * In the future, we might want to add more data to combine_diff_path
1244  * so that we can fill fields we are ignoring (most notably, size) here,
1245  * but currently nobody uses it, so this should suffice for now.
1246  */
1247 static struct diff_filepair *combined_pair(struct combine_diff_path *p,
1248                                            int num_parent)
1249 {
1250         int i;
1251         struct diff_filepair *pair;
1252         struct diff_filespec *pool;
1253
1254         pair = xmalloc(sizeof(*pair));
1255         pool = xcalloc(num_parent + 1, sizeof(struct diff_filespec));
1256         pair->one = pool + 1;
1257         pair->two = pool;
1258
1259         for (i = 0; i < num_parent; i++) {
1260                 pair->one[i].path = p->path;
1261                 pair->one[i].mode = p->parent[i].mode;
1262                 hashcpy(pair->one[i].sha1, p->parent[i].sha1);
1263                 pair->one[i].sha1_valid = !is_null_sha1(p->parent[i].sha1);
1264                 pair->one[i].has_more_entries = 1;
1265         }
1266         pair->one[num_parent - 1].has_more_entries = 0;
1267
1268         pair->two->path = p->path;
1269         pair->two->mode = p->mode;
1270         hashcpy(pair->two->sha1, p->sha1);
1271         pair->two->sha1_valid = !is_null_sha1(p->sha1);
1272         return pair;
1273 }
1274
1275 static void handle_combined_callback(struct diff_options *opt,
1276                                      struct combine_diff_path *paths,
1277                                      int num_parent,
1278                                      int num_paths)
1279 {
1280         struct combine_diff_path *p;
1281         struct diff_queue_struct q;
1282         int i;
1283
1284         q.queue = xcalloc(num_paths, sizeof(struct diff_filepair *));
1285         q.alloc = num_paths;
1286         q.nr = num_paths;
1287         for (i = 0, p = paths; p; p = p->next) {
1288                 if (!p->len)
1289                         continue;
1290                 q.queue[i++] = combined_pair(p, num_parent);
1291         }
1292         opt->format_callback(&q, opt, opt->format_callback_data);
1293         for (i = 0; i < num_paths; i++)
1294                 free_combined_pair(q.queue[i]);
1295         free(q.queue);
1296 }
1297
1298 void diff_tree_combined(const unsigned char *sha1,
1299                         const struct sha1_array *parents,
1300                         int dense,
1301                         struct rev_info *rev)
1302 {
1303         struct diff_options *opt = &rev->diffopt;
1304         struct diff_options diffopts;
1305         struct combine_diff_path *p, *paths = NULL;
1306         int i, num_paths, needsep, show_log_first, num_parent = parents->nr;
1307
1308         diffopts = *opt;
1309         copy_pathspec(&diffopts.pathspec, &opt->pathspec);
1310         diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
1311         DIFF_OPT_SET(&diffopts, RECURSIVE);
1312         DIFF_OPT_CLR(&diffopts, ALLOW_EXTERNAL);
1313
1314         show_log_first = !!rev->loginfo && !rev->no_commit_id;
1315         needsep = 0;
1316         /* find set of paths that everybody touches */
1317         for (i = 0; i < num_parent; i++) {
1318                 /* show stat against the first parent even
1319                  * when doing combined diff.
1320                  */
1321                 int stat_opt = (opt->output_format &
1322                                 (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
1323                 if (i == 0 && stat_opt)
1324                         diffopts.output_format = stat_opt;
1325                 else
1326                         diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
1327                 diff_tree_sha1(parents->sha1[i], sha1, "", &diffopts);
1328                 diffcore_std(&diffopts);
1329                 paths = intersect_paths(paths, i, num_parent);
1330
1331                 if (show_log_first && i == 0) {
1332                         show_log(rev);
1333
1334                         if (rev->verbose_header && opt->output_format)
1335                                 printf("%s%c", diff_line_prefix(opt),
1336                                        opt->line_termination);
1337                 }
1338                 diff_flush(&diffopts);
1339         }
1340
1341         /* find out surviving paths */
1342         for (num_paths = 0, p = paths; p; p = p->next) {
1343                 if (p->len)
1344                         num_paths++;
1345         }
1346         if (num_paths) {
1347                 if (opt->output_format & (DIFF_FORMAT_RAW |
1348                                           DIFF_FORMAT_NAME |
1349                                           DIFF_FORMAT_NAME_STATUS)) {
1350                         for (p = paths; p; p = p->next) {
1351                                 if (p->len)
1352                                         show_raw_diff(p, num_parent, rev);
1353                         }
1354                         needsep = 1;
1355                 }
1356                 else if (opt->output_format &
1357                          (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT))
1358                         needsep = 1;
1359                 else if (opt->output_format & DIFF_FORMAT_CALLBACK)
1360                         handle_combined_callback(opt, paths, num_parent, num_paths);
1361
1362                 if (opt->output_format & DIFF_FORMAT_PATCH) {
1363                         if (needsep)
1364                                 printf("%s%c", diff_line_prefix(opt),
1365                                        opt->line_termination);
1366                         for (p = paths; p; p = p->next) {
1367                                 if (p->len)
1368                                         show_patch_diff(p, num_parent, dense,
1369                                                         0, rev);
1370                         }
1371                 }
1372         }
1373
1374         /* Clean things up */
1375         while (paths) {
1376                 struct combine_diff_path *tmp = paths;
1377                 paths = paths->next;
1378                 free(tmp);
1379         }
1380
1381         free_pathspec(&diffopts.pathspec);
1382 }
1383
1384 void diff_tree_combined_merge(const struct commit *commit, int dense,
1385                               struct rev_info *rev)
1386 {
1387         struct commit_list *parent = get_saved_parents(rev, commit);
1388         struct sha1_array parents = SHA1_ARRAY_INIT;
1389
1390         while (parent) {
1391                 sha1_array_append(&parents, parent->item->object.sha1);
1392                 parent = parent->next;
1393         }
1394         diff_tree_combined(commit->object.sha1, &parents, dense, rev);
1395         sha1_array_clear(&parents);
1396 }