combine-diff.con commit Fix pack-index issue on 64-bit platforms a bit more portably. (1b9bc5a)
   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
   9static int uninteresting(struct diff_filepair *p)
  10{
  11        if (diff_unmodified_pair(p))
  12                return 1;
  13        return 0;
  14}
  15
  16static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
  17{
  18        struct diff_queue_struct *q = &diff_queued_diff;
  19        struct combine_diff_path *p;
  20        int i;
  21
  22        if (!n) {
  23                struct combine_diff_path *list = NULL, **tail = &list;
  24                for (i = 0; i < q->nr; i++) {
  25                        int len;
  26                        const char *path;
  27                        if (uninteresting(q->queue[i]))
  28                                continue;
  29                        path = q->queue[i]->two->path;
  30                        len = strlen(path);
  31                        p = xmalloc(combine_diff_path_size(num_parent, len));
  32                        p->path = (char*) &(p->parent[num_parent]);
  33                        memcpy(p->path, path, len);
  34                        p->path[len] = 0;
  35                        p->len = len;
  36                        p->next = NULL;
  37                        memset(p->parent, 0,
  38                               sizeof(p->parent[0]) * num_parent);
  39
  40                        memcpy(p->sha1, q->queue[i]->two->sha1, 20);
  41                        p->mode = q->queue[i]->two->mode;
  42                        memcpy(p->parent[n].sha1, q->queue[i]->one->sha1, 20);
  43                        p->parent[n].mode = q->queue[i]->one->mode;
  44                        p->parent[n].status = q->queue[i]->status;
  45                        *tail = p;
  46                        tail = &p->next;
  47                }
  48                return list;
  49        }
  50
  51        for (p = curr; p; p = p->next) {
  52                int found = 0;
  53                if (!p->len)
  54                        continue;
  55                for (i = 0; i < q->nr; i++) {
  56                        const char *path;
  57                        int len;
  58
  59                        if (uninteresting(q->queue[i]))
  60                                continue;
  61                        path = q->queue[i]->two->path;
  62                        len = strlen(path);
  63                        if (len == p->len && !memcmp(path, p->path, len)) {
  64                                found = 1;
  65                                memcpy(p->parent[n].sha1,
  66                                       q->queue[i]->one->sha1, 20);
  67                                p->parent[n].mode = q->queue[i]->one->mode;
  68                                p->parent[n].status = q->queue[i]->status;
  69                                break;
  70                        }
  71                }
  72                if (!found)
  73                        p->len = 0;
  74        }
  75        return curr;
  76}
  77
  78/* Lines lost from parent */
  79struct lline {
  80        struct lline *next;
  81        int len;
  82        unsigned long parent_map;
  83        char line[FLEX_ARRAY];
  84};
  85
  86/* Lines surviving in the merge result */
  87struct sline {
  88        struct lline *lost_head, **lost_tail;
  89        char *bol;
  90        int len;
  91        /* bit 0 up to (N-1) are on if the parent has this line (i.e.
  92         * we did not change it).
  93         * bit N is used for "interesting" lines, including context.
  94         */
  95        unsigned long flag;
  96        unsigned long *p_lno;
  97};
  98
  99static char *grab_blob(const unsigned char *sha1, unsigned long *size)
 100{
 101        char *blob;
 102        char type[20];
 103        if (!memcmp(sha1, null_sha1, 20)) {
 104                /* deleted blob */
 105                *size = 0;
 106                return xcalloc(1, 1);
 107        }
 108        blob = read_sha1_file(sha1, type, size);
 109        if (strcmp(type, blob_type))
 110                die("object '%s' is not a blob!", sha1_to_hex(sha1));
 111        return blob;
 112}
 113
 114static void append_lost(struct sline *sline, int n, const char *line, int len)
 115{
 116        struct lline *lline;
 117        unsigned long this_mask = (1UL<<n);
 118        if (line[len-1] == '\n')
 119                len--;
 120
 121        /* Check to see if we can squash things */
 122        if (sline->lost_head) {
 123                struct lline *last_one = NULL;
 124                /* We cannot squash it with earlier one */
 125                for (lline = sline->lost_head;
 126                     lline;
 127                     lline = lline->next)
 128                        if (lline->parent_map & this_mask)
 129                                last_one = lline;
 130                lline = last_one ? last_one->next : sline->lost_head;
 131                while (lline) {
 132                        if (lline->len == len &&
 133                            !memcmp(lline->line, line, len)) {
 134                                lline->parent_map |= this_mask;
 135                                return;
 136                        }
 137                        lline = lline->next;
 138                }
 139        }
 140
 141        lline = xmalloc(sizeof(*lline) + len + 1);
 142        lline->len = len;
 143        lline->next = NULL;
 144        lline->parent_map = this_mask;
 145        memcpy(lline->line, line, len);
 146        lline->line[len] = 0;
 147        *sline->lost_tail = lline;
 148        sline->lost_tail = &lline->next;
 149}
 150
 151struct combine_diff_state {
 152        struct xdiff_emit_state xm;
 153
 154        unsigned int lno;
 155        int ob, on, nb, nn;
 156        unsigned long nmask;
 157        int num_parent;
 158        int n;
 159        struct sline *sline;
 160        struct sline *lost_bucket;
 161};
 162
 163static void consume_line(void *state_, char *line, unsigned long len)
 164{
 165        struct combine_diff_state *state = state_;
 166        if (5 < len && !memcmp("@@ -", line, 4)) {
 167                if (parse_hunk_header(line, len,
 168                                      &state->ob, &state->on,
 169                                      &state->nb, &state->nn))
 170                        return;
 171                state->lno = state->nb;
 172                if (!state->nb)
 173                        /* @@ -1,2 +0,0 @@ to remove the
 174                         * first two lines...
 175                         */
 176                        state->nb = 1;
 177                if (state->nn == 0)
 178                        /* @@ -X,Y +N,0 @@ removed Y lines
 179                         * that would have come *after* line N
 180                         * in the result.  Our lost buckets hang
 181                         * to the line after the removed lines,
 182                         */
 183                        state->lost_bucket = &state->sline[state->nb];
 184                else
 185                        state->lost_bucket = &state->sline[state->nb-1];
 186                if (!state->sline[state->nb-1].p_lno)
 187                        state->sline[state->nb-1].p_lno =
 188                                xcalloc(state->num_parent,
 189                                        sizeof(unsigned long));
 190                state->sline[state->nb-1].p_lno[state->n] = state->ob;
 191                return;
 192        }
 193        if (!state->lost_bucket)
 194                return; /* not in any hunk yet */
 195        switch (line[0]) {
 196        case '-':
 197                append_lost(state->lost_bucket, state->n, line+1, len-1);
 198                break;
 199        case '+':
 200                state->sline[state->lno-1].flag |= state->nmask;
 201                state->lno++;
 202                break;
 203        }
 204}
 205
 206static void combine_diff(const unsigned char *parent, mmfile_t *result_file,
 207                         struct sline *sline, int cnt, int n, int num_parent)
 208{
 209        unsigned int p_lno, lno;
 210        unsigned long nmask = (1UL << n);
 211        xpparam_t xpp;
 212        xdemitconf_t xecfg;
 213        mmfile_t parent_file;
 214        xdemitcb_t ecb;
 215        struct combine_diff_state state;
 216        unsigned long sz;
 217
 218        if (!cnt)
 219                return; /* result deleted */
 220
 221        parent_file.ptr = grab_blob(parent, &sz);
 222        parent_file.size = sz;
 223        xpp.flags = XDF_NEED_MINIMAL;
 224        xecfg.ctxlen = 0;
 225        xecfg.flags = 0;
 226        ecb.outf = xdiff_outf;
 227        ecb.priv = &state;
 228        memset(&state, 0, sizeof(state));
 229        state.xm.consume = consume_line;
 230        state.nmask = nmask;
 231        state.sline = sline;
 232        state.lno = 1;
 233        state.num_parent = num_parent;
 234        state.n = n;
 235
 236        xdl_diff(&parent_file, result_file, &xpp, &xecfg, &ecb);
 237        free(parent_file.ptr);
 238
 239        /* Assign line numbers for this parent.
 240         *
 241         * sline[lno].p_lno[n] records the first line number
 242         * (counting from 1) for parent N if the final hunk display
 243         * started by showing sline[lno] (possibly showing the lost
 244         * lines attached to it first).
 245         */
 246        for (lno = 0,  p_lno = 1; lno <= cnt; lno++) {
 247                struct lline *ll;
 248                sline[lno].p_lno[n] = p_lno;
 249
 250                /* How many lines would this sline advance the p_lno? */
 251                ll = sline[lno].lost_head;
 252                while (ll) {
 253                        if (ll->parent_map & nmask)
 254                                p_lno++; /* '-' means parent had it */
 255                        ll = ll->next;
 256                }
 257                if (lno < cnt && !(sline[lno].flag & nmask))
 258                        p_lno++; /* no '+' means parent had it */
 259        }
 260        sline[lno].p_lno[n] = p_lno; /* trailer */
 261}
 262
 263static unsigned long context = 3;
 264static char combine_marker = '@';
 265
 266static int interesting(struct sline *sline, unsigned long all_mask)
 267{
 268        /* If some parents lost lines here, or if we have added to
 269         * some parent, it is interesting.
 270         */
 271        return ((sline->flag & all_mask) || sline->lost_head);
 272}
 273
 274static unsigned long adjust_hunk_tail(struct sline *sline,
 275                                      unsigned long all_mask,
 276                                      unsigned long hunk_begin,
 277                                      unsigned long i)
 278{
 279        /* i points at the first uninteresting line.  If the last line
 280         * of the hunk was interesting only because it has some
 281         * deletion, then it is not all that interesting for the
 282         * purpose of giving trailing context lines.  This is because
 283         * we output '-' line and then unmodified sline[i-1] itself in
 284         * that case which gives us one extra context line.
 285         */
 286        if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
 287                i--;
 288        return i;
 289}
 290
 291static unsigned long find_next(struct sline *sline,
 292                               unsigned long mark,
 293                               unsigned long i,
 294                               unsigned long cnt,
 295                               int uninteresting)
 296{
 297        /* We have examined up to i-1 and are about to look at i.
 298         * Find next interesting or uninteresting line.  Here,
 299         * "interesting" does not mean interesting(), but marked by
 300         * the give_context() function below (i.e. it includes context
 301         * lines that are not interesting to interesting() function
 302         * that are surrounded by interesting() ones.
 303         */
 304        while (i <= cnt)
 305                if (uninteresting
 306                    ? !(sline[i].flag & mark)
 307                    : (sline[i].flag & mark))
 308                        return i;
 309                else
 310                        i++;
 311        return i;
 312}
 313
 314static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
 315{
 316        unsigned long all_mask = (1UL<<num_parent) - 1;
 317        unsigned long mark = (1UL<<num_parent);
 318        unsigned long i;
 319
 320        /* Two groups of interesting lines may have a short gap of
 321         * unintersting lines.  Connect such groups to give them a
 322         * bit of context.
 323         *
 324         * We first start from what the interesting() function says,
 325         * and mark them with "mark", and paint context lines with the
 326         * mark.  So interesting() would still say false for such context
 327         * lines but they are treated as "interesting" in the end.
 328         */
 329        i = find_next(sline, mark, 0, cnt, 0);
 330        if (cnt < i)
 331                return 0;
 332
 333        while (i <= cnt) {
 334                unsigned long j = (context < i) ? (i - context) : 0;
 335                unsigned long k;
 336
 337                /* Paint a few lines before the first interesting line. */
 338                while (j < i)
 339                        sline[j++].flag |= mark;
 340
 341        again:
 342                /* we know up to i is to be included.  where does the
 343                 * next uninteresting one start?
 344                 */
 345                j = find_next(sline, mark, i, cnt, 1);
 346                if (cnt < j)
 347                        break; /* the rest are all interesting */
 348
 349                /* lookahead context lines */
 350                k = find_next(sline, mark, j, cnt, 0);
 351                j = adjust_hunk_tail(sline, all_mask, i, j);
 352
 353                if (k < j + context) {
 354                        /* k is interesting and [j,k) are not, but
 355                         * paint them interesting because the gap is small.
 356                         */
 357                        while (j < k)
 358                                sline[j++].flag |= mark;
 359                        i = k;
 360                        goto again;
 361                }
 362
 363                /* j is the first uninteresting line and there is
 364                 * no overlap beyond it within context lines.  Paint
 365                 * the trailing edge a bit.
 366                 */
 367                i = k;
 368                k = (j + context < cnt+1) ? j + context : cnt+1;
 369                while (j < k)
 370                        sline[j++].flag |= mark;
 371        }
 372        return 1;
 373}
 374
 375static int make_hunks(struct sline *sline, unsigned long cnt,
 376                       int num_parent, int dense)
 377{
 378        unsigned long all_mask = (1UL<<num_parent) - 1;
 379        unsigned long mark = (1UL<<num_parent);
 380        unsigned long i;
 381        int has_interesting = 0;
 382
 383        for (i = 0; i <= cnt; i++) {
 384                if (interesting(&sline[i], all_mask))
 385                        sline[i].flag |= mark;
 386                else
 387                        sline[i].flag &= ~mark;
 388        }
 389        if (!dense)
 390                return give_context(sline, cnt, num_parent);
 391
 392        /* Look at each hunk, and if we have changes from only one
 393         * parent, or the changes are the same from all but one
 394         * parent, mark that uninteresting.
 395         */
 396        i = 0;
 397        while (i <= cnt) {
 398                unsigned long j, hunk_begin, hunk_end;
 399                unsigned long same_diff;
 400                while (i <= cnt && !(sline[i].flag & mark))
 401                        i++;
 402                if (cnt < i)
 403                        break; /* No more interesting hunks */
 404                hunk_begin = i;
 405                for (j = i + 1; j <= cnt; j++) {
 406                        if (!(sline[j].flag & mark)) {
 407                                /* Look beyond the end to see if there
 408                                 * is an interesting line after this
 409                                 * hunk within context span.
 410                                 */
 411                                unsigned long la; /* lookahead */
 412                                int contin = 0;
 413                                la = adjust_hunk_tail(sline, all_mask,
 414                                                     hunk_begin, j);
 415                                la = (la + context < cnt + 1) ?
 416                                        (la + context) : cnt + 1;
 417                                while (j <= --la) {
 418                                        if (sline[la].flag & mark) {
 419                                                contin = 1;
 420                                                break;
 421                                        }
 422                                }
 423                                if (!contin)
 424                                        break;
 425                                j = la;
 426                        }
 427                }
 428                hunk_end = j;
 429
 430                /* [i..hunk_end) are interesting.  Now is it really
 431                 * interesting?  We check if there are only two versions
 432                 * and the result matches one of them.  That is, we look
 433                 * at:
 434                 *   (+) line, which records lines added to which parents;
 435                 *       this line appears in the result.
 436                 *   (-) line, which records from what parents the line
 437                 *       was removed; this line does not appear in the result.
 438                 * then check the set of parents the result has difference
 439                 * from, from all lines.  If there are lines that has
 440                 * different set of parents that the result has differences
 441                 * from, that means we have more than two versions.
 442                 *
 443                 * Even when we have only two versions, if the result does
 444                 * not match any of the parents, the it should be considered
 445                 * interesting.  In such a case, we would have all '+' line.
 446                 * After passing the above "two versions" test, that would
 447                 * appear as "the same set of parents" to be "all parents".
 448                 */
 449                same_diff = 0;
 450                has_interesting = 0;
 451                for (j = i; j < hunk_end && !has_interesting; j++) {
 452                        unsigned long this_diff = sline[j].flag & all_mask;
 453                        struct lline *ll = sline[j].lost_head;
 454                        if (this_diff) {
 455                                /* This has some changes.  Is it the
 456                                 * same as others?
 457                                 */
 458                                if (!same_diff)
 459                                        same_diff = this_diff;
 460                                else if (same_diff != this_diff) {
 461                                        has_interesting = 1;
 462                                        break;
 463                                }
 464                        }
 465                        while (ll && !has_interesting) {
 466                                /* Lost this line from these parents;
 467                                 * who are they?  Are they the same?
 468                                 */
 469                                this_diff = ll->parent_map;
 470                                if (!same_diff)
 471                                        same_diff = this_diff;
 472                                else if (same_diff != this_diff) {
 473                                        has_interesting = 1;
 474                                }
 475                                ll = ll->next;
 476                        }
 477                }
 478
 479                if (!has_interesting && same_diff != all_mask) {
 480                        /* This hunk is not that interesting after all */
 481                        for (j = hunk_begin; j < hunk_end; j++)
 482                                sline[j].flag &= ~mark;
 483                }
 484                i = hunk_end;
 485        }
 486
 487        has_interesting = give_context(sline, cnt, num_parent);
 488        return has_interesting;
 489}
 490
 491static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, unsigned long cnt, int n)
 492{
 493        l0 = sline[l0].p_lno[n];
 494        l1 = sline[l1].p_lno[n];
 495        printf(" -%lu,%lu", l0, l1-l0);
 496}
 497
 498static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent)
 499{
 500        unsigned long mark = (1UL<<num_parent);
 501        int i;
 502        unsigned long lno = 0;
 503
 504        if (!cnt)
 505                return; /* result deleted */
 506
 507        while (1) {
 508                struct sline *sl = &sline[lno];
 509                unsigned long hunk_end;
 510                unsigned long rlines;
 511                while (lno <= cnt && !(sline[lno].flag & mark))
 512                        lno++;
 513                if (cnt < lno)
 514                        break;
 515                else {
 516                        for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
 517                                if (!(sline[hunk_end].flag & mark))
 518                                        break;
 519                }
 520                rlines = hunk_end - lno;
 521                if (cnt < hunk_end)
 522                        rlines--; /* pointing at the last delete hunk */
 523                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 524                for (i = 0; i < num_parent; i++)
 525                        show_parent_lno(sline, lno, hunk_end, cnt, i);
 526                printf(" +%lu,%lu ", lno+1, rlines);
 527                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 528                putchar('\n');
 529                while (lno < hunk_end) {
 530                        struct lline *ll;
 531                        int j;
 532                        unsigned long p_mask;
 533                        sl = &sline[lno++];
 534                        ll = sl->lost_head;
 535                        while (ll) {
 536                                for (j = 0; j < num_parent; j++) {
 537                                        if (ll->parent_map & (1UL<<j))
 538                                                putchar('-');
 539                                        else
 540                                                putchar(' ');
 541                                }
 542                                puts(ll->line);
 543                                ll = ll->next;
 544                        }
 545                        if (cnt < lno)
 546                                break;
 547                        p_mask = 1;
 548                        for (j = 0; j < num_parent; j++) {
 549                                if (p_mask & sl->flag)
 550                                        putchar('+');
 551                                else
 552                                        putchar(' ');
 553                                p_mask <<= 1;
 554                        }
 555                        printf("%.*s\n", sl->len, sl->bol);
 556                }
 557        }
 558}
 559
 560static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
 561                               int i, int j)
 562{
 563        /* We have already examined parent j and we know parent i
 564         * and parent j are the same, so reuse the combined result
 565         * of parent j for parent i.
 566         */
 567        unsigned long lno, imask, jmask;
 568        imask = (1UL<<i);
 569        jmask = (1UL<<j);
 570
 571        for (lno = 0; lno <= cnt; lno++) {
 572                struct lline *ll = sline->lost_head;
 573                sline->p_lno[i] = sline->p_lno[j];
 574                while (ll) {
 575                        if (ll->parent_map & jmask)
 576                                ll->parent_map |= imask;
 577                        ll = ll->next;
 578                }
 579                if (sline->flag & jmask)
 580                        sline->flag |= imask;
 581                sline++;
 582        }
 583        /* the overall size of the file (sline[cnt]) */
 584        sline->p_lno[i] = sline->p_lno[j];
 585}
 586
 587static int show_patch_diff(struct combine_diff_path *elem, int num_parent,
 588                           int dense, const char *header,
 589                           struct diff_options *opt)
 590{
 591        unsigned long result_size, cnt, lno;
 592        char *result, *cp;
 593        struct sline *sline; /* survived lines */
 594        int mode_differs = 0;
 595        int i, show_hunks, shown_header = 0;
 596        int working_tree_file = !memcmp(elem->sha1, null_sha1, 20);
 597        int abbrev = opt->full_index ? 40 : DEFAULT_ABBREV;
 598        mmfile_t result_file;
 599
 600        /* Read the result of merge first */
 601        if (!working_tree_file)
 602                result = grab_blob(elem->sha1, &result_size);
 603        else {
 604                /* Used by diff-tree to read from the working tree */
 605                struct stat st;
 606                int fd;
 607                if (0 <= (fd = open(elem->path, O_RDONLY)) &&
 608                    !fstat(fd, &st)) {
 609                        int len = st.st_size;
 610                        int cnt = 0;
 611
 612                        elem->mode = canon_mode(st.st_mode);
 613                        result_size = len;
 614                        result = xmalloc(len + 1);
 615                        while (cnt < len) {
 616                                int done = xread(fd, result+cnt, len-cnt);
 617                                if (done == 0)
 618                                        break;
 619                                if (done < 0)
 620                                        die("read error '%s'", elem->path);
 621                                cnt += done;
 622                        }
 623                        result[len] = 0;
 624                }
 625                else {
 626                        /* deleted file */
 627                        result_size = 0;
 628                        elem->mode = 0;
 629                        result = xmalloc(1);
 630                        result[0] = 0;
 631                }
 632                if (0 <= fd)
 633                        close(fd);
 634        }
 635
 636        for (cnt = 0, cp = result; cp - result < result_size; cp++) {
 637                if (*cp == '\n')
 638                        cnt++;
 639        }
 640        if (result_size && result[result_size-1] != '\n')
 641                cnt++; /* incomplete line */
 642
 643        sline = xcalloc(cnt+2, sizeof(*sline));
 644        sline[0].bol = result;
 645        for (lno = 0; lno <= cnt + 1; lno++) {
 646                sline[lno].lost_tail = &sline[lno].lost_head;
 647                sline[lno].flag = 0;
 648        }
 649        for (lno = 0, cp = result; cp - result < result_size; cp++) {
 650                if (*cp == '\n') {
 651                        sline[lno].len = cp - sline[lno].bol;
 652                        lno++;
 653                        if (lno < cnt)
 654                                sline[lno].bol = cp + 1;
 655                }
 656        }
 657        if (result_size && result[result_size-1] != '\n')
 658                sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
 659
 660        result_file.ptr = result;
 661        result_file.size = result_size;
 662
 663        /* Even p_lno[cnt+1] is valid -- that is for the end line number
 664         * for deletion hunk at the end.
 665         */
 666        sline[0].p_lno = xcalloc((cnt+2) * num_parent, sizeof(unsigned long));
 667        for (lno = 0; lno <= cnt; lno++)
 668                sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
 669
 670        for (i = 0; i < num_parent; i++) {
 671                int j;
 672                for (j = 0; j < i; j++) {
 673                        if (!memcmp(elem->parent[i].sha1,
 674                                    elem->parent[j].sha1, 20)) {
 675                                reuse_combine_diff(sline, cnt, i, j);
 676                                break;
 677                        }
 678                }
 679                if (i <= j)
 680                        combine_diff(elem->parent[i].sha1, &result_file, sline,
 681                                     cnt, i, num_parent);
 682                if (elem->parent[i].mode != elem->mode)
 683                        mode_differs = 1;
 684        }
 685
 686        show_hunks = make_hunks(sline, cnt, num_parent, dense);
 687
 688        if (show_hunks || mode_differs || working_tree_file) {
 689                const char *abb;
 690
 691                if (header) {
 692                        shown_header++;
 693                        printf("%s%c", header, opt->line_termination);
 694                }
 695                printf("diff --%s ", dense ? "cc" : "combined");
 696                if (quote_c_style(elem->path, NULL, NULL, 0))
 697                        quote_c_style(elem->path, NULL, stdout, 0);
 698                else
 699                        printf("%s", elem->path);
 700                putchar('\n');
 701                printf("index ");
 702                for (i = 0; i < num_parent; i++) {
 703                        abb = find_unique_abbrev(elem->parent[i].sha1,
 704                                                 abbrev);
 705                        printf("%s%s", i ? "," : "", abb);
 706                }
 707                abb = find_unique_abbrev(elem->sha1, abbrev);
 708                printf("..%s\n", abb);
 709
 710                if (mode_differs) {
 711                        int added = !!elem->mode;
 712                        for (i = 0; added && i < num_parent; i++)
 713                                if (elem->parent[i].status !=
 714                                    DIFF_STATUS_ADDED)
 715                                        added = 0;
 716                        if (added)
 717                                printf("new file mode %06o", elem->mode);
 718                        else {
 719                                if (!elem->mode)
 720                                        printf("deleted file ");
 721                                printf("mode ");
 722                                for (i = 0; i < num_parent; i++) {
 723                                        printf("%s%06o", i ? "," : "",
 724                                               elem->parent[i].mode);
 725                                }
 726                                if (elem->mode)
 727                                        printf("..%06o", elem->mode);
 728                        }
 729                        putchar('\n');
 730                }
 731                dump_sline(sline, cnt, num_parent);
 732        }
 733        free(result);
 734
 735        for (i = 0; i < cnt; i++) {
 736                if (sline[i].lost_head) {
 737                        struct lline *ll = sline[i].lost_head;
 738                        while (ll) {
 739                                struct lline *tmp = ll;
 740                                ll = ll->next;
 741                                free(tmp);
 742                        }
 743                }
 744        }
 745        free(sline[0].p_lno);
 746        free(sline);
 747        return shown_header;
 748}
 749
 750#define COLONS "::::::::::::::::::::::::::::::::"
 751
 752static void show_raw_diff(struct combine_diff_path *p, int num_parent, const char *header, struct diff_options *opt)
 753{
 754        int i, offset;
 755        const char *prefix;
 756        int line_termination, inter_name_termination;
 757
 758        line_termination = opt->line_termination;
 759        inter_name_termination = '\t';
 760        if (!line_termination)
 761                inter_name_termination = 0;
 762
 763        if (header)
 764                printf("%s%c", header, line_termination);
 765
 766        if (opt->output_format == DIFF_FORMAT_RAW) {
 767                offset = strlen(COLONS) - num_parent;
 768                if (offset < 0)
 769                        offset = 0;
 770                prefix = COLONS + offset;
 771
 772                /* Show the modes */
 773                for (i = 0; i < num_parent; i++) {
 774                        printf("%s%06o", prefix, p->parent[i].mode);
 775                        prefix = " ";
 776                }
 777                printf("%s%06o", prefix, p->mode);
 778
 779                /* Show sha1's */
 780                for (i = 0; i < num_parent; i++)
 781                        printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
 782                                                         opt->abbrev));
 783                printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
 784        }
 785
 786        if (opt->output_format == DIFF_FORMAT_RAW ||
 787            opt->output_format == DIFF_FORMAT_NAME_STATUS) {
 788                for (i = 0; i < num_parent; i++)
 789                        putchar(p->parent[i].status);
 790                putchar(inter_name_termination);
 791        }
 792
 793        if (line_termination) {
 794                if (quote_c_style(p->path, NULL, NULL, 0))
 795                        quote_c_style(p->path, NULL, stdout, 0);
 796                else
 797                        printf("%s", p->path);
 798                putchar(line_termination);
 799        }
 800        else {
 801                printf("%s%c", p->path, line_termination);
 802        }
 803}
 804
 805int show_combined_diff(struct combine_diff_path *p,
 806                       int num_parent,
 807                       int dense,
 808                       const char *header,
 809                       struct diff_options *opt)
 810{
 811        if (!p->len)
 812                return 0;
 813        switch (opt->output_format) {
 814        case DIFF_FORMAT_RAW:
 815        case DIFF_FORMAT_NAME_STATUS:
 816        case DIFF_FORMAT_NAME:
 817                show_raw_diff(p, num_parent, header, opt);
 818                return 1;
 819
 820        default:
 821        case DIFF_FORMAT_PATCH:
 822                return show_patch_diff(p, num_parent, dense, header, opt);
 823        }
 824}
 825
 826const char *diff_tree_combined_merge(const unsigned char *sha1,
 827                             const char *header, int dense,
 828                             struct diff_options *opt)
 829{
 830        struct commit *commit = lookup_commit(sha1);
 831        struct diff_options diffopts;
 832        struct commit_list *parents;
 833        struct combine_diff_path *p, *paths = NULL;
 834        int num_parent, i, num_paths;
 835
 836        diffopts = *opt;
 837        diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
 838        diffopts.with_raw = 0;
 839        diffopts.recursive = 1;
 840
 841        /* count parents */
 842        for (parents = commit->parents, num_parent = 0;
 843             parents;
 844             parents = parents->next, num_parent++)
 845                ; /* nothing */
 846
 847        /* find set of paths that everybody touches */
 848        for (parents = commit->parents, i = 0;
 849             parents;
 850             parents = parents->next, i++) {
 851                struct commit *parent = parents->item;
 852                diff_tree_sha1(parent->object.sha1, commit->object.sha1, "",
 853                               &diffopts);
 854                diffcore_std(&diffopts);
 855                paths = intersect_paths(paths, i, num_parent);
 856                diff_flush(&diffopts);
 857        }
 858
 859        /* find out surviving paths */
 860        for (num_paths = 0, p = paths; p; p = p->next) {
 861                if (p->len)
 862                        num_paths++;
 863        }
 864        if (num_paths) {
 865                if (opt->with_raw) {
 866                        int saved_format = opt->output_format;
 867                        opt->output_format = DIFF_FORMAT_RAW;
 868                        for (p = paths; p; p = p->next) {
 869                                if (show_combined_diff(p, num_parent, dense,
 870                                                       header, opt))
 871                                        header = NULL;
 872                        }
 873                        opt->output_format = saved_format;
 874                        putchar(opt->line_termination);
 875                }
 876                for (p = paths; p; p = p->next) {
 877                        if (show_combined_diff(p, num_parent, dense,
 878                                               header, opt))
 879                                header = NULL;
 880                }
 881        }
 882
 883        /* Clean things up */
 884        while (paths) {
 885                struct combine_diff_path *tmp = paths;
 886                paths = paths->next;
 887                free(tmp);
 888        }
 889        return header;
 890}