combine-diff.con commit Makefile: Set USE_PIC on x86-64 (c35ebc9)
   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 "log-tree.h"
   9
  10static int uninteresting(struct diff_filepair *p)
  11{
  12        if (diff_unmodified_pair(p))
  13                return 1;
  14        return 0;
  15}
  16
  17static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
  18{
  19        struct diff_queue_struct *q = &diff_queued_diff;
  20        struct combine_diff_path *p;
  21        int i;
  22
  23        if (!n) {
  24                struct combine_diff_path *list = NULL, **tail = &list;
  25                for (i = 0; i < q->nr; i++) {
  26                        int len;
  27                        const char *path;
  28                        if (uninteresting(q->queue[i]))
  29                                continue;
  30                        path = q->queue[i]->two->path;
  31                        len = strlen(path);
  32                        p = xmalloc(combine_diff_path_size(num_parent, len));
  33                        p->path = (char*) &(p->parent[num_parent]);
  34                        memcpy(p->path, path, len);
  35                        p->path[len] = 0;
  36                        p->len = len;
  37                        p->next = NULL;
  38                        memset(p->parent, 0,
  39                               sizeof(p->parent[0]) * num_parent);
  40
  41                        memcpy(p->sha1, q->queue[i]->two->sha1, 20);
  42                        p->mode = q->queue[i]->two->mode;
  43                        memcpy(p->parent[n].sha1, q->queue[i]->one->sha1, 20);
  44                        p->parent[n].mode = q->queue[i]->one->mode;
  45                        p->parent[n].status = q->queue[i]->status;
  46                        *tail = p;
  47                        tail = &p->next;
  48                }
  49                return list;
  50        }
  51
  52        for (p = curr; p; p = p->next) {
  53                int found = 0;
  54                if (!p->len)
  55                        continue;
  56                for (i = 0; i < q->nr; i++) {
  57                        const char *path;
  58                        int len;
  59
  60                        if (uninteresting(q->queue[i]))
  61                                continue;
  62                        path = q->queue[i]->two->path;
  63                        len = strlen(path);
  64                        if (len == p->len && !memcmp(path, p->path, len)) {
  65                                found = 1;
  66                                memcpy(p->parent[n].sha1,
  67                                       q->queue[i]->one->sha1, 20);
  68                                p->parent[n].mode = q->queue[i]->one->mode;
  69                                p->parent[n].status = q->queue[i]->status;
  70                                break;
  71                        }
  72                }
  73                if (!found)
  74                        p->len = 0;
  75        }
  76        return curr;
  77}
  78
  79/* Lines lost from parent */
  80struct lline {
  81        struct lline *next;
  82        int len;
  83        unsigned long parent_map;
  84        char line[FLEX_ARRAY];
  85};
  86
  87/* Lines surviving in the merge result */
  88struct sline {
  89        struct lline *lost_head, **lost_tail;
  90        char *bol;
  91        int len;
  92        /* bit 0 up to (N-1) are on if the parent has this line (i.e.
  93         * we did not change it).
  94         * bit N is used for "interesting" lines, including context.
  95         */
  96        unsigned long flag;
  97        unsigned long *p_lno;
  98};
  99
 100static char *grab_blob(const unsigned char *sha1, unsigned long *size)
 101{
 102        char *blob;
 103        char type[20];
 104        if (!memcmp(sha1, null_sha1, 20)) {
 105                /* deleted blob */
 106                *size = 0;
 107                return xcalloc(1, 1);
 108        }
 109        blob = read_sha1_file(sha1, type, size);
 110        if (strcmp(type, blob_type))
 111                die("object '%s' is not a blob!", sha1_to_hex(sha1));
 112        return blob;
 113}
 114
 115static void append_lost(struct sline *sline, int n, const char *line, int len)
 116{
 117        struct lline *lline;
 118        unsigned long this_mask = (1UL<<n);
 119        if (line[len-1] == '\n')
 120                len--;
 121
 122        /* Check to see if we can squash things */
 123        if (sline->lost_head) {
 124                struct lline *last_one = NULL;
 125                /* We cannot squash it with earlier one */
 126                for (lline = sline->lost_head;
 127                     lline;
 128                     lline = lline->next)
 129                        if (lline->parent_map & this_mask)
 130                                last_one = lline;
 131                lline = last_one ? last_one->next : sline->lost_head;
 132                while (lline) {
 133                        if (lline->len == len &&
 134                            !memcmp(lline->line, line, len)) {
 135                                lline->parent_map |= this_mask;
 136                                return;
 137                        }
 138                        lline = lline->next;
 139                }
 140        }
 141
 142        lline = xmalloc(sizeof(*lline) + len + 1);
 143        lline->len = len;
 144        lline->next = NULL;
 145        lline->parent_map = this_mask;
 146        memcpy(lline->line, line, len);
 147        lline->line[len] = 0;
 148        *sline->lost_tail = lline;
 149        sline->lost_tail = &lline->next;
 150}
 151
 152struct combine_diff_state {
 153        struct xdiff_emit_state xm;
 154
 155        unsigned int lno;
 156        int ob, on, nb, nn;
 157        unsigned long nmask;
 158        int num_parent;
 159        int n;
 160        struct sline *sline;
 161        struct sline *lost_bucket;
 162};
 163
 164static void consume_line(void *state_, char *line, unsigned long len)
 165{
 166        struct combine_diff_state *state = state_;
 167        if (5 < len && !memcmp("@@ -", line, 4)) {
 168                if (parse_hunk_header(line, len,
 169                                      &state->ob, &state->on,
 170                                      &state->nb, &state->nn))
 171                        return;
 172                state->lno = state->nb;
 173                if (!state->nb)
 174                        /* @@ -1,2 +0,0 @@ to remove the
 175                         * first two lines...
 176                         */
 177                        state->nb = 1;
 178                if (state->nn == 0)
 179                        /* @@ -X,Y +N,0 @@ removed Y lines
 180                         * that would have come *after* line N
 181                         * in the result.  Our lost buckets hang
 182                         * to the line after the removed lines,
 183                         */
 184                        state->lost_bucket = &state->sline[state->nb];
 185                else
 186                        state->lost_bucket = &state->sline[state->nb-1];
 187                if (!state->sline[state->nb-1].p_lno)
 188                        state->sline[state->nb-1].p_lno =
 189                                xcalloc(state->num_parent,
 190                                        sizeof(unsigned long));
 191                state->sline[state->nb-1].p_lno[state->n] = state->ob;
 192                return;
 193        }
 194        if (!state->lost_bucket)
 195                return; /* not in any hunk yet */
 196        switch (line[0]) {
 197        case '-':
 198                append_lost(state->lost_bucket, state->n, line+1, len-1);
 199                break;
 200        case '+':
 201                state->sline[state->lno-1].flag |= state->nmask;
 202                state->lno++;
 203                break;
 204        }
 205}
 206
 207static void combine_diff(const unsigned char *parent, mmfile_t *result_file,
 208                         struct sline *sline, unsigned int cnt, int n,
 209                         int num_parent)
 210{
 211        unsigned int p_lno, lno;
 212        unsigned long nmask = (1UL << n);
 213        xpparam_t xpp;
 214        xdemitconf_t xecfg;
 215        mmfile_t parent_file;
 216        xdemitcb_t ecb;
 217        struct combine_diff_state state;
 218        unsigned long sz;
 219
 220        if (!cnt)
 221                return; /* result deleted */
 222
 223        parent_file.ptr = grab_blob(parent, &sz);
 224        parent_file.size = sz;
 225        xpp.flags = XDF_NEED_MINIMAL;
 226        xecfg.ctxlen = 0;
 227        xecfg.flags = 0;
 228        ecb.outf = xdiff_outf;
 229        ecb.priv = &state;
 230        memset(&state, 0, sizeof(state));
 231        state.xm.consume = consume_line;
 232        state.nmask = nmask;
 233        state.sline = sline;
 234        state.lno = 1;
 235        state.num_parent = num_parent;
 236        state.n = n;
 237
 238        xdl_diff(&parent_file, result_file, &xpp, &xecfg, &ecb);
 239        free(parent_file.ptr);
 240
 241        /* Assign line numbers for this parent.
 242         *
 243         * sline[lno].p_lno[n] records the first line number
 244         * (counting from 1) for parent N if the final hunk display
 245         * started by showing sline[lno] (possibly showing the lost
 246         * lines attached to it first).
 247         */
 248        for (lno = 0,  p_lno = 1; lno <= cnt; lno++) {
 249                struct lline *ll;
 250                sline[lno].p_lno[n] = p_lno;
 251
 252                /* How many lines would this sline advance the p_lno? */
 253                ll = sline[lno].lost_head;
 254                while (ll) {
 255                        if (ll->parent_map & nmask)
 256                                p_lno++; /* '-' means parent had it */
 257                        ll = ll->next;
 258                }
 259                if (lno < cnt && !(sline[lno].flag & nmask))
 260                        p_lno++; /* no '+' means parent had it */
 261        }
 262        sline[lno].p_lno[n] = p_lno; /* trailer */
 263}
 264
 265static unsigned long context = 3;
 266static char combine_marker = '@';
 267
 268static int interesting(struct sline *sline, unsigned long all_mask)
 269{
 270        /* If some parents lost lines here, or if we have added to
 271         * some parent, it is interesting.
 272         */
 273        return ((sline->flag & all_mask) || sline->lost_head);
 274}
 275
 276static unsigned long adjust_hunk_tail(struct sline *sline,
 277                                      unsigned long all_mask,
 278                                      unsigned long hunk_begin,
 279                                      unsigned long i)
 280{
 281        /* i points at the first uninteresting line.  If the last line
 282         * of the hunk was interesting only because it has some
 283         * deletion, then it is not all that interesting for the
 284         * purpose of giving trailing context lines.  This is because
 285         * we output '-' line and then unmodified sline[i-1] itself in
 286         * that case which gives us one extra context line.
 287         */
 288        if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
 289                i--;
 290        return i;
 291}
 292
 293static unsigned long find_next(struct sline *sline,
 294                               unsigned long mark,
 295                               unsigned long i,
 296                               unsigned long cnt,
 297                               int look_for_uninteresting)
 298{
 299        /* We have examined up to i-1 and are about to look at i.
 300         * Find next interesting or uninteresting line.  Here,
 301         * "interesting" does not mean interesting(), but marked by
 302         * the give_context() function below (i.e. it includes context
 303         * lines that are not interesting to interesting() function
 304         * that are surrounded by interesting() ones.
 305         */
 306        while (i <= cnt)
 307                if (look_for_uninteresting
 308                    ? !(sline[i].flag & mark)
 309                    : (sline[i].flag & mark))
 310                        return i;
 311                else
 312                        i++;
 313        return i;
 314}
 315
 316static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
 317{
 318        unsigned long all_mask = (1UL<<num_parent) - 1;
 319        unsigned long mark = (1UL<<num_parent);
 320        unsigned long i;
 321
 322        /* Two groups of interesting lines may have a short gap of
 323         * unintersting lines.  Connect such groups to give them a
 324         * bit of context.
 325         *
 326         * We first start from what the interesting() function says,
 327         * and mark them with "mark", and paint context lines with the
 328         * mark.  So interesting() would still say false for such context
 329         * lines but they are treated as "interesting" in the end.
 330         */
 331        i = find_next(sline, mark, 0, cnt, 0);
 332        if (cnt < i)
 333                return 0;
 334
 335        while (i <= cnt) {
 336                unsigned long j = (context < i) ? (i - context) : 0;
 337                unsigned long k;
 338
 339                /* Paint a few lines before the first interesting line. */
 340                while (j < i)
 341                        sline[j++].flag |= mark;
 342
 343        again:
 344                /* we know up to i is to be included.  where does the
 345                 * next uninteresting one start?
 346                 */
 347                j = find_next(sline, mark, i, cnt, 1);
 348                if (cnt < j)
 349                        break; /* the rest are all interesting */
 350
 351                /* lookahead context lines */
 352                k = find_next(sline, mark, j, cnt, 0);
 353                j = adjust_hunk_tail(sline, all_mask, i, j);
 354
 355                if (k < j + context) {
 356                        /* k is interesting and [j,k) are not, but
 357                         * paint them interesting because the gap is small.
 358                         */
 359                        while (j < k)
 360                                sline[j++].flag |= mark;
 361                        i = k;
 362                        goto again;
 363                }
 364
 365                /* j is the first uninteresting line and there is
 366                 * no overlap beyond it within context lines.  Paint
 367                 * the trailing edge a bit.
 368                 */
 369                i = k;
 370                k = (j + context < cnt+1) ? j + context : cnt+1;
 371                while (j < k)
 372                        sline[j++].flag |= mark;
 373        }
 374        return 1;
 375}
 376
 377static int make_hunks(struct sline *sline, unsigned long cnt,
 378                       int num_parent, int dense)
 379{
 380        unsigned long all_mask = (1UL<<num_parent) - 1;
 381        unsigned long mark = (1UL<<num_parent);
 382        unsigned long i;
 383        int has_interesting = 0;
 384
 385        for (i = 0; i <= cnt; i++) {
 386                if (interesting(&sline[i], all_mask))
 387                        sline[i].flag |= mark;
 388                else
 389                        sline[i].flag &= ~mark;
 390        }
 391        if (!dense)
 392                return give_context(sline, cnt, num_parent);
 393
 394        /* Look at each hunk, and if we have changes from only one
 395         * parent, or the changes are the same from all but one
 396         * parent, mark that uninteresting.
 397         */
 398        i = 0;
 399        while (i <= cnt) {
 400                unsigned long j, hunk_begin, hunk_end;
 401                unsigned long same_diff;
 402                while (i <= cnt && !(sline[i].flag & mark))
 403                        i++;
 404                if (cnt < i)
 405                        break; /* No more interesting hunks */
 406                hunk_begin = i;
 407                for (j = i + 1; j <= cnt; j++) {
 408                        if (!(sline[j].flag & mark)) {
 409                                /* Look beyond the end to see if there
 410                                 * is an interesting line after this
 411                                 * hunk within context span.
 412                                 */
 413                                unsigned long la; /* lookahead */
 414                                int contin = 0;
 415                                la = adjust_hunk_tail(sline, all_mask,
 416                                                     hunk_begin, j);
 417                                la = (la + context < cnt + 1) ?
 418                                        (la + context) : cnt + 1;
 419                                while (j <= --la) {
 420                                        if (sline[la].flag & mark) {
 421                                                contin = 1;
 422                                                break;
 423                                        }
 424                                }
 425                                if (!contin)
 426                                        break;
 427                                j = la;
 428                        }
 429                }
 430                hunk_end = j;
 431
 432                /* [i..hunk_end) are interesting.  Now is it really
 433                 * interesting?  We check if there are only two versions
 434                 * and the result matches one of them.  That is, we look
 435                 * at:
 436                 *   (+) line, which records lines added to which parents;
 437                 *       this line appears in the result.
 438                 *   (-) line, which records from what parents the line
 439                 *       was removed; this line does not appear in the result.
 440                 * then check the set of parents the result has difference
 441                 * from, from all lines.  If there are lines that has
 442                 * different set of parents that the result has differences
 443                 * from, that means we have more than two versions.
 444                 *
 445                 * Even when we have only two versions, if the result does
 446                 * not match any of the parents, the it should be considered
 447                 * interesting.  In such a case, we would have all '+' line.
 448                 * After passing the above "two versions" test, that would
 449                 * appear as "the same set of parents" to be "all parents".
 450                 */
 451                same_diff = 0;
 452                has_interesting = 0;
 453                for (j = i; j < hunk_end && !has_interesting; j++) {
 454                        unsigned long this_diff = sline[j].flag & all_mask;
 455                        struct lline *ll = sline[j].lost_head;
 456                        if (this_diff) {
 457                                /* This has some changes.  Is it the
 458                                 * same as others?
 459                                 */
 460                                if (!same_diff)
 461                                        same_diff = this_diff;
 462                                else if (same_diff != this_diff) {
 463                                        has_interesting = 1;
 464                                        break;
 465                                }
 466                        }
 467                        while (ll && !has_interesting) {
 468                                /* Lost this line from these parents;
 469                                 * who are they?  Are they the same?
 470                                 */
 471                                this_diff = ll->parent_map;
 472                                if (!same_diff)
 473                                        same_diff = this_diff;
 474                                else if (same_diff != this_diff) {
 475                                        has_interesting = 1;
 476                                }
 477                                ll = ll->next;
 478                        }
 479                }
 480
 481                if (!has_interesting && same_diff != all_mask) {
 482                        /* This hunk is not that interesting after all */
 483                        for (j = hunk_begin; j < hunk_end; j++)
 484                                sline[j].flag &= ~mark;
 485                }
 486                i = hunk_end;
 487        }
 488
 489        has_interesting = give_context(sline, cnt, num_parent);
 490        return has_interesting;
 491}
 492
 493static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, int n)
 494{
 495        l0 = sline[l0].p_lno[n];
 496        l1 = sline[l1].p_lno[n];
 497        printf(" -%lu,%lu", l0, l1-l0);
 498}
 499
 500static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent)
 501{
 502        unsigned long mark = (1UL<<num_parent);
 503        int i;
 504        unsigned long lno = 0;
 505
 506        if (!cnt)
 507                return; /* result deleted */
 508
 509        while (1) {
 510                struct sline *sl = &sline[lno];
 511                unsigned long hunk_end;
 512                unsigned long rlines;
 513                while (lno <= cnt && !(sline[lno].flag & mark))
 514                        lno++;
 515                if (cnt < lno)
 516                        break;
 517                else {
 518                        for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
 519                                if (!(sline[hunk_end].flag & mark))
 520                                        break;
 521                }
 522                rlines = hunk_end - lno;
 523                if (cnt < hunk_end)
 524                        rlines--; /* pointing at the last delete hunk */
 525                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 526                for (i = 0; i < num_parent; i++)
 527                        show_parent_lno(sline, lno, hunk_end, i);
 528                printf(" +%lu,%lu ", lno+1, rlines);
 529                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 530                putchar('\n');
 531                while (lno < hunk_end) {
 532                        struct lline *ll;
 533                        int j;
 534                        unsigned long p_mask;
 535                        sl = &sline[lno++];
 536                        ll = sl->lost_head;
 537                        while (ll) {
 538                                for (j = 0; j < num_parent; j++) {
 539                                        if (ll->parent_map & (1UL<<j))
 540                                                putchar('-');
 541                                        else
 542                                                putchar(' ');
 543                                }
 544                                puts(ll->line);
 545                                ll = ll->next;
 546                        }
 547                        if (cnt < lno)
 548                                break;
 549                        p_mask = 1;
 550                        for (j = 0; j < num_parent; j++) {
 551                                if (p_mask & sl->flag)
 552                                        putchar('+');
 553                                else
 554                                        putchar(' ');
 555                                p_mask <<= 1;
 556                        }
 557                        printf("%.*s\n", sl->len, sl->bol);
 558                }
 559        }
 560}
 561
 562static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
 563                               int i, int j)
 564{
 565        /* We have already examined parent j and we know parent i
 566         * and parent j are the same, so reuse the combined result
 567         * of parent j for parent i.
 568         */
 569        unsigned long lno, imask, jmask;
 570        imask = (1UL<<i);
 571        jmask = (1UL<<j);
 572
 573        for (lno = 0; lno <= cnt; lno++) {
 574                struct lline *ll = sline->lost_head;
 575                sline->p_lno[i] = sline->p_lno[j];
 576                while (ll) {
 577                        if (ll->parent_map & jmask)
 578                                ll->parent_map |= imask;
 579                        ll = ll->next;
 580                }
 581                if (sline->flag & jmask)
 582                        sline->flag |= imask;
 583                sline++;
 584        }
 585        /* the overall size of the file (sline[cnt]) */
 586        sline->p_lno[i] = sline->p_lno[j];
 587}
 588
 589static void dump_quoted_path(const char *prefix, const char *path)
 590{
 591        fputs(prefix, stdout);
 592        if (quote_c_style(path, NULL, NULL, 0))
 593                quote_c_style(path, NULL, stdout, 0);
 594        else
 595                printf("%s", path);
 596        putchar('\n');
 597}
 598
 599static int show_patch_diff(struct combine_diff_path *elem, int num_parent,
 600                           int dense, struct rev_info *rev)
 601{
 602        struct diff_options *opt = &rev->diffopt;
 603        unsigned long result_size, cnt, lno;
 604        char *result, *cp;
 605        struct sline *sline; /* survived lines */
 606        int mode_differs = 0;
 607        int i, show_hunks, shown_header = 0;
 608        int working_tree_file = !memcmp(elem->sha1, null_sha1, 20);
 609        int abbrev = opt->full_index ? 40 : DEFAULT_ABBREV;
 610        mmfile_t result_file;
 611
 612        context = opt->context;
 613        /* Read the result of merge first */
 614        if (!working_tree_file)
 615                result = grab_blob(elem->sha1, &result_size);
 616        else {
 617                /* Used by diff-tree to read from the working tree */
 618                struct stat st;
 619                int fd;
 620                if (0 <= (fd = open(elem->path, O_RDONLY)) &&
 621                    !fstat(fd, &st)) {
 622                        int len = st.st_size;
 623                        int sz = 0;
 624
 625                        elem->mode = canon_mode(st.st_mode);
 626                        result_size = len;
 627                        result = xmalloc(len + 1);
 628                        while (sz < len) {
 629                                int done = xread(fd, result+sz, len-sz);
 630                                if (done == 0)
 631                                        break;
 632                                if (done < 0)
 633                                        die("read error '%s'", elem->path);
 634                                sz += done;
 635                        }
 636                        result[len] = 0;
 637                }
 638                else {
 639                        /* deleted file */
 640                        result_size = 0;
 641                        elem->mode = 0;
 642                        result = xmalloc(1);
 643                        result[0] = 0;
 644                }
 645                if (0 <= fd)
 646                        close(fd);
 647        }
 648
 649        for (cnt = 0, cp = result; cp < result + result_size; cp++) {
 650                if (*cp == '\n')
 651                        cnt++;
 652        }
 653        if (result_size && result[result_size-1] != '\n')
 654                cnt++; /* incomplete line */
 655
 656        sline = xcalloc(cnt+2, sizeof(*sline));
 657        sline[0].bol = result;
 658        for (lno = 0; lno <= cnt + 1; lno++) {
 659                sline[lno].lost_tail = &sline[lno].lost_head;
 660                sline[lno].flag = 0;
 661        }
 662        for (lno = 0, cp = result; cp < result + result_size; cp++) {
 663                if (*cp == '\n') {
 664                        sline[lno].len = cp - sline[lno].bol;
 665                        lno++;
 666                        if (lno < cnt)
 667                                sline[lno].bol = cp + 1;
 668                }
 669        }
 670        if (result_size && result[result_size-1] != '\n')
 671                sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
 672
 673        result_file.ptr = result;
 674        result_file.size = result_size;
 675
 676        /* Even p_lno[cnt+1] is valid -- that is for the end line number
 677         * for deletion hunk at the end.
 678         */
 679        sline[0].p_lno = xcalloc((cnt+2) * num_parent, sizeof(unsigned long));
 680        for (lno = 0; lno <= cnt; lno++)
 681                sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
 682
 683        for (i = 0; i < num_parent; i++) {
 684                int j;
 685                for (j = 0; j < i; j++) {
 686                        if (!memcmp(elem->parent[i].sha1,
 687                                    elem->parent[j].sha1, 20)) {
 688                                reuse_combine_diff(sline, cnt, i, j);
 689                                break;
 690                        }
 691                }
 692                if (i <= j)
 693                        combine_diff(elem->parent[i].sha1, &result_file, sline,
 694                                     cnt, i, num_parent);
 695                if (elem->parent[i].mode != elem->mode)
 696                        mode_differs = 1;
 697        }
 698
 699        show_hunks = make_hunks(sline, cnt, num_parent, dense);
 700
 701        if (show_hunks || mode_differs || working_tree_file) {
 702                const char *abb;
 703
 704                if (rev->loginfo)
 705                        show_log(rev, rev->loginfo, "\n");
 706                dump_quoted_path(dense ? "diff --cc " : "diff --combined ", elem->path);
 707                printf("index ");
 708                for (i = 0; i < num_parent; i++) {
 709                        abb = find_unique_abbrev(elem->parent[i].sha1,
 710                                                 abbrev);
 711                        printf("%s%s", i ? "," : "", abb);
 712                }
 713                abb = find_unique_abbrev(elem->sha1, abbrev);
 714                printf("..%s\n", abb);
 715
 716                if (mode_differs) {
 717                        int added = !!elem->mode;
 718                        for (i = 0; added && i < num_parent; i++)
 719                                if (elem->parent[i].status !=
 720                                    DIFF_STATUS_ADDED)
 721                                        added = 0;
 722                        if (added)
 723                                printf("new file mode %06o", elem->mode);
 724                        else {
 725                                if (!elem->mode)
 726                                        printf("deleted file ");
 727                                printf("mode ");
 728                                for (i = 0; i < num_parent; i++) {
 729                                        printf("%s%06o", i ? "," : "",
 730                                               elem->parent[i].mode);
 731                                }
 732                                if (elem->mode)
 733                                        printf("..%06o", elem->mode);
 734                        }
 735                        putchar('\n');
 736                }
 737                dump_quoted_path("--- a/", elem->path);
 738                dump_quoted_path("+++ b/", elem->path);
 739                dump_sline(sline, cnt, num_parent);
 740        }
 741        free(result);
 742
 743        for (lno = 0; lno < cnt; lno++) {
 744                if (sline[lno].lost_head) {
 745                        struct lline *ll = sline[lno].lost_head;
 746                        while (ll) {
 747                                struct lline *tmp = ll;
 748                                ll = ll->next;
 749                                free(tmp);
 750                        }
 751                }
 752        }
 753        free(sline[0].p_lno);
 754        free(sline);
 755        return shown_header;
 756}
 757
 758#define COLONS "::::::::::::::::::::::::::::::::"
 759
 760static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct rev_info *rev)
 761{
 762        struct diff_options *opt = &rev->diffopt;
 763        int i, offset;
 764        const char *prefix;
 765        int line_termination, inter_name_termination;
 766
 767        line_termination = opt->line_termination;
 768        inter_name_termination = '\t';
 769        if (!line_termination)
 770                inter_name_termination = 0;
 771
 772        if (rev->loginfo)
 773                show_log(rev, rev->loginfo, "\n");
 774
 775        if (opt->output_format == DIFF_FORMAT_RAW) {
 776                offset = strlen(COLONS) - num_parent;
 777                if (offset < 0)
 778                        offset = 0;
 779                prefix = COLONS + offset;
 780
 781                /* Show the modes */
 782                for (i = 0; i < num_parent; i++) {
 783                        printf("%s%06o", prefix, p->parent[i].mode);
 784                        prefix = " ";
 785                }
 786                printf("%s%06o", prefix, p->mode);
 787
 788                /* Show sha1's */
 789                for (i = 0; i < num_parent; i++)
 790                        printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
 791                                                         opt->abbrev));
 792                printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
 793        }
 794
 795        if (opt->output_format == DIFF_FORMAT_RAW ||
 796            opt->output_format == DIFF_FORMAT_NAME_STATUS) {
 797                for (i = 0; i < num_parent; i++)
 798                        putchar(p->parent[i].status);
 799                putchar(inter_name_termination);
 800        }
 801
 802        if (line_termination) {
 803                if (quote_c_style(p->path, NULL, NULL, 0))
 804                        quote_c_style(p->path, NULL, stdout, 0);
 805                else
 806                        printf("%s", p->path);
 807                putchar(line_termination);
 808        }
 809        else {
 810                printf("%s%c", p->path, line_termination);
 811        }
 812}
 813
 814void show_combined_diff(struct combine_diff_path *p,
 815                       int num_parent,
 816                       int dense,
 817                       struct rev_info *rev)
 818{
 819        struct diff_options *opt = &rev->diffopt;
 820        if (!p->len)
 821                return;
 822        switch (opt->output_format) {
 823        case DIFF_FORMAT_RAW:
 824        case DIFF_FORMAT_NAME_STATUS:
 825        case DIFF_FORMAT_NAME:
 826                show_raw_diff(p, num_parent, rev);
 827                return;
 828        case DIFF_FORMAT_PATCH:
 829                show_patch_diff(p, num_parent, dense, rev);
 830                return;
 831        default:
 832                return;
 833        }
 834}
 835
 836void diff_tree_combined(const unsigned char *sha1,
 837                        const unsigned char parent[][20],
 838                        int num_parent,
 839                        int dense,
 840                        struct rev_info *rev)
 841{
 842        struct diff_options *opt = &rev->diffopt;
 843        struct diff_options diffopts;
 844        struct combine_diff_path *p, *paths = NULL;
 845        int i, num_paths;
 846        int do_diffstat;
 847
 848        do_diffstat = (opt->output_format == DIFF_FORMAT_DIFFSTAT ||
 849                       opt->with_stat);
 850        diffopts = *opt;
 851        diffopts.with_raw = 0;
 852        diffopts.with_stat = 0;
 853        diffopts.recursive = 1;
 854
 855        /* find set of paths that everybody touches */
 856        for (i = 0; i < num_parent; i++) {
 857                /* show stat against the first parent even
 858                 * when doing combined diff.
 859                 */
 860                if (i == 0 && do_diffstat)
 861                        diffopts.output_format = DIFF_FORMAT_DIFFSTAT;
 862                else
 863                        diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
 864                diff_tree_sha1(parent[i], sha1, "", &diffopts);
 865                diffcore_std(&diffopts);
 866                paths = intersect_paths(paths, i, num_parent);
 867
 868                if (do_diffstat && rev->loginfo)
 869                        show_log(rev, rev->loginfo,
 870                                 opt->with_stat ? "---\n" : "\n");
 871                diff_flush(&diffopts);
 872                if (opt->with_stat)
 873                        putchar('\n');
 874        }
 875
 876        /* find out surviving paths */
 877        for (num_paths = 0, p = paths; p; p = p->next) {
 878                if (p->len)
 879                        num_paths++;
 880        }
 881        if (num_paths) {
 882                if (opt->with_raw) {
 883                        int saved_format = opt->output_format;
 884                        opt->output_format = DIFF_FORMAT_RAW;
 885                        for (p = paths; p; p = p->next) {
 886                                show_combined_diff(p, num_parent, dense, rev);
 887                        }
 888                        opt->output_format = saved_format;
 889                        putchar(opt->line_termination);
 890                }
 891                for (p = paths; p; p = p->next) {
 892                        show_combined_diff(p, num_parent, dense, rev);
 893                }
 894        }
 895
 896        /* Clean things up */
 897        while (paths) {
 898                struct combine_diff_path *tmp = paths;
 899                paths = paths->next;
 900                free(tmp);
 901        }
 902}
 903
 904void diff_tree_combined_merge(const unsigned char *sha1,
 905                             int dense, struct rev_info *rev)
 906{
 907        int num_parent;
 908        const unsigned char (*parent)[20];
 909        struct commit *commit = lookup_commit(sha1);
 910        struct commit_list *parents;
 911
 912        /* count parents */
 913        for (parents = commit->parents, num_parent = 0;
 914             parents;
 915             parents = parents->next, num_parent++)
 916                ; /* nothing */
 917
 918        parent = xmalloc(num_parent * sizeof(*parent));
 919        for (parents = commit->parents, num_parent = 0;
 920             parents;
 921             parents = parents->next, num_parent++)
 922                memcpy(parent + num_parent, parents->item->object.sha1, 20);
 923        diff_tree_combined(sha1, parent, num_parent, dense, rev);
 924}