combine-diff.con commit refactor get_textconv to not require diff_filespec (3813e69)
   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#include "refs.h"
  10#include "userdiff.h"
  11
  12static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
  13{
  14        struct diff_queue_struct *q = &diff_queued_diff;
  15        struct combine_diff_path *p;
  16        int i;
  17
  18        if (!n) {
  19                struct combine_diff_path *list = NULL, **tail = &list;
  20                for (i = 0; i < q->nr; i++) {
  21                        int len;
  22                        const char *path;
  23                        if (diff_unmodified_pair(q->queue[i]))
  24                                continue;
  25                        path = q->queue[i]->two->path;
  26                        len = strlen(path);
  27                        p = xmalloc(combine_diff_path_size(num_parent, len));
  28                        p->path = (char *) &(p->parent[num_parent]);
  29                        memcpy(p->path, path, len);
  30                        p->path[len] = 0;
  31                        p->len = len;
  32                        p->next = NULL;
  33                        memset(p->parent, 0,
  34                               sizeof(p->parent[0]) * num_parent);
  35
  36                        hashcpy(p->sha1, q->queue[i]->two->sha1);
  37                        p->mode = q->queue[i]->two->mode;
  38                        hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
  39                        p->parent[n].mode = q->queue[i]->one->mode;
  40                        p->parent[n].status = q->queue[i]->status;
  41                        *tail = p;
  42                        tail = &p->next;
  43                }
  44                return list;
  45        }
  46
  47        for (p = curr; p; p = p->next) {
  48                int found = 0;
  49                if (!p->len)
  50                        continue;
  51                for (i = 0; i < q->nr; i++) {
  52                        const char *path;
  53                        int len;
  54
  55                        if (diff_unmodified_pair(q->queue[i]))
  56                                continue;
  57                        path = q->queue[i]->two->path;
  58                        len = strlen(path);
  59                        if (len == p->len && !memcmp(path, p->path, len)) {
  60                                found = 1;
  61                                hashcpy(p->parent[n].sha1, q->queue[i]->one->sha1);
  62                                p->parent[n].mode = q->queue[i]->one->mode;
  63                                p->parent[n].status = q->queue[i]->status;
  64                                break;
  65                        }
  66                }
  67                if (!found)
  68                        p->len = 0;
  69        }
  70        return curr;
  71}
  72
  73/* Lines lost from parent */
  74struct lline {
  75        struct lline *next;
  76        int len;
  77        unsigned long parent_map;
  78        char line[FLEX_ARRAY];
  79};
  80
  81/* Lines surviving in the merge result */
  82struct sline {
  83        struct lline *lost_head, **lost_tail;
  84        struct lline *next_lost;
  85        char *bol;
  86        int len;
  87        /* bit 0 up to (N-1) are on if the parent has this line (i.e.
  88         * we did not change it).
  89         * bit N is used for "interesting" lines, including context.
  90         * bit (N+1) is used for "do not show deletion before this".
  91         */
  92        unsigned long flag;
  93        unsigned long *p_lno;
  94};
  95
  96static char *grab_blob(const unsigned char *sha1, unsigned int mode, unsigned long *size)
  97{
  98        char *blob;
  99        enum object_type type;
 100
 101        if (S_ISGITLINK(mode)) {
 102                blob = xmalloc(100);
 103                *size = snprintf(blob, 100,
 104                                 "Subproject commit %s\n", sha1_to_hex(sha1));
 105        } else if (is_null_sha1(sha1)) {
 106                /* deleted blob */
 107                *size = 0;
 108                return xcalloc(1, 1);
 109        } else {
 110                blob = read_sha1_file(sha1, &type, size);
 111                if (type != OBJ_BLOB)
 112                        die("object '%s' is not a blob!", sha1_to_hex(sha1));
 113        }
 114        return blob;
 115}
 116
 117static void append_lost(struct sline *sline, int n, const char *line, int len)
 118{
 119        struct lline *lline;
 120        unsigned long this_mask = (1UL<<n);
 121        if (line[len-1] == '\n')
 122                len--;
 123
 124        /* Check to see if we can squash things */
 125        if (sline->lost_head) {
 126                lline = sline->next_lost;
 127                while (lline) {
 128                        if (lline->len == len &&
 129                            !memcmp(lline->line, line, len)) {
 130                                lline->parent_map |= this_mask;
 131                                sline->next_lost = lline->next;
 132                                return;
 133                        }
 134                        lline = lline->next;
 135                }
 136        }
 137
 138        lline = xmalloc(sizeof(*lline) + len + 1);
 139        lline->len = len;
 140        lline->next = NULL;
 141        lline->parent_map = this_mask;
 142        memcpy(lline->line, line, len);
 143        lline->line[len] = 0;
 144        *sline->lost_tail = lline;
 145        sline->lost_tail = &lline->next;
 146        sline->next_lost = NULL;
 147}
 148
 149struct combine_diff_state {
 150        unsigned int lno;
 151        int ob, on, nb, nn;
 152        unsigned long nmask;
 153        int num_parent;
 154        int n;
 155        struct sline *sline;
 156        struct sline *lost_bucket;
 157};
 158
 159static void consume_line(void *state_, char *line, unsigned long len)
 160{
 161        struct combine_diff_state *state = state_;
 162        if (5 < len && !memcmp("@@ -", line, 4)) {
 163                if (parse_hunk_header(line, len,
 164                                      &state->ob, &state->on,
 165                                      &state->nb, &state->nn))
 166                        return;
 167                state->lno = state->nb;
 168                if (state->nn == 0) {
 169                        /* @@ -X,Y +N,0 @@ removed Y lines
 170                         * that would have come *after* line N
 171                         * in the result.  Our lost buckets hang
 172                         * to the line after the removed lines,
 173                         *
 174                         * Note that this is correct even when N == 0,
 175                         * in which case the hunk removes the first
 176                         * line in the file.
 177                         */
 178                        state->lost_bucket = &state->sline[state->nb];
 179                        if (!state->nb)
 180                                state->nb = 1;
 181                } else {
 182                        state->lost_bucket = &state->sline[state->nb-1];
 183                }
 184                if (!state->sline[state->nb-1].p_lno)
 185                        state->sline[state->nb-1].p_lno =
 186                                xcalloc(state->num_parent,
 187                                        sizeof(unsigned long));
 188                state->sline[state->nb-1].p_lno[state->n] = state->ob;
 189                state->lost_bucket->next_lost = state->lost_bucket->lost_head;
 190                return;
 191        }
 192        if (!state->lost_bucket)
 193                return; /* not in any hunk yet */
 194        switch (line[0]) {
 195        case '-':
 196                append_lost(state->lost_bucket, state->n, line+1, len-1);
 197                break;
 198        case '+':
 199                state->sline[state->lno-1].flag |= state->nmask;
 200                state->lno++;
 201                break;
 202        }
 203}
 204
 205static void combine_diff(const unsigned char *parent, unsigned int mode,
 206                         mmfile_t *result_file,
 207                         struct sline *sline, unsigned int cnt, int n,
 208                         int num_parent, int result_deleted)
 209{
 210        unsigned int p_lno, lno;
 211        unsigned long nmask = (1UL << n);
 212        xpparam_t xpp;
 213        xdemitconf_t xecfg;
 214        mmfile_t parent_file;
 215        struct combine_diff_state state;
 216        unsigned long sz;
 217
 218        if (result_deleted)
 219                return; /* result deleted */
 220
 221        parent_file.ptr = grab_blob(parent, mode, &sz);
 222        parent_file.size = sz;
 223        memset(&xpp, 0, sizeof(xpp));
 224        xpp.flags = 0;
 225        memset(&xecfg, 0, sizeof(xecfg));
 226        memset(&state, 0, sizeof(state));
 227        state.nmask = nmask;
 228        state.sline = sline;
 229        state.lno = 1;
 230        state.num_parent = num_parent;
 231        state.n = n;
 232
 233        xdi_diff_outf(&parent_file, result_file, consume_line, &state,
 234                      &xpp, &xecfg);
 235        free(parent_file.ptr);
 236
 237        /* Assign line numbers for this parent.
 238         *
 239         * sline[lno].p_lno[n] records the first line number
 240         * (counting from 1) for parent N if the final hunk display
 241         * started by showing sline[lno] (possibly showing the lost
 242         * lines attached to it first).
 243         */
 244        for (lno = 0,  p_lno = 1; lno <= cnt; lno++) {
 245                struct lline *ll;
 246                sline[lno].p_lno[n] = p_lno;
 247
 248                /* How many lines would this sline advance the p_lno? */
 249                ll = sline[lno].lost_head;
 250                while (ll) {
 251                        if (ll->parent_map & nmask)
 252                                p_lno++; /* '-' means parent had it */
 253                        ll = ll->next;
 254                }
 255                if (lno < cnt && !(sline[lno].flag & nmask))
 256                        p_lno++; /* no '+' means parent had it */
 257        }
 258        sline[lno].p_lno[n] = p_lno; /* trailer */
 259}
 260
 261static unsigned long context = 3;
 262static char combine_marker = '@';
 263
 264static int interesting(struct sline *sline, unsigned long all_mask)
 265{
 266        /* If some parents lost lines here, or if we have added to
 267         * some parent, it is interesting.
 268         */
 269        return ((sline->flag & all_mask) || sline->lost_head);
 270}
 271
 272static unsigned long adjust_hunk_tail(struct sline *sline,
 273                                      unsigned long all_mask,
 274                                      unsigned long hunk_begin,
 275                                      unsigned long i)
 276{
 277        /* i points at the first uninteresting line.  If the last line
 278         * of the hunk was interesting only because it has some
 279         * deletion, then it is not all that interesting for the
 280         * purpose of giving trailing context lines.  This is because
 281         * we output '-' line and then unmodified sline[i-1] itself in
 282         * that case which gives us one extra context line.
 283         */
 284        if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
 285                i--;
 286        return i;
 287}
 288
 289static unsigned long find_next(struct sline *sline,
 290                               unsigned long mark,
 291                               unsigned long i,
 292                               unsigned long cnt,
 293                               int look_for_uninteresting)
 294{
 295        /* We have examined up to i-1 and are about to look at i.
 296         * Find next interesting or uninteresting line.  Here,
 297         * "interesting" does not mean interesting(), but marked by
 298         * the give_context() function below (i.e. it includes context
 299         * lines that are not interesting to interesting() function
 300         * that are surrounded by interesting() ones.
 301         */
 302        while (i <= cnt)
 303                if (look_for_uninteresting
 304                    ? !(sline[i].flag & mark)
 305                    : (sline[i].flag & mark))
 306                        return i;
 307                else
 308                        i++;
 309        return i;
 310}
 311
 312static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
 313{
 314        unsigned long all_mask = (1UL<<num_parent) - 1;
 315        unsigned long mark = (1UL<<num_parent);
 316        unsigned long no_pre_delete = (2UL<<num_parent);
 317        unsigned long i;
 318
 319        /* Two groups of interesting lines may have a short gap of
 320         * uninteresting lines.  Connect such groups to give them a
 321         * bit of context.
 322         *
 323         * We first start from what the interesting() function says,
 324         * and mark them with "mark", and paint context lines with the
 325         * mark.  So interesting() would still say false for such context
 326         * lines but they are treated as "interesting" in the end.
 327         */
 328        i = find_next(sline, mark, 0, cnt, 0);
 329        if (cnt < i)
 330                return 0;
 331
 332        while (i <= cnt) {
 333                unsigned long j = (context < i) ? (i - context) : 0;
 334                unsigned long k;
 335
 336                /* Paint a few lines before the first interesting line. */
 337                while (j < i)
 338                        sline[j++].flag |= mark | no_pre_delete;
 339
 340        again:
 341                /* we know up to i is to be included.  where does the
 342                 * next uninteresting one start?
 343                 */
 344                j = find_next(sline, mark, i, cnt, 1);
 345                if (cnt < j)
 346                        break; /* the rest are all interesting */
 347
 348                /* lookahead context lines */
 349                k = find_next(sline, mark, j, cnt, 0);
 350                j = adjust_hunk_tail(sline, all_mask, i, j);
 351
 352                if (k < j + context) {
 353                        /* k is interesting and [j,k) are not, but
 354                         * paint them interesting because the gap is small.
 355                         */
 356                        while (j < k)
 357                                sline[j++].flag |= mark;
 358                        i = k;
 359                        goto again;
 360                }
 361
 362                /* j is the first uninteresting line and there is
 363                 * no overlap beyond it within context lines.  Paint
 364                 * the trailing edge a bit.
 365                 */
 366                i = k;
 367                k = (j + context < cnt+1) ? j + context : cnt+1;
 368                while (j < k)
 369                        sline[j++].flag |= mark;
 370        }
 371        return 1;
 372}
 373
 374static int make_hunks(struct sline *sline, unsigned long cnt,
 375                       int num_parent, int dense)
 376{
 377        unsigned long all_mask = (1UL<<num_parent) - 1;
 378        unsigned long mark = (1UL<<num_parent);
 379        unsigned long i;
 380        int has_interesting = 0;
 381
 382        for (i = 0; i <= cnt; i++) {
 383                if (interesting(&sline[i], all_mask))
 384                        sline[i].flag |= mark;
 385                else
 386                        sline[i].flag &= ~mark;
 387        }
 388        if (!dense)
 389                return give_context(sline, cnt, num_parent);
 390
 391        /* Look at each hunk, and if we have changes from only one
 392         * parent, or the changes are the same from all but one
 393         * parent, mark that uninteresting.
 394         */
 395        i = 0;
 396        while (i <= cnt) {
 397                unsigned long j, hunk_begin, hunk_end;
 398                unsigned long same_diff;
 399                while (i <= cnt && !(sline[i].flag & mark))
 400                        i++;
 401                if (cnt < i)
 402                        break; /* No more interesting hunks */
 403                hunk_begin = i;
 404                for (j = i + 1; j <= cnt; j++) {
 405                        if (!(sline[j].flag & mark)) {
 406                                /* Look beyond the end to see if there
 407                                 * is an interesting line after this
 408                                 * hunk within context span.
 409                                 */
 410                                unsigned long la; /* lookahead */
 411                                int contin = 0;
 412                                la = adjust_hunk_tail(sline, all_mask,
 413                                                     hunk_begin, j);
 414                                la = (la + context < cnt + 1) ?
 415                                        (la + context) : cnt + 1;
 416                                while (j <= --la) {
 417                                        if (sline[la].flag & mark) {
 418                                                contin = 1;
 419                                                break;
 420                                        }
 421                                }
 422                                if (!contin)
 423                                        break;
 424                                j = la;
 425                        }
 426                }
 427                hunk_end = j;
 428
 429                /* [i..hunk_end) are interesting.  Now is it really
 430                 * interesting?  We check if there are only two versions
 431                 * and the result matches one of them.  That is, we look
 432                 * at:
 433                 *   (+) line, which records lines added to which parents;
 434                 *       this line appears in the result.
 435                 *   (-) line, which records from what parents the line
 436                 *       was removed; this line does not appear in the result.
 437                 * then check the set of parents the result has difference
 438                 * from, from all lines.  If there are lines that has
 439                 * different set of parents that the result has differences
 440                 * from, that means we have more than two versions.
 441                 *
 442                 * Even when we have only two versions, if the result does
 443                 * not match any of the parents, the it should be considered
 444                 * interesting.  In such a case, we would have all '+' line.
 445                 * After passing the above "two versions" test, that would
 446                 * appear as "the same set of parents" to be "all parents".
 447                 */
 448                same_diff = 0;
 449                has_interesting = 0;
 450                for (j = i; j < hunk_end && !has_interesting; j++) {
 451                        unsigned long this_diff = sline[j].flag & all_mask;
 452                        struct lline *ll = sline[j].lost_head;
 453                        if (this_diff) {
 454                                /* This has some changes.  Is it the
 455                                 * same as others?
 456                                 */
 457                                if (!same_diff)
 458                                        same_diff = this_diff;
 459                                else if (same_diff != this_diff) {
 460                                        has_interesting = 1;
 461                                        break;
 462                                }
 463                        }
 464                        while (ll && !has_interesting) {
 465                                /* Lost this line from these parents;
 466                                 * who are they?  Are they the same?
 467                                 */
 468                                this_diff = ll->parent_map;
 469                                if (!same_diff)
 470                                        same_diff = this_diff;
 471                                else if (same_diff != this_diff) {
 472                                        has_interesting = 1;
 473                                }
 474                                ll = ll->next;
 475                        }
 476                }
 477
 478                if (!has_interesting && same_diff != all_mask) {
 479                        /* This hunk is not that interesting after all */
 480                        for (j = hunk_begin; j < hunk_end; j++)
 481                                sline[j].flag &= ~mark;
 482                }
 483                i = hunk_end;
 484        }
 485
 486        has_interesting = give_context(sline, cnt, num_parent);
 487        return has_interesting;
 488}
 489
 490static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, int n, unsigned long null_context)
 491{
 492        l0 = sline[l0].p_lno[n];
 493        l1 = sline[l1].p_lno[n];
 494        printf(" -%lu,%lu", l0, l1-l0-null_context);
 495}
 496
 497static int hunk_comment_line(const char *bol)
 498{
 499        int ch;
 500
 501        if (!bol)
 502                return 0;
 503        ch = *bol & 0xff;
 504        return (isalpha(ch) || ch == '_' || ch == '$');
 505}
 506
 507static void show_line_to_eol(const char *line, int len, const char *reset)
 508{
 509        int saw_cr_at_eol = 0;
 510        if (len < 0)
 511                len = strlen(line);
 512        saw_cr_at_eol = (len && line[len-1] == '\r');
 513
 514        printf("%.*s%s%s\n", len - saw_cr_at_eol, line,
 515               reset,
 516               saw_cr_at_eol ? "\r" : "");
 517}
 518
 519static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
 520                       int use_color, int result_deleted)
 521{
 522        unsigned long mark = (1UL<<num_parent);
 523        unsigned long no_pre_delete = (2UL<<num_parent);
 524        int i;
 525        unsigned long lno = 0;
 526        const char *c_frag = diff_get_color(use_color, DIFF_FRAGINFO);
 527        const char *c_func = diff_get_color(use_color, DIFF_FUNCINFO);
 528        const char *c_new = diff_get_color(use_color, DIFF_FILE_NEW);
 529        const char *c_old = diff_get_color(use_color, DIFF_FILE_OLD);
 530        const char *c_plain = diff_get_color(use_color, DIFF_PLAIN);
 531        const char *c_reset = diff_get_color(use_color, DIFF_RESET);
 532
 533        if (result_deleted)
 534                return; /* result deleted */
 535
 536        while (1) {
 537                unsigned long hunk_end;
 538                unsigned long rlines;
 539                const char *hunk_comment = NULL;
 540                unsigned long null_context = 0;
 541
 542                while (lno <= cnt && !(sline[lno].flag & mark)) {
 543                        if (hunk_comment_line(sline[lno].bol))
 544                                hunk_comment = sline[lno].bol;
 545                        lno++;
 546                }
 547                if (cnt < lno)
 548                        break;
 549                else {
 550                        for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
 551                                if (!(sline[hunk_end].flag & mark))
 552                                        break;
 553                }
 554                rlines = hunk_end - lno;
 555                if (cnt < hunk_end)
 556                        rlines--; /* pointing at the last delete hunk */
 557
 558                if (!context) {
 559                        /*
 560                         * Even when running with --unified=0, all
 561                         * lines in the hunk needs to be processed in
 562                         * the loop below in order to show the
 563                         * deletion recorded in lost_head.  However,
 564                         * we do not want to show the resulting line
 565                         * with all blank context markers in such a
 566                         * case.  Compensate.
 567                         */
 568                        unsigned long j;
 569                        for (j = lno; j < hunk_end; j++)
 570                                if (!(sline[j].flag & (mark-1)))
 571                                        null_context++;
 572                        rlines -= null_context;
 573                }
 574
 575                fputs(c_frag, stdout);
 576                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 577                for (i = 0; i < num_parent; i++)
 578                        show_parent_lno(sline, lno, hunk_end, i, null_context);
 579                printf(" +%lu,%lu ", lno+1, rlines);
 580                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 581
 582                if (hunk_comment) {
 583                        int comment_end = 0;
 584                        for (i = 0; i < 40; i++) {
 585                                int ch = hunk_comment[i] & 0xff;
 586                                if (!ch || ch == '\n')
 587                                        break;
 588                                if (!isspace(ch))
 589                                    comment_end = i;
 590                        }
 591                        if (comment_end)
 592                                printf("%s%s %s%s", c_reset,
 593                                                    c_plain, c_reset,
 594                                                    c_func);
 595                        for (i = 0; i < comment_end; i++)
 596                                putchar(hunk_comment[i]);
 597                }
 598
 599                printf("%s\n", c_reset);
 600                while (lno < hunk_end) {
 601                        struct lline *ll;
 602                        int j;
 603                        unsigned long p_mask;
 604                        struct sline *sl = &sline[lno++];
 605                        ll = (sl->flag & no_pre_delete) ? NULL : sl->lost_head;
 606                        while (ll) {
 607                                fputs(c_old, stdout);
 608                                for (j = 0; j < num_parent; j++) {
 609                                        if (ll->parent_map & (1UL<<j))
 610                                                putchar('-');
 611                                        else
 612                                                putchar(' ');
 613                                }
 614                                show_line_to_eol(ll->line, -1, c_reset);
 615                                ll = ll->next;
 616                        }
 617                        if (cnt < lno)
 618                                break;
 619                        p_mask = 1;
 620                        if (!(sl->flag & (mark-1))) {
 621                                /*
 622                                 * This sline was here to hang the
 623                                 * lost lines in front of it.
 624                                 */
 625                                if (!context)
 626                                        continue;
 627                                fputs(c_plain, stdout);
 628                        }
 629                        else
 630                                fputs(c_new, stdout);
 631                        for (j = 0; j < num_parent; j++) {
 632                                if (p_mask & sl->flag)
 633                                        putchar('+');
 634                                else
 635                                        putchar(' ');
 636                                p_mask <<= 1;
 637                        }
 638                        show_line_to_eol(sl->bol, sl->len, c_reset);
 639                }
 640        }
 641}
 642
 643static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
 644                               int i, int j)
 645{
 646        /* We have already examined parent j and we know parent i
 647         * and parent j are the same, so reuse the combined result
 648         * of parent j for parent i.
 649         */
 650        unsigned long lno, imask, jmask;
 651        imask = (1UL<<i);
 652        jmask = (1UL<<j);
 653
 654        for (lno = 0; lno <= cnt; lno++) {
 655                struct lline *ll = sline->lost_head;
 656                sline->p_lno[i] = sline->p_lno[j];
 657                while (ll) {
 658                        if (ll->parent_map & jmask)
 659                                ll->parent_map |= imask;
 660                        ll = ll->next;
 661                }
 662                if (sline->flag & jmask)
 663                        sline->flag |= imask;
 664                sline++;
 665        }
 666        /* the overall size of the file (sline[cnt]) */
 667        sline->p_lno[i] = sline->p_lno[j];
 668}
 669
 670static void dump_quoted_path(const char *head,
 671                             const char *prefix,
 672                             const char *path,
 673                             const char *c_meta, const char *c_reset)
 674{
 675        static struct strbuf buf = STRBUF_INIT;
 676
 677        strbuf_reset(&buf);
 678        strbuf_addstr(&buf, c_meta);
 679        strbuf_addstr(&buf, head);
 680        quote_two_c_style(&buf, prefix, path, 0);
 681        strbuf_addstr(&buf, c_reset);
 682        puts(buf.buf);
 683}
 684
 685static void show_combined_header(struct combine_diff_path *elem,
 686                                 int num_parent,
 687                                 int dense,
 688                                 struct rev_info *rev,
 689                                 int mode_differs,
 690                                 int show_file_header)
 691{
 692        struct diff_options *opt = &rev->diffopt;
 693        int abbrev = DIFF_OPT_TST(opt, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
 694        const char *a_prefix = opt->a_prefix ? opt->a_prefix : "a/";
 695        const char *b_prefix = opt->b_prefix ? opt->b_prefix : "b/";
 696        int use_color = DIFF_OPT_TST(opt, COLOR_DIFF);
 697        const char *c_meta = diff_get_color(use_color, DIFF_METAINFO);
 698        const char *c_reset = diff_get_color(use_color, DIFF_RESET);
 699        const char *abb;
 700        int added = 0;
 701        int deleted = 0;
 702        int i;
 703
 704        if (rev->loginfo && !rev->no_commit_id)
 705                show_log(rev);
 706
 707        dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
 708                         "", elem->path, c_meta, c_reset);
 709        printf("%sindex ", c_meta);
 710        for (i = 0; i < num_parent; i++) {
 711                abb = find_unique_abbrev(elem->parent[i].sha1,
 712                                         abbrev);
 713                printf("%s%s", i ? "," : "", abb);
 714        }
 715        abb = find_unique_abbrev(elem->sha1, abbrev);
 716        printf("..%s%s\n", abb, c_reset);
 717
 718        if (mode_differs) {
 719                deleted = !elem->mode;
 720
 721                /* We say it was added if nobody had it */
 722                added = !deleted;
 723                for (i = 0; added && i < num_parent; i++)
 724                        if (elem->parent[i].status !=
 725                            DIFF_STATUS_ADDED)
 726                                added = 0;
 727                if (added)
 728                        printf("%snew file mode %06o",
 729                               c_meta, elem->mode);
 730                else {
 731                        if (deleted)
 732                                printf("%sdeleted file ", c_meta);
 733                        printf("mode ");
 734                        for (i = 0; i < num_parent; i++) {
 735                                printf("%s%06o", i ? "," : "",
 736                                       elem->parent[i].mode);
 737                        }
 738                        if (elem->mode)
 739                                printf("..%06o", elem->mode);
 740                }
 741                printf("%s\n", c_reset);
 742        }
 743
 744        if (!show_file_header)
 745                return;
 746
 747        if (added)
 748                dump_quoted_path("--- ", "", "/dev/null",
 749                                 c_meta, c_reset);
 750        else
 751                dump_quoted_path("--- ", a_prefix, elem->path,
 752                                 c_meta, c_reset);
 753        if (deleted)
 754                dump_quoted_path("+++ ", "", "/dev/null",
 755                                 c_meta, c_reset);
 756        else
 757                dump_quoted_path("+++ ", b_prefix, elem->path,
 758                                 c_meta, c_reset);
 759}
 760
 761static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
 762                            int dense, struct rev_info *rev)
 763{
 764        struct diff_options *opt = &rev->diffopt;
 765        unsigned long result_size, cnt, lno;
 766        int result_deleted = 0;
 767        char *result, *cp;
 768        struct sline *sline; /* survived lines */
 769        int mode_differs = 0;
 770        int i, show_hunks;
 771        int working_tree_file = is_null_sha1(elem->sha1);
 772        mmfile_t result_file;
 773        struct userdiff_driver *userdiff;
 774        int is_binary;
 775
 776        context = opt->context;
 777        userdiff = userdiff_find_by_path(elem->path);
 778        if (!userdiff)
 779                userdiff = userdiff_find_by_name("default");
 780
 781        /* Read the result of merge first */
 782        if (!working_tree_file)
 783                result = grab_blob(elem->sha1, elem->mode, &result_size);
 784        else {
 785                /* Used by diff-tree to read from the working tree */
 786                struct stat st;
 787                int fd = -1;
 788
 789                if (lstat(elem->path, &st) < 0)
 790                        goto deleted_file;
 791
 792                if (S_ISLNK(st.st_mode)) {
 793                        struct strbuf buf = STRBUF_INIT;
 794
 795                        if (strbuf_readlink(&buf, elem->path, st.st_size) < 0) {
 796                                error("readlink(%s): %s", elem->path,
 797                                      strerror(errno));
 798                                return;
 799                        }
 800                        result_size = buf.len;
 801                        result = strbuf_detach(&buf, NULL);
 802                        elem->mode = canon_mode(st.st_mode);
 803                } else if (S_ISDIR(st.st_mode)) {
 804                        unsigned char sha1[20];
 805                        if (resolve_gitlink_ref(elem->path, "HEAD", sha1) < 0)
 806                                result = grab_blob(elem->sha1, elem->mode, &result_size);
 807                        else
 808                                result = grab_blob(sha1, elem->mode, &result_size);
 809                } else if (0 <= (fd = open(elem->path, O_RDONLY))) {
 810                        size_t len = xsize_t(st.st_size);
 811                        ssize_t done;
 812                        int is_file, i;
 813
 814                        elem->mode = canon_mode(st.st_mode);
 815                        /* if symlinks don't work, assume symlink if all parents
 816                         * are symlinks
 817                         */
 818                        is_file = has_symlinks;
 819                        for (i = 0; !is_file && i < num_parent; i++)
 820                                is_file = !S_ISLNK(elem->parent[i].mode);
 821                        if (!is_file)
 822                                elem->mode = canon_mode(S_IFLNK);
 823
 824                        result_size = len;
 825                        result = xmalloc(len + 1);
 826
 827                        done = read_in_full(fd, result, len);
 828                        if (done < 0)
 829                                die_errno("read error '%s'", elem->path);
 830                        else if (done < len)
 831                                die("early EOF '%s'", elem->path);
 832
 833                        result[len] = 0;
 834
 835                        /* If not a fake symlink, apply filters, e.g. autocrlf */
 836                        if (is_file) {
 837                                struct strbuf buf = STRBUF_INIT;
 838
 839                                if (convert_to_git(elem->path, result, len, &buf, safe_crlf)) {
 840                                        free(result);
 841                                        result = strbuf_detach(&buf, &len);
 842                                        result_size = len;
 843                                }
 844                        }
 845                }
 846                else {
 847                deleted_file:
 848                        result_deleted = 1;
 849                        result_size = 0;
 850                        elem->mode = 0;
 851                        result = xcalloc(1, 1);
 852                }
 853
 854                if (0 <= fd)
 855                        close(fd);
 856        }
 857
 858        for (i = 0; i < num_parent; i++) {
 859                if (elem->parent[i].mode != elem->mode) {
 860                        mode_differs = 1;
 861                        break;
 862                }
 863        }
 864
 865        if (userdiff->binary != -1)
 866                is_binary = userdiff->binary;
 867        else {
 868                is_binary = buffer_is_binary(result, result_size);
 869                for (i = 0; !is_binary && i < num_parent; i++) {
 870                        char *buf;
 871                        unsigned long size;
 872                        buf = grab_blob(elem->parent[i].sha1,
 873                                        elem->parent[i].mode,
 874                                        &size);
 875                        if (buffer_is_binary(buf, size))
 876                                is_binary = 1;
 877                        free(buf);
 878                }
 879        }
 880        if (is_binary) {
 881                show_combined_header(elem, num_parent, dense, rev,
 882                                     mode_differs, 0);
 883                printf("Binary files differ\n");
 884                free(result);
 885                return;
 886        }
 887
 888        for (cnt = 0, cp = result; cp < result + result_size; cp++) {
 889                if (*cp == '\n')
 890                        cnt++;
 891        }
 892        if (result_size && result[result_size-1] != '\n')
 893                cnt++; /* incomplete line */
 894
 895        sline = xcalloc(cnt+2, sizeof(*sline));
 896        sline[0].bol = result;
 897        for (lno = 0; lno <= cnt + 1; lno++) {
 898                sline[lno].lost_tail = &sline[lno].lost_head;
 899                sline[lno].flag = 0;
 900        }
 901        for (lno = 0, cp = result; cp < result + result_size; cp++) {
 902                if (*cp == '\n') {
 903                        sline[lno].len = cp - sline[lno].bol;
 904                        lno++;
 905                        if (lno < cnt)
 906                                sline[lno].bol = cp + 1;
 907                }
 908        }
 909        if (result_size && result[result_size-1] != '\n')
 910                sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
 911
 912        result_file.ptr = result;
 913        result_file.size = result_size;
 914
 915        /* Even p_lno[cnt+1] is valid -- that is for the end line number
 916         * for deletion hunk at the end.
 917         */
 918        sline[0].p_lno = xcalloc((cnt+2) * num_parent, sizeof(unsigned long));
 919        for (lno = 0; lno <= cnt; lno++)
 920                sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
 921
 922        for (i = 0; i < num_parent; i++) {
 923                int j;
 924                for (j = 0; j < i; j++) {
 925                        if (!hashcmp(elem->parent[i].sha1,
 926                                     elem->parent[j].sha1)) {
 927                                reuse_combine_diff(sline, cnt, i, j);
 928                                break;
 929                        }
 930                }
 931                if (i <= j)
 932                        combine_diff(elem->parent[i].sha1,
 933                                     elem->parent[i].mode,
 934                                     &result_file, sline,
 935                                     cnt, i, num_parent, result_deleted);
 936        }
 937
 938        show_hunks = make_hunks(sline, cnt, num_parent, dense);
 939
 940        if (show_hunks || mode_differs || working_tree_file) {
 941                show_combined_header(elem, num_parent, dense, rev,
 942                                     mode_differs, 1);
 943                dump_sline(sline, cnt, num_parent,
 944                           DIFF_OPT_TST(opt, COLOR_DIFF), result_deleted);
 945        }
 946        free(result);
 947
 948        for (lno = 0; lno < cnt; lno++) {
 949                if (sline[lno].lost_head) {
 950                        struct lline *ll = sline[lno].lost_head;
 951                        while (ll) {
 952                                struct lline *tmp = ll;
 953                                ll = ll->next;
 954                                free(tmp);
 955                        }
 956                }
 957        }
 958        free(sline[0].p_lno);
 959        free(sline);
 960}
 961
 962#define COLONS "::::::::::::::::::::::::::::::::"
 963
 964static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct rev_info *rev)
 965{
 966        struct diff_options *opt = &rev->diffopt;
 967        int i, offset;
 968        const char *prefix;
 969        int line_termination, inter_name_termination;
 970
 971        line_termination = opt->line_termination;
 972        inter_name_termination = '\t';
 973        if (!line_termination)
 974                inter_name_termination = 0;
 975
 976        if (rev->loginfo && !rev->no_commit_id)
 977                show_log(rev);
 978
 979        if (opt->output_format & DIFF_FORMAT_RAW) {
 980                offset = strlen(COLONS) - num_parent;
 981                if (offset < 0)
 982                        offset = 0;
 983                prefix = COLONS + offset;
 984
 985                /* Show the modes */
 986                for (i = 0; i < num_parent; i++) {
 987                        printf("%s%06o", prefix, p->parent[i].mode);
 988                        prefix = " ";
 989                }
 990                printf("%s%06o", prefix, p->mode);
 991
 992                /* Show sha1's */
 993                for (i = 0; i < num_parent; i++)
 994                        printf(" %s", diff_unique_abbrev(p->parent[i].sha1,
 995                                                         opt->abbrev));
 996                printf(" %s ", diff_unique_abbrev(p->sha1, opt->abbrev));
 997        }
 998
 999        if (opt->output_format & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS)) {
1000                for (i = 0; i < num_parent; i++)
1001                        putchar(p->parent[i].status);
1002                putchar(inter_name_termination);
1003        }
1004
1005        write_name_quoted(p->path, stdout, line_termination);
1006}
1007
1008void show_combined_diff(struct combine_diff_path *p,
1009                       int num_parent,
1010                       int dense,
1011                       struct rev_info *rev)
1012{
1013        struct diff_options *opt = &rev->diffopt;
1014        if (!p->len)
1015                return;
1016        if (opt->output_format & (DIFF_FORMAT_RAW |
1017                                  DIFF_FORMAT_NAME |
1018                                  DIFF_FORMAT_NAME_STATUS))
1019                show_raw_diff(p, num_parent, rev);
1020        else if (opt->output_format & DIFF_FORMAT_PATCH)
1021                show_patch_diff(p, num_parent, dense, rev);
1022}
1023
1024void diff_tree_combined(const unsigned char *sha1,
1025                        const unsigned char parent[][20],
1026                        int num_parent,
1027                        int dense,
1028                        struct rev_info *rev)
1029{
1030        struct diff_options *opt = &rev->diffopt;
1031        struct diff_options diffopts;
1032        struct combine_diff_path *p, *paths = NULL;
1033        int i, num_paths, needsep, show_log_first;
1034
1035        diffopts = *opt;
1036        diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
1037        DIFF_OPT_SET(&diffopts, RECURSIVE);
1038        DIFF_OPT_CLR(&diffopts, ALLOW_EXTERNAL);
1039
1040        show_log_first = !!rev->loginfo && !rev->no_commit_id;
1041        needsep = 0;
1042        /* find set of paths that everybody touches */
1043        for (i = 0; i < num_parent; i++) {
1044                /* show stat against the first parent even
1045                 * when doing combined diff.
1046                 */
1047                int stat_opt = (opt->output_format &
1048                                (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
1049                if (i == 0 && stat_opt)
1050                        diffopts.output_format = stat_opt;
1051                else
1052                        diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
1053                diff_tree_sha1(parent[i], sha1, "", &diffopts);
1054                diffcore_std(&diffopts);
1055                paths = intersect_paths(paths, i, num_parent);
1056
1057                if (show_log_first && i == 0) {
1058                        show_log(rev);
1059                        if (rev->verbose_header && opt->output_format)
1060                                putchar(opt->line_termination);
1061                }
1062                diff_flush(&diffopts);
1063        }
1064
1065        /* find out surviving paths */
1066        for (num_paths = 0, p = paths; p; p = p->next) {
1067                if (p->len)
1068                        num_paths++;
1069        }
1070        if (num_paths) {
1071                if (opt->output_format & (DIFF_FORMAT_RAW |
1072                                          DIFF_FORMAT_NAME |
1073                                          DIFF_FORMAT_NAME_STATUS)) {
1074                        for (p = paths; p; p = p->next) {
1075                                if (p->len)
1076                                        show_raw_diff(p, num_parent, rev);
1077                        }
1078                        needsep = 1;
1079                }
1080                else if (opt->output_format &
1081                         (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT))
1082                        needsep = 1;
1083                if (opt->output_format & DIFF_FORMAT_PATCH) {
1084                        if (needsep)
1085                                putchar(opt->line_termination);
1086                        for (p = paths; p; p = p->next) {
1087                                if (p->len)
1088                                        show_patch_diff(p, num_parent, dense,
1089                                                        rev);
1090                        }
1091                }
1092        }
1093
1094        /* Clean things up */
1095        while (paths) {
1096                struct combine_diff_path *tmp = paths;
1097                paths = paths->next;
1098                free(tmp);
1099        }
1100}
1101
1102void diff_tree_combined_merge(const unsigned char *sha1,
1103                             int dense, struct rev_info *rev)
1104{
1105        int num_parent;
1106        const unsigned char (*parent)[20];
1107        struct commit *commit = lookup_commit(sha1);
1108        struct commit_list *parents;
1109
1110        /* count parents */
1111        for (parents = commit->parents, num_parent = 0;
1112             parents;
1113             parents = parents->next, num_parent++)
1114                ; /* nothing */
1115
1116        parent = xmalloc(num_parent * sizeof(*parent));
1117        for (parents = commit->parents, num_parent = 0;
1118             parents;
1119             parents = parents->next, num_parent++)
1120                hashcpy((unsigned char *)(parent + num_parent),
1121                        parents->item->object.sha1);
1122        diff_tree_combined(sha1, parent, num_parent, dense, rev);
1123}