combine-diff.con commit Merge branch 'ma/mailing-list-address-in-git-help' (20f28d7)
   1#include "cache.h"
   2#include "object-store.h"
   3#include "commit.h"
   4#include "blob.h"
   5#include "diff.h"
   6#include "diffcore.h"
   7#include "quote.h"
   8#include "xdiff-interface.h"
   9#include "xdiff/xmacros.h"
  10#include "log-tree.h"
  11#include "refs.h"
  12#include "userdiff.h"
  13#include "sha1-array.h"
  14#include "revision.h"
  15
  16static int compare_paths(const struct combine_diff_path *one,
  17                          const struct diff_filespec *two)
  18{
  19        if (!S_ISDIR(one->mode) && !S_ISDIR(two->mode))
  20                return strcmp(one->path, two->path);
  21
  22        return base_name_compare(one->path, strlen(one->path), one->mode,
  23                                 two->path, strlen(two->path), two->mode);
  24}
  25
  26static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
  27{
  28        struct diff_queue_struct *q = &diff_queued_diff;
  29        struct combine_diff_path *p, **tail = &curr;
  30        int i, cmp;
  31
  32        if (!n) {
  33                for (i = 0; i < q->nr; i++) {
  34                        int len;
  35                        const char *path;
  36                        if (diff_unmodified_pair(q->queue[i]))
  37                                continue;
  38                        path = q->queue[i]->two->path;
  39                        len = strlen(path);
  40                        p = xmalloc(combine_diff_path_size(num_parent, len));
  41                        p->path = (char *) &(p->parent[num_parent]);
  42                        memcpy(p->path, path, len);
  43                        p->path[len] = 0;
  44                        p->next = NULL;
  45                        memset(p->parent, 0,
  46                               sizeof(p->parent[0]) * num_parent);
  47
  48                        oidcpy(&p->oid, &q->queue[i]->two->oid);
  49                        p->mode = q->queue[i]->two->mode;
  50                        oidcpy(&p->parent[n].oid, &q->queue[i]->one->oid);
  51                        p->parent[n].mode = q->queue[i]->one->mode;
  52                        p->parent[n].status = q->queue[i]->status;
  53                        *tail = p;
  54                        tail = &p->next;
  55                }
  56                return curr;
  57        }
  58
  59        /*
  60         * paths in curr (linked list) and q->queue[] (array) are
  61         * both sorted in the tree order.
  62         */
  63        i = 0;
  64        while ((p = *tail) != NULL) {
  65                cmp = ((i >= q->nr)
  66                       ? -1 : compare_paths(p, q->queue[i]->two));
  67
  68                if (cmp < 0) {
  69                        /* p->path not in q->queue[]; drop it */
  70                        *tail = p->next;
  71                        free(p);
  72                        continue;
  73                }
  74
  75                if (cmp > 0) {
  76                        /* q->queue[i] not in p->path; skip it */
  77                        i++;
  78                        continue;
  79                }
  80
  81                oidcpy(&p->parent[n].oid, &q->queue[i]->one->oid);
  82                p->parent[n].mode = q->queue[i]->one->mode;
  83                p->parent[n].status = q->queue[i]->status;
  84
  85                tail = &p->next;
  86                i++;
  87        }
  88        return curr;
  89}
  90
  91/* Lines lost from parent */
  92struct lline {
  93        struct lline *next, *prev;
  94        int len;
  95        unsigned long parent_map;
  96        char line[FLEX_ARRAY];
  97};
  98
  99/* Lines lost from current parent (before coalescing) */
 100struct plost {
 101        struct lline *lost_head, *lost_tail;
 102        int len;
 103};
 104
 105/* Lines surviving in the merge result */
 106struct sline {
 107        /* Accumulated and coalesced lost lines */
 108        struct lline *lost;
 109        int lenlost;
 110        struct plost plost;
 111        char *bol;
 112        int len;
 113        /* bit 0 up to (N-1) are on if the parent has this line (i.e.
 114         * we did not change it).
 115         * bit N is used for "interesting" lines, including context.
 116         * bit (N+1) is used for "do not show deletion before this".
 117         */
 118        unsigned long flag;
 119        unsigned long *p_lno;
 120};
 121
 122static int match_string_spaces(const char *line1, int len1,
 123                               const char *line2, int len2,
 124                               long flags)
 125{
 126        if (flags & XDF_WHITESPACE_FLAGS) {
 127                for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
 128                for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
 129        }
 130
 131        if (!(flags & (XDF_IGNORE_WHITESPACE | XDF_IGNORE_WHITESPACE_CHANGE)))
 132                return (len1 == len2 && !memcmp(line1, line2, len1));
 133
 134        while (len1 > 0 && len2 > 0) {
 135                len1--;
 136                len2--;
 137                if (XDL_ISSPACE(line1[len1]) || XDL_ISSPACE(line2[len2])) {
 138                        if ((flags & XDF_IGNORE_WHITESPACE_CHANGE) &&
 139                            (!XDL_ISSPACE(line1[len1]) || !XDL_ISSPACE(line2[len2])))
 140                                return 0;
 141
 142                        for (; len1 > 0 && XDL_ISSPACE(line1[len1]); len1--);
 143                        for (; len2 > 0 && XDL_ISSPACE(line2[len2]); len2--);
 144                }
 145                if (line1[len1] != line2[len2])
 146                        return 0;
 147        }
 148
 149        if (flags & XDF_IGNORE_WHITESPACE) {
 150                /* Consume remaining spaces */
 151                for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
 152                for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
 153        }
 154
 155        /* We matched full line1 and line2 */
 156        if (!len1 && !len2)
 157                return 1;
 158
 159        return 0;
 160}
 161
 162enum coalesce_direction { MATCH, BASE, NEW };
 163
 164/* Coalesce new lines into base by finding LCS */
 165static struct lline *coalesce_lines(struct lline *base, int *lenbase,
 166                                    struct lline *newline, int lennew,
 167                                    unsigned long parent, long flags)
 168{
 169        int **lcs;
 170        enum coalesce_direction **directions;
 171        struct lline *baseend, *newend = NULL;
 172        int i, j, origbaselen = *lenbase;
 173
 174        if (newline == NULL)
 175                return base;
 176
 177        if (base == NULL) {
 178                *lenbase = lennew;
 179                return newline;
 180        }
 181
 182        /*
 183         * Coalesce new lines into base by finding the LCS
 184         * - Create the table to run dynamic programming
 185         * - Compute the LCS
 186         * - Then reverse read the direction structure:
 187         *   - If we have MATCH, assign parent to base flag, and consume
 188         *   both baseend and newend
 189         *   - Else if we have BASE, consume baseend
 190         *   - Else if we have NEW, insert newend lline into base and
 191         *   consume newend
 192         */
 193        lcs = xcalloc(st_add(origbaselen, 1), sizeof(int*));
 194        directions = xcalloc(st_add(origbaselen, 1), sizeof(enum coalesce_direction*));
 195        for (i = 0; i < origbaselen + 1; i++) {
 196                lcs[i] = xcalloc(st_add(lennew, 1), sizeof(int));
 197                directions[i] = xcalloc(st_add(lennew, 1), sizeof(enum coalesce_direction));
 198                directions[i][0] = BASE;
 199        }
 200        for (j = 1; j < lennew + 1; j++)
 201                directions[0][j] = NEW;
 202
 203        for (i = 1, baseend = base; i < origbaselen + 1; i++) {
 204                for (j = 1, newend = newline; j < lennew + 1; j++) {
 205                        if (match_string_spaces(baseend->line, baseend->len,
 206                                                newend->line, newend->len, flags)) {
 207                                lcs[i][j] = lcs[i - 1][j - 1] + 1;
 208                                directions[i][j] = MATCH;
 209                        } else if (lcs[i][j - 1] >= lcs[i - 1][j]) {
 210                                lcs[i][j] = lcs[i][j - 1];
 211                                directions[i][j] = NEW;
 212                        } else {
 213                                lcs[i][j] = lcs[i - 1][j];
 214                                directions[i][j] = BASE;
 215                        }
 216                        if (newend->next)
 217                                newend = newend->next;
 218                }
 219                if (baseend->next)
 220                        baseend = baseend->next;
 221        }
 222
 223        for (i = 0; i < origbaselen + 1; i++)
 224                free(lcs[i]);
 225        free(lcs);
 226
 227        /* At this point, baseend and newend point to the end of each lists */
 228        i--;
 229        j--;
 230        while (i != 0 || j != 0) {
 231                if (directions[i][j] == MATCH) {
 232                        baseend->parent_map |= 1<<parent;
 233                        baseend = baseend->prev;
 234                        newend = newend->prev;
 235                        i--;
 236                        j--;
 237                } else if (directions[i][j] == NEW) {
 238                        struct lline *lline;
 239
 240                        lline = newend;
 241                        /* Remove lline from new list and update newend */
 242                        if (lline->prev)
 243                                lline->prev->next = lline->next;
 244                        else
 245                                newline = lline->next;
 246                        if (lline->next)
 247                                lline->next->prev = lline->prev;
 248
 249                        newend = lline->prev;
 250                        j--;
 251
 252                        /* Add lline to base list */
 253                        if (baseend) {
 254                                lline->next = baseend->next;
 255                                lline->prev = baseend;
 256                                if (lline->prev)
 257                                        lline->prev->next = lline;
 258                        }
 259                        else {
 260                                lline->next = base;
 261                                base = lline;
 262                        }
 263                        (*lenbase)++;
 264
 265                        if (lline->next)
 266                                lline->next->prev = lline;
 267
 268                } else {
 269                        baseend = baseend->prev;
 270                        i--;
 271                }
 272        }
 273
 274        newend = newline;
 275        while (newend) {
 276                struct lline *lline = newend;
 277                newend = newend->next;
 278                free(lline);
 279        }
 280
 281        for (i = 0; i < origbaselen + 1; i++)
 282                free(directions[i]);
 283        free(directions);
 284
 285        return base;
 286}
 287
 288static char *grab_blob(const struct object_id *oid, unsigned int mode,
 289                       unsigned long *size, struct userdiff_driver *textconv,
 290                       const char *path)
 291{
 292        char *blob;
 293        enum object_type type;
 294
 295        if (S_ISGITLINK(mode)) {
 296                struct strbuf buf = STRBUF_INIT;
 297                strbuf_addf(&buf, "Subproject commit %s\n", oid_to_hex(oid));
 298                *size = buf.len;
 299                blob = strbuf_detach(&buf, NULL);
 300        } else if (is_null_oid(oid)) {
 301                /* deleted blob */
 302                *size = 0;
 303                return xcalloc(1, 1);
 304        } else if (textconv) {
 305                struct diff_filespec *df = alloc_filespec(path);
 306                fill_filespec(df, oid, 1, mode);
 307                *size = fill_textconv(textconv, df, &blob);
 308                free_filespec(df);
 309        } else {
 310                blob = read_object_file(oid, &type, size);
 311                if (type != OBJ_BLOB)
 312                        die("object '%s' is not a blob!", oid_to_hex(oid));
 313        }
 314        return blob;
 315}
 316
 317static void append_lost(struct sline *sline, int n, const char *line, int len)
 318{
 319        struct lline *lline;
 320        unsigned long this_mask = (1UL<<n);
 321        if (line[len-1] == '\n')
 322                len--;
 323
 324        FLEX_ALLOC_MEM(lline, line, line, len);
 325        lline->len = len;
 326        lline->next = NULL;
 327        lline->prev = sline->plost.lost_tail;
 328        if (lline->prev)
 329                lline->prev->next = lline;
 330        else
 331                sline->plost.lost_head = lline;
 332        sline->plost.lost_tail = lline;
 333        sline->plost.len++;
 334        lline->parent_map = this_mask;
 335}
 336
 337struct combine_diff_state {
 338        unsigned int lno;
 339        int ob, on, nb, nn;
 340        unsigned long nmask;
 341        int num_parent;
 342        int n;
 343        struct sline *sline;
 344        struct sline *lost_bucket;
 345};
 346
 347static void consume_line(void *state_, char *line, unsigned long len)
 348{
 349        struct combine_diff_state *state = state_;
 350        if (5 < len && !memcmp("@@ -", line, 4)) {
 351                if (parse_hunk_header(line, len,
 352                                      &state->ob, &state->on,
 353                                      &state->nb, &state->nn))
 354                        return;
 355                state->lno = state->nb;
 356                if (state->nn == 0) {
 357                        /* @@ -X,Y +N,0 @@ removed Y lines
 358                         * that would have come *after* line N
 359                         * in the result.  Our lost buckets hang
 360                         * to the line after the removed lines,
 361                         *
 362                         * Note that this is correct even when N == 0,
 363                         * in which case the hunk removes the first
 364                         * line in the file.
 365                         */
 366                        state->lost_bucket = &state->sline[state->nb];
 367                        if (!state->nb)
 368                                state->nb = 1;
 369                } else {
 370                        state->lost_bucket = &state->sline[state->nb-1];
 371                }
 372                if (!state->sline[state->nb-1].p_lno)
 373                        state->sline[state->nb-1].p_lno =
 374                                xcalloc(state->num_parent,
 375                                        sizeof(unsigned long));
 376                state->sline[state->nb-1].p_lno[state->n] = state->ob;
 377                return;
 378        }
 379        if (!state->lost_bucket)
 380                return; /* not in any hunk yet */
 381        switch (line[0]) {
 382        case '-':
 383                append_lost(state->lost_bucket, state->n, line+1, len-1);
 384                break;
 385        case '+':
 386                state->sline[state->lno-1].flag |= state->nmask;
 387                state->lno++;
 388                break;
 389        }
 390}
 391
 392static void combine_diff(const struct object_id *parent, unsigned int mode,
 393                         mmfile_t *result_file,
 394                         struct sline *sline, unsigned int cnt, int n,
 395                         int num_parent, int result_deleted,
 396                         struct userdiff_driver *textconv,
 397                         const char *path, long flags)
 398{
 399        unsigned int p_lno, lno;
 400        unsigned long nmask = (1UL << n);
 401        xpparam_t xpp;
 402        xdemitconf_t xecfg;
 403        mmfile_t parent_file;
 404        struct combine_diff_state state;
 405        unsigned long sz;
 406
 407        if (result_deleted)
 408                return; /* result deleted */
 409
 410        parent_file.ptr = grab_blob(parent, mode, &sz, textconv, path);
 411        parent_file.size = sz;
 412        memset(&xpp, 0, sizeof(xpp));
 413        xpp.flags = flags;
 414        memset(&xecfg, 0, sizeof(xecfg));
 415        memset(&state, 0, sizeof(state));
 416        state.nmask = nmask;
 417        state.sline = sline;
 418        state.lno = 1;
 419        state.num_parent = num_parent;
 420        state.n = n;
 421
 422        if (xdi_diff_outf(&parent_file, result_file, consume_line, &state,
 423                          &xpp, &xecfg))
 424                die("unable to generate combined diff for %s",
 425                    oid_to_hex(parent));
 426        free(parent_file.ptr);
 427
 428        /* Assign line numbers for this parent.
 429         *
 430         * sline[lno].p_lno[n] records the first line number
 431         * (counting from 1) for parent N if the final hunk display
 432         * started by showing sline[lno] (possibly showing the lost
 433         * lines attached to it first).
 434         */
 435        for (lno = 0,  p_lno = 1; lno <= cnt; lno++) {
 436                struct lline *ll;
 437                sline[lno].p_lno[n] = p_lno;
 438
 439                /* Coalesce new lines */
 440                if (sline[lno].plost.lost_head) {
 441                        struct sline *sl = &sline[lno];
 442                        sl->lost = coalesce_lines(sl->lost, &sl->lenlost,
 443                                                  sl->plost.lost_head,
 444                                                  sl->plost.len, n, flags);
 445                        sl->plost.lost_head = sl->plost.lost_tail = NULL;
 446                        sl->plost.len = 0;
 447                }
 448
 449                /* How many lines would this sline advance the p_lno? */
 450                ll = sline[lno].lost;
 451                while (ll) {
 452                        if (ll->parent_map & nmask)
 453                                p_lno++; /* '-' means parent had it */
 454                        ll = ll->next;
 455                }
 456                if (lno < cnt && !(sline[lno].flag & nmask))
 457                        p_lno++; /* no '+' means parent had it */
 458        }
 459        sline[lno].p_lno[n] = p_lno; /* trailer */
 460}
 461
 462static unsigned long context = 3;
 463static char combine_marker = '@';
 464
 465static int interesting(struct sline *sline, unsigned long all_mask)
 466{
 467        /* If some parents lost lines here, or if we have added to
 468         * some parent, it is interesting.
 469         */
 470        return ((sline->flag & all_mask) || sline->lost);
 471}
 472
 473static unsigned long adjust_hunk_tail(struct sline *sline,
 474                                      unsigned long all_mask,
 475                                      unsigned long hunk_begin,
 476                                      unsigned long i)
 477{
 478        /* i points at the first uninteresting line.  If the last line
 479         * of the hunk was interesting only because it has some
 480         * deletion, then it is not all that interesting for the
 481         * purpose of giving trailing context lines.  This is because
 482         * we output '-' line and then unmodified sline[i-1] itself in
 483         * that case which gives us one extra context line.
 484         */
 485        if ((hunk_begin + 1 <= i) && !(sline[i-1].flag & all_mask))
 486                i--;
 487        return i;
 488}
 489
 490static unsigned long find_next(struct sline *sline,
 491                               unsigned long mark,
 492                               unsigned long i,
 493                               unsigned long cnt,
 494                               int look_for_uninteresting)
 495{
 496        /* We have examined up to i-1 and are about to look at i.
 497         * Find next interesting or uninteresting line.  Here,
 498         * "interesting" does not mean interesting(), but marked by
 499         * the give_context() function below (i.e. it includes context
 500         * lines that are not interesting to interesting() function
 501         * that are surrounded by interesting() ones.
 502         */
 503        while (i <= cnt)
 504                if (look_for_uninteresting
 505                    ? !(sline[i].flag & mark)
 506                    : (sline[i].flag & mark))
 507                        return i;
 508                else
 509                        i++;
 510        return i;
 511}
 512
 513static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
 514{
 515        unsigned long all_mask = (1UL<<num_parent) - 1;
 516        unsigned long mark = (1UL<<num_parent);
 517        unsigned long no_pre_delete = (2UL<<num_parent);
 518        unsigned long i;
 519
 520        /* Two groups of interesting lines may have a short gap of
 521         * uninteresting lines.  Connect such groups to give them a
 522         * bit of context.
 523         *
 524         * We first start from what the interesting() function says,
 525         * and mark them with "mark", and paint context lines with the
 526         * mark.  So interesting() would still say false for such context
 527         * lines but they are treated as "interesting" in the end.
 528         */
 529        i = find_next(sline, mark, 0, cnt, 0);
 530        if (cnt < i)
 531                return 0;
 532
 533        while (i <= cnt) {
 534                unsigned long j = (context < i) ? (i - context) : 0;
 535                unsigned long k;
 536
 537                /* Paint a few lines before the first interesting line. */
 538                while (j < i) {
 539                        if (!(sline[j].flag & mark))
 540                                sline[j].flag |= no_pre_delete;
 541                        sline[j++].flag |= mark;
 542                }
 543
 544        again:
 545                /* we know up to i is to be included.  where does the
 546                 * next uninteresting one start?
 547                 */
 548                j = find_next(sline, mark, i, cnt, 1);
 549                if (cnt < j)
 550                        break; /* the rest are all interesting */
 551
 552                /* lookahead context lines */
 553                k = find_next(sline, mark, j, cnt, 0);
 554                j = adjust_hunk_tail(sline, all_mask, i, j);
 555
 556                if (k < j + context) {
 557                        /* k is interesting and [j,k) are not, but
 558                         * paint them interesting because the gap is small.
 559                         */
 560                        while (j < k)
 561                                sline[j++].flag |= mark;
 562                        i = k;
 563                        goto again;
 564                }
 565
 566                /* j is the first uninteresting line and there is
 567                 * no overlap beyond it within context lines.  Paint
 568                 * the trailing edge a bit.
 569                 */
 570                i = k;
 571                k = (j + context < cnt+1) ? j + context : cnt+1;
 572                while (j < k)
 573                        sline[j++].flag |= mark;
 574        }
 575        return 1;
 576}
 577
 578static int make_hunks(struct sline *sline, unsigned long cnt,
 579                       int num_parent, int dense)
 580{
 581        unsigned long all_mask = (1UL<<num_parent) - 1;
 582        unsigned long mark = (1UL<<num_parent);
 583        unsigned long i;
 584        int has_interesting = 0;
 585
 586        for (i = 0; i <= cnt; i++) {
 587                if (interesting(&sline[i], all_mask))
 588                        sline[i].flag |= mark;
 589                else
 590                        sline[i].flag &= ~mark;
 591        }
 592        if (!dense)
 593                return give_context(sline, cnt, num_parent);
 594
 595        /* Look at each hunk, and if we have changes from only one
 596         * parent, or the changes are the same from all but one
 597         * parent, mark that uninteresting.
 598         */
 599        i = 0;
 600        while (i <= cnt) {
 601                unsigned long j, hunk_begin, hunk_end;
 602                unsigned long same_diff;
 603                while (i <= cnt && !(sline[i].flag & mark))
 604                        i++;
 605                if (cnt < i)
 606                        break; /* No more interesting hunks */
 607                hunk_begin = i;
 608                for (j = i + 1; j <= cnt; j++) {
 609                        if (!(sline[j].flag & mark)) {
 610                                /* Look beyond the end to see if there
 611                                 * is an interesting line after this
 612                                 * hunk within context span.
 613                                 */
 614                                unsigned long la; /* lookahead */
 615                                int contin = 0;
 616                                la = adjust_hunk_tail(sline, all_mask,
 617                                                     hunk_begin, j);
 618                                la = (la + context < cnt + 1) ?
 619                                        (la + context) : cnt + 1;
 620                                while (la && j <= --la) {
 621                                        if (sline[la].flag & mark) {
 622                                                contin = 1;
 623                                                break;
 624                                        }
 625                                }
 626                                if (!contin)
 627                                        break;
 628                                j = la;
 629                        }
 630                }
 631                hunk_end = j;
 632
 633                /* [i..hunk_end) are interesting.  Now is it really
 634                 * interesting?  We check if there are only two versions
 635                 * and the result matches one of them.  That is, we look
 636                 * at:
 637                 *   (+) line, which records lines added to which parents;
 638                 *       this line appears in the result.
 639                 *   (-) line, which records from what parents the line
 640                 *       was removed; this line does not appear in the result.
 641                 * then check the set of parents the result has difference
 642                 * from, from all lines.  If there are lines that has
 643                 * different set of parents that the result has differences
 644                 * from, that means we have more than two versions.
 645                 *
 646                 * Even when we have only two versions, if the result does
 647                 * not match any of the parents, the it should be considered
 648                 * interesting.  In such a case, we would have all '+' line.
 649                 * After passing the above "two versions" test, that would
 650                 * appear as "the same set of parents" to be "all parents".
 651                 */
 652                same_diff = 0;
 653                has_interesting = 0;
 654                for (j = i; j < hunk_end && !has_interesting; j++) {
 655                        unsigned long this_diff = sline[j].flag & all_mask;
 656                        struct lline *ll = sline[j].lost;
 657                        if (this_diff) {
 658                                /* This has some changes.  Is it the
 659                                 * same as others?
 660                                 */
 661                                if (!same_diff)
 662                                        same_diff = this_diff;
 663                                else if (same_diff != this_diff) {
 664                                        has_interesting = 1;
 665                                        break;
 666                                }
 667                        }
 668                        while (ll && !has_interesting) {
 669                                /* Lost this line from these parents;
 670                                 * who are they?  Are they the same?
 671                                 */
 672                                this_diff = ll->parent_map;
 673                                if (!same_diff)
 674                                        same_diff = this_diff;
 675                                else if (same_diff != this_diff) {
 676                                        has_interesting = 1;
 677                                }
 678                                ll = ll->next;
 679                        }
 680                }
 681
 682                if (!has_interesting && same_diff != all_mask) {
 683                        /* This hunk is not that interesting after all */
 684                        for (j = hunk_begin; j < hunk_end; j++)
 685                                sline[j].flag &= ~mark;
 686                }
 687                i = hunk_end;
 688        }
 689
 690        has_interesting = give_context(sline, cnt, num_parent);
 691        return has_interesting;
 692}
 693
 694static void show_parent_lno(struct sline *sline, unsigned long l0, unsigned long l1, int n, unsigned long null_context)
 695{
 696        l0 = sline[l0].p_lno[n];
 697        l1 = sline[l1].p_lno[n];
 698        printf(" -%lu,%lu", l0, l1-l0-null_context);
 699}
 700
 701static int hunk_comment_line(const char *bol)
 702{
 703        int ch;
 704
 705        if (!bol)
 706                return 0;
 707        ch = *bol & 0xff;
 708        return (isalpha(ch) || ch == '_' || ch == '$');
 709}
 710
 711static void show_line_to_eol(const char *line, int len, const char *reset)
 712{
 713        int saw_cr_at_eol = 0;
 714        if (len < 0)
 715                len = strlen(line);
 716        saw_cr_at_eol = (len && line[len-1] == '\r');
 717
 718        printf("%.*s%s%s\n", len - saw_cr_at_eol, line,
 719               reset,
 720               saw_cr_at_eol ? "\r" : "");
 721}
 722
 723static void dump_sline(struct sline *sline, const char *line_prefix,
 724                       unsigned long cnt, int num_parent,
 725                       int use_color, int result_deleted)
 726{
 727        unsigned long mark = (1UL<<num_parent);
 728        unsigned long no_pre_delete = (2UL<<num_parent);
 729        int i;
 730        unsigned long lno = 0;
 731        const char *c_frag = diff_get_color(use_color, DIFF_FRAGINFO);
 732        const char *c_func = diff_get_color(use_color, DIFF_FUNCINFO);
 733        const char *c_new = diff_get_color(use_color, DIFF_FILE_NEW);
 734        const char *c_old = diff_get_color(use_color, DIFF_FILE_OLD);
 735        const char *c_context = diff_get_color(use_color, DIFF_CONTEXT);
 736        const char *c_reset = diff_get_color(use_color, DIFF_RESET);
 737
 738        if (result_deleted)
 739                return; /* result deleted */
 740
 741        while (1) {
 742                unsigned long hunk_end;
 743                unsigned long rlines;
 744                const char *hunk_comment = NULL;
 745                unsigned long null_context = 0;
 746
 747                while (lno <= cnt && !(sline[lno].flag & mark)) {
 748                        if (hunk_comment_line(sline[lno].bol))
 749                                hunk_comment = sline[lno].bol;
 750                        lno++;
 751                }
 752                if (cnt < lno)
 753                        break;
 754                else {
 755                        for (hunk_end = lno + 1; hunk_end <= cnt; hunk_end++)
 756                                if (!(sline[hunk_end].flag & mark))
 757                                        break;
 758                }
 759                rlines = hunk_end - lno;
 760                if (cnt < hunk_end)
 761                        rlines--; /* pointing at the last delete hunk */
 762
 763                if (!context) {
 764                        /*
 765                         * Even when running with --unified=0, all
 766                         * lines in the hunk needs to be processed in
 767                         * the loop below in order to show the
 768                         * deletion recorded in lost_head.  However,
 769                         * we do not want to show the resulting line
 770                         * with all blank context markers in such a
 771                         * case.  Compensate.
 772                         */
 773                        unsigned long j;
 774                        for (j = lno; j < hunk_end; j++)
 775                                if (!(sline[j].flag & (mark-1)))
 776                                        null_context++;
 777                        rlines -= null_context;
 778                }
 779
 780                printf("%s%s", line_prefix, c_frag);
 781                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 782                for (i = 0; i < num_parent; i++)
 783                        show_parent_lno(sline, lno, hunk_end, i, null_context);
 784                printf(" +%lu,%lu ", lno+1, rlines);
 785                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
 786
 787                if (hunk_comment) {
 788                        int comment_end = 0;
 789                        for (i = 0; i < 40; i++) {
 790                                int ch = hunk_comment[i] & 0xff;
 791                                if (!ch || ch == '\n')
 792                                        break;
 793                                if (!isspace(ch))
 794                                    comment_end = i;
 795                        }
 796                        if (comment_end)
 797                                printf("%s%s %s%s", c_reset,
 798                                                    c_context, c_reset,
 799                                                    c_func);
 800                        for (i = 0; i < comment_end; i++)
 801                                putchar(hunk_comment[i]);
 802                }
 803
 804                printf("%s\n", c_reset);
 805                while (lno < hunk_end) {
 806                        struct lline *ll;
 807                        int j;
 808                        unsigned long p_mask;
 809                        struct sline *sl = &sline[lno++];
 810                        ll = (sl->flag & no_pre_delete) ? NULL : sl->lost;
 811                        while (ll) {
 812                                printf("%s%s", line_prefix, c_old);
 813                                for (j = 0; j < num_parent; j++) {
 814                                        if (ll->parent_map & (1UL<<j))
 815                                                putchar('-');
 816                                        else
 817                                                putchar(' ');
 818                                }
 819                                show_line_to_eol(ll->line, -1, c_reset);
 820                                ll = ll->next;
 821                        }
 822                        if (cnt < lno)
 823                                break;
 824                        p_mask = 1;
 825                        fputs(line_prefix, stdout);
 826                        if (!(sl->flag & (mark-1))) {
 827                                /*
 828                                 * This sline was here to hang the
 829                                 * lost lines in front of it.
 830                                 */
 831                                if (!context)
 832                                        continue;
 833                                fputs(c_context, stdout);
 834                        }
 835                        else
 836                                fputs(c_new, stdout);
 837                        for (j = 0; j < num_parent; j++) {
 838                                if (p_mask & sl->flag)
 839                                        putchar('+');
 840                                else
 841                                        putchar(' ');
 842                                p_mask <<= 1;
 843                        }
 844                        show_line_to_eol(sl->bol, sl->len, c_reset);
 845                }
 846        }
 847}
 848
 849static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
 850                               int i, int j)
 851{
 852        /* We have already examined parent j and we know parent i
 853         * and parent j are the same, so reuse the combined result
 854         * of parent j for parent i.
 855         */
 856        unsigned long lno, imask, jmask;
 857        imask = (1UL<<i);
 858        jmask = (1UL<<j);
 859
 860        for (lno = 0; lno <= cnt; lno++) {
 861                struct lline *ll = sline->lost;
 862                sline->p_lno[i] = sline->p_lno[j];
 863                while (ll) {
 864                        if (ll->parent_map & jmask)
 865                                ll->parent_map |= imask;
 866                        ll = ll->next;
 867                }
 868                if (sline->flag & jmask)
 869                        sline->flag |= imask;
 870                sline++;
 871        }
 872        /* the overall size of the file (sline[cnt]) */
 873        sline->p_lno[i] = sline->p_lno[j];
 874}
 875
 876static void dump_quoted_path(const char *head,
 877                             const char *prefix,
 878                             const char *path,
 879                             const char *line_prefix,
 880                             const char *c_meta, const char *c_reset)
 881{
 882        static struct strbuf buf = STRBUF_INIT;
 883
 884        strbuf_reset(&buf);
 885        strbuf_addstr(&buf, line_prefix);
 886        strbuf_addstr(&buf, c_meta);
 887        strbuf_addstr(&buf, head);
 888        quote_two_c_style(&buf, prefix, path, 0);
 889        strbuf_addstr(&buf, c_reset);
 890        puts(buf.buf);
 891}
 892
 893static void show_combined_header(struct combine_diff_path *elem,
 894                                 int num_parent,
 895                                 int dense,
 896                                 struct rev_info *rev,
 897                                 const char *line_prefix,
 898                                 int mode_differs,
 899                                 int show_file_header)
 900{
 901        struct diff_options *opt = &rev->diffopt;
 902        int abbrev = opt->flags.full_index ? GIT_SHA1_HEXSZ : DEFAULT_ABBREV;
 903        const char *a_prefix = opt->a_prefix ? opt->a_prefix : "a/";
 904        const char *b_prefix = opt->b_prefix ? opt->b_prefix : "b/";
 905        const char *c_meta = diff_get_color_opt(opt, DIFF_METAINFO);
 906        const char *c_reset = diff_get_color_opt(opt, DIFF_RESET);
 907        const char *abb;
 908        int added = 0;
 909        int deleted = 0;
 910        int i;
 911
 912        if (rev->loginfo && !rev->no_commit_id)
 913                show_log(rev);
 914
 915        dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
 916                         "", elem->path, line_prefix, c_meta, c_reset);
 917        printf("%s%sindex ", line_prefix, c_meta);
 918        for (i = 0; i < num_parent; i++) {
 919                abb = find_unique_abbrev(&elem->parent[i].oid,
 920                                         abbrev);
 921                printf("%s%s", i ? "," : "", abb);
 922        }
 923        abb = find_unique_abbrev(&elem->oid, abbrev);
 924        printf("..%s%s\n", abb, c_reset);
 925
 926        if (mode_differs) {
 927                deleted = !elem->mode;
 928
 929                /* We say it was added if nobody had it */
 930                added = !deleted;
 931                for (i = 0; added && i < num_parent; i++)
 932                        if (elem->parent[i].status !=
 933                            DIFF_STATUS_ADDED)
 934                                added = 0;
 935                if (added)
 936                        printf("%s%snew file mode %06o",
 937                               line_prefix, c_meta, elem->mode);
 938                else {
 939                        if (deleted)
 940                                printf("%s%sdeleted file ",
 941                                       line_prefix, c_meta);
 942                        printf("mode ");
 943                        for (i = 0; i < num_parent; i++) {
 944                                printf("%s%06o", i ? "," : "",
 945                                       elem->parent[i].mode);
 946                        }
 947                        if (elem->mode)
 948                                printf("..%06o", elem->mode);
 949                }
 950                printf("%s\n", c_reset);
 951        }
 952
 953        if (!show_file_header)
 954                return;
 955
 956        if (added)
 957                dump_quoted_path("--- ", "", "/dev/null",
 958                                 line_prefix, c_meta, c_reset);
 959        else
 960                dump_quoted_path("--- ", a_prefix, elem->path,
 961                                 line_prefix, c_meta, c_reset);
 962        if (deleted)
 963                dump_quoted_path("+++ ", "", "/dev/null",
 964                                 line_prefix, c_meta, c_reset);
 965        else
 966                dump_quoted_path("+++ ", b_prefix, elem->path,
 967                                 line_prefix, c_meta, c_reset);
 968}
 969
 970static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
 971                            int dense, int working_tree_file,
 972                            struct rev_info *rev)
 973{
 974        struct diff_options *opt = &rev->diffopt;
 975        unsigned long result_size, cnt, lno;
 976        int result_deleted = 0;
 977        char *result, *cp;
 978        struct sline *sline; /* survived lines */
 979        int mode_differs = 0;
 980        int i, show_hunks;
 981        mmfile_t result_file;
 982        struct userdiff_driver *userdiff;
 983        struct userdiff_driver *textconv = NULL;
 984        int is_binary;
 985        const char *line_prefix = diff_line_prefix(opt);
 986
 987        context = opt->context;
 988        userdiff = userdiff_find_by_path(elem->path);
 989        if (!userdiff)
 990                userdiff = userdiff_find_by_name("default");
 991        if (opt->flags.allow_textconv)
 992                textconv = userdiff_get_textconv(userdiff);
 993
 994        /* Read the result of merge first */
 995        if (!working_tree_file)
 996                result = grab_blob(&elem->oid, elem->mode, &result_size,
 997                                   textconv, elem->path);
 998        else {
 999                /* Used by diff-tree to read from the working tree */
1000                struct stat st;
1001                int fd = -1;
1002
1003                if (lstat(elem->path, &st) < 0)
1004                        goto deleted_file;
1005
1006                if (S_ISLNK(st.st_mode)) {
1007                        struct strbuf buf = STRBUF_INIT;
1008
1009                        if (strbuf_readlink(&buf, elem->path, st.st_size) < 0) {
1010                                error_errno("readlink(%s)", elem->path);
1011                                return;
1012                        }
1013                        result_size = buf.len;
1014                        result = strbuf_detach(&buf, NULL);
1015                        elem->mode = canon_mode(st.st_mode);
1016                } else if (S_ISDIR(st.st_mode)) {
1017                        struct object_id oid;
1018                        if (resolve_gitlink_ref(elem->path, "HEAD", &oid) < 0)
1019                                result = grab_blob(&elem->oid, elem->mode,
1020                                                   &result_size, NULL, NULL);
1021                        else
1022                                result = grab_blob(&oid, elem->mode,
1023                                                   &result_size, NULL, NULL);
1024                } else if (textconv) {
1025                        struct diff_filespec *df = alloc_filespec(elem->path);
1026                        fill_filespec(df, &null_oid, 0, st.st_mode);
1027                        result_size = fill_textconv(textconv, df, &result);
1028                        free_filespec(df);
1029                } else if (0 <= (fd = open(elem->path, O_RDONLY))) {
1030                        size_t len = xsize_t(st.st_size);
1031                        ssize_t done;
1032                        int is_file, i;
1033
1034                        elem->mode = canon_mode(st.st_mode);
1035                        /* if symlinks don't work, assume symlink if all parents
1036                         * are symlinks
1037                         */
1038                        is_file = has_symlinks;
1039                        for (i = 0; !is_file && i < num_parent; i++)
1040                                is_file = !S_ISLNK(elem->parent[i].mode);
1041                        if (!is_file)
1042                                elem->mode = canon_mode(S_IFLNK);
1043
1044                        result_size = len;
1045                        result = xmallocz(len);
1046
1047                        done = read_in_full(fd, result, len);
1048                        if (done < 0)
1049                                die_errno("read error '%s'", elem->path);
1050                        else if (done < len)
1051                                die("early EOF '%s'", elem->path);
1052
1053                        /* If not a fake symlink, apply filters, e.g. autocrlf */
1054                        if (is_file) {
1055                                struct strbuf buf = STRBUF_INIT;
1056
1057                                if (convert_to_git(&the_index, elem->path, result, len, &buf, global_conv_flags_eol)) {
1058                                        free(result);
1059                                        result = strbuf_detach(&buf, &len);
1060                                        result_size = len;
1061                                }
1062                        }
1063                }
1064                else {
1065                deleted_file:
1066                        result_deleted = 1;
1067                        result_size = 0;
1068                        elem->mode = 0;
1069                        result = xcalloc(1, 1);
1070                }
1071
1072                if (0 <= fd)
1073                        close(fd);
1074        }
1075
1076        for (i = 0; i < num_parent; i++) {
1077                if (elem->parent[i].mode != elem->mode) {
1078                        mode_differs = 1;
1079                        break;
1080                }
1081        }
1082
1083        if (textconv)
1084                is_binary = 0;
1085        else if (userdiff->binary != -1)
1086                is_binary = userdiff->binary;
1087        else {
1088                is_binary = buffer_is_binary(result, result_size);
1089                for (i = 0; !is_binary && i < num_parent; i++) {
1090                        char *buf;
1091                        unsigned long size;
1092                        buf = grab_blob(&elem->parent[i].oid,
1093                                        elem->parent[i].mode,
1094                                        &size, NULL, NULL);
1095                        if (buffer_is_binary(buf, size))
1096                                is_binary = 1;
1097                        free(buf);
1098                }
1099        }
1100        if (is_binary) {
1101                show_combined_header(elem, num_parent, dense, rev,
1102                                     line_prefix, mode_differs, 0);
1103                printf("Binary files differ\n");
1104                free(result);
1105                return;
1106        }
1107
1108        for (cnt = 0, cp = result; cp < result + result_size; cp++) {
1109                if (*cp == '\n')
1110                        cnt++;
1111        }
1112        if (result_size && result[result_size-1] != '\n')
1113                cnt++; /* incomplete line */
1114
1115        sline = xcalloc(st_add(cnt, 2), sizeof(*sline));
1116        sline[0].bol = result;
1117        for (lno = 0, cp = result; cp < result + result_size; cp++) {
1118                if (*cp == '\n') {
1119                        sline[lno].len = cp - sline[lno].bol;
1120                        lno++;
1121                        if (lno < cnt)
1122                                sline[lno].bol = cp + 1;
1123                }
1124        }
1125        if (result_size && result[result_size-1] != '\n')
1126                sline[cnt-1].len = result_size - (sline[cnt-1].bol - result);
1127
1128        result_file.ptr = result;
1129        result_file.size = result_size;
1130
1131        /* Even p_lno[cnt+1] is valid -- that is for the end line number
1132         * for deletion hunk at the end.
1133         */
1134        sline[0].p_lno = xcalloc(st_mult(st_add(cnt, 2), num_parent), sizeof(unsigned long));
1135        for (lno = 0; lno <= cnt; lno++)
1136                sline[lno+1].p_lno = sline[lno].p_lno + num_parent;
1137
1138        for (i = 0; i < num_parent; i++) {
1139                int j;
1140                for (j = 0; j < i; j++) {
1141                        if (oideq(&elem->parent[i].oid,
1142                                  &elem->parent[j].oid)) {
1143                                reuse_combine_diff(sline, cnt, i, j);
1144                                break;
1145                        }
1146                }
1147                if (i <= j)
1148                        combine_diff(&elem->parent[i].oid,
1149                                     elem->parent[i].mode,
1150                                     &result_file, sline,
1151                                     cnt, i, num_parent, result_deleted,
1152                                     textconv, elem->path, opt->xdl_opts);
1153        }
1154
1155        show_hunks = make_hunks(sline, cnt, num_parent, dense);
1156
1157        if (show_hunks || mode_differs || working_tree_file) {
1158                show_combined_header(elem, num_parent, dense, rev,
1159                                     line_prefix, mode_differs, 1);
1160                dump_sline(sline, line_prefix, cnt, num_parent,
1161                           opt->use_color, result_deleted);
1162        }
1163        free(result);
1164
1165        for (lno = 0; lno < cnt; lno++) {
1166                if (sline[lno].lost) {
1167                        struct lline *ll = sline[lno].lost;
1168                        while (ll) {
1169                                struct lline *tmp = ll;
1170                                ll = ll->next;
1171                                free(tmp);
1172                        }
1173                }
1174        }
1175        free(sline[0].p_lno);
1176        free(sline);
1177}
1178
1179static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct rev_info *rev)
1180{
1181        struct diff_options *opt = &rev->diffopt;
1182        int line_termination, inter_name_termination, i;
1183        const char *line_prefix = diff_line_prefix(opt);
1184
1185        line_termination = opt->line_termination;
1186        inter_name_termination = '\t';
1187        if (!line_termination)
1188                inter_name_termination = 0;
1189
1190        if (rev->loginfo && !rev->no_commit_id)
1191                show_log(rev);
1192
1193
1194        if (opt->output_format & DIFF_FORMAT_RAW) {
1195                printf("%s", line_prefix);
1196
1197                /* As many colons as there are parents */
1198                for (i = 0; i < num_parent; i++)
1199                        putchar(':');
1200
1201                /* Show the modes */
1202                for (i = 0; i < num_parent; i++)
1203                        printf("%06o ", p->parent[i].mode);
1204                printf("%06o", p->mode);
1205
1206                /* Show sha1's */
1207                for (i = 0; i < num_parent; i++)
1208                        printf(" %s", diff_aligned_abbrev(&p->parent[i].oid,
1209                                                          opt->abbrev));
1210                printf(" %s ", diff_aligned_abbrev(&p->oid, opt->abbrev));
1211        }
1212
1213        if (opt->output_format & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS)) {
1214                for (i = 0; i < num_parent; i++)
1215                        putchar(p->parent[i].status);
1216                putchar(inter_name_termination);
1217        }
1218
1219        write_name_quoted(p->path, stdout, line_termination);
1220}
1221
1222/*
1223 * The result (p->elem) is from the working tree and their
1224 * parents are typically from multiple stages during a merge
1225 * (i.e. diff-files) or the state in HEAD and in the index
1226 * (i.e. diff-index).
1227 */
1228void show_combined_diff(struct combine_diff_path *p,
1229                       int num_parent,
1230                       int dense,
1231                       struct rev_info *rev)
1232{
1233        struct diff_options *opt = &rev->diffopt;
1234
1235        if (opt->output_format & (DIFF_FORMAT_RAW |
1236                                  DIFF_FORMAT_NAME |
1237                                  DIFF_FORMAT_NAME_STATUS))
1238                show_raw_diff(p, num_parent, rev);
1239        else if (opt->output_format & DIFF_FORMAT_PATCH)
1240                show_patch_diff(p, num_parent, dense, 1, rev);
1241}
1242
1243static void free_combined_pair(struct diff_filepair *pair)
1244{
1245        free(pair->two);
1246        free(pair);
1247}
1248
1249/*
1250 * A combine_diff_path expresses N parents on the LHS against 1 merge
1251 * result. Synthesize a diff_filepair that has N entries on the "one"
1252 * side and 1 entry on the "two" side.
1253 *
1254 * In the future, we might want to add more data to combine_diff_path
1255 * so that we can fill fields we are ignoring (most notably, size) here,
1256 * but currently nobody uses it, so this should suffice for now.
1257 */
1258static struct diff_filepair *combined_pair(struct combine_diff_path *p,
1259                                           int num_parent)
1260{
1261        int i;
1262        struct diff_filepair *pair;
1263        struct diff_filespec *pool;
1264
1265        pair = xmalloc(sizeof(*pair));
1266        pool = xcalloc(st_add(num_parent, 1), sizeof(struct diff_filespec));
1267        pair->one = pool + 1;
1268        pair->two = pool;
1269
1270        for (i = 0; i < num_parent; i++) {
1271                pair->one[i].path = p->path;
1272                pair->one[i].mode = p->parent[i].mode;
1273                oidcpy(&pair->one[i].oid, &p->parent[i].oid);
1274                pair->one[i].oid_valid = !is_null_oid(&p->parent[i].oid);
1275                pair->one[i].has_more_entries = 1;
1276        }
1277        pair->one[num_parent - 1].has_more_entries = 0;
1278
1279        pair->two->path = p->path;
1280        pair->two->mode = p->mode;
1281        oidcpy(&pair->two->oid, &p->oid);
1282        pair->two->oid_valid = !is_null_oid(&p->oid);
1283        return pair;
1284}
1285
1286static void handle_combined_callback(struct diff_options *opt,
1287                                     struct combine_diff_path *paths,
1288                                     int num_parent,
1289                                     int num_paths)
1290{
1291        struct combine_diff_path *p;
1292        struct diff_queue_struct q;
1293        int i;
1294
1295        q.queue = xcalloc(num_paths, sizeof(struct diff_filepair *));
1296        q.alloc = num_paths;
1297        q.nr = num_paths;
1298        for (i = 0, p = paths; p; p = p->next)
1299                q.queue[i++] = combined_pair(p, num_parent);
1300        opt->format_callback(&q, opt, opt->format_callback_data);
1301        for (i = 0; i < num_paths; i++)
1302                free_combined_pair(q.queue[i]);
1303        free(q.queue);
1304}
1305
1306static const char *path_path(void *obj)
1307{
1308        struct combine_diff_path *path = (struct combine_diff_path *)obj;
1309
1310        return path->path;
1311}
1312
1313
1314/* find set of paths that every parent touches */
1315static struct combine_diff_path *find_paths_generic(const struct object_id *oid,
1316        const struct oid_array *parents, struct diff_options *opt)
1317{
1318        struct combine_diff_path *paths = NULL;
1319        int i, num_parent = parents->nr;
1320
1321        int output_format = opt->output_format;
1322        const char *orderfile = opt->orderfile;
1323
1324        opt->output_format = DIFF_FORMAT_NO_OUTPUT;
1325        /* tell diff_tree to emit paths in sorted (=tree) order */
1326        opt->orderfile = NULL;
1327
1328        /* D(A,P1...Pn) = D(A,P1) ^ ... ^ D(A,Pn)  (wrt paths) */
1329        for (i = 0; i < num_parent; i++) {
1330                /*
1331                 * show stat against the first parent even when doing
1332                 * combined diff.
1333                 */
1334                int stat_opt = (output_format &
1335                                (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
1336                if (i == 0 && stat_opt)
1337                        opt->output_format = stat_opt;
1338                else
1339                        opt->output_format = DIFF_FORMAT_NO_OUTPUT;
1340                diff_tree_oid(&parents->oid[i], oid, "", opt);
1341                diffcore_std(opt);
1342                paths = intersect_paths(paths, i, num_parent);
1343
1344                /* if showing diff, show it in requested order */
1345                if (opt->output_format != DIFF_FORMAT_NO_OUTPUT &&
1346                    orderfile) {
1347                        diffcore_order(orderfile);
1348                }
1349
1350                diff_flush(opt);
1351        }
1352
1353        opt->output_format = output_format;
1354        opt->orderfile = orderfile;
1355        return paths;
1356}
1357
1358
1359/*
1360 * find set of paths that everybody touches, assuming diff is run without
1361 * rename/copy detection, etc, comparing all trees simultaneously (= faster).
1362 */
1363static struct combine_diff_path *find_paths_multitree(
1364        const struct object_id *oid, const struct oid_array *parents,
1365        struct diff_options *opt)
1366{
1367        int i, nparent = parents->nr;
1368        const struct object_id **parents_oid;
1369        struct combine_diff_path paths_head;
1370        struct strbuf base;
1371
1372        ALLOC_ARRAY(parents_oid, nparent);
1373        for (i = 0; i < nparent; i++)
1374                parents_oid[i] = &parents->oid[i];
1375
1376        /* fake list head, so worker can assume it is non-NULL */
1377        paths_head.next = NULL;
1378
1379        strbuf_init(&base, PATH_MAX);
1380        diff_tree_paths(&paths_head, oid, parents_oid, nparent, &base, opt);
1381
1382        strbuf_release(&base);
1383        free(parents_oid);
1384        return paths_head.next;
1385}
1386
1387
1388void diff_tree_combined(const struct object_id *oid,
1389                        const struct oid_array *parents,
1390                        int dense,
1391                        struct rev_info *rev)
1392{
1393        struct diff_options *opt = &rev->diffopt;
1394        struct diff_options diffopts;
1395        struct combine_diff_path *p, *paths;
1396        int i, num_paths, needsep, show_log_first, num_parent = parents->nr;
1397        int need_generic_pathscan;
1398
1399        /* nothing to do, if no parents */
1400        if (!num_parent)
1401                return;
1402
1403        show_log_first = !!rev->loginfo && !rev->no_commit_id;
1404        needsep = 0;
1405        if (show_log_first) {
1406                show_log(rev);
1407
1408                if (rev->verbose_header && opt->output_format &&
1409                    opt->output_format != DIFF_FORMAT_NO_OUTPUT &&
1410                    !commit_format_is_empty(rev->commit_format))
1411                        printf("%s%c", diff_line_prefix(opt),
1412                               opt->line_termination);
1413        }
1414
1415        diffopts = *opt;
1416        copy_pathspec(&diffopts.pathspec, &opt->pathspec);
1417        diffopts.flags.recursive = 1;
1418        diffopts.flags.allow_external = 0;
1419
1420        /* find set of paths that everybody touches
1421         *
1422         * NOTE
1423         *
1424         * Diffcore transformations are bound to diff_filespec and logic
1425         * comparing two entries - i.e. they do not apply directly to combine
1426         * diff.
1427         *
1428         * If some of such transformations is requested - we launch generic
1429         * path scanning, which works significantly slower compared to
1430         * simultaneous all-trees-in-one-go scan in find_paths_multitree().
1431         *
1432         * TODO some of the filters could be ported to work on
1433         * combine_diff_paths - i.e. all functionality that skips paths, so in
1434         * theory, we could end up having only multitree path scanning.
1435         *
1436         * NOTE please keep this semantically in sync with diffcore_std()
1437         */
1438        need_generic_pathscan = opt->skip_stat_unmatch  ||
1439                        opt->flags.follow_renames       ||
1440                        opt->break_opt != -1    ||
1441                        opt->detect_rename      ||
1442                        (opt->pickaxe_opts & DIFF_PICKAXE_KINDS_MASK)   ||
1443                        opt->filter;
1444
1445
1446        if (need_generic_pathscan) {
1447                /*
1448                 * NOTE generic case also handles --stat, as it computes
1449                 * diff(sha1,parent_i) for all i to do the job, specifically
1450                 * for parent0.
1451                 */
1452                paths = find_paths_generic(oid, parents, &diffopts);
1453        }
1454        else {
1455                int stat_opt;
1456                paths = find_paths_multitree(oid, parents, &diffopts);
1457
1458                /*
1459                 * show stat against the first parent even
1460                 * when doing combined diff.
1461                 */
1462                stat_opt = (opt->output_format &
1463                                (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
1464                if (stat_opt) {
1465                        diffopts.output_format = stat_opt;
1466
1467                        diff_tree_oid(&parents->oid[0], oid, "", &diffopts);
1468                        diffcore_std(&diffopts);
1469                        if (opt->orderfile)
1470                                diffcore_order(opt->orderfile);
1471                        diff_flush(&diffopts);
1472                }
1473        }
1474
1475        /* find out number of surviving paths */
1476        for (num_paths = 0, p = paths; p; p = p->next)
1477                num_paths++;
1478
1479        /* order paths according to diffcore_order */
1480        if (opt->orderfile && num_paths) {
1481                struct obj_order *o;
1482
1483                ALLOC_ARRAY(o, num_paths);
1484                for (i = 0, p = paths; p; p = p->next, i++)
1485                        o[i].obj = p;
1486                order_objects(opt->orderfile, path_path, o, num_paths);
1487                for (i = 0; i < num_paths - 1; i++) {
1488                        p = o[i].obj;
1489                        p->next = o[i+1].obj;
1490                }
1491
1492                p = o[num_paths-1].obj;
1493                p->next = NULL;
1494                paths = o[0].obj;
1495                free(o);
1496        }
1497
1498
1499        if (num_paths) {
1500                if (opt->output_format & (DIFF_FORMAT_RAW |
1501                                          DIFF_FORMAT_NAME |
1502                                          DIFF_FORMAT_NAME_STATUS)) {
1503                        for (p = paths; p; p = p->next)
1504                                show_raw_diff(p, num_parent, rev);
1505                        needsep = 1;
1506                }
1507                else if (opt->output_format &
1508                         (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT))
1509                        needsep = 1;
1510                else if (opt->output_format & DIFF_FORMAT_CALLBACK)
1511                        handle_combined_callback(opt, paths, num_parent, num_paths);
1512
1513                if (opt->output_format & DIFF_FORMAT_PATCH) {
1514                        if (needsep)
1515                                printf("%s%c", diff_line_prefix(opt),
1516                                       opt->line_termination);
1517                        for (p = paths; p; p = p->next)
1518                                show_patch_diff(p, num_parent, dense,
1519                                                0, rev);
1520                }
1521        }
1522
1523        /* Clean things up */
1524        while (paths) {
1525                struct combine_diff_path *tmp = paths;
1526                paths = paths->next;
1527                free(tmp);
1528        }
1529
1530        clear_pathspec(&diffopts.pathspec);
1531}
1532
1533void diff_tree_combined_merge(const struct commit *commit, int dense,
1534                              struct rev_info *rev)
1535{
1536        struct commit_list *parent = get_saved_parents(rev, commit);
1537        struct oid_array parents = OID_ARRAY_INIT;
1538
1539        while (parent) {
1540                oid_array_append(&parents, &parent->item->object.oid);
1541                parent = parent->next;
1542        }
1543        diff_tree_combined(&commit->object.oid, &parents, dense, rev);
1544        oid_array_clear(&parents);
1545}