Andrew's git / gitweb.git / commit.c
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commit.con commit Merge branch 'jc/apply' into next (b312cc8)
   1#include "cache.h"
   2#include "tag.h"
   3#include "commit.h"
   4
   5int save_commit_buffer = 1;
   6
   7struct sort_node
   8{
   9        /*
  10         * the number of children of the associated commit
  11         * that also occur in the list being sorted.
  12         */
  13        unsigned int indegree;
  14
  15        /*
  16         * reference to original list item that we will re-use
  17         * on output.
  18         */
  19        struct commit_list * list_item;
  20
  21};
  22
  23const char *commit_type = "commit";
  24
  25struct cmt_fmt_map {
  26        const char *n;
  27        size_t cmp_len;
  28        enum cmit_fmt v;
  29} cmt_fmts[] = {
  30        { "raw",        1,      CMIT_FMT_RAW },
  31        { "medium",     1,      CMIT_FMT_MEDIUM },
  32        { "short",      1,      CMIT_FMT_SHORT },
  33        { "email",      1,      CMIT_FMT_EMAIL },
  34        { "full",       5,      CMIT_FMT_FULL },
  35        { "fuller",     5,      CMIT_FMT_FULLER },
  36        { "oneline",    1,      CMIT_FMT_ONELINE },
  37};
  38
  39enum cmit_fmt get_commit_format(const char *arg)
  40{
  41        int i;
  42
  43        if (!arg || !*arg)
  44                return CMIT_FMT_DEFAULT;
  45        if (*arg == '=')
  46                arg++;
  47        for (i = 0; i < ARRAY_SIZE(cmt_fmts); i++) {
  48                if (!strncmp(arg, cmt_fmts[i].n, cmt_fmts[i].cmp_len))
  49                        return cmt_fmts[i].v;
  50        }
  51
  52        die("invalid --pretty format: %s", arg);
  53}
  54
  55static struct commit *check_commit(struct object *obj,
  56                                   const unsigned char *sha1,
  57                                   int quiet)
  58{
  59        if (obj->type != commit_type) {
  60                if (!quiet)
  61                        error("Object %s is a %s, not a commit",
  62                              sha1_to_hex(sha1), obj->type);
  63                return NULL;
  64        }
  65        return (struct commit *) obj;
  66}
  67
  68struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
  69                                              int quiet)
  70{
  71        struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
  72
  73        if (!obj)
  74                return NULL;
  75        return check_commit(obj, sha1, quiet);
  76}
  77
  78struct commit *lookup_commit_reference(const unsigned char *sha1)
  79{
  80        return lookup_commit_reference_gently(sha1, 0);
  81}
  82
  83struct commit *lookup_commit(const unsigned char *sha1)
  84{
  85        struct object *obj = lookup_object(sha1);
  86        if (!obj) {
  87                struct commit *ret = xcalloc(1, sizeof(struct commit));
  88                created_object(sha1, &ret->object);
  89                ret->object.type = commit_type;
  90                return ret;
  91        }
  92        if (!obj->type)
  93                obj->type = commit_type;
  94        return check_commit(obj, sha1, 0);
  95}
  96
  97static unsigned long parse_commit_date(const char *buf)
  98{
  99        unsigned long date;
 100
 101        if (memcmp(buf, "author", 6))
 102                return 0;
 103        while (*buf++ != '\n')
 104                /* nada */;
 105        if (memcmp(buf, "committer", 9))
 106                return 0;
 107        while (*buf++ != '>')
 108                /* nada */;
 109        date = strtoul(buf, NULL, 10);
 110        if (date == ULONG_MAX)
 111                date = 0;
 112        return date;
 113}
 114
 115static struct commit_graft **commit_graft;
 116static int commit_graft_alloc, commit_graft_nr;
 117
 118static int commit_graft_pos(const unsigned char *sha1)
 119{
 120        int lo, hi;
 121        lo = 0;
 122        hi = commit_graft_nr;
 123        while (lo < hi) {
 124                int mi = (lo + hi) / 2;
 125                struct commit_graft *graft = commit_graft[mi];
 126                int cmp = memcmp(sha1, graft->sha1, 20);
 127                if (!cmp)
 128                        return mi;
 129                if (cmp < 0)
 130                        hi = mi;
 131                else
 132                        lo = mi + 1;
 133        }
 134        return -lo - 1;
 135}
 136
 137int register_commit_graft(struct commit_graft *graft, int ignore_dups)
 138{
 139        int pos = commit_graft_pos(graft->sha1);
 140        
 141        if (0 <= pos) {
 142                if (ignore_dups)
 143                        free(graft);
 144                else {
 145                        free(commit_graft[pos]);
 146                        commit_graft[pos] = graft;
 147                }
 148                return 1;
 149        }
 150        pos = -pos - 1;
 151        if (commit_graft_alloc <= ++commit_graft_nr) {
 152                commit_graft_alloc = alloc_nr(commit_graft_alloc);
 153                commit_graft = xrealloc(commit_graft,
 154                                        sizeof(*commit_graft) *
 155                                        commit_graft_alloc);
 156        }
 157        if (pos < commit_graft_nr)
 158                memmove(commit_graft + pos + 1,
 159                        commit_graft + pos,
 160                        (commit_graft_nr - pos - 1) *
 161                        sizeof(*commit_graft));
 162        commit_graft[pos] = graft;
 163        return 0;
 164}
 165
 166struct commit_graft *read_graft_line(char *buf, int len)
 167{
 168        /* The format is just "Commit Parent1 Parent2 ...\n" */
 169        int i;
 170        struct commit_graft *graft = NULL;
 171
 172        if (buf[len-1] == '\n')
 173                buf[--len] = 0;
 174        if (buf[0] == '#' || buf[0] == '\0')
 175                return NULL;
 176        if ((len + 1) % 41) {
 177        bad_graft_data:
 178                error("bad graft data: %s", buf);
 179                free(graft);
 180                return NULL;
 181        }
 182        i = (len + 1) / 41 - 1;
 183        graft = xmalloc(sizeof(*graft) + 20 * i);
 184        graft->nr_parent = i;
 185        if (get_sha1_hex(buf, graft->sha1))
 186                goto bad_graft_data;
 187        for (i = 40; i < len; i += 41) {
 188                if (buf[i] != ' ')
 189                        goto bad_graft_data;
 190                if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
 191                        goto bad_graft_data;
 192        }
 193        return graft;
 194}
 195
 196int read_graft_file(const char *graft_file)
 197{
 198        FILE *fp = fopen(graft_file, "r");
 199        char buf[1024];
 200        if (!fp)
 201                return -1;
 202        while (fgets(buf, sizeof(buf), fp)) {
 203                /* The format is just "Commit Parent1 Parent2 ...\n" */
 204                int len = strlen(buf);
 205                struct commit_graft *graft = read_graft_line(buf, len);
 206                if (!graft)
 207                        continue;
 208                if (register_commit_graft(graft, 1))
 209                        error("duplicate graft data: %s", buf);
 210        }
 211        fclose(fp);
 212        return 0;
 213}
 214
 215static void prepare_commit_graft(void)
 216{
 217        static int commit_graft_prepared;
 218        char *graft_file;
 219
 220        if (commit_graft_prepared)
 221                return;
 222        graft_file = get_graft_file();
 223        read_graft_file(graft_file);
 224        commit_graft_prepared = 1;
 225}
 226
 227static struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
 228{
 229        int pos;
 230        prepare_commit_graft();
 231        pos = commit_graft_pos(sha1);
 232        if (pos < 0)
 233                return NULL;
 234        return commit_graft[pos];
 235}
 236
 237int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
 238{
 239        char *bufptr = buffer;
 240        unsigned char parent[20];
 241        struct commit_list **pptr;
 242        struct commit_graft *graft;
 243        unsigned n_refs = 0;
 244
 245        if (item->object.parsed)
 246                return 0;
 247        item->object.parsed = 1;
 248        if (memcmp(bufptr, "tree ", 5))
 249                return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
 250        if (get_sha1_hex(bufptr + 5, parent) < 0)
 251                return error("bad tree pointer in commit %s",
 252                             sha1_to_hex(item->object.sha1));
 253        item->tree = lookup_tree(parent);
 254        if (item->tree)
 255                n_refs++;
 256        bufptr += 46; /* "tree " + "hex sha1" + "\n" */
 257        pptr = &item->parents;
 258
 259        graft = lookup_commit_graft(item->object.sha1);
 260        while (!memcmp(bufptr, "parent ", 7)) {
 261                struct commit *new_parent;
 262
 263                if (get_sha1_hex(bufptr + 7, parent) || bufptr[47] != '\n')
 264                        return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
 265                bufptr += 48;
 266                if (graft)
 267                        continue;
 268                new_parent = lookup_commit(parent);
 269                if (new_parent) {
 270                        pptr = &commit_list_insert(new_parent, pptr)->next;
 271                        n_refs++;
 272                }
 273        }
 274        if (graft) {
 275                int i;
 276                struct commit *new_parent;
 277                for (i = 0; i < graft->nr_parent; i++) {
 278                        new_parent = lookup_commit(graft->parent[i]);
 279                        if (!new_parent)
 280                                continue;
 281                        pptr = &commit_list_insert(new_parent, pptr)->next;
 282                        n_refs++;
 283                }
 284        }
 285        item->date = parse_commit_date(bufptr);
 286
 287        if (track_object_refs) {
 288                unsigned i = 0;
 289                struct commit_list *p;
 290                struct object_refs *refs = alloc_object_refs(n_refs);
 291                if (item->tree)
 292                        refs->ref[i++] = &item->tree->object;
 293                for (p = item->parents; p; p = p->next)
 294                        refs->ref[i++] = &p->item->object;
 295                set_object_refs(&item->object, refs);
 296        }
 297
 298        return 0;
 299}
 300
 301int parse_commit(struct commit *item)
 302{
 303        char type[20];
 304        void *buffer;
 305        unsigned long size;
 306        int ret;
 307
 308        if (item->object.parsed)
 309                return 0;
 310        buffer = read_sha1_file(item->object.sha1, type, &size);
 311        if (!buffer)
 312                return error("Could not read %s",
 313                             sha1_to_hex(item->object.sha1));
 314        if (strcmp(type, commit_type)) {
 315                free(buffer);
 316                return error("Object %s not a commit",
 317                             sha1_to_hex(item->object.sha1));
 318        }
 319        ret = parse_commit_buffer(item, buffer, size);
 320        if (save_commit_buffer && !ret) {
 321                item->buffer = buffer;
 322                return 0;
 323        }
 324        free(buffer);
 325        return ret;
 326}
 327
 328struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
 329{
 330        struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
 331        new_list->item = item;
 332        new_list->next = *list_p;
 333        *list_p = new_list;
 334        return new_list;
 335}
 336
 337void free_commit_list(struct commit_list *list)
 338{
 339        while (list) {
 340                struct commit_list *temp = list;
 341                list = temp->next;
 342                free(temp);
 343        }
 344}
 345
 346struct commit_list * insert_by_date(struct commit *item, struct commit_list **list)
 347{
 348        struct commit_list **pp = list;
 349        struct commit_list *p;
 350        while ((p = *pp) != NULL) {
 351                if (p->item->date < item->date) {
 352                        break;
 353                }
 354                pp = &p->next;
 355        }
 356        return commit_list_insert(item, pp);
 357}
 358
 359        
 360void sort_by_date(struct commit_list **list)
 361{
 362        struct commit_list *ret = NULL;
 363        while (*list) {
 364                insert_by_date((*list)->item, &ret);
 365                *list = (*list)->next;
 366        }
 367        *list = ret;
 368}
 369
 370struct commit *pop_most_recent_commit(struct commit_list **list,
 371                                      unsigned int mark)
 372{
 373        struct commit *ret = (*list)->item;
 374        struct commit_list *parents = ret->parents;
 375        struct commit_list *old = *list;
 376
 377        *list = (*list)->next;
 378        free(old);
 379
 380        while (parents) {
 381                struct commit *commit = parents->item;
 382                parse_commit(commit);
 383                if (!(commit->object.flags & mark)) {
 384                        commit->object.flags |= mark;
 385                        insert_by_date(commit, list);
 386                }
 387                parents = parents->next;
 388        }
 389        return ret;
 390}
 391
 392void clear_commit_marks(struct commit *commit, unsigned int mark)
 393{
 394        struct commit_list *parents;
 395
 396        parents = commit->parents;
 397        commit->object.flags &= ~mark;
 398        while (parents) {
 399                struct commit *parent = parents->item;
 400                if (parent && parent->object.parsed &&
 401                    (parent->object.flags & mark))
 402                        clear_commit_marks(parent, mark);
 403                parents = parents->next;
 404        }
 405}
 406
 407/*
 408 * Generic support for pretty-printing the header
 409 */
 410static int get_one_line(const char *msg, unsigned long len)
 411{
 412        int ret = 0;
 413
 414        while (len--) {
 415                char c = *msg++;
 416                if (!c)
 417                        break;
 418                ret++;
 419                if (c == '\n')
 420                        break;
 421        }
 422        return ret;
 423}
 424
 425static int add_user_info(const char *what, enum cmit_fmt fmt, char *buf, const char *line)
 426{
 427        char *date;
 428        int namelen;
 429        unsigned long time;
 430        int tz, ret;
 431        const char *filler = "    ";
 432
 433        if (fmt == CMIT_FMT_ONELINE)
 434                return 0;
 435        date = strchr(line, '>');
 436        if (!date)
 437                return 0;
 438        namelen = ++date - line;
 439        time = strtoul(date, &date, 10);
 440        tz = strtol(date, NULL, 10);
 441
 442        if (fmt == CMIT_FMT_EMAIL) {
 443                what = "From";
 444                filler = "";
 445        }
 446        ret = sprintf(buf, "%s: %.*s%.*s\n", what,
 447                      (fmt == CMIT_FMT_FULLER) ? 4 : 0,
 448                      filler, namelen, line);
 449        switch (fmt) {
 450        case CMIT_FMT_MEDIUM:
 451                ret += sprintf(buf + ret, "Date:   %s\n", show_date(time, tz));
 452                break;
 453        case CMIT_FMT_EMAIL:
 454                ret += sprintf(buf + ret, "Date: %s\n",
 455                               show_rfc2822_date(time, tz));
 456                break;
 457        case CMIT_FMT_FULLER:
 458                ret += sprintf(buf + ret, "%sDate: %s\n", what, show_date(time, tz));
 459                break;
 460        default:
 461                /* notin' */
 462                break;
 463        }
 464        return ret;
 465}
 466
 467static int is_empty_line(const char *line, int *len_p)
 468{
 469        int len = *len_p;
 470        while (len && isspace(line[len-1]))
 471                len--;
 472        *len_p = len;
 473        return !len;
 474}
 475
 476static int add_merge_info(enum cmit_fmt fmt, char *buf, const struct commit *commit, int abbrev)
 477{
 478        struct commit_list *parent = commit->parents;
 479        int offset;
 480
 481        if ((fmt == CMIT_FMT_ONELINE) || (fmt == CMIT_FMT_EMAIL) ||
 482            !parent || !parent->next)
 483                return 0;
 484
 485        offset = sprintf(buf, "Merge:");
 486
 487        while (parent) {
 488                struct commit *p = parent->item;
 489                const char *hex = abbrev
 490                        ? find_unique_abbrev(p->object.sha1, abbrev)
 491                        : sha1_to_hex(p->object.sha1);
 492                char *dots = (abbrev && strlen(hex) != 40) ? "..." : "";
 493                parent = parent->next;
 494
 495                offset += sprintf(buf + offset, " %s%s", hex, dots);
 496        }
 497        buf[offset++] = '\n';
 498        return offset;
 499}
 500
 501unsigned long pretty_print_commit(enum cmit_fmt fmt, const struct commit *commit, unsigned long len, char *buf, unsigned long space, int abbrev, const char *subject)
 502{
 503        int hdr = 1, body = 0;
 504        unsigned long offset = 0;
 505        int indent = 4;
 506        int parents_shown = 0;
 507        const char *msg = commit->buffer;
 508
 509        if (fmt == CMIT_FMT_ONELINE || fmt == CMIT_FMT_EMAIL)
 510                indent = 0;
 511
 512        for (;;) {
 513                const char *line = msg;
 514                int linelen = get_one_line(msg, len);
 515
 516                if (!linelen)
 517                        break;
 518
 519                /*
 520                 * We want some slop for indentation and a possible
 521                 * final "...". Thus the "+ 20".
 522                 */
 523                if (offset + linelen + 20 > space) {
 524                        memcpy(buf + offset, "    ...\n", 8);
 525                        offset += 8;
 526                        break;
 527                }
 528
 529                msg += linelen;
 530                len -= linelen;
 531                if (hdr) {
 532                        if (linelen == 1) {
 533                                hdr = 0;
 534                                if ((fmt != CMIT_FMT_ONELINE) && !subject)
 535                                        buf[offset++] = '\n';
 536                                continue;
 537                        }
 538                        if (fmt == CMIT_FMT_RAW) {
 539                                memcpy(buf + offset, line, linelen);
 540                                offset += linelen;
 541                                continue;
 542                        }
 543                        if (!memcmp(line, "parent ", 7)) {
 544                                if (linelen != 48)
 545                                        die("bad parent line in commit");
 546                                continue;
 547                        }
 548
 549                        if (!parents_shown) {
 550                                offset += add_merge_info(fmt, buf + offset,
 551                                                         commit, abbrev);
 552                                parents_shown = 1;
 553                                continue;
 554                        }
 555                        /*
 556                         * MEDIUM == DEFAULT shows only author with dates.
 557                         * FULL shows both authors but not dates.
 558                         * FULLER shows both authors and dates.
 559                         */
 560                        if (!memcmp(line, "author ", 7))
 561                                offset += add_user_info("Author", fmt,
 562                                                        buf + offset,
 563                                                        line + 7);
 564                        if (!memcmp(line, "committer ", 10) &&
 565                            (fmt == CMIT_FMT_FULL || fmt == CMIT_FMT_FULLER))
 566                                offset += add_user_info("Commit", fmt,
 567                                                        buf + offset,
 568                                                        line + 10);
 569                        continue;
 570                }
 571
 572                if (is_empty_line(line, &linelen)) {
 573                        if (!body)
 574                                continue;
 575                        if (subject)
 576                                continue;
 577                        if (fmt == CMIT_FMT_SHORT)
 578                                break;
 579                } else {
 580                        body = 1;
 581                }
 582
 583                if (subject) {
 584                        int slen = strlen(subject);
 585                        memcpy(buf + offset, subject, slen);
 586                        offset += slen;
 587                }
 588                memset(buf + offset, ' ', indent);
 589                memcpy(buf + offset + indent, line, linelen);
 590                offset += linelen + indent;
 591                buf[offset++] = '\n';
 592                if (fmt == CMIT_FMT_ONELINE)
 593                        break;
 594                subject = NULL;
 595        }
 596        while (offset && isspace(buf[offset-1]))
 597                offset--;
 598        /* Make sure there is an EOLN for the non-oneline case */
 599        if (fmt != CMIT_FMT_ONELINE)
 600                buf[offset++] = '\n';
 601        buf[offset] = '\0';
 602        return offset;
 603}
 604
 605struct commit *pop_commit(struct commit_list **stack)
 606{
 607        struct commit_list *top = *stack;
 608        struct commit *item = top ? top->item : NULL;
 609
 610        if (top) {
 611                *stack = top->next;
 612                free(top);
 613        }
 614        return item;
 615}
 616
 617int count_parents(struct commit * commit)
 618{
 619        int count = 0;
 620        struct commit_list * parents = commit->parents;
 621        for (count=0;parents; parents=parents->next,count++)
 622          ;
 623        return count;
 624}
 625
 626void topo_sort_default_setter(struct commit *c, void *data)
 627{
 628        c->object.util = data;
 629}
 630
 631void *topo_sort_default_getter(struct commit *c)
 632{
 633        return c->object.util;
 634}
 635
 636/*
 637 * Performs an in-place topological sort on the list supplied.
 638 */
 639void sort_in_topological_order(struct commit_list ** list, int lifo)
 640{
 641        sort_in_topological_order_fn(list, lifo, topo_sort_default_setter,
 642                                     topo_sort_default_getter);
 643}
 644
 645void sort_in_topological_order_fn(struct commit_list ** list, int lifo,
 646                                  topo_sort_set_fn_t setter,
 647                                  topo_sort_get_fn_t getter)
 648{
 649        struct commit_list * next = *list;
 650        struct commit_list * work = NULL, **insert;
 651        struct commit_list ** pptr = list;
 652        struct sort_node * nodes;
 653        struct sort_node * next_nodes;
 654        int count = 0;
 655
 656        /* determine the size of the list */
 657        while (next) {
 658                next = next->next;
 659                count++;
 660        }
 661        
 662        if (!count)
 663                return;
 664        /* allocate an array to help sort the list */
 665        nodes = xcalloc(count, sizeof(*nodes));
 666        /* link the list to the array */
 667        next_nodes = nodes;
 668        next=*list;
 669        while (next) {
 670                next_nodes->list_item = next;
 671                setter(next->item, next_nodes);
 672                next_nodes++;
 673                next = next->next;
 674        }
 675        /* update the indegree */
 676        next=*list;
 677        while (next) {
 678                struct commit_list * parents = next->item->parents;
 679                while (parents) {
 680                        struct commit * parent=parents->item;
 681                        struct sort_node * pn = (struct sort_node *) getter(parent);
 682
 683                        if (pn)
 684                                pn->indegree++;
 685                        parents=parents->next;
 686                }
 687                next=next->next;
 688        }
 689        /* 
 690         * find the tips
 691         *
 692         * tips are nodes not reachable from any other node in the list 
 693         * 
 694         * the tips serve as a starting set for the work queue.
 695         */
 696        next=*list;
 697        insert = &work;
 698        while (next) {
 699                struct sort_node * node = (struct sort_node *) getter(next->item);
 700
 701                if (node->indegree == 0) {
 702                        insert = &commit_list_insert(next->item, insert)->next;
 703                }
 704                next=next->next;
 705        }
 706
 707        /* process the list in topological order */
 708        if (!lifo)
 709                sort_by_date(&work);
 710        while (work) {
 711                struct commit * work_item = pop_commit(&work);
 712                struct sort_node * work_node = (struct sort_node *) getter(work_item);
 713                struct commit_list * parents = work_item->parents;
 714
 715                while (parents) {
 716                        struct commit * parent=parents->item;
 717                        struct sort_node * pn = (struct sort_node *) getter(parent);
 718
 719                        if (pn) {
 720                                /*
 721                                 * parents are only enqueued for emission 
 722                                 * when all their children have been emitted thereby
 723                                 * guaranteeing topological order.
 724                                 */
 725                                pn->indegree--;
 726                                if (!pn->indegree) {
 727                                        if (!lifo)
 728                                                insert_by_date(parent, &work);
 729                                        else
 730                                                commit_list_insert(parent, &work);
 731                                }
 732                        }
 733                        parents=parents->next;
 734                }
 735                /*
 736                 * work_item is a commit all of whose children
 737                 * have already been emitted. we can emit it now.
 738                 */
 739                *pptr = work_node->list_item;
 740                pptr = &(*pptr)->next;
 741                *pptr = NULL;
 742                setter(work_item, NULL);
 743        }
 744        free(nodes);
 745}