Andrew's git / gitweb.git / commit.c
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commit.con commit fix repack with --max-pack-size (5476a8a)
   1#include "cache.h"
   2#include "tag.h"
   3#include "commit.h"
   4#include "pkt-line.h"
   5#include "utf8.h"
   6#include "interpolate.h"
   7#include "diff.h"
   8#include "revision.h"
   9
  10int save_commit_buffer = 1;
  11
  12struct sort_node
  13{
  14        /*
  15         * the number of children of the associated commit
  16         * that also occur in the list being sorted.
  17         */
  18        unsigned int indegree;
  19
  20        /*
  21         * reference to original list item that we will re-use
  22         * on output.
  23         */
  24        struct commit_list * list_item;
  25
  26};
  27
  28const char *commit_type = "commit";
  29
  30struct cmt_fmt_map {
  31        const char *n;
  32        size_t cmp_len;
  33        enum cmit_fmt v;
  34} cmt_fmts[] = {
  35        { "raw",        1,      CMIT_FMT_RAW },
  36        { "medium",     1,      CMIT_FMT_MEDIUM },
  37        { "short",      1,      CMIT_FMT_SHORT },
  38        { "email",      1,      CMIT_FMT_EMAIL },
  39        { "full",       5,      CMIT_FMT_FULL },
  40        { "fuller",     5,      CMIT_FMT_FULLER },
  41        { "oneline",    1,      CMIT_FMT_ONELINE },
  42        { "format:",    7,      CMIT_FMT_USERFORMAT},
  43};
  44
  45static char *user_format;
  46
  47enum cmit_fmt get_commit_format(const char *arg)
  48{
  49        int i;
  50
  51        if (!arg || !*arg)
  52                return CMIT_FMT_DEFAULT;
  53        if (*arg == '=')
  54                arg++;
  55        if (!prefixcmp(arg, "format:")) {
  56                if (user_format)
  57                        free(user_format);
  58                user_format = xstrdup(arg + 7);
  59                return CMIT_FMT_USERFORMAT;
  60        }
  61        for (i = 0; i < ARRAY_SIZE(cmt_fmts); i++) {
  62                if (!strncmp(arg, cmt_fmts[i].n, cmt_fmts[i].cmp_len) &&
  63                    !strncmp(arg, cmt_fmts[i].n, strlen(arg)))
  64                        return cmt_fmts[i].v;
  65        }
  66
  67        die("invalid --pretty format: %s", arg);
  68}
  69
  70static struct commit *check_commit(struct object *obj,
  71                                   const unsigned char *sha1,
  72                                   int quiet)
  73{
  74        if (obj->type != OBJ_COMMIT) {
  75                if (!quiet)
  76                        error("Object %s is a %s, not a commit",
  77                              sha1_to_hex(sha1), typename(obj->type));
  78                return NULL;
  79        }
  80        return (struct commit *) obj;
  81}
  82
  83struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
  84                                              int quiet)
  85{
  86        struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
  87
  88        if (!obj)
  89                return NULL;
  90        return check_commit(obj, sha1, quiet);
  91}
  92
  93struct commit *lookup_commit_reference(const unsigned char *sha1)
  94{
  95        return lookup_commit_reference_gently(sha1, 0);
  96}
  97
  98struct commit *lookup_commit(const unsigned char *sha1)
  99{
 100        struct object *obj = lookup_object(sha1);
 101        if (!obj)
 102                return create_object(sha1, OBJ_COMMIT, alloc_commit_node());
 103        if (!obj->type)
 104                obj->type = OBJ_COMMIT;
 105        return check_commit(obj, sha1, 0);
 106}
 107
 108static unsigned long parse_commit_date(const char *buf)
 109{
 110        unsigned long date;
 111
 112        if (memcmp(buf, "author", 6))
 113                return 0;
 114        while (*buf++ != '\n')
 115                /* nada */;
 116        if (memcmp(buf, "committer", 9))
 117                return 0;
 118        while (*buf++ != '>')
 119                /* nada */;
 120        date = strtoul(buf, NULL, 10);
 121        if (date == ULONG_MAX)
 122                date = 0;
 123        return date;
 124}
 125
 126static struct commit_graft **commit_graft;
 127static int commit_graft_alloc, commit_graft_nr;
 128
 129static int commit_graft_pos(const unsigned char *sha1)
 130{
 131        int lo, hi;
 132        lo = 0;
 133        hi = commit_graft_nr;
 134        while (lo < hi) {
 135                int mi = (lo + hi) / 2;
 136                struct commit_graft *graft = commit_graft[mi];
 137                int cmp = hashcmp(sha1, graft->sha1);
 138                if (!cmp)
 139                        return mi;
 140                if (cmp < 0)
 141                        hi = mi;
 142                else
 143                        lo = mi + 1;
 144        }
 145        return -lo - 1;
 146}
 147
 148int register_commit_graft(struct commit_graft *graft, int ignore_dups)
 149{
 150        int pos = commit_graft_pos(graft->sha1);
 151        
 152        if (0 <= pos) {
 153                if (ignore_dups)
 154                        free(graft);
 155                else {
 156                        free(commit_graft[pos]);
 157                        commit_graft[pos] = graft;
 158                }
 159                return 1;
 160        }
 161        pos = -pos - 1;
 162        if (commit_graft_alloc <= ++commit_graft_nr) {
 163                commit_graft_alloc = alloc_nr(commit_graft_alloc);
 164                commit_graft = xrealloc(commit_graft,
 165                                        sizeof(*commit_graft) *
 166                                        commit_graft_alloc);
 167        }
 168        if (pos < commit_graft_nr)
 169                memmove(commit_graft + pos + 1,
 170                        commit_graft + pos,
 171                        (commit_graft_nr - pos - 1) *
 172                        sizeof(*commit_graft));
 173        commit_graft[pos] = graft;
 174        return 0;
 175}
 176
 177struct commit_graft *read_graft_line(char *buf, int len)
 178{
 179        /* The format is just "Commit Parent1 Parent2 ...\n" */
 180        int i;
 181        struct commit_graft *graft = NULL;
 182
 183        if (buf[len-1] == '\n')
 184                buf[--len] = 0;
 185        if (buf[0] == '#' || buf[0] == '\0')
 186                return NULL;
 187        if ((len + 1) % 41) {
 188        bad_graft_data:
 189                error("bad graft data: %s", buf);
 190                free(graft);
 191                return NULL;
 192        }
 193        i = (len + 1) / 41 - 1;
 194        graft = xmalloc(sizeof(*graft) + 20 * i);
 195        graft->nr_parent = i;
 196        if (get_sha1_hex(buf, graft->sha1))
 197                goto bad_graft_data;
 198        for (i = 40; i < len; i += 41) {
 199                if (buf[i] != ' ')
 200                        goto bad_graft_data;
 201                if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
 202                        goto bad_graft_data;
 203        }
 204        return graft;
 205}
 206
 207int read_graft_file(const char *graft_file)
 208{
 209        FILE *fp = fopen(graft_file, "r");
 210        char buf[1024];
 211        if (!fp)
 212                return -1;
 213        while (fgets(buf, sizeof(buf), fp)) {
 214                /* The format is just "Commit Parent1 Parent2 ...\n" */
 215                int len = strlen(buf);
 216                struct commit_graft *graft = read_graft_line(buf, len);
 217                if (!graft)
 218                        continue;
 219                if (register_commit_graft(graft, 1))
 220                        error("duplicate graft data: %s", buf);
 221        }
 222        fclose(fp);
 223        return 0;
 224}
 225
 226static void prepare_commit_graft(void)
 227{
 228        static int commit_graft_prepared;
 229        char *graft_file;
 230
 231        if (commit_graft_prepared)
 232                return;
 233        graft_file = get_graft_file();
 234        read_graft_file(graft_file);
 235        /* make sure shallows are read */
 236        is_repository_shallow();
 237        commit_graft_prepared = 1;
 238}
 239
 240static struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
 241{
 242        int pos;
 243        prepare_commit_graft();
 244        pos = commit_graft_pos(sha1);
 245        if (pos < 0)
 246                return NULL;
 247        return commit_graft[pos];
 248}
 249
 250int write_shallow_commits(int fd, int use_pack_protocol)
 251{
 252        int i, count = 0;
 253        for (i = 0; i < commit_graft_nr; i++)
 254                if (commit_graft[i]->nr_parent < 0) {
 255                        const char *hex =
 256                                sha1_to_hex(commit_graft[i]->sha1);
 257                        count++;
 258                        if (use_pack_protocol)
 259                                packet_write(fd, "shallow %s", hex);
 260                        else {
 261                                if (write_in_full(fd, hex,  40) != 40)
 262                                        break;
 263                                if (write_in_full(fd, "\n", 1) != 1)
 264                                        break;
 265                        }
 266                }
 267        return count;
 268}
 269
 270int unregister_shallow(const unsigned char *sha1)
 271{
 272        int pos = commit_graft_pos(sha1);
 273        if (pos < 0)
 274                return -1;
 275        if (pos + 1 < commit_graft_nr)
 276                memcpy(commit_graft + pos, commit_graft + pos + 1,
 277                                sizeof(struct commit_graft *)
 278                                * (commit_graft_nr - pos - 1));
 279        commit_graft_nr--;
 280        return 0;
 281}
 282
 283int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
 284{
 285        char *tail = buffer;
 286        char *bufptr = buffer;
 287        unsigned char parent[20];
 288        struct commit_list **pptr;
 289        struct commit_graft *graft;
 290        unsigned n_refs = 0;
 291
 292        if (item->object.parsed)
 293                return 0;
 294        item->object.parsed = 1;
 295        tail += size;
 296        if (tail <= bufptr + 5 || memcmp(bufptr, "tree ", 5))
 297                return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
 298        if (tail <= bufptr + 45 || get_sha1_hex(bufptr + 5, parent) < 0)
 299                return error("bad tree pointer in commit %s",
 300                             sha1_to_hex(item->object.sha1));
 301        item->tree = lookup_tree(parent);
 302        if (item->tree)
 303                n_refs++;
 304        bufptr += 46; /* "tree " + "hex sha1" + "\n" */
 305        pptr = &item->parents;
 306
 307        graft = lookup_commit_graft(item->object.sha1);
 308        while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
 309                struct commit *new_parent;
 310
 311                if (tail <= bufptr + 48 ||
 312                    get_sha1_hex(bufptr + 7, parent) ||
 313                    bufptr[47] != '\n')
 314                        return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
 315                bufptr += 48;
 316                if (graft)
 317                        continue;
 318                new_parent = lookup_commit(parent);
 319                if (new_parent) {
 320                        pptr = &commit_list_insert(new_parent, pptr)->next;
 321                        n_refs++;
 322                }
 323        }
 324        if (graft) {
 325                int i;
 326                struct commit *new_parent;
 327                for (i = 0; i < graft->nr_parent; i++) {
 328                        new_parent = lookup_commit(graft->parent[i]);
 329                        if (!new_parent)
 330                                continue;
 331                        pptr = &commit_list_insert(new_parent, pptr)->next;
 332                        n_refs++;
 333                }
 334        }
 335        item->date = parse_commit_date(bufptr);
 336
 337        if (track_object_refs) {
 338                unsigned i = 0;
 339                struct commit_list *p;
 340                struct object_refs *refs = alloc_object_refs(n_refs);
 341                if (item->tree)
 342                        refs->ref[i++] = &item->tree->object;
 343                for (p = item->parents; p; p = p->next)
 344                        refs->ref[i++] = &p->item->object;
 345                set_object_refs(&item->object, refs);
 346        }
 347
 348        return 0;
 349}
 350
 351int parse_commit(struct commit *item)
 352{
 353        enum object_type type;
 354        void *buffer;
 355        unsigned long size;
 356        int ret;
 357
 358        if (item->object.parsed)
 359                return 0;
 360        buffer = read_sha1_file(item->object.sha1, &type, &size);
 361        if (!buffer)
 362                return error("Could not read %s",
 363                             sha1_to_hex(item->object.sha1));
 364        if (type != OBJ_COMMIT) {
 365                free(buffer);
 366                return error("Object %s not a commit",
 367                             sha1_to_hex(item->object.sha1));
 368        }
 369        ret = parse_commit_buffer(item, buffer, size);
 370        if (save_commit_buffer && !ret) {
 371                item->buffer = buffer;
 372                return 0;
 373        }
 374        free(buffer);
 375        return ret;
 376}
 377
 378struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
 379{
 380        struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
 381        new_list->item = item;
 382        new_list->next = *list_p;
 383        *list_p = new_list;
 384        return new_list;
 385}
 386
 387void free_commit_list(struct commit_list *list)
 388{
 389        while (list) {
 390                struct commit_list *temp = list;
 391                list = temp->next;
 392                free(temp);
 393        }
 394}
 395
 396struct commit_list * insert_by_date(struct commit *item, struct commit_list **list)
 397{
 398        struct commit_list **pp = list;
 399        struct commit_list *p;
 400        while ((p = *pp) != NULL) {
 401                if (p->item->date < item->date) {
 402                        break;
 403                }
 404                pp = &p->next;
 405        }
 406        return commit_list_insert(item, pp);
 407}
 408
 409        
 410void sort_by_date(struct commit_list **list)
 411{
 412        struct commit_list *ret = NULL;
 413        while (*list) {
 414                insert_by_date((*list)->item, &ret);
 415                *list = (*list)->next;
 416        }
 417        *list = ret;
 418}
 419
 420struct commit *pop_most_recent_commit(struct commit_list **list,
 421                                      unsigned int mark)
 422{
 423        struct commit *ret = (*list)->item;
 424        struct commit_list *parents = ret->parents;
 425        struct commit_list *old = *list;
 426
 427        *list = (*list)->next;
 428        free(old);
 429
 430        while (parents) {
 431                struct commit *commit = parents->item;
 432                parse_commit(commit);
 433                if (!(commit->object.flags & mark)) {
 434                        commit->object.flags |= mark;
 435                        insert_by_date(commit, list);
 436                }
 437                parents = parents->next;
 438        }
 439        return ret;
 440}
 441
 442void clear_commit_marks(struct commit *commit, unsigned int mark)
 443{
 444        struct commit_list *parents;
 445
 446        commit->object.flags &= ~mark;
 447        parents = commit->parents;
 448        while (parents) {
 449                struct commit *parent = parents->item;
 450
 451                /* Have we already cleared this? */
 452                if (mark & parent->object.flags)
 453                        clear_commit_marks(parent, mark);
 454                parents = parents->next;
 455        }
 456}
 457
 458/*
 459 * Generic support for pretty-printing the header
 460 */
 461static int get_one_line(const char *msg, unsigned long len)
 462{
 463        int ret = 0;
 464
 465        while (len--) {
 466                char c = *msg++;
 467                if (!c)
 468                        break;
 469                ret++;
 470                if (c == '\n')
 471                        break;
 472        }
 473        return ret;
 474}
 475
 476/* High bit set, or ISO-2022-INT */
 477static int non_ascii(int ch)
 478{
 479        ch = (ch & 0xff);
 480        return ((ch & 0x80) || (ch == 0x1b));
 481}
 482
 483static int is_rfc2047_special(char ch)
 484{
 485        return (non_ascii(ch) || (ch == '=') || (ch == '?') || (ch == '_'));
 486}
 487
 488static int add_rfc2047(char *buf, const char *line, int len,
 489                       const char *encoding)
 490{
 491        char *bp = buf;
 492        int i, needquote;
 493        char q_encoding[128];
 494        const char *q_encoding_fmt = "=?%s?q?";
 495
 496        for (i = needquote = 0; !needquote && i < len; i++) {
 497                int ch = line[i];
 498                if (non_ascii(ch))
 499                        needquote++;
 500                if ((i + 1 < len) &&
 501                    (ch == '=' && line[i+1] == '?'))
 502                        needquote++;
 503        }
 504        if (!needquote)
 505                return sprintf(buf, "%.*s", len, line);
 506
 507        i = snprintf(q_encoding, sizeof(q_encoding), q_encoding_fmt, encoding);
 508        if (sizeof(q_encoding) < i)
 509                die("Insanely long encoding name %s", encoding);
 510        memcpy(bp, q_encoding, i);
 511        bp += i;
 512        for (i = 0; i < len; i++) {
 513                unsigned ch = line[i] & 0xFF;
 514                if (is_rfc2047_special(ch)) {
 515                        sprintf(bp, "=%02X", ch);
 516                        bp += 3;
 517                }
 518                else if (ch == ' ')
 519                        *bp++ = '_';
 520                else
 521                        *bp++ = ch;
 522        }
 523        memcpy(bp, "?=", 2);
 524        bp += 2;
 525        return bp - buf;
 526}
 527
 528static int add_user_info(const char *what, enum cmit_fmt fmt, char *buf,
 529                         const char *line, enum date_mode dmode,
 530                         const char *encoding)
 531{
 532        char *date;
 533        int namelen;
 534        unsigned long time;
 535        int tz, ret;
 536        const char *filler = "    ";
 537
 538        if (fmt == CMIT_FMT_ONELINE)
 539                return 0;
 540        date = strchr(line, '>');
 541        if (!date)
 542                return 0;
 543        namelen = ++date - line;
 544        time = strtoul(date, &date, 10);
 545        tz = strtol(date, NULL, 10);
 546
 547        if (fmt == CMIT_FMT_EMAIL) {
 548                char *name_tail = strchr(line, '<');
 549                int display_name_length;
 550                if (!name_tail)
 551                        return 0;
 552                while (line < name_tail && isspace(name_tail[-1]))
 553                        name_tail--;
 554                display_name_length = name_tail - line;
 555                filler = "";
 556                strcpy(buf, "From: ");
 557                ret = strlen(buf);
 558                ret += add_rfc2047(buf + ret, line, display_name_length,
 559                                   encoding);
 560                memcpy(buf + ret, name_tail, namelen - display_name_length);
 561                ret += namelen - display_name_length;
 562                buf[ret++] = '\n';
 563        }
 564        else {
 565                ret = sprintf(buf, "%s: %.*s%.*s\n", what,
 566                              (fmt == CMIT_FMT_FULLER) ? 4 : 0,
 567                              filler, namelen, line);
 568        }
 569        switch (fmt) {
 570        case CMIT_FMT_MEDIUM:
 571                ret += sprintf(buf + ret, "Date:   %s\n",
 572                               show_date(time, tz, dmode));
 573                break;
 574        case CMIT_FMT_EMAIL:
 575                ret += sprintf(buf + ret, "Date: %s\n",
 576                               show_rfc2822_date(time, tz));
 577                break;
 578        case CMIT_FMT_FULLER:
 579                ret += sprintf(buf + ret, "%sDate: %s\n", what,
 580                               show_date(time, tz, dmode));
 581                break;
 582        default:
 583                /* notin' */
 584                break;
 585        }
 586        return ret;
 587}
 588
 589static int is_empty_line(const char *line, int *len_p)
 590{
 591        int len = *len_p;
 592        while (len && isspace(line[len-1]))
 593                len--;
 594        *len_p = len;
 595        return !len;
 596}
 597
 598static int add_merge_info(enum cmit_fmt fmt, char *buf, const struct commit *commit, int abbrev)
 599{
 600        struct commit_list *parent = commit->parents;
 601        int offset;
 602
 603        if ((fmt == CMIT_FMT_ONELINE) || (fmt == CMIT_FMT_EMAIL) ||
 604            !parent || !parent->next)
 605                return 0;
 606
 607        offset = sprintf(buf, "Merge:");
 608
 609        while (parent) {
 610                struct commit *p = parent->item;
 611                const char *hex = NULL;
 612                const char *dots;
 613                if (abbrev)
 614                        hex = find_unique_abbrev(p->object.sha1, abbrev);
 615                if (!hex)
 616                        hex = sha1_to_hex(p->object.sha1);
 617                dots = (abbrev && strlen(hex) != 40) ?  "..." : "";
 618                parent = parent->next;
 619
 620                offset += sprintf(buf + offset, " %s%s", hex, dots);
 621        }
 622        buf[offset++] = '\n';
 623        return offset;
 624}
 625
 626static char *get_header(const struct commit *commit, const char *key)
 627{
 628        int key_len = strlen(key);
 629        const char *line = commit->buffer;
 630
 631        for (;;) {
 632                const char *eol = strchr(line, '\n'), *next;
 633
 634                if (line == eol)
 635                        return NULL;
 636                if (!eol) {
 637                        eol = line + strlen(line);
 638                        next = NULL;
 639                } else
 640                        next = eol + 1;
 641                if (eol - line > key_len &&
 642                    !strncmp(line, key, key_len) &&
 643                    line[key_len] == ' ') {
 644                        int len = eol - line - key_len;
 645                        char *ret = xmalloc(len);
 646                        memcpy(ret, line + key_len + 1, len - 1);
 647                        ret[len - 1] = '\0';
 648                        return ret;
 649                }
 650                line = next;
 651        }
 652}
 653
 654static char *replace_encoding_header(char *buf, const char *encoding)
 655{
 656        char *encoding_header = strstr(buf, "\nencoding ");
 657        char *header_end = strstr(buf, "\n\n");
 658        char *end_of_encoding_header;
 659        int encoding_header_pos;
 660        int encoding_header_len;
 661        int new_len;
 662        int need_len;
 663        int buflen = strlen(buf) + 1;
 664
 665        if (!header_end)
 666                header_end = buf + buflen;
 667        if (!encoding_header || encoding_header >= header_end)
 668                return buf;
 669        encoding_header++;
 670        end_of_encoding_header = strchr(encoding_header, '\n');
 671        if (!end_of_encoding_header)
 672                return buf; /* should not happen but be defensive */
 673        end_of_encoding_header++;
 674
 675        encoding_header_len = end_of_encoding_header - encoding_header;
 676        encoding_header_pos = encoding_header - buf;
 677
 678        if (is_encoding_utf8(encoding)) {
 679                /* we have re-coded to UTF-8; drop the header */
 680                memmove(encoding_header, end_of_encoding_header,
 681                        buflen - (encoding_header_pos + encoding_header_len));
 682                return buf;
 683        }
 684        new_len = strlen(encoding);
 685        need_len = new_len + strlen("encoding \n");
 686        if (encoding_header_len < need_len) {
 687                buf = xrealloc(buf, buflen + (need_len - encoding_header_len));
 688                encoding_header = buf + encoding_header_pos;
 689                end_of_encoding_header = encoding_header + encoding_header_len;
 690        }
 691        memmove(end_of_encoding_header + (need_len - encoding_header_len),
 692                end_of_encoding_header,
 693                buflen - (encoding_header_pos + encoding_header_len));
 694        memcpy(encoding_header + 9, encoding, strlen(encoding));
 695        encoding_header[9 + new_len] = '\n';
 696        return buf;
 697}
 698
 699static char *logmsg_reencode(const struct commit *commit,
 700                             const char *output_encoding)
 701{
 702        static const char *utf8 = "utf-8";
 703        const char *use_encoding;
 704        char *encoding;
 705        char *out;
 706
 707        if (!*output_encoding)
 708                return NULL;
 709        encoding = get_header(commit, "encoding");
 710        use_encoding = encoding ? encoding : utf8;
 711        if (!strcmp(use_encoding, output_encoding))
 712                out = xstrdup(commit->buffer);
 713        else
 714                out = reencode_string(commit->buffer,
 715                                      output_encoding, use_encoding);
 716        if (out)
 717                out = replace_encoding_header(out, output_encoding);
 718
 719        free(encoding);
 720        return out;
 721}
 722
 723static void fill_person(struct interp *table, const char *msg, int len)
 724{
 725        int start, end, tz = 0;
 726        unsigned long date;
 727        char *ep;
 728
 729        /* parse name */
 730        for (end = 0; end < len && msg[end] != '<'; end++)
 731                ; /* do nothing */
 732        start = end + 1;
 733        while (end > 0 && isspace(msg[end - 1]))
 734                end--;
 735        table[0].value = xstrndup(msg, end);
 736
 737        if (start >= len)
 738                return;
 739
 740        /* parse email */
 741        for (end = start + 1; end < len && msg[end] != '>'; end++)
 742                ; /* do nothing */
 743
 744        if (end >= len)
 745                return;
 746
 747        table[1].value = xstrndup(msg + start, end - start);
 748
 749        /* parse date */
 750        for (start = end + 1; start < len && isspace(msg[start]); start++)
 751                ; /* do nothing */
 752        if (start >= len)
 753                return;
 754        date = strtoul(msg + start, &ep, 10);
 755        if (msg + start == ep)
 756                return;
 757
 758        table[5].value = xstrndup(msg + start, ep - (msg + start));
 759
 760        /* parse tz */
 761        for (start = ep - msg + 1; start < len && isspace(msg[start]); start++)
 762                ; /* do nothing */
 763        if (start + 1 < len) {
 764                tz = strtoul(msg + start + 1, NULL, 10);
 765                if (msg[start] == '-')
 766                        tz = -tz;
 767        }
 768
 769        interp_set_entry(table, 2, show_date(date, tz, 0));
 770        interp_set_entry(table, 3, show_rfc2822_date(date, tz));
 771        interp_set_entry(table, 4, show_date(date, tz, 1));
 772}
 773
 774static long format_commit_message(const struct commit *commit,
 775                const char *msg, char *buf, unsigned long space)
 776{
 777        struct interp table[] = {
 778                { "%H" },       /* commit hash */
 779                { "%h" },       /* abbreviated commit hash */
 780                { "%T" },       /* tree hash */
 781                { "%t" },       /* abbreviated tree hash */
 782                { "%P" },       /* parent hashes */
 783                { "%p" },       /* abbreviated parent hashes */
 784                { "%an" },      /* author name */
 785                { "%ae" },      /* author email */
 786                { "%ad" },      /* author date */
 787                { "%aD" },      /* author date, RFC2822 style */
 788                { "%ar" },      /* author date, relative */
 789                { "%at" },      /* author date, UNIX timestamp */
 790                { "%cn" },      /* committer name */
 791                { "%ce" },      /* committer email */
 792                { "%cd" },      /* committer date */
 793                { "%cD" },      /* committer date, RFC2822 style */
 794                { "%cr" },      /* committer date, relative */
 795                { "%ct" },      /* committer date, UNIX timestamp */
 796                { "%e" },       /* encoding */
 797                { "%s" },       /* subject */
 798                { "%b" },       /* body */
 799                { "%Cred" },    /* red */
 800                { "%Cgreen" },  /* green */
 801                { "%Cblue" },   /* blue */
 802                { "%Creset" },  /* reset color */
 803                { "%n" },       /* newline */
 804                { "%m" },       /* left/right/bottom */
 805        };
 806        enum interp_index {
 807                IHASH = 0, IHASH_ABBREV,
 808                ITREE, ITREE_ABBREV,
 809                IPARENTS, IPARENTS_ABBREV,
 810                IAUTHOR_NAME, IAUTHOR_EMAIL,
 811                IAUTHOR_DATE, IAUTHOR_DATE_RFC2822, IAUTHOR_DATE_RELATIVE,
 812                IAUTHOR_TIMESTAMP,
 813                ICOMMITTER_NAME, ICOMMITTER_EMAIL,
 814                ICOMMITTER_DATE, ICOMMITTER_DATE_RFC2822,
 815                ICOMMITTER_DATE_RELATIVE, ICOMMITTER_TIMESTAMP,
 816                IENCODING,
 817                ISUBJECT,
 818                IBODY,
 819                IRED, IGREEN, IBLUE, IRESET_COLOR,
 820                INEWLINE,
 821                ILEFT_RIGHT,
 822        };
 823        struct commit_list *p;
 824        char parents[1024];
 825        int i;
 826        enum { HEADER, SUBJECT, BODY } state;
 827
 828        if (ILEFT_RIGHT + 1 != ARRAY_SIZE(table))
 829                die("invalid interp table!");
 830
 831        /* these are independent of the commit */
 832        interp_set_entry(table, IRED, "\033[31m");
 833        interp_set_entry(table, IGREEN, "\033[32m");
 834        interp_set_entry(table, IBLUE, "\033[34m");
 835        interp_set_entry(table, IRESET_COLOR, "\033[m");
 836        interp_set_entry(table, INEWLINE, "\n");
 837
 838        /* these depend on the commit */
 839        if (!commit->object.parsed)
 840                parse_object(commit->object.sha1);
 841        interp_set_entry(table, IHASH, sha1_to_hex(commit->object.sha1));
 842        interp_set_entry(table, IHASH_ABBREV,
 843                        find_unique_abbrev(commit->object.sha1,
 844                                DEFAULT_ABBREV));
 845        interp_set_entry(table, ITREE, sha1_to_hex(commit->tree->object.sha1));
 846        interp_set_entry(table, ITREE_ABBREV,
 847                        find_unique_abbrev(commit->tree->object.sha1,
 848                                DEFAULT_ABBREV));
 849        interp_set_entry(table, ILEFT_RIGHT,
 850                         (commit->object.flags & BOUNDARY)
 851                         ? "-"
 852                         : (commit->object.flags & SYMMETRIC_LEFT)
 853                         ? "<"
 854                         : ">");
 855
 856        parents[1] = 0;
 857        for (i = 0, p = commit->parents;
 858                        p && i < sizeof(parents) - 1;
 859                        p = p->next)
 860                i += snprintf(parents + i, sizeof(parents) - i - 1, " %s",
 861                        sha1_to_hex(p->item->object.sha1));
 862        interp_set_entry(table, IPARENTS, parents + 1);
 863
 864        parents[1] = 0;
 865        for (i = 0, p = commit->parents;
 866                        p && i < sizeof(parents) - 1;
 867                        p = p->next)
 868                i += snprintf(parents + i, sizeof(parents) - i - 1, " %s",
 869                        find_unique_abbrev(p->item->object.sha1,
 870                                DEFAULT_ABBREV));
 871        interp_set_entry(table, IPARENTS_ABBREV, parents + 1);
 872
 873        for (i = 0, state = HEADER; msg[i] && state < BODY; i++) {
 874                int eol;
 875                for (eol = i; msg[eol] && msg[eol] != '\n'; eol++)
 876                        ; /* do nothing */
 877
 878                if (state == SUBJECT) {
 879                        table[ISUBJECT].value = xstrndup(msg + i, eol - i);
 880                        i = eol;
 881                }
 882                if (i == eol) {
 883                        state++;
 884                        /* strip empty lines */
 885                        while (msg[eol + 1] == '\n')
 886                                eol++;
 887                } else if (!prefixcmp(msg + i, "author "))
 888                        fill_person(table + IAUTHOR_NAME,
 889                                        msg + i + 7, eol - i - 7);
 890                else if (!prefixcmp(msg + i, "committer "))
 891                        fill_person(table + ICOMMITTER_NAME,
 892                                        msg + i + 10, eol - i - 10);
 893                else if (!prefixcmp(msg + i, "encoding "))
 894                        table[IENCODING].value =
 895                                xstrndup(msg + i + 9, eol - i - 9);
 896                i = eol;
 897        }
 898        if (msg[i])
 899                table[IBODY].value = xstrdup(msg + i);
 900        for (i = 0; i < ARRAY_SIZE(table); i++)
 901                if (!table[i].value)
 902                        interp_set_entry(table, i, "<unknown>");
 903
 904        interpolate(buf, space, user_format, table, ARRAY_SIZE(table));
 905        interp_clear_table(table, ARRAY_SIZE(table));
 906
 907        return strlen(buf);
 908}
 909
 910unsigned long pretty_print_commit(enum cmit_fmt fmt,
 911                                  const struct commit *commit,
 912                                  unsigned long len,
 913                                  char *buf, unsigned long space,
 914                                  int abbrev, const char *subject,
 915                                  const char *after_subject,
 916                                  enum date_mode dmode)
 917{
 918        int hdr = 1, body = 0, seen_title = 0;
 919        unsigned long offset = 0;
 920        int indent = 4;
 921        int parents_shown = 0;
 922        const char *msg = commit->buffer;
 923        int plain_non_ascii = 0;
 924        char *reencoded;
 925        const char *encoding;
 926
 927        if (fmt == CMIT_FMT_USERFORMAT)
 928                return format_commit_message(commit, msg, buf, space);
 929
 930        encoding = (git_log_output_encoding
 931                    ? git_log_output_encoding
 932                    : git_commit_encoding);
 933        if (!encoding)
 934                encoding = "utf-8";
 935        reencoded = logmsg_reencode(commit, encoding);
 936        if (reencoded)
 937                msg = reencoded;
 938
 939        if (fmt == CMIT_FMT_ONELINE || fmt == CMIT_FMT_EMAIL)
 940                indent = 0;
 941
 942        /* After-subject is used to pass in Content-Type: multipart
 943         * MIME header; in that case we do not have to do the
 944         * plaintext content type even if the commit message has
 945         * non 7-bit ASCII character.  Otherwise, check if we need
 946         * to say this is not a 7-bit ASCII.
 947         */
 948        if (fmt == CMIT_FMT_EMAIL && !after_subject) {
 949                int i, ch, in_body;
 950
 951                for (in_body = i = 0; (ch = msg[i]) && i < len; i++) {
 952                        if (!in_body) {
 953                                /* author could be non 7-bit ASCII but
 954                                 * the log may be so; skip over the
 955                                 * header part first.
 956                                 */
 957                                if (ch == '\n' &&
 958                                    i + 1 < len && msg[i+1] == '\n')
 959                                        in_body = 1;
 960                        }
 961                        else if (non_ascii(ch)) {
 962                                plain_non_ascii = 1;
 963                                break;
 964                        }
 965                }
 966        }
 967
 968        for (;;) {
 969                const char *line = msg;
 970                int linelen = get_one_line(msg, len);
 971
 972                if (!linelen)
 973                        break;
 974
 975                /*
 976                 * We want some slop for indentation and a possible
 977                 * final "...". Thus the "+ 20".
 978                 */
 979                if (offset + linelen + 20 > space) {
 980                        memcpy(buf + offset, "    ...\n", 8);
 981                        offset += 8;
 982                        break;
 983                }
 984
 985                msg += linelen;
 986                len -= linelen;
 987                if (hdr) {
 988                        if (linelen == 1) {
 989                                hdr = 0;
 990                                if ((fmt != CMIT_FMT_ONELINE) && !subject)
 991                                        buf[offset++] = '\n';
 992                                continue;
 993                        }
 994                        if (fmt == CMIT_FMT_RAW) {
 995                                memcpy(buf + offset, line, linelen);
 996                                offset += linelen;
 997                                continue;
 998                        }
 999                        if (!memcmp(line, "parent ", 7)) {
1000                                if (linelen != 48)
1001                                        die("bad parent line in commit");
1002                                continue;
1003                        }
1004
1005                        if (!parents_shown) {
1006                                offset += add_merge_info(fmt, buf + offset,
1007                                                         commit, abbrev);
1008                                parents_shown = 1;
1009                                continue;
1010                        }
1011                        /*
1012                         * MEDIUM == DEFAULT shows only author with dates.
1013                         * FULL shows both authors but not dates.
1014                         * FULLER shows both authors and dates.
1015                         */
1016                        if (!memcmp(line, "author ", 7))
1017                                offset += add_user_info("Author", fmt,
1018                                                        buf + offset,
1019                                                        line + 7,
1020                                                        dmode,
1021                                                        encoding);
1022                        if (!memcmp(line, "committer ", 10) &&
1023                            (fmt == CMIT_FMT_FULL || fmt == CMIT_FMT_FULLER))
1024                                offset += add_user_info("Commit", fmt,
1025                                                        buf + offset,
1026                                                        line + 10,
1027                                                        dmode,
1028                                                        encoding);
1029                        continue;
1030                }
1031
1032                if (!subject)
1033                        body = 1;
1034
1035                if (is_empty_line(line, &linelen)) {
1036                        if (!seen_title)
1037                                continue;
1038                        if (!body)
1039                                continue;
1040                        if (subject)
1041                                continue;
1042                        if (fmt == CMIT_FMT_SHORT)
1043                                break;
1044                }
1045
1046                seen_title = 1;
1047                if (subject) {
1048                        int slen = strlen(subject);
1049                        memcpy(buf + offset, subject, slen);
1050                        offset += slen;
1051                        offset += add_rfc2047(buf + offset, line, linelen,
1052                                              encoding);
1053                }
1054                else {
1055                        memset(buf + offset, ' ', indent);
1056                        memcpy(buf + offset + indent, line, linelen);
1057                        offset += linelen + indent;
1058                }
1059                buf[offset++] = '\n';
1060                if (fmt == CMIT_FMT_ONELINE)
1061                        break;
1062                if (subject && plain_non_ascii) {
1063                        int sz;
1064                        char header[512];
1065                        const char *header_fmt =
1066                                "MIME-Version: 1.0\n"
1067                                "Content-Type: text/plain; charset=%s\n"
1068                                "Content-Transfer-Encoding: 8bit\n";
1069                        sz = snprintf(header, sizeof(header), header_fmt,
1070                                      encoding);
1071                        if (sizeof(header) < sz)
1072                                die("Encoding name %s too long", encoding);
1073                        memcpy(buf + offset, header, sz);
1074                        offset += sz;
1075                }
1076                if (after_subject) {
1077                        int slen = strlen(after_subject);
1078                        if (slen > space - offset - 1)
1079                                slen = space - offset - 1;
1080                        memcpy(buf + offset, after_subject, slen);
1081                        offset += slen;
1082                        after_subject = NULL;
1083                }
1084                subject = NULL;
1085        }
1086        while (offset && isspace(buf[offset-1]))
1087                offset--;
1088        /* Make sure there is an EOLN for the non-oneline case */
1089        if (fmt != CMIT_FMT_ONELINE)
1090                buf[offset++] = '\n';
1091        /*
1092         * make sure there is another EOLN to separate the headers from whatever
1093         * body the caller appends if we haven't already written a body
1094         */
1095        if (fmt == CMIT_FMT_EMAIL && !body)
1096                buf[offset++] = '\n';
1097        buf[offset] = '\0';
1098
1099        free(reencoded);
1100        return offset;
1101}
1102
1103struct commit *pop_commit(struct commit_list **stack)
1104{
1105        struct commit_list *top = *stack;
1106        struct commit *item = top ? top->item : NULL;
1107
1108        if (top) {
1109                *stack = top->next;
1110                free(top);
1111        }
1112        return item;
1113}
1114
1115int count_parents(struct commit * commit)
1116{
1117        int count;
1118        struct commit_list * parents = commit->parents;
1119        for (count = 0; parents; parents = parents->next,count++)
1120                ;
1121        return count;
1122}
1123
1124void topo_sort_default_setter(struct commit *c, void *data)
1125{
1126        c->util = data;
1127}
1128
1129void *topo_sort_default_getter(struct commit *c)
1130{
1131        return c->util;
1132}
1133
1134/*
1135 * Performs an in-place topological sort on the list supplied.
1136 */
1137void sort_in_topological_order(struct commit_list ** list, int lifo)
1138{
1139        sort_in_topological_order_fn(list, lifo, topo_sort_default_setter,
1140                                     topo_sort_default_getter);
1141}
1142
1143void sort_in_topological_order_fn(struct commit_list ** list, int lifo,
1144                                  topo_sort_set_fn_t setter,
1145                                  topo_sort_get_fn_t getter)
1146{
1147        struct commit_list * next = *list;
1148        struct commit_list * work = NULL, **insert;
1149        struct commit_list ** pptr = list;
1150        struct sort_node * nodes;
1151        struct sort_node * next_nodes;
1152        int count = 0;
1153
1154        /* determine the size of the list */
1155        while (next) {
1156                next = next->next;
1157                count++;
1158        }
1159        
1160        if (!count)
1161                return;
1162        /* allocate an array to help sort the list */
1163        nodes = xcalloc(count, sizeof(*nodes));
1164        /* link the list to the array */
1165        next_nodes = nodes;
1166        next=*list;
1167        while (next) {
1168                next_nodes->list_item = next;
1169                setter(next->item, next_nodes);
1170                next_nodes++;
1171                next = next->next;
1172        }
1173        /* update the indegree */
1174        next=*list;
1175        while (next) {
1176                struct commit_list * parents = next->item->parents;
1177                while (parents) {
1178                        struct commit * parent=parents->item;
1179                        struct sort_node * pn = (struct sort_node *) getter(parent);
1180
1181                        if (pn)
1182                                pn->indegree++;
1183                        parents=parents->next;
1184                }
1185                next=next->next;
1186        }
1187        /* 
1188         * find the tips
1189         *
1190         * tips are nodes not reachable from any other node in the list 
1191         * 
1192         * the tips serve as a starting set for the work queue.
1193         */
1194        next=*list;
1195        insert = &work;
1196        while (next) {
1197                struct sort_node * node = (struct sort_node *) getter(next->item);
1198
1199                if (node->indegree == 0) {
1200                        insert = &commit_list_insert(next->item, insert)->next;
1201                }
1202                next=next->next;
1203        }
1204
1205        /* process the list in topological order */
1206        if (!lifo)
1207                sort_by_date(&work);
1208        while (work) {
1209                struct commit * work_item = pop_commit(&work);
1210                struct sort_node * work_node = (struct sort_node *) getter(work_item);
1211                struct commit_list * parents = work_item->parents;
1212
1213                while (parents) {
1214                        struct commit * parent=parents->item;
1215                        struct sort_node * pn = (struct sort_node *) getter(parent);
1216
1217                        if (pn) {
1218                                /*
1219                                 * parents are only enqueued for emission 
1220                                 * when all their children have been emitted thereby
1221                                 * guaranteeing topological order.
1222                                 */
1223                                pn->indegree--;
1224                                if (!pn->indegree) {
1225                                        if (!lifo)
1226                                                insert_by_date(parent, &work);
1227                                        else
1228                                                commit_list_insert(parent, &work);
1229                                }
1230                        }
1231                        parents=parents->next;
1232                }
1233                /*
1234                 * work_item is a commit all of whose children
1235                 * have already been emitted. we can emit it now.
1236                 */
1237                *pptr = work_node->list_item;
1238                pptr = &(*pptr)->next;
1239                *pptr = NULL;
1240                setter(work_item, NULL);
1241        }
1242        free(nodes);
1243}
1244
1245/* merge-base stuff */
1246
1247/* bits #0..15 in revision.h */
1248#define PARENT1         (1u<<16)
1249#define PARENT2         (1u<<17)
1250#define STALE           (1u<<18)
1251#define RESULT          (1u<<19)
1252
1253static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
1254
1255static struct commit *interesting(struct commit_list *list)
1256{
1257        while (list) {
1258                struct commit *commit = list->item;
1259                list = list->next;
1260                if (commit->object.flags & STALE)
1261                        continue;
1262                return commit;
1263        }
1264        return NULL;
1265}
1266
1267static struct commit_list *merge_bases(struct commit *one, struct commit *two)
1268{
1269        struct commit_list *list = NULL;
1270        struct commit_list *result = NULL;
1271
1272        if (one == two)
1273                /* We do not mark this even with RESULT so we do not
1274                 * have to clean it up.
1275                 */
1276                return commit_list_insert(one, &result);
1277
1278        parse_commit(one);
1279        parse_commit(two);
1280
1281        one->object.flags |= PARENT1;
1282        two->object.flags |= PARENT2;
1283        insert_by_date(one, &list);
1284        insert_by_date(two, &list);
1285
1286        while (interesting(list)) {
1287                struct commit *commit;
1288                struct commit_list *parents;
1289                struct commit_list *n;
1290                int flags;
1291
1292                commit = list->item;
1293                n = list->next;
1294                free(list);
1295                list = n;
1296
1297                flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
1298                if (flags == (PARENT1 | PARENT2)) {
1299                        if (!(commit->object.flags & RESULT)) {
1300                                commit->object.flags |= RESULT;
1301                                insert_by_date(commit, &result);
1302                        }
1303                        /* Mark parents of a found merge stale */
1304                        flags |= STALE;
1305                }
1306                parents = commit->parents;
1307                while (parents) {
1308                        struct commit *p = parents->item;
1309                        parents = parents->next;
1310                        if ((p->object.flags & flags) == flags)
1311                                continue;
1312                        parse_commit(p);
1313                        p->object.flags |= flags;
1314                        insert_by_date(p, &list);
1315                }
1316        }
1317
1318        /* Clean up the result to remove stale ones */
1319        free_commit_list(list);
1320        list = result; result = NULL;
1321        while (list) {
1322                struct commit_list *n = list->next;
1323                if (!(list->item->object.flags & STALE))
1324                        insert_by_date(list->item, &result);
1325                free(list);
1326                list = n;
1327        }
1328        return result;
1329}
1330
1331struct commit_list *get_merge_bases(struct commit *one,
1332                                    struct commit *two,
1333                                    int cleanup)
1334{
1335        struct commit_list *list;
1336        struct commit **rslt;
1337        struct commit_list *result;
1338        int cnt, i, j;
1339
1340        result = merge_bases(one, two);
1341        if (one == two)
1342                return result;
1343        if (!result || !result->next) {
1344                if (cleanup) {
1345                        clear_commit_marks(one, all_flags);
1346                        clear_commit_marks(two, all_flags);
1347                }
1348                return result;
1349        }
1350
1351        /* There are more than one */
1352        cnt = 0;
1353        list = result;
1354        while (list) {
1355                list = list->next;
1356                cnt++;
1357        }
1358        rslt = xcalloc(cnt, sizeof(*rslt));
1359        for (list = result, i = 0; list; list = list->next)
1360                rslt[i++] = list->item;
1361        free_commit_list(result);
1362
1363        clear_commit_marks(one, all_flags);
1364        clear_commit_marks(two, all_flags);
1365        for (i = 0; i < cnt - 1; i++) {
1366                for (j = i+1; j < cnt; j++) {
1367                        if (!rslt[i] || !rslt[j])
1368                                continue;
1369                        result = merge_bases(rslt[i], rslt[j]);
1370                        clear_commit_marks(rslt[i], all_flags);
1371                        clear_commit_marks(rslt[j], all_flags);
1372                        for (list = result; list; list = list->next) {
1373                                if (rslt[i] == list->item)
1374                                        rslt[i] = NULL;
1375                                if (rslt[j] == list->item)
1376                                        rslt[j] = NULL;
1377                        }
1378                }
1379        }
1380
1381        /* Surviving ones in rslt[] are the independent results */
1382        result = NULL;
1383        for (i = 0; i < cnt; i++) {
1384                if (rslt[i])
1385                        insert_by_date(rslt[i], &result);
1386        }
1387        free(rslt);
1388        return result;
1389}
1390
1391int in_merge_bases(struct commit *commit, struct commit **reference, int num)
1392{
1393        struct commit_list *bases, *b;
1394        int ret = 0;
1395
1396        if (num == 1)
1397                bases = get_merge_bases(commit, *reference, 1);
1398        else
1399                die("not yet");
1400        for (b = bases; b; b = b->next) {
1401                if (!hashcmp(commit->object.sha1, b->item->object.sha1)) {
1402                        ret = 1;
1403                        break;
1404                }
1405        }
1406
1407        free_commit_list(bases);
1408        return ret;
1409}