commit.con commit commit: allow prepare_commit_graft to handle arbitrary repositories (2f6c767)
   1#include "cache.h"
   2#include "tag.h"
   3#include "commit.h"
   4#include "repository.h"
   5#include "object-store.h"
   6#include "pkt-line.h"
   7#include "utf8.h"
   8#include "diff.h"
   9#include "revision.h"
  10#include "notes.h"
  11#include "alloc.h"
  12#include "gpg-interface.h"
  13#include "mergesort.h"
  14#include "commit-slab.h"
  15#include "prio-queue.h"
  16#include "sha1-lookup.h"
  17#include "wt-status.h"
  18
  19static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
  20
  21int save_commit_buffer = 1;
  22
  23const char *commit_type = "commit";
  24
  25struct commit *lookup_commit_reference_gently(const struct object_id *oid,
  26                                              int quiet)
  27{
  28        struct object *obj = deref_tag(parse_object(oid), NULL, 0);
  29
  30        if (!obj)
  31                return NULL;
  32        return object_as_type(obj, OBJ_COMMIT, quiet);
  33}
  34
  35struct commit *lookup_commit_reference(const struct object_id *oid)
  36{
  37        return lookup_commit_reference_gently(oid, 0);
  38}
  39
  40struct commit *lookup_commit_or_die(const struct object_id *oid, const char *ref_name)
  41{
  42        struct commit *c = lookup_commit_reference(oid);
  43        if (!c)
  44                die(_("could not parse %s"), ref_name);
  45        if (oidcmp(oid, &c->object.oid)) {
  46                warning(_("%s %s is not a commit!"),
  47                        ref_name, oid_to_hex(oid));
  48        }
  49        return c;
  50}
  51
  52struct commit *lookup_commit(const struct object_id *oid)
  53{
  54        struct object *obj = lookup_object(oid->hash);
  55        if (!obj)
  56                return create_object(the_repository, oid->hash,
  57                                     alloc_commit_node(the_repository));
  58        return object_as_type(obj, OBJ_COMMIT, 0);
  59}
  60
  61struct commit *lookup_commit_reference_by_name(const char *name)
  62{
  63        struct object_id oid;
  64        struct commit *commit;
  65
  66        if (get_oid_committish(name, &oid))
  67                return NULL;
  68        commit = lookup_commit_reference(&oid);
  69        if (parse_commit(commit))
  70                return NULL;
  71        return commit;
  72}
  73
  74static timestamp_t parse_commit_date(const char *buf, const char *tail)
  75{
  76        const char *dateptr;
  77
  78        if (buf + 6 >= tail)
  79                return 0;
  80        if (memcmp(buf, "author", 6))
  81                return 0;
  82        while (buf < tail && *buf++ != '\n')
  83                /* nada */;
  84        if (buf + 9 >= tail)
  85                return 0;
  86        if (memcmp(buf, "committer", 9))
  87                return 0;
  88        while (buf < tail && *buf++ != '>')
  89                /* nada */;
  90        if (buf >= tail)
  91                return 0;
  92        dateptr = buf;
  93        while (buf < tail && *buf++ != '\n')
  94                /* nada */;
  95        if (buf >= tail)
  96                return 0;
  97        /* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */
  98        return parse_timestamp(dateptr, NULL, 10);
  99}
 100
 101static const unsigned char *commit_graft_sha1_access(size_t index, void *table)
 102{
 103        struct commit_graft **commit_graft_table = table;
 104        return commit_graft_table[index]->oid.hash;
 105}
 106
 107static int commit_graft_pos(struct repository *r, const unsigned char *sha1)
 108{
 109        return sha1_pos(sha1, r->parsed_objects->grafts,
 110                        r->parsed_objects->grafts_nr,
 111                        commit_graft_sha1_access);
 112}
 113
 114int register_commit_graft(struct repository *r, struct commit_graft *graft,
 115                          int ignore_dups)
 116{
 117        int pos = commit_graft_pos(r, graft->oid.hash);
 118
 119        if (0 <= pos) {
 120                if (ignore_dups)
 121                        free(graft);
 122                else {
 123                        free(r->parsed_objects->grafts[pos]);
 124                        r->parsed_objects->grafts[pos] = graft;
 125                }
 126                return 1;
 127        }
 128        pos = -pos - 1;
 129        ALLOC_GROW(r->parsed_objects->grafts,
 130                   r->parsed_objects->grafts_nr + 1,
 131                   r->parsed_objects->grafts_alloc);
 132        r->parsed_objects->grafts_nr++;
 133        if (pos < r->parsed_objects->grafts_nr)
 134                memmove(r->parsed_objects->grafts + pos + 1,
 135                        r->parsed_objects->grafts + pos,
 136                        (r->parsed_objects->grafts_nr - pos - 1) *
 137                        sizeof(*r->parsed_objects->grafts));
 138        r->parsed_objects->grafts[pos] = graft;
 139        return 0;
 140}
 141
 142struct commit_graft *read_graft_line(struct strbuf *line)
 143{
 144        /* The format is just "Commit Parent1 Parent2 ...\n" */
 145        int i, phase;
 146        const char *tail = NULL;
 147        struct commit_graft *graft = NULL;
 148        struct object_id dummy_oid, *oid;
 149
 150        strbuf_rtrim(line);
 151        if (!line->len || line->buf[0] == '#')
 152                return NULL;
 153        /*
 154         * phase 0 verifies line, counts hashes in line and allocates graft
 155         * phase 1 fills graft
 156         */
 157        for (phase = 0; phase < 2; phase++) {
 158                oid = graft ? &graft->oid : &dummy_oid;
 159                if (parse_oid_hex(line->buf, oid, &tail))
 160                        goto bad_graft_data;
 161                for (i = 0; *tail != '\0'; i++) {
 162                        oid = graft ? &graft->parent[i] : &dummy_oid;
 163                        if (!isspace(*tail++) || parse_oid_hex(tail, oid, &tail))
 164                                goto bad_graft_data;
 165                }
 166                if (!graft) {
 167                        graft = xmalloc(st_add(sizeof(*graft),
 168                                               st_mult(sizeof(struct object_id), i)));
 169                        graft->nr_parent = i;
 170                }
 171        }
 172        return graft;
 173
 174bad_graft_data:
 175        error("bad graft data: %s", line->buf);
 176        assert(!graft);
 177        return NULL;
 178}
 179
 180static int read_graft_file(struct repository *r, const char *graft_file)
 181{
 182        FILE *fp = fopen_or_warn(graft_file, "r");
 183        struct strbuf buf = STRBUF_INIT;
 184        if (!fp)
 185                return -1;
 186        while (!strbuf_getwholeline(&buf, fp, '\n')) {
 187                /* The format is just "Commit Parent1 Parent2 ...\n" */
 188                struct commit_graft *graft = read_graft_line(&buf);
 189                if (!graft)
 190                        continue;
 191                if (register_commit_graft(r, graft, 1))
 192                        error("duplicate graft data: %s", buf.buf);
 193        }
 194        fclose(fp);
 195        strbuf_release(&buf);
 196        return 0;
 197}
 198
 199static void prepare_commit_graft(struct repository *r)
 200{
 201        char *graft_file;
 202
 203        if (r->parsed_objects->commit_graft_prepared)
 204                return;
 205        graft_file = get_graft_file(r);
 206        read_graft_file(r, graft_file);
 207        /* make sure shallows are read */
 208        is_repository_shallow(r);
 209        r->parsed_objects->commit_graft_prepared = 1;
 210}
 211
 212struct commit_graft *lookup_commit_graft_the_repository(const struct object_id *oid)
 213{
 214        int pos;
 215        prepare_commit_graft(the_repository);
 216        pos = commit_graft_pos(the_repository, oid->hash);
 217        if (pos < 0)
 218                return NULL;
 219        return the_repository->parsed_objects->grafts[pos];
 220}
 221
 222int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
 223{
 224        int i, ret;
 225        for (i = ret = 0; i < the_repository->parsed_objects->grafts_nr && !ret; i++)
 226                ret = fn(the_repository->parsed_objects->grafts[i], cb_data);
 227        return ret;
 228}
 229
 230int unregister_shallow(const struct object_id *oid)
 231{
 232        int pos = commit_graft_pos(the_repository, oid->hash);
 233        if (pos < 0)
 234                return -1;
 235        if (pos + 1 < the_repository->parsed_objects->grafts_nr)
 236                MOVE_ARRAY(the_repository->parsed_objects->grafts + pos,
 237                           the_repository->parsed_objects->grafts + pos + 1,
 238                           the_repository->parsed_objects->grafts_nr - pos - 1);
 239        the_repository->parsed_objects->grafts_nr--;
 240        return 0;
 241}
 242
 243struct commit_buffer {
 244        void *buffer;
 245        unsigned long size;
 246};
 247define_commit_slab(buffer_slab, struct commit_buffer);
 248static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
 249
 250void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
 251{
 252        struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
 253        v->buffer = buffer;
 254        v->size = size;
 255}
 256
 257const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
 258{
 259        struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 260        if (!v) {
 261                if (sizep)
 262                        *sizep = 0;
 263                return NULL;
 264        }
 265        if (sizep)
 266                *sizep = v->size;
 267        return v->buffer;
 268}
 269
 270const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
 271{
 272        const void *ret = get_cached_commit_buffer(commit, sizep);
 273        if (!ret) {
 274                enum object_type type;
 275                unsigned long size;
 276                ret = read_object_file(&commit->object.oid, &type, &size);
 277                if (!ret)
 278                        die("cannot read commit object %s",
 279                            oid_to_hex(&commit->object.oid));
 280                if (type != OBJ_COMMIT)
 281                        die("expected commit for %s, got %s",
 282                            oid_to_hex(&commit->object.oid), type_name(type));
 283                if (sizep)
 284                        *sizep = size;
 285        }
 286        return ret;
 287}
 288
 289void unuse_commit_buffer(const struct commit *commit, const void *buffer)
 290{
 291        struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 292        if (!(v && v->buffer == buffer))
 293                free((void *)buffer);
 294}
 295
 296void free_commit_buffer(struct commit *commit)
 297{
 298        struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 299        if (v) {
 300                FREE_AND_NULL(v->buffer);
 301                v->size = 0;
 302        }
 303}
 304
 305void release_commit_memory(struct commit *c)
 306{
 307        c->tree = NULL;
 308        c->index = 0;
 309        free_commit_buffer(c);
 310        free_commit_list(c->parents);
 311        /* TODO: what about commit->util? */
 312
 313        c->object.parsed = 0;
 314}
 315
 316const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
 317{
 318        struct commit_buffer *v = buffer_slab_peek(&buffer_slab, commit);
 319        void *ret;
 320
 321        if (!v) {
 322                if (sizep)
 323                        *sizep = 0;
 324                return NULL;
 325        }
 326        ret = v->buffer;
 327        if (sizep)
 328                *sizep = v->size;
 329
 330        v->buffer = NULL;
 331        v->size = 0;
 332        return ret;
 333}
 334
 335int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
 336{
 337        const char *tail = buffer;
 338        const char *bufptr = buffer;
 339        struct object_id parent;
 340        struct commit_list **pptr;
 341        struct commit_graft *graft;
 342        const int tree_entry_len = GIT_SHA1_HEXSZ + 5;
 343        const int parent_entry_len = GIT_SHA1_HEXSZ + 7;
 344
 345        if (item->object.parsed)
 346                return 0;
 347        item->object.parsed = 1;
 348        tail += size;
 349        if (tail <= bufptr + tree_entry_len + 1 || memcmp(bufptr, "tree ", 5) ||
 350                        bufptr[tree_entry_len] != '\n')
 351                return error("bogus commit object %s", oid_to_hex(&item->object.oid));
 352        if (get_sha1_hex(bufptr + 5, parent.hash) < 0)
 353                return error("bad tree pointer in commit %s",
 354                             oid_to_hex(&item->object.oid));
 355        item->tree = lookup_tree(&parent);
 356        bufptr += tree_entry_len + 1; /* "tree " + "hex sha1" + "\n" */
 357        pptr = &item->parents;
 358
 359        graft = lookup_commit_graft(the_repository, &item->object.oid);
 360        while (bufptr + parent_entry_len < tail && !memcmp(bufptr, "parent ", 7)) {
 361                struct commit *new_parent;
 362
 363                if (tail <= bufptr + parent_entry_len + 1 ||
 364                    get_sha1_hex(bufptr + 7, parent.hash) ||
 365                    bufptr[parent_entry_len] != '\n')
 366                        return error("bad parents in commit %s", oid_to_hex(&item->object.oid));
 367                bufptr += parent_entry_len + 1;
 368                /*
 369                 * The clone is shallow if nr_parent < 0, and we must
 370                 * not traverse its real parents even when we unhide them.
 371                 */
 372                if (graft && (graft->nr_parent < 0 || grafts_replace_parents))
 373                        continue;
 374                new_parent = lookup_commit(&parent);
 375                if (new_parent)
 376                        pptr = &commit_list_insert(new_parent, pptr)->next;
 377        }
 378        if (graft) {
 379                int i;
 380                struct commit *new_parent;
 381                for (i = 0; i < graft->nr_parent; i++) {
 382                        new_parent = lookup_commit(&graft->parent[i]);
 383                        if (!new_parent)
 384                                continue;
 385                        pptr = &commit_list_insert(new_parent, pptr)->next;
 386                }
 387        }
 388        item->date = parse_commit_date(bufptr, tail);
 389
 390        return 0;
 391}
 392
 393int parse_commit_gently(struct commit *item, int quiet_on_missing)
 394{
 395        enum object_type type;
 396        void *buffer;
 397        unsigned long size;
 398        int ret;
 399
 400        if (!item)
 401                return -1;
 402        if (item->object.parsed)
 403                return 0;
 404        buffer = read_object_file(&item->object.oid, &type, &size);
 405        if (!buffer)
 406                return quiet_on_missing ? -1 :
 407                        error("Could not read %s",
 408                             oid_to_hex(&item->object.oid));
 409        if (type != OBJ_COMMIT) {
 410                free(buffer);
 411                return error("Object %s not a commit",
 412                             oid_to_hex(&item->object.oid));
 413        }
 414        ret = parse_commit_buffer(item, buffer, size);
 415        if (save_commit_buffer && !ret) {
 416                set_commit_buffer(item, buffer, size);
 417                return 0;
 418        }
 419        free(buffer);
 420        return ret;
 421}
 422
 423void parse_commit_or_die(struct commit *item)
 424{
 425        if (parse_commit(item))
 426                die("unable to parse commit %s",
 427                    item ? oid_to_hex(&item->object.oid) : "(null)");
 428}
 429
 430int find_commit_subject(const char *commit_buffer, const char **subject)
 431{
 432        const char *eol;
 433        const char *p = commit_buffer;
 434
 435        while (*p && (*p != '\n' || p[1] != '\n'))
 436                p++;
 437        if (*p) {
 438                p = skip_blank_lines(p + 2);
 439                eol = strchrnul(p, '\n');
 440        } else
 441                eol = p;
 442
 443        *subject = p;
 444
 445        return eol - p;
 446}
 447
 448struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
 449{
 450        struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
 451        new_list->item = item;
 452        new_list->next = *list_p;
 453        *list_p = new_list;
 454        return new_list;
 455}
 456
 457unsigned commit_list_count(const struct commit_list *l)
 458{
 459        unsigned c = 0;
 460        for (; l; l = l->next )
 461                c++;
 462        return c;
 463}
 464
 465struct commit_list *copy_commit_list(struct commit_list *list)
 466{
 467        struct commit_list *head = NULL;
 468        struct commit_list **pp = &head;
 469        while (list) {
 470                pp = commit_list_append(list->item, pp);
 471                list = list->next;
 472        }
 473        return head;
 474}
 475
 476void free_commit_list(struct commit_list *list)
 477{
 478        while (list)
 479                pop_commit(&list);
 480}
 481
 482struct commit_list * commit_list_insert_by_date(struct commit *item, struct commit_list **list)
 483{
 484        struct commit_list **pp = list;
 485        struct commit_list *p;
 486        while ((p = *pp) != NULL) {
 487                if (p->item->date < item->date) {
 488                        break;
 489                }
 490                pp = &p->next;
 491        }
 492        return commit_list_insert(item, pp);
 493}
 494
 495static int commit_list_compare_by_date(const void *a, const void *b)
 496{
 497        timestamp_t a_date = ((const struct commit_list *)a)->item->date;
 498        timestamp_t b_date = ((const struct commit_list *)b)->item->date;
 499        if (a_date < b_date)
 500                return 1;
 501        if (a_date > b_date)
 502                return -1;
 503        return 0;
 504}
 505
 506static void *commit_list_get_next(const void *a)
 507{
 508        return ((const struct commit_list *)a)->next;
 509}
 510
 511static void commit_list_set_next(void *a, void *next)
 512{
 513        ((struct commit_list *)a)->next = next;
 514}
 515
 516void commit_list_sort_by_date(struct commit_list **list)
 517{
 518        *list = llist_mergesort(*list, commit_list_get_next, commit_list_set_next,
 519                                commit_list_compare_by_date);
 520}
 521
 522struct commit *pop_most_recent_commit(struct commit_list **list,
 523                                      unsigned int mark)
 524{
 525        struct commit *ret = pop_commit(list);
 526        struct commit_list *parents = ret->parents;
 527
 528        while (parents) {
 529                struct commit *commit = parents->item;
 530                if (!parse_commit(commit) && !(commit->object.flags & mark)) {
 531                        commit->object.flags |= mark;
 532                        commit_list_insert_by_date(commit, list);
 533                }
 534                parents = parents->next;
 535        }
 536        return ret;
 537}
 538
 539static void clear_commit_marks_1(struct commit_list **plist,
 540                                 struct commit *commit, unsigned int mark)
 541{
 542        while (commit) {
 543                struct commit_list *parents;
 544
 545                if (!(mark & commit->object.flags))
 546                        return;
 547
 548                commit->object.flags &= ~mark;
 549
 550                parents = commit->parents;
 551                if (!parents)
 552                        return;
 553
 554                while ((parents = parents->next))
 555                        commit_list_insert(parents->item, plist);
 556
 557                commit = commit->parents->item;
 558        }
 559}
 560
 561void clear_commit_marks_many(int nr, struct commit **commit, unsigned int mark)
 562{
 563        struct commit_list *list = NULL;
 564
 565        while (nr--) {
 566                clear_commit_marks_1(&list, *commit, mark);
 567                commit++;
 568        }
 569        while (list)
 570                clear_commit_marks_1(&list, pop_commit(&list), mark);
 571}
 572
 573void clear_commit_marks(struct commit *commit, unsigned int mark)
 574{
 575        clear_commit_marks_many(1, &commit, mark);
 576}
 577
 578struct commit *pop_commit(struct commit_list **stack)
 579{
 580        struct commit_list *top = *stack;
 581        struct commit *item = top ? top->item : NULL;
 582
 583        if (top) {
 584                *stack = top->next;
 585                free(top);
 586        }
 587        return item;
 588}
 589
 590/*
 591 * Topological sort support
 592 */
 593
 594/* count number of children that have not been emitted */
 595define_commit_slab(indegree_slab, int);
 596
 597/* record author-date for each commit object */
 598define_commit_slab(author_date_slab, unsigned long);
 599
 600static void record_author_date(struct author_date_slab *author_date,
 601                               struct commit *commit)
 602{
 603        const char *buffer = get_commit_buffer(commit, NULL);
 604        struct ident_split ident;
 605        const char *ident_line;
 606        size_t ident_len;
 607        char *date_end;
 608        timestamp_t date;
 609
 610        ident_line = find_commit_header(buffer, "author", &ident_len);
 611        if (!ident_line)
 612                goto fail_exit; /* no author line */
 613        if (split_ident_line(&ident, ident_line, ident_len) ||
 614            !ident.date_begin || !ident.date_end)
 615                goto fail_exit; /* malformed "author" line */
 616
 617        date = parse_timestamp(ident.date_begin, &date_end, 10);
 618        if (date_end != ident.date_end)
 619                goto fail_exit; /* malformed date */
 620        *(author_date_slab_at(author_date, commit)) = date;
 621
 622fail_exit:
 623        unuse_commit_buffer(commit, buffer);
 624}
 625
 626static int compare_commits_by_author_date(const void *a_, const void *b_,
 627                                          void *cb_data)
 628{
 629        const struct commit *a = a_, *b = b_;
 630        struct author_date_slab *author_date = cb_data;
 631        timestamp_t a_date = *(author_date_slab_at(author_date, a));
 632        timestamp_t b_date = *(author_date_slab_at(author_date, b));
 633
 634        /* newer commits with larger date first */
 635        if (a_date < b_date)
 636                return 1;
 637        else if (a_date > b_date)
 638                return -1;
 639        return 0;
 640}
 641
 642int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
 643{
 644        const struct commit *a = a_, *b = b_;
 645        /* newer commits with larger date first */
 646        if (a->date < b->date)
 647                return 1;
 648        else if (a->date > b->date)
 649                return -1;
 650        return 0;
 651}
 652
 653/*
 654 * Performs an in-place topological sort on the list supplied.
 655 */
 656void sort_in_topological_order(struct commit_list **list, enum rev_sort_order sort_order)
 657{
 658        struct commit_list *next, *orig = *list;
 659        struct commit_list **pptr;
 660        struct indegree_slab indegree;
 661        struct prio_queue queue;
 662        struct commit *commit;
 663        struct author_date_slab author_date;
 664
 665        if (!orig)
 666                return;
 667        *list = NULL;
 668
 669        init_indegree_slab(&indegree);
 670        memset(&queue, '\0', sizeof(queue));
 671
 672        switch (sort_order) {
 673        default: /* REV_SORT_IN_GRAPH_ORDER */
 674                queue.compare = NULL;
 675                break;
 676        case REV_SORT_BY_COMMIT_DATE:
 677                queue.compare = compare_commits_by_commit_date;
 678                break;
 679        case REV_SORT_BY_AUTHOR_DATE:
 680                init_author_date_slab(&author_date);
 681                queue.compare = compare_commits_by_author_date;
 682                queue.cb_data = &author_date;
 683                break;
 684        }
 685
 686        /* Mark them and clear the indegree */
 687        for (next = orig; next; next = next->next) {
 688                struct commit *commit = next->item;
 689                *(indegree_slab_at(&indegree, commit)) = 1;
 690                /* also record the author dates, if needed */
 691                if (sort_order == REV_SORT_BY_AUTHOR_DATE)
 692                        record_author_date(&author_date, commit);
 693        }
 694
 695        /* update the indegree */
 696        for (next = orig; next; next = next->next) {
 697                struct commit_list *parents = next->item->parents;
 698                while (parents) {
 699                        struct commit *parent = parents->item;
 700                        int *pi = indegree_slab_at(&indegree, parent);
 701
 702                        if (*pi)
 703                                (*pi)++;
 704                        parents = parents->next;
 705                }
 706        }
 707
 708        /*
 709         * find the tips
 710         *
 711         * tips are nodes not reachable from any other node in the list
 712         *
 713         * the tips serve as a starting set for the work queue.
 714         */
 715        for (next = orig; next; next = next->next) {
 716                struct commit *commit = next->item;
 717
 718                if (*(indegree_slab_at(&indegree, commit)) == 1)
 719                        prio_queue_put(&queue, commit);
 720        }
 721
 722        /*
 723         * This is unfortunate; the initial tips need to be shown
 724         * in the order given from the revision traversal machinery.
 725         */
 726        if (sort_order == REV_SORT_IN_GRAPH_ORDER)
 727                prio_queue_reverse(&queue);
 728
 729        /* We no longer need the commit list */
 730        free_commit_list(orig);
 731
 732        pptr = list;
 733        *list = NULL;
 734        while ((commit = prio_queue_get(&queue)) != NULL) {
 735                struct commit_list *parents;
 736
 737                for (parents = commit->parents; parents ; parents = parents->next) {
 738                        struct commit *parent = parents->item;
 739                        int *pi = indegree_slab_at(&indegree, parent);
 740
 741                        if (!*pi)
 742                                continue;
 743
 744                        /*
 745                         * parents are only enqueued for emission
 746                         * when all their children have been emitted thereby
 747                         * guaranteeing topological order.
 748                         */
 749                        if (--(*pi) == 1)
 750                                prio_queue_put(&queue, parent);
 751                }
 752                /*
 753                 * all children of commit have already been
 754                 * emitted. we can emit it now.
 755                 */
 756                *(indegree_slab_at(&indegree, commit)) = 0;
 757
 758                pptr = &commit_list_insert(commit, pptr)->next;
 759        }
 760
 761        clear_indegree_slab(&indegree);
 762        clear_prio_queue(&queue);
 763        if (sort_order == REV_SORT_BY_AUTHOR_DATE)
 764                clear_author_date_slab(&author_date);
 765}
 766
 767/* merge-base stuff */
 768
 769/* Remember to update object flag allocation in object.h */
 770#define PARENT1         (1u<<16)
 771#define PARENT2         (1u<<17)
 772#define STALE           (1u<<18)
 773#define RESULT          (1u<<19)
 774
 775static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
 776
 777static int queue_has_nonstale(struct prio_queue *queue)
 778{
 779        int i;
 780        for (i = 0; i < queue->nr; i++) {
 781                struct commit *commit = queue->array[i].data;
 782                if (!(commit->object.flags & STALE))
 783                        return 1;
 784        }
 785        return 0;
 786}
 787
 788/* all input commits in one and twos[] must have been parsed! */
 789static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
 790{
 791        struct prio_queue queue = { compare_commits_by_commit_date };
 792        struct commit_list *result = NULL;
 793        int i;
 794
 795        one->object.flags |= PARENT1;
 796        if (!n) {
 797                commit_list_append(one, &result);
 798                return result;
 799        }
 800        prio_queue_put(&queue, one);
 801
 802        for (i = 0; i < n; i++) {
 803                twos[i]->object.flags |= PARENT2;
 804                prio_queue_put(&queue, twos[i]);
 805        }
 806
 807        while (queue_has_nonstale(&queue)) {
 808                struct commit *commit = prio_queue_get(&queue);
 809                struct commit_list *parents;
 810                int flags;
 811
 812                flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
 813                if (flags == (PARENT1 | PARENT2)) {
 814                        if (!(commit->object.flags & RESULT)) {
 815                                commit->object.flags |= RESULT;
 816                                commit_list_insert_by_date(commit, &result);
 817                        }
 818                        /* Mark parents of a found merge stale */
 819                        flags |= STALE;
 820                }
 821                parents = commit->parents;
 822                while (parents) {
 823                        struct commit *p = parents->item;
 824                        parents = parents->next;
 825                        if ((p->object.flags & flags) == flags)
 826                                continue;
 827                        if (parse_commit(p))
 828                                return NULL;
 829                        p->object.flags |= flags;
 830                        prio_queue_put(&queue, p);
 831                }
 832        }
 833
 834        clear_prio_queue(&queue);
 835        return result;
 836}
 837
 838static struct commit_list *merge_bases_many(struct commit *one, int n, struct commit **twos)
 839{
 840        struct commit_list *list = NULL;
 841        struct commit_list *result = NULL;
 842        int i;
 843
 844        for (i = 0; i < n; i++) {
 845                if (one == twos[i])
 846                        /*
 847                         * We do not mark this even with RESULT so we do not
 848                         * have to clean it up.
 849                         */
 850                        return commit_list_insert(one, &result);
 851        }
 852
 853        if (parse_commit(one))
 854                return NULL;
 855        for (i = 0; i < n; i++) {
 856                if (parse_commit(twos[i]))
 857                        return NULL;
 858        }
 859
 860        list = paint_down_to_common(one, n, twos);
 861
 862        while (list) {
 863                struct commit *commit = pop_commit(&list);
 864                if (!(commit->object.flags & STALE))
 865                        commit_list_insert_by_date(commit, &result);
 866        }
 867        return result;
 868}
 869
 870struct commit_list *get_octopus_merge_bases(struct commit_list *in)
 871{
 872        struct commit_list *i, *j, *k, *ret = NULL;
 873
 874        if (!in)
 875                return ret;
 876
 877        commit_list_insert(in->item, &ret);
 878
 879        for (i = in->next; i; i = i->next) {
 880                struct commit_list *new_commits = NULL, *end = NULL;
 881
 882                for (j = ret; j; j = j->next) {
 883                        struct commit_list *bases;
 884                        bases = get_merge_bases(i->item, j->item);
 885                        if (!new_commits)
 886                                new_commits = bases;
 887                        else
 888                                end->next = bases;
 889                        for (k = bases; k; k = k->next)
 890                                end = k;
 891                }
 892                ret = new_commits;
 893        }
 894        return ret;
 895}
 896
 897static int remove_redundant(struct commit **array, int cnt)
 898{
 899        /*
 900         * Some commit in the array may be an ancestor of
 901         * another commit.  Move such commit to the end of
 902         * the array, and return the number of commits that
 903         * are independent from each other.
 904         */
 905        struct commit **work;
 906        unsigned char *redundant;
 907        int *filled_index;
 908        int i, j, filled;
 909
 910        work = xcalloc(cnt, sizeof(*work));
 911        redundant = xcalloc(cnt, 1);
 912        ALLOC_ARRAY(filled_index, cnt - 1);
 913
 914        for (i = 0; i < cnt; i++)
 915                parse_commit(array[i]);
 916        for (i = 0; i < cnt; i++) {
 917                struct commit_list *common;
 918
 919                if (redundant[i])
 920                        continue;
 921                for (j = filled = 0; j < cnt; j++) {
 922                        if (i == j || redundant[j])
 923                                continue;
 924                        filled_index[filled] = j;
 925                        work[filled++] = array[j];
 926                }
 927                common = paint_down_to_common(array[i], filled, work);
 928                if (array[i]->object.flags & PARENT2)
 929                        redundant[i] = 1;
 930                for (j = 0; j < filled; j++)
 931                        if (work[j]->object.flags & PARENT1)
 932                                redundant[filled_index[j]] = 1;
 933                clear_commit_marks(array[i], all_flags);
 934                clear_commit_marks_many(filled, work, all_flags);
 935                free_commit_list(common);
 936        }
 937
 938        /* Now collect the result */
 939        COPY_ARRAY(work, array, cnt);
 940        for (i = filled = 0; i < cnt; i++)
 941                if (!redundant[i])
 942                        array[filled++] = work[i];
 943        for (j = filled, i = 0; i < cnt; i++)
 944                if (redundant[i])
 945                        array[j++] = work[i];
 946        free(work);
 947        free(redundant);
 948        free(filled_index);
 949        return filled;
 950}
 951
 952static struct commit_list *get_merge_bases_many_0(struct commit *one,
 953                                                  int n,
 954                                                  struct commit **twos,
 955                                                  int cleanup)
 956{
 957        struct commit_list *list;
 958        struct commit **rslt;
 959        struct commit_list *result;
 960        int cnt, i;
 961
 962        result = merge_bases_many(one, n, twos);
 963        for (i = 0; i < n; i++) {
 964                if (one == twos[i])
 965                        return result;
 966        }
 967        if (!result || !result->next) {
 968                if (cleanup) {
 969                        clear_commit_marks(one, all_flags);
 970                        clear_commit_marks_many(n, twos, all_flags);
 971                }
 972                return result;
 973        }
 974
 975        /* There are more than one */
 976        cnt = commit_list_count(result);
 977        rslt = xcalloc(cnt, sizeof(*rslt));
 978        for (list = result, i = 0; list; list = list->next)
 979                rslt[i++] = list->item;
 980        free_commit_list(result);
 981
 982        clear_commit_marks(one, all_flags);
 983        clear_commit_marks_many(n, twos, all_flags);
 984
 985        cnt = remove_redundant(rslt, cnt);
 986        result = NULL;
 987        for (i = 0; i < cnt; i++)
 988                commit_list_insert_by_date(rslt[i], &result);
 989        free(rslt);
 990        return result;
 991}
 992
 993struct commit_list *get_merge_bases_many(struct commit *one,
 994                                         int n,
 995                                         struct commit **twos)
 996{
 997        return get_merge_bases_many_0(one, n, twos, 1);
 998}
 999
1000struct commit_list *get_merge_bases_many_dirty(struct commit *one,
1001                                               int n,
1002                                               struct commit **twos)
1003{
1004        return get_merge_bases_many_0(one, n, twos, 0);
1005}
1006
1007struct commit_list *get_merge_bases(struct commit *one, struct commit *two)
1008{
1009        return get_merge_bases_many_0(one, 1, &two, 1);
1010}
1011
1012/*
1013 * Is "commit" a descendant of one of the elements on the "with_commit" list?
1014 */
1015int is_descendant_of(struct commit *commit, struct commit_list *with_commit)
1016{
1017        if (!with_commit)
1018                return 1;
1019        while (with_commit) {
1020                struct commit *other;
1021
1022                other = with_commit->item;
1023                with_commit = with_commit->next;
1024                if (in_merge_bases(other, commit))
1025                        return 1;
1026        }
1027        return 0;
1028}
1029
1030/*
1031 * Is "commit" an ancestor of one of the "references"?
1032 */
1033int in_merge_bases_many(struct commit *commit, int nr_reference, struct commit **reference)
1034{
1035        struct commit_list *bases;
1036        int ret = 0, i;
1037
1038        if (parse_commit(commit))
1039                return ret;
1040        for (i = 0; i < nr_reference; i++)
1041                if (parse_commit(reference[i]))
1042                        return ret;
1043
1044        bases = paint_down_to_common(commit, nr_reference, reference);
1045        if (commit->object.flags & PARENT2)
1046                ret = 1;
1047        clear_commit_marks(commit, all_flags);
1048        clear_commit_marks_many(nr_reference, reference, all_flags);
1049        free_commit_list(bases);
1050        return ret;
1051}
1052
1053/*
1054 * Is "commit" an ancestor of (i.e. reachable from) the "reference"?
1055 */
1056int in_merge_bases(struct commit *commit, struct commit *reference)
1057{
1058        return in_merge_bases_many(commit, 1, &reference);
1059}
1060
1061struct commit_list *reduce_heads(struct commit_list *heads)
1062{
1063        struct commit_list *p;
1064        struct commit_list *result = NULL, **tail = &result;
1065        struct commit **array;
1066        int num_head, i;
1067
1068        if (!heads)
1069                return NULL;
1070
1071        /* Uniquify */
1072        for (p = heads; p; p = p->next)
1073                p->item->object.flags &= ~STALE;
1074        for (p = heads, num_head = 0; p; p = p->next) {
1075                if (p->item->object.flags & STALE)
1076                        continue;
1077                p->item->object.flags |= STALE;
1078                num_head++;
1079        }
1080        array = xcalloc(num_head, sizeof(*array));
1081        for (p = heads, i = 0; p; p = p->next) {
1082                if (p->item->object.flags & STALE) {
1083                        array[i++] = p->item;
1084                        p->item->object.flags &= ~STALE;
1085                }
1086        }
1087        num_head = remove_redundant(array, num_head);
1088        for (i = 0; i < num_head; i++)
1089                tail = &commit_list_insert(array[i], tail)->next;
1090        free(array);
1091        return result;
1092}
1093
1094void reduce_heads_replace(struct commit_list **heads)
1095{
1096        struct commit_list *result = reduce_heads(*heads);
1097        free_commit_list(*heads);
1098        *heads = result;
1099}
1100
1101static const char gpg_sig_header[] = "gpgsig";
1102static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1;
1103
1104static int do_sign_commit(struct strbuf *buf, const char *keyid)
1105{
1106        struct strbuf sig = STRBUF_INIT;
1107        int inspos, copypos;
1108        const char *eoh;
1109
1110        /* find the end of the header */
1111        eoh = strstr(buf->buf, "\n\n");
1112        if (!eoh)
1113                inspos = buf->len;
1114        else
1115                inspos = eoh - buf->buf + 1;
1116
1117        if (!keyid || !*keyid)
1118                keyid = get_signing_key();
1119        if (sign_buffer(buf, &sig, keyid)) {
1120                strbuf_release(&sig);
1121                return -1;
1122        }
1123
1124        for (copypos = 0; sig.buf[copypos]; ) {
1125                const char *bol = sig.buf + copypos;
1126                const char *eol = strchrnul(bol, '\n');
1127                int len = (eol - bol) + !!*eol;
1128
1129                if (!copypos) {
1130                        strbuf_insert(buf, inspos, gpg_sig_header, gpg_sig_header_len);
1131                        inspos += gpg_sig_header_len;
1132                }
1133                strbuf_insert(buf, inspos++, " ", 1);
1134                strbuf_insert(buf, inspos, bol, len);
1135                inspos += len;
1136                copypos += len;
1137        }
1138        strbuf_release(&sig);
1139        return 0;
1140}
1141
1142int parse_signed_commit(const struct commit *commit,
1143                        struct strbuf *payload, struct strbuf *signature)
1144{
1145
1146        unsigned long size;
1147        const char *buffer = get_commit_buffer(commit, &size);
1148        int in_signature, saw_signature = -1;
1149        const char *line, *tail;
1150
1151        line = buffer;
1152        tail = buffer + size;
1153        in_signature = 0;
1154        saw_signature = 0;
1155        while (line < tail) {
1156                const char *sig = NULL;
1157                const char *next = memchr(line, '\n', tail - line);
1158
1159                next = next ? next + 1 : tail;
1160                if (in_signature && line[0] == ' ')
1161                        sig = line + 1;
1162                else if (starts_with(line, gpg_sig_header) &&
1163                         line[gpg_sig_header_len] == ' ')
1164                        sig = line + gpg_sig_header_len + 1;
1165                if (sig) {
1166                        strbuf_add(signature, sig, next - sig);
1167                        saw_signature = 1;
1168                        in_signature = 1;
1169                } else {
1170                        if (*line == '\n')
1171                                /* dump the whole remainder of the buffer */
1172                                next = tail;
1173                        strbuf_add(payload, line, next - line);
1174                        in_signature = 0;
1175                }
1176                line = next;
1177        }
1178        unuse_commit_buffer(commit, buffer);
1179        return saw_signature;
1180}
1181
1182int remove_signature(struct strbuf *buf)
1183{
1184        const char *line = buf->buf;
1185        const char *tail = buf->buf + buf->len;
1186        int in_signature = 0;
1187        const char *sig_start = NULL;
1188        const char *sig_end = NULL;
1189
1190        while (line < tail) {
1191                const char *next = memchr(line, '\n', tail - line);
1192                next = next ? next + 1 : tail;
1193
1194                if (in_signature && line[0] == ' ')
1195                        sig_end = next;
1196                else if (starts_with(line, gpg_sig_header) &&
1197                         line[gpg_sig_header_len] == ' ') {
1198                        sig_start = line;
1199                        sig_end = next;
1200                        in_signature = 1;
1201                } else {
1202                        if (*line == '\n')
1203                                /* dump the whole remainder of the buffer */
1204                                next = tail;
1205                        in_signature = 0;
1206                }
1207                line = next;
1208        }
1209
1210        if (sig_start)
1211                strbuf_remove(buf, sig_start - buf->buf, sig_end - sig_start);
1212
1213        return sig_start != NULL;
1214}
1215
1216static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
1217{
1218        struct merge_remote_desc *desc;
1219        struct commit_extra_header *mergetag;
1220        char *buf;
1221        unsigned long size, len;
1222        enum object_type type;
1223
1224        desc = merge_remote_util(parent);
1225        if (!desc || !desc->obj)
1226                return;
1227        buf = read_object_file(&desc->obj->oid, &type, &size);
1228        if (!buf || type != OBJ_TAG)
1229                goto free_return;
1230        len = parse_signature(buf, size);
1231        if (size == len)
1232                goto free_return;
1233        /*
1234         * We could verify this signature and either omit the tag when
1235         * it does not validate, but the integrator may not have the
1236         * public key of the signer of the tag he is merging, while a
1237         * later auditor may have it while auditing, so let's not run
1238         * verify-signed-buffer here for now...
1239         *
1240         * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
1241         *      warn("warning: signed tag unverified.");
1242         */
1243        mergetag = xcalloc(1, sizeof(*mergetag));
1244        mergetag->key = xstrdup("mergetag");
1245        mergetag->value = buf;
1246        mergetag->len = size;
1247
1248        **tail = mergetag;
1249        *tail = &mergetag->next;
1250        return;
1251
1252free_return:
1253        free(buf);
1254}
1255
1256int check_commit_signature(const struct commit *commit, struct signature_check *sigc)
1257{
1258        struct strbuf payload = STRBUF_INIT;
1259        struct strbuf signature = STRBUF_INIT;
1260        int ret = 1;
1261
1262        sigc->result = 'N';
1263
1264        if (parse_signed_commit(commit, &payload, &signature) <= 0)
1265                goto out;
1266        ret = check_signature(payload.buf, payload.len, signature.buf,
1267                signature.len, sigc);
1268
1269 out:
1270        strbuf_release(&payload);
1271        strbuf_release(&signature);
1272
1273        return ret;
1274}
1275
1276
1277
1278void append_merge_tag_headers(struct commit_list *parents,
1279                              struct commit_extra_header ***tail)
1280{
1281        while (parents) {
1282                struct commit *parent = parents->item;
1283                handle_signed_tag(parent, tail);
1284                parents = parents->next;
1285        }
1286}
1287
1288static void add_extra_header(struct strbuf *buffer,
1289                             struct commit_extra_header *extra)
1290{
1291        strbuf_addstr(buffer, extra->key);
1292        if (extra->len)
1293                strbuf_add_lines(buffer, " ", extra->value, extra->len);
1294        else
1295                strbuf_addch(buffer, '\n');
1296}
1297
1298struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
1299                                                      const char **exclude)
1300{
1301        struct commit_extra_header *extra = NULL;
1302        unsigned long size;
1303        const char *buffer = get_commit_buffer(commit, &size);
1304        extra = read_commit_extra_header_lines(buffer, size, exclude);
1305        unuse_commit_buffer(commit, buffer);
1306        return extra;
1307}
1308
1309void for_each_mergetag(each_mergetag_fn fn, struct commit *commit, void *data)
1310{
1311        struct commit_extra_header *extra, *to_free;
1312
1313        to_free = read_commit_extra_headers(commit, NULL);
1314        for (extra = to_free; extra; extra = extra->next) {
1315                if (strcmp(extra->key, "mergetag"))
1316                        continue; /* not a merge tag */
1317                fn(commit, extra, data);
1318        }
1319        free_commit_extra_headers(to_free);
1320}
1321
1322static inline int standard_header_field(const char *field, size_t len)
1323{
1324        return ((len == 4 && !memcmp(field, "tree", 4)) ||
1325                (len == 6 && !memcmp(field, "parent", 6)) ||
1326                (len == 6 && !memcmp(field, "author", 6)) ||
1327                (len == 9 && !memcmp(field, "committer", 9)) ||
1328                (len == 8 && !memcmp(field, "encoding", 8)));
1329}
1330
1331static int excluded_header_field(const char *field, size_t len, const char **exclude)
1332{
1333        if (!exclude)
1334                return 0;
1335
1336        while (*exclude) {
1337                size_t xlen = strlen(*exclude);
1338                if (len == xlen && !memcmp(field, *exclude, xlen))
1339                        return 1;
1340                exclude++;
1341        }
1342        return 0;
1343}
1344
1345static struct commit_extra_header *read_commit_extra_header_lines(
1346        const char *buffer, size_t size,
1347        const char **exclude)
1348{
1349        struct commit_extra_header *extra = NULL, **tail = &extra, *it = NULL;
1350        const char *line, *next, *eof, *eob;
1351        struct strbuf buf = STRBUF_INIT;
1352
1353        for (line = buffer, eob = line + size;
1354             line < eob && *line != '\n';
1355             line = next) {
1356                next = memchr(line, '\n', eob - line);
1357                next = next ? next + 1 : eob;
1358                if (*line == ' ') {
1359                        /* continuation */
1360                        if (it)
1361                                strbuf_add(&buf, line + 1, next - (line + 1));
1362                        continue;
1363                }
1364                if (it)
1365                        it->value = strbuf_detach(&buf, &it->len);
1366                strbuf_reset(&buf);
1367                it = NULL;
1368
1369                eof = memchr(line, ' ', next - line);
1370                if (!eof)
1371                        eof = next;
1372                else if (standard_header_field(line, eof - line) ||
1373                         excluded_header_field(line, eof - line, exclude))
1374                        continue;
1375
1376                it = xcalloc(1, sizeof(*it));
1377                it->key = xmemdupz(line, eof-line);
1378                *tail = it;
1379                tail = &it->next;
1380                if (eof + 1 < next)
1381                        strbuf_add(&buf, eof + 1, next - (eof + 1));
1382        }
1383        if (it)
1384                it->value = strbuf_detach(&buf, &it->len);
1385        return extra;
1386}
1387
1388void free_commit_extra_headers(struct commit_extra_header *extra)
1389{
1390        while (extra) {
1391                struct commit_extra_header *next = extra->next;
1392                free(extra->key);
1393                free(extra->value);
1394                free(extra);
1395                extra = next;
1396        }
1397}
1398
1399int commit_tree(const char *msg, size_t msg_len, const struct object_id *tree,
1400                struct commit_list *parents, struct object_id *ret,
1401                const char *author, const char *sign_commit)
1402{
1403        struct commit_extra_header *extra = NULL, **tail = &extra;
1404        int result;
1405
1406        append_merge_tag_headers(parents, &tail);
1407        result = commit_tree_extended(msg, msg_len, tree, parents, ret,
1408                                      author, sign_commit, extra);
1409        free_commit_extra_headers(extra);
1410        return result;
1411}
1412
1413static int find_invalid_utf8(const char *buf, int len)
1414{
1415        int offset = 0;
1416        static const unsigned int max_codepoint[] = {
1417                0x7f, 0x7ff, 0xffff, 0x10ffff
1418        };
1419
1420        while (len) {
1421                unsigned char c = *buf++;
1422                int bytes, bad_offset;
1423                unsigned int codepoint;
1424                unsigned int min_val, max_val;
1425
1426                len--;
1427                offset++;
1428
1429                /* Simple US-ASCII? No worries. */
1430                if (c < 0x80)
1431                        continue;
1432
1433                bad_offset = offset-1;
1434
1435                /*
1436                 * Count how many more high bits set: that's how
1437                 * many more bytes this sequence should have.
1438                 */
1439                bytes = 0;
1440                while (c & 0x40) {
1441                        c <<= 1;
1442                        bytes++;
1443                }
1444
1445                /*
1446                 * Must be between 1 and 3 more bytes.  Longer sequences result in
1447                 * codepoints beyond U+10FFFF, which are guaranteed never to exist.
1448                 */
1449                if (bytes < 1 || 3 < bytes)
1450                        return bad_offset;
1451
1452                /* Do we *have* that many bytes? */
1453                if (len < bytes)
1454                        return bad_offset;
1455
1456                /*
1457                 * Place the encoded bits at the bottom of the value and compute the
1458                 * valid range.
1459                 */
1460                codepoint = (c & 0x7f) >> bytes;
1461                min_val = max_codepoint[bytes-1] + 1;
1462                max_val = max_codepoint[bytes];
1463
1464                offset += bytes;
1465                len -= bytes;
1466
1467                /* And verify that they are good continuation bytes */
1468                do {
1469                        codepoint <<= 6;
1470                        codepoint |= *buf & 0x3f;
1471                        if ((*buf++ & 0xc0) != 0x80)
1472                                return bad_offset;
1473                } while (--bytes);
1474
1475                /* Reject codepoints that are out of range for the sequence length. */
1476                if (codepoint < min_val || codepoint > max_val)
1477                        return bad_offset;
1478                /* Surrogates are only for UTF-16 and cannot be encoded in UTF-8. */
1479                if ((codepoint & 0x1ff800) == 0xd800)
1480                        return bad_offset;
1481                /* U+xxFFFE and U+xxFFFF are guaranteed non-characters. */
1482                if ((codepoint & 0xfffe) == 0xfffe)
1483                        return bad_offset;
1484                /* So are anything in the range U+FDD0..U+FDEF. */
1485                if (codepoint >= 0xfdd0 && codepoint <= 0xfdef)
1486                        return bad_offset;
1487        }
1488        return -1;
1489}
1490
1491/*
1492 * This verifies that the buffer is in proper utf8 format.
1493 *
1494 * If it isn't, it assumes any non-utf8 characters are Latin1,
1495 * and does the conversion.
1496 */
1497static int verify_utf8(struct strbuf *buf)
1498{
1499        int ok = 1;
1500        long pos = 0;
1501
1502        for (;;) {
1503                int bad;
1504                unsigned char c;
1505                unsigned char replace[2];
1506
1507                bad = find_invalid_utf8(buf->buf + pos, buf->len - pos);
1508                if (bad < 0)
1509                        return ok;
1510                pos += bad;
1511                ok = 0;
1512                c = buf->buf[pos];
1513                strbuf_remove(buf, pos, 1);
1514
1515                /* We know 'c' must be in the range 128-255 */
1516                replace[0] = 0xc0 + (c >> 6);
1517                replace[1] = 0x80 + (c & 0x3f);
1518                strbuf_insert(buf, pos, replace, 2);
1519                pos += 2;
1520        }
1521}
1522
1523static const char commit_utf8_warn[] =
1524N_("Warning: commit message did not conform to UTF-8.\n"
1525   "You may want to amend it after fixing the message, or set the config\n"
1526   "variable i18n.commitencoding to the encoding your project uses.\n");
1527
1528int commit_tree_extended(const char *msg, size_t msg_len,
1529                         const struct object_id *tree,
1530                         struct commit_list *parents, struct object_id *ret,
1531                         const char *author, const char *sign_commit,
1532                         struct commit_extra_header *extra)
1533{
1534        int result;
1535        int encoding_is_utf8;
1536        struct strbuf buffer;
1537
1538        assert_oid_type(tree, OBJ_TREE);
1539
1540        if (memchr(msg, '\0', msg_len))
1541                return error("a NUL byte in commit log message not allowed.");
1542
1543        /* Not having i18n.commitencoding is the same as having utf-8 */
1544        encoding_is_utf8 = is_encoding_utf8(git_commit_encoding);
1545
1546        strbuf_init(&buffer, 8192); /* should avoid reallocs for the headers */
1547        strbuf_addf(&buffer, "tree %s\n", oid_to_hex(tree));
1548
1549        /*
1550         * NOTE! This ordering means that the same exact tree merged with a
1551         * different order of parents will be a _different_ changeset even
1552         * if everything else stays the same.
1553         */
1554        while (parents) {
1555                struct commit *parent = pop_commit(&parents);
1556                strbuf_addf(&buffer, "parent %s\n",
1557                            oid_to_hex(&parent->object.oid));
1558        }
1559
1560        /* Person/date information */
1561        if (!author)
1562                author = git_author_info(IDENT_STRICT);
1563        strbuf_addf(&buffer, "author %s\n", author);
1564        strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_STRICT));
1565        if (!encoding_is_utf8)
1566                strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
1567
1568        while (extra) {
1569                add_extra_header(&buffer, extra);
1570                extra = extra->next;
1571        }
1572        strbuf_addch(&buffer, '\n');
1573
1574        /* And add the comment */
1575        strbuf_add(&buffer, msg, msg_len);
1576
1577        /* And check the encoding */
1578        if (encoding_is_utf8 && !verify_utf8(&buffer))
1579                fprintf(stderr, _(commit_utf8_warn));
1580
1581        if (sign_commit && do_sign_commit(&buffer, sign_commit)) {
1582                result = -1;
1583                goto out;
1584        }
1585
1586        result = write_object_file(buffer.buf, buffer.len, commit_type, ret);
1587out:
1588        strbuf_release(&buffer);
1589        return result;
1590}
1591
1592void set_merge_remote_desc(struct commit *commit,
1593                           const char *name, struct object *obj)
1594{
1595        struct merge_remote_desc *desc;
1596        FLEX_ALLOC_STR(desc, name, name);
1597        desc->obj = obj;
1598        commit->util = desc;
1599}
1600
1601struct commit *get_merge_parent(const char *name)
1602{
1603        struct object *obj;
1604        struct commit *commit;
1605        struct object_id oid;
1606        if (get_oid(name, &oid))
1607                return NULL;
1608        obj = parse_object(&oid);
1609        commit = (struct commit *)peel_to_type(name, 0, obj, OBJ_COMMIT);
1610        if (commit && !commit->util)
1611                set_merge_remote_desc(commit, name, obj);
1612        return commit;
1613}
1614
1615/*
1616 * Append a commit to the end of the commit_list.
1617 *
1618 * next starts by pointing to the variable that holds the head of an
1619 * empty commit_list, and is updated to point to the "next" field of
1620 * the last item on the list as new commits are appended.
1621 *
1622 * Usage example:
1623 *
1624 *     struct commit_list *list;
1625 *     struct commit_list **next = &list;
1626 *
1627 *     next = commit_list_append(c1, next);
1628 *     next = commit_list_append(c2, next);
1629 *     assert(commit_list_count(list) == 2);
1630 *     return list;
1631 */
1632struct commit_list **commit_list_append(struct commit *commit,
1633                                        struct commit_list **next)
1634{
1635        struct commit_list *new_commit = xmalloc(sizeof(struct commit_list));
1636        new_commit->item = commit;
1637        *next = new_commit;
1638        new_commit->next = NULL;
1639        return &new_commit->next;
1640}
1641
1642const char *find_commit_header(const char *msg, const char *key, size_t *out_len)
1643{
1644        int key_len = strlen(key);
1645        const char *line = msg;
1646
1647        while (line) {
1648                const char *eol = strchrnul(line, '\n');
1649
1650                if (line == eol)
1651                        return NULL;
1652
1653                if (eol - line > key_len &&
1654                    !strncmp(line, key, key_len) &&
1655                    line[key_len] == ' ') {
1656                        *out_len = eol - line - key_len - 1;
1657                        return line + key_len + 1;
1658                }
1659                line = *eol ? eol + 1 : NULL;
1660        }
1661        return NULL;
1662}
1663
1664/*
1665 * Inspect the given string and determine the true "end" of the log message, in
1666 * order to find where to put a new Signed-off-by: line.  Ignored are
1667 * trailing comment lines and blank lines.  To support "git commit -s
1668 * --amend" on an existing commit, we also ignore "Conflicts:".  To
1669 * support "git commit -v", we truncate at cut lines.
1670 *
1671 * Returns the number of bytes from the tail to ignore, to be fed as
1672 * the second parameter to append_signoff().
1673 */
1674int ignore_non_trailer(const char *buf, size_t len)
1675{
1676        int boc = 0;
1677        int bol = 0;
1678        int in_old_conflicts_block = 0;
1679        size_t cutoff = wt_status_locate_end(buf, len);
1680
1681        while (bol < cutoff) {
1682                const char *next_line = memchr(buf + bol, '\n', len - bol);
1683
1684                if (!next_line)
1685                        next_line = buf + len;
1686                else
1687                        next_line++;
1688
1689                if (buf[bol] == comment_line_char || buf[bol] == '\n') {
1690                        /* is this the first of the run of comments? */
1691                        if (!boc)
1692                                boc = bol;
1693                        /* otherwise, it is just continuing */
1694                } else if (starts_with(buf + bol, "Conflicts:\n")) {
1695                        in_old_conflicts_block = 1;
1696                        if (!boc)
1697                                boc = bol;
1698                } else if (in_old_conflicts_block && buf[bol] == '\t') {
1699                        ; /* a pathname in the conflicts block */
1700                } else if (boc) {
1701                        /* the previous was not trailing comment */
1702                        boc = 0;
1703                        in_old_conflicts_block = 0;
1704                }
1705                bol = next_line - buf;
1706        }
1707        return boc ? len - boc : len - cutoff;
1708}