revision.con commit git-log --first-parent: show only the first parent log (0053e90)
   1#include "cache.h"
   2#include "tag.h"
   3#include "blob.h"
   4#include "tree.h"
   5#include "commit.h"
   6#include "diff.h"
   7#include "refs.h"
   8#include "revision.h"
   9#include "grep.h"
  10#include "reflog-walk.h"
  11
  12static char *path_name(struct name_path *path, const char *name)
  13{
  14        struct name_path *p;
  15        char *n, *m;
  16        int nlen = strlen(name);
  17        int len = nlen + 1;
  18
  19        for (p = path; p; p = p->up) {
  20                if (p->elem_len)
  21                        len += p->elem_len + 1;
  22        }
  23        n = xmalloc(len);
  24        m = n + len - (nlen + 1);
  25        strcpy(m, name);
  26        for (p = path; p; p = p->up) {
  27                if (p->elem_len) {
  28                        m -= p->elem_len + 1;
  29                        memcpy(m, p->elem, p->elem_len);
  30                        m[p->elem_len] = '/';
  31                }
  32        }
  33        return n;
  34}
  35
  36void add_object(struct object *obj,
  37                struct object_array *p,
  38                struct name_path *path,
  39                const char *name)
  40{
  41        add_object_array(obj, path_name(path, name), p);
  42}
  43
  44static void mark_blob_uninteresting(struct blob *blob)
  45{
  46        if (blob->object.flags & UNINTERESTING)
  47                return;
  48        blob->object.flags |= UNINTERESTING;
  49}
  50
  51void mark_tree_uninteresting(struct tree *tree)
  52{
  53        struct tree_desc desc;
  54        struct name_entry entry;
  55        struct object *obj = &tree->object;
  56
  57        if (obj->flags & UNINTERESTING)
  58                return;
  59        obj->flags |= UNINTERESTING;
  60        if (!has_sha1_file(obj->sha1))
  61                return;
  62        if (parse_tree(tree) < 0)
  63                die("bad tree %s", sha1_to_hex(obj->sha1));
  64
  65        desc.buf = tree->buffer;
  66        desc.size = tree->size;
  67        while (tree_entry(&desc, &entry)) {
  68                if (S_ISDIR(entry.mode))
  69                        mark_tree_uninteresting(lookup_tree(entry.sha1));
  70                else
  71                        mark_blob_uninteresting(lookup_blob(entry.sha1));
  72        }
  73
  74        /*
  75         * We don't care about the tree any more
  76         * after it has been marked uninteresting.
  77         */
  78        free(tree->buffer);
  79        tree->buffer = NULL;
  80}
  81
  82void mark_parents_uninteresting(struct commit *commit)
  83{
  84        struct commit_list *parents = commit->parents;
  85
  86        while (parents) {
  87                struct commit *commit = parents->item;
  88                if (!(commit->object.flags & UNINTERESTING)) {
  89                        commit->object.flags |= UNINTERESTING;
  90
  91                        /*
  92                         * Normally we haven't parsed the parent
  93                         * yet, so we won't have a parent of a parent
  94                         * here. However, it may turn out that we've
  95                         * reached this commit some other way (where it
  96                         * wasn't uninteresting), in which case we need
  97                         * to mark its parents recursively too..
  98                         */
  99                        if (commit->parents)
 100                                mark_parents_uninteresting(commit);
 101                }
 102
 103                /*
 104                 * A missing commit is ok iff its parent is marked
 105                 * uninteresting.
 106                 *
 107                 * We just mark such a thing parsed, so that when
 108                 * it is popped next time around, we won't be trying
 109                 * to parse it and get an error.
 110                 */
 111                if (!has_sha1_file(commit->object.sha1))
 112                        commit->object.parsed = 1;
 113                parents = parents->next;
 114        }
 115}
 116
 117void add_pending_object(struct rev_info *revs, struct object *obj, const char *name)
 118{
 119        if (revs->no_walk && (obj->flags & UNINTERESTING))
 120                die("object ranges do not make sense when not walking revisions");
 121        add_object_array(obj, name, &revs->pending);
 122        if (revs->reflog_info && obj->type == OBJ_COMMIT)
 123                add_reflog_for_walk(revs->reflog_info,
 124                                (struct commit *)obj, name);
 125}
 126
 127static struct object *get_reference(struct rev_info *revs, const char *name, const unsigned char *sha1, unsigned int flags)
 128{
 129        struct object *object;
 130
 131        object = parse_object(sha1);
 132        if (!object)
 133                die("bad object %s", name);
 134        object->flags |= flags;
 135        return object;
 136}
 137
 138static struct commit *handle_commit(struct rev_info *revs, struct object *object, const char *name)
 139{
 140        unsigned long flags = object->flags;
 141
 142        /*
 143         * Tag object? Look what it points to..
 144         */
 145        while (object->type == OBJ_TAG) {
 146                struct tag *tag = (struct tag *) object;
 147                if (revs->tag_objects && !(flags & UNINTERESTING))
 148                        add_pending_object(revs, object, tag->tag);
 149                object = parse_object(tag->tagged->sha1);
 150                if (!object)
 151                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 152        }
 153
 154        /*
 155         * Commit object? Just return it, we'll do all the complex
 156         * reachability crud.
 157         */
 158        if (object->type == OBJ_COMMIT) {
 159                struct commit *commit = (struct commit *)object;
 160                if (parse_commit(commit) < 0)
 161                        die("unable to parse commit %s", name);
 162                if (flags & UNINTERESTING) {
 163                        commit->object.flags |= UNINTERESTING;
 164                        mark_parents_uninteresting(commit);
 165                        revs->limited = 1;
 166                }
 167                return commit;
 168        }
 169
 170        /*
 171         * Tree object? Either mark it uniniteresting, or add it
 172         * to the list of objects to look at later..
 173         */
 174        if (object->type == OBJ_TREE) {
 175                struct tree *tree = (struct tree *)object;
 176                if (!revs->tree_objects)
 177                        return NULL;
 178                if (flags & UNINTERESTING) {
 179                        mark_tree_uninteresting(tree);
 180                        return NULL;
 181                }
 182                add_pending_object(revs, object, "");
 183                return NULL;
 184        }
 185
 186        /*
 187         * Blob object? You know the drill by now..
 188         */
 189        if (object->type == OBJ_BLOB) {
 190                struct blob *blob = (struct blob *)object;
 191                if (!revs->blob_objects)
 192                        return NULL;
 193                if (flags & UNINTERESTING) {
 194                        mark_blob_uninteresting(blob);
 195                        return NULL;
 196                }
 197                add_pending_object(revs, object, "");
 198                return NULL;
 199        }
 200        die("%s is unknown object", name);
 201}
 202
 203static int everybody_uninteresting(struct commit_list *orig)
 204{
 205        struct commit_list *list = orig;
 206        while (list) {
 207                struct commit *commit = list->item;
 208                list = list->next;
 209                if (commit->object.flags & UNINTERESTING)
 210                        continue;
 211                return 0;
 212        }
 213        return 1;
 214}
 215
 216static int tree_difference = REV_TREE_SAME;
 217
 218static void file_add_remove(struct diff_options *options,
 219                    int addremove, unsigned mode,
 220                    const unsigned char *sha1,
 221                    const char *base, const char *path)
 222{
 223        int diff = REV_TREE_DIFFERENT;
 224
 225        /*
 226         * Is it an add of a new file? It means that the old tree
 227         * didn't have it at all, so we will turn "REV_TREE_SAME" ->
 228         * "REV_TREE_NEW", but leave any "REV_TREE_DIFFERENT" alone
 229         * (and if it already was "REV_TREE_NEW", we'll keep it
 230         * "REV_TREE_NEW" of course).
 231         */
 232        if (addremove == '+') {
 233                diff = tree_difference;
 234                if (diff != REV_TREE_SAME)
 235                        return;
 236                diff = REV_TREE_NEW;
 237        }
 238        tree_difference = diff;
 239}
 240
 241static void file_change(struct diff_options *options,
 242                 unsigned old_mode, unsigned new_mode,
 243                 const unsigned char *old_sha1,
 244                 const unsigned char *new_sha1,
 245                 const char *base, const char *path)
 246{
 247        tree_difference = REV_TREE_DIFFERENT;
 248}
 249
 250int rev_compare_tree(struct rev_info *revs, struct tree *t1, struct tree *t2)
 251{
 252        if (!t1)
 253                return REV_TREE_NEW;
 254        if (!t2)
 255                return REV_TREE_DIFFERENT;
 256        tree_difference = REV_TREE_SAME;
 257        if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "",
 258                           &revs->pruning) < 0)
 259                return REV_TREE_DIFFERENT;
 260        return tree_difference;
 261}
 262
 263int rev_same_tree_as_empty(struct rev_info *revs, struct tree *t1)
 264{
 265        int retval;
 266        void *tree;
 267        struct tree_desc empty, real;
 268
 269        if (!t1)
 270                return 0;
 271
 272        tree = read_object_with_reference(t1->object.sha1, tree_type, &real.size, NULL);
 273        if (!tree)
 274                return 0;
 275        real.buf = tree;
 276
 277        empty.buf = "";
 278        empty.size = 0;
 279
 280        tree_difference = 0;
 281        retval = diff_tree(&empty, &real, "", &revs->pruning);
 282        free(tree);
 283
 284        return retval >= 0 && !tree_difference;
 285}
 286
 287static void try_to_simplify_commit(struct rev_info *revs, struct commit *commit)
 288{
 289        struct commit_list **pp, *parent;
 290        int tree_changed = 0, tree_same = 0;
 291
 292        if (!commit->tree)
 293                return;
 294
 295        if (!commit->parents) {
 296                if (!rev_same_tree_as_empty(revs, commit->tree))
 297                        commit->object.flags |= TREECHANGE;
 298                return;
 299        }
 300
 301        pp = &commit->parents;
 302        while ((parent = *pp) != NULL) {
 303                struct commit *p = parent->item;
 304
 305                parse_commit(p);
 306                switch (rev_compare_tree(revs, p->tree, commit->tree)) {
 307                case REV_TREE_SAME:
 308                        tree_same = 1;
 309                        if (!revs->simplify_history || (p->object.flags & UNINTERESTING)) {
 310                                /* Even if a merge with an uninteresting
 311                                 * side branch brought the entire change
 312                                 * we are interested in, we do not want
 313                                 * to lose the other branches of this
 314                                 * merge, so we just keep going.
 315                                 */
 316                                pp = &parent->next;
 317                                continue;
 318                        }
 319                        parent->next = NULL;
 320                        commit->parents = parent;
 321                        return;
 322
 323                case REV_TREE_NEW:
 324                        if (revs->remove_empty_trees &&
 325                            rev_same_tree_as_empty(revs, p->tree)) {
 326                                /* We are adding all the specified
 327                                 * paths from this parent, so the
 328                                 * history beyond this parent is not
 329                                 * interesting.  Remove its parents
 330                                 * (they are grandparents for us).
 331                                 * IOW, we pretend this parent is a
 332                                 * "root" commit.
 333                                 */
 334                                parse_commit(p);
 335                                p->parents = NULL;
 336                        }
 337                /* fallthrough */
 338                case REV_TREE_DIFFERENT:
 339                        tree_changed = 1;
 340                        pp = &parent->next;
 341                        continue;
 342                }
 343                die("bad tree compare for commit %s", sha1_to_hex(commit->object.sha1));
 344        }
 345        if (tree_changed && !tree_same)
 346                commit->object.flags |= TREECHANGE;
 347}
 348
 349static void add_parents_to_list(struct rev_info *revs, struct commit *commit, struct commit_list **list)
 350{
 351        struct commit_list *parent = commit->parents;
 352        unsigned left_flag;
 353        int add, rest;
 354
 355        if (commit->object.flags & ADDED)
 356                return;
 357        commit->object.flags |= ADDED;
 358
 359        /*
 360         * If the commit is uninteresting, don't try to
 361         * prune parents - we want the maximal uninteresting
 362         * set.
 363         *
 364         * Normally we haven't parsed the parent
 365         * yet, so we won't have a parent of a parent
 366         * here. However, it may turn out that we've
 367         * reached this commit some other way (where it
 368         * wasn't uninteresting), in which case we need
 369         * to mark its parents recursively too..
 370         */
 371        if (commit->object.flags & UNINTERESTING) {
 372                while (parent) {
 373                        struct commit *p = parent->item;
 374                        parent = parent->next;
 375                        parse_commit(p);
 376                        p->object.flags |= UNINTERESTING;
 377                        if (p->parents)
 378                                mark_parents_uninteresting(p);
 379                        if (p->object.flags & SEEN)
 380                                continue;
 381                        p->object.flags |= SEEN;
 382                        insert_by_date(p, list);
 383                }
 384                return;
 385        }
 386
 387        /*
 388         * Ok, the commit wasn't uninteresting. Try to
 389         * simplify the commit history and find the parent
 390         * that has no differences in the path set if one exists.
 391         */
 392        if (revs->prune_fn)
 393                revs->prune_fn(revs, commit);
 394
 395        if (revs->no_walk)
 396                return;
 397
 398        left_flag = (commit->object.flags & SYMMETRIC_LEFT);
 399
 400        rest = !revs->first_parent_only;
 401        for (parent = commit->parents, add = 1; parent; add = rest) {
 402                struct commit *p = parent->item;
 403
 404                parent = parent->next;
 405                parse_commit(p);
 406                p->object.flags |= left_flag;
 407                if (p->object.flags & SEEN)
 408                        continue;
 409                p->object.flags |= SEEN;
 410                if (add)
 411                        insert_by_date(p, list);
 412        }
 413}
 414
 415static void limit_list(struct rev_info *revs)
 416{
 417        struct commit_list *list = revs->commits;
 418        struct commit_list *newlist = NULL;
 419        struct commit_list **p = &newlist;
 420
 421        while (list) {
 422                struct commit_list *entry = list;
 423                struct commit *commit = list->item;
 424                struct object *obj = &commit->object;
 425
 426                list = list->next;
 427                free(entry);
 428
 429                if (revs->max_age != -1 && (commit->date < revs->max_age))
 430                        obj->flags |= UNINTERESTING;
 431                add_parents_to_list(revs, commit, &list);
 432                if (obj->flags & UNINTERESTING) {
 433                        mark_parents_uninteresting(commit);
 434                        if (everybody_uninteresting(list))
 435                                break;
 436                        continue;
 437                }
 438                if (revs->min_age != -1 && (commit->date > revs->min_age))
 439                        continue;
 440                p = &commit_list_insert(commit, p)->next;
 441        }
 442        revs->commits = newlist;
 443}
 444
 445struct all_refs_cb {
 446        int all_flags;
 447        int warned_bad_reflog;
 448        struct rev_info *all_revs;
 449        const char *name_for_errormsg;
 450};
 451
 452static int handle_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 453{
 454        struct all_refs_cb *cb = cb_data;
 455        struct object *object = get_reference(cb->all_revs, path, sha1,
 456                                              cb->all_flags);
 457        add_pending_object(cb->all_revs, object, path);
 458        return 0;
 459}
 460
 461static void handle_all(struct rev_info *revs, unsigned flags)
 462{
 463        struct all_refs_cb cb;
 464        cb.all_revs = revs;
 465        cb.all_flags = flags;
 466        for_each_ref(handle_one_ref, &cb);
 467}
 468
 469static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
 470{
 471        struct all_refs_cb *cb = cb_data;
 472        if (!is_null_sha1(sha1)) {
 473                struct object *o = parse_object(sha1);
 474                if (o) {
 475                        o->flags |= cb->all_flags;
 476                        add_pending_object(cb->all_revs, o, "");
 477                }
 478                else if (!cb->warned_bad_reflog) {
 479                        warn("reflog of '%s' references pruned commits",
 480                                cb->name_for_errormsg);
 481                        cb->warned_bad_reflog = 1;
 482                }
 483        }
 484}
 485
 486static int handle_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 487                const char *email, unsigned long timestamp, int tz,
 488                const char *message, void *cb_data)
 489{
 490        handle_one_reflog_commit(osha1, cb_data);
 491        handle_one_reflog_commit(nsha1, cb_data);
 492        return 0;
 493}
 494
 495static int handle_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 496{
 497        struct all_refs_cb *cb = cb_data;
 498        cb->warned_bad_reflog = 0;
 499        cb->name_for_errormsg = path;
 500        for_each_reflog_ent(path, handle_one_reflog_ent, cb_data);
 501        return 0;
 502}
 503
 504static void handle_reflog(struct rev_info *revs, unsigned flags)
 505{
 506        struct all_refs_cb cb;
 507        cb.all_revs = revs;
 508        cb.all_flags = flags;
 509        for_each_reflog(handle_one_reflog, &cb);
 510}
 511
 512static int add_parents_only(struct rev_info *revs, const char *arg, int flags)
 513{
 514        unsigned char sha1[20];
 515        struct object *it;
 516        struct commit *commit;
 517        struct commit_list *parents;
 518
 519        if (*arg == '^') {
 520                flags ^= UNINTERESTING;
 521                arg++;
 522        }
 523        if (get_sha1(arg, sha1))
 524                return 0;
 525        while (1) {
 526                it = get_reference(revs, arg, sha1, 0);
 527                if (it->type != OBJ_TAG)
 528                        break;
 529                hashcpy(sha1, ((struct tag*)it)->tagged->sha1);
 530        }
 531        if (it->type != OBJ_COMMIT)
 532                return 0;
 533        commit = (struct commit *)it;
 534        for (parents = commit->parents; parents; parents = parents->next) {
 535                it = &parents->item->object;
 536                it->flags |= flags;
 537                add_pending_object(revs, it, arg);
 538        }
 539        return 1;
 540}
 541
 542void init_revisions(struct rev_info *revs, const char *prefix)
 543{
 544        memset(revs, 0, sizeof(*revs));
 545
 546        revs->abbrev = DEFAULT_ABBREV;
 547        revs->ignore_merges = 1;
 548        revs->simplify_history = 1;
 549        revs->pruning.recursive = 1;
 550        revs->pruning.add_remove = file_add_remove;
 551        revs->pruning.change = file_change;
 552        revs->lifo = 1;
 553        revs->dense = 1;
 554        revs->prefix = prefix;
 555        revs->max_age = -1;
 556        revs->min_age = -1;
 557        revs->skip_count = -1;
 558        revs->max_count = -1;
 559
 560        revs->prune_fn = NULL;
 561        revs->prune_data = NULL;
 562
 563        revs->topo_setter = topo_sort_default_setter;
 564        revs->topo_getter = topo_sort_default_getter;
 565
 566        revs->commit_format = CMIT_FMT_DEFAULT;
 567
 568        diff_setup(&revs->diffopt);
 569}
 570
 571static void add_pending_commit_list(struct rev_info *revs,
 572                                    struct commit_list *commit_list,
 573                                    unsigned int flags)
 574{
 575        while (commit_list) {
 576                struct object *object = &commit_list->item->object;
 577                object->flags |= flags;
 578                add_pending_object(revs, object, sha1_to_hex(object->sha1));
 579                commit_list = commit_list->next;
 580        }
 581}
 582
 583static void prepare_show_merge(struct rev_info *revs)
 584{
 585        struct commit_list *bases;
 586        struct commit *head, *other;
 587        unsigned char sha1[20];
 588        const char **prune = NULL;
 589        int i, prune_num = 1; /* counting terminating NULL */
 590
 591        if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
 592                die("--merge without HEAD?");
 593        if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
 594                die("--merge without MERGE_HEAD?");
 595        add_pending_object(revs, &head->object, "HEAD");
 596        add_pending_object(revs, &other->object, "MERGE_HEAD");
 597        bases = get_merge_bases(head, other, 1);
 598        while (bases) {
 599                struct commit *it = bases->item;
 600                struct commit_list *n = bases->next;
 601                free(bases);
 602                bases = n;
 603                it->object.flags |= UNINTERESTING;
 604                add_pending_object(revs, &it->object, "(merge-base)");
 605        }
 606
 607        if (!active_nr)
 608                read_cache();
 609        for (i = 0; i < active_nr; i++) {
 610                struct cache_entry *ce = active_cache[i];
 611                if (!ce_stage(ce))
 612                        continue;
 613                if (ce_path_match(ce, revs->prune_data)) {
 614                        prune_num++;
 615                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
 616                        prune[prune_num-2] = ce->name;
 617                        prune[prune_num-1] = NULL;
 618                }
 619                while ((i+1 < active_nr) &&
 620                       ce_same_name(ce, active_cache[i+1]))
 621                        i++;
 622        }
 623        revs->prune_data = prune;
 624}
 625
 626int handle_revision_arg(const char *arg, struct rev_info *revs,
 627                        int flags,
 628                        int cant_be_filename)
 629{
 630        char *dotdot;
 631        struct object *object;
 632        unsigned char sha1[20];
 633        int local_flags;
 634
 635        dotdot = strstr(arg, "..");
 636        if (dotdot) {
 637                unsigned char from_sha1[20];
 638                const char *next = dotdot + 2;
 639                const char *this = arg;
 640                int symmetric = *next == '.';
 641                unsigned int flags_exclude = flags ^ UNINTERESTING;
 642
 643                *dotdot = 0;
 644                next += symmetric;
 645
 646                if (!*next)
 647                        next = "HEAD";
 648                if (dotdot == arg)
 649                        this = "HEAD";
 650                if (!get_sha1(this, from_sha1) &&
 651                    !get_sha1(next, sha1)) {
 652                        struct commit *a, *b;
 653                        struct commit_list *exclude;
 654
 655                        a = lookup_commit_reference(from_sha1);
 656                        b = lookup_commit_reference(sha1);
 657                        if (!a || !b) {
 658                                die(symmetric ?
 659                                    "Invalid symmetric difference expression %s...%s" :
 660                                    "Invalid revision range %s..%s",
 661                                    arg, next);
 662                        }
 663
 664                        if (!cant_be_filename) {
 665                                *dotdot = '.';
 666                                verify_non_filename(revs->prefix, arg);
 667                        }
 668
 669                        if (symmetric) {
 670                                exclude = get_merge_bases(a, b, 1);
 671                                add_pending_commit_list(revs, exclude,
 672                                                        flags_exclude);
 673                                free_commit_list(exclude);
 674                                a->object.flags |= flags | SYMMETRIC_LEFT;
 675                        } else
 676                                a->object.flags |= flags_exclude;
 677                        b->object.flags |= flags;
 678                        add_pending_object(revs, &a->object, this);
 679                        add_pending_object(revs, &b->object, next);
 680                        return 0;
 681                }
 682                *dotdot = '.';
 683        }
 684        dotdot = strstr(arg, "^@");
 685        if (dotdot && !dotdot[2]) {
 686                *dotdot = 0;
 687                if (add_parents_only(revs, arg, flags))
 688                        return 0;
 689                *dotdot = '^';
 690        }
 691        dotdot = strstr(arg, "^!");
 692        if (dotdot && !dotdot[2]) {
 693                *dotdot = 0;
 694                if (!add_parents_only(revs, arg, flags ^ UNINTERESTING))
 695                        *dotdot = '^';
 696        }
 697
 698        local_flags = 0;
 699        if (*arg == '^') {
 700                local_flags = UNINTERESTING;
 701                arg++;
 702        }
 703        if (get_sha1(arg, sha1))
 704                return -1;
 705        if (!cant_be_filename)
 706                verify_non_filename(revs->prefix, arg);
 707        object = get_reference(revs, arg, sha1, flags ^ local_flags);
 708        add_pending_object(revs, object, arg);
 709        return 0;
 710}
 711
 712static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
 713{
 714        if (!revs->grep_filter) {
 715                struct grep_opt *opt = xcalloc(1, sizeof(*opt));
 716                opt->status_only = 1;
 717                opt->pattern_tail = &(opt->pattern_list);
 718                opt->regflags = REG_NEWLINE;
 719                revs->grep_filter = opt;
 720        }
 721        append_grep_pattern(revs->grep_filter, ptn,
 722                            "command line", 0, what);
 723}
 724
 725static void add_header_grep(struct rev_info *revs, const char *field, const char *pattern)
 726{
 727        char *pat;
 728        const char *prefix;
 729        int patlen, fldlen;
 730
 731        fldlen = strlen(field);
 732        patlen = strlen(pattern);
 733        pat = xmalloc(patlen + fldlen + 10);
 734        prefix = ".*";
 735        if (*pattern == '^') {
 736                prefix = "";
 737                pattern++;
 738        }
 739        sprintf(pat, "^%s %s%s", field, prefix, pattern);
 740        add_grep(revs, pat, GREP_PATTERN_HEAD);
 741}
 742
 743static void add_message_grep(struct rev_info *revs, const char *pattern)
 744{
 745        add_grep(revs, pattern, GREP_PATTERN_BODY);
 746}
 747
 748static void add_ignore_packed(struct rev_info *revs, const char *name)
 749{
 750        int num = ++revs->num_ignore_packed;
 751
 752        revs->ignore_packed = xrealloc(revs->ignore_packed,
 753                                       sizeof(const char **) * (num + 1));
 754        revs->ignore_packed[num-1] = name;
 755        revs->ignore_packed[num] = NULL;
 756}
 757
 758/*
 759 * Parse revision information, filling in the "rev_info" structure,
 760 * and removing the used arguments from the argument list.
 761 *
 762 * Returns the number of arguments left that weren't recognized
 763 * (which are also moved to the head of the argument list)
 764 */
 765int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 766{
 767        int i, flags, seen_dashdash, show_merge;
 768        const char **unrecognized = argv + 1;
 769        int left = 1;
 770        int all_match = 0;
 771
 772        /* First, search for "--" */
 773        seen_dashdash = 0;
 774        for (i = 1; i < argc; i++) {
 775                const char *arg = argv[i];
 776                if (strcmp(arg, "--"))
 777                        continue;
 778                argv[i] = NULL;
 779                argc = i;
 780                revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
 781                seen_dashdash = 1;
 782                break;
 783        }
 784
 785        flags = show_merge = 0;
 786        for (i = 1; i < argc; i++) {
 787                const char *arg = argv[i];
 788                if (*arg == '-') {
 789                        int opts;
 790                        if (!prefixcmp(arg, "--max-count=")) {
 791                                revs->max_count = atoi(arg + 12);
 792                                continue;
 793                        }
 794                        if (!prefixcmp(arg, "--skip=")) {
 795                                revs->skip_count = atoi(arg + 7);
 796                                continue;
 797                        }
 798                        /* accept -<digit>, like traditional "head" */
 799                        if ((*arg == '-') && isdigit(arg[1])) {
 800                                revs->max_count = atoi(arg + 1);
 801                                continue;
 802                        }
 803                        if (!strcmp(arg, "-n")) {
 804                                if (argc <= i + 1)
 805                                        die("-n requires an argument");
 806                                revs->max_count = atoi(argv[++i]);
 807                                continue;
 808                        }
 809                        if (!prefixcmp(arg, "-n")) {
 810                                revs->max_count = atoi(arg + 2);
 811                                continue;
 812                        }
 813                        if (!prefixcmp(arg, "--max-age=")) {
 814                                revs->max_age = atoi(arg + 10);
 815                                continue;
 816                        }
 817                        if (!prefixcmp(arg, "--since=")) {
 818                                revs->max_age = approxidate(arg + 8);
 819                                continue;
 820                        }
 821                        if (!prefixcmp(arg, "--after=")) {
 822                                revs->max_age = approxidate(arg + 8);
 823                                continue;
 824                        }
 825                        if (!prefixcmp(arg, "--min-age=")) {
 826                                revs->min_age = atoi(arg + 10);
 827                                continue;
 828                        }
 829                        if (!prefixcmp(arg, "--before=")) {
 830                                revs->min_age = approxidate(arg + 9);
 831                                continue;
 832                        }
 833                        if (!prefixcmp(arg, "--until=")) {
 834                                revs->min_age = approxidate(arg + 8);
 835                                continue;
 836                        }
 837                        if (!strcmp(arg, "--all")) {
 838                                handle_all(revs, flags);
 839                                continue;
 840                        }
 841                        if (!strcmp(arg, "--first-parent")) {
 842                                revs->first_parent_only = 1;
 843                                continue;
 844                        }
 845                        if (!strcmp(arg, "--reflog")) {
 846                                handle_reflog(revs, flags);
 847                                continue;
 848                        }
 849                        if (!strcmp(arg, "-g") ||
 850                                        !strcmp(arg, "--walk-reflogs")) {
 851                                init_reflog_walk(&revs->reflog_info);
 852                                continue;
 853                        }
 854                        if (!strcmp(arg, "--not")) {
 855                                flags ^= UNINTERESTING;
 856                                continue;
 857                        }
 858                        if (!strcmp(arg, "--default")) {
 859                                if (++i >= argc)
 860                                        die("bad --default argument");
 861                                def = argv[i];
 862                                continue;
 863                        }
 864                        if (!strcmp(arg, "--merge")) {
 865                                show_merge = 1;
 866                                continue;
 867                        }
 868                        if (!strcmp(arg, "--topo-order")) {
 869                                revs->topo_order = 1;
 870                                continue;
 871                        }
 872                        if (!strcmp(arg, "--date-order")) {
 873                                revs->lifo = 0;
 874                                revs->topo_order = 1;
 875                                continue;
 876                        }
 877                        if (!strcmp(arg, "--parents")) {
 878                                revs->parents = 1;
 879                                continue;
 880                        }
 881                        if (!strcmp(arg, "--dense")) {
 882                                revs->dense = 1;
 883                                continue;
 884                        }
 885                        if (!strcmp(arg, "--sparse")) {
 886                                revs->dense = 0;
 887                                continue;
 888                        }
 889                        if (!strcmp(arg, "--remove-empty")) {
 890                                revs->remove_empty_trees = 1;
 891                                continue;
 892                        }
 893                        if (!strcmp(arg, "--no-merges")) {
 894                                revs->no_merges = 1;
 895                                continue;
 896                        }
 897                        if (!strcmp(arg, "--boundary")) {
 898                                revs->boundary = 1;
 899                                continue;
 900                        }
 901                        if (!strcmp(arg, "--left-right")) {
 902                                revs->left_right = 1;
 903                                continue;
 904                        }
 905                        if (!strcmp(arg, "--objects")) {
 906                                revs->tag_objects = 1;
 907                                revs->tree_objects = 1;
 908                                revs->blob_objects = 1;
 909                                continue;
 910                        }
 911                        if (!strcmp(arg, "--objects-edge")) {
 912                                revs->tag_objects = 1;
 913                                revs->tree_objects = 1;
 914                                revs->blob_objects = 1;
 915                                revs->edge_hint = 1;
 916                                continue;
 917                        }
 918                        if (!strcmp(arg, "--unpacked")) {
 919                                revs->unpacked = 1;
 920                                free(revs->ignore_packed);
 921                                revs->ignore_packed = NULL;
 922                                revs->num_ignore_packed = 0;
 923                                continue;
 924                        }
 925                        if (!prefixcmp(arg, "--unpacked=")) {
 926                                revs->unpacked = 1;
 927                                add_ignore_packed(revs, arg+11);
 928                                continue;
 929                        }
 930                        if (!strcmp(arg, "-r")) {
 931                                revs->diff = 1;
 932                                revs->diffopt.recursive = 1;
 933                                continue;
 934                        }
 935                        if (!strcmp(arg, "-t")) {
 936                                revs->diff = 1;
 937                                revs->diffopt.recursive = 1;
 938                                revs->diffopt.tree_in_recursive = 1;
 939                                continue;
 940                        }
 941                        if (!strcmp(arg, "-m")) {
 942                                revs->ignore_merges = 0;
 943                                continue;
 944                        }
 945                        if (!strcmp(arg, "-c")) {
 946                                revs->diff = 1;
 947                                revs->dense_combined_merges = 0;
 948                                revs->combine_merges = 1;
 949                                continue;
 950                        }
 951                        if (!strcmp(arg, "--cc")) {
 952                                revs->diff = 1;
 953                                revs->dense_combined_merges = 1;
 954                                revs->combine_merges = 1;
 955                                continue;
 956                        }
 957                        if (!strcmp(arg, "-v")) {
 958                                revs->verbose_header = 1;
 959                                continue;
 960                        }
 961                        if (!prefixcmp(arg, "--pretty")) {
 962                                revs->verbose_header = 1;
 963                                revs->commit_format = get_commit_format(arg+8);
 964                                continue;
 965                        }
 966                        if (!strcmp(arg, "--root")) {
 967                                revs->show_root_diff = 1;
 968                                continue;
 969                        }
 970                        if (!strcmp(arg, "--no-commit-id")) {
 971                                revs->no_commit_id = 1;
 972                                continue;
 973                        }
 974                        if (!strcmp(arg, "--always")) {
 975                                revs->always_show_header = 1;
 976                                continue;
 977                        }
 978                        if (!strcmp(arg, "--no-abbrev")) {
 979                                revs->abbrev = 0;
 980                                continue;
 981                        }
 982                        if (!strcmp(arg, "--abbrev")) {
 983                                revs->abbrev = DEFAULT_ABBREV;
 984                                continue;
 985                        }
 986                        if (!prefixcmp(arg, "--abbrev=")) {
 987                                revs->abbrev = strtoul(arg + 9, NULL, 10);
 988                                if (revs->abbrev < MINIMUM_ABBREV)
 989                                        revs->abbrev = MINIMUM_ABBREV;
 990                                else if (revs->abbrev > 40)
 991                                        revs->abbrev = 40;
 992                                continue;
 993                        }
 994                        if (!strcmp(arg, "--abbrev-commit")) {
 995                                revs->abbrev_commit = 1;
 996                                continue;
 997                        }
 998                        if (!strcmp(arg, "--full-diff")) {
 999                                revs->diff = 1;
1000                                revs->full_diff = 1;
1001                                continue;
1002                        }
1003                        if (!strcmp(arg, "--full-history")) {
1004                                revs->simplify_history = 0;
1005                                continue;
1006                        }
1007                        if (!strcmp(arg, "--relative-date")) {
1008                                revs->relative_date = 1;
1009                                continue;
1010                        }
1011
1012                        /*
1013                         * Grepping the commit log
1014                         */
1015                        if (!prefixcmp(arg, "--author=")) {
1016                                add_header_grep(revs, "author", arg+9);
1017                                continue;
1018                        }
1019                        if (!prefixcmp(arg, "--committer=")) {
1020                                add_header_grep(revs, "committer", arg+12);
1021                                continue;
1022                        }
1023                        if (!prefixcmp(arg, "--grep=")) {
1024                                add_message_grep(revs, arg+7);
1025                                continue;
1026                        }
1027                        if (!strcmp(arg, "--all-match")) {
1028                                all_match = 1;
1029                                continue;
1030                        }
1031                        if (!prefixcmp(arg, "--encoding=")) {
1032                                arg += 11;
1033                                if (strcmp(arg, "none"))
1034                                        git_log_output_encoding = strdup(arg);
1035                                else
1036                                        git_log_output_encoding = "";
1037                                continue;
1038                        }
1039                        if (!strcmp(arg, "--reverse")) {
1040                                revs->reverse ^= 1;
1041                                continue;
1042                        }
1043
1044                        opts = diff_opt_parse(&revs->diffopt, argv+i, argc-i);
1045                        if (opts > 0) {
1046                                revs->diff = 1;
1047                                i += opts - 1;
1048                                continue;
1049                        }
1050                        *unrecognized++ = arg;
1051                        left++;
1052                        continue;
1053                }
1054
1055                if (handle_revision_arg(arg, revs, flags, seen_dashdash)) {
1056                        int j;
1057                        if (seen_dashdash || *arg == '^')
1058                                die("bad revision '%s'", arg);
1059
1060                        /* If we didn't have a "--":
1061                         * (1) all filenames must exist;
1062                         * (2) all rev-args must not be interpretable
1063                         *     as a valid filename.
1064                         * but the latter we have checked in the main loop.
1065                         */
1066                        for (j = i; j < argc; j++)
1067                                verify_filename(revs->prefix, argv[j]);
1068
1069                        revs->prune_data = get_pathspec(revs->prefix,
1070                                                        argv + i);
1071                        break;
1072                }
1073        }
1074
1075        if (show_merge)
1076                prepare_show_merge(revs);
1077        if (def && !revs->pending.nr) {
1078                unsigned char sha1[20];
1079                struct object *object;
1080                if (get_sha1(def, sha1))
1081                        die("bad default revision '%s'", def);
1082                object = get_reference(revs, def, sha1, 0);
1083                add_pending_object(revs, object, def);
1084        }
1085
1086        if (revs->topo_order)
1087                revs->limited = 1;
1088
1089        if (revs->prune_data) {
1090                diff_tree_setup_paths(revs->prune_data, &revs->pruning);
1091                revs->prune_fn = try_to_simplify_commit;
1092                if (!revs->full_diff)
1093                        diff_tree_setup_paths(revs->prune_data, &revs->diffopt);
1094        }
1095        if (revs->combine_merges) {
1096                revs->ignore_merges = 0;
1097                if (revs->dense_combined_merges && !revs->diffopt.output_format)
1098                        revs->diffopt.output_format = DIFF_FORMAT_PATCH;
1099        }
1100        revs->diffopt.abbrev = revs->abbrev;
1101        if (diff_setup_done(&revs->diffopt) < 0)
1102                die("diff_setup_done failed");
1103
1104        if (revs->grep_filter) {
1105                revs->grep_filter->all_match = all_match;
1106                compile_grep_patterns(revs->grep_filter);
1107        }
1108
1109        return left;
1110}
1111
1112void prepare_revision_walk(struct rev_info *revs)
1113{
1114        int nr = revs->pending.nr;
1115        struct object_array_entry *e, *list;
1116
1117        e = list = revs->pending.objects;
1118        revs->pending.nr = 0;
1119        revs->pending.alloc = 0;
1120        revs->pending.objects = NULL;
1121        while (--nr >= 0) {
1122                struct commit *commit = handle_commit(revs, e->item, e->name);
1123                if (commit) {
1124                        if (!(commit->object.flags & SEEN)) {
1125                                commit->object.flags |= SEEN;
1126                                insert_by_date(commit, &revs->commits);
1127                        }
1128                }
1129                e++;
1130        }
1131        free(list);
1132
1133        if (revs->no_walk)
1134                return;
1135        if (revs->limited)
1136                limit_list(revs);
1137        if (revs->topo_order)
1138                sort_in_topological_order_fn(&revs->commits, revs->lifo,
1139                                             revs->topo_setter,
1140                                             revs->topo_getter);
1141}
1142
1143static int rewrite_one(struct rev_info *revs, struct commit **pp)
1144{
1145        for (;;) {
1146                struct commit *p = *pp;
1147                if (!revs->limited)
1148                        add_parents_to_list(revs, p, &revs->commits);
1149                if (p->parents && p->parents->next)
1150                        return 0;
1151                if (p->object.flags & (TREECHANGE | UNINTERESTING))
1152                        return 0;
1153                if (!p->parents)
1154                        return -1;
1155                *pp = p->parents->item;
1156        }
1157}
1158
1159static void rewrite_parents(struct rev_info *revs, struct commit *commit)
1160{
1161        struct commit_list **pp = &commit->parents;
1162        while (*pp) {
1163                struct commit_list *parent = *pp;
1164                if (rewrite_one(revs, &parent->item) < 0) {
1165                        *pp = parent->next;
1166                        continue;
1167                }
1168                pp = &parent->next;
1169        }
1170}
1171
1172static int commit_match(struct commit *commit, struct rev_info *opt)
1173{
1174        if (!opt->grep_filter)
1175                return 1;
1176        return grep_buffer(opt->grep_filter,
1177                           NULL, /* we say nothing, not even filename */
1178                           commit->buffer, strlen(commit->buffer));
1179}
1180
1181static struct commit *get_revision_1(struct rev_info *revs)
1182{
1183        if (!revs->commits)
1184                return NULL;
1185
1186        do {
1187                struct commit_list *entry = revs->commits;
1188                struct commit *commit = entry->item;
1189
1190                revs->commits = entry->next;
1191                free(entry);
1192
1193                if (revs->reflog_info)
1194                        fake_reflog_parent(revs->reflog_info, commit);
1195
1196                /*
1197                 * If we haven't done the list limiting, we need to look at
1198                 * the parents here. We also need to do the date-based limiting
1199                 * that we'd otherwise have done in limit_list().
1200                 */
1201                if (!revs->limited) {
1202                        if (revs->max_age != -1 &&
1203                            (commit->date < revs->max_age))
1204                                continue;
1205                        add_parents_to_list(revs, commit, &revs->commits);
1206                }
1207                if (commit->object.flags & SHOWN)
1208                        continue;
1209
1210                if (revs->unpacked && has_sha1_pack(commit->object.sha1,
1211                                                    revs->ignore_packed))
1212                    continue;
1213
1214                if (commit->object.flags & UNINTERESTING)
1215                        continue;
1216                if (revs->min_age != -1 && (commit->date > revs->min_age))
1217                        continue;
1218                if (revs->no_merges &&
1219                    commit->parents && commit->parents->next)
1220                        continue;
1221                if (!commit_match(commit, revs))
1222                        continue;
1223                if (revs->prune_fn && revs->dense) {
1224                        /* Commit without changes? */
1225                        if (!(commit->object.flags & TREECHANGE)) {
1226                                /* drop merges unless we want parenthood */
1227                                if (!revs->parents)
1228                                        continue;
1229                                /* non-merge - always ignore it */
1230                                if (!commit->parents || !commit->parents->next)
1231                                        continue;
1232                        }
1233                        if (revs->parents)
1234                                rewrite_parents(revs, commit);
1235                }
1236                return commit;
1237        } while (revs->commits);
1238        return NULL;
1239}
1240
1241static void gc_boundary(struct object_array *array)
1242{
1243        unsigned nr = array->nr;
1244        unsigned alloc = array->alloc;
1245        struct object_array_entry *objects = array->objects;
1246
1247        if (alloc <= nr) {
1248                unsigned i, j;
1249                for (i = j = 0; i < nr; i++) {
1250                        if (objects[i].item->flags & SHOWN)
1251                                continue;
1252                        if (i != j)
1253                                objects[j] = objects[i];
1254                        j++;
1255                }
1256                for (i = j; i < nr; i++)
1257                        objects[i].item = NULL;
1258                array->nr = j;
1259        }
1260}
1261
1262struct commit *get_revision(struct rev_info *revs)
1263{
1264        struct commit *c = NULL;
1265        struct commit_list *l;
1266
1267        if (revs->boundary == 2) {
1268                unsigned i;
1269                struct object_array *array = &revs->boundary_commits;
1270                struct object_array_entry *objects = array->objects;
1271                for (i = 0; i < array->nr; i++) {
1272                        c = (struct commit *)(objects[i].item);
1273                        if (!c)
1274                                continue;
1275                        if (!(c->object.flags & CHILD_SHOWN))
1276                                continue;
1277                        if (!(c->object.flags & SHOWN))
1278                                break;
1279                }
1280                if (array->nr <= i)
1281                        return NULL;
1282
1283                c->object.flags |= SHOWN | BOUNDARY;
1284                return c;
1285        }
1286
1287        if (revs->reverse) {
1288                int limit = -1;
1289
1290                if (0 <= revs->max_count) {
1291                        limit = revs->max_count;
1292                        if (0 < revs->skip_count)
1293                                limit += revs->skip_count;
1294                }
1295                l = NULL;
1296                while ((c = get_revision_1(revs))) {
1297                        commit_list_insert(c, &l);
1298                        if ((0 < limit) && !--limit)
1299                                break;
1300                }
1301                revs->commits = l;
1302                revs->reverse = 0;
1303                revs->max_count = -1;
1304                c = NULL;
1305        }
1306
1307        /*
1308         * Now pick up what they want to give us
1309         */
1310        c = get_revision_1(revs);
1311        if (c) {
1312                while (0 < revs->skip_count) {
1313                        revs->skip_count--;
1314                        c = get_revision_1(revs);
1315                        if (!c)
1316                                break;
1317                }
1318        }
1319
1320        /*
1321         * Check the max_count.
1322         */
1323        switch (revs->max_count) {
1324        case -1:
1325                break;
1326        case 0:
1327                c = NULL;
1328                break;
1329        default:
1330                revs->max_count--;
1331        }
1332
1333        if (c)
1334                c->object.flags |= SHOWN;
1335
1336        if (!revs->boundary) {
1337                return c;
1338        }
1339
1340        if (!c) {
1341                /*
1342                 * get_revision_1() runs out the commits, and
1343                 * we are done computing the boundaries.
1344                 * switch to boundary commits output mode.
1345                 */
1346                revs->boundary = 2;
1347                return get_revision(revs);
1348        }
1349
1350        /*
1351         * boundary commits are the commits that are parents of the
1352         * ones we got from get_revision_1() but they themselves are
1353         * not returned from get_revision_1().  Before returning
1354         * 'c', we need to mark its parents that they could be boundaries.
1355         */
1356
1357        for (l = c->parents; l; l = l->next) {
1358                struct object *p;
1359                p = &(l->item->object);
1360                if (p->flags & (CHILD_SHOWN | SHOWN))
1361                        continue;
1362                p->flags |= CHILD_SHOWN;
1363                gc_boundary(&revs->boundary_commits);
1364                add_object_array(p, NULL, &revs->boundary_commits);
1365        }
1366
1367        return c;
1368}