rev-list.con commit Reduce memory usage in git-update-server-info. (f22ca7c)
   1#include "cache.h"
   2#include "refs.h"
   3#include "tag.h"
   4#include "commit.h"
   5#include "tree.h"
   6#include "blob.h"
   7#include "epoch.h"
   8
   9#define SEEN            (1u << 0)
  10#define INTERESTING     (1u << 1)
  11#define COUNTED         (1u << 2)
  12#define SHOWN           (1u << 3)
  13
  14static const char rev_list_usage[] =
  15        "git-rev-list [OPTION] commit-id <commit-id>\n"
  16                      "  --max-count=nr\n"
  17                      "  --max-age=epoch\n"
  18                      "  --min-age=epoch\n"
  19                      "  --parents\n"
  20                      "  --bisect\n"
  21                      "  --objects\n"
  22                      "  --unpacked\n"
  23                      "  --header\n"
  24                      "  --pretty\n"
  25                      "  --no-merges\n"
  26                      "  --merge-order [ --show-breaks ]\n"
  27                      "  --topo-order";
  28
  29static int unpacked = 0;
  30static int bisect_list = 0;
  31static int tag_objects = 0;
  32static int tree_objects = 0;
  33static int blob_objects = 0;
  34static int verbose_header = 0;
  35static int show_parents = 0;
  36static int hdr_termination = 0;
  37static const char *commit_prefix = "";
  38static unsigned long max_age = -1;
  39static unsigned long min_age = -1;
  40static int max_count = -1;
  41static enum cmit_fmt commit_format = CMIT_FMT_RAW;
  42static int merge_order = 0;
  43static int show_breaks = 0;
  44static int stop_traversal = 0;
  45static int topo_order = 0;
  46static int no_merges = 0;
  47
  48static void show_commit(struct commit *commit)
  49{
  50        commit->object.flags |= SHOWN;
  51        if (show_breaks) {
  52                commit_prefix = "| ";
  53                if (commit->object.flags & DISCONTINUITY) {
  54                        commit_prefix = "^ ";     
  55                } else if (commit->object.flags & BOUNDARY) {
  56                        commit_prefix = "= ";
  57                } 
  58        }                       
  59        printf("%s%s", commit_prefix, sha1_to_hex(commit->object.sha1));
  60        if (show_parents) {
  61                struct commit_list *parents = commit->parents;
  62                while (parents) {
  63                        printf(" %s", sha1_to_hex(parents->item->object.sha1));
  64                        parents = parents->next;
  65                }
  66        }
  67        if (commit_format == CMIT_FMT_ONELINE)
  68                putchar(' ');
  69        else
  70                putchar('\n');
  71
  72        if (verbose_header) {
  73                static char pretty_header[16384];
  74                pretty_print_commit(commit_format, commit->buffer, ~0, pretty_header, sizeof(pretty_header));
  75                printf("%s%c", pretty_header, hdr_termination);
  76        }
  77        fflush(stdout);
  78}
  79
  80static int filter_commit(struct commit * commit)
  81{
  82        if (stop_traversal && (commit->object.flags & BOUNDARY))
  83                return STOP;
  84        if (commit->object.flags & (UNINTERESTING|SHOWN))
  85                return CONTINUE;
  86        if (min_age != -1 && (commit->date > min_age))
  87                return CONTINUE;
  88        if (max_age != -1 && (commit->date < max_age)) {
  89                stop_traversal=1;
  90                return CONTINUE;
  91        }
  92        if (max_count != -1 && !max_count--)
  93                return STOP;
  94        if (no_merges && (commit->parents && commit->parents->next))
  95                return CONTINUE;
  96        return DO;
  97}
  98
  99static int process_commit(struct commit * commit)
 100{
 101        int action=filter_commit(commit);
 102
 103        if (action == STOP) {
 104                return STOP;
 105        }
 106
 107        if (action == CONTINUE) {
 108                return CONTINUE;
 109        }
 110
 111        show_commit(commit);
 112
 113        return CONTINUE;
 114}
 115
 116static struct object_list **add_object(struct object *obj, struct object_list **p, const char *name)
 117{
 118        struct object_list *entry = xmalloc(sizeof(*entry));
 119        entry->item = obj;
 120        entry->next = *p;
 121        entry->name = name;
 122        *p = entry;
 123        return &entry->next;
 124}
 125
 126static struct object_list **process_blob(struct blob *blob, struct object_list **p, const char *name)
 127{
 128        struct object *obj = &blob->object;
 129
 130        if (!blob_objects)
 131                return p;
 132        if (obj->flags & (UNINTERESTING | SEEN))
 133                return p;
 134        obj->flags |= SEEN;
 135        return add_object(obj, p, name);
 136}
 137
 138static struct object_list **process_tree(struct tree *tree, struct object_list **p, const char *name)
 139{
 140        struct object *obj = &tree->object;
 141        struct tree_entry_list *entry;
 142
 143        if (!tree_objects)
 144                return p;
 145        if (obj->flags & (UNINTERESTING | SEEN))
 146                return p;
 147        if (parse_tree(tree) < 0)
 148                die("bad tree object %s", sha1_to_hex(obj->sha1));
 149        obj->flags |= SEEN;
 150        p = add_object(obj, p, name);
 151        entry = tree->entries;
 152        tree->entries = NULL;
 153        while (entry) {
 154                struct tree_entry_list *next = entry->next;
 155                if (entry->directory)
 156                        p = process_tree(entry->item.tree, p, entry->name);
 157                else
 158                        p = process_blob(entry->item.blob, p, entry->name);
 159                free(entry);
 160                entry = next;
 161        }
 162        return p;
 163}
 164
 165static struct object_list *pending_objects = NULL;
 166
 167static void show_commit_list(struct commit_list *list)
 168{
 169        struct object_list *objects = NULL, **p = &objects, *pending;
 170        while (list) {
 171                struct commit *commit = pop_most_recent_commit(&list, SEEN);
 172
 173                p = process_tree(commit->tree, p, "");
 174                if (process_commit(commit) == STOP)
 175                        break;
 176        }
 177        for (pending = pending_objects; pending; pending = pending->next) {
 178                struct object *obj = pending->item;
 179                const char *name = pending->name;
 180                if (obj->flags & (UNINTERESTING | SEEN))
 181                        continue;
 182                if (obj->type == tag_type) {
 183                        obj->flags |= SEEN;
 184                        p = add_object(obj, p, name);
 185                        continue;
 186                }
 187                if (obj->type == tree_type) {
 188                        p = process_tree((struct tree *)obj, p, name);
 189                        continue;
 190                }
 191                if (obj->type == blob_type) {
 192                        p = process_blob((struct blob *)obj, p, name);
 193                        continue;
 194                }
 195                die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 196        }
 197        while (objects) {
 198                /* An object with name "foo\n0000000000000000000000000000000000000000"
 199                 * can be used confuse downstream git-pack-objects very badly.
 200                 */
 201                const char *ep = strchr(objects->name, '\n');
 202                if (ep) {
 203                        printf("%s %.*s\n", sha1_to_hex(objects->item->sha1),
 204                               (int) (ep - objects->name),
 205                               objects->name);
 206                }
 207                else
 208                        printf("%s %s\n", sha1_to_hex(objects->item->sha1), objects->name);
 209                objects = objects->next;
 210        }
 211}
 212
 213static void mark_blob_uninteresting(struct blob *blob)
 214{
 215        if (!blob_objects)
 216                return;
 217        if (blob->object.flags & UNINTERESTING)
 218                return;
 219        blob->object.flags |= UNINTERESTING;
 220}
 221
 222static void mark_tree_uninteresting(struct tree *tree)
 223{
 224        struct object *obj = &tree->object;
 225        struct tree_entry_list *entry;
 226
 227        if (!tree_objects)
 228                return;
 229        if (obj->flags & UNINTERESTING)
 230                return;
 231        obj->flags |= UNINTERESTING;
 232        if (!has_sha1_file(obj->sha1))
 233                return;
 234        if (parse_tree(tree) < 0)
 235                die("bad tree %s", sha1_to_hex(obj->sha1));
 236        entry = tree->entries;
 237        tree->entries = NULL;
 238        while (entry) {
 239                struct tree_entry_list *next = entry->next;
 240                if (entry->directory)
 241                        mark_tree_uninteresting(entry->item.tree);
 242                else
 243                        mark_blob_uninteresting(entry->item.blob);
 244                free(entry);
 245                entry = next;
 246        }
 247}
 248
 249static void mark_parents_uninteresting(struct commit *commit)
 250{
 251        struct commit_list *parents = commit->parents;
 252
 253        while (parents) {
 254                struct commit *commit = parents->item;
 255                commit->object.flags |= UNINTERESTING;
 256
 257                /*
 258                 * Normally we haven't parsed the parent
 259                 * yet, so we won't have a parent of a parent
 260                 * here. However, it may turn out that we've
 261                 * reached this commit some other way (where it
 262                 * wasn't uninteresting), in which case we need
 263                 * to mark its parents recursively too..
 264                 */
 265                if (commit->parents)
 266                        mark_parents_uninteresting(commit);
 267
 268                /*
 269                 * A missing commit is ok iff its parent is marked 
 270                 * uninteresting.
 271                 *
 272                 * We just mark such a thing parsed, so that when
 273                 * it is popped next time around, we won't be trying
 274                 * to parse it and get an error.
 275                 */
 276                if (!has_sha1_file(commit->object.sha1))
 277                        commit->object.parsed = 1;
 278                parents = parents->next;
 279        }
 280}
 281
 282static int everybody_uninteresting(struct commit_list *orig)
 283{
 284        struct commit_list *list = orig;
 285        while (list) {
 286                struct commit *commit = list->item;
 287                list = list->next;
 288                if (commit->object.flags & UNINTERESTING)
 289                        continue;
 290                return 0;
 291        }
 292        return 1;
 293}
 294
 295/*
 296 * This is a truly stupid algorithm, but it's only
 297 * used for bisection, and we just don't care enough.
 298 *
 299 * We care just barely enough to avoid recursing for
 300 * non-merge entries.
 301 */
 302static int count_distance(struct commit_list *entry)
 303{
 304        int nr = 0;
 305
 306        while (entry) {
 307                struct commit *commit = entry->item;
 308                struct commit_list *p;
 309
 310                if (commit->object.flags & (UNINTERESTING | COUNTED))
 311                        break;
 312                nr++;
 313                commit->object.flags |= COUNTED;
 314                p = commit->parents;
 315                entry = p;
 316                if (p) {
 317                        p = p->next;
 318                        while (p) {
 319                                nr += count_distance(p);
 320                                p = p->next;
 321                        }
 322                }
 323        }
 324        return nr;
 325}
 326
 327static void clear_distance(struct commit_list *list)
 328{
 329        while (list) {
 330                struct commit *commit = list->item;
 331                commit->object.flags &= ~COUNTED;
 332                list = list->next;
 333        }
 334}
 335
 336static struct commit_list *find_bisection(struct commit_list *list)
 337{
 338        int nr, closest;
 339        struct commit_list *p, *best;
 340
 341        nr = 0;
 342        p = list;
 343        while (p) {
 344                nr++;
 345                p = p->next;
 346        }
 347        closest = 0;
 348        best = list;
 349
 350        p = list;
 351        while (p) {
 352                int distance = count_distance(p);
 353                clear_distance(list);
 354                if (nr - distance < distance)
 355                        distance = nr - distance;
 356                if (distance > closest) {
 357                        best = p;
 358                        closest = distance;
 359                }
 360                p = p->next;
 361        }
 362        if (best)
 363                best->next = NULL;
 364        return best;
 365}
 366
 367static void mark_edges_uninteresting(struct commit_list *list)
 368{
 369        for ( ; list; list = list->next) {
 370                struct commit_list *parents = list->item->parents;
 371
 372                for ( ; parents; parents = parents->next) {
 373                        struct commit *commit = parents->item;
 374                        if (commit->object.flags & UNINTERESTING)
 375                                mark_tree_uninteresting(commit->tree);
 376                }
 377        }
 378}
 379
 380static struct commit_list *limit_list(struct commit_list *list)
 381{
 382        struct commit_list *newlist = NULL;
 383        struct commit_list **p = &newlist;
 384        while (list) {
 385                struct commit *commit = pop_most_recent_commit(&list, SEEN);
 386                struct object *obj = &commit->object;
 387
 388                if (max_age != -1 && (commit->date < max_age))
 389                        obj->flags |= UNINTERESTING;
 390                if (unpacked && has_sha1_pack(obj->sha1))
 391                        obj->flags |= UNINTERESTING;
 392                if (obj->flags & UNINTERESTING) {
 393                        mark_parents_uninteresting(commit);
 394                        if (everybody_uninteresting(list))
 395                                break;
 396                        continue;
 397                }
 398                if (min_age != -1 && (commit->date > min_age))
 399                        continue;
 400                p = &commit_list_insert(commit, p)->next;
 401        }
 402        if (tree_objects)
 403                mark_edges_uninteresting(newlist);
 404        if (bisect_list)
 405                newlist = find_bisection(newlist);
 406        return newlist;
 407}
 408
 409static void add_pending_object(struct object *obj, const char *name)
 410{
 411        add_object(obj, &pending_objects, name);
 412}
 413
 414static struct commit *get_commit_reference(const char *name, unsigned int flags)
 415{
 416        unsigned char sha1[20];
 417        struct object *object;
 418
 419        if (get_sha1(name, sha1))
 420                usage(rev_list_usage);
 421        object = parse_object(sha1);
 422        if (!object)
 423                die("bad object %s", name);
 424
 425        /*
 426         * Tag object? Look what it points to..
 427         */
 428        while (object->type == tag_type) {
 429                struct tag *tag = (struct tag *) object;
 430                object->flags |= flags;
 431                if (tag_objects && !(object->flags & UNINTERESTING))
 432                        add_pending_object(object, tag->tag);
 433                object = parse_object(tag->tagged->sha1);
 434                if (!object)
 435                        die("bad object %s", sha1_to_hex(tag->tagged->sha1));
 436        }
 437
 438        /*
 439         * Commit object? Just return it, we'll do all the complex
 440         * reachability crud.
 441         */
 442        if (object->type == commit_type) {
 443                struct commit *commit = (struct commit *)object;
 444                object->flags |= flags;
 445                if (parse_commit(commit) < 0)
 446                        die("unable to parse commit %s", name);
 447                if (flags & UNINTERESTING)
 448                        mark_parents_uninteresting(commit);
 449                return commit;
 450        }
 451
 452        /*
 453         * Tree object? Either mark it uniniteresting, or add it
 454         * to the list of objects to look at later..
 455         */
 456        if (object->type == tree_type) {
 457                struct tree *tree = (struct tree *)object;
 458                if (!tree_objects)
 459                        return NULL;
 460                if (flags & UNINTERESTING) {
 461                        mark_tree_uninteresting(tree);
 462                        return NULL;
 463                }
 464                add_pending_object(object, "");
 465                return NULL;
 466        }
 467
 468        /*
 469         * Blob object? You know the drill by now..
 470         */
 471        if (object->type == blob_type) {
 472                struct blob *blob = (struct blob *)object;
 473                if (!blob_objects)
 474                        return NULL;
 475                if (flags & UNINTERESTING) {
 476                        mark_blob_uninteresting(blob);
 477                        return NULL;
 478                }
 479                add_pending_object(object, "");
 480                return NULL;
 481        }
 482        die("%s is unknown object", name);
 483}
 484
 485static void handle_one_commit(struct commit *com, struct commit_list **lst)
 486{
 487        if (!com || com->object.flags & SEEN)
 488                return;
 489        com->object.flags |= SEEN;
 490        commit_list_insert(com, lst);
 491}
 492
 493/* for_each_ref() callback does not allow user data -- Yuck. */
 494static struct commit_list **global_lst;
 495
 496static int include_one_commit(const char *path, const unsigned char *sha1)
 497{
 498        struct commit *com = get_commit_reference(path, 0);
 499        handle_one_commit(com, global_lst);
 500        return 0;
 501}
 502
 503static void handle_all(struct commit_list **lst)
 504{
 505        global_lst = lst;
 506        for_each_ref(include_one_commit);
 507        global_lst = NULL;
 508}
 509
 510int main(int argc, char **argv)
 511{
 512        struct commit_list *list = NULL;
 513        int i, limited = 0;
 514
 515        setup_git_directory();
 516        for (i = 1 ; i < argc; i++) {
 517                int flags;
 518                char *arg = argv[i];
 519                char *dotdot;
 520                struct commit *commit;
 521
 522                if (!strncmp(arg, "--max-count=", 12)) {
 523                        max_count = atoi(arg + 12);
 524                        continue;
 525                }
 526                if (!strncmp(arg, "--max-age=", 10)) {
 527                        max_age = atoi(arg + 10);
 528                        limited = 1;
 529                        continue;
 530                }
 531                if (!strncmp(arg, "--min-age=", 10)) {
 532                        min_age = atoi(arg + 10);
 533                        limited = 1;
 534                        continue;
 535                }
 536                if (!strcmp(arg, "--header")) {
 537                        verbose_header = 1;
 538                        continue;
 539                }
 540                if (!strncmp(arg, "--pretty", 8)) {
 541                        commit_format = get_commit_format(arg+8);
 542                        verbose_header = 1;
 543                        hdr_termination = '\n';
 544                        if (commit_format == CMIT_FMT_ONELINE)
 545                                commit_prefix = "";
 546                        else
 547                                commit_prefix = "commit ";
 548                        continue;
 549                }
 550                if (!strncmp(arg, "--no-merges", 11)) {
 551                        no_merges = 1;
 552                        continue;
 553                }
 554                if (!strcmp(arg, "--parents")) {
 555                        show_parents = 1;
 556                        continue;
 557                }
 558                if (!strcmp(arg, "--bisect")) {
 559                        bisect_list = 1;
 560                        continue;
 561                }
 562                if (!strcmp(arg, "--all")) {
 563                        handle_all(&list);
 564                        continue;
 565                }
 566                if (!strcmp(arg, "--objects")) {
 567                        tag_objects = 1;
 568                        tree_objects = 1;
 569                        blob_objects = 1;
 570                        continue;
 571                }
 572                if (!strcmp(arg, "--unpacked")) {
 573                        unpacked = 1;
 574                        limited = 1;
 575                        continue;
 576                }
 577                if (!strcmp(arg, "--merge-order")) {
 578                        merge_order = 1;
 579                        continue;
 580                }
 581                if (!strcmp(arg, "--show-breaks")) {
 582                        show_breaks = 1;
 583                        continue;
 584                }
 585                if (!strcmp(arg, "--topo-order")) {
 586                        topo_order = 1;
 587                        limited = 1;
 588                        continue;
 589                }
 590
 591                if (show_breaks && !merge_order)
 592                        usage(rev_list_usage);
 593
 594                flags = 0;
 595                dotdot = strstr(arg, "..");
 596                if (dotdot) {
 597                        char *next = dotdot + 2;
 598                        struct commit *exclude = NULL;
 599                        struct commit *include = NULL;
 600                        *dotdot = 0;
 601                        if (!*next)
 602                                next = "HEAD";
 603                        exclude = get_commit_reference(arg, UNINTERESTING);
 604                        include = get_commit_reference(next, 0);
 605                        if (exclude && include) {
 606                                limited = 1;
 607                                handle_one_commit(exclude, &list);
 608                                handle_one_commit(include, &list);
 609                                continue;
 610                        }
 611                        *dotdot = '.';
 612                }
 613                if (*arg == '^') {
 614                        flags = UNINTERESTING;
 615                        arg++;
 616                        limited = 1;
 617                }
 618                commit = get_commit_reference(arg, flags);
 619                handle_one_commit(commit, &list);
 620        }
 621
 622        save_commit_buffer = verbose_header;
 623        track_object_refs = 0;
 624
 625        if (!merge_order) {             
 626                sort_by_date(&list);
 627                if (limited)
 628                        list = limit_list(list);
 629                if (topo_order)
 630                        sort_in_topological_order(&list);
 631                show_commit_list(list);
 632        } else {
 633#ifndef NO_OPENSSL
 634                if (sort_list_in_merge_order(list, &process_commit)) {
 635                        die("merge order sort failed\n");
 636                }
 637#else
 638                die("merge order sort unsupported, OpenSSL not linked");
 639#endif
 640        }
 641
 642        return 0;
 643}