Andrew's git - gitweb.git/blob - builtin/name-rev.c

   1#include "builtin.h"
   2#include "cache.h"
   3#include "repository.h"
   4#include "config.h"
   5#include "commit.h"
   6#include "tag.h"
   7#include "refs.h"
   8#include "parse-options.h"
   9#include "sha1-lookup.h"
  10#include "commit-slab.h"
  11
  12#define CUTOFF_DATE_SLOP 86400 /* one day */
  13
  14typedef struct rev_name {
  15        const char *tip_name;
  16        timestamp_t taggerdate;
  17        int generation;
  18        int distance;
  19        int from_tag;
  20} rev_name;
  21
  22define_commit_slab(commit_rev_name, struct rev_name *);
  23
  24static timestamp_t cutoff = TIME_MAX;
  25static struct commit_rev_name rev_names;
  26
  27/* How many generations are maximally preferred over _one_ merge traversal? */
  28#define MERGE_TRAVERSAL_WEIGHT 65535
  29
  30static struct rev_name *get_commit_rev_name(struct commit *commit)
  31{
  32        struct rev_name **slot = commit_rev_name_peek(&rev_names, commit);
  33
  34        return slot ? *slot : NULL;
  35}
  36
  37static void set_commit_rev_name(struct commit *commit, struct rev_name *name)
  38{
  39        *commit_rev_name_at(&rev_names, commit) = name;
  40}
  41
  42static int is_better_name(struct rev_name *name,
  43                          timestamp_t taggerdate,
  44                          int distance,
  45                          int from_tag)
  46{
  47        /*
  48         * When comparing names based on tags, prefer names
  49         * based on the older tag, even if it is farther away.
  50         */
  51        if (from_tag && name->from_tag)
  52                return (name->taggerdate > taggerdate ||
  53                        (name->taggerdate == taggerdate &&
  54                         name->distance > distance));
  55
  56        /*
  57         * We know that at least one of them is a non-tag at this point.
  58         * favor a tag over a non-tag.
  59         */
  60        if (name->from_tag != from_tag)
  61                return from_tag;
  62
  63        /*
  64         * We are now looking at two non-tags.  Tiebreak to favor
  65         * shorter hops.
  66         */
  67        if (name->distance != distance)
  68                return name->distance > distance;
  69
  70        /* ... or tiebreak to favor older date */
  71        if (name->taggerdate != taggerdate)
  72                return name->taggerdate > taggerdate;
  73
  74        /* keep the current one if we cannot decide */
  75        return 0;
  76}
  77
  78static void name_rev(struct commit *commit,
  79                const char *tip_name, timestamp_t taggerdate,
  80                int generation, int distance, int from_tag,
  81                int deref)
  82{
  83        struct rev_name *name = get_commit_rev_name(commit);
  84        struct commit_list *parents;
  85        int parent_number = 1;
  86        char *to_free = NULL;
  87
  88        parse_commit(commit);
  89
  90        if (commit->date < cutoff)
  91                return;
  92
  93        if (deref) {
  94                tip_name = to_free = xstrfmt("%s^0", tip_name);
  95
  96                if (generation)
  97                        die("generation: %d, but deref?", generation);
  98        }
  99
 100        if (name == NULL) {
 101                name = xmalloc(sizeof(rev_name));
 102                set_commit_rev_name(commit, name);
 103                goto copy_data;
 104        } else if (is_better_name(name, taggerdate, distance, from_tag)) {
 105copy_data:
 106                name->tip_name = tip_name;
 107                name->taggerdate = taggerdate;
 108                name->generation = generation;
 109                name->distance = distance;
 110                name->from_tag = from_tag;
 111        } else {
 112                free(to_free);
 113                return;
 114        }
 115
 116        for (parents = commit->parents;
 117                        parents;
 118                        parents = parents->next, parent_number++) {
 119                if (parent_number > 1) {
 120                        size_t len;
 121                        char *new_name;
 122
 123                        strip_suffix(tip_name, "^0", &len);
 124                        if (generation > 0)
 125                                new_name = xstrfmt("%.*s~%d^%d", (int)len, tip_name,
 126                                                   generation, parent_number);
 127                        else
 128                                new_name = xstrfmt("%.*s^%d", (int)len, tip_name,
 129                                                   parent_number);
 130
 131                        name_rev(parents->item, new_name, taggerdate, 0,
 132                                 distance + MERGE_TRAVERSAL_WEIGHT,
 133                                 from_tag, 0);
 134                } else {
 135                        name_rev(parents->item, tip_name, taggerdate,
 136                                 generation + 1, distance + 1,
 137                                 from_tag, 0);
 138                }
 139        }
 140}
 141
 142static int subpath_matches(const char *path, const char *filter)
 143{
 144        const char *subpath = path;
 145
 146        while (subpath) {
 147                if (!wildmatch(filter, subpath, 0))
 148                        return subpath - path;
 149                subpath = strchr(subpath, '/');
 150                if (subpath)
 151                        subpath++;
 152        }
 153        return -1;
 154}
 155
 156static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
 157{
 158        if (shorten_unambiguous)
 159                refname = shorten_unambiguous_ref(refname, 0);
 160        else if (starts_with(refname, "refs/heads/"))
 161                refname = refname + 11;
 162        else if (starts_with(refname, "refs/"))
 163                refname = refname + 5;
 164        return refname;
 165}
 166
 167struct name_ref_data {
 168        int tags_only;
 169        int name_only;
 170        struct string_list ref_filters;
 171        struct string_list exclude_filters;
 172};
 173
 174static struct tip_table {
 175        struct tip_table_entry {
 176                struct object_id oid;
 177                const char *refname;
 178        } *table;
 179        int nr;
 180        int alloc;
 181        int sorted;
 182} tip_table;
 183
 184static void add_to_tip_table(const struct object_id *oid, const char *refname,
 185                             int shorten_unambiguous)
 186{
 187        refname = name_ref_abbrev(refname, shorten_unambiguous);
 188
 189        ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
 190        oidcpy(&tip_table.table[tip_table.nr].oid, oid);
 191        tip_table.table[tip_table.nr].refname = xstrdup(refname);
 192        tip_table.nr++;
 193        tip_table.sorted = 0;
 194}
 195
 196static int tipcmp(const void *a_, const void *b_)
 197{
 198        const struct tip_table_entry *a = a_, *b = b_;
 199        return oidcmp(&a->oid, &b->oid);
 200}
 201
 202static int name_ref(const char *path, const struct object_id *oid, int flags, void *cb_data)
 203{
 204        struct object *o = parse_object(the_repository, oid);
 205        struct name_ref_data *data = cb_data;
 206        int can_abbreviate_output = data->tags_only && data->name_only;
 207        int deref = 0;
 208        timestamp_t taggerdate = TIME_MAX;
 209
 210        if (data->tags_only && !starts_with(path, "refs/tags/"))
 211                return 0;
 212
 213        if (data->exclude_filters.nr) {
 214                struct string_list_item *item;
 215
 216                for_each_string_list_item(item, &data->exclude_filters) {
 217                        if (subpath_matches(path, item->string) >= 0)
 218                                return 0;
 219                }
 220        }
 221
 222        if (data->ref_filters.nr) {
 223                struct string_list_item *item;
 224                int matched = 0;
 225
 226                /* See if any of the patterns match. */
 227                for_each_string_list_item(item, &data->ref_filters) {
 228                        /*
 229                         * Check all patterns even after finding a match, so
 230                         * that we can see if a match with a subpath exists.
 231                         * When a user asked for 'refs/tags/v*' and 'v1.*',
 232                         * both of which match, the user is showing her
 233                         * willingness to accept a shortened output by having
 234                         * the 'v1.*' in the acceptable refnames, so we
 235                         * shouldn't stop when seeing 'refs/tags/v1.4' matches
 236                         * 'refs/tags/v*'.  We should show it as 'v1.4'.
 237                         */
 238                        switch (subpath_matches(path, item->string)) {
 239                        case -1: /* did not match */
 240                                break;
 241                        case 0: /* matched fully */
 242                                matched = 1;
 243                                break;
 244                        default: /* matched subpath */
 245                                matched = 1;
 246                                can_abbreviate_output = 1;
 247                                break;
 248                        }
 249                }
 250
 251                /* If none of the patterns matched, stop now */
 252                if (!matched)
 253                        return 0;
 254        }
 255
 256        add_to_tip_table(oid, path, can_abbreviate_output);
 257
 258        while (o && o->type == OBJ_TAG) {
 259                struct tag *t = (struct tag *) o;
 260                if (!t->tagged)
 261                        break; /* broken repository */
 262                o = parse_object(the_repository, &t->tagged->oid);
 263                deref = 1;
 264                taggerdate = t->date;
 265        }
 266        if (o && o->type == OBJ_COMMIT) {
 267                struct commit *commit = (struct commit *)o;
 268                int from_tag = starts_with(path, "refs/tags/");
 269
 270                if (taggerdate == TIME_MAX)
 271                        taggerdate = ((struct commit *)o)->date;
 272                path = name_ref_abbrev(path, can_abbreviate_output);
 273                name_rev(commit, xstrdup(path), taggerdate, 0, 0,
 274                         from_tag, deref);
 275        }
 276        return 0;
 277}
 278
 279static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
 280{
 281        struct tip_table_entry *table = table_;
 282        return table[ix].oid.hash;
 283}
 284
 285static const char *get_exact_ref_match(const struct object *o)
 286{
 287        int found;
 288
 289        if (!tip_table.table || !tip_table.nr)
 290                return NULL;
 291
 292        if (!tip_table.sorted) {
 293                QSORT(tip_table.table, tip_table.nr, tipcmp);
 294                tip_table.sorted = 1;
 295        }
 296
 297        found = sha1_pos(o->oid.hash, tip_table.table, tip_table.nr,
 298                         nth_tip_table_ent);
 299        if (0 <= found)
 300                return tip_table.table[found].refname;
 301        return NULL;
 302}
 303
 304/* may return a constant string or use "buf" as scratch space */
 305static const char *get_rev_name(const struct object *o, struct strbuf *buf)
 306{
 307        struct rev_name *n;
 308        struct commit *c;
 309
 310        if (o->type != OBJ_COMMIT)
 311                return get_exact_ref_match(o);
 312        c = (struct commit *) o;
 313        n = get_commit_rev_name(c);
 314        if (!n)
 315                return NULL;
 316
 317        if (!n->generation)
 318                return n->tip_name;
 319        else {
 320                int len = strlen(n->tip_name);
 321                if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 322                        len -= 2;
 323                strbuf_reset(buf);
 324                strbuf_addf(buf, "%.*s~%d", len, n->tip_name, n->generation);
 325                return buf->buf;
 326        }
 327}
 328
 329static void show_name(const struct object *obj,
 330                      const char *caller_name,
 331                      int always, int allow_undefined, int name_only)
 332{
 333        const char *name;
 334        const struct object_id *oid = &obj->oid;
 335        struct strbuf buf = STRBUF_INIT;
 336
 337        if (!name_only)
 338                printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
 339        name = get_rev_name(obj, &buf);
 340        if (name)
 341                printf("%s\n", name);
 342        else if (allow_undefined)
 343                printf("undefined\n");
 344        else if (always)
 345                printf("%s\n", find_unique_abbrev(oid, DEFAULT_ABBREV));
 346        else
 347                die("cannot describe '%s'", oid_to_hex(oid));
 348        strbuf_release(&buf);
 349}
 350
 351static char const * const name_rev_usage[] = {
 352        N_("git name-rev [<options>] <commit>..."),
 353        N_("git name-rev [<options>] --all"),
 354        N_("git name-rev [<options>] --stdin"),
 355        NULL
 356};
 357
 358static void name_rev_line(char *p, struct name_ref_data *data)
 359{
 360        struct strbuf buf = STRBUF_INIT;
 361        int counter = 0;
 362        char *p_start;
 363        const unsigned hexsz = the_hash_algo->hexsz;
 364
 365        for (p_start = p; *p; p++) {
 366#define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 367                if (!ishex(*p))
 368                        counter = 0;
 369                else if (++counter == hexsz &&
 370                         !ishex(*(p+1))) {
 371                        struct object_id oid;
 372                        const char *name = NULL;
 373                        char c = *(p+1);
 374                        int p_len = p - p_start + 1;
 375
 376                        counter = 0;
 377
 378                        *(p+1) = 0;
 379                        if (!get_oid(p - (hexsz - 1), &oid)) {
 380                                struct object *o =
 381                                        lookup_object(the_repository,
 382                                                      oid.hash);
 383                                if (o)
 384                                        name = get_rev_name(o, &buf);
 385                        }
 386                        *(p+1) = c;
 387
 388                        if (!name)
 389                                continue;
 390
 391                        if (data->name_only)
 392                                printf("%.*s%s", p_len - hexsz, p_start, name);
 393                        else
 394                                printf("%.*s (%s)", p_len, p_start, name);
 395                        p_start = p + 1;
 396                }
 397        }
 398
 399        /* flush */
 400        if (p_start != p)
 401                fwrite(p_start, p - p_start, 1, stdout);
 402
 403        strbuf_release(&buf);
 404}
 405
 406int cmd_name_rev(int argc, const char **argv, const char *prefix)
 407{
 408        struct object_array revs = OBJECT_ARRAY_INIT;
 409        int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 410        struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
 411        struct option opts[] = {
 412                OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 413                OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 414                OPT_STRING_LIST(0, "refs", &data.ref_filters, N_("pattern"),
 415                                   N_("only use refs matching <pattern>")),
 416                OPT_STRING_LIST(0, "exclude", &data.exclude_filters, N_("pattern"),
 417                                   N_("ignore refs matching <pattern>")),
 418                OPT_GROUP(""),
 419                OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
 420                OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
 421                OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
 422                OPT_BOOL(0, "always",     &always,
 423                           N_("show abbreviated commit object as fallback")),
 424                {
 425                        /* A Hidden OPT_BOOL */
 426                        OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
 427                        N_("dereference tags in the input (internal use)"),
 428                        PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
 429                },
 430                OPT_END(),
 431        };
 432
 433        init_commit_rev_name(&rev_names);
 434        git_config(git_default_config, NULL);
 435        argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 436        if (all + transform_stdin + !!argc > 1) {
 437                error("Specify either a list, or --all, not both!");
 438                usage_with_options(name_rev_usage, opts);
 439        }
 440        if (all || transform_stdin)
 441                cutoff = 0;
 442
 443        for (; argc; argc--, argv++) {
 444                struct object_id oid;
 445                struct object *object;
 446                struct commit *commit;
 447
 448                if (get_oid(*argv, &oid)) {
 449                        fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 450                                        *argv);
 451                        continue;
 452                }
 453
 454                commit = NULL;
 455                object = parse_object(the_repository, &oid);
 456                if (object) {
 457                        struct object *peeled = deref_tag(the_repository,
 458                                                          object, *argv, 0);
 459                        if (peeled && peeled->type == OBJ_COMMIT)
 460                                commit = (struct commit *)peeled;
 461                }
 462
 463                if (!object) {
 464                        fprintf(stderr, "Could not get object for %s. Skipping.\n",
 465                                        *argv);
 466                        continue;
 467                }
 468
 469                if (commit) {
 470                        if (cutoff > commit->date)
 471                                cutoff = commit->date;
 472                }
 473
 474                if (peel_tag) {
 475                        if (!commit) {
 476                                fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 477                                        *argv);
 478                                continue;
 479                        }
 480                        object = (struct object *)commit;
 481                }
 482                add_object_array(object, *argv, &revs);
 483        }
 484
 485        if (cutoff)
 486                cutoff = cutoff - CUTOFF_DATE_SLOP;
 487        for_each_ref(name_ref, &data);
 488
 489        if (transform_stdin) {
 490                char buffer[2048];
 491
 492                while (!feof(stdin)) {
 493                        char *p = fgets(buffer, sizeof(buffer), stdin);
 494                        if (!p)
 495                                break;
 496                        name_rev_line(p, &data);
 497                }
 498        } else if (all) {
 499                int i, max;
 500
 501                max = get_max_object_index();
 502                for (i = 0; i < max; i++) {
 503                        struct object *obj = get_indexed_object(i);
 504                        if (!obj || obj->type != OBJ_COMMIT)
 505                                continue;
 506                        show_name(obj, NULL,
 507                                  always, allow_undefined, data.name_only);
 508                }
 509        } else {
 510                int i;
 511                for (i = 0; i < revs.nr; i++)
 512                        show_name(revs.objects[i].item, revs.objects[i].name,
 513                                  always, allow_undefined, data.name_only);
 514        }
 515
 516        UNLEAK(revs);
 517        return 0;
 518}