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
  14 typedef 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
  22 define_commit_slab(commit_rev_name, struct rev_name *);
  23
  24 static timestamp_t cutoff = TIME_MAX;
  25 static 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
  30 static 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
  37 static void set_commit_rev_name(struct commit *commit, struct rev_name *name)
  38 {
  39         *commit_rev_name_at(&rev_names, commit) = name;
  40 }
  41
  42 static 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
  78 static 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)) {
 105 copy_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
 142 static 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
 156 static 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
 167 struct 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
 174 static 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
 184 static 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
 196 static 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
 202 static 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
 279 static 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
 285 static 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 */
 305 static 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
 329 static 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
 351 static 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
 358 static 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, &oid);
 382                                 if (o)
 383                                         name = get_rev_name(o, &buf);
 384                         }
 385                         *(p+1) = c;
 386
 387                         if (!name)
 388                                 continue;
 389
 390                         if (data->name_only)
 391                                 printf("%.*s%s", p_len - hexsz, p_start, name);
 392                         else
 393                                 printf("%.*s (%s)", p_len, p_start, name);
 394                         p_start = p + 1;
 395                 }
 396         }
 397
 398         /* flush */
 399         if (p_start != p)
 400                 fwrite(p_start, p - p_start, 1, stdout);
 401
 402         strbuf_release(&buf);
 403 }
 404
 405 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 406 {
 407         struct object_array revs = OBJECT_ARRAY_INIT;
 408         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 409         struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
 410         struct option opts[] = {
 411                 OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 412                 OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 413                 OPT_STRING_LIST(0, "refs", &data.ref_filters, N_("pattern"),
 414                                    N_("only use refs matching <pattern>")),
 415                 OPT_STRING_LIST(0, "exclude", &data.exclude_filters, N_("pattern"),
 416                                    N_("ignore refs matching <pattern>")),
 417                 OPT_GROUP(""),
 418                 OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
 419                 OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
 420                 OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
 421                 OPT_BOOL(0, "always",     &always,
 422                            N_("show abbreviated commit object as fallback")),
 423                 {
 424                         /* A Hidden OPT_BOOL */
 425                         OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
 426                         N_("dereference tags in the input (internal use)"),
 427                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
 428                 },
 429                 OPT_END(),
 430         };
 431
 432         init_commit_rev_name(&rev_names);
 433         git_config(git_default_config, NULL);
 434         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 435         if (all + transform_stdin + !!argc > 1) {
 436                 error("Specify either a list, or --all, not both!");
 437                 usage_with_options(name_rev_usage, opts);
 438         }
 439         if (all || transform_stdin)
 440                 cutoff = 0;
 441
 442         for (; argc; argc--, argv++) {
 443                 struct object_id oid;
 444                 struct object *object;
 445                 struct commit *commit;
 446
 447                 if (get_oid(*argv, &oid)) {
 448                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 449                                         *argv);
 450                         continue;
 451                 }
 452
 453                 commit = NULL;
 454                 object = parse_object(the_repository, &oid);
 455                 if (object) {
 456                         struct object *peeled = deref_tag(the_repository,
 457                                                           object, *argv, 0);
 458                         if (peeled && peeled->type == OBJ_COMMIT)
 459                                 commit = (struct commit *)peeled;
 460                 }
 461
 462                 if (!object) {
 463                         fprintf(stderr, "Could not get object for %s. Skipping.\n",
 464                                         *argv);
 465                         continue;
 466                 }
 467
 468                 if (commit) {
 469                         if (cutoff > commit->date)
 470                                 cutoff = commit->date;
 471                 }
 472
 473                 if (peel_tag) {
 474                         if (!commit) {
 475                                 fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 476                                         *argv);
 477                                 continue;
 478                         }
 479                         object = (struct object *)commit;
 480                 }
 481                 add_object_array(object, *argv, &revs);
 482         }
 483
 484         if (cutoff)
 485                 cutoff = cutoff - CUTOFF_DATE_SLOP;
 486         for_each_ref(name_ref, &data);
 487
 488         if (transform_stdin) {
 489                 char buffer[2048];
 490
 491                 while (!feof(stdin)) {
 492                         char *p = fgets(buffer, sizeof(buffer), stdin);
 493                         if (!p)
 494                                 break;
 495                         name_rev_line(p, &data);
 496                 }
 497         } else if (all) {
 498                 int i, max;
 499
 500                 max = get_max_object_index();
 501                 for (i = 0; i < max; i++) {
 502                         struct object *obj = get_indexed_object(i);
 503                         if (!obj || obj->type != OBJ_COMMIT)
 504                                 continue;
 505                         show_name(obj, NULL,
 506                                   always, allow_undefined, data.name_only);
 507                 }
 508         } else {
 509                 int i;
 510                 for (i = 0; i < revs.nr; i++)
 511                         show_name(revs.objects[i].item, revs.objects[i].name,
 512                                   always, allow_undefined, data.name_only);
 513         }
 514
 515         UNLEAK(revs);
 516         return 0;
 517 }