builtin/name-rev.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "commit.h"
   4 #include "tag.h"
   5 #include "refs.h"
   6 #include "parse-options.h"
   7 #include "sha1-lookup.h"
   8
   9 #define CUTOFF_DATE_SLOP 86400 /* one day */
  10
  11 typedef struct rev_name {
  12         const char *tip_name;
  13         unsigned long taggerdate;
  14         int generation;
  15         int distance;
  16 } rev_name;
  17
  18 static long cutoff = LONG_MAX;
  19
  20 /* How many generations are maximally preferred over _one_ merge traversal? */
  21 #define MERGE_TRAVERSAL_WEIGHT 65535
  22
  23 static void name_rev(struct commit *commit,
  24                 const char *tip_name, unsigned long taggerdate,
  25                 int generation, int distance,
  26                 int deref)
  27 {
  28         struct rev_name *name = (struct rev_name *)commit->util;
  29         struct commit_list *parents;
  30         int parent_number = 1;
  31
  32         parse_commit(commit);
  33
  34         if (commit->date < cutoff)
  35                 return;
  36
  37         if (deref) {
  38                 tip_name = xstrfmt("%s^0", tip_name);
  39
  40                 if (generation)
  41                         die("generation: %d, but deref?", generation);
  42         }
  43
  44         if (name == NULL) {
  45                 name = xmalloc(sizeof(rev_name));
  46                 commit->util = name;
  47                 goto copy_data;
  48         } else if (name->taggerdate > taggerdate ||
  49                         (name->taggerdate == taggerdate &&
  50                          name->distance > distance)) {
  51 copy_data:
  52                 name->tip_name = tip_name;
  53                 name->taggerdate = taggerdate;
  54                 name->generation = generation;
  55                 name->distance = distance;
  56         } else
  57                 return;
  58
  59         for (parents = commit->parents;
  60                         parents;
  61                         parents = parents->next, parent_number++) {
  62                 if (parent_number > 1) {
  63                         size_t len;
  64                         char *new_name;
  65
  66                         strip_suffix(tip_name, "^0", &len);
  67                         if (generation > 0)
  68                                 new_name = xstrfmt("%.*s~%d^%d", (int)len, tip_name,
  69                                                    generation, parent_number);
  70                         else
  71                                 new_name = xstrfmt("%.*s^%d", (int)len, tip_name,
  72                                                    parent_number);
  73
  74                         name_rev(parents->item, new_name, taggerdate, 0,
  75                                 distance + MERGE_TRAVERSAL_WEIGHT, 0);
  76                 } else {
  77                         name_rev(parents->item, tip_name, taggerdate,
  78                                 generation + 1, distance + 1, 0);
  79                 }
  80         }
  81 }
  82
  83 static int subpath_matches(const char *path, const char *filter)
  84 {
  85         const char *subpath = path;
  86
  87         while (subpath) {
  88                 if (!wildmatch(filter, subpath, 0, NULL))
  89                         return subpath - path;
  90                 subpath = strchr(subpath, '/');
  91                 if (subpath)
  92                         subpath++;
  93         }
  94         return -1;
  95 }
  96
  97 static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
  98 {
  99         if (shorten_unambiguous)
 100                 refname = shorten_unambiguous_ref(refname, 0);
 101         else if (starts_with(refname, "refs/heads/"))
 102                 refname = refname + 11;
 103         else if (starts_with(refname, "refs/"))
 104                 refname = refname + 5;
 105         return refname;
 106 }
 107
 108 struct name_ref_data {
 109         int tags_only;
 110         int name_only;
 111         const char *ref_filter;
 112 };
 113
 114 static struct tip_table {
 115         struct tip_table_entry {
 116                 unsigned char sha1[20];
 117                 const char *refname;
 118         } *table;
 119         int nr;
 120         int alloc;
 121         int sorted;
 122 } tip_table;
 123
 124 static void add_to_tip_table(const unsigned char *sha1, const char *refname,
 125                              int shorten_unambiguous)
 126 {
 127         refname = name_ref_abbrev(refname, shorten_unambiguous);
 128
 129         ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
 130         hashcpy(tip_table.table[tip_table.nr].sha1, sha1);
 131         tip_table.table[tip_table.nr].refname = xstrdup(refname);
 132         tip_table.nr++;
 133         tip_table.sorted = 0;
 134 }
 135
 136 static int tipcmp(const void *a_, const void *b_)
 137 {
 138         const struct tip_table_entry *a = a_, *b = b_;
 139         return hashcmp(a->sha1, b->sha1);
 140 }
 141
 142 static int name_ref(const char *path, const struct object_id *oid, int flags, void *cb_data)
 143 {
 144         struct object *o = parse_object(oid->hash);
 145         struct name_ref_data *data = cb_data;
 146         int can_abbreviate_output = data->tags_only && data->name_only;
 147         int deref = 0;
 148         unsigned long taggerdate = ULONG_MAX;
 149
 150         if (data->tags_only && !starts_with(path, "refs/tags/"))
 151                 return 0;
 152
 153         if (data->ref_filter) {
 154                 switch (subpath_matches(path, data->ref_filter)) {
 155                 case -1: /* did not match */
 156                         return 0;
 157                 case 0:  /* matched fully */
 158                         break;
 159                 default: /* matched subpath */
 160                         can_abbreviate_output = 1;
 161                         break;
 162                 }
 163         }
 164
 165         add_to_tip_table(oid->hash, path, can_abbreviate_output);
 166
 167         while (o && o->type == OBJ_TAG) {
 168                 struct tag *t = (struct tag *) o;
 169                 if (!t->tagged)
 170                         break; /* broken repository */
 171                 o = parse_object(t->tagged->oid.hash);
 172                 deref = 1;
 173                 taggerdate = t->date;
 174         }
 175         if (o && o->type == OBJ_COMMIT) {
 176                 struct commit *commit = (struct commit *)o;
 177
 178                 path = name_ref_abbrev(path, can_abbreviate_output);
 179                 name_rev(commit, xstrdup(path), taggerdate, 0, 0, deref);
 180         }
 181         return 0;
 182 }
 183
 184 static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
 185 {
 186         struct tip_table_entry *table = table_;
 187         return table[ix].sha1;
 188 }
 189
 190 static const char *get_exact_ref_match(const struct object *o)
 191 {
 192         int found;
 193
 194         if (!tip_table.table || !tip_table.nr)
 195                 return NULL;
 196
 197         if (!tip_table.sorted) {
 198                 qsort(tip_table.table, tip_table.nr, sizeof(*tip_table.table),
 199                       tipcmp);
 200                 tip_table.sorted = 1;
 201         }
 202
 203         found = sha1_pos(o->oid.hash, tip_table.table, tip_table.nr,
 204                          nth_tip_table_ent);
 205         if (0 <= found)
 206                 return tip_table.table[found].refname;
 207         return NULL;
 208 }
 209
 210 /* returns a static buffer */
 211 static const char *get_rev_name(const struct object *o)
 212 {
 213         static char buffer[1024];
 214         struct rev_name *n;
 215         struct commit *c;
 216
 217         if (o->type != OBJ_COMMIT)
 218                 return get_exact_ref_match(o);
 219         c = (struct commit *) o;
 220         n = c->util;
 221         if (!n)
 222                 return NULL;
 223
 224         if (!n->generation)
 225                 return n->tip_name;
 226         else {
 227                 int len = strlen(n->tip_name);
 228                 if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 229                         len -= 2;
 230                 snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
 231                                 n->generation);
 232
 233                 return buffer;
 234         }
 235 }
 236
 237 static void show_name(const struct object *obj,
 238                       const char *caller_name,
 239                       int always, int allow_undefined, int name_only)
 240 {
 241         const char *name;
 242         const struct object_id *oid = &obj->oid;
 243
 244         if (!name_only)
 245                 printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
 246         name = get_rev_name(obj);
 247         if (name)
 248                 printf("%s\n", name);
 249         else if (allow_undefined)
 250                 printf("undefined\n");
 251         else if (always)
 252                 printf("%s\n", find_unique_abbrev(oid->hash, DEFAULT_ABBREV));
 253         else
 254                 die("cannot describe '%s'", oid_to_hex(oid));
 255 }
 256
 257 static char const * const name_rev_usage[] = {
 258         N_("git name-rev [<options>] <commit>..."),
 259         N_("git name-rev [<options>] --all"),
 260         N_("git name-rev [<options>] --stdin"),
 261         NULL
 262 };
 263
 264 static void name_rev_line(char *p, struct name_ref_data *data)
 265 {
 266         int forty = 0;
 267         char *p_start;
 268         for (p_start = p; *p; p++) {
 269 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 270                 if (!ishex(*p))
 271                         forty = 0;
 272                 else if (++forty == 40 &&
 273                          !ishex(*(p+1))) {
 274                         unsigned char sha1[40];
 275                         const char *name = NULL;
 276                         char c = *(p+1);
 277                         int p_len = p - p_start + 1;
 278
 279                         forty = 0;
 280
 281                         *(p+1) = 0;
 282                         if (!get_sha1(p - 39, sha1)) {
 283                                 struct object *o =
 284                                         lookup_object(sha1);
 285                                 if (o)
 286                                         name = get_rev_name(o);
 287                         }
 288                         *(p+1) = c;
 289
 290                         if (!name)
 291                                 continue;
 292
 293                         if (data->name_only)
 294                                 printf("%.*s%s", p_len - 40, p_start, name);
 295                         else
 296                                 printf("%.*s (%s)", p_len, p_start, name);
 297                         p_start = p + 1;
 298                 }
 299         }
 300
 301         /* flush */
 302         if (p_start != p)
 303                 fwrite(p_start, p - p_start, 1, stdout);
 304 }
 305
 306 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 307 {
 308         struct object_array revs = OBJECT_ARRAY_INIT;
 309         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 310         struct name_ref_data data = { 0, 0, NULL };
 311         struct option opts[] = {
 312                 OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 313                 OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 314                 OPT_STRING(0, "refs", &data.ref_filter, N_("pattern"),
 315                                    N_("only use refs matching <pattern>")),
 316                 OPT_GROUP(""),
 317                 OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
 318                 OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
 319                 OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
 320                 OPT_BOOL(0, "always",     &always,
 321                            N_("show abbreviated commit object as fallback")),
 322                 {
 323                         /* A Hidden OPT_BOOL */
 324                         OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
 325                         N_("dereference tags in the input (internal use)"),
 326                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
 327                 },
 328                 OPT_END(),
 329         };
 330
 331         git_config(git_default_config, NULL);
 332         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 333         if (all + transform_stdin + !!argc > 1) {
 334                 error("Specify either a list, or --all, not both!");
 335                 usage_with_options(name_rev_usage, opts);
 336         }
 337         if (all || transform_stdin)
 338                 cutoff = 0;
 339
 340         for (; argc; argc--, argv++) {
 341                 unsigned char sha1[20];
 342                 struct object *object;
 343                 struct commit *commit;
 344
 345                 if (get_sha1(*argv, sha1)) {
 346                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 347                                         *argv);
 348                         continue;
 349                 }
 350
 351                 commit = NULL;
 352                 object = parse_object(sha1);
 353                 if (object) {
 354                         struct object *peeled = deref_tag(object, *argv, 0);
 355                         if (peeled && peeled->type == OBJ_COMMIT)
 356                                 commit = (struct commit *)peeled;
 357                 }
 358
 359                 if (!object) {
 360                         fprintf(stderr, "Could not get object for %s. Skipping.\n",
 361                                         *argv);
 362                         continue;
 363                 }
 364
 365                 if (commit) {
 366                         if (cutoff > commit->date)
 367                                 cutoff = commit->date;
 368                 }
 369
 370                 if (peel_tag) {
 371                         if (!commit) {
 372                                 fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 373                                         *argv);
 374                                 continue;
 375                         }
 376                         object = (struct object *)commit;
 377                 }
 378                 add_object_array(object, *argv, &revs);
 379         }
 380
 381         if (cutoff)
 382                 cutoff = cutoff - CUTOFF_DATE_SLOP;
 383         for_each_ref(name_ref, &data);
 384
 385         if (transform_stdin) {
 386                 char buffer[2048];
 387
 388                 while (!feof(stdin)) {
 389                         char *p = fgets(buffer, sizeof(buffer), stdin);
 390                         if (!p)
 391                                 break;
 392                         name_rev_line(p, &data);
 393                 }
 394         } else if (all) {
 395                 int i, max;
 396
 397                 max = get_max_object_index();
 398                 for (i = 0; i < max; i++) {
 399                         struct object *obj = get_indexed_object(i);
 400                         if (!obj || obj->type != OBJ_COMMIT)
 401                                 continue;
 402                         show_name(obj, NULL,
 403                                   always, allow_undefined, data.name_only);
 404                 }
 405         } else {
 406                 int i;
 407                 for (i = 0; i < revs.nr; i++)
 408                         show_name(revs.objects[i].item, revs.objects[i].name,
 409                                   always, allow_undefined, data.name_only);
 410         }
 411
 412         return 0;
 413 }