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