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                         int len = strlen(tip_name);
  59                         char *new_name = xmalloc(len +
  60                                 1 + decimal_length(generation) +  /* ~<n> */
  61                                 1 + 2 +                           /* ^NN */
  62                                 1);
  63
  64                         if (len > 2 && !strcmp(tip_name + len - 2, "^0"))
  65                                 len -= 2;
  66                         if (generation > 0)
  67                                 sprintf(new_name, "%.*s~%d^%d", len, tip_name,
  68                                                 generation, parent_number);
  69                         else
  70                                 sprintf(new_name, "%.*s^%d", len, tip_name,
  71                                                 parent_number);
  72
  73                         name_rev(parents->item, new_name, 0,
  74                                 distance + MERGE_TRAVERSAL_WEIGHT, 0);
  75                 } else {
  76                         name_rev(parents->item, tip_name, generation + 1,
  77                                 distance + 1, 0);
  78                 }
  79         }
  80 }
  81
  82 static int subpath_matches(const char *path, const char *filter)
  83 {
  84         const char *subpath = path;
  85
  86         while (subpath) {
  87                 if (!wildmatch(filter, subpath, 0, NULL))
  88                         return subpath - path;
  89                 subpath = strchr(subpath, '/');
  90                 if (subpath)
  91                         subpath++;
  92         }
  93         return -1;
  94 }
  95
  96 static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
  97 {
  98         if (shorten_unambiguous)
  99                 refname = shorten_unambiguous_ref(refname, 0);
 100         else if (starts_with(refname, "refs/heads/"))
 101                 refname = refname + 11;
 102         else if (starts_with(refname, "refs/"))
 103                 refname = refname + 5;
 104         return refname;
 105 }
 106
 107 struct name_ref_data {
 108         int tags_only;
 109         int name_only;
 110         const char *ref_filter;
 111 };
 112
 113 static struct tip_table {
 114         struct tip_table_entry {
 115                 unsigned char sha1[20];
 116                 const char *refname;
 117         } *table;
 118         int nr;
 119         int alloc;
 120         int sorted;
 121 } tip_table;
 122
 123 static void add_to_tip_table(const unsigned char *sha1, const char *refname,
 124                              int shorten_unambiguous)
 125 {
 126         refname = name_ref_abbrev(refname, shorten_unambiguous);
 127
 128         ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
 129         hashcpy(tip_table.table[tip_table.nr].sha1, sha1);
 130         tip_table.table[tip_table.nr].refname = xstrdup(refname);
 131         tip_table.nr++;
 132         tip_table.sorted = 0;
 133 }
 134
 135 static int tipcmp(const void *a_, const void *b_)
 136 {
 137         const struct tip_table_entry *a = a_, *b = b_;
 138         return hashcmp(a->sha1, b->sha1);
 139 }
 140
 141 static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
 142 {
 143         struct object *o = parse_object(sha1);
 144         struct name_ref_data *data = cb_data;
 145         int can_abbreviate_output = data->tags_only && data->name_only;
 146         int deref = 0;
 147
 148         if (data->tags_only && !starts_with(path, "refs/tags/"))
 149                 return 0;
 150
 151         if (data->ref_filter) {
 152                 switch (subpath_matches(path, data->ref_filter)) {
 153                 case -1: /* did not match */
 154                         return 0;
 155                 case 0:  /* matched fully */
 156                         break;
 157                 default: /* matched subpath */
 158                         can_abbreviate_output = 1;
 159                         break;
 160                 }
 161         }
 162
 163         add_to_tip_table(sha1, path, can_abbreviate_output);
 164
 165         while (o && o->type == OBJ_TAG) {
 166                 struct tag *t = (struct tag *) o;
 167                 if (!t->tagged)
 168                         break; /* broken repository */
 169                 o = parse_object(t->tagged->sha1);
 170                 deref = 1;
 171         }
 172         if (o && o->type == OBJ_COMMIT) {
 173                 struct commit *commit = (struct commit *)o;
 174
 175                 path = name_ref_abbrev(path, can_abbreviate_output);
 176                 name_rev(commit, xstrdup(path), 0, 0, deref);
 177         }
 178         return 0;
 179 }
 180
 181 static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
 182 {
 183         struct tip_table_entry *table = table_;
 184         return table[ix].sha1;
 185 }
 186
 187 static const char *get_exact_ref_match(const struct object *o)
 188 {
 189         int found;
 190
 191         if (!tip_table.table || !tip_table.nr)
 192                 return NULL;
 193
 194         if (!tip_table.sorted) {
 195                 qsort(tip_table.table, tip_table.nr, sizeof(*tip_table.table),
 196                       tipcmp);
 197                 tip_table.sorted = 1;
 198         }
 199
 200         found = sha1_pos(o->sha1, tip_table.table, tip_table.nr,
 201                          nth_tip_table_ent);
 202         if (0 <= found)
 203                 return tip_table.table[found].refname;
 204         return NULL;
 205 }
 206
 207 /* returns a static buffer */
 208 static const char *get_rev_name(const struct object *o)
 209 {
 210         static char buffer[1024];
 211         struct rev_name *n;
 212         struct commit *c;
 213
 214         if (o->type != OBJ_COMMIT)
 215                 return get_exact_ref_match(o);
 216         c = (struct commit *) o;
 217         n = c->util;
 218         if (!n)
 219                 return NULL;
 220
 221         if (!n->generation)
 222                 return n->tip_name;
 223         else {
 224                 int len = strlen(n->tip_name);
 225                 if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 226                         len -= 2;
 227                 snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
 228                                 n->generation);
 229
 230                 return buffer;
 231         }
 232 }
 233
 234 static void show_name(const struct object *obj,
 235                       const char *caller_name,
 236                       int always, int allow_undefined, int name_only)
 237 {
 238         const char *name;
 239         const unsigned char *sha1 = obj->sha1;
 240
 241         if (!name_only)
 242                 printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
 243         name = get_rev_name(obj);
 244         if (name)
 245                 printf("%s\n", name);
 246         else if (allow_undefined)
 247                 printf("undefined\n");
 248         else if (always)
 249                 printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
 250         else
 251                 die("cannot describe '%s'", sha1_to_hex(sha1));
 252 }
 253
 254 static char const * const name_rev_usage[] = {
 255         N_("git name-rev [<options>] <commit>..."),
 256         N_("git name-rev [<options>] --all"),
 257         N_("git name-rev [<options>] --stdin"),
 258         NULL
 259 };
 260
 261 static void name_rev_line(char *p, struct name_ref_data *data)
 262 {
 263         int forty = 0;
 264         char *p_start;
 265         for (p_start = p; *p; p++) {
 266 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 267                 if (!ishex(*p))
 268                         forty = 0;
 269                 else if (++forty == 40 &&
 270                          !ishex(*(p+1))) {
 271                         unsigned char sha1[40];
 272                         const char *name = NULL;
 273                         char c = *(p+1);
 274                         int p_len = p - p_start + 1;
 275
 276                         forty = 0;
 277
 278                         *(p+1) = 0;
 279                         if (!get_sha1(p - 39, sha1)) {
 280                                 struct object *o =
 281                                         lookup_object(sha1);
 282                                 if (o)
 283                                         name = get_rev_name(o);
 284                         }
 285                         *(p+1) = c;
 286
 287                         if (!name)
 288                                 continue;
 289
 290                         if (data->name_only)
 291                                 printf("%.*s%s", p_len - 40, p_start, name);
 292                         else
 293                                 printf("%.*s (%s)", p_len, p_start, name);
 294                         p_start = p + 1;
 295                 }
 296         }
 297
 298         /* flush */
 299         if (p_start != p)
 300                 fwrite(p_start, p - p_start, 1, stdout);
 301 }
 302
 303 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 304 {
 305         struct object_array revs = OBJECT_ARRAY_INIT;
 306         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 307         struct name_ref_data data = { 0, 0, NULL };
 308         struct option opts[] = {
 309                 OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 310                 OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 311                 OPT_STRING(0, "refs", &data.ref_filter, N_("pattern"),
 312                                    N_("only use refs matching <pattern>")),
 313                 OPT_GROUP(""),
 314                 OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
 315                 OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
 316                 OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
 317                 OPT_BOOL(0, "always",     &always,
 318                            N_("show abbreviated commit object as fallback")),
 319                 {
 320                         /* A Hidden OPT_BOOL */
 321                         OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
 322                         N_("dereference tags in the input (internal use)"),
 323                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
 324                 },
 325                 OPT_END(),
 326         };
 327
 328         git_config(git_default_config, NULL);
 329         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 330         if (all + transform_stdin + !!argc > 1) {
 331                 error("Specify either a list, or --all, not both!");
 332                 usage_with_options(name_rev_usage, opts);
 333         }
 334         if (all || transform_stdin)
 335                 cutoff = 0;
 336
 337         for (; argc; argc--, argv++) {
 338                 unsigned char sha1[20];
 339                 struct object *object;
 340                 struct commit *commit;
 341
 342                 if (get_sha1(*argv, sha1)) {
 343                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 344                                         *argv);
 345                         continue;
 346                 }
 347
 348                 commit = NULL;
 349                 object = parse_object(sha1);
 350                 if (object) {
 351                         struct object *peeled = deref_tag(object, *argv, 0);
 352                         if (peeled && peeled->type == OBJ_COMMIT)
 353                                 commit = (struct commit *)peeled;
 354                 }
 355
 356                 if (!object) {
 357                         fprintf(stderr, "Could not get object for %s. Skipping.\n",
 358                                         *argv);
 359                         continue;
 360                 }
 361
 362                 if (commit) {
 363                         if (cutoff > commit->date)
 364                                 cutoff = commit->date;
 365                 }
 366
 367                 if (peel_tag) {
 368                         if (!commit) {
 369                                 fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 370                                         *argv);
 371                                 continue;
 372                         }
 373                         object = (struct object *)commit;
 374                 }
 375                 add_object_array(object, *argv, &revs);
 376         }
 377
 378         if (cutoff)
 379                 cutoff = cutoff - CUTOFF_DATE_SLOP;
 380         for_each_ref(name_ref, &data);
 381
 382         if (transform_stdin) {
 383                 char buffer[2048];
 384
 385                 while (!feof(stdin)) {
 386                         char *p = fgets(buffer, sizeof(buffer), stdin);
 387                         if (!p)
 388                                 break;
 389                         name_rev_line(p, &data);
 390                 }
 391         } else if (all) {
 392                 int i, max;
 393
 394                 max = get_max_object_index();
 395                 for (i = 0; i < max; i++) {
 396                         struct object *obj = get_indexed_object(i);
 397                         if (!obj || obj->type != OBJ_COMMIT)
 398                                 continue;
 399                         show_name(obj, NULL,
 400                                   always, allow_undefined, data.name_only);
 401                 }
 402         } else {
 403                 int i;
 404                 for (i = 0; i < revs.nr; i++)
 405                         show_name(revs.objects[i].item, revs.objects[i].name,
 406                                   always, allow_undefined, data.name_only);
 407         }
 408
 409         return 0;
 410 }