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         if (!commit->object.parsed)
  31                 parse_commit(commit);
  32
  33         if (commit->date < cutoff)
  34                 return;
  35
  36         if (deref) {
  37                 char *new_name = xmalloc(strlen(tip_name)+3);
  38                 strcpy(new_name, tip_name);
  39                 strcat(new_name, "^0");
  40                 tip_name = new_name;
  41
  42                 if (generation)
  43                         die("generation: %d, but deref?", generation);
  44         }
  45
  46         if (name == NULL) {
  47                 name = xmalloc(sizeof(rev_name));
  48                 commit->util = name;
  49                 goto copy_data;
  50         } else if (name->distance > distance) {
  51 copy_data:
  52                 name->tip_name = tip_name;
  53                 name->generation = generation;
  54                 name->distance = distance;
  55         } else
  56                 return;
  57
  58         for (parents = commit->parents;
  59                         parents;
  60                         parents = parents->next, parent_number++) {
  61                 if (parent_number > 1) {
  62                         int len = strlen(tip_name);
  63                         char *new_name = xmalloc(len +
  64                                 1 + decimal_length(generation) +  /* ~<n> */
  65                                 1 + 2 +                           /* ^NN */
  66                                 1);
  67
  68                         if (len > 2 && !strcmp(tip_name + len - 2, "^0"))
  69                                 len -= 2;
  70                         if (generation > 0)
  71                                 sprintf(new_name, "%.*s~%d^%d", len, tip_name,
  72                                                 generation, parent_number);
  73                         else
  74                                 sprintf(new_name, "%.*s^%d", len, tip_name,
  75                                                 parent_number);
  76
  77                         name_rev(parents->item, new_name, 0,
  78                                 distance + MERGE_TRAVERSAL_WEIGHT, 0);
  79                 } else {
  80                         name_rev(parents->item, tip_name, generation + 1,
  81                                 distance + 1, 0);
  82                 }
  83         }
  84 }
  85
  86 static int subpath_matches(const char *path, const char *filter)
  87 {
  88         const char *subpath = path;
  89
  90         while (subpath) {
  91                 if (!fnmatch(filter, subpath, 0))
  92                         return subpath - path;
  93                 subpath = strchr(subpath, '/');
  94                 if (subpath)
  95                         subpath++;
  96         }
  97         return -1;
  98 }
  99
 100 static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
 101 {
 102         if (shorten_unambiguous)
 103                 refname = shorten_unambiguous_ref(refname, 0);
 104         else if (!prefixcmp(refname, "refs/heads/"))
 105                 refname = refname + 11;
 106         else if (!prefixcmp(refname, "refs/"))
 107                 refname = refname + 5;
 108         return refname;
 109 }
 110
 111 struct name_ref_data {
 112         int tags_only;
 113         int name_only;
 114         const char *ref_filter;
 115 };
 116
 117 static struct tip_table {
 118         struct tip_table_entry {
 119                 unsigned char sha1[20];
 120                 const char *refname;
 121         } *table;
 122         int nr;
 123         int alloc;
 124         int sorted;
 125 } tip_table;
 126
 127 static void add_to_tip_table(const unsigned char *sha1, const char *refname,
 128                              int shorten_unambiguous)
 129 {
 130         refname = name_ref_abbrev(refname, shorten_unambiguous);
 131
 132         ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
 133         hashcpy(tip_table.table[tip_table.nr].sha1, sha1);
 134         tip_table.table[tip_table.nr].refname = xstrdup(refname);
 135         tip_table.nr++;
 136         tip_table.sorted = 0;
 137 }
 138
 139 static int tipcmp(const void *a_, const void *b_)
 140 {
 141         const struct tip_table_entry *a = a_, *b = b_;
 142         return hashcmp(a->sha1, b->sha1);
 143 }
 144
 145 static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
 146 {
 147         struct object *o = parse_object(sha1);
 148         struct name_ref_data *data = cb_data;
 149         int can_abbreviate_output = data->tags_only && data->name_only;
 150         int deref = 0;
 151
 152         if (data->tags_only && prefixcmp(path, "refs/tags/"))
 153                 return 0;
 154
 155         if (data->ref_filter) {
 156                 switch (subpath_matches(path, data->ref_filter)) {
 157                 case -1: /* did not match */
 158                         return 0;
 159                 case 0:  /* matched fully */
 160                         break;
 161                 default: /* matched subpath */
 162                         can_abbreviate_output = 1;
 163                         break;
 164                 }
 165         }
 166
 167         add_to_tip_table(sha1, path, can_abbreviate_output);
 168
 169         while (o && o->type == OBJ_TAG) {
 170                 struct tag *t = (struct tag *) o;
 171                 if (!t->tagged)
 172                         break; /* broken repository */
 173                 o = parse_object(t->tagged->sha1);
 174                 deref = 1;
 175         }
 176         if (o && o->type == OBJ_COMMIT) {
 177                 struct commit *commit = (struct commit *)o;
 178
 179                 path = name_ref_abbrev(path, can_abbreviate_output);
 180                 name_rev(commit, xstrdup(path), 0, 0, deref);
 181         }
 182         return 0;
 183 }
 184
 185 static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
 186 {
 187         struct tip_table_entry *table = table_;
 188         return table[ix].sha1;
 189 }
 190
 191 static const char *get_exact_ref_match(const struct object *o)
 192 {
 193         int found;
 194
 195         if (!tip_table.table || !tip_table.nr)
 196                 return NULL;
 197
 198         if (!tip_table.sorted) {
 199                 qsort(tip_table.table, tip_table.nr, sizeof(*tip_table.table),
 200                       tipcmp);
 201                 tip_table.sorted = 1;
 202         }
 203
 204         found = sha1_pos(o->sha1, tip_table.table, tip_table.nr,
 205                          nth_tip_table_ent);
 206         if (0 <= found)
 207                 return tip_table.table[found].refname;
 208         return NULL;
 209 }
 210
 211 /* returns a static buffer */
 212 static const char *get_rev_name(const struct object *o)
 213 {
 214         static char buffer[1024];
 215         struct rev_name *n;
 216         struct commit *c;
 217
 218         if (o->type != OBJ_COMMIT)
 219                 return get_exact_ref_match(o);
 220         c = (struct commit *) o;
 221         n = c->util;
 222         if (!n)
 223                 return NULL;
 224
 225         if (!n->generation)
 226                 return n->tip_name;
 227         else {
 228                 int len = strlen(n->tip_name);
 229                 if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 230                         len -= 2;
 231                 snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
 232                                 n->generation);
 233
 234                 return buffer;
 235         }
 236 }
 237
 238 static void show_name(const struct object *obj,
 239                       const char *caller_name,
 240                       int always, int allow_undefined, int name_only)
 241 {
 242         const char *name;
 243         const unsigned char *sha1 = obj->sha1;
 244
 245         if (!name_only)
 246                 printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
 247         name = get_rev_name(obj);
 248         if (name)
 249                 printf("%s\n", name);
 250         else if (allow_undefined)
 251                 printf("undefined\n");
 252         else if (always)
 253                 printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
 254         else
 255                 die("cannot describe '%s'", sha1_to_hex(sha1));
 256 }
 257
 258 static char const * const name_rev_usage[] = {
 259         N_("git name-rev [options] <commit>..."),
 260         N_("git name-rev [options] --all"),
 261         N_("git name-rev [options] --stdin"),
 262         NULL
 263 };
 264
 265 static void name_rev_line(char *p, struct name_ref_data *data)
 266 {
 267         int forty = 0;
 268         char *p_start;
 269         for (p_start = p; *p; p++) {
 270 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 271                 if (!ishex(*p))
 272                         forty = 0;
 273                 else if (++forty == 40 &&
 274                          !ishex(*(p+1))) {
 275                         unsigned char sha1[40];
 276                         const char *name = NULL;
 277                         char c = *(p+1);
 278                         int p_len = p - p_start + 1;
 279
 280                         forty = 0;
 281
 282                         *(p+1) = 0;
 283                         if (!get_sha1(p - 39, sha1)) {
 284                                 struct object *o =
 285                                         lookup_object(sha1);
 286                                 if (o)
 287                                         name = get_rev_name(o);
 288                         }
 289                         *(p+1) = c;
 290
 291                         if (!name)
 292                                 continue;
 293
 294                         if (data->name_only)
 295                                 printf("%.*s%s", p_len - 40, p_start, name);
 296                         else
 297                                 printf("%.*s (%s)", p_len, p_start, name);
 298                         p_start = p + 1;
 299                 }
 300         }
 301
 302         /* flush */
 303         if (p_start != p)
 304                 fwrite(p_start, p - p_start, 1, stdout);
 305 }
 306
 307 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 308 {
 309         struct object_array revs = OBJECT_ARRAY_INIT;
 310         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 311         struct name_ref_data data = { 0, 0, NULL };
 312         struct option opts[] = {
 313                 OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 314                 OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 315                 OPT_STRING(0, "refs", &data.ref_filter, N_("pattern"),
 316                                    N_("only use refs matching <pattern>")),
 317                 OPT_GROUP(""),
 318                 OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
 319                 OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
 320                 OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
 321                 OPT_BOOL(0, "always",     &always,
 322                            N_("show abbreviated commit object as fallback")),
 323                 {
 324                         /* A Hidden OPT_BOOL */
 325                         OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
 326                         N_("dereference tags in the input (internal use)"),
 327                         PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
 328                 },
 329                 OPT_END(),
 330         };
 331
 332         git_config(git_default_config, NULL);
 333         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 334         if (all + transform_stdin + !!argc > 1) {
 335                 error("Specify either a list, or --all, not both!");
 336                 usage_with_options(name_rev_usage, opts);
 337         }
 338         if (all || transform_stdin)
 339                 cutoff = 0;
 340
 341         for (; argc; argc--, argv++) {
 342                 unsigned char sha1[20];
 343                 struct object *object;
 344                 struct commit *commit;
 345
 346                 if (get_sha1(*argv, sha1)) {
 347                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 348                                         *argv);
 349                         continue;
 350                 }
 351
 352                 commit = NULL;
 353                 object = parse_object(sha1);
 354                 if (object) {
 355                         struct object *peeled = deref_tag(object, *argv, 0);
 356                         if (peeled && peeled->type == OBJ_COMMIT)
 357                                 commit = (struct commit *)peeled;
 358                 }
 359
 360                 if (!object) {
 361                         fprintf(stderr, "Could not get object for %s. Skipping.\n",
 362                                         *argv);
 363                         continue;
 364                 }
 365
 366                 if (commit) {
 367                         if (cutoff > commit->date)
 368                                 cutoff = commit->date;
 369                 }
 370
 371                 if (peel_tag) {
 372                         if (!commit) {
 373                                 fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 374                                         *argv);
 375                                 continue;
 376                         }
 377                         object = (struct object *)commit;
 378                 }
 379                 add_object_array(object, *argv, &revs);
 380         }
 381
 382         if (cutoff)
 383                 cutoff = cutoff - CUTOFF_DATE_SLOP;
 384         for_each_ref(name_ref, &data);
 385
 386         if (transform_stdin) {
 387                 char buffer[2048];
 388
 389                 while (!feof(stdin)) {
 390                         char *p = fgets(buffer, sizeof(buffer), stdin);
 391                         if (!p)
 392                                 break;
 393                         name_rev_line(p, &data);
 394                 }
 395         } else if (all) {
 396                 int i, max;
 397
 398                 max = get_max_object_index();
 399                 for (i = 0; i < max; i++) {
 400                         struct object *obj = get_indexed_object(i);
 401                         if (!obj || obj->type != OBJ_COMMIT)
 402                                 continue;
 403                         show_name(obj, NULL,
 404                                   always, allow_undefined, data.name_only);
 405                 }
 406         } else {
 407                 int i;
 408                 for (i = 0; i < revs.nr; i++)
 409                         show_name(revs.objects[i].item, revs.objects[i].name,
 410                                   always, allow_undefined, data.name_only);
 411         }
 412
 413         return 0;
 414 }