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                 char *new_name = xmalloc(strlen(tip_name)+3);
  37                 strcpy(new_name, tip_name);
  38                 strcat(new_name, "^0");
  39                 tip_name = new_name;
  40
  41                 if (generation)
  42                         die("generation: %d, but deref?", generation);
  43         }
  44
  45         if (name == NULL) {
  46                 name = xmalloc(sizeof(rev_name));
  47                 commit->util = name;
  48                 goto copy_data;
  49         } else if (name->distance > distance) {
  50 copy_data:
  51                 name->tip_name = tip_name;
  52                 name->generation = generation;
  53                 name->distance = distance;
  54         } else
  55                 return;
  56
  57         for (parents = commit->parents;
  58                         parents;
  59                         parents = parents->next, parent_number++) {
  60                 if (parent_number > 1) {
  61                         int len = strlen(tip_name);
  62                         char *new_name = xmalloc(len +
  63                                 1 + decimal_length(generation) +  /* ~<n> */
  64                                 1 + 2 +                           /* ^NN */
  65                                 1);
  66
  67                         if (len > 2 && !strcmp(tip_name + len - 2, "^0"))
  68                                 len -= 2;
  69                         if (generation > 0)
  70                                 sprintf(new_name, "%.*s~%d^%d", len, tip_name,
  71                                                 generation, parent_number);
  72                         else
  73                                 sprintf(new_name, "%.*s^%d", len, tip_name,
  74                                                 parent_number);
  75
  76                         name_rev(parents->item, new_name, 0,
  77                                 distance + MERGE_TRAVERSAL_WEIGHT, 0);
  78                 } else {
  79                         name_rev(parents->item, tip_name, generation + 1,
  80                                 distance + 1, 0);
  81                 }
  82         }
  83 }
  84
  85 static int subpath_matches(const char *path, const char *filter)
  86 {
  87         const char *subpath = path;
  88
  89         while (subpath) {
  90                 if (!wildmatch(filter, subpath, 0, NULL))
  91                         return subpath - path;
  92                 subpath = strchr(subpath, '/');
  93                 if (subpath)
  94                         subpath++;
  95         }
  96         return -1;
  97 }
  98
  99 static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
 100 {
 101         if (shorten_unambiguous)
 102                 refname = shorten_unambiguous_ref(refname, 0);
 103         else if (starts_with(refname, "refs/heads/"))
 104                 refname = refname + 11;
 105         else if (starts_with(refname, "refs/"))
 106                 refname = refname + 5;
 107         return refname;
 108 }
 109
 110 struct name_ref_data {
 111         int tags_only;
 112         int name_only;
 113         const char *ref_filter;
 114 };
 115
 116 static struct tip_table {
 117         struct tip_table_entry {
 118                 unsigned char sha1[20];
 119                 const char *refname;
 120         } *table;
 121         int nr;
 122         int alloc;
 123         int sorted;
 124 } tip_table;
 125
 126 static void add_to_tip_table(const unsigned char *sha1, const char *refname,
 127                              int shorten_unambiguous)
 128 {
 129         refname = name_ref_abbrev(refname, shorten_unambiguous);
 130
 131         ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
 132         hashcpy(tip_table.table[tip_table.nr].sha1, sha1);
 133         tip_table.table[tip_table.nr].refname = xstrdup(refname);
 134         tip_table.nr++;
 135         tip_table.sorted = 0;
 136 }
 137
 138 static int tipcmp(const void *a_, const void *b_)
 139 {
 140         const struct tip_table_entry *a = a_, *b = b_;
 141         return hashcmp(a->sha1, b->sha1);
 142 }
 143
 144 static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
 145 {
 146         struct object *o = parse_object(sha1);
 147         struct name_ref_data *data = cb_data;
 148         int can_abbreviate_output = data->tags_only && data->name_only;
 149         int deref = 0;
 150
 151         if (data->tags_only && !starts_with(path, "refs/tags/"))
 152                 return 0;
 153
 154         if (data->ref_filter) {
 155                 switch (subpath_matches(path, data->ref_filter)) {
 156                 case -1: /* did not match */
 157                         return 0;
 158                 case 0:  /* matched fully */
 159                         break;
 160                 default: /* matched subpath */
 161                         can_abbreviate_output = 1;
 162                         break;
 163                 }
 164         }
 165
 166         add_to_tip_table(sha1, path, can_abbreviate_output);
 167
 168         while (o && o->type == OBJ_TAG) {
 169                 struct tag *t = (struct tag *) o;
 170                 if (!t->tagged)
 171                         break; /* broken repository */
 172                 o = parse_object(t->tagged->sha1);
 173                 deref = 1;
 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), 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->sha1, 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 unsigned char *sha1 = obj->sha1;
 243
 244         if (!name_only)
 245                 printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
 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(sha1, DEFAULT_ABBREV));
 253         else
 254                 die("cannot describe '%s'", sha1_to_hex(sha1));
 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 }