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
   8 #define CUTOFF_DATE_SLOP 86400 /* one day */
   9
  10 typedef struct rev_name {
  11         const char *tip_name;
  12         int generation;
  13         int distance;
  14 } rev_name;
  15
  16 static long cutoff = LONG_MAX;
  17
  18 /* How many generations are maximally preferred over _one_ merge traversal? */
  19 #define MERGE_TRAVERSAL_WEIGHT 65535
  20
  21 static void name_rev(struct commit *commit,
  22                 const char *tip_name, int generation, int distance,
  23                 int deref)
  24 {
  25         struct rev_name *name = (struct rev_name *)commit->util;
  26         struct commit_list *parents;
  27         int parent_number = 1;
  28
  29         if (!commit->object.parsed)
  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 (!fnmatch(filter, subpath, 0))
  91                         return subpath - path;
  92                 subpath = strchr(subpath, '/');
  93                 if (subpath)
  94                         subpath++;
  95         }
  96         return -1;
  97 }
  98
  99 struct name_ref_data {
 100         int tags_only;
 101         int name_only;
 102         const char *ref_filter;
 103 };
 104
 105 static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
 106 {
 107         struct object *o = parse_object(sha1);
 108         struct name_ref_data *data = cb_data;
 109         int can_abbreviate_output = data->tags_only && data->name_only;
 110         int deref = 0;
 111
 112         if (data->tags_only && prefixcmp(path, "refs/tags/"))
 113                 return 0;
 114
 115         if (data->ref_filter) {
 116                 switch (subpath_matches(path, data->ref_filter)) {
 117                 case -1: /* did not match */
 118                         return 0;
 119                 case 0:  /* matched fully */
 120                         break;
 121                 default: /* matched subpath */
 122                         can_abbreviate_output = 1;
 123                         break;
 124                 }
 125         }
 126
 127         while (o && o->type == OBJ_TAG) {
 128                 struct tag *t = (struct tag *) o;
 129                 if (!t->tagged)
 130                         break; /* broken repository */
 131                 o = parse_object(t->tagged->sha1);
 132                 deref = 1;
 133         }
 134         if (o && o->type == OBJ_COMMIT) {
 135                 struct commit *commit = (struct commit *)o;
 136
 137                 if (can_abbreviate_output)
 138                         path = shorten_unambiguous_ref(path, 0);
 139                 else if (!prefixcmp(path, "refs/heads/"))
 140                         path = path + 11;
 141                 else if (!prefixcmp(path, "refs/"))
 142                         path = path + 5;
 143
 144                 name_rev(commit, xstrdup(path), 0, 0, deref);
 145         }
 146         return 0;
 147 }
 148
 149 /* returns a static buffer */
 150 static const char *get_rev_name(const struct object *o)
 151 {
 152         static char buffer[1024];
 153         struct rev_name *n;
 154         struct commit *c;
 155
 156         if (o->type != OBJ_COMMIT)
 157                 return NULL;
 158         c = (struct commit *) o;
 159         n = c->util;
 160         if (!n)
 161                 return NULL;
 162
 163         if (!n->generation)
 164                 return n->tip_name;
 165         else {
 166                 int len = strlen(n->tip_name);
 167                 if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 168                         len -= 2;
 169                 snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
 170                                 n->generation);
 171
 172                 return buffer;
 173         }
 174 }
 175
 176 static void show_name(const struct object *obj,
 177                       const char *caller_name,
 178                       int always, int allow_undefined, int name_only)
 179 {
 180         const char *name;
 181         const unsigned char *sha1 = obj->sha1;
 182
 183         if (!name_only)
 184                 printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
 185         name = get_rev_name(obj);
 186         if (name)
 187                 printf("%s\n", name);
 188         else if (allow_undefined)
 189                 printf("undefined\n");
 190         else if (always)
 191                 printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
 192         else
 193                 die("cannot describe '%s'", sha1_to_hex(sha1));
 194 }
 195
 196 static char const * const name_rev_usage[] = {
 197         N_("git name-rev [options] <commit>..."),
 198         N_("git name-rev [options] --all"),
 199         N_("git name-rev [options] --stdin"),
 200         NULL
 201 };
 202
 203 static void name_rev_line(char *p, struct name_ref_data *data)
 204 {
 205         int forty = 0;
 206         char *p_start;
 207         for (p_start = p; *p; p++) {
 208 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 209                 if (!ishex(*p))
 210                         forty = 0;
 211                 else if (++forty == 40 &&
 212                          !ishex(*(p+1))) {
 213                         unsigned char sha1[40];
 214                         const char *name = NULL;
 215                         char c = *(p+1);
 216                         int p_len = p - p_start + 1;
 217
 218                         forty = 0;
 219
 220                         *(p+1) = 0;
 221                         if (!get_sha1(p - 39, sha1)) {
 222                                 struct object *o =
 223                                         lookup_object(sha1);
 224                                 if (o)
 225                                         name = get_rev_name(o);
 226                         }
 227                         *(p+1) = c;
 228
 229                         if (!name)
 230                                 continue;
 231
 232                         if (data->name_only)
 233                                 printf("%.*s%s", p_len - 40, p_start, name);
 234                         else
 235                                 printf("%.*s (%s)", p_len, p_start, name);
 236                         p_start = p + 1;
 237                 }
 238         }
 239
 240         /* flush */
 241         if (p_start != p)
 242                 fwrite(p_start, p - p_start, 1, stdout);
 243 }
 244
 245 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 246 {
 247         struct object_array revs = OBJECT_ARRAY_INIT;
 248         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0;
 249         struct name_ref_data data = { 0, 0, NULL };
 250         struct option opts[] = {
 251                 OPT_BOOLEAN(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 252                 OPT_BOOLEAN(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 253                 OPT_STRING(0, "refs", &data.ref_filter, N_("pattern"),
 254                                    N_("only use refs matching <pattern>")),
 255                 OPT_GROUP(""),
 256                 OPT_BOOLEAN(0, "all", &all, N_("list all commits reachable from all refs")),
 257                 OPT_BOOLEAN(0, "stdin", &transform_stdin, N_("read from stdin")),
 258                 OPT_BOOLEAN(0, "undefined", &allow_undefined, N_("allow to print `undefined` names")),
 259                 OPT_BOOLEAN(0, "always",     &always,
 260                            N_("show abbreviated commit object as fallback")),
 261                 OPT_END(),
 262         };
 263
 264         git_config(git_default_config, NULL);
 265         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 266         if (!!all + !!transform_stdin + !!argc > 1) {
 267                 error("Specify either a list, or --all, not both!");
 268                 usage_with_options(name_rev_usage, opts);
 269         }
 270         if (all || transform_stdin)
 271                 cutoff = 0;
 272
 273         for (; argc; argc--, argv++) {
 274                 unsigned char sha1[20];
 275                 struct object *o;
 276                 struct commit *commit;
 277
 278                 if (get_sha1(*argv, sha1)) {
 279                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 280                                         *argv);
 281                         continue;
 282                 }
 283
 284                 o = deref_tag(parse_object(sha1), *argv, 0);
 285                 if (!o || o->type != OBJ_COMMIT) {
 286                         fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 287                                         *argv);
 288                         continue;
 289                 }
 290
 291                 commit = (struct commit *)o;
 292                 if (cutoff > commit->date)
 293                         cutoff = commit->date;
 294                 add_object_array((struct object *)commit, *argv, &revs);
 295         }
 296
 297         if (cutoff)
 298                 cutoff = cutoff - CUTOFF_DATE_SLOP;
 299         for_each_ref(name_ref, &data);
 300
 301         if (transform_stdin) {
 302                 char buffer[2048];
 303
 304                 while (!feof(stdin)) {
 305                         char *p = fgets(buffer, sizeof(buffer), stdin);
 306                         if (!p)
 307                                 break;
 308                         name_rev_line(p, &data);
 309                 }
 310         } else if (all) {
 311                 int i, max;
 312
 313                 max = get_max_object_index();
 314                 for (i = 0; i < max; i++) {
 315                         struct object *obj = get_indexed_object(i);
 316                         if (!obj || obj->type != OBJ_COMMIT)
 317                                 continue;
 318                         show_name(obj, NULL,
 319                                   always, allow_undefined, data.name_only);
 320                 }
 321         } else {
 322                 int i;
 323                 for (i = 0; i < revs.nr; i++)
 324                         show_name(revs.objects[i].item, revs.objects[i].name,
 325                                   always, allow_undefined, data.name_only);
 326         }
 327
 328         return 0;
 329 }