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 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 (!prefixcmp(refname, "refs/heads/"))
 104                 refname = refname + 11;
 105         else if (!prefixcmp(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 int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
 117 {
 118         struct object *o = parse_object(sha1);
 119         struct name_ref_data *data = cb_data;
 120         int can_abbreviate_output = data->tags_only && data->name_only;
 121         int deref = 0;
 122
 123         if (data->tags_only && prefixcmp(path, "refs/tags/"))
 124                 return 0;
 125
 126         if (data->ref_filter) {
 127                 switch (subpath_matches(path, data->ref_filter)) {
 128                 case -1: /* did not match */
 129                         return 0;
 130                 case 0:  /* matched fully */
 131                         break;
 132                 default: /* matched subpath */
 133                         can_abbreviate_output = 1;
 134                         break;
 135                 }
 136         }
 137
 138         while (o && o->type == OBJ_TAG) {
 139                 struct tag *t = (struct tag *) o;
 140                 if (!t->tagged)
 141                         break; /* broken repository */
 142                 o = parse_object(t->tagged->sha1);
 143                 deref = 1;
 144         }
 145         if (o && o->type == OBJ_COMMIT) {
 146                 struct commit *commit = (struct commit *)o;
 147
 148                 path = name_ref_abbrev(path, can_abbreviate_output);
 149                 name_rev(commit, xstrdup(path), 0, 0, deref);
 150         }
 151         return 0;
 152 }
 153
 154 /* returns a static buffer */
 155 static const char *get_rev_name(const struct object *o)
 156 {
 157         static char buffer[1024];
 158         struct rev_name *n;
 159         struct commit *c;
 160
 161         if (o->type != OBJ_COMMIT)
 162                 return NULL;
 163         c = (struct commit *) o;
 164         n = c->util;
 165         if (!n)
 166                 return NULL;
 167
 168         if (!n->generation)
 169                 return n->tip_name;
 170         else {
 171                 int len = strlen(n->tip_name);
 172                 if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 173                         len -= 2;
 174                 snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
 175                                 n->generation);
 176
 177                 return buffer;
 178         }
 179 }
 180
 181 static void show_name(const struct object *obj,
 182                       const char *caller_name,
 183                       int always, int allow_undefined, int name_only)
 184 {
 185         const char *name;
 186         const unsigned char *sha1 = obj->sha1;
 187
 188         if (!name_only)
 189                 printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
 190         name = get_rev_name(obj);
 191         if (name)
 192                 printf("%s\n", name);
 193         else if (allow_undefined)
 194                 printf("undefined\n");
 195         else if (always)
 196                 printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
 197         else
 198                 die("cannot describe '%s'", sha1_to_hex(sha1));
 199 }
 200
 201 static char const * const name_rev_usage[] = {
 202         N_("git name-rev [options] <commit>..."),
 203         N_("git name-rev [options] --all"),
 204         N_("git name-rev [options] --stdin"),
 205         NULL
 206 };
 207
 208 static void name_rev_line(char *p, struct name_ref_data *data)
 209 {
 210         int forty = 0;
 211         char *p_start;
 212         for (p_start = p; *p; p++) {
 213 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 214                 if (!ishex(*p))
 215                         forty = 0;
 216                 else if (++forty == 40 &&
 217                          !ishex(*(p+1))) {
 218                         unsigned char sha1[40];
 219                         const char *name = NULL;
 220                         char c = *(p+1);
 221                         int p_len = p - p_start + 1;
 222
 223                         forty = 0;
 224
 225                         *(p+1) = 0;
 226                         if (!get_sha1(p - 39, sha1)) {
 227                                 struct object *o =
 228                                         lookup_object(sha1);
 229                                 if (o)
 230                                         name = get_rev_name(o);
 231                         }
 232                         *(p+1) = c;
 233
 234                         if (!name)
 235                                 continue;
 236
 237                         if (data->name_only)
 238                                 printf("%.*s%s", p_len - 40, p_start, name);
 239                         else
 240                                 printf("%.*s (%s)", p_len, p_start, name);
 241                         p_start = p + 1;
 242                 }
 243         }
 244
 245         /* flush */
 246         if (p_start != p)
 247                 fwrite(p_start, p - p_start, 1, stdout);
 248 }
 249
 250 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 251 {
 252         struct object_array revs = OBJECT_ARRAY_INIT;
 253         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0;
 254         struct name_ref_data data = { 0, 0, NULL };
 255         struct option opts[] = {
 256                 OPT_BOOLEAN(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 257                 OPT_BOOLEAN(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 258                 OPT_STRING(0, "refs", &data.ref_filter, N_("pattern"),
 259                                    N_("only use refs matching <pattern>")),
 260                 OPT_GROUP(""),
 261                 OPT_BOOLEAN(0, "all", &all, N_("list all commits reachable from all refs")),
 262                 OPT_BOOLEAN(0, "stdin", &transform_stdin, N_("read from stdin")),
 263                 OPT_BOOLEAN(0, "undefined", &allow_undefined, N_("allow to print `undefined` names")),
 264                 OPT_BOOLEAN(0, "always",     &always,
 265                            N_("show abbreviated commit object as fallback")),
 266                 OPT_END(),
 267         };
 268
 269         git_config(git_default_config, NULL);
 270         argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 271         if (!!all + !!transform_stdin + !!argc > 1) {
 272                 error("Specify either a list, or --all, not both!");
 273                 usage_with_options(name_rev_usage, opts);
 274         }
 275         if (all || transform_stdin)
 276                 cutoff = 0;
 277
 278         for (; argc; argc--, argv++) {
 279                 unsigned char sha1[20];
 280                 struct object *o;
 281                 struct commit *commit;
 282
 283                 if (get_sha1(*argv, sha1)) {
 284                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 285                                         *argv);
 286                         continue;
 287                 }
 288
 289                 o = deref_tag(parse_object(sha1), *argv, 0);
 290                 if (!o || o->type != OBJ_COMMIT) {
 291                         fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 292                                         *argv);
 293                         continue;
 294                 }
 295
 296                 commit = (struct commit *)o;
 297                 if (cutoff > commit->date)
 298                         cutoff = commit->date;
 299                 add_object_array((struct object *)commit, *argv, &revs);
 300         }
 301
 302         if (cutoff)
 303                 cutoff = cutoff - CUTOFF_DATE_SLOP;
 304         for_each_ref(name_ref, &data);
 305
 306         if (transform_stdin) {
 307                 char buffer[2048];
 308
 309                 while (!feof(stdin)) {
 310                         char *p = fgets(buffer, sizeof(buffer), stdin);
 311                         if (!p)
 312                                 break;
 313                         name_rev_line(p, &data);
 314                 }
 315         } else if (all) {
 316                 int i, max;
 317
 318                 max = get_max_object_index();
 319                 for (i = 0; i < max; i++) {
 320                         struct object *obj = get_indexed_object(i);
 321                         if (!obj || obj->type != OBJ_COMMIT)
 322                                 continue;
 323                         show_name(obj, NULL,
 324                                   always, allow_undefined, data.name_only);
 325                 }
 326         } else {
 327                 int i;
 328                 for (i = 0; i < revs.nr; i++)
 329                         show_name(revs.objects[i].item, revs.objects[i].name,
 330                                   always, allow_undefined, data.name_only);
 331         }
 332
 333         return 0;
 334 }