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 struct name_ref_data {
  86         int tags_only;
  87         int name_only;
  88         const char *ref_filter;
  89 };
  90
  91 static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
  92 {
  93         struct object *o = parse_object(sha1);
  94         struct name_ref_data *data = cb_data;
  95         int deref = 0;
  96
  97         if (data->tags_only && prefixcmp(path, "refs/tags/"))
  98                 return 0;
  99
 100         if (data->ref_filter && fnmatch(data->ref_filter, path, 0))
 101                 return 0;
 102
 103         while (o && o->type == OBJ_TAG) {
 104                 struct tag *t = (struct tag *) o;
 105                 if (!t->tagged)
 106                         break; /* broken repository */
 107                 o = parse_object(t->tagged->sha1);
 108                 deref = 1;
 109         }
 110         if (o && o->type == OBJ_COMMIT) {
 111                 struct commit *commit = (struct commit *)o;
 112
 113                 if (!prefixcmp(path, "refs/heads/"))
 114                         path = path + 11;
 115                 else if (data->tags_only
 116                     && data->name_only
 117                     && !prefixcmp(path, "refs/tags/"))
 118                         path = path + 10;
 119                 else if (!prefixcmp(path, "refs/"))
 120                         path = path + 5;
 121
 122                 name_rev(commit, xstrdup(path), 0, 0, deref);
 123         }
 124         return 0;
 125 }
 126
 127 /* returns a static buffer */
 128 static const char *get_rev_name(const struct object *o)
 129 {
 130         static char buffer[1024];
 131         struct rev_name *n;
 132         struct commit *c;
 133
 134         if (o->type != OBJ_COMMIT)
 135                 return NULL;
 136         c = (struct commit *) o;
 137         n = c->util;
 138         if (!n)
 139                 return NULL;
 140
 141         if (!n->generation)
 142                 return n->tip_name;
 143         else {
 144                 int len = strlen(n->tip_name);
 145                 if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 146                         len -= 2;
 147                 snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
 148                                 n->generation);
 149
 150                 return buffer;
 151         }
 152 }
 153
 154 static void show_name(const struct object *obj,
 155                       const char *caller_name,
 156                       int always, int allow_undefined, int name_only)
 157 {
 158         const char *name;
 159         const unsigned char *sha1 = obj->sha1;
 160
 161         if (!name_only)
 162                 printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
 163         name = get_rev_name(obj);
 164         if (name)
 165                 printf("%s\n", name);
 166         else if (allow_undefined)
 167                 printf("undefined\n");
 168         else if (always)
 169                 printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
 170         else
 171                 die("cannot describe '%s'", sha1_to_hex(sha1));
 172 }
 173
 174 static char const * const name_rev_usage[] = {
 175         "git-name-rev [options] ( --all | --stdin | <commit>... )",
 176         NULL
 177 };
 178
 179 static void name_rev_line(char *p, struct name_ref_data *data)
 180 {
 181         int forty = 0;
 182         char *p_start;
 183         for (p_start = p; *p; p++) {
 184 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 185                 if (!ishex(*p))
 186                         forty = 0;
 187                 else if (++forty == 40 &&
 188                          !ishex(*(p+1))) {
 189                         unsigned char sha1[40];
 190                         const char *name = NULL;
 191                         char c = *(p+1);
 192                         int p_len = p - p_start + 1;
 193
 194                         forty = 0;
 195
 196                         *(p+1) = 0;
 197                         if (!get_sha1(p - 39, sha1)) {
 198                                 struct object *o =
 199                                         lookup_object(sha1);
 200                                 if (o)
 201                                         name = get_rev_name(o);
 202                         }
 203                         *(p+1) = c;
 204
 205                         if (!name)
 206                                 continue;
 207
 208                         if (data->name_only)
 209                                 printf("%.*s%s", p_len - 40, p_start, name);
 210                         else
 211                                 printf("%.*s (%s)", p_len, p_start, name);
 212                         p_start = p + 1;
 213                 }
 214         }
 215
 216         /* flush */
 217         if (p_start != p)
 218                 fwrite(p_start, p - p_start, 1, stdout);
 219 }
 220
 221 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 222 {
 223         struct object_array revs = { 0, 0, NULL };
 224         int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0;
 225         struct name_ref_data data = { 0, 0, NULL };
 226         struct option opts[] = {
 227                 OPT_BOOLEAN(0, "name-only", &data.name_only, "print only names (no SHA-1)"),
 228                 OPT_BOOLEAN(0, "tags", &data.tags_only, "only use tags to name the commits"),
 229                 OPT_STRING(0, "refs", &data.ref_filter, "pattern",
 230                                    "only use refs matching <pattern>"),
 231                 OPT_GROUP(""),
 232                 OPT_BOOLEAN(0, "all", &all, "list all commits reachable from all refs"),
 233                 OPT_BOOLEAN(0, "stdin", &transform_stdin, "read from stdin"),
 234                 OPT_BOOLEAN(0, "undefined", &allow_undefined, "allow to print `undefined` names"),
 235                 OPT_BOOLEAN(0, "always",     &always,
 236                            "show abbreviated commit object as fallback"),
 237                 OPT_END(),
 238         };
 239
 240         git_config(git_default_config, NULL);
 241         argc = parse_options(argc, argv, opts, name_rev_usage, 0);
 242         if (!!all + !!transform_stdin + !!argc > 1) {
 243                 error("Specify either a list, or --all, not both!");
 244                 usage_with_options(name_rev_usage, opts);
 245         }
 246         if (all || transform_stdin)
 247                 cutoff = 0;
 248
 249         for (; argc; argc--, argv++) {
 250                 unsigned char sha1[20];
 251                 struct object *o;
 252                 struct commit *commit;
 253
 254                 if (get_sha1(*argv, sha1)) {
 255                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 256                                         *argv);
 257                         continue;
 258                 }
 259
 260                 o = deref_tag(parse_object(sha1), *argv, 0);
 261                 if (!o || o->type != OBJ_COMMIT) {
 262                         fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 263                                         *argv);
 264                         continue;
 265                 }
 266
 267                 commit = (struct commit *)o;
 268                 if (cutoff > commit->date)
 269                         cutoff = commit->date;
 270                 add_object_array((struct object *)commit, *argv, &revs);
 271         }
 272
 273         if (cutoff)
 274                 cutoff = cutoff - CUTOFF_DATE_SLOP;
 275         for_each_ref(name_ref, &data);
 276
 277         if (transform_stdin) {
 278                 char buffer[2048];
 279
 280                 while (!feof(stdin)) {
 281                         char *p = fgets(buffer, sizeof(buffer), stdin);
 282                         if (!p)
 283                                 break;
 284                         name_rev_line(p, &data);
 285                 }
 286         } else if (all) {
 287                 int i, max;
 288
 289                 max = get_max_object_index();
 290                 for (i = 0; i < max; i++) {
 291                         struct object *obj = get_indexed_object(i);
 292                         if (!obj)
 293                                 continue;
 294                         show_name(obj, NULL,
 295                                   always, allow_undefined, data.name_only);
 296                 }
 297         } else {
 298                 int i;
 299                 for (i = 0; i < revs.nr; i++)
 300                         show_name(revs.objects[i].item, revs.objects[i].name,
 301                                   always, allow_undefined, data.name_only);
 302         }
 303
 304         return 0;
 305 }