Andrew's git - gitweb.git/blob - 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
  11typedef struct rev_name {
  12        const char *tip_name;
  13        int generation;
  14        int distance;
  15} rev_name;
  16
  17static long cutoff = LONG_MAX;
  18
  19/* How many generations are maximally preferred over _one_ merge traversal? */
  20#define MERGE_TRAVERSAL_WEIGHT 65535
  21
  22static 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                tip_name = xstrfmt("%s^0", tip_name);
  37
  38                if (generation)
  39                        die("generation: %d, but deref?", generation);
  40        }
  41
  42        if (name == NULL) {
  43                name = xmalloc(sizeof(rev_name));
  44                commit->util = name;
  45                goto copy_data;
  46        } else if (name->distance > distance) {
  47copy_data:
  48                name->tip_name = tip_name;
  49                name->generation = generation;
  50                name->distance = distance;
  51        } else
  52                return;
  53
  54        for (parents = commit->parents;
  55                        parents;
  56                        parents = parents->next, parent_number++) {
  57                if (parent_number > 1) {
  58                        int len = strlen(tip_name);
  59                        char *new_name = xmalloc(len +
  60                                1 + decimal_length(generation) +  /* ~<n> */
  61                                1 + 2 +                           /* ^NN */
  62                                1);
  63
  64                        if (len > 2 && !strcmp(tip_name + len - 2, "^0"))
  65                                len -= 2;
  66                        if (generation > 0)
  67                                sprintf(new_name, "%.*s~%d^%d", len, tip_name,
  68                                                generation, parent_number);
  69                        else
  70                                sprintf(new_name, "%.*s^%d", len, tip_name,
  71                                                parent_number);
  72
  73                        name_rev(parents->item, new_name, 0,
  74                                distance + MERGE_TRAVERSAL_WEIGHT, 0);
  75                } else {
  76                        name_rev(parents->item, tip_name, generation + 1,
  77                                distance + 1, 0);
  78                }
  79        }
  80}
  81
  82static int subpath_matches(const char *path, const char *filter)
  83{
  84        const char *subpath = path;
  85
  86        while (subpath) {
  87                if (!wildmatch(filter, subpath, 0, NULL))
  88                        return subpath - path;
  89                subpath = strchr(subpath, '/');
  90                if (subpath)
  91                        subpath++;
  92        }
  93        return -1;
  94}
  95
  96static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
  97{
  98        if (shorten_unambiguous)
  99                refname = shorten_unambiguous_ref(refname, 0);
 100        else if (starts_with(refname, "refs/heads/"))
 101                refname = refname + 11;
 102        else if (starts_with(refname, "refs/"))
 103                refname = refname + 5;
 104        return refname;
 105}
 106
 107struct name_ref_data {
 108        int tags_only;
 109        int name_only;
 110        const char *ref_filter;
 111};
 112
 113static struct tip_table {
 114        struct tip_table_entry {
 115                unsigned char sha1[20];
 116                const char *refname;
 117        } *table;
 118        int nr;
 119        int alloc;
 120        int sorted;
 121} tip_table;
 122
 123static void add_to_tip_table(const unsigned char *sha1, const char *refname,
 124                             int shorten_unambiguous)
 125{
 126        refname = name_ref_abbrev(refname, shorten_unambiguous);
 127
 128        ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
 129        hashcpy(tip_table.table[tip_table.nr].sha1, sha1);
 130        tip_table.table[tip_table.nr].refname = xstrdup(refname);
 131        tip_table.nr++;
 132        tip_table.sorted = 0;
 133}
 134
 135static int tipcmp(const void *a_, const void *b_)
 136{
 137        const struct tip_table_entry *a = a_, *b = b_;
 138        return hashcmp(a->sha1, b->sha1);
 139}
 140
 141static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
 142{
 143        struct object *o = parse_object(sha1);
 144        struct name_ref_data *data = cb_data;
 145        int can_abbreviate_output = data->tags_only && data->name_only;
 146        int deref = 0;
 147
 148        if (data->tags_only && !starts_with(path, "refs/tags/"))
 149                return 0;
 150
 151        if (data->ref_filter) {
 152                switch (subpath_matches(path, data->ref_filter)) {
 153                case -1: /* did not match */
 154                        return 0;
 155                case 0:  /* matched fully */
 156                        break;
 157                default: /* matched subpath */
 158                        can_abbreviate_output = 1;
 159                        break;
 160                }
 161        }
 162
 163        add_to_tip_table(sha1, path, can_abbreviate_output);
 164
 165        while (o && o->type == OBJ_TAG) {
 166                struct tag *t = (struct tag *) o;
 167                if (!t->tagged)
 168                        break; /* broken repository */
 169                o = parse_object(t->tagged->sha1);
 170                deref = 1;
 171        }
 172        if (o && o->type == OBJ_COMMIT) {
 173                struct commit *commit = (struct commit *)o;
 174
 175                path = name_ref_abbrev(path, can_abbreviate_output);
 176                name_rev(commit, xstrdup(path), 0, 0, deref);
 177        }
 178        return 0;
 179}
 180
 181static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
 182{
 183        struct tip_table_entry *table = table_;
 184        return table[ix].sha1;
 185}
 186
 187static const char *get_exact_ref_match(const struct object *o)
 188{
 189        int found;
 190
 191        if (!tip_table.table || !tip_table.nr)
 192                return NULL;
 193
 194        if (!tip_table.sorted) {
 195                qsort(tip_table.table, tip_table.nr, sizeof(*tip_table.table),
 196                      tipcmp);
 197                tip_table.sorted = 1;
 198        }
 199
 200        found = sha1_pos(o->sha1, tip_table.table, tip_table.nr,
 201                         nth_tip_table_ent);
 202        if (0 <= found)
 203                return tip_table.table[found].refname;
 204        return NULL;
 205}
 206
 207/* returns a static buffer */
 208static const char *get_rev_name(const struct object *o)
 209{
 210        static char buffer[1024];
 211        struct rev_name *n;
 212        struct commit *c;
 213
 214        if (o->type != OBJ_COMMIT)
 215                return get_exact_ref_match(o);
 216        c = (struct commit *) o;
 217        n = c->util;
 218        if (!n)
 219                return NULL;
 220
 221        if (!n->generation)
 222                return n->tip_name;
 223        else {
 224                int len = strlen(n->tip_name);
 225                if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 226                        len -= 2;
 227                snprintf(buffer, sizeof(buffer), "%.*s~%d", len, n->tip_name,
 228                                n->generation);
 229
 230                return buffer;
 231        }
 232}
 233
 234static void show_name(const struct object *obj,
 235                      const char *caller_name,
 236                      int always, int allow_undefined, int name_only)
 237{
 238        const char *name;
 239        const unsigned char *sha1 = obj->sha1;
 240
 241        if (!name_only)
 242                printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
 243        name = get_rev_name(obj);
 244        if (name)
 245                printf("%s\n", name);
 246        else if (allow_undefined)
 247                printf("undefined\n");
 248        else if (always)
 249                printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
 250        else
 251                die("cannot describe '%s'", sha1_to_hex(sha1));
 252}
 253
 254static char const * const name_rev_usage[] = {
 255        N_("git name-rev [<options>] <commit>..."),
 256        N_("git name-rev [<options>] --all"),
 257        N_("git name-rev [<options>] --stdin"),
 258        NULL
 259};
 260
 261static void name_rev_line(char *p, struct name_ref_data *data)
 262{
 263        int forty = 0;
 264        char *p_start;
 265        for (p_start = p; *p; p++) {
 266#define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 267                if (!ishex(*p))
 268                        forty = 0;
 269                else if (++forty == 40 &&
 270                         !ishex(*(p+1))) {
 271                        unsigned char sha1[40];
 272                        const char *name = NULL;
 273                        char c = *(p+1);
 274                        int p_len = p - p_start + 1;
 275
 276                        forty = 0;
 277
 278                        *(p+1) = 0;
 279                        if (!get_sha1(p - 39, sha1)) {
 280                                struct object *o =
 281                                        lookup_object(sha1);
 282                                if (o)
 283                                        name = get_rev_name(o);
 284                        }
 285                        *(p+1) = c;
 286
 287                        if (!name)
 288                                continue;
 289
 290                        if (data->name_only)
 291                                printf("%.*s%s", p_len - 40, p_start, name);
 292                        else
 293                                printf("%.*s (%s)", p_len, p_start, name);
 294                        p_start = p + 1;
 295                }
 296        }
 297
 298        /* flush */
 299        if (p_start != p)
 300                fwrite(p_start, p - p_start, 1, stdout);
 301}
 302
 303int cmd_name_rev(int argc, const char **argv, const char *prefix)
 304{
 305        struct object_array revs = OBJECT_ARRAY_INIT;
 306        int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 307        struct name_ref_data data = { 0, 0, NULL };
 308        struct option opts[] = {
 309                OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 310                OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 311                OPT_STRING(0, "refs", &data.ref_filter, N_("pattern"),
 312                                   N_("only use refs matching <pattern>")),
 313                OPT_GROUP(""),
 314                OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
 315                OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
 316                OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
 317                OPT_BOOL(0, "always",     &always,
 318                           N_("show abbreviated commit object as fallback")),
 319                {
 320                        /* A Hidden OPT_BOOL */
 321                        OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
 322                        N_("dereference tags in the input (internal use)"),
 323                        PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
 324                },
 325                OPT_END(),
 326        };
 327
 328        git_config(git_default_config, NULL);
 329        argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 330        if (all + transform_stdin + !!argc > 1) {
 331                error("Specify either a list, or --all, not both!");
 332                usage_with_options(name_rev_usage, opts);
 333        }
 334        if (all || transform_stdin)
 335                cutoff = 0;
 336
 337        for (; argc; argc--, argv++) {
 338                unsigned char sha1[20];
 339                struct object *object;
 340                struct commit *commit;
 341
 342                if (get_sha1(*argv, sha1)) {
 343                        fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 344                                        *argv);
 345                        continue;
 346                }
 347
 348                commit = NULL;
 349                object = parse_object(sha1);
 350                if (object) {
 351                        struct object *peeled = deref_tag(object, *argv, 0);
 352                        if (peeled && peeled->type == OBJ_COMMIT)
 353                                commit = (struct commit *)peeled;
 354                }
 355
 356                if (!object) {
 357                        fprintf(stderr, "Could not get object for %s. Skipping.\n",
 358                                        *argv);
 359                        continue;
 360                }
 361
 362                if (commit) {
 363                        if (cutoff > commit->date)
 364                                cutoff = commit->date;
 365                }
 366
 367                if (peel_tag) {
 368                        if (!commit) {
 369                                fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 370                                        *argv);
 371                                continue;
 372                        }
 373                        object = (struct object *)commit;
 374                }
 375                add_object_array(object, *argv, &revs);
 376        }
 377
 378        if (cutoff)
 379                cutoff = cutoff - CUTOFF_DATE_SLOP;
 380        for_each_ref(name_ref, &data);
 381
 382        if (transform_stdin) {
 383                char buffer[2048];
 384
 385                while (!feof(stdin)) {
 386                        char *p = fgets(buffer, sizeof(buffer), stdin);
 387                        if (!p)
 388                                break;
 389                        name_rev_line(p, &data);
 390                }
 391        } else if (all) {
 392                int i, max;
 393
 394                max = get_max_object_index();
 395                for (i = 0; i < max; i++) {
 396                        struct object *obj = get_indexed_object(i);
 397                        if (!obj || obj->type != OBJ_COMMIT)
 398                                continue;
 399                        show_name(obj, NULL,
 400                                  always, allow_undefined, data.name_only);
 401                }
 402        } else {
 403                int i;
 404                for (i = 0; i < revs.nr; i++)
 405                        show_name(revs.objects[i].item, revs.objects[i].name,
 406                                  always, allow_undefined, data.name_only);
 407        }
 408
 409        return 0;
 410}