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                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) {
  50copy_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
  85static 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
  99static 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
 110struct name_ref_data {
 111        int tags_only;
 112        int name_only;
 113        const char *ref_filter;
 114};
 115
 116static 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
 126static 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
 138static 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
 144static 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
 184static 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
 190static 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 */
 211static 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
 237static 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
 257static 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
 264static 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
 306int 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}