builtin-name-rev.con commit checkout: notice when the switched branch is behind or forked (79a1e6b)
   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
  10typedef struct rev_name {
  11        const char *tip_name;
  12        int generation;
  13        int distance;
  14} rev_name;
  15
  16static long cutoff = LONG_MAX;
  17
  18/* How many generations are maximally preferred over _one_ merge traversal? */
  19#define MERGE_TRAVERSAL_WEIGHT 65535
  20
  21static 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) {
  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
  85struct name_ref_data {
  86        int tags_only;
  87        int name_only;
  88        const char *ref_filter;
  89};
  90
  91static 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 */
 128static const char* get_rev_name(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 "undefined";
 136        c = (struct commit *) o;
 137        n = c->util;
 138        if (!n)
 139                return "undefined";
 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
 154static char const * const name_rev_usage[] = {
 155        "git-name-rev [options] ( --all | --stdin | <commit>... )",
 156        NULL
 157};
 158
 159int cmd_name_rev(int argc, const char **argv, const char *prefix)
 160{
 161        struct object_array revs = { 0, 0, NULL };
 162        int all = 0, transform_stdin = 0;
 163        struct name_ref_data data = { 0, 0, NULL };
 164        struct option opts[] = {
 165                OPT_BOOLEAN(0, "name-only", &data.name_only, "print only names (no SHA-1)"),
 166                OPT_BOOLEAN(0, "tags", &data.tags_only, "only use tags to name the commits"),
 167                OPT_STRING(0, "refs", &data.ref_filter, "pattern",
 168                                   "only use refs matching <pattern>"),
 169                OPT_GROUP(""),
 170                OPT_BOOLEAN(0, "all", &all, "list all commits reachable from all refs"),
 171                OPT_BOOLEAN(0, "stdin", &transform_stdin, "read from stdin"),
 172                OPT_END(),
 173        };
 174
 175        git_config(git_default_config);
 176        argc = parse_options(argc, argv, opts, name_rev_usage, 0);
 177        if (!!all + !!transform_stdin + !!argc > 1) {
 178                error("Specify either a list, or --all, not both!");
 179                usage_with_options(name_rev_usage, opts);
 180        }
 181        if (all || transform_stdin)
 182                cutoff = 0;
 183
 184        for (; argc; argc--, argv++) {
 185                unsigned char sha1[20];
 186                struct object *o;
 187                struct commit *commit;
 188
 189                if (get_sha1(*argv, sha1)) {
 190                        fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 191                                        *argv);
 192                        continue;
 193                }
 194
 195                o = deref_tag(parse_object(sha1), *argv, 0);
 196                if (!o || o->type != OBJ_COMMIT) {
 197                        fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 198                                        *argv);
 199                        continue;
 200                }
 201
 202                commit = (struct commit *)o;
 203                if (cutoff > commit->date)
 204                        cutoff = commit->date;
 205                add_object_array((struct object *)commit, *argv, &revs);
 206        }
 207
 208        if (cutoff)
 209                cutoff = cutoff - CUTOFF_DATE_SLOP;
 210        for_each_ref(name_ref, &data);
 211
 212        if (transform_stdin) {
 213                char buffer[2048];
 214                char *p, *p_start;
 215
 216                while (!feof(stdin)) {
 217                        int forty = 0;
 218                        p = fgets(buffer, sizeof(buffer), stdin);
 219                        if (!p)
 220                                break;
 221
 222                        for (p_start = p; *p; p++) {
 223#define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 224                                if (!ishex(*p))
 225                                        forty = 0;
 226                                else if (++forty == 40 &&
 227                                                !ishex(*(p+1))) {
 228                                        unsigned char sha1[40];
 229                                        const char *name = "undefined";
 230                                        char c = *(p+1);
 231
 232                                        forty = 0;
 233
 234                                        *(p+1) = 0;
 235                                        if (!get_sha1(p - 39, sha1)) {
 236                                                struct object *o =
 237                                                        lookup_object(sha1);
 238                                                if (o)
 239                                                        name = get_rev_name(o);
 240                                        }
 241                                        *(p+1) = c;
 242
 243                                        if (!strcmp(name, "undefined"))
 244                                                continue;
 245
 246                                        fwrite(p_start, p - p_start + 1, 1,
 247                                               stdout);
 248                                        printf(" (%s)", name);
 249                                        p_start = p + 1;
 250                                }
 251                        }
 252
 253                        /* flush */
 254                        if (p_start != p)
 255                                fwrite(p_start, p - p_start, 1, stdout);
 256                }
 257        } else if (all) {
 258                int i, max;
 259
 260                max = get_max_object_index();
 261                for (i = 0; i < max; i++) {
 262                        struct object * obj = get_indexed_object(i);
 263                        if (!obj)
 264                                continue;
 265                        if (!data.name_only)
 266                                printf("%s ", sha1_to_hex(obj->sha1));
 267                        printf("%s\n", get_rev_name(obj));
 268                }
 269        } else {
 270                int i;
 271                for (i = 0; i < revs.nr; i++) {
 272                        if (!data.name_only)
 273                                printf("%s ", revs.objects[i].name);
 274                        printf("%s\n", get_rev_name(revs.objects[i].item));
 275                }
 276        }
 277
 278        return 0;
 279}