walker.con commit git fetch-pack: do not complain about "no common commits" in an empty repo (ebcce31)
   1#include "cache.h"
   2#include "walker.h"
   3#include "commit.h"
   4#include "tree.h"
   5#include "tree-walk.h"
   6#include "tag.h"
   7#include "blob.h"
   8#include "refs.h"
   9
  10static unsigned char current_commit_sha1[20];
  11
  12void walker_say(struct walker *walker, const char *fmt, const char *hex)
  13{
  14        if (walker->get_verbosely)
  15                fprintf(stderr, fmt, hex);
  16}
  17
  18static void report_missing(const struct object *obj)
  19{
  20        char missing_hex[41];
  21        strcpy(missing_hex, sha1_to_hex(obj->sha1));;
  22        fprintf(stderr, "Cannot obtain needed %s %s\n",
  23                obj->type ? typename(obj->type): "object", missing_hex);
  24        if (!is_null_sha1(current_commit_sha1))
  25                fprintf(stderr, "while processing commit %s.\n",
  26                        sha1_to_hex(current_commit_sha1));
  27}
  28
  29static int process(struct walker *walker, struct object *obj);
  30
  31static int process_tree(struct walker *walker, struct tree *tree)
  32{
  33        struct tree_desc desc;
  34        struct name_entry entry;
  35
  36        if (parse_tree(tree))
  37                return -1;
  38
  39        init_tree_desc(&desc, tree->buffer, tree->size);
  40        while (tree_entry(&desc, &entry)) {
  41                struct object *obj = NULL;
  42
  43                /* submodule commits are not stored in the superproject */
  44                if (S_ISGITLINK(entry.mode))
  45                        continue;
  46                if (S_ISDIR(entry.mode)) {
  47                        struct tree *tree = lookup_tree(entry.sha1);
  48                        if (tree)
  49                                obj = &tree->object;
  50                }
  51                else {
  52                        struct blob *blob = lookup_blob(entry.sha1);
  53                        if (blob)
  54                                obj = &blob->object;
  55                }
  56                if (!obj || process(walker, obj))
  57                        return -1;
  58        }
  59        free(tree->buffer);
  60        tree->buffer = NULL;
  61        tree->size = 0;
  62        tree->object.parsed = 0;
  63        return 0;
  64}
  65
  66#define COMPLETE        (1U << 0)
  67#define SEEN            (1U << 1)
  68#define TO_SCAN         (1U << 2)
  69
  70static struct commit_list *complete = NULL;
  71
  72static int process_commit(struct walker *walker, struct commit *commit)
  73{
  74        if (parse_commit(commit))
  75                return -1;
  76
  77        while (complete && complete->item->date >= commit->date) {
  78                pop_most_recent_commit(&complete, COMPLETE);
  79        }
  80
  81        if (commit->object.flags & COMPLETE)
  82                return 0;
  83
  84        hashcpy(current_commit_sha1, commit->object.sha1);
  85
  86        walker_say(walker, "walk %s\n", sha1_to_hex(commit->object.sha1));
  87
  88        if (walker->get_tree) {
  89                if (process(walker, &commit->tree->object))
  90                        return -1;
  91                if (!walker->get_all)
  92                        walker->get_tree = 0;
  93        }
  94        if (walker->get_history) {
  95                struct commit_list *parents = commit->parents;
  96                for (; parents; parents = parents->next) {
  97                        if (process(walker, &parents->item->object))
  98                                return -1;
  99                }
 100        }
 101        return 0;
 102}
 103
 104static int process_tag(struct walker *walker, struct tag *tag)
 105{
 106        if (parse_tag(tag))
 107                return -1;
 108        return process(walker, tag->tagged);
 109}
 110
 111static struct object_list *process_queue = NULL;
 112static struct object_list **process_queue_end = &process_queue;
 113
 114static int process_object(struct walker *walker, struct object *obj)
 115{
 116        if (obj->type == OBJ_COMMIT) {
 117                if (process_commit(walker, (struct commit *)obj))
 118                        return -1;
 119                return 0;
 120        }
 121        if (obj->type == OBJ_TREE) {
 122                if (process_tree(walker, (struct tree *)obj))
 123                        return -1;
 124                return 0;
 125        }
 126        if (obj->type == OBJ_BLOB) {
 127                return 0;
 128        }
 129        if (obj->type == OBJ_TAG) {
 130                if (process_tag(walker, (struct tag *)obj))
 131                        return -1;
 132                return 0;
 133        }
 134        return error("Unable to determine requirements "
 135                     "of type %s for %s",
 136                     typename(obj->type), sha1_to_hex(obj->sha1));
 137}
 138
 139static int process(struct walker *walker, struct object *obj)
 140{
 141        if (obj->flags & SEEN)
 142                return 0;
 143        obj->flags |= SEEN;
 144
 145        if (has_sha1_file(obj->sha1)) {
 146                /* We already have it, so we should scan it now. */
 147                obj->flags |= TO_SCAN;
 148        }
 149        else {
 150                if (obj->flags & COMPLETE)
 151                        return 0;
 152                walker->prefetch(walker, obj->sha1);
 153        }
 154
 155        object_list_insert(obj, process_queue_end);
 156        process_queue_end = &(*process_queue_end)->next;
 157        return 0;
 158}
 159
 160static int loop(struct walker *walker)
 161{
 162        struct object_list *elem;
 163
 164        while (process_queue) {
 165                struct object *obj = process_queue->item;
 166                elem = process_queue;
 167                process_queue = elem->next;
 168                free(elem);
 169                if (!process_queue)
 170                        process_queue_end = &process_queue;
 171
 172                /* If we are not scanning this object, we placed it in
 173                 * the queue because we needed to fetch it first.
 174                 */
 175                if (! (obj->flags & TO_SCAN)) {
 176                        if (walker->fetch(walker, obj->sha1)) {
 177                                report_missing(obj);
 178                                return -1;
 179                        }
 180                }
 181                if (!obj->type)
 182                        parse_object(obj->sha1);
 183                if (process_object(walker, obj))
 184                        return -1;
 185        }
 186        return 0;
 187}
 188
 189static int interpret_target(struct walker *walker, char *target, unsigned char *sha1)
 190{
 191        if (!get_sha1_hex(target, sha1))
 192                return 0;
 193        if (!check_ref_format(target)) {
 194                struct ref *ref = alloc_ref_from_str(target);
 195                if (!walker->fetch_ref(walker, ref)) {
 196                        hashcpy(sha1, ref->old_sha1);
 197                        free(ref);
 198                        return 0;
 199                }
 200                free(ref);
 201        }
 202        return -1;
 203}
 204
 205static int mark_complete(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 206{
 207        struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 208        if (commit) {
 209                commit->object.flags |= COMPLETE;
 210                insert_by_date(commit, &complete);
 211        }
 212        return 0;
 213}
 214
 215int walker_targets_stdin(char ***target, const char ***write_ref)
 216{
 217        int targets = 0, targets_alloc = 0;
 218        struct strbuf buf;
 219        *target = NULL; *write_ref = NULL;
 220        strbuf_init(&buf, 0);
 221        while (1) {
 222                char *rf_one = NULL;
 223                char *tg_one;
 224
 225                if (strbuf_getline(&buf, stdin, '\n') == EOF)
 226                        break;
 227                tg_one = buf.buf;
 228                rf_one = strchr(tg_one, '\t');
 229                if (rf_one)
 230                        *rf_one++ = 0;
 231
 232                if (targets >= targets_alloc) {
 233                        targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
 234                        *target = xrealloc(*target, targets_alloc * sizeof(**target));
 235                        *write_ref = xrealloc(*write_ref, targets_alloc * sizeof(**write_ref));
 236                }
 237                (*target)[targets] = xstrdup(tg_one);
 238                (*write_ref)[targets] = rf_one ? xstrdup(rf_one) : NULL;
 239                targets++;
 240        }
 241        strbuf_release(&buf);
 242        return targets;
 243}
 244
 245void walker_targets_free(int targets, char **target, const char **write_ref)
 246{
 247        while (targets--) {
 248                free(target[targets]);
 249                if (write_ref && write_ref[targets])
 250                        free((char *) write_ref[targets]);
 251        }
 252}
 253
 254int walker_fetch(struct walker *walker, int targets, char **target,
 255                 const char **write_ref, const char *write_ref_log_details)
 256{
 257        struct ref_lock **lock = xcalloc(targets, sizeof(struct ref_lock *));
 258        unsigned char *sha1 = xmalloc(targets * 20);
 259        char *msg;
 260        int ret;
 261        int i;
 262
 263        save_commit_buffer = 0;
 264
 265        for (i = 0; i < targets; i++) {
 266                if (!write_ref || !write_ref[i])
 267                        continue;
 268
 269                lock[i] = lock_ref_sha1(write_ref[i], NULL);
 270                if (!lock[i]) {
 271                        error("Can't lock ref %s", write_ref[i]);
 272                        goto unlock_and_fail;
 273                }
 274        }
 275
 276        if (!walker->get_recover)
 277                for_each_ref(mark_complete, NULL);
 278
 279        for (i = 0; i < targets; i++) {
 280                if (interpret_target(walker, target[i], &sha1[20 * i])) {
 281                        error("Could not interpret response from server '%s' as something to pull", target[i]);
 282                        goto unlock_and_fail;
 283                }
 284                if (process(walker, lookup_unknown_object(&sha1[20 * i])))
 285                        goto unlock_and_fail;
 286        }
 287
 288        if (loop(walker))
 289                goto unlock_and_fail;
 290
 291        if (write_ref_log_details) {
 292                msg = xmalloc(strlen(write_ref_log_details) + 12);
 293                sprintf(msg, "fetch from %s", write_ref_log_details);
 294        } else {
 295                msg = NULL;
 296        }
 297        for (i = 0; i < targets; i++) {
 298                if (!write_ref || !write_ref[i])
 299                        continue;
 300                ret = write_ref_sha1(lock[i], &sha1[20 * i], msg ? msg : "fetch (unknown)");
 301                lock[i] = NULL;
 302                if (ret)
 303                        goto unlock_and_fail;
 304        }
 305        free(msg);
 306
 307        return 0;
 308
 309unlock_and_fail:
 310        for (i = 0; i < targets; i++)
 311                if (lock[i])
 312                        unlock_ref(lock[i]);
 313
 314        return -1;
 315}
 316
 317void walker_free(struct walker *walker)
 318{
 319        walker->cleanup(walker);
 320        free(walker);
 321}