walker.c

   1 #include "cache.h"
   2 #include "walker.h"
   3 #include "object-store.h"
   4 #include "commit.h"
   5 #include "tree.h"
   6 #include "tree-walk.h"
   7 #include "tag.h"
   8 #include "blob.h"
   9 #include "refs.h"
  10
  11 static struct object_id current_commit_oid;
  12
  13 void walker_say(struct walker *walker, const char *fmt, ...)
  14 {
  15         if (walker->get_verbosely) {
  16                 va_list ap;
  17                 va_start(ap, fmt);
  18                 vfprintf(stderr, fmt, ap);
  19                 va_end(ap);
  20         }
  21 }
  22
  23 static void report_missing(const struct object *obj)
  24 {
  25         fprintf(stderr, "Cannot obtain needed %s %s\n",
  26                 obj->type ? type_name(obj->type): "object",
  27                 oid_to_hex(&obj->oid));
  28         if (!is_null_oid(&current_commit_oid))
  29                 fprintf(stderr, "while processing commit %s.\n",
  30                         oid_to_hex(&current_commit_oid));
  31 }
  32
  33 static int process(struct walker *walker, struct object *obj);
  34
  35 static int process_tree(struct walker *walker, struct tree *tree)
  36 {
  37         struct tree_desc desc;
  38         struct name_entry entry;
  39
  40         if (parse_tree(tree))
  41                 return -1;
  42
  43         init_tree_desc(&desc, tree->buffer, tree->size);
  44         while (tree_entry(&desc, &entry)) {
  45                 struct object *obj = NULL;
  46
  47                 /* submodule commits are not stored in the superproject */
  48                 if (S_ISGITLINK(entry.mode))
  49                         continue;
  50                 if (S_ISDIR(entry.mode)) {
  51                         struct tree *tree = lookup_tree(entry.oid);
  52                         if (tree)
  53                                 obj = &tree->object;
  54                 }
  55                 else {
  56                         struct blob *blob = lookup_blob(entry.oid);
  57                         if (blob)
  58                                 obj = &blob->object;
  59                 }
  60                 if (!obj || process(walker, obj))
  61                         return -1;
  62         }
  63         free_tree_buffer(tree);
  64         return 0;
  65 }
  66
  67 /* Remember to update object flag allocation in object.h */
  68 #define COMPLETE        (1U << 0)
  69 #define SEEN            (1U << 1)
  70 #define TO_SCAN         (1U << 2)
  71
  72 static struct commit_list *complete = NULL;
  73
  74 static int process_commit(struct walker *walker, struct commit *commit)
  75 {
  76         if (parse_commit(commit))
  77                 return -1;
  78
  79         while (complete && complete->item->date >= commit->date) {
  80                 pop_most_recent_commit(&complete, COMPLETE);
  81         }
  82
  83         if (commit->object.flags & COMPLETE)
  84                 return 0;
  85
  86         oidcpy(&current_commit_oid, &commit->object.oid);
  87
  88         walker_say(walker, "walk %s\n", oid_to_hex(&commit->object.oid));
  89
  90         if (walker->get_tree) {
  91                 if (process(walker, &commit->tree->object))
  92                         return -1;
  93                 if (!walker->get_all)
  94                         walker->get_tree = 0;
  95         }
  96         if (walker->get_history) {
  97                 struct commit_list *parents = commit->parents;
  98                 for (; parents; parents = parents->next) {
  99                         if (process(walker, &parents->item->object))
 100                                 return -1;
 101                 }
 102         }
 103         return 0;
 104 }
 105
 106 static int process_tag(struct walker *walker, struct tag *tag)
 107 {
 108         if (parse_tag(tag))
 109                 return -1;
 110         return process(walker, tag->tagged);
 111 }
 112
 113 static struct object_list *process_queue = NULL;
 114 static struct object_list **process_queue_end = &process_queue;
 115
 116 static int process_object(struct walker *walker, struct object *obj)
 117 {
 118         if (obj->type == OBJ_COMMIT) {
 119                 if (process_commit(walker, (struct commit *)obj))
 120                         return -1;
 121                 return 0;
 122         }
 123         if (obj->type == OBJ_TREE) {
 124                 if (process_tree(walker, (struct tree *)obj))
 125                         return -1;
 126                 return 0;
 127         }
 128         if (obj->type == OBJ_BLOB) {
 129                 return 0;
 130         }
 131         if (obj->type == OBJ_TAG) {
 132                 if (process_tag(walker, (struct tag *)obj))
 133                         return -1;
 134                 return 0;
 135         }
 136         return error("Unable to determine requirements "
 137                      "of type %s for %s",
 138                      type_name(obj->type), oid_to_hex(&obj->oid));
 139 }
 140
 141 static int process(struct walker *walker, struct object *obj)
 142 {
 143         if (obj->flags & SEEN)
 144                 return 0;
 145         obj->flags |= SEEN;
 146
 147         if (has_object_file(&obj->oid)) {
 148                 /* We already have it, so we should scan it now. */
 149                 obj->flags |= TO_SCAN;
 150         }
 151         else {
 152                 if (obj->flags & COMPLETE)
 153                         return 0;
 154                 walker->prefetch(walker, obj->oid.hash);
 155         }
 156
 157         object_list_insert(obj, process_queue_end);
 158         process_queue_end = &(*process_queue_end)->next;
 159         return 0;
 160 }
 161
 162 static int loop(struct walker *walker)
 163 {
 164         struct object_list *elem;
 165
 166         while (process_queue) {
 167                 struct object *obj = process_queue->item;
 168                 elem = process_queue;
 169                 process_queue = elem->next;
 170                 free(elem);
 171                 if (!process_queue)
 172                         process_queue_end = &process_queue;
 173
 174                 /* If we are not scanning this object, we placed it in
 175                  * the queue because we needed to fetch it first.
 176                  */
 177                 if (! (obj->flags & TO_SCAN)) {
 178                         if (walker->fetch(walker, obj->oid.hash)) {
 179                                 report_missing(obj);
 180                                 return -1;
 181                         }
 182                 }
 183                 if (!obj->type)
 184                         parse_object(&obj->oid);
 185                 if (process_object(walker, obj))
 186                         return -1;
 187         }
 188         return 0;
 189 }
 190
 191 static int interpret_target(struct walker *walker, char *target, struct object_id *oid)
 192 {
 193         if (!get_oid_hex(target, oid))
 194                 return 0;
 195         if (!check_refname_format(target, 0)) {
 196                 struct ref *ref = alloc_ref(target);
 197                 if (!walker->fetch_ref(walker, ref)) {
 198                         oidcpy(oid, &ref->old_oid);
 199                         free(ref);
 200                         return 0;
 201                 }
 202                 free(ref);
 203         }
 204         return -1;
 205 }
 206
 207 static int mark_complete(const char *path, const struct object_id *oid,
 208                          int flag, void *cb_data)
 209 {
 210         struct commit *commit = lookup_commit_reference_gently(oid, 1);
 211
 212         if (commit) {
 213                 commit->object.flags |= COMPLETE;
 214                 commit_list_insert(commit, &complete);
 215         }
 216         return 0;
 217 }
 218
 219 int walker_targets_stdin(char ***target, const char ***write_ref)
 220 {
 221         int targets = 0, targets_alloc = 0;
 222         struct strbuf buf = STRBUF_INIT;
 223         *target = NULL; *write_ref = NULL;
 224         while (1) {
 225                 char *rf_one = NULL;
 226                 char *tg_one;
 227
 228                 if (strbuf_getline_lf(&buf, stdin) == EOF)
 229                         break;
 230                 tg_one = buf.buf;
 231                 rf_one = strchr(tg_one, '\t');
 232                 if (rf_one)
 233                         *rf_one++ = 0;
 234
 235                 if (targets >= targets_alloc) {
 236                         targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
 237                         REALLOC_ARRAY(*target, targets_alloc);
 238                         REALLOC_ARRAY(*write_ref, targets_alloc);
 239                 }
 240                 (*target)[targets] = xstrdup(tg_one);
 241                 (*write_ref)[targets] = xstrdup_or_null(rf_one);
 242                 targets++;
 243         }
 244         strbuf_release(&buf);
 245         return targets;
 246 }
 247
 248 void walker_targets_free(int targets, char **target, const char **write_ref)
 249 {
 250         while (targets--) {
 251                 free(target[targets]);
 252                 if (write_ref)
 253                         free((char *) write_ref[targets]);
 254         }
 255 }
 256
 257 int walker_fetch(struct walker *walker, int targets, char **target,
 258                  const char **write_ref, const char *write_ref_log_details)
 259 {
 260         struct strbuf refname = STRBUF_INIT;
 261         struct strbuf err = STRBUF_INIT;
 262         struct ref_transaction *transaction = NULL;
 263         struct object_id *oids = xmalloc(targets * sizeof(struct object_id));
 264         char *msg = NULL;
 265         int i, ret = -1;
 266
 267         save_commit_buffer = 0;
 268
 269         if (write_ref) {
 270                 transaction = ref_transaction_begin(&err);
 271                 if (!transaction) {
 272                         error("%s", err.buf);
 273                         goto done;
 274                 }
 275         }
 276
 277         if (!walker->get_recover) {
 278                 for_each_ref(mark_complete, NULL);
 279                 commit_list_sort_by_date(&complete);
 280         }
 281
 282         for (i = 0; i < targets; i++) {
 283                 if (interpret_target(walker, target[i], oids + i)) {
 284                         error("Could not interpret response from server '%s' as something to pull", target[i]);
 285                         goto done;
 286                 }
 287                 if (process(walker, lookup_unknown_object(oids[i].hash)))
 288                         goto done;
 289         }
 290
 291         if (loop(walker))
 292                 goto done;
 293         if (!write_ref) {
 294                 ret = 0;
 295                 goto done;
 296         }
 297         if (write_ref_log_details) {
 298                 msg = xstrfmt("fetch from %s", write_ref_log_details);
 299         } else {
 300                 msg = NULL;
 301         }
 302         for (i = 0; i < targets; i++) {
 303                 if (!write_ref[i])
 304                         continue;
 305                 strbuf_reset(&refname);
 306                 strbuf_addf(&refname, "refs/%s", write_ref[i]);
 307                 if (ref_transaction_update(transaction, refname.buf,
 308                                            oids + i, NULL, 0,
 309                                            msg ? msg : "fetch (unknown)",
 310                                            &err)) {
 311                         error("%s", err.buf);
 312                         goto done;
 313                 }
 314         }
 315         if (ref_transaction_commit(transaction, &err)) {
 316                 error("%s", err.buf);
 317                 goto done;
 318         }
 319
 320         ret = 0;
 321
 322 done:
 323         ref_transaction_free(transaction);
 324         free(msg);
 325         free(oids);
 326         strbuf_release(&err);
 327         strbuf_release(&refname);
 328         return ret;
 329 }
 330
 331 void walker_free(struct walker *walker)
 332 {
 333         walker->cleanup(walker);
 334         free(walker);
 335 }