walker.c

   1 #include "cache.h"
   2 #include "walker.h"
   3 #include "repository.h"
   4 #include "object-store.h"
   5 #include "commit.h"
   6 #include "tree.h"
   7 #include "tree-walk.h"
   8 #include "tag.h"
   9 #include "blob.h"
  10 #include "refs.h"
  11
  12 static struct object_id current_commit_oid;
  13
  14 void walker_say(struct walker *walker, const char *fmt, ...)
  15 {
  16         if (walker->get_verbosely) {
  17                 va_list ap;
  18                 va_start(ap, fmt);
  19                 vfprintf(stderr, fmt, ap);
  20                 va_end(ap);
  21         }
  22 }
  23
  24 static void report_missing(const struct object *obj)
  25 {
  26         fprintf(stderr, "Cannot obtain needed %s %s\n",
  27                 obj->type ? type_name(obj->type): "object",
  28                 oid_to_hex(&obj->oid));
  29         if (!is_null_oid(&current_commit_oid))
  30                 fprintf(stderr, "while processing commit %s.\n",
  31                         oid_to_hex(&current_commit_oid));
  32 }
  33
  34 static int process(struct walker *walker, struct object *obj);
  35
  36 static int process_tree(struct walker *walker, struct tree *tree)
  37 {
  38         struct tree_desc desc;
  39         struct name_entry entry;
  40
  41         if (parse_tree(tree))
  42                 return -1;
  43
  44         init_tree_desc(&desc, tree->buffer, tree->size);
  45         while (tree_entry(&desc, &entry)) {
  46                 struct object *obj = NULL;
  47
  48                 /* submodule commits are not stored in the superproject */
  49                 if (S_ISGITLINK(entry.mode))
  50                         continue;
  51                 if (S_ISDIR(entry.mode)) {
  52                         struct tree *tree = lookup_tree(the_repository,
  53                                                         &entry.oid);
  54                         if (tree)
  55                                 obj = &tree->object;
  56                 }
  57                 else {
  58                         struct blob *blob = lookup_blob(the_repository,
  59                                                         &entry.oid);
  60                         if (blob)
  61                                 obj = &blob->object;
  62                 }
  63                 if (!obj || process(walker, obj))
  64                         return -1;
  65         }
  66         free_tree_buffer(tree);
  67         return 0;
  68 }
  69
  70 /* Remember to update object flag allocation in object.h */
  71 #define COMPLETE        (1U << 0)
  72 #define SEEN            (1U << 1)
  73 #define TO_SCAN         (1U << 2)
  74
  75 static struct commit_list *complete = NULL;
  76
  77 static int process_commit(struct walker *walker, struct commit *commit)
  78 {
  79         struct commit_list *parents;
  80
  81         if (parse_commit(commit))
  82                 return -1;
  83
  84         while (complete && complete->item->date >= commit->date) {
  85                 pop_most_recent_commit(&complete, COMPLETE);
  86         }
  87
  88         if (commit->object.flags & COMPLETE)
  89                 return 0;
  90
  91         oidcpy(&current_commit_oid, &commit->object.oid);
  92
  93         walker_say(walker, "walk %s\n", oid_to_hex(&commit->object.oid));
  94
  95         if (process(walker, &get_commit_tree(commit)->object))
  96                 return -1;
  97
  98         for (parents = commit->parents; 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(the_repository, &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(the_repository,
 211                                                                oid, 1);
 212
 213         if (commit) {
 214                 commit->object.flags |= COMPLETE;
 215                 commit_list_insert(commit, &complete);
 216         }
 217         return 0;
 218 }
 219
 220 int walker_targets_stdin(char ***target, const char ***write_ref)
 221 {
 222         int targets = 0, targets_alloc = 0;
 223         struct strbuf buf = STRBUF_INIT;
 224         *target = NULL; *write_ref = NULL;
 225         while (1) {
 226                 char *rf_one = NULL;
 227                 char *tg_one;
 228
 229                 if (strbuf_getline_lf(&buf, stdin) == EOF)
 230                         break;
 231                 tg_one = buf.buf;
 232                 rf_one = strchr(tg_one, '\t');
 233                 if (rf_one)
 234                         *rf_one++ = 0;
 235
 236                 if (targets >= targets_alloc) {
 237                         targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
 238                         REALLOC_ARRAY(*target, targets_alloc);
 239                         REALLOC_ARRAY(*write_ref, targets_alloc);
 240                 }
 241                 (*target)[targets] = xstrdup(tg_one);
 242                 (*write_ref)[targets] = xstrdup_or_null(rf_one);
 243                 targets++;
 244         }
 245         strbuf_release(&buf);
 246         return targets;
 247 }
 248
 249 void walker_targets_free(int targets, char **target, const char **write_ref)
 250 {
 251         while (targets--) {
 252                 free(target[targets]);
 253                 if (write_ref)
 254                         free((char *) write_ref[targets]);
 255         }
 256 }
 257
 258 int walker_fetch(struct walker *walker, int targets, char **target,
 259                  const char **write_ref, const char *write_ref_log_details)
 260 {
 261         struct strbuf refname = STRBUF_INIT;
 262         struct strbuf err = STRBUF_INIT;
 263         struct ref_transaction *transaction = NULL;
 264         struct object_id *oids = xmalloc(targets * sizeof(struct object_id));
 265         char *msg = NULL;
 266         int i, ret = -1;
 267
 268         save_commit_buffer = 0;
 269
 270         if (write_ref) {
 271                 transaction = ref_transaction_begin(&err);
 272                 if (!transaction) {
 273                         error("%s", err.buf);
 274                         goto done;
 275                 }
 276         }
 277
 278         if (!walker->get_recover) {
 279                 for_each_ref(mark_complete, NULL);
 280                 commit_list_sort_by_date(&complete);
 281         }
 282
 283         for (i = 0; i < targets; i++) {
 284                 if (interpret_target(walker, target[i], oids + i)) {
 285                         error("Could not interpret response from server '%s' as something to pull", target[i]);
 286                         goto done;
 287                 }
 288                 if (process(walker, lookup_unknown_object(&oids[i])))
 289                         goto done;
 290         }
 291
 292         if (loop(walker))
 293                 goto done;
 294         if (!write_ref) {
 295                 ret = 0;
 296                 goto done;
 297         }
 298         if (write_ref_log_details) {
 299                 msg = xstrfmt("fetch from %s", write_ref_log_details);
 300         } else {
 301                 msg = NULL;
 302         }
 303         for (i = 0; i < targets; i++) {
 304                 if (!write_ref[i])
 305                         continue;
 306                 strbuf_reset(&refname);
 307                 strbuf_addf(&refname, "refs/%s", write_ref[i]);
 308                 if (ref_transaction_update(transaction, refname.buf,
 309                                            oids + i, NULL, 0,
 310                                            msg ? msg : "fetch (unknown)",
 311                                            &err)) {
 312                         error("%s", err.buf);
 313                         goto done;
 314                 }
 315         }
 316         if (ref_transaction_commit(transaction, &err)) {
 317                 error("%s", err.buf);
 318                 goto done;
 319         }
 320
 321         ret = 0;
 322
 323 done:
 324         ref_transaction_free(transaction);
 325         free(msg);
 326         free(oids);
 327         strbuf_release(&err);
 328         strbuf_release(&refname);
 329         return ret;
 330 }
 331
 332 void walker_free(struct walker *walker)
 333 {
 334         walker->cleanup(walker);
 335         free(walker);
 336 }