walker.c

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