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(entry.oid);
  53                         if (tree)
  54                                 obj = &tree->object;
  55                 }
  56                 else {
  57                         struct blob *blob = lookup_blob(entry.oid);
  58                         if (blob)
  59                                 obj = &blob->object;
  60                 }
  61                 if (!obj || process(walker, obj))
  62                         return -1;
  63         }
  64         free_tree_buffer(tree);
  65         return 0;
  66 }
  67
  68 /* Remember to update object flag allocation in object.h */
  69 #define COMPLETE        (1U << 0)
  70 #define SEEN            (1U << 1)
  71 #define TO_SCAN         (1U << 2)
  72
  73 static struct commit_list *complete = NULL;
  74
  75 static int process_commit(struct walker *walker, struct commit *commit)
  76 {
  77         struct commit_list *parents;
  78
  79         if (parse_commit(commit))
  80                 return -1;
  81
  82         while (complete && complete->item->date >= commit->date) {
  83                 pop_most_recent_commit(&complete, COMPLETE);
  84         }
  85
  86         if (commit->object.flags & COMPLETE)
  87                 return 0;
  88
  89         oidcpy(&current_commit_oid, &commit->object.oid);
  90
  91         walker_say(walker, "walk %s\n", oid_to_hex(&commit->object.oid));
  92
  93         if (process(walker, &get_commit_tree(commit)->object))
  94                 return -1;
  95
  96         for (parents = commit->parents; parents; parents = parents->next) {
  97                 if (process(walker, &parents->item->object))
  98                         return -1;
  99         }
 100
 101         return 0;
 102 }
 103
 104 static 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
 111 static struct object_list *process_queue = NULL;
 112 static struct object_list **process_queue_end = &process_queue;
 113
 114 static 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                      type_name(obj->type), oid_to_hex(&obj->oid));
 137 }
 138
 139 static 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_object_file(&obj->oid)) {
 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->oid.hash);
 153         }
 154
 155         object_list_insert(obj, process_queue_end);
 156         process_queue_end = &(*process_queue_end)->next;
 157         return 0;
 158 }
 159
 160 static 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->oid.hash)) {
 177                                 report_missing(obj);
 178                                 return -1;
 179                         }
 180                 }
 181                 if (!obj->type)
 182                         parse_object(the_repository, &obj->oid);
 183                 if (process_object(walker, obj))
 184                         return -1;
 185         }
 186         return 0;
 187 }
 188
 189 static int interpret_target(struct walker *walker, char *target, struct object_id *oid)
 190 {
 191         if (!get_oid_hex(target, oid))
 192                 return 0;
 193         if (!check_refname_format(target, 0)) {
 194                 struct ref *ref = alloc_ref(target);
 195                 if (!walker->fetch_ref(walker, ref)) {
 196                         oidcpy(oid, &ref->old_oid);
 197                         free(ref);
 198                         return 0;
 199                 }
 200                 free(ref);
 201         }
 202         return -1;
 203 }
 204
 205 static int mark_complete(const char *path, const struct object_id *oid,
 206                          int flag, void *cb_data)
 207 {
 208         struct commit *commit = lookup_commit_reference_gently(oid, 1);
 209
 210         if (commit) {
 211                 commit->object.flags |= COMPLETE;
 212                 commit_list_insert(commit, &complete);
 213         }
 214         return 0;
 215 }
 216
 217 int walker_targets_stdin(char ***target, const char ***write_ref)
 218 {
 219         int targets = 0, targets_alloc = 0;
 220         struct strbuf buf = STRBUF_INIT;
 221         *target = NULL; *write_ref = NULL;
 222         while (1) {
 223                 char *rf_one = NULL;
 224                 char *tg_one;
 225
 226                 if (strbuf_getline_lf(&buf, stdin) == EOF)
 227                         break;
 228                 tg_one = buf.buf;
 229                 rf_one = strchr(tg_one, '\t');
 230                 if (rf_one)
 231                         *rf_one++ = 0;
 232
 233                 if (targets >= targets_alloc) {
 234                         targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
 235                         REALLOC_ARRAY(*target, targets_alloc);
 236                         REALLOC_ARRAY(*write_ref, targets_alloc);
 237                 }
 238                 (*target)[targets] = xstrdup(tg_one);
 239                 (*write_ref)[targets] = xstrdup_or_null(rf_one);
 240                 targets++;
 241         }
 242         strbuf_release(&buf);
 243         return targets;
 244 }
 245
 246 void walker_targets_free(int targets, char **target, const char **write_ref)
 247 {
 248         while (targets--) {
 249                 free(target[targets]);
 250                 if (write_ref)
 251                         free((char *) write_ref[targets]);
 252         }
 253 }
 254
 255 int walker_fetch(struct walker *walker, int targets, char **target,
 256                  const char **write_ref, const char *write_ref_log_details)
 257 {
 258         struct strbuf refname = STRBUF_INIT;
 259         struct strbuf err = STRBUF_INIT;
 260         struct ref_transaction *transaction = NULL;
 261         struct object_id *oids = xmalloc(targets * sizeof(struct object_id));
 262         char *msg = NULL;
 263         int i, ret = -1;
 264
 265         save_commit_buffer = 0;
 266
 267         if (write_ref) {
 268                 transaction = ref_transaction_begin(&err);
 269                 if (!transaction) {
 270                         error("%s", err.buf);
 271                         goto done;
 272                 }
 273         }
 274
 275         if (!walker->get_recover) {
 276                 for_each_ref(mark_complete, NULL);
 277                 commit_list_sort_by_date(&complete);
 278         }
 279
 280         for (i = 0; i < targets; i++) {
 281                 if (interpret_target(walker, target[i], oids + i)) {
 282                         error("Could not interpret response from server '%s' as something to pull", target[i]);
 283                         goto done;
 284                 }
 285                 if (process(walker, lookup_unknown_object(oids[i].hash)))
 286                         goto done;
 287         }
 288
 289         if (loop(walker))
 290                 goto done;
 291         if (!write_ref) {
 292                 ret = 0;
 293                 goto done;
 294         }
 295         if (write_ref_log_details) {
 296                 msg = xstrfmt("fetch from %s", write_ref_log_details);
 297         } else {
 298                 msg = NULL;
 299         }
 300         for (i = 0; i < targets; i++) {
 301                 if (!write_ref[i])
 302                         continue;
 303                 strbuf_reset(&refname);
 304                 strbuf_addf(&refname, "refs/%s", write_ref[i]);
 305                 if (ref_transaction_update(transaction, refname.buf,
 306                                            oids + i, NULL, 0,
 307                                            msg ? msg : "fetch (unknown)",
 308                                            &err)) {
 309                         error("%s", err.buf);
 310                         goto done;
 311                 }
 312         }
 313         if (ref_transaction_commit(transaction, &err)) {
 314                 error("%s", err.buf);
 315                 goto done;
 316         }
 317
 318         ret = 0;
 319
 320 done:
 321         ref_transaction_free(transaction);
 322         free(msg);
 323         free(oids);
 324         strbuf_release(&err);
 325         strbuf_release(&refname);
 326         return ret;
 327 }
 328
 329 void walker_free(struct walker *walker)
 330 {
 331         walker->cleanup(walker);
 332         free(walker);
 333 }