fetch.c

   1 #include "fetch.h"
   2
   3 #include "cache.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 int get_tree = 0;
  12 int get_history = 0;
  13 int get_all = 0;
  14 int get_verbosely = 0;
  15 int get_recover = 0;
  16 static unsigned char current_commit_sha1[20];
  17
  18 void pull_say(const char *fmt, const char *hex)
  19 {
  20         if (get_verbosely)
  21                 fprintf(stderr, fmt, hex);
  22 }
  23
  24 static void report_missing(const char *what, const unsigned char *missing)
  25 {
  26         char missing_hex[41];
  27
  28         strcpy(missing_hex, sha1_to_hex(missing));;
  29         fprintf(stderr,
  30                 "Cannot obtain needed %s %s\nwhile processing commit %s.\n",
  31                 what, missing_hex, sha1_to_hex(current_commit_sha1));
  32 }
  33
  34 static int process(struct object *obj);
  35
  36 static int process_tree(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         desc.buf = tree->buffer;
  45         desc.size = tree->size;
  46         while (tree_entry(&desc, &entry)) {
  47                 struct object *obj = NULL;
  48
  49                 if (S_ISDIR(entry.mode)) {
  50                         struct tree *tree = lookup_tree(entry.sha1);
  51                         if (tree)
  52                                 obj = &tree->object;
  53                 }
  54                 else {
  55                         struct blob *blob = lookup_blob(entry.sha1);
  56                         if (blob)
  57                                 obj = &blob->object;
  58                 }
  59                 if (!obj || process(obj))
  60                         return -1;
  61         }
  62         free(tree->buffer);
  63         tree->buffer = NULL;
  64         tree->size = 0;
  65         return 0;
  66 }
  67
  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 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         memcpy(current_commit_sha1, commit->object.sha1, 20);
  87
  88         pull_say("walk %s\n", sha1_to_hex(commit->object.sha1));
  89
  90         if (get_tree) {
  91                 if (process(&commit->tree->object))
  92                         return -1;
  93                 if (!get_all)
  94                         get_tree = 0;
  95         }
  96         if (get_history) {
  97                 struct commit_list *parents = commit->parents;
  98                 for (; parents; parents = parents->next) {
  99                         if (process(&parents->item->object))
 100                                 return -1;
 101                 }
 102         }
 103         return 0;
 104 }
 105
 106 static int process_tag(struct tag *tag)
 107 {
 108         if (parse_tag(tag))
 109                 return -1;
 110         return process(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 object *obj)
 117 {
 118         if (obj->type == OBJ_COMMIT) {
 119                 if (process_commit((struct commit *)obj))
 120                         return -1;
 121                 return 0;
 122         }
 123         if (obj->type == OBJ_TREE) {
 124                 if (process_tree((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((struct tag *)obj))
 133                         return -1;
 134                 return 0;
 135         }
 136         return error("Unable to determine requirements "
 137                      "of type %s for %s",
 138                      typename(obj->type), sha1_to_hex(obj->sha1));
 139 }
 140
 141 static int process(struct object *obj)
 142 {
 143         if (obj->flags & SEEN)
 144                 return 0;
 145         obj->flags |= SEEN;
 146
 147         if (has_sha1_file(obj->sha1)) {
 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                 prefetch(obj->sha1);
 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(void)
 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 (fetch(obj->sha1)) {
 179                                 report_missing(typename(obj->type), obj->sha1);
 180                                 return -1;
 181                         }
 182                 }
 183                 if (!obj->type)
 184                         parse_object(obj->sha1);
 185                 if (process_object(obj))
 186                         return -1;
 187         }
 188         return 0;
 189 }
 190
 191 static int interpret_target(char *target, unsigned char *sha1)
 192 {
 193         if (!get_sha1_hex(target, sha1))
 194                 return 0;
 195         if (!check_ref_format(target)) {
 196                 if (!fetch_ref(target, sha1)) {
 197                         return 0;
 198                 }
 199         }
 200         return -1;
 201 }
 202
 203 static int mark_complete(const char *path, const unsigned char *sha1)
 204 {
 205         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 206         if (commit) {
 207                 commit->object.flags |= COMPLETE;
 208                 insert_by_date(commit, &complete);
 209         }
 210         return 0;
 211 }
 212
 213 int pull(char *target, const char *write_ref,
 214          const char *write_ref_log_details)
 215 {
 216         struct ref_lock *lock = NULL;
 217         unsigned char sha1[20];
 218         char *msg;
 219         int ret;
 220
 221         save_commit_buffer = 0;
 222         track_object_refs = 0;
 223         if (write_ref) {
 224                 lock = lock_ref_sha1(write_ref, NULL, 0);
 225                 if (!lock) {
 226                         error("Can't lock ref %s", write_ref);
 227                         return -1;
 228                 }
 229         }
 230
 231         if (!get_recover)
 232                 for_each_ref(mark_complete);
 233
 234         if (interpret_target(target, sha1)) {
 235                 error("Could not interpret %s as something to pull", target);
 236                 if (lock)
 237                         unlock_ref(lock);
 238                 return -1;
 239         }
 240         if (process(lookup_unknown_object(sha1))) {
 241                 if (lock)
 242                         unlock_ref(lock);
 243                 return -1;
 244         }
 245         if (loop()) {
 246                 if (lock)
 247                         unlock_ref(lock);
 248                 return -1;
 249         }
 250
 251         if (write_ref) {
 252                 if (write_ref_log_details) {
 253                         msg = xmalloc(strlen(write_ref_log_details) + 12);
 254                         sprintf(msg, "fetch from %s", write_ref_log_details);
 255                 }
 256                 else
 257                         msg = NULL;
 258                 ret = write_ref_sha1(lock, sha1, msg ? msg : "fetch (unknown)");
 259                 if (msg)
 260                         free(msg);
 261                 return ret;
 262         }
 263         return 0;
 264 }