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 const char *write_ref = NULL;
  12 const char *write_ref_log_details = NULL;
  13
  14 int get_tree = 0;
  15 int get_history = 0;
  16 int get_all = 0;
  17 int get_verbosely = 0;
  18 int get_recover = 0;
  19 static unsigned char current_commit_sha1[20];
  20
  21 void pull_say(const char *fmt, const char *hex)
  22 {
  23         if (get_verbosely)
  24                 fprintf(stderr, fmt, hex);
  25 }
  26
  27 static void report_missing(const char *what, const unsigned char *missing)
  28 {
  29         char missing_hex[41];
  30
  31         strcpy(missing_hex, sha1_to_hex(missing));;
  32         fprintf(stderr,
  33                 "Cannot obtain needed %s %s\nwhile processing commit %s.\n",
  34                 what, missing_hex, sha1_to_hex(current_commit_sha1));
  35 }
  36
  37 static int process(struct object *obj);
  38
  39 static int process_tree(struct tree *tree)
  40 {
  41         struct tree_desc desc;
  42         struct name_entry entry;
  43
  44         if (parse_tree(tree))
  45                 return -1;
  46
  47         desc.buf = tree->buffer;
  48         desc.size = tree->size;
  49         while (tree_entry(&desc, &entry)) {
  50                 struct object *obj = NULL;
  51
  52                 if (S_ISDIR(entry.mode)) {
  53                         struct tree *tree = lookup_tree(entry.sha1);
  54                         if (tree)
  55                                 obj = &tree->object;
  56                 }
  57                 else {
  58                         struct blob *blob = lookup_blob(entry.sha1);
  59                         if (blob)
  60                                 obj = &blob->object;
  61                 }
  62                 if (!obj || process(obj))
  63                         return -1;
  64         }
  65         free(tree->buffer);
  66         tree->buffer = NULL;
  67         tree->size = 0;
  68         return 0;
  69 }
  70
  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 commit *commit)
  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         memcpy(current_commit_sha1, commit->object.sha1, 20);
  90
  91         pull_say("walk %s\n", sha1_to_hex(commit->object.sha1));
  92
  93         if (get_tree) {
  94                 if (process(&commit->tree->object))
  95                         return -1;
  96                 if (!get_all)
  97                         get_tree = 0;
  98         }
  99         if (get_history) {
 100                 struct commit_list *parents = commit->parents;
 101                 for (; parents; parents = parents->next) {
 102                         if (process(&parents->item->object))
 103                                 return -1;
 104                 }
 105         }
 106         return 0;
 107 }
 108
 109 static int process_tag(struct tag *tag)
 110 {
 111         if (parse_tag(tag))
 112                 return -1;
 113         return process(tag->tagged);
 114 }
 115
 116 static struct object_list *process_queue = NULL;
 117 static struct object_list **process_queue_end = &process_queue;
 118
 119 static int process_object(struct object *obj)
 120 {
 121         if (obj->type == commit_type) {
 122                 if (process_commit((struct commit *)obj))
 123                         return -1;
 124                 return 0;
 125         }
 126         if (obj->type == tree_type) {
 127                 if (process_tree((struct tree *)obj))
 128                         return -1;
 129                 return 0;
 130         }
 131         if (obj->type == blob_type) {
 132                 return 0;
 133         }
 134         if (obj->type == tag_type) {
 135                 if (process_tag((struct tag *)obj))
 136                         return -1;
 137                 return 0;
 138         }
 139         return error("Unable to determine requirements "
 140                      "of type %s for %s",
 141                      obj->type, sha1_to_hex(obj->sha1));
 142 }
 143
 144 static int process(struct object *obj)
 145 {
 146         if (obj->flags & SEEN)
 147                 return 0;
 148         obj->flags |= SEEN;
 149
 150         if (has_sha1_file(obj->sha1)) {
 151                 /* We already have it, so we should scan it now. */
 152                 obj->flags |= TO_SCAN;
 153         } else {
 154                 if (obj->flags & COMPLETE)
 155                         return 0;
 156                 prefetch(obj->sha1);
 157         }
 158
 159         object_list_insert(obj, process_queue_end);
 160         process_queue_end = &(*process_queue_end)->next;
 161         return 0;
 162 }
 163
 164 static int loop(void)
 165 {
 166         struct object_list *elem;
 167
 168         while (process_queue) {
 169                 struct object *obj = process_queue->item;
 170                 elem = process_queue;
 171                 process_queue = elem->next;
 172                 free(elem);
 173                 if (!process_queue)
 174                         process_queue_end = &process_queue;
 175
 176                 /* If we are not scanning this object, we placed it in
 177                  * the queue because we needed to fetch it first.
 178                  */
 179                 if (! (obj->flags & TO_SCAN)) {
 180                         if (fetch(obj->sha1)) {
 181                                 report_missing(obj->type
 182                                                ? obj->type
 183                                                : "object", obj->sha1);
 184                                 return -1;
 185                         }
 186                 }
 187                 if (!obj->type)
 188                         parse_object(obj->sha1);
 189                 if (process_object(obj))
 190                         return -1;
 191         }
 192         return 0;
 193 }
 194
 195 static int interpret_target(char *target, unsigned char *sha1)
 196 {
 197         if (!get_sha1_hex(target, sha1))
 198                 return 0;
 199         if (!check_ref_format(target)) {
 200                 if (!fetch_ref(target, sha1)) {
 201                         return 0;
 202                 }
 203         }
 204         return -1;
 205 }
 206
 207 static int mark_complete(const char *path, const unsigned char *sha1)
 208 {
 209         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 210         if (commit) {
 211                 commit->object.flags |= COMPLETE;
 212                 insert_by_date(commit, &complete);
 213         }
 214         return 0;
 215 }
 216
 217 int pull(char *target)
 218 {
 219         struct ref_lock *lock = NULL;
 220         unsigned char sha1[20];
 221         char *msg;
 222         int ret;
 223
 224         save_commit_buffer = 0;
 225         track_object_refs = 0;
 226         if (write_ref) {
 227                 lock = lock_ref_sha1(write_ref, NULL, 0);
 228                 if (!lock) {
 229                         error("Can't lock ref %s", write_ref);
 230                         return -1;
 231                 }
 232         }
 233
 234         if (!get_recover)
 235                 for_each_ref(mark_complete);
 236
 237         if (interpret_target(target, sha1)) {
 238                 error("Could not interpret %s as something to pull", target);
 239                 if (lock)
 240                         unlock_ref(lock);
 241                 return -1;
 242         }
 243         if (process(lookup_unknown_object(sha1))) {
 244                 if (lock)
 245                         unlock_ref(lock);
 246                 return -1;
 247         }
 248         if (loop()) {
 249                 if (lock)
 250                         unlock_ref(lock);
 251                 return -1;
 252         }
 253
 254         if (write_ref) {
 255                 if (write_ref_log_details) {
 256                         msg = xmalloc(strlen(write_ref_log_details) + 12);
 257                         sprintf(msg, "fetch from %s", write_ref_log_details);
 258                 } else
 259                         msg = NULL;
 260                 ret = write_ref_sha1(lock, sha1, msg ? msg : "fetch (unknown)");
 261                 if (msg)
 262                         free(msg);
 263                 return ret;
 264         }
 265         return 0;
 266 }