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         }
 154         else {
 155                 if (obj->flags & COMPLETE)
 156                         return 0;
 157                 prefetch(obj->sha1);
 158         }
 159
 160         object_list_insert(obj, process_queue_end);
 161         process_queue_end = &(*process_queue_end)->next;
 162         return 0;
 163 }
 164
 165 static int loop(void)
 166 {
 167         struct object_list *elem;
 168
 169         while (process_queue) {
 170                 struct object *obj = process_queue->item;
 171                 elem = process_queue;
 172                 process_queue = elem->next;
 173                 free(elem);
 174                 if (!process_queue)
 175                         process_queue_end = &process_queue;
 176
 177                 /* If we are not scanning this object, we placed it in
 178                  * the queue because we needed to fetch it first.
 179                  */
 180                 if (! (obj->flags & TO_SCAN)) {
 181                         if (fetch(obj->sha1)) {
 182                                 report_missing(obj->type
 183                                                ? obj->type
 184                                                : "object", obj->sha1);
 185                                 return -1;
 186                         }
 187                 }
 188                 if (!obj->type)
 189                         parse_object(obj->sha1);
 190                 if (process_object(obj))
 191                         return -1;
 192         }
 193         return 0;
 194 }
 195
 196 static int interpret_target(char *target, unsigned char *sha1)
 197 {
 198         if (!get_sha1_hex(target, sha1))
 199                 return 0;
 200         if (!check_ref_format(target)) {
 201                 if (!fetch_ref(target, sha1)) {
 202                         return 0;
 203                 }
 204         }
 205         return -1;
 206 }
 207
 208 static int mark_complete(const char *path, const unsigned char *sha1)
 209 {
 210         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 211         if (commit) {
 212                 commit->object.flags |= COMPLETE;
 213                 insert_by_date(commit, &complete);
 214         }
 215         return 0;
 216 }
 217
 218 int pull(char *target)
 219 {
 220         struct ref_lock *lock = NULL;
 221         unsigned char sha1[20];
 222         char *msg;
 223         int ret;
 224
 225         save_commit_buffer = 0;
 226         track_object_refs = 0;
 227         if (write_ref) {
 228                 lock = lock_ref_sha1(write_ref, NULL, 0);
 229                 if (!lock) {
 230                         error("Can't lock ref %s", write_ref);
 231                         return -1;
 232                 }
 233         }
 234
 235         if (!get_recover)
 236                 for_each_ref(mark_complete);
 237
 238         if (interpret_target(target, sha1)) {
 239                 error("Could not interpret %s as something to pull", target);
 240                 if (lock)
 241                         unlock_ref(lock);
 242                 return -1;
 243         }
 244         if (process(lookup_unknown_object(sha1))) {
 245                 if (lock)
 246                         unlock_ref(lock);
 247                 return -1;
 248         }
 249         if (loop()) {
 250                 if (lock)
 251                         unlock_ref(lock);
 252                 return -1;
 253         }
 254
 255         if (write_ref) {
 256                 if (write_ref_log_details) {
 257                         msg = xmalloc(strlen(write_ref_log_details) + 12);
 258                         sprintf(msg, "fetch from %s", write_ref_log_details);
 259                 }
 260                 else
 261                         msg = NULL;
 262                 ret = write_ref_sha1(lock, sha1, msg ? msg : "fetch (unknown)");
 263                 if (msg)
 264                         free(msg);
 265                 return ret;
 266         }
 267         return 0;
 268 }