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                 if (S_ISDIR(entry.mode)) {
  51                         struct tree *tree = lookup_tree(entry.sha1);
  52                         process_tree(tree);
  53                 } else {
  54                         struct blob *blob = lookup_blob(entry.sha1);
  55                         process(&blob->object);
  56                 }
  57         }
  58         free(tree->buffer);
  59         tree->buffer = NULL;
  60         tree->size = 0;
  61         return 0;
  62 }
  63
  64 #define COMPLETE        (1U << 0)
  65 #define SEEN            (1U << 1)
  66 #define TO_SCAN         (1U << 2)
  67
  68 static struct commit_list *complete = NULL;
  69
  70 static int process_commit(struct commit *commit)
  71 {
  72         if (parse_commit(commit))
  73                 return -1;
  74
  75         while (complete && complete->item->date >= commit->date) {
  76                 pop_most_recent_commit(&complete, COMPLETE);
  77         }
  78
  79         if (commit->object.flags & COMPLETE)
  80                 return 0;
  81
  82         memcpy(current_commit_sha1, commit->object.sha1, 20);
  83
  84         pull_say("walk %s\n", sha1_to_hex(commit->object.sha1));
  85
  86         if (get_tree) {
  87                 if (process(&commit->tree->object))
  88                         return -1;
  89                 if (!get_all)
  90                         get_tree = 0;
  91         }
  92         if (get_history) {
  93                 struct commit_list *parents = commit->parents;
  94                 for (; parents; parents = parents->next) {
  95                         if (process(&parents->item->object))
  96                                 return -1;
  97                 }
  98         }
  99         return 0;
 100 }
 101
 102 static int process_tag(struct tag *tag)
 103 {
 104         if (parse_tag(tag))
 105                 return -1;
 106         return process(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 object *obj)
 113 {
 114         if (obj->type == commit_type) {
 115                 if (process_commit((struct commit *)obj))
 116                         return -1;
 117                 return 0;
 118         }
 119         if (obj->type == tree_type) {
 120                 if (process_tree((struct tree *)obj))
 121                         return -1;
 122                 return 0;
 123         }
 124         if (obj->type == blob_type) {
 125                 return 0;
 126         }
 127         if (obj->type == tag_type) {
 128                 if (process_tag((struct tag *)obj))
 129                         return -1;
 130                 return 0;
 131         }
 132         return error("Unable to determine requirements "
 133                      "of type %s for %s",
 134                      obj->type, sha1_to_hex(obj->sha1));
 135 }
 136
 137 static int process(struct object *obj)
 138 {
 139         if (obj->flags & SEEN)
 140                 return 0;
 141         obj->flags |= SEEN;
 142
 143         if (has_sha1_file(obj->sha1)) {
 144                 /* We already have it, so we should scan it now. */
 145                 obj->flags |= TO_SCAN;
 146         } else {
 147                 if (obj->flags & COMPLETE)
 148                         return 0;
 149                 prefetch(obj->sha1);
 150         }
 151
 152         object_list_insert(obj, process_queue_end);
 153         process_queue_end = &(*process_queue_end)->next;
 154         return 0;
 155 }
 156
 157 static int loop(void)
 158 {
 159         struct object_list *elem;
 160
 161         while (process_queue) {
 162                 struct object *obj = process_queue->item;
 163                 elem = process_queue;
 164                 process_queue = elem->next;
 165                 free(elem);
 166                 if (!process_queue)
 167                         process_queue_end = &process_queue;
 168
 169                 /* If we are not scanning this object, we placed it in
 170                  * the queue because we needed to fetch it first.
 171                  */
 172                 if (! (obj->flags & TO_SCAN)) {
 173                         if (fetch(obj->sha1)) {
 174                                 report_missing(obj->type
 175                                                ? obj->type
 176                                                : "object", obj->sha1);
 177                                 return -1;
 178                         }
 179                 }
 180                 if (!obj->type)
 181                         parse_object(obj->sha1);
 182                 if (process_object(obj))
 183                         return -1;
 184         }
 185         return 0;
 186 }
 187
 188 static int interpret_target(char *target, unsigned char *sha1)
 189 {
 190         if (!get_sha1_hex(target, sha1))
 191                 return 0;
 192         if (!check_ref_format(target)) {
 193                 if (!fetch_ref(target, sha1)) {
 194                         return 0;
 195                 }
 196         }
 197         return -1;
 198 }
 199
 200 static int mark_complete(const char *path, const unsigned char *sha1)
 201 {
 202         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
 203         if (commit) {
 204                 commit->object.flags |= COMPLETE;
 205                 insert_by_date(commit, &complete);
 206         }
 207         return 0;
 208 }
 209
 210 int pull(char *target)
 211 {
 212         struct ref_lock *lock = NULL;
 213         unsigned char sha1[20];
 214         char *msg;
 215         int ret;
 216
 217         save_commit_buffer = 0;
 218         track_object_refs = 0;
 219         if (write_ref) {
 220                 lock = lock_ref_sha1(write_ref, NULL, 0);
 221                 if (!lock) {
 222                         error("Can't lock ref %s", write_ref);
 223                         return -1;
 224                 }
 225         }
 226
 227         if (!get_recover)
 228                 for_each_ref(mark_complete);
 229
 230         if (interpret_target(target, sha1)) {
 231                 error("Could not interpret %s as something to pull", target);
 232                 if (lock)
 233                         unlock_ref(lock);
 234                 return -1;
 235         }
 236         if (process(lookup_unknown_object(sha1))) {
 237                 if (lock)
 238                         unlock_ref(lock);
 239                 return -1;
 240         }
 241         if (loop()) {
 242                 if (lock)
 243                         unlock_ref(lock);
 244                 return -1;
 245         }
 246
 247         if (write_ref) {
 248                 if (write_ref_log_details) {
 249                         msg = xmalloc(strlen(write_ref_log_details) + 12);
 250                         sprintf(msg, "fetch from %s", write_ref_log_details);
 251                 } else
 252                         msg = NULL;
 253                 ret = write_ref_sha1(lock, sha1, msg ? msg : "fetch (unknown)");
 254                 if (msg)
 255                         free(msg);
 256                 return ret;
 257         }
 258         return 0;
 259 }