reachable.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "tag.h"
   4 #include "commit.h"
   5 #include "blob.h"
   6 #include "diff.h"
   7 #include "revision.h"
   8 #include "reachable.h"
   9 #include "cache-tree.h"
  10 #include "progress.h"
  11 #include "list-objects.h"
  12
  13 struct connectivity_progress {
  14         struct progress *progress;
  15         unsigned long count;
  16 };
  17
  18 static void update_progress(struct connectivity_progress *cp)
  19 {
  20         cp->count++;
  21         if ((cp->count & 1023) == 0)
  22                 display_progress(cp->progress, cp->count);
  23 }
  24
  25 static int add_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
  26 {
  27         struct object *object = parse_object_or_die(sha1, path);
  28         struct rev_info *revs = (struct rev_info *)cb_data;
  29
  30         add_pending_object(revs, object, "");
  31
  32         return 0;
  33 }
  34
  35 static void add_one_tree(const unsigned char *sha1, struct rev_info *revs)
  36 {
  37         struct tree *tree = lookup_tree(sha1);
  38         if (tree)
  39                 add_pending_object(revs, &tree->object, "");
  40 }
  41
  42 static void add_cache_tree(struct cache_tree *it, struct rev_info *revs)
  43 {
  44         int i;
  45
  46         if (it->entry_count >= 0)
  47                 add_one_tree(it->sha1, revs);
  48         for (i = 0; i < it->subtree_nr; i++)
  49                 add_cache_tree(it->down[i]->cache_tree, revs);
  50 }
  51
  52 static void add_cache_refs(struct rev_info *revs)
  53 {
  54         int i;
  55
  56         read_cache();
  57         for (i = 0; i < active_nr; i++) {
  58                 struct blob *blob;
  59
  60                 /*
  61                  * The index can contain blobs and GITLINKs, GITLINKs are hashes
  62                  * that don't actually point to objects in the repository, it's
  63                  * almost guaranteed that they are NOT blobs, so we don't call
  64                  * lookup_blob() on them, to avoid populating the hash table
  65                  * with invalid information
  66                  */
  67                 if (S_ISGITLINK(active_cache[i]->ce_mode))
  68                         continue;
  69
  70                 blob = lookup_blob(active_cache[i]->sha1);
  71                 if (blob)
  72                         blob->object.flags |= SEEN;
  73
  74                 /*
  75                  * We could add the blobs to the pending list, but quite
  76                  * frankly, we don't care. Once we've looked them up, and
  77                  * added them as objects, we've really done everything
  78                  * there is to do for a blob
  79                  */
  80         }
  81         if (active_cache_tree)
  82                 add_cache_tree(active_cache_tree, revs);
  83 }
  84
  85 /*
  86  * The traversal will have already marked us as SEEN, so we
  87  * only need to handle any progress reporting here.
  88  */
  89 static void mark_object(struct object *obj, const struct name_path *path,
  90                         const char *name, void *data)
  91 {
  92         update_progress(data);
  93 }
  94
  95 static void mark_commit(struct commit *c, void *data)
  96 {
  97         mark_object(&c->object, NULL, NULL, data);
  98 }
  99
 100 struct recent_data {
 101         struct rev_info *revs;
 102         unsigned long timestamp;
 103 };
 104
 105 static void add_recent_object(const unsigned char *sha1,
 106                               unsigned long mtime,
 107                               struct recent_data *data)
 108 {
 109         struct object *obj;
 110         enum object_type type;
 111
 112         if (mtime <= data->timestamp)
 113                 return;
 114
 115         /*
 116          * We do not want to call parse_object here, because
 117          * inflating blobs and trees could be very expensive.
 118          * However, we do need to know the correct type for
 119          * later processing, and the revision machinery expects
 120          * commits and tags to have been parsed.
 121          */
 122         type = sha1_object_info(sha1, NULL);
 123         if (type < 0)
 124                 die("unable to get object info for %s", sha1_to_hex(sha1));
 125
 126         switch (type) {
 127         case OBJ_TAG:
 128         case OBJ_COMMIT:
 129                 obj = parse_object_or_die(sha1, NULL);
 130                 break;
 131         case OBJ_TREE:
 132                 obj = (struct object *)lookup_tree(sha1);
 133                 break;
 134         case OBJ_BLOB:
 135                 obj = (struct object *)lookup_blob(sha1);
 136                 break;
 137         default:
 138                 die("unknown object type for %s: %s",
 139                     sha1_to_hex(sha1), typename(type));
 140         }
 141
 142         if (!obj)
 143                 die("unable to lookup %s", sha1_to_hex(sha1));
 144
 145         add_pending_object(data->revs, obj, "");
 146 }
 147
 148 static int add_recent_loose(const unsigned char *sha1,
 149                             const char *path, void *data)
 150 {
 151         struct stat st;
 152         struct object *obj = lookup_object(sha1);
 153
 154         if (obj && obj->flags & SEEN)
 155                 return 0;
 156
 157         if (stat(path, &st) < 0) {
 158                 /*
 159                  * It's OK if an object went away during our iteration; this
 160                  * could be due to a simultaneous repack. But anything else
 161                  * we should abort, since we might then fail to mark objects
 162                  * which should not be pruned.
 163                  */
 164                 if (errno == ENOENT)
 165                         return 0;
 166                 return error("unable to stat %s: %s",
 167                              sha1_to_hex(sha1), strerror(errno));
 168         }
 169
 170         add_recent_object(sha1, st.st_mtime, data);
 171         return 0;
 172 }
 173
 174 static int add_recent_packed(const unsigned char *sha1,
 175                              struct packed_git *p, uint32_t pos,
 176                              void *data)
 177 {
 178         struct object *obj = lookup_object(sha1);
 179
 180         if (obj && obj->flags & SEEN)
 181                 return 0;
 182         add_recent_object(sha1, p->mtime, data);
 183         return 0;
 184 }
 185
 186 int add_unseen_recent_objects_to_traversal(struct rev_info *revs,
 187                                            unsigned long timestamp)
 188 {
 189         struct recent_data data;
 190         int r;
 191
 192         data.revs = revs;
 193         data.timestamp = timestamp;
 194
 195         r = for_each_loose_object(add_recent_loose, &data);
 196         if (r)
 197                 return r;
 198         return for_each_packed_object(add_recent_packed, &data);
 199 }
 200
 201 void mark_reachable_objects(struct rev_info *revs, int mark_reflog,
 202                             unsigned long mark_recent,
 203                             struct progress *progress)
 204 {
 205         struct connectivity_progress cp;
 206
 207         /*
 208          * Set up revision parsing, and mark us as being interested
 209          * in all object types, not just commits.
 210          */
 211         revs->tag_objects = 1;
 212         revs->blob_objects = 1;
 213         revs->tree_objects = 1;
 214
 215         /* Add all refs from the index file */
 216         add_cache_refs(revs);
 217
 218         /* Add all external refs */
 219         for_each_ref(add_one_ref, revs);
 220
 221         /* detached HEAD is not included in the list above */
 222         head_ref(add_one_ref, revs);
 223
 224         /* Add all reflog info */
 225         if (mark_reflog)
 226                 add_reflogs_to_pending(revs, 0);
 227
 228         cp.progress = progress;
 229         cp.count = 0;
 230
 231         /*
 232          * Set up the revision walk - this will move all commits
 233          * from the pending list to the commit walking list.
 234          */
 235         if (prepare_revision_walk(revs))
 236                 die("revision walk setup failed");
 237         traverse_commit_list(revs, mark_commit, mark_object, &cp);
 238
 239         if (mark_recent) {
 240                 revs->ignore_missing_links = 1;
 241                 if (add_unseen_recent_objects_to_traversal(revs, mark_recent))
 242                         die("unable to mark recent objects");
 243                 if (prepare_revision_walk(revs))
 244                         die("revision walk setup failed");
 245                 traverse_commit_list(revs, mark_commit, mark_object, &cp);
 246         }
 247
 248         display_progress(cp.progress, cp.count);
 249 }