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
  11 static void process_blob(struct blob *blob,
  12                          struct object_array *p,
  13                          struct name_path *path,
  14                          const char *name)
  15 {
  16         struct object *obj = &blob->object;
  17
  18         if (!blob)
  19                 die("bad blob object");
  20         if (obj->flags & SEEN)
  21                 return;
  22         obj->flags |= SEEN;
  23         /* Nothing to do, really .. The blob lookup was the important part */
  24 }
  25
  26 static void process_gitlink(const unsigned char *sha1,
  27                             struct object_array *p,
  28                             struct name_path *path,
  29                             const char *name)
  30 {
  31         /* I don't think we want to recurse into this, really. */
  32 }
  33
  34 static void process_tree(struct tree *tree,
  35                          struct object_array *p,
  36                          struct name_path *path,
  37                          const char *name)
  38 {
  39         struct object *obj = &tree->object;
  40         struct tree_desc desc;
  41         struct name_entry entry;
  42         struct name_path me;
  43
  44         if (!tree)
  45                 die("bad tree object");
  46         if (obj->flags & SEEN)
  47                 return;
  48         obj->flags |= SEEN;
  49         if (parse_tree(tree) < 0)
  50                 die("bad tree object %s", sha1_to_hex(obj->sha1));
  51         add_object(obj, p, path, name);
  52         me.up = path;
  53         me.elem = name;
  54         me.elem_len = strlen(name);
  55
  56         init_tree_desc(&desc, tree->buffer, tree->size);
  57
  58         while (tree_entry(&desc, &entry)) {
  59                 if (S_ISDIR(entry.mode))
  60                         process_tree(lookup_tree(entry.sha1), p, &me, entry.path);
  61                 else if (S_ISGITLINK(entry.mode))
  62                         process_gitlink(entry.sha1, p, &me, entry.path);
  63                 else
  64                         process_blob(lookup_blob(entry.sha1), p, &me, entry.path);
  65         }
  66         free(tree->buffer);
  67         tree->buffer = NULL;
  68 }
  69
  70 static void process_tag(struct tag *tag, struct object_array *p, const char *name)
  71 {
  72         struct object *obj = &tag->object;
  73
  74         if (obj->flags & SEEN)
  75                 return;
  76         obj->flags |= SEEN;
  77
  78         if (parse_tag(tag) < 0)
  79                 die("bad tag object %s", sha1_to_hex(obj->sha1));
  80         if (tag->tagged)
  81                 add_object(tag->tagged, p, NULL, name);
  82 }
  83
  84 static void walk_commit_list(struct rev_info *revs)
  85 {
  86         int i;
  87         struct commit *commit;
  88         struct object_array objects = OBJECT_ARRAY_INIT;
  89
  90         /* Walk all commits, process their trees */
  91         while ((commit = get_revision(revs)) != NULL)
  92                 process_tree(commit->tree, &objects, NULL, "");
  93
  94         /* Then walk all the pending objects, recursively processing them too */
  95         for (i = 0; i < revs->pending.nr; i++) {
  96                 struct object_array_entry *pending = revs->pending.objects + i;
  97                 struct object *obj = pending->item;
  98                 const char *name = pending->name;
  99                 if (obj->type == OBJ_TAG) {
 100                         process_tag((struct tag *) obj, &objects, name);
 101                         continue;
 102                 }
 103                 if (obj->type == OBJ_TREE) {
 104                         process_tree((struct tree *)obj, &objects, NULL, name);
 105                         continue;
 106                 }
 107                 if (obj->type == OBJ_BLOB) {
 108                         process_blob((struct blob *)obj, &objects, NULL, name);
 109                         continue;
 110                 }
 111                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 112         }
 113 }
 114
 115 static int add_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 116                 const char *email, unsigned long timestamp, int tz,
 117                 const char *message, void *cb_data)
 118 {
 119         struct object *object;
 120         struct rev_info *revs = (struct rev_info *)cb_data;
 121
 122         object = parse_object(osha1);
 123         if (object)
 124                 add_pending_object(revs, object, "");
 125         object = parse_object(nsha1);
 126         if (object)
 127                 add_pending_object(revs, object, "");
 128         return 0;
 129 }
 130
 131 static int add_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 132 {
 133         struct object *object = parse_object(sha1);
 134         struct rev_info *revs = (struct rev_info *)cb_data;
 135
 136         if (!object)
 137                 die("bad object ref: %s:%s", path, sha1_to_hex(sha1));
 138         add_pending_object(revs, object, "");
 139
 140         return 0;
 141 }
 142
 143 static int add_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 144 {
 145         for_each_reflog_ent(path, add_one_reflog_ent, cb_data);
 146         return 0;
 147 }
 148
 149 static void add_one_tree(const unsigned char *sha1, struct rev_info *revs)
 150 {
 151         struct tree *tree = lookup_tree(sha1);
 152         if (tree)
 153                 add_pending_object(revs, &tree->object, "");
 154 }
 155
 156 static void add_cache_tree(struct cache_tree *it, struct rev_info *revs)
 157 {
 158         int i;
 159
 160         if (it->entry_count >= 0)
 161                 add_one_tree(it->sha1, revs);
 162         for (i = 0; i < it->subtree_nr; i++)
 163                 add_cache_tree(it->down[i]->cache_tree, revs);
 164 }
 165
 166 static void add_cache_refs(struct rev_info *revs)
 167 {
 168         int i;
 169
 170         read_cache();
 171         for (i = 0; i < active_nr; i++) {
 172                 /*
 173                  * The index can contain blobs and GITLINKs, GITLINKs are hashes
 174                  * that don't actually point to objects in the repository, it's
 175                  * almost guaranteed that they are NOT blobs, so we don't call
 176                  * lookup_blob() on them, to avoid populating the hash table
 177                  * with invalid information
 178                  */
 179                 if (S_ISGITLINK(active_cache[i]->ce_mode))
 180                         continue;
 181
 182                 lookup_blob(active_cache[i]->sha1);
 183                 /*
 184                  * We could add the blobs to the pending list, but quite
 185                  * frankly, we don't care. Once we've looked them up, and
 186                  * added them as objects, we've really done everything
 187                  * there is to do for a blob
 188                  */
 189         }
 190         if (active_cache_tree)
 191                 add_cache_tree(active_cache_tree, revs);
 192 }
 193
 194 void mark_reachable_objects(struct rev_info *revs, int mark_reflog)
 195 {
 196         /*
 197          * Set up revision parsing, and mark us as being interested
 198          * in all object types, not just commits.
 199          */
 200         revs->tag_objects = 1;
 201         revs->blob_objects = 1;
 202         revs->tree_objects = 1;
 203
 204         /* Add all refs from the index file */
 205         add_cache_refs(revs);
 206
 207         /* Add all external refs */
 208         for_each_ref(add_one_ref, revs);
 209
 210         /* Add all reflog info */
 211         if (mark_reflog)
 212                 for_each_reflog(add_one_reflog, revs);
 213
 214         /*
 215          * Set up the revision walk - this will move all commits
 216          * from the pending list to the commit walking list.
 217          */
 218         if (prepare_revision_walk(revs))
 219                 die("revision walk setup failed");
 220         walk_commit_list(revs);
 221 }