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 (obj->flags & SEEN)
  19                 return;
  20         obj->flags |= SEEN;
  21         /* Nothing to do, really .. The blob lookup was the important part */
  22 }
  23
  24 static void process_gitlink(const unsigned char *sha1,
  25                             struct object_array *p,
  26                             struct name_path *path,
  27                             const char *name)
  28 {
  29         /* I don't think we want to recurse into this, really. */
  30 }
  31
  32 static void process_tree(struct tree *tree,
  33                          struct object_array *p,
  34                          struct name_path *path,
  35                          const char *name)
  36 {
  37         struct object *obj = &tree->object;
  38         struct tree_desc desc;
  39         struct name_entry entry;
  40         struct name_path me;
  41
  42         if (obj->flags & SEEN)
  43                 return;
  44         obj->flags |= SEEN;
  45         if (parse_tree(tree) < 0)
  46                 die("bad tree object %s", sha1_to_hex(obj->sha1));
  47         name = xstrdup(name);
  48         add_object(obj, p, path, name);
  49         me.up = path;
  50         me.elem = name;
  51         me.elem_len = strlen(name);
  52
  53         init_tree_desc(&desc, tree->buffer, tree->size);
  54
  55         while (tree_entry(&desc, &entry)) {
  56                 if (S_ISDIR(entry.mode))
  57                         process_tree(lookup_tree(entry.sha1), p, &me, entry.path);
  58                 else if (S_ISGITLINK(entry.mode))
  59                         process_gitlink(entry.sha1, p, &me, entry.path);
  60                 else
  61                         process_blob(lookup_blob(entry.sha1), p, &me, entry.path);
  62         }
  63         free(tree->buffer);
  64         tree->buffer = NULL;
  65 }
  66
  67 static void process_tag(struct tag *tag, struct object_array *p, const char *name)
  68 {
  69         struct object *obj = &tag->object;
  70         struct name_path me;
  71
  72         if (obj->flags & SEEN)
  73                 return;
  74         obj->flags |= SEEN;
  75
  76         me.up = NULL;
  77         me.elem = "tag:/";
  78         me.elem_len = 5;
  79
  80         if (parse_tag(tag) < 0)
  81                 die("bad tag object %s", sha1_to_hex(obj->sha1));
  82         add_object(tag->tagged, p, NULL, name);
  83 }
  84
  85 static void walk_commit_list(struct rev_info *revs)
  86 {
  87         int i;
  88         struct commit *commit;
  89         struct object_array objects = { 0, 0, NULL };
  90
  91         /* Walk all commits, process their trees */
  92         while ((commit = get_revision(revs)) != NULL)
  93                 process_tree(commit->tree, &objects, NULL, "");
  94
  95         /* Then walk all the pending objects, recursively processing them too */
  96         for (i = 0; i < revs->pending.nr; i++) {
  97                 struct object_array_entry *pending = revs->pending.objects + i;
  98                 struct object *obj = pending->item;
  99                 const char *name = pending->name;
 100                 if (obj->type == OBJ_TAG) {
 101                         process_tag((struct tag *) obj, &objects, name);
 102                         continue;
 103                 }
 104                 if (obj->type == OBJ_TREE) {
 105                         process_tree((struct tree *)obj, &objects, NULL, name);
 106                         continue;
 107                 }
 108                 if (obj->type == OBJ_BLOB) {
 109                         process_blob((struct blob *)obj, &objects, NULL, name);
 110                         continue;
 111                 }
 112                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 113         }
 114 }
 115
 116 static int add_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 117                 const char *email, unsigned long timestamp, int tz,
 118                 const char *message, void *cb_data)
 119 {
 120         struct object *object;
 121         struct rev_info *revs = (struct rev_info *)cb_data;
 122
 123         object = parse_object(osha1);
 124         if (object)
 125                 add_pending_object(revs, object, "");
 126         object = parse_object(nsha1);
 127         if (object)
 128                 add_pending_object(revs, object, "");
 129         return 0;
 130 }
 131
 132 static int add_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 133 {
 134         struct object *object = parse_object(sha1);
 135         struct rev_info *revs = (struct rev_info *)cb_data;
 136
 137         if (!object)
 138                 die("bad object ref: %s:%s", path, sha1_to_hex(sha1));
 139         add_pending_object(revs, object, "");
 140
 141         return 0;
 142 }
 143
 144 static int add_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 145 {
 146         for_each_reflog_ent(path, add_one_reflog_ent, cb_data);
 147         return 0;
 148 }
 149
 150 static void add_one_tree(const unsigned char *sha1, struct rev_info *revs)
 151 {
 152         struct tree *tree = lookup_tree(sha1);
 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(ntohl(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         prepare_revision_walk(revs);
 219         walk_commit_list(revs);
 220 }