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         name = xstrdup(name);
  52         add_object(obj, p, path, name);
  53         me.up = path;
  54         me.elem = name;
  55         me.elem_len = strlen(name);
  56
  57         init_tree_desc(&desc, tree->buffer, tree->size);
  58
  59         while (tree_entry(&desc, &entry)) {
  60                 if (S_ISDIR(entry.mode))
  61                         process_tree(lookup_tree(entry.sha1), p, &me, entry.path);
  62                 else if (S_ISGITLINK(entry.mode))
  63                         process_gitlink(entry.sha1, p, &me, entry.path);
  64                 else
  65                         process_blob(lookup_blob(entry.sha1), p, &me, entry.path);
  66         }
  67         free(tree->buffer);
  68         tree->buffer = NULL;
  69 }
  70
  71 static void process_tag(struct tag *tag, struct object_array *p, const char *name)
  72 {
  73         struct object *obj = &tag->object;
  74         struct name_path me;
  75
  76         if (obj->flags & SEEN)
  77                 return;
  78         obj->flags |= SEEN;
  79
  80         me.up = NULL;
  81         me.elem = "tag:/";
  82         me.elem_len = 5;
  83
  84         if (parse_tag(tag) < 0)
  85                 die("bad tag object %s", sha1_to_hex(obj->sha1));
  86         if (tag->tagged)
  87                 add_object(tag->tagged, p, NULL, name);
  88 }
  89
  90 static void walk_commit_list(struct rev_info *revs)
  91 {
  92         int i;
  93         struct commit *commit;
  94         struct object_array objects = { 0, 0, NULL };
  95
  96         /* Walk all commits, process their trees */
  97         while ((commit = get_revision(revs)) != NULL)
  98                 process_tree(commit->tree, &objects, NULL, "");
  99
 100         /* Then walk all the pending objects, recursively processing them too */
 101         for (i = 0; i < revs->pending.nr; i++) {
 102                 struct object_array_entry *pending = revs->pending.objects + i;
 103                 struct object *obj = pending->item;
 104                 const char *name = pending->name;
 105                 if (obj->type == OBJ_TAG) {
 106                         process_tag((struct tag *) obj, &objects, name);
 107                         continue;
 108                 }
 109                 if (obj->type == OBJ_TREE) {
 110                         process_tree((struct tree *)obj, &objects, NULL, name);
 111                         continue;
 112                 }
 113                 if (obj->type == OBJ_BLOB) {
 114                         process_blob((struct blob *)obj, &objects, NULL, name);
 115                         continue;
 116                 }
 117                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 118         }
 119 }
 120
 121 static int add_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 122                 const char *email, unsigned long timestamp, int tz,
 123                 const char *message, void *cb_data)
 124 {
 125         struct object *object;
 126         struct rev_info *revs = (struct rev_info *)cb_data;
 127
 128         object = parse_object(osha1);
 129         if (object)
 130                 add_pending_object(revs, object, "");
 131         object = parse_object(nsha1);
 132         if (object)
 133                 add_pending_object(revs, object, "");
 134         return 0;
 135 }
 136
 137 static int add_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 138 {
 139         struct object *object = parse_object(sha1);
 140         struct rev_info *revs = (struct rev_info *)cb_data;
 141
 142         if (!object)
 143                 die("bad object ref: %s:%s", path, sha1_to_hex(sha1));
 144         add_pending_object(revs, object, "");
 145
 146         return 0;
 147 }
 148
 149 static int add_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 150 {
 151         for_each_reflog_ent(path, add_one_reflog_ent, cb_data);
 152         return 0;
 153 }
 154
 155 static void add_one_tree(const unsigned char *sha1, struct rev_info *revs)
 156 {
 157         struct tree *tree = lookup_tree(sha1);
 158         if (tree)
 159                 add_pending_object(revs, &tree->object, "");
 160 }
 161
 162 static void add_cache_tree(struct cache_tree *it, struct rev_info *revs)
 163 {
 164         int i;
 165
 166         if (it->entry_count >= 0)
 167                 add_one_tree(it->sha1, revs);
 168         for (i = 0; i < it->subtree_nr; i++)
 169                 add_cache_tree(it->down[i]->cache_tree, revs);
 170 }
 171
 172 static void add_cache_refs(struct rev_info *revs)
 173 {
 174         int i;
 175
 176         read_cache();
 177         for (i = 0; i < active_nr; i++) {
 178                 /*
 179                  * The index can contain blobs and GITLINKs, GITLINKs are hashes
 180                  * that don't actually point to objects in the repository, it's
 181                  * almost guaranteed that they are NOT blobs, so we don't call
 182                  * lookup_blob() on them, to avoid populating the hash table
 183                  * with invalid information
 184                  */
 185                 if (S_ISGITLINK(active_cache[i]->ce_mode))
 186                         continue;
 187
 188                 lookup_blob(active_cache[i]->sha1);
 189                 /*
 190                  * We could add the blobs to the pending list, but quite
 191                  * frankly, we don't care. Once we've looked them up, and
 192                  * added them as objects, we've really done everything
 193                  * there is to do for a blob
 194                  */
 195         }
 196         if (active_cache_tree)
 197                 add_cache_tree(active_cache_tree, revs);
 198 }
 199
 200 void mark_reachable_objects(struct rev_info *revs, int mark_reflog)
 201 {
 202         /*
 203          * Set up revision parsing, and mark us as being interested
 204          * in all object types, not just commits.
 205          */
 206         revs->tag_objects = 1;
 207         revs->blob_objects = 1;
 208         revs->tree_objects = 1;
 209
 210         /* Add all refs from the index file */
 211         add_cache_refs(revs);
 212
 213         /* Add all external refs */
 214         for_each_ref(add_one_ref, revs);
 215
 216         /* Add all reflog info */
 217         if (mark_reflog)
 218                 for_each_reflog(add_one_reflog, revs);
 219
 220         /*
 221          * Set up the revision walk - this will move all commits
 222          * from the pending list to the commit walking list.
 223          */
 224         if (prepare_revision_walk(revs))
 225                 die("revision walk setup failed");
 226         walk_commit_list(revs);
 227 }