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_tree(struct tree *tree,
  25                          struct object_array *p,
  26                          struct name_path *path,
  27                          const char *name)
  28 {
  29         struct object *obj = &tree->object;
  30         struct tree_desc desc;
  31         struct name_entry entry;
  32         struct name_path me;
  33
  34         if (obj->flags & SEEN)
  35                 return;
  36         obj->flags |= SEEN;
  37         if (parse_tree(tree) < 0)
  38                 die("bad tree object %s", sha1_to_hex(obj->sha1));
  39         name = xstrdup(name);
  40         add_object(obj, p, path, name);
  41         me.up = path;
  42         me.elem = name;
  43         me.elem_len = strlen(name);
  44
  45         desc.buf = tree->buffer;
  46         desc.size = tree->size;
  47
  48         while (tree_entry(&desc, &entry)) {
  49                 if (S_ISDIR(entry.mode))
  50                         process_tree(lookup_tree(entry.sha1), p, &me, entry.path);
  51                 else
  52                         process_blob(lookup_blob(entry.sha1), p, &me, entry.path);
  53         }
  54         free(tree->buffer);
  55         tree->buffer = NULL;
  56 }
  57
  58 static void process_tag(struct tag *tag, struct object_array *p, const char *name)
  59 {
  60         struct object *obj = &tag->object;
  61         struct name_path me;
  62
  63         if (obj->flags & SEEN)
  64                 return;
  65         obj->flags |= SEEN;
  66
  67         me.up = NULL;
  68         me.elem = "tag:/";
  69         me.elem_len = 5;
  70
  71         if (parse_tag(tag) < 0)
  72                 die("bad tag object %s", sha1_to_hex(obj->sha1));
  73         add_object(tag->tagged, p, NULL, name);
  74 }
  75
  76 static void walk_commit_list(struct rev_info *revs)
  77 {
  78         int i;
  79         struct commit *commit;
  80         struct object_array objects = { 0, 0, NULL };
  81
  82         /* Walk all commits, process their trees */
  83         while ((commit = get_revision(revs)) != NULL)
  84                 process_tree(commit->tree, &objects, NULL, "");
  85
  86         /* Then walk all the pending objects, recursively processing them too */
  87         for (i = 0; i < revs->pending.nr; i++) {
  88                 struct object_array_entry *pending = revs->pending.objects + i;
  89                 struct object *obj = pending->item;
  90                 const char *name = pending->name;
  91                 if (obj->type == OBJ_TAG) {
  92                         process_tag((struct tag *) obj, &objects, name);
  93                         continue;
  94                 }
  95                 if (obj->type == OBJ_TREE) {
  96                         process_tree((struct tree *)obj, &objects, NULL, name);
  97                         continue;
  98                 }
  99                 if (obj->type == OBJ_BLOB) {
 100                         process_blob((struct blob *)obj, &objects, NULL, name);
 101                         continue;
 102                 }
 103                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
 104         }
 105 }
 106
 107 static int add_one_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 108                 const char *email, unsigned long timestamp, int tz,
 109                 const char *message, void *cb_data)
 110 {
 111         struct object *object;
 112         struct rev_info *revs = (struct rev_info *)cb_data;
 113
 114         object = parse_object(osha1);
 115         if (object)
 116                 add_pending_object(revs, object, "");
 117         object = parse_object(nsha1);
 118         if (object)
 119                 add_pending_object(revs, object, "");
 120         return 0;
 121 }
 122
 123 static int add_one_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 124 {
 125         struct object *object = parse_object(sha1);
 126         struct rev_info *revs = (struct rev_info *)cb_data;
 127
 128         if (!object)
 129                 die("bad object ref: %s:%s", path, sha1_to_hex(sha1));
 130         add_pending_object(revs, object, "");
 131
 132         return 0;
 133 }
 134
 135 static int add_one_reflog(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 136 {
 137         for_each_reflog_ent(path, add_one_reflog_ent, cb_data);
 138         return 0;
 139 }
 140
 141 static void add_one_tree(const unsigned char *sha1, struct rev_info *revs)
 142 {
 143         struct tree *tree = lookup_tree(sha1);
 144         add_pending_object(revs, &tree->object, "");
 145 }
 146
 147 static void add_cache_tree(struct cache_tree *it, struct rev_info *revs)
 148 {
 149         int i;
 150
 151         if (it->entry_count >= 0)
 152                 add_one_tree(it->sha1, revs);
 153         for (i = 0; i < it->subtree_nr; i++)
 154                 add_cache_tree(it->down[i]->cache_tree, revs);
 155 }
 156
 157 static void add_cache_refs(struct rev_info *revs)
 158 {
 159         int i;
 160
 161         read_cache();
 162         for (i = 0; i < active_nr; i++) {
 163                 lookup_blob(active_cache[i]->sha1);
 164                 /*
 165                  * We could add the blobs to the pending list, but quite
 166                  * frankly, we don't care. Once we've looked them up, and
 167                  * added them as objects, we've really done everything
 168                  * there is to do for a blob
 169                  */
 170         }
 171         if (active_cache_tree)
 172                 add_cache_tree(active_cache_tree, revs);
 173 }
 174
 175 void mark_reachable_objects(struct rev_info *revs, int mark_reflog)
 176 {
 177         /*
 178          * Set up revision parsing, and mark us as being interested
 179          * in all object types, not just commits.
 180          */
 181         revs->tag_objects = 1;
 182         revs->blob_objects = 1;
 183         revs->tree_objects = 1;
 184
 185         /* Add all refs from the index file */
 186         add_cache_refs(revs);
 187
 188         /* Add all external refs */
 189         for_each_ref(add_one_ref, revs);
 190
 191         /* Add all reflog info */
 192         if (mark_reflog)
 193                 for_each_reflog(add_one_reflog, revs);
 194
 195         /*
 196          * Set up the revision walk - this will move all commits
 197          * from the pending list to the commit walking list.
 198          */
 199         prepare_revision_walk(revs);
 200         walk_commit_list(revs);
 201 }