Code

Merge branch 'lt/dirwalk'
[git.git] / object.c
index 9adc87479bde2a0b2a0a0335aed12a9f485facff..78a44a6ef4e4823487861c9173f3db4a3fb76e3a 100644 (file)
--- a/object.c
+++ b/object.c
 #include "commit.h"
 #include "tag.h"
 
-struct object **objs;
-static int nr_objs;
-int obj_allocs;
+static struct object **obj_hash;
+static int nr_objs, obj_hash_size;
 
-int track_object_refs = 0;
-
-static int hashtable_index(const unsigned char *sha1)
+unsigned int get_max_object_index(void)
 {
-       unsigned int i;
-       memcpy(&i, sha1, sizeof(unsigned int));
-       return (int)(i % obj_allocs);
+       return obj_hash_size;
 }
 
-static int find_object(const unsigned char *sha1)
+struct object *get_indexed_object(unsigned int idx)
 {
-       int i;
-
-       if (!objs)
-               return -1;
-
-       i = hashtable_index(sha1);
-       while (objs[i]) {
-               if (memcmp(sha1, objs[i]->sha1, 20) == 0)
-                       return i;
-               i++;
-               if (i == obj_allocs)
-                       i = 0;
-       }
-       return -1 - i;
+       return obj_hash[idx];
 }
 
-struct object *lookup_object(const unsigned char *sha1)
+static const char *object_type_strings[] = {
+       NULL,           /* OBJ_NONE = 0 */
+       "commit",       /* OBJ_COMMIT = 1 */
+       "tree",         /* OBJ_TREE = 2 */
+       "blob",         /* OBJ_BLOB = 3 */
+       "tag",          /* OBJ_TAG = 4 */
+};
+
+const char *typename(unsigned int type)
 {
-       int pos = find_object(sha1);
-       if (pos >= 0)
-               return objs[pos];
-       return NULL;
+       if (type >= ARRAY_SIZE(object_type_strings))
+               return NULL;
+       return object_type_strings[type];
 }
 
-void created_object(const unsigned char *sha1, struct object *obj)
+int type_from_string(const char *str)
 {
-       int pos;
-
-       obj->parsed = 0;
-       memcpy(obj->sha1, sha1, 20);
-       obj->type = NULL;
-       obj->refs = NULL;
-       obj->used = 0;
-
-       if (obj_allocs - 1 <= nr_objs * 2) {
-               int i, count = obj_allocs;
-               obj_allocs = (obj_allocs < 32 ? 32 : 2 * obj_allocs);
-               objs = xrealloc(objs, obj_allocs * sizeof(struct object *));
-               memset(objs + count, 0, (obj_allocs - count)
-                               * sizeof(struct object *));
-               for (i = 0; i < obj_allocs; i++)
-                       if (objs[i]) {
-                               int j = find_object(objs[i]->sha1);
-                               if (j != i) {
-                                       j = -1 - j;
-                                       objs[j] = objs[i];
-                                       objs[i] = NULL;
-                               }
-                       }
-       }
+       int i;
 
-       pos = find_object(sha1);
-       if (pos >= 0)
-               die("Inserting %s twice\n", sha1_to_hex(sha1));
-       pos = -pos-1;
+       for (i = 1; i < ARRAY_SIZE(object_type_strings); i++)
+               if (!strcmp(str, object_type_strings[i]))
+                       return i;
+       die("invalid object type \"%s\"", str);
+}
 
-       objs[pos] = obj;
-       nr_objs++;
+static unsigned int hash_obj(struct object *obj, unsigned int n)
+{
+       unsigned int hash = *(unsigned int *)obj->sha1;
+       return hash % n;
 }
 
-struct object_refs *alloc_object_refs(unsigned count)
+static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
 {
-       struct object_refs *refs;
-       size_t size = sizeof(*refs) + count*sizeof(struct object *);
+       int j = hash_obj(obj, size);
 
-       refs = xcalloc(1, size);
-       refs->count = count;
-       return refs;
+       while (hash[j]) {
+               j++;
+               if (j >= size)
+                       j = 0;
+       }
+       hash[j] = obj;
 }
 
-static int compare_object_pointers(const void *a, const void *b)
+static int hashtable_index(const unsigned char *sha1)
 {
-       const struct object * const *pa = a;
-       const struct object * const *pb = b;
-       if (*pa == *pb)
-               return 0;
-       else if (*pa < *pb)
-               return -1;
-       else
-               return 1;
+       unsigned int i;
+       memcpy(&i, sha1, sizeof(unsigned int));
+       return (int)(i % obj_hash_size);
 }
 
-void set_object_refs(struct object *obj, struct object_refs *refs)
+struct object *lookup_object(const unsigned char *sha1)
 {
-       unsigned int i, j;
+       int i;
+       struct object *obj;
 
-       /* Do not install empty list of references */
-       if (refs->count < 1) {
-               free(refs);
-               return;
-       }
+       if (!obj_hash)
+               return NULL;
 
-       /* Sort the list and filter out duplicates */
-       qsort(refs->ref, refs->count, sizeof(refs->ref[0]),
-             compare_object_pointers);
-       for (i = j = 1; i < refs->count; i++) {
-               if (refs->ref[i] != refs->ref[i - 1])
-                       refs->ref[j++] = refs->ref[i];
-       }
-       if (j < refs->count) {
-               /* Duplicates were found - reallocate list */
-               size_t size = sizeof(*refs) + j*sizeof(struct object *);
-               refs->count = j;
-               refs = xrealloc(refs, size);
+       i = hashtable_index(sha1);
+       while ((obj = obj_hash[i]) != NULL) {
+               if (!hashcmp(sha1, obj->sha1))
+                       break;
+               i++;
+               if (i == obj_hash_size)
+                       i = 0;
        }
-
-       for (i = 0; i < refs->count; i++)
-               refs->ref[i]->used = 1;
-       obj->refs = refs;
+       return obj;
 }
 
-void mark_reachable(struct object *obj, unsigned int mask)
+static void grow_object_hash(void)
 {
-       if (!track_object_refs)
-               die("cannot do reachability with object refs turned off");
-       /* If we've been here already, don't bother */
-       if (obj->flags & mask)
-               return;
-       obj->flags |= mask;
-       if (obj->refs) {
-               const struct object_refs *refs = obj->refs;
-               unsigned i;
-               for (i = 0; i < refs->count; i++)
-                       mark_reachable(refs->ref[i], mask);
+       int i;
+       int new_hash_size = obj_hash_size < 32 ? 32 : 2 * obj_hash_size;
+       struct object **new_hash;
+
+       new_hash = xcalloc(new_hash_size, sizeof(struct object *));
+       for (i = 0; i < obj_hash_size; i++) {
+               struct object *obj = obj_hash[i];
+               if (!obj)
+                       continue;
+               insert_obj_hash(obj, new_hash, new_hash_size);
        }
+       free(obj_hash);
+       obj_hash = new_hash;
+       obj_hash_size = new_hash_size;
 }
 
-struct object *lookup_object_type(const unsigned char *sha1, const char *type)
+void created_object(const unsigned char *sha1, struct object *obj)
 {
-       if (!type) {
-               return lookup_unknown_object(sha1);
-       } else if (!strcmp(type, blob_type)) {
-               return &lookup_blob(sha1)->object;
-       } else if (!strcmp(type, tree_type)) {
-               return &lookup_tree(sha1)->object;
-       } else if (!strcmp(type, commit_type)) {
-               return &lookup_commit(sha1)->object;
-       } else if (!strcmp(type, tag_type)) {
-               return &lookup_tag(sha1)->object;
-       } else {
-               error("Unknown type %s", type);
-               return NULL;
-       }
+       obj->parsed = 0;
+       obj->used = 0;
+       obj->type = OBJ_NONE;
+       obj->flags = 0;
+       hashcpy(obj->sha1, sha1);
+
+       if (obj_hash_size - 1 <= nr_objs * 2)
+               grow_object_hash();
+
+       insert_obj_hash(obj, obj_hash, obj_hash_size);
+       nr_objs++;
 }
 
 union any_object {
@@ -179,48 +134,64 @@ struct object *lookup_unknown_object(const unsigned char *sha1)
        if (!obj) {
                union any_object *ret = xcalloc(1, sizeof(*ret));
                created_object(sha1, &ret->object);
-               ret->object.type = NULL;
+               ret->object.type = OBJ_NONE;
                return &ret->object;
        }
        return obj;
 }
 
+struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p)
+{
+       struct object *obj;
+       int eaten = 0;
+
+       if (type == OBJ_BLOB) {
+               struct blob *blob = lookup_blob(sha1);
+               parse_blob_buffer(blob, buffer, size);
+               obj = &blob->object;
+       } else if (type == OBJ_TREE) {
+               struct tree *tree = lookup_tree(sha1);
+               obj = &tree->object;
+               if (!tree->object.parsed) {
+                       parse_tree_buffer(tree, buffer, size);
+                       eaten = 1;
+               }
+       } else if (type == OBJ_COMMIT) {
+               struct commit *commit = lookup_commit(sha1);
+               parse_commit_buffer(commit, buffer, size);
+               if (!commit->buffer) {
+                       commit->buffer = buffer;
+                       eaten = 1;
+               }
+               obj = &commit->object;
+       } else if (type == OBJ_TAG) {
+               struct tag *tag = lookup_tag(sha1);
+               parse_tag_buffer(tag, buffer, size);
+               obj = &tag->object;
+       } else {
+               obj = NULL;
+       }
+       *eaten_p = eaten;
+       return obj;
+}
+
 struct object *parse_object(const unsigned char *sha1)
 {
        unsigned long size;
-       char type[20];
-       void *buffer = read_sha1_file(sha1, type, &size);
+       enum object_type type;
+       int eaten;
+       void *buffer = read_sha1_file(sha1, &type, &size);
+
        if (buffer) {
                struct object *obj;
-               if (check_sha1_signature(sha1, buffer, size, type) < 0)
-                       printf("sha1 mismatch %s\n", sha1_to_hex(sha1));
-               if (!strcmp(type, blob_type)) {
-                       struct blob *blob = lookup_blob(sha1);
-                       parse_blob_buffer(blob, buffer, size);
-                       obj = &blob->object;
-               } else if (!strcmp(type, tree_type)) {
-                       struct tree *tree = lookup_tree(sha1);
-                       obj = &tree->object;
-                       if (!tree->object.parsed) {
-                               parse_tree_buffer(tree, buffer, size);
-                               buffer = NULL;
-                       }
-               } else if (!strcmp(type, commit_type)) {
-                       struct commit *commit = lookup_commit(sha1);
-                       parse_commit_buffer(commit, buffer, size);
-                       if (!commit->buffer) {
-                               commit->buffer = buffer;
-                               buffer = NULL;
-                       }
-                       obj = &commit->object;
-               } else if (!strcmp(type, tag_type)) {
-                       struct tag *tag = lookup_tag(sha1);
-                       parse_tag_buffer(tag, buffer, size);
-                       obj = &tag->object;
-               } else {
-                       obj = NULL;
+               if (check_sha1_signature(sha1, buffer, size, typename(type)) < 0) {
+                       error("sha1 mismatch %s\n", sha1_to_hex(sha1));
+                       return NULL;
                }
-               free(buffer);
+
+               obj = parse_object_buffer(sha1, type, size, buffer, &eaten);
+               if (!eaten)
+                       free(buffer);
                return obj;
        }
        return NULL;
@@ -266,3 +237,20 @@ int object_list_contains(struct object_list *list, struct object *obj)
        }
        return 0;
 }
+
+void add_object_array(struct object *obj, const char *name, struct object_array *array)
+{
+       unsigned nr = array->nr;
+       unsigned alloc = array->alloc;
+       struct object_array_entry *objects = array->objects;
+
+       if (nr >= alloc) {
+               alloc = (alloc + 32) * 2;
+               objects = xrealloc(objects, alloc * sizeof(*objects));
+               array->alloc = alloc;
+               array->objects = objects;
+       }
+       objects[nr].item = obj;
+       objects[nr].name = name;
+       array->nr = ++nr;
+}