/object.c
C | 427 lines | 338 code | 49 blank | 40 comment | 90 complexity | 3ed9ee3754bc580c4ec08de7ff5b2657 MD5 | raw file
- #include "cache.h"
- #include "object.h"
- #include "blob.h"
- #include "tree.h"
- #include "commit.h"
- #include "tag.h"
- static struct object **obj_hash;
- static int nr_objs, obj_hash_size;
- unsigned int get_max_object_index(void)
- {
- return obj_hash_size;
- }
- struct object *get_indexed_object(unsigned int idx)
- {
- return obj_hash[idx];
- }
- 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)
- {
- if (type >= ARRAY_SIZE(object_type_strings))
- return NULL;
- return object_type_strings[type];
- }
- int type_from_string_gently(const char *str, ssize_t len, int gentle)
- {
- int i;
- if (len < 0)
- len = strlen(str);
- for (i = 1; i < ARRAY_SIZE(object_type_strings); i++)
- if (!strncmp(str, object_type_strings[i], len) &&
- object_type_strings[i][len] == '\0')
- return i;
- if (gentle)
- return -1;
- die("invalid object type \"%s\"", str);
- }
- /*
- * Return a numerical hash value between 0 and n-1 for the object with
- * the specified sha1. n must be a power of 2. Please note that the
- * return value is *not* consistent across computer architectures.
- */
- static unsigned int hash_obj(const unsigned char *sha1, unsigned int n)
- {
- return sha1hash(sha1) & (n - 1);
- }
- /*
- * Insert obj into the hash table hash, which has length size (which
- * must be a power of 2). On collisions, simply overflow to the next
- * empty bucket.
- */
- static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
- {
- unsigned int j = hash_obj(obj->oid.hash, size);
- while (hash[j]) {
- j++;
- if (j >= size)
- j = 0;
- }
- hash[j] = obj;
- }
- /*
- * Look up the record for the given sha1 in the hash map stored in
- * obj_hash. Return NULL if it was not found.
- */
- struct object *lookup_object(const unsigned char *sha1)
- {
- unsigned int i, first;
- struct object *obj;
- if (!obj_hash)
- return NULL;
- first = i = hash_obj(sha1, obj_hash_size);
- while ((obj = obj_hash[i]) != NULL) {
- if (!hashcmp(sha1, obj->oid.hash))
- break;
- i++;
- if (i == obj_hash_size)
- i = 0;
- }
- if (obj && i != first) {
- /*
- * Move object to where we started to look for it so
- * that we do not need to walk the hash table the next
- * time we look for it.
- */
- struct object *tmp = obj_hash[i];
- obj_hash[i] = obj_hash[first];
- obj_hash[first] = tmp;
- }
- return obj;
- }
- /*
- * Increase the size of the hash map stored in obj_hash to the next
- * power of 2 (but at least 32). Copy the existing values to the new
- * hash map.
- */
- static void grow_object_hash(void)
- {
- int i;
- /*
- * Note that this size must always be power-of-2 to match hash_obj
- * above.
- */
- 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;
- }
- void *create_object(const unsigned char *sha1, void *o)
- {
- struct object *obj = o;
- obj->parsed = 0;
- obj->used = 0;
- obj->flags = 0;
- hashcpy(obj->oid.hash, sha1);
- if (obj_hash_size - 1 <= nr_objs * 2)
- grow_object_hash();
- insert_obj_hash(obj, obj_hash, obj_hash_size);
- nr_objs++;
- return obj;
- }
- void *object_as_type(struct object *obj, enum object_type type, int quiet)
- {
- if (obj->type == type)
- return obj;
- else if (obj->type == OBJ_NONE) {
- if (type == OBJ_COMMIT)
- ((struct commit *)obj)->index = alloc_commit_index();
- obj->type = type;
- return obj;
- }
- else {
- if (!quiet)
- error("object %s is a %s, not a %s",
- oid_to_hex(&obj->oid),
- typename(obj->type), typename(type));
- return NULL;
- }
- }
- struct object *lookup_unknown_object(const unsigned char *sha1)
- {
- struct object *obj = lookup_object(sha1);
- if (!obj)
- obj = create_object(sha1, alloc_object_node());
- 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;
- *eaten_p = 0;
- obj = NULL;
- if (type == OBJ_BLOB) {
- struct blob *blob = lookup_blob(sha1);
- if (blob) {
- if (parse_blob_buffer(blob, buffer, size))
- return NULL;
- obj = &blob->object;
- }
- } else if (type == OBJ_TREE) {
- struct tree *tree = lookup_tree(sha1);
- if (tree) {
- obj = &tree->object;
- if (!tree->buffer)
- tree->object.parsed = 0;
- if (!tree->object.parsed) {
- if (parse_tree_buffer(tree, buffer, size))
- return NULL;
- *eaten_p = 1;
- }
- }
- } else if (type == OBJ_COMMIT) {
- struct commit *commit = lookup_commit(sha1);
- if (commit) {
- if (parse_commit_buffer(commit, buffer, size))
- return NULL;
- if (!get_cached_commit_buffer(commit, NULL)) {
- set_commit_buffer(commit, buffer, size);
- *eaten_p = 1;
- }
- obj = &commit->object;
- }
- } else if (type == OBJ_TAG) {
- struct tag *tag = lookup_tag(sha1);
- if (tag) {
- if (parse_tag_buffer(tag, buffer, size))
- return NULL;
- obj = &tag->object;
- }
- } else {
- warning("object %s has unknown type id %d", sha1_to_hex(sha1), type);
- obj = NULL;
- }
- return obj;
- }
- struct object *parse_object_or_die(const unsigned char *sha1,
- const char *name)
- {
- struct object *o = parse_object(sha1);
- if (o)
- return o;
- die(_("unable to parse object: %s"), name ? name : sha1_to_hex(sha1));
- }
- struct object *parse_object(const unsigned char *sha1)
- {
- unsigned long size;
- enum object_type type;
- int eaten;
- const unsigned char *repl = lookup_replace_object(sha1);
- void *buffer;
- struct object *obj;
- obj = lookup_object(sha1);
- if (obj && obj->parsed)
- return obj;
- if ((obj && obj->type == OBJ_BLOB) ||
- (!obj && has_sha1_file(sha1) &&
- sha1_object_info(sha1, NULL) == OBJ_BLOB)) {
- if (check_sha1_signature(repl, NULL, 0, NULL) < 0) {
- error("sha1 mismatch %s", sha1_to_hex(repl));
- return NULL;
- }
- parse_blob_buffer(lookup_blob(sha1), NULL, 0);
- return lookup_object(sha1);
- }
- buffer = read_sha1_file(sha1, &type, &size);
- if (buffer) {
- if (check_sha1_signature(repl, buffer, size, typename(type)) < 0) {
- free(buffer);
- error("sha1 mismatch %s", sha1_to_hex(repl));
- return NULL;
- }
- obj = parse_object_buffer(sha1, type, size, buffer, &eaten);
- if (!eaten)
- free(buffer);
- return obj;
- }
- return NULL;
- }
- struct object_list *object_list_insert(struct object *item,
- struct object_list **list_p)
- {
- struct object_list *new_list = xmalloc(sizeof(struct object_list));
- new_list->item = item;
- new_list->next = *list_p;
- *list_p = new_list;
- return new_list;
- }
- int object_list_contains(struct object_list *list, struct object *obj)
- {
- while (list) {
- if (list->item == obj)
- return 1;
- list = list->next;
- }
- return 0;
- }
- /*
- * A zero-length string to which object_array_entry::name can be
- * initialized without requiring a malloc/free.
- */
- static char object_array_slopbuf[1];
- void add_object_array_with_path(struct object *obj, const char *name,
- struct object_array *array,
- unsigned mode, const char *path)
- {
- unsigned nr = array->nr;
- unsigned alloc = array->alloc;
- struct object_array_entry *objects = array->objects;
- struct object_array_entry *entry;
- if (nr >= alloc) {
- alloc = (alloc + 32) * 2;
- REALLOC_ARRAY(objects, alloc);
- array->alloc = alloc;
- array->objects = objects;
- }
- entry = &objects[nr];
- entry->item = obj;
- if (!name)
- entry->name = NULL;
- else if (!*name)
- /* Use our own empty string instead of allocating one: */
- entry->name = object_array_slopbuf;
- else
- entry->name = xstrdup(name);
- entry->mode = mode;
- if (path)
- entry->path = xstrdup(path);
- else
- entry->path = NULL;
- array->nr = ++nr;
- }
- void add_object_array(struct object *obj, const char *name, struct object_array *array)
- {
- add_object_array_with_path(obj, name, array, S_IFINVALID, NULL);
- }
- /*
- * Free all memory associated with an entry; the result is
- * in an unspecified state and should not be examined.
- */
- static void object_array_release_entry(struct object_array_entry *ent)
- {
- if (ent->name != object_array_slopbuf)
- free(ent->name);
- free(ent->path);
- }
- void object_array_filter(struct object_array *array,
- object_array_each_func_t want, void *cb_data)
- {
- unsigned nr = array->nr, src, dst;
- struct object_array_entry *objects = array->objects;
- for (src = dst = 0; src < nr; src++) {
- if (want(&objects[src], cb_data)) {
- if (src != dst)
- objects[dst] = objects[src];
- dst++;
- } else {
- object_array_release_entry(&objects[src]);
- }
- }
- array->nr = dst;
- }
- void object_array_clear(struct object_array *array)
- {
- int i;
- for (i = 0; i < array->nr; i++)
- object_array_release_entry(&array->objects[i]);
- free(array->objects);
- array->objects = NULL;
- array->nr = array->alloc = 0;
- }
- /*
- * Return true iff array already contains an entry with name.
- */
- static int contains_name(struct object_array *array, const char *name)
- {
- unsigned nr = array->nr, i;
- struct object_array_entry *object = array->objects;
- for (i = 0; i < nr; i++, object++)
- if (!strcmp(object->name, name))
- return 1;
- return 0;
- }
- void object_array_remove_duplicates(struct object_array *array)
- {
- unsigned nr = array->nr, src;
- struct object_array_entry *objects = array->objects;
- array->nr = 0;
- for (src = 0; src < nr; src++) {
- if (!contains_name(array, objects[src].name)) {
- if (src != array->nr)
- objects[array->nr] = objects[src];
- array->nr++;
- } else {
- object_array_release_entry(&objects[src]);
- }
- }
- }
- void clear_object_flags(unsigned flags)
- {
- int i;
- for (i=0; i < obj_hash_size; i++) {
- struct object *obj = obj_hash[i];
- if (obj)
- obj->flags &= ~flags;
- }
- }