git-svnimport: support for incremental import
[gitweb.git] / object.c
index 1fdebe012ba8a6db0b6eae443e40a7f74ae2d597..de244e206375d43f2bd327a0c3058ea24d53704e 100644 (file)
--- a/object.c
+++ b/object.c
+#include "cache.h"
 #include "object.h"
 #include "blob.h"
 #include "tree.h"
 #include "commit.h"
-#include "cache.h"
 #include "tag.h"
 
-struct object **objs;
-int nr_objs;
-static int obj_allocs;
+static struct object **obj_hash;
+static int nr_objs, obj_hash_size;
 
-int track_object_refs = 1;
-
-static int find_object(const unsigned char *sha1)
+unsigned int get_max_object_index(void)
 {
-       int first = 0, last = nr_objs;
-
-        while (first < last) {
-                int next = (first + last) / 2;
-                struct object *obj = objs[next];
-                int cmp;
-
-                cmp = memcmp(sha1, obj->sha1, 20);
-                if (!cmp)
-                        return next;
-                if (cmp < 0) {
-                        last = next;
-                        continue;
-                }
-                first = next+1;
-        }
-        return -first-1;
+       return obj_hash_size;
 }
 
-struct object *lookup_object(const unsigned char *sha1)
+struct object *get_indexed_object(unsigned int idx)
 {
-       int pos = find_object(sha1);
-       if (pos >= 0)
-               return objs[pos];
-       return NULL;
+       return obj_hash[idx];
 }
 
-void created_object(const unsigned char *sha1, struct object *obj)
-{
-       int pos = find_object(sha1);
+const char *type_names[] = {
+       "none", "commit", "tree", "blob", "tag",
+       "bad type 5", "bad type 6", "delta", "bad",
+};
 
-       obj->parsed = 0;
-       memcpy(obj->sha1, sha1, 20);
-       obj->type = NULL;
-       obj->refs = NULL;
-       obj->used = 0;
+static unsigned int hash_obj(struct object *obj, unsigned int n)
+{
+       unsigned int hash = *(unsigned int *)obj->sha1;
+       return hash % n;
+}
 
-       if (pos >= 0)
-               die("Inserting %s twice\n", sha1_to_hex(sha1));
-       pos = -pos-1;
+static void insert_obj_hash(struct object *obj, struct object **hash, unsigned int size)
+{
+       int j = hash_obj(obj, size);
 
-       if (obj_allocs == nr_objs) {
-               obj_allocs = alloc_nr(obj_allocs);
-               objs = xrealloc(objs, obj_allocs * sizeof(struct object *));
+       while (hash[j]) {
+               j++;
+               if (j >= size)
+                       j = 0;
        }
+       hash[j] = obj;
+}
 
-       /* Insert it into the right place */
-       memmove(objs + pos + 1, objs + pos, (nr_objs - pos) * 
-               sizeof(struct object *));
-
-       objs[pos] = obj;
-       nr_objs++;
+static int hashtable_index(const unsigned char *sha1)
+{
+       unsigned int i;
+       memcpy(&i, sha1, sizeof(unsigned int));
+       return (int)(i % obj_hash_size);
 }
 
-void add_ref(struct object *refer, struct object *target)
+struct object *lookup_object(const unsigned char *sha1)
 {
-       struct object_list **pp, *p;
+       int i;
+       struct object *obj;
 
-       if (!track_object_refs)
-               return;
+       if (!obj_hash)
+               return NULL;
 
-       pp = &refer->refs;
-       while ((p = *pp) != NULL) {
-               if (p->item == target)
-                       return;
-               pp = &p->next;
+       i = hashtable_index(sha1);
+       while ((obj = obj_hash[i]) != NULL) {
+               if (!hashcmp(sha1, obj->sha1))
+                       break;
+               i++;
+               if (i == obj_hash_size)
+                       i = 0;
        }
+       return obj;
+}
 
-       target->used = 1;
-       p = xmalloc(sizeof(*p));
-       p->item = target;
-       p->next = NULL;
-       *pp = p;
+static void grow_object_hash(void)
+{
+       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;
 }
 
-void mark_reachable(struct object *obj, unsigned int mask)
+void created_object(const unsigned char *sha1, struct object *obj)
 {
-       struct object_list *p = obj->refs;
+       obj->parsed = 0;
+       obj->used = 0;
+       obj->type = OBJ_NONE;
+       obj->flags = 0;
+       hashcpy(obj->sha1, sha1);
 
-       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;
-       while (p) {
-               mark_reachable(p->item, mask);
-               p = p->next;
-       }
+       if (obj_hash_size - 1 <= nr_objs * 2)
+               grow_object_hash();
+
+       insert_obj_hash(obj, obj_hash, obj_hash_size);
+       nr_objs++;
 }
 
 struct object *lookup_object_type(const unsigned char *sha1, const char *type)
@@ -134,48 +130,64 @@ struct object *lookup_unknown_object(const unsigned char *sha1)
 {
        struct object *obj = lookup_object(sha1);
        if (!obj) {
-               union any_object *ret = xmalloc(sizeof(*ret));
-               memset(ret, 0, sizeof(*ret));
+               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, const char *type, unsigned long size, void *buffer, int *eaten_p)
+{
+       struct object *obj;
+       int eaten = 0;
+
+       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);
+                       eaten = 1;
+               }
+       } else if (!strcmp(type, commit_type)) {
+               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 (!strcmp(type, tag_type)) {
+               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];
+       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")) {
-                       struct blob *blob = lookup_blob(sha1);
-                       parse_blob_buffer(blob, buffer, size);
-                       obj = &blob->object;
-               } else if (!strcmp(type, "tree")) {
-                       struct tree *tree = lookup_tree(sha1);
-                       parse_tree_buffer(tree, buffer, size);
-                       obj = &tree->object;
-               } else if (!strcmp(type, "commit")) {
-                       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")) {
-                       struct tag *tag = lookup_tag(sha1);
-                       parse_tag_buffer(tag, buffer, size);
-                       obj = &tag->object;
-               } else {
-                       obj = NULL;
-               }
-               free(buffer);
+
+               obj = parse_object_buffer(sha1, type, size, buffer, &eaten);
+               if (!eaten)
+                       free(buffer);
                return obj;
        }
        return NULL;
@@ -221,3 +233,20 @@ 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;
+}