From f41aebd46998c8b6df3733196d55aeb7162b3df6 Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Sun, 13 Jul 2008 22:07:44 -0400 Subject: [PATCH] index-pack: Refactor base arguments of resolve_delta into a struct We need to discard base objects which are not recently used if our memory gets low, such as when we are unpacking a long delta chain of a very large object. To support tracking the available base objects we combine the pointer and size into a struct. Future changes would allow the data pointer to be free'd and marked NULL if memory gets low. Signed-off-by: Shawn O. Pearce Signed-off-by: Junio C Hamano --- index-pack.c | 60 +++++++++++++++++++++++++++++----------------------- 1 file changed, 33 insertions(+), 27 deletions(-) diff --git a/index-pack.c b/index-pack.c index 5ac91baf9..8162265a6 100644 --- a/index-pack.c +++ b/index-pack.c @@ -26,6 +26,11 @@ union delta_base { off_t offset; }; +struct base_data { + void *data; + unsigned long size; +}; + /* * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want * to memcmp() only the first 20 bytes. @@ -425,25 +430,25 @@ static void sha1_object(const void *data, unsigned long size, } } -static void resolve_delta(struct object_entry *delta_obj, void *base_data, - unsigned long base_size, enum object_type type) +static void resolve_delta(struct object_entry *delta_obj, + struct base_data *base_obj, enum object_type type) { void *delta_data; unsigned long delta_size; - void *result; - unsigned long result_size; union delta_base delta_base; int j, first, last; + struct base_data result; delta_obj->real_type = type; delta_data = get_data_from_pack(delta_obj); delta_size = delta_obj->size; - result = patch_delta(base_data, base_size, delta_data, delta_size, - &result_size); + result.data = patch_delta(base_obj->data, base_obj->size, + delta_data, delta_size, + &result.size); free(delta_data); - if (!result) + if (!result.data) bad_object(delta_obj->idx.offset, "failed to apply delta"); - sha1_object(result, result_size, type, delta_obj->idx.sha1); + sha1_object(result.data, result.size, type, delta_obj->idx.sha1); nr_resolved_deltas++; hashcpy(delta_base.sha1, delta_obj->idx.sha1); @@ -451,7 +456,7 @@ static void resolve_delta(struct object_entry *delta_obj, void *base_data, for (j = first; j <= last; j++) { struct object_entry *child = objects + deltas[j].obj_no; if (child->real_type == OBJ_REF_DELTA) - resolve_delta(child, result, result_size, type); + resolve_delta(child, &result, type); } } @@ -461,11 +466,11 @@ static void resolve_delta(struct object_entry *delta_obj, void *base_data, for (j = first; j <= last; j++) { struct object_entry *child = objects + deltas[j].obj_no; if (child->real_type == OBJ_OFS_DELTA) - resolve_delta(child, result, result_size, type); + resolve_delta(child, &result, type); } } - free(result); + free(result.data); } static int compare_delta_entry(const void *a, const void *b) @@ -480,7 +485,6 @@ static void parse_pack_objects(unsigned char *sha1) { int i; struct delta_entry *delta = deltas; - void *data; struct stat st; /* @@ -495,7 +499,7 @@ static void parse_pack_objects(unsigned char *sha1) nr_objects); for (i = 0; i < nr_objects; i++) { struct object_entry *obj = &objects[i]; - data = unpack_raw_entry(obj, &delta->base); + void *data = unpack_raw_entry(obj, &delta->base); obj->real_type = obj->type; if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) { nr_deltas++; @@ -544,6 +548,7 @@ static void parse_pack_objects(unsigned char *sha1) struct object_entry *obj = &objects[i]; union delta_base base; int j, ref, ref_first, ref_last, ofs, ofs_first, ofs_last; + struct base_data base_obj; if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) continue; @@ -554,22 +559,22 @@ static void parse_pack_objects(unsigned char *sha1) ofs = !find_delta_children(&base, &ofs_first, &ofs_last); if (!ref && !ofs) continue; - data = get_data_from_pack(obj); + base_obj.data = get_data_from_pack(obj); + base_obj.size = obj->size; + if (ref) for (j = ref_first; j <= ref_last; j++) { struct object_entry *child = objects + deltas[j].obj_no; if (child->real_type == OBJ_REF_DELTA) - resolve_delta(child, data, - obj->size, obj->type); + resolve_delta(child, &base_obj, obj->type); } if (ofs) for (j = ofs_first; j <= ofs_last; j++) { struct object_entry *child = objects + deltas[j].obj_no; if (child->real_type == OBJ_OFS_DELTA) - resolve_delta(child, data, - obj->size, obj->type); + resolve_delta(child, &base_obj, obj->type); } - free(data); + free(base_obj.data); display_progress(progress, nr_resolved_deltas); } } @@ -655,28 +660,29 @@ static void fix_unresolved_deltas(int nr_unresolved) for (i = 0; i < n; i++) { struct delta_entry *d = sorted_by_pos[i]; - void *data; - unsigned long size; enum object_type type; int j, first, last; + struct base_data base_obj; if (objects[d->obj_no].real_type != OBJ_REF_DELTA) continue; - data = read_sha1_file(d->base.sha1, &type, &size); - if (!data) + base_obj.data = read_sha1_file(d->base.sha1, &type, &base_obj.size); + if (!base_obj.data) continue; find_delta_children(&d->base, &first, &last); for (j = first; j <= last; j++) { struct object_entry *child = objects + deltas[j].obj_no; if (child->real_type == OBJ_REF_DELTA) - resolve_delta(child, data, size, type); + resolve_delta(child, &base_obj, type); } - if (check_sha1_signature(d->base.sha1, data, size, typename(type))) + if (check_sha1_signature(d->base.sha1, base_obj.data, + base_obj.size, typename(type))) die("local object %s is corrupt", sha1_to_hex(d->base.sha1)); - append_obj_to_pack(d->base.sha1, data, size, type); - free(data); + append_obj_to_pack(d->base.sha1, base_obj.data, + base_obj.size, type); + free(base_obj.data); display_progress(progress, nr_resolved_deltas); } free(sorted_by_pos); -- 2.30.2