[PATCH v2 3/3] index-pack: eliminate unlimited recursion in get_delta_base()
- From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
- Date
- Jan 9, 2012, 03:59 UTC
- Message-ID
- <1326081546-29320-4-git-send-email-pclouds@gmail.com>
- In-Reply-To
- <1324901080-23215-1-git-send-email-pclouds@gmail.com>
Revert the order of delta applying so that by the time a delta is applied, its base is either non-delta or already inflated. get_delta_base() is still recursive, but because base's data is always ready, the inner get_delta_base() call never has any chance to call itself again.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> --- builtin/index-pack.c | 30 +++++++++++++++++++++--------- 1 files changed, 21 insertions(+), 9 deletions(-)
diff --git a/builtin/index-pack.c b/builtin/index-pack.c index 38ff03a..8c1f5d9 100644 --- a/builtin/index-pack.c +++ b/builtin/index-pack.c @@ -519,10 +519,25 @@ static void *get_base_data(struct base_data *c) { if (!c->data) { struct object_entry *obj = c->obj; + struct base_data **delta = NULL; + int delta_nr = 0, delta_alloc = 0; - if (is_delta_type(obj->type)) { - void *base = get_base_data(c->base); - void *raw = get_data_from_pack(obj); + for (; is_delta_type(c->obj->type); c = c->base) { + ALLOC_GROW(delta, delta_nr + 1, delta_alloc); + delta[delta_nr++] = c; + } + if (!delta_nr) { + c->data = get_data_from_pack(obj); + c->size = obj->size; + base_cache_used += c->size; + prune_base_data(c); + } + for (; delta_nr > 0; delta_nr--) { + void *base, *raw; + c = delta[delta_nr - 1]; + obj = c->obj; + base = get_base_data(c->base); + raw = get_data_from_pack(obj); c->data = patch_delta( base, c->base->size, raw, obj->size, @@ -530,13 +545,10 @@ static void *get_base_data(struct base_data *c) free(raw); if (!c->data) bad_object(obj->idx.offset, "failed to apply delta"); - } else { - c->data = get_data_from_pack(obj); - c->size = obj->size; + base_cache_used += c->size; + prune_base_data(c); } - - base_cache_used += c->size; - prune_base_data(c); + free(delta); } return c->data; }
-- 1.7.3.1.256.g2539c.dirty