This is refactoring 2 of 2 to simplify struct base_data.
Whenever we make a struct base_data, immediately calculate its delta
children. This eliminates confusion as to when the
{ref,ofs}_{first,last} fields are initialized.
Before this patch, the delta children were calculated at the last
possible moment. This allowed the members of struct base_data to be
populated in any order, superficially useful when we have the object
contents before the struct object_entry. But this makes reasoning about
the state of struct base_data more complicated, hence this patch.
Signed-off-by: Jonathan Tan <jonathantanmy@xxxxxxxxxx>
---
builtin/index-pack.c | 125 +++++++++++++++++++++----------------------
1 file changed, 61 insertions(+), 64 deletions(-)
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index 220e1e3693..d21353757d 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -33,12 +33,15 @@ struct object_stat {
};
struct base_data {
+ /* Initialized by make_base(). */
struct base_data *base;
struct object_entry *obj;
- void *data;
- unsigned long size;
int ref_first, ref_last;
int ofs_first, ofs_last;
+
+ /* Not initialized by make_base(). */
+ void *data;
+ unsigned long size;
};
struct thread_local {
@@ -362,14 +365,6 @@ static void set_thread_data(struct thread_local *data)
pthread_setspecific(key, data);
}
-static struct base_data *alloc_base_data(void)
-{
- struct base_data *base = xcalloc(1, sizeof(struct base_data));
- base->ref_last = -1;
- base->ofs_last = -1;
- return base;
-}
-
static void free_base_data(struct base_data *c)
{
if (c->data) {
@@ -406,19 +401,6 @@ static void prune_base_data(struct base_data *youngest_child)
free(ancestry);
}
-static void link_base_data(struct base_data *base, struct base_data *c)
-{
- c->base = base;
- if (c->data)
- get_thread_data()->base_cache_used += c->size;
- prune_base_data(c);
-}
-
-static void unlink_base_data(struct base_data *c)
-{
- free_base_data(c);
-}
-
static int is_delta_type(enum object_type type)
{
return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
@@ -928,10 +910,25 @@ static void *get_base_data(struct base_data *c)
return c->data;
}
-static void resolve_delta(struct object_entry *delta_obj,
- struct base_data *base, struct base_data *result)
+static struct base_data *make_base(struct object_entry *obj,
+ struct base_data *parent)
{
- void *base_data, *delta_data;
+ struct base_data *base = xcalloc(1, sizeof(struct base_data));
+ base->base = parent;
+ base->obj = obj;
+ find_ref_delta_children(&obj->idx.oid,
+ &base->ref_first, &base->ref_last);
+ find_ofs_delta_children(obj->idx.offset,
+ &base->ofs_first, &base->ofs_last);
+ return base;
+}
+
+static struct base_data *resolve_delta(struct object_entry *delta_obj,
+ struct base_data *base)
+{
+ void *base_data, *delta_data, *result_data;
+ struct base_data *result;
+ unsigned long result_size;
if (show_stat) {
int i = delta_obj - objects;
@@ -945,19 +942,31 @@ static void resolve_delta(struct object_entry *delta_obj,
}
delta_data = get_data_from_pack(delta_obj);
base_data = get_base_data(base);
- result->obj = delta_obj;
- result->data = patch_delta(base_data, base->size,
- delta_data, delta_obj->size, &result->size);
+ result_data = patch_delta(base_data, base->size,
+ delta_data, delta_obj->size, &result_size);
free(delta_data);
- if (!result->data)
+ if (!result_data)
bad_object(delta_obj->idx.offset, _("failed to apply delta"));
- hash_object_file(result->data, result->size,
+ hash_object_file(result_data, result_size,
type_name(delta_obj->real_type), &delta_obj->idx.oid);
- sha1_object(result->data, NULL, result->size, delta_obj->real_type,
+ sha1_object(result_data, NULL, result_size, delta_obj->real_type,
&delta_obj->idx.oid);
+
+ result = make_base(delta_obj, base);
+ if (result->ref_last == -1 && result->ofs_last == -1) {
+ free(result_data);
+ } else {
+ result->data = result_data;
+ result->size = result_size;
+ get_thread_data()->base_cache_used += result->size;
+ prune_base_data(result);
+ }
+
counter_lock();
nr_resolved_deltas++;
counter_unlock();
+
+ return result;
}
/*
@@ -983,30 +992,15 @@ static int compare_and_swap_type(signed char *type,
static struct base_data *find_unresolved_deltas_1(struct base_data *base,
struct base_data *prev_base)
{
- if (base->ref_last == -1 && base->ofs_last == -1) {
- find_ref_delta_children(&base->obj->idx.oid,
- &base->ref_first, &base->ref_last);
-
- find_ofs_delta_children(base->obj->idx.offset,
- &base->ofs_first, &base->ofs_last);
-
- if (base->ref_last == -1 && base->ofs_last == -1) {
- free(base->data);
- return NULL;
- }
-
- link_base_data(prev_base, base);
- }
-
if (base->ref_first <= base->ref_last) {
struct object_entry *child = objects + ref_deltas[base->ref_first].obj_no;
- struct base_data *result = alloc_base_data();
+ struct base_data *result;
if (!compare_and_swap_type(&child->real_type, OBJ_REF_DELTA,
base->obj->real_type))
BUG("child->real_type != OBJ_REF_DELTA");
- resolve_delta(child, base, result);
+ result = resolve_delta(child, base);
if (base->ref_first == base->ref_last && base->ofs_last == -1)
free_base_data(base);
@@ -1016,11 +1010,11 @@ static struct base_data *find_unresolved_deltas_1(struct base_data *base,
if (base->ofs_first <= base->ofs_last) {
struct object_entry *child = objects + ofs_deltas[base->ofs_first].obj_no;
- struct base_data *result = alloc_base_data();
+ struct base_data *result;
assert(child->real_type == OBJ_OFS_DELTA);
child->real_type = base->obj->real_type;
- resolve_delta(child, base, result);
+ result = resolve_delta(child, base);
if (base->ofs_first == base->ofs_last)
free_base_data(base);
@@ -1028,7 +1022,7 @@ static struct base_data *find_unresolved_deltas_1(struct base_data *base,
return result;
}
- unlink_base_data(base);
+ free_base_data(base);
return NULL;
}
@@ -1071,9 +1065,8 @@ static int compare_ref_delta_entry(const void *a, const void *b)
static void resolve_base(struct object_entry *obj)
{
- struct base_data *base_obj = alloc_base_data();
- base_obj->obj = obj;
- base_obj->data = NULL;
+ struct base_data *base_obj = make_base(obj, NULL);
+
find_unresolved_deltas(base_obj);
}
@@ -1367,21 +1360,25 @@ static void fix_unresolved_deltas(struct hashfile *f)
for (i = 0; i < nr_ref_deltas; i++) {
struct ref_delta_entry *d = sorted_by_pos[i];
enum object_type type;
- struct base_data *base_obj = alloc_base_data();
+ struct base_data *base;
+ void *data;
+ unsigned long size;
+ struct object_entry *obj;
if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
continue;
- base_obj->data = read_object_file(&d->oid, &type,
- &base_obj->size);
- if (!base_obj->data)
+ data = read_object_file(&d->oid, &type, &size);
+ if (!data)
continue;
- if (check_object_signature(&d->oid, base_obj->data,
- base_obj->size, type_name(type)))
+ if (check_object_signature(&d->oid, data,
+ size, type_name(type)))
die(_("local object %s is corrupt"), oid_to_hex(&d->oid));
- base_obj->obj = append_obj_to_pack(f, d->oid.hash,
- base_obj->data, base_obj->size, type);
- find_unresolved_deltas(base_obj);
+ obj = append_obj_to_pack(f, d->oid.hash, data, size, type);
+ base = make_base(obj, NULL);
+ base->data = data;
+ base->size = size;
+ find_unresolved_deltas(base);
display_progress(progress, nr_resolved_deltas);
}
free(sorted_by_pos);
--
2.23.0.866.gb869b98d4c-goog
