Simplify mru.[ch] and related code by reusing the double-linked list
implementation from list.h instead of a custom one.
This commit is an intermediate step. Our final goal is to get rid of
mru.[ch] at all and inline all logic.
Signed-off-by: Olga Telezhnaia <olyatelezhnaya@xxxxxxxxx>
Mentored-by: Christian Couder <christian.couder@xxxxxxxxx>
Mentored by: Jeff King <peff@xxxxxxxx>
---
builtin/pack-objects.c | 5 +++--
mru.c | 49 +++++++++++++------------------------------------
mru.h | 31 +++++++++++++------------------
packfile.c | 7 ++++---
4 files changed, 33 insertions(+), 59 deletions(-)
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index f721137eaf881..ba812349e0aab 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -995,8 +995,8 @@ static int want_object_in_pack(const unsigned char *sha1,
struct packed_git **found_pack,
off_t *found_offset)
{
- struct mru_entry *entry;
int want;
+ struct list_head *pos;
if (!exclude && local && has_loose_object_nonlocal(sha1))
return 0;
@@ -1012,7 +1012,8 @@ static int want_object_in_pack(const unsigned char *sha1,
return want;
}
- for (entry = packed_git_mru.head; entry; entry = entry->next) {
+ list_for_each(pos, &packed_git_mru.list) {
+ struct mru *entry = list_entry(pos, struct mru, list);
struct packed_git *p = entry->item;
off_t offset;
diff --git a/mru.c b/mru.c
index 9dedae0287ed2..8f3f34c5ba91d 100644
--- a/mru.c
+++ b/mru.c
@@ -1,50 +1,27 @@
#include "cache.h"
#include "mru.h"
-void mru_append(struct mru *mru, void *item)
+void mru_append(struct mru *head, void *item)
{
- struct mru_entry *cur = xmalloc(sizeof(*cur));
+ struct mru *cur = xmalloc(sizeof(*cur));
cur->item = item;
- cur->prev = mru->tail;
- cur->next = NULL;
-
- if (mru->tail)
- mru->tail->next = cur;
- else
- mru->head = cur;
- mru->tail = cur;
+ list_add_tail(&cur->list, &head->list);
}
-void mru_mark(struct mru *mru, struct mru_entry *entry)
+void mru_mark(struct mru *head, struct mru *entry)
{
- /* If we're already at the front of the list, nothing to do */
- if (mru->head == entry)
- return;
-
- /* Otherwise, remove us from our current slot... */
- if (entry->prev)
- entry->prev->next = entry->next;
- if (entry->next)
- entry->next->prev = entry->prev;
- else
- mru->tail = entry->prev;
-
- /* And insert us at the beginning. */
- entry->prev = NULL;
- entry->next = mru->head;
- if (mru->head)
- mru->head->prev = entry;
- mru->head = entry;
+ /* To mark means to put at the front of the list. */
+ list_del(&entry->list);
+ list_add(&entry->list, &head->list);
}
-void mru_clear(struct mru *mru)
+void mru_clear(struct mru *head)
{
- struct mru_entry *p = mru->head;
+ struct list_head *pos;
+ struct list_head *tmp;
- while (p) {
- struct mru_entry *to_free = p;
- p = p->next;
- free(to_free);
+ list_for_each_safe(pos, tmp, &head->list) {
+ free(list_entry(pos, struct mru, list));
}
- mru->head = mru->tail = NULL;
+ INIT_LIST_HEAD(&head->list);
}
diff --git a/mru.h b/mru.h
index 42e4aeaa1098a..80a589eb4c0eb 100644
--- a/mru.h
+++ b/mru.h
@@ -1,6 +1,8 @@
#ifndef MRU_H
#define MRU_H
+#include "list.h"
+
/**
* A simple most-recently-used cache, backed by a doubly-linked list.
*
@@ -8,18 +10,15 @@
*
* // Create a list. Zero-initialization is required.
* static struct mru cache;
- * mru_append(&cache, item);
- * ...
+ * INIT_LIST_HEAD(&cache.list);
*
- * // Iterate in MRU order.
- * struct mru_entry *p;
- * for (p = cache.head; p; p = p->next) {
- * if (matches(p->item))
- * break;
- * }
+ * // Add new item to the end of the list.
+ * void *item;
+ * ...
+ * mru_append(&cache, item);
*
* // Mark an item as used, moving it to the front of the list.
- * mru_mark(&cache, p);
+ * mru_mark(&cache, item);
*
* // Reset the list to empty, cleaning up all resources.
* mru_clear(&cache);
@@ -29,17 +28,13 @@
* you will begin traversing the whole list again.
*/
-struct mru_entry {
- void *item;
- struct mru_entry *prev, *next;
-};
-
struct mru {
- struct mru_entry *head, *tail;
+ struct list_head list;
+ void *item;
};
-void mru_append(struct mru *mru, void *item);
-void mru_mark(struct mru *mru, struct mru_entry *entry);
-void mru_clear(struct mru *mru);
+void mru_append(struct mru *head, void *item);
+void mru_mark(struct mru *head, struct mru *entry);
+void mru_clear(struct mru *head);
#endif /* MRU_H */
diff --git a/packfile.c b/packfile.c
index f69a5c8d607af..502d915991bee 100644
--- a/packfile.c
+++ b/packfile.c
@@ -40,7 +40,7 @@ static unsigned int pack_max_fds;
static size_t peak_pack_mapped;
static size_t pack_mapped;
struct packed_git *packed_git;
-struct mru packed_git_mru;
+struct mru packed_git_mru = {{&packed_git_mru.list, &packed_git_mru.list}};
#define SZ_FMT PRIuMAX
static inline uintmax_t sz_fmt(size_t s) { return s; }
@@ -1824,13 +1824,14 @@ static int fill_pack_entry(const unsigned char *sha1,
*/
int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
{
- struct mru_entry *p;
+ struct list_head *pos;
prepare_packed_git();
if (!packed_git)
return 0;
- for (p = packed_git_mru.head; p; p = p->next) {
+ list_for_each(pos, &packed_git_mru.list) {
+ struct mru *p = list_entry(pos, struct mru, list);
if (fill_pack_entry(sha1, e, p->item)) {
mru_mark(&packed_git_mru, p);
return 1;
--
https://github.com/git/git/pull/409
