[sheepdog] [PATCH 1/4] dog/farm: kill snap file

[Liu Yuan]

snap file is used to store [idx, trunk_sha1] pairs, but since we already have
sha1 information in struct snap_log, we don't need it at all and we can directly
store trunk sha1 in snap_log.

Signed-off-by: Liu Yuan <namei.unix at gmail.com>
---
 dog/farm/farm.c | 13 ++-----------
 dog/farm/farm.h | 10 +---------
 dog/farm/snap.c | 19 +------------------
 3 files changed, 4 insertions(+), 38 deletions(-)

diff --git a/dog/farm/farm.c b/dog/farm/farm.c
index 7d93406..c5af9ed 100644
--- a/dog/farm/farm.c
+++ b/dog/farm/farm.c
@@ -176,7 +176,6 @@ static int get_trunk_sha1(uint32_t idx, const char *tag, unsigned char *outsha1)
 {
 	int nr_logs = -1, ret = -1;
 	struct snap_log *log_buf, *log_free = NULL;
-	struct snap_file *snap_buf = NULL;
 
 	log_free = log_buf = snap_log_read(&nr_logs);
 	if (nr_logs < 0)
@@ -185,16 +184,12 @@ static int get_trunk_sha1(uint32_t idx, const char *tag, unsigned char *outsha1)
 	for (int i = 0; i < nr_logs; i++, log_buf++) {
 		if (log_buf->idx != idx && strcmp(log_buf->tag, tag))
 			continue;
-		snap_buf = snap_file_read(log_buf->sha1);
-		if (!snap_buf)
-			goto out;
-		memcpy(outsha1, snap_buf->trunk_sha1, SHA1_DIGEST_SIZE);
+		memcpy(outsha1, log_buf->trunk_sha1, SHA1_DIGEST_SIZE);
 		ret = 0;
 		goto out;
 	}
 out:
 	free(log_free);
-	free(snap_buf);
 	return ret;
 }
 
@@ -314,7 +309,6 @@ static int queue_save_snapshot_work(uint64_t oid, uint32_t nr_copies,
 
 int farm_save_snapshot(const char *tag)
 {
-	unsigned char snap_sha1[SHA1_DIGEST_SIZE];
 	unsigned char trunk_sha1[SHA1_DIGEST_SIZE];
 	struct strbuf trunk_buf;
 	void *snap_log = NULL;
@@ -342,10 +336,7 @@ int farm_save_snapshot(const char *tag)
 			     trunk_sha1) < 0)
 		goto out;
 
-	if (snap_file_write(idx, trunk_sha1, snap_sha1) < 0)
-		goto out;
-
-	if (snap_log_write(idx, tag, snap_sha1) < 0)
+	if (snap_log_write(idx, tag, trunk_sha1) < 0)
 		goto out;
 
 	ret = 0;
diff --git a/dog/farm/farm.h b/dog/farm/farm.h
index c045845..e838a58 100644
--- a/dog/farm/farm.h
+++ b/dog/farm/farm.h
@@ -31,16 +31,11 @@ struct trunk_file {
 	struct trunk_entry *entries;
 };
 
-struct snap_file {
-	int idx;
-	unsigned char trunk_sha1[SHA1_DIGEST_SIZE];
-};
-
 struct snap_log {
 	uint32_t idx;
 	char tag[SD_MAX_SNAPSHOT_TAG_LEN];
 	uint64_t time;
-	unsigned char sha1[SHA1_DIGEST_SIZE];
+	unsigned char trunk_sha1[SHA1_DIGEST_SIZE];
 };
 
 /* farm.c */
@@ -61,9 +56,6 @@ uint64_t trunk_get_count(void);
 
 /* snap.c */
 int snap_init(const char *path);
-struct snap_file *snap_file_read(unsigned char *sha1);
-int snap_file_write(uint32_t idx, unsigned char *trunk_sha1,
-		    unsigned char *outsha1);
 void *snap_log_read(int *out_nr);
 int snap_log_write(uint32_t idx, const char *tag, unsigned char *sha1);
 
diff --git a/dog/farm/snap.c b/dog/farm/snap.c
index 8c46484..5e889d7 100644
--- a/dog/farm/snap.c
+++ b/dog/farm/snap.c
@@ -56,7 +56,7 @@ int snap_log_write(uint32_t idx, const char *tag, unsigned char *sha1)
 	struct snap_log log = { .idx = idx,
 				.time = time(NULL) };
 	pstrcpy(log.tag, SD_MAX_SNAPSHOT_TAG_LEN, tag);
-	memcpy(log.sha1, sha1, SHA1_DIGEST_SIZE);
+	memcpy(log.trunk_sha1, sha1, SHA1_DIGEST_SIZE);
 
 	fd = open(snap_log_path, O_WRONLY | O_APPEND);
 	if (fd < 0) {
@@ -108,20 +108,3 @@ out_close:
 out:
 	return buffer;
 }
-
-struct snap_file *snap_file_read(unsigned char *sha1)
-{
-	size_t size;
-	return sha1_file_read(sha1, &size);
-}
-
-int snap_file_write(uint32_t idx, unsigned char *trunk_sha1,
-		    unsigned char *outsha1)
-{
-	struct snap_file snap;
-	snap.idx = idx;
-	memcpy(snap.trunk_sha1, trunk_sha1, SHA1_DIGEST_SIZE);
-
-	return sha1_file_write(&snap, sizeof(struct snap_file),
-			       outsha1);
-}
-- 
1.8.1.2