[sheepdog] [PATCH] collie: cleanup cluster subcommand callbacks when they send empty request

[Yunkai Zhang]

From: Yunkai Zhang <qiushu.zyk at taobao.com>

Cluster subcommand callbacks, such as: cluster_shutdown/cluster_cleanup/...,
share almost the same code, all of them send empty request which only
contains request-header without body content.

So let's abstract the common part of the them into a new function:
send_empty_req() which could make code more compactness.

Signed-off-by: Yunkai Zhang <qiushu.zyk at taobao.com>
---
 collie/cluster.c | 105 +++++++++++++------------------------------------------
 1 file changed, 24 insertions(+), 81 deletions(-)

diff --git a/collie/cluster.c b/collie/cluster.c
index 35bfa23..718f6c4 100644
--- a/collie/cluster.c
+++ b/collie/cluster.c
@@ -202,23 +202,22 @@ error:
 	return EXIT_SYSFAIL;
 }
 
-static int cluster_shutdown(int argc, char **argv)
+/*
+ * Empty request only contains header, without body content.
+ */
+static int send_empty_req(struct sd_req *hdr)
 {
 	int fd, ret;
-	struct sd_req hdr;
-	struct sd_rsp *rsp = (struct sd_rsp *)&hdr;
+	struct sd_rsp *rsp = (struct sd_rsp *)hdr;
 	unsigned rlen, wlen;
 
 	fd = connect_to(sdhost, sdport);
 	if (fd < 0)
 		return EXIT_SYSFAIL;
 
-	sd_init_req(&hdr, SD_OP_SHUTDOWN);
-	hdr.epoch = sd_epoch;
-
 	rlen = 0;
 	wlen = 0;
-	ret = exec_req(fd, &hdr, NULL, &wlen, &rlen);
+	ret = exec_req(fd, hdr, NULL, &wlen, &rlen);
 	close(fd);
 
 	if (ret) {
@@ -227,46 +226,36 @@ static int cluster_shutdown(int argc, char **argv)
 	}
 
 	if (rsp->result != SD_RES_SUCCESS) {
-		fprintf(stderr, "Shutdown failed: %s\n",
-				sd_strerror(rsp->result));
+		fprintf(stderr, "failed: %s\n", sd_strerror(rsp->result));
 		return EXIT_FAILURE;
 	}
 
 	return EXIT_SUCCESS;
 }
 
-static int restore_snap(uint32_t epoch)
+static int cluster_shutdown(int argc, char **argv)
 {
-	int fd, ret;
 	struct sd_req hdr;
-	struct sd_rsp *rsp = (struct sd_rsp *)&hdr;
-	unsigned rlen, wlen;
 
-	fd = connect_to(sdhost, sdport);
-	if (fd < 0)
-		return EXIT_SYSFAIL;
+	sd_init_req(&hdr, SD_OP_SHUTDOWN);
+	hdr.epoch = sd_epoch;
 
-	sd_init_req(&hdr, SD_OP_RESTORE);
-	hdr.obj.tgt_epoch = epoch;
+	return send_empty_req(&hdr);
+}
 
-	rlen = 0;
-	wlen = 0;
-	ret = exec_req(fd, &hdr, NULL, &wlen, &rlen);
-	close(fd);
+static int restore_snap(uint32_t epoch)
+{
+	int ret;
+	struct sd_req hdr;
 
-	if (ret) {
-		fprintf(stderr, "Failed to connect\n");
-		return EXIT_SYSFAIL;
-	}
+	sd_init_req(&hdr, SD_OP_RESTORE);
+	hdr.obj.tgt_epoch = epoch;
 
-	if (rsp->result != SD_RES_SUCCESS) {
-		fprintf(stderr, "Restore failed: %s\n",
-				sd_strerror(rsp->result));
-		return EXIT_FAILURE;
-	}
+	ret = send_empty_req(&hdr);
+	if (ret == EXIT_SUCCESS)
+		printf("Cluster restore to the snapshot %d\n", epoch);
 
-	printf("Cluster restore to the snapshot %d\n", epoch);
-	return EXIT_SUCCESS;
+	return ret;
 }
 
 static void print_list(void *buf, unsigned len)
@@ -327,34 +316,11 @@ out:
 
 static int do_snapshot(void)
 {
-	int fd, ret;
 	struct sd_req hdr;
-	struct sd_rsp *rsp = (struct sd_rsp *)&hdr;
-	unsigned rlen, wlen;
-
-	fd = connect_to(sdhost, sdport);
-	if (fd < 0)
-		return EXIT_SYSFAIL;
 
 	sd_init_req(&hdr, SD_OP_SNAPSHOT);
 
-	rlen = 0;
-	wlen = 0;
-	ret = exec_req(fd, &hdr, NULL, &wlen, &rlen);
-	close(fd);
-
-	if (ret) {
-		fprintf(stderr, "Failed to connect\n");
-		return EXIT_SYSFAIL;
-	}
-
-	if (rsp->result != SD_RES_SUCCESS) {
-		fprintf(stderr, "Snapshot failed: %s\n",
-				sd_strerror(rsp->result));
-		return EXIT_FAILURE;
-	}
-
-	return EXIT_SUCCESS;
+	return send_empty_req(&hdr);
 }
 
 static int cluster_snapshot(int argc, char **argv)
@@ -371,34 +337,11 @@ static int cluster_snapshot(int argc, char **argv)
 
 static int cluster_cleanup(int argc, char **argv)
 {
-	int fd, ret;
 	struct sd_req hdr;
-	struct sd_rsp *rsp = (struct sd_rsp *)&hdr;
-	unsigned rlen, wlen;
-
-	fd = connect_to(sdhost, sdport);
-	if (fd < 0)
-		return EXIT_SYSFAIL;
 
 	sd_init_req(&hdr, SD_OP_CLEANUP);
 
-	rlen = 0;
-	wlen = 0;
-	ret = exec_req(fd, &hdr, NULL, &wlen, &rlen);
-	close(fd);
-
-	if (ret) {
-		fprintf(stderr, "Failed to connect\n");
-		return EXIT_SYSFAIL;
-	}
-
-	if (rsp->result != SD_RES_SUCCESS) {
-		fprintf(stderr, "Cleanup failed: %s\n",
-				sd_strerror(rsp->result));
-		return EXIT_FAILURE;
-	}
-
-	return EXIT_SUCCESS;
+	return send_empty_req(&hdr);
 }
 
 #define RECOVER_PRINT \
-- 
1.7.11.2