pgpool2.git / summary / log / commit / refs

commit    78240da96f4a975907cebada8be236387d6e272b
Author:   Tatsuo Ishii <ishii at sraoss.co.jp>
Date:     Sun Dec 06 12:55:08 2009 +0000

    Restore backend status by using pgpool_status file.


 main.c      | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 pool.h      |  3 +++
 pool_type.h |  7 ++++++
 3 files changed, 92 insertions(+)

diff --git a/main.c b/main.c
index ab047ee35..da75fc9bb 100644
--- a/main.c
+++ b/main.c
@@ -84,6 +84,8 @@
 static void daemonize(void);
 static int read_pid_file(void);
 static void write_pid_file(void);
+static int read_status_file(void);
+static int write_statusd_file(void);
 static pid_t pcp_fork_a_child(int unix_fd, int inet_fd, char *pcp_conf_file);
 static pid_t fork_a_child(int unix_fd, int inet_fd, int id);
 static int create_unix_domain_socket(struct sockaddr_un un_addr_tmp);
@@ -163,6 +165,8 @@ static int pipe_fds[2]; /* for delivering signals */
 
 int my_proc_id;
 
+static BackendStatusRecord backend_rec;	/* Backend status record */
+
 int myargc;
 char **myargv;
 
@@ -356,6 +360,11 @@ int main(int argc, char **argv)
 		exit(1);
 	}
 
+	/*
+	 * Restore previous backend status if possible
+	 */
+	read_status_file();
+
 	/* clear cache */
 	if (clear_cache && pool_config->enable_query_cache && SYSDB_STATUS == CON_UP)
 	{
@@ -773,6 +782,77 @@ static void write_pid_file(void)
 	}
 }
 
+/*
+* Read the status file
+*/
+static int read_status_file(void)
+{
+	FILE *fd;
+	char fnamebuf[POOLMAXPATHLEN];
+	int i;
+
+	snprintf(fnamebuf, sizeof(fnamebuf), "%s/%s", pool_config->logdir, STATUS_FILE_NAME);
+	fd = fopen(fnamebuf, "r");
+	if (!fd)
+	{
+		pool_log("Backend status file %s does not exist", fnamebuf);
+		return -1;
+	}
+	if (fread(&backend_rec, 1, sizeof(backend_rec), fd) <= 0)
+	{
+		pool_error("Could not read backend status file as %s. reason: %s",
+				   fnamebuf, strerror(errno));
+		fclose(fd);
+		return -1;
+	}
+	fclose(fd);
+
+	for (i=0;i< pool_config->backend_desc->num_backends;i++)
+	{
+		if (backend_rec.status[i] == CON_DOWN)
+			BACKEND_INFO(i).backend_status = CON_DOWN;
+		else
+			BACKEND_INFO(i).backend_status = CON_CONNECT_WAIT;
+	}
+
+	return 0;
+}
+
+/*
+* Write the pid file
+*/
+static int write_status_file(void)
+{
+	FILE *fd;
+	char fnamebuf[POOLMAXPATHLEN];
+	int i;
+
+	snprintf(fnamebuf, sizeof(fnamebuf), "%s/%s", pool_config->logdir, STATUS_FILE_NAME);
+	fd = fopen(fnamebuf, "w");
+	if (!fd)
+	{
+		pool_error("Could not open status file %s", fnamebuf);
+		return -1;
+	}
+
+	memset(&backend_rec, 0, sizeof(backend_rec));
+
+	for (i=0;i< pool_config->backend_desc->num_backends;i++)
+	{
+		backend_rec.status[i] = BACKEND_INFO(i).backend_status;
+	}
+
+	if (fwrite(&backend_rec, 1, sizeof(backend_rec), fd) <= 0)
+	{
+		pool_error("Could not write backend status file as %s. reason: %s",
+				   fnamebuf, strerror(errno));
+		fclose(fd);
+		return -1;
+	}
+	fclose(fd);
+	return 0;
+}
+
 /*
  * fork a child for PCP
  */
@@ -993,6 +1073,8 @@ static void myexit(int code)
 	myunlink(pcp_un_addr.sun_path);
 	myunlink(pool_config->pid_file_name);
 
+	write_status_file();
+
 	pool_shmem_exit(code);
 	exit(code);
 }
diff --git a/pool.h b/pool.h
index bddbe6909..8e93b7640 100644
--- a/pool.h
+++ b/pool.h
@@ -58,6 +58,9 @@
 /* pid file name */
 #define DEFAULT_PID_FILE_NAME "/var/run/pgpool/pgpool.pid"
 
+/* status file name */
+#define STATUS_FILE_NAME "pgpool_status"
+
 typedef enum {
 	POOL_CONTINUE = 0,
 	POOL_IDLE,
diff --git a/pool_type.h b/pool_type.h
index b3092a24b..512f89b47 100644
--- a/pool_type.h
+++ b/pool_type.h
@@ -189,6 +189,13 @@ typedef struct {
 	BACKEND_STATUS system_db_status;
 } SystemDBInfo;
 
+/*
+ * Backend status record file
+ */
+typedef struct {
+	BACKEND_STATUS status[MAX_NUM_BACKENDS];
+} BackendStatusRecord;
+
 /*
  *  It seems that sockaddr_storage is now commonly used in place of sockaddr.
  *  So, define it if it is not define yet, and create new SockAddr structure


[parent: f9ec1067dbf9]