Unify use of error codes across all exit statements

CREDITS

@@ -8,3 +8,4 @@ Gabriele Bartolini <gabriele@2ndQuadrant.com>
 Bas van Oostveen <v.oostveen@gmail.com>
 Hannu Krosing <hannu@2ndQuadrant.com>
 Cédric Villemain <cedric@2ndquadrant.fr>
+Charles Duffy <charles@dyfis.net>

HISTORY

@@ -1,4 +1,4 @@
-1.0.0 2010-12-05 First public release
+1.0.0 2010-12-05 First public release (Greg Smith)
 
 1.0.1 2011-02-XX Fix missing "--force" option in help
                	 Correct warning message for wal_keep_segments (Bas van Oostveen)
@@ -13,4 +13,6 @@
                  Avoid buffer overruns by using snprintf etc. (Gabriele)
                  Fix use of database query after close (Gabriele)
                  Add information about progress during "standby clone" (Gabriele)
-
+                 Fix double free error in repmgrd (Charles Duffy)
+                 Make repmgr exit with an error code when encountering an error (Charles)
+                 Standardize on error return codes, use in repmgrd too (Greg) 

README.rst

@@ -539,6 +539,23 @@ and the same in the standby.
 The repmgr daemon creates 2 connections: one to the master and another to the
 standby.
 
+Error codes
+-----------
+
+When the repmgr or repmgrd program exits, it will set one of the
+following 
+
+* SUCCESS 0:  Program ran successfully.
+
+* ERR_BAD_CONFIG 1:  One of the configuration checks the program makes failed.
+* ERR_BAD_RSYNC 2:  An rsync call made by the program returned an error.
+* ERR_STOP_BACKUP 3:  A ``pg_stop_backup()`` call made by the program didn't succeed.
+* ERR_NO_RESTART 4:  An attempt to restart a PostgreSQL instance failed.
+* ERR_NEEDS_XLOG 5:  Could note create the ``pg_xlog`` directory when cloning.
+* ERR_DB_CON 6:  Error when trying to connect to a database.
+* ERR_DB_QUERY 7:  Error executing a database query.
+* ERR_PROMOTED 8:  Exiting program because the node has been promoted to master.
+
 Detailed walkthrough
 ====================
 

config.c

@@ -30,7 +30,7 @@ parse_config(const char* config_file, t_configuration_options* options)
 
 	if (fp == NULL) {
 		fprintf(stderr, _("Could not find configuration file '%s'\n"), config_file);
-		exit(1);
+		exit(ERR_BAD_CONFIG);
 	}
 
 	/* Initialize */
@@ -75,14 +75,14 @@ parse_config(const char* config_file, t_configuration_options* options)
 	{
 		fprintf(stderr, "Cluster name is missing. "
 		        "Check the configuration file.\n");
-		exit(1);
+		exit(ERR_BAD_CONFIG);
 	}
 
 	if (config->node == -1)
 	{
 		fprintf(stderr, "Node information is missing. "
 		        "Check the configuration file.\n");
-		exit(1);
+		exit(ERR_BAD_CONFIG);
 	}
 }
 

dbutils.c

@@ -36,7 +36,7 @@ establishDBConnection(const char *conninfo, const bool exit_on_error)
 		if (exit_on_error)
 		{
 			PQfinish(conn);
-			exit(1);
+			exit(ERR_DB_CON);
 		}
 	}
 
@@ -57,7 +57,7 @@ is_standby(PGconn *conn)
 		fprintf(stderr, "Can't query server mode: %s", PQerrorMessage(conn));
 		PQclear(res);
 		PQfinish(conn);
-		exit(1);
+		exit(ERR_NO_DB_CON);
 	}
 
 	if (strcmp(PQgetvalue(res, 0, 0), "f") == 0)
@@ -89,7 +89,7 @@ pg_version(PGconn *conn, char* major_version)
 		fprintf(stderr, "PQexec failed: %s", PQerrorMessage(conn));
 		PQclear(res);
 		PQfinish(conn);
-		exit(1);
+		exit(ERR_DB_QUERY);
 	}
 	major_version1 = atoi(PQgetvalue(res, 0, 0));
 	major_version2 = PQgetvalue(res, 0, 1);
@@ -123,7 +123,7 @@ guc_setted(PGconn *conn, const char *parameter, const char *op, const char *valu
 		fprintf(stderr, "PQexec failed: %s", PQerrorMessage(conn));
 		PQclear(res);
 		PQfinish(conn);
-		exit(1);
+		exit(ERR_DB_QUERY);
 	}
 	if (PQntuples(res) == 0)
 	{
@@ -152,7 +152,7 @@ get_cluster_size(PGconn *conn)
 		fprintf(stderr, "PQexec failed: %s", PQerrorMessage(conn));
 		PQclear(res);
 		PQfinish(conn);
-		exit(1);
+		exit(ERR_DB_QUERY);
 	}
 	size = PQgetvalue(res, 0, 0);
 	PQclear(res);
@@ -184,7 +184,7 @@ getMasterConnection(PGconn *standby_conn, int id, char *cluster, int *master_id)
 		fprintf(stderr, "Can't get nodes info: %s\n", PQerrorMessage(standby_conn));
 		PQclear(res1);
 		PQfinish(standby_conn);
-		exit(1);
+		exit(ERR_DB_QUERY);
 	}
 
 	for (i = 0; i < PQntuples(res1); i++)

repmgr.c

@@ -101,12 +101,12 @@ main(int argc, char **argv)
 		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
 		{
 			help(progname);
-			exit(0);
+			exit(SUCCESS);
 		}
 		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
 		{
 			printf("%s (PostgreSQL) " PG_VERSION "\n", progname);
-			exit(0);
+			exit(SUCCESS);
 		}
 	}
 

repmgr.h

@@ -47,11 +47,15 @@
 
 /* Exit return code */
 
+#define SUCCESS 0
 #define ERR_BAD_CONFIG 1
 #define ERR_BAD_RSYNC 2
 #define ERR_STOP_BACKUP 3
 #define ERR_NO_RESTART 4
 #define ERR_NEEDS_XLOG 5
+#define ERR_DB_CON 6
+#define ERR_DB_QUERY 7
+#define ERR_PROMOTED 8
 
 /* Run time options type */
 typedef struct {

repmgrd.c

@@ -107,12 +107,12 @@ main(int argc, char **argv)
 		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
 		{
 			help(progname);
-			exit(0);
+			exit(SUCCESS);
 		}
 		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
 		{
 			printf("%s (PostgreSQL) " PG_VERSION "\n", progname);
-			exit(0);
+			exit(SUCCESS);
 		}
 	}
 
@@ -129,7 +129,7 @@ main(int argc, char **argv)
 			break;
 		default:
 			usage();
-			exit(1);
+			exit(ERR_BAD_CONFIG);
 		}
 	}
 
@@ -143,7 +143,7 @@ main(int argc, char **argv)
 	{
 		log_err("Node information is missing. "
 		        "Check the configuration file.\n");
-		exit(1);
+		exit(ERR_BAD_CONFIG);
 	}
 	logger_init(progname, local_options.loglevel, local_options.logfacility);
 	snprintf(repmgr_schema, MAXLEN, "%s%s", DEFAULT_REPMGR_SCHEMA_PREFIX, local_options.cluster_name);
@@ -156,7 +156,7 @@ main(int argc, char **argv)
 	{
 		PQfinish(myLocalConn);
 		log_err(_("%s needs standby to be PostgreSQL 9.0 or better\n"), progname);
-		exit(1);
+		exit(ERR_BAD_CONFIG);
 	}
 
 	/*
@@ -175,7 +175,7 @@ main(int argc, char **argv)
 		/* I need the id of the primary as well as a connection to it */
 		primaryConn = getMasterConnection(myLocalConn, local_options.node, local_options.cluster_name, &primary_options.node);
 		if (primaryConn == NULL)
-			exit(1);
+			exit(ERR_BAD_CONFIG);
 	}
 
 	checkClusterConfiguration();
@@ -258,15 +258,15 @@ MonitorExecute(void)
 	if (PQstatus(primaryConn) != CONNECTION_OK)
 	{
 		log_err(_("We couldn't reconnect for long enough, exiting..."));
-		exit(1);
+		exit(ERR_DB_CON);
 	}
 
 	/* Check if we still are a standby, we could have been promoted */
 	if (!is_standby(myLocalConn))
 	{
 		log_err(_("It seems like we have been promoted, so exit from monitoring..."));
 		CloseConnections();
-		exit(1);
+		exit(ERR_PROMOTED);
 	}
 
 	/*
@@ -354,7 +354,7 @@ checkClusterConfiguration(void)
 		PQclear(res);
 		PQfinish(myLocalConn);
 		PQfinish(primaryConn);
-		exit(1);
+		exit(ERR_DB_QUERY);
 	}
 
 	/*
@@ -368,7 +368,7 @@ checkClusterConfiguration(void)
 		PQclear(res);
 		PQfinish(myLocalConn);
 		PQfinish(primaryConn);
-		exit(1);
+		exit(ERR_BAD_CONFIG);
 	}
 	PQclear(res);
 }
@@ -393,7 +393,7 @@ checkNodeConfiguration(char *conninfo)
 		PQclear(res);
 		PQfinish(myLocalConn);
 		PQfinish(primaryConn);
-		exit(1);
+		exit(ERR_BAD_CONFIG);
 	}
 
 	/*
@@ -414,7 +414,7 @@ checkNodeConfiguration(char *conninfo)
 			        PQerrorMessage(primaryConn));
 			PQfinish(myLocalConn);
 			PQfinish(primaryConn);
-			exit(1);
+			exit(ERR_BAD_CONFIG);
 		}
 	}
 	PQclear(res);