Fix compilation of all bgworkers with Postgres >= 10

Upstream commit 2113ac4c has removed bgw_main field from the bgworker
registration worker, so adapt all the modules to this new rule.

count_relations/count_relations.c

@@ -34,6 +34,7 @@
 PG_MODULE_MAGIC;
 void _PG_init(void);
+void count_relations_main(Datum main_arg);
 static volatile sig_atomic_t got_sigterm = false;
@@ -57,7 +58,7 @@ count_relations_sighup(SIGNAL_ARGS)
 		SetLatch(&MyProc->procLatch);
 }
-static void
+void
 count_relations_main(Datum main_arg)
 {
 	/* Register functions for SIGTERM/SIGHUP management */
@@ -141,7 +142,8 @@ _PG_init(void)
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_RecoveryFinished;
-	worker.bgw_main = count_relations_main;
+	snprintf(worker.bgw_library_name, BGW_MAXLEN, "count_relations");
+	snprintf(worker.bgw_function_name, BGW_MAXLEN, "count_relations_main");
 	snprintf(worker.bgw_name, BGW_MAXLEN, "count relations");
 	worker.bgw_restart_time = BGW_NEVER_RESTART;
 	worker.bgw_main_arg = (Datum) 0;

hello_notify/hello_notify.c

@@ -32,6 +32,7 @@
 PG_MODULE_MAGIC;
 void _PG_init(void);
+void hello_notify_main(Datum main_arg);
 /* Worker name */
 static const char *hello_notify_name = "hello_notify";
@@ -111,7 +112,7 @@ hello_notify_build_query(StringInfoData *buf)
  *
  * Main loop processing notify requests.
  */
-static void
+void
 hello_notify_main(Datum main_arg)
 {
 	StringInfoData buf;
@@ -256,11 +257,12 @@ _PG_init(void)
 	/* Register this worker */
 	MemSet(&worker, 0, sizeof(BackgroundWorker));
+	snprintf(worker.bgw_library_name, BGW_MAXLEN, "hello_notify");
+	snprintf(worker.bgw_function_name, BGW_MAXLEN, "hello_notify_main");
 	snprintf(worker.bgw_name, BGW_MAXLEN, "%s", hello_notify_name);
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_RecoveryFinished;
-	worker.bgw_main = hello_notify_main;
 	worker.bgw_restart_time = 10;
 	worker.bgw_main_arg = (Datum) 0;
 #if PG_VERSION_NUM >= 90400

hello_signal/hello_signal.c

@@ -25,6 +25,7 @@ PG_MODULE_MAGIC;
 /* Entry point of library loading */
 void _PG_init(void);
+void hello_main(Datum main_arg);
 /* SIGTERM handling */
 static volatile sig_atomic_t got_sigterm = false;
@@ -54,7 +55,7 @@ hello_sighup(SIGNAL_ARGS)
 	errno = save_errno;
 }
-static void
+void
 hello_main(Datum main_arg)
 {
 	/*
@@ -116,7 +117,8 @@ _PG_init(void)
 	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = 0;
 	worker.bgw_start_time = BgWorkerStart_PostmasterStart;
-	worker.bgw_main = hello_main;
+	snprintf(worker.bgw_library_name, BGW_MAXLEN, "hello_signal");
+	snprintf(worker.bgw_function_name, BGW_MAXLEN, "hello_main");
 	snprintf(worker.bgw_name, BGW_MAXLEN, "%s", worker_name);
 	/* Wait 10 seconds for restart before crash */
 	worker.bgw_restart_time = 10;

hello_world/hello_world.c

@@ -25,6 +25,8 @@ PG_MODULE_MAGIC;
 /* Entry point of library loading */
 void _PG_init(void);
+/* Main loop of process */
+void hello_main(Datum main_arg)
 /* Signal handling */
 static volatile sig_atomic_t got_sigterm = false;
@@ -49,7 +51,7 @@ hello_sigterm(SIGNAL_ARGS)
  *
  * Main loop processing.
  */
-static void
+void
 hello_main(Datum main_arg)
 {
 	/* Set up the sigterm signal before unblocking them */
@@ -91,12 +93,8 @@ _PG_init(void)
 	MemSet(&worker, 0, sizeof(BackgroundWorker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
 	worker.bgw_start_time = BgWorkerStart_RecoveryFinished;
-
-	/*
-	 * Function to call when starting bgworker, in this case library is
-	 * already loaded.
-	 */
-	worker.bgw_main = hello_main;
+	snprintf(worker.bgw_library_name, BGW_MAXLEN, "hello_world");
+	snprintf(worker.bgw_function_name, BGW_MAXLEN, "hello_main");
 	snprintf(worker.bgw_name, BGW_MAXLEN, "hello world");
 	worker.bgw_restart_time = BGW_NEVER_RESTART;
 	worker.bgw_main_arg = (Datum) 0;

kill_idle/kill_idle.c

@@ -31,6 +31,7 @@ PG_MODULE_MAGIC;
 /* Entry point of library loading */
 void _PG_init(void);
+void kill_idle_main(Datum main_arg);
 /* Signal handling */
 static volatile sig_atomic_t got_sigterm = false;
@@ -73,7 +74,7 @@ kill_idle_build_query(StringInfoData *buf)
 					 kill_max_idle_time);
 }
-static void
+void
 kill_idle_main(Datum main_arg)
 {
 	StringInfoData buf;
@@ -229,7 +230,8 @@ _PG_init(void)
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
-	worker.bgw_main = kill_idle_main;
+	snprintf(worker.bgw_library_name, BGW_MAXLEN, "kill_idle");
+	snprintf(worker.bgw_function_name, BGW_MAXLEN, "kill_idle_main");
 	snprintf(worker.bgw_name, BGW_MAXLEN, "%s", worker_name);
 	/* Wait 10 seconds for restart before crash */
 	worker.bgw_restart_time = 10;

receiver_raw/receiver_raw.c

@@ -34,6 +34,7 @@ PG_MODULE_MAGIC;
 /* Entry point of library loading */
 void _PG_init(void);
+void receiver_raw_main(Datum main_arg);
 /* Signal handling */
 static volatile sig_atomic_t got_sigterm = false;
@@ -198,7 +199,7 @@ feTimestampDifference(int64 start_time, int64 stop_time,
 	}
 }
-static void
+void
 receiver_raw_main(Datum main_arg)
 {
 	/* Variables for replication connection */
@@ -583,7 +584,8 @@ _PG_init(void)
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS |
 		BGWORKER_BACKEND_DATABASE_CONNECTION;
 	worker.bgw_start_time = BgWorkerStart_ConsistentState;
-	worker.bgw_main = receiver_raw_main;
+    snprintf(worker.bgw_library_name, BGW_MAXLEN, "receiver_raw");
+	snprintf(worker.bgw_function_name, BGW_MAXLEN, "receiver_raw_main");
 	snprintf(worker.bgw_name, BGW_MAXLEN, "%s", worker_name);
 	/* Wait 10 seconds for restart before crash */
 	worker.bgw_restart_time = 10;