Reduce variables scope

percona_pg_telemetry.c

@@ -582,14 +582,11 @@ server_uptime(void)
 static void
 write_pg_settings(void)
 {
-	SPITupleTable *tuptable;
 	int			spi_result;
 	char	   *query = "SELECT name, unit, setting FROM pg_settings where vartype != 'string'";
 	char		buf[4096] = {0};
 	size_t		buf_size = sizeof(buf);
 	FILE	   *fp;
-	int			flags;
-
 
 	/* Open file in append mode. */
 	fp = open_telemetry_file(ptss->dbtemp_filepath, "a+");
@@ -617,7 +614,8 @@ write_pg_settings(void)
 	/* Process the result */
 	if (SPI_processed > 0)
 	{
-		tuptable = SPI_tuptable;
+		int			flags;
+		SPITupleTable *tuptable = SPI_tuptable;
 
 		for (int row_count = 0; row_count < SPI_processed; row_count++)
 		{
@@ -675,7 +673,6 @@ get_database_list(void)
 	Relation	rel;
 	TableScanDesc scan;
 	HeapTuple	tup;
-	MemoryContext oldcxt;
 	ScanKeyData key;
 
 	/* Start a transaction to access pg_database */
@@ -694,6 +691,7 @@ get_database_list(void)
 
 	while (HeapTupleIsValid(tup = heap_getnext(scan, ForwardScanDirection)))
 	{
+		MemoryContext oldcxt;
 		PTDatabaseInfo *dbinfo;
 		int64		datsize;
 		Form_pg_database pgdatabase = (Form_pg_database) GETSTRUCT(tup);
@@ -736,7 +734,6 @@ get_extensions_list(PTDatabaseInfo *dbinfo, MemoryContext cxt)
 	Relation	rel;
 	TableScanDesc scan;
 	HeapTuple	tup;
-	MemoryContext oldcxt;
 
 	Assert(dbinfo);
 
@@ -749,6 +746,7 @@ get_extensions_list(PTDatabaseInfo *dbinfo, MemoryContext cxt)
 
 	while (HeapTupleIsValid(tup = heap_getnext(scan, ForwardScanDirection)))
 	{
+		MemoryContext oldcxt;
 		PTExtensionInfo *extinfo;
 		Form_pg_extension extform = (Form_pg_extension) GETSTRUCT(tup);
 
@@ -854,12 +852,6 @@ void
 percona_pg_telemetry_main(Datum main_arg)
 {
 	int			rc = 0;
-	List	   *dblist = NIL;
-	ListCell   *lc = NULL;
-	FILE	   *fp;
-	char		str[2048] = {0};
-	char		buf[4096] = {0};
-	size_t		buf_size = sizeof(buf);
 	bool		first_time = true;
 
 	/* Setup signal callbacks */
@@ -891,6 +883,11 @@ percona_pg_telemetry_main(Datum main_arg)
 	/* Should never really terminate unless... */
 	while (!sigterm_recvd && ptss->error_code == PT_SUCCESS)
 	{
+		FILE	   *fp;
+		char		buf[4096] = {0};
+		size_t		buf_size = sizeof(buf);
+		List	   *dblist = NIL;
+
 		/* Don't sleep the first time */
 		if (first_time == false)
 		{
@@ -924,7 +921,7 @@ percona_pg_telemetry_main(Datum main_arg)
 		 */
 		if (dblist == NIL && (rc & WL_TIMEOUT || first_time))
 		{
-			char		temp_buff[100];
+			char		str[2048] = {0};
 
 			/* Data collection will start now */
 			first_time = false;
@@ -956,8 +953,8 @@ percona_pg_telemetry_main(Datum main_arg)
 			write_telemetry_file(fp, buf);
 
 			/* Construct and initiate the active extensions array block. */
-			pg_snprintf(temp_buff, sizeof(temp_buff), "%d", list_length(dblist));
-			construct_json_block(buf, buf_size, "databases_count", temp_buff, PT_JSON_KEY_VALUE, &ptss->json_file_indent);
+			pg_snprintf(str, sizeof(str), "%d", list_length(dblist));
+			construct_json_block(buf, buf_size, "databases_count", str, PT_JSON_KEY_VALUE, &ptss->json_file_indent);
 			write_telemetry_file(fp, buf);
 
 			/* Let's close the file now so that processes may add their stuff. */
@@ -969,6 +966,7 @@ percona_pg_telemetry_main(Datum main_arg)
 		{
 			PTDatabaseInfo *dbinfo;
 			BgwHandleStatus status;
+			ListCell   *lc = NULL;
 
 			/* First or the next cell */
 #if PG_VERSION_NUM >= 130000

pt_json.c

@@ -24,7 +24,6 @@ static char *json_escape_str(char *str);
 char *
 json_escape_str(char *str)
 {
-	int			i;
 	int			len;
 	int			maxlen;
 	char	   *str_escaped;
@@ -40,7 +39,7 @@ json_escape_str(char *str)
 	str_escaped = (char *) palloc(maxlen);
 	s = str_escaped;
 
-	for (i = 0; i < len; i++)
+	for (int i = 0; i < len; i++)
 	{
 		/* Escape the quote and backslash characters. */
 		if (str[i] == '"' || str[i] == '\\')