Adapted the code to PG 11.

Antonin Houska · Antonin Houska · commit 4cc27e9e2cf2 · 2019-11-18T22:15:46.000+01:00
diff --git a/src/Makefile b/src/Makefile
@@ -1,8 +1,8 @@
 all: walbouncer
 
-# Check for PostgrSQL 9.5/9.6
-ifeq ($(shell pg_config --version | grep -E "PostgreSQL 9.[56]|10"),)
-    $(error PostgreSQL version 9.5/9.6 required, pg_config provides $(shell pg_config --version))
+# Check for PostgrSQL 9.5 through 11
+ifeq ($(shell pg_config --version | grep -E "PostgreSQL 9.[56]|10|11"),)
+    $(error PostgreSQL version 9.5 through 11 required, pg_config provides $(shell pg_config --version))
 endif
 
 CFLAGS=-O2 -Wall -Werror -g -std=gnu99
diff --git a/src/include/parser/parser.h b/src/include/parser/parser.h
@@ -11,12 +11,14 @@ typedef enum {
 	REPL_DROP_SLOT,
 	REPL_START_PHYSICAL,
 	REPL_START_LOGICAL,
-	REPL_TIMELINE
+	REPL_TIMELINE,
+	REPL_SHOW_VAR
 } ReplCommandType;
 
 typedef struct ReplicationCommand {
 	ReplCommandType command;
 	char *slotname;
+	char *varname;
 	TimeLineID timeline;
 	XLogRecPtr startpoint;
 } ReplicationCommand;
diff --git a/src/include/wbmasterconn.h b/src/include/wbmasterconn.h
@@ -51,6 +51,7 @@ bool WbMcIdentifySystem(MasterConn* master,
 		char** primary_sysid, char** primary_tli, char** primary_xpos);
 bool WbMcGetTimelineHistory(MasterConn* master, TimeLineID timeline,
 		TimelineHistory *history);
+char *WbMcShowVariable(MasterConn* master, char *varname);
 Oid * WbMcResolveOids(MasterConn *master, OidResolveKind kind, bool include, char** names, int n_items);
 const char *WbMcParameterStatus(MasterConn *master, char *name);
 #endif
diff --git a/src/include/wbpgtypes.h b/src/include/wbpgtypes.h
@@ -67,7 +67,7 @@ typedef struct BkpBlock
  * Each page of XLOG file has a header like this:
  */
 #define XLOG_PAGE_MAGIC_MIN 0xD087	/* in WB case it's OK to use a range of versions as we're only interested in fixing the RelFileNode location */
-#define XLOG_PAGE_MAGIC_MAX 0xD097
+#define XLOG_PAGE_MAGIC_MAX 0xD098
 
 typedef struct XLogPageHeaderData
 {
diff --git a/src/parser/repl_gram.y b/src/parser/repl_gram.y
@@ -64,6 +64,7 @@ ReplicationCommand *replication_parse_result;
 /* Keyword tokens. */
 %token K_BASE_BACKUP
 %token K_IDENTIFY_SYSTEM
+%token K_SHOW
 %token K_START_REPLICATION
 %token K_CREATE_REPLICATION_SLOT
 %token K_DROP_REPLICATION_SLOT
@@ -80,7 +81,7 @@ ReplicationCommand *replication_parse_result;
 %token K_SLOT
 
 %type <cmd>	command
-%type <cmd>	base_backup start_replication start_logical_replication create_replication_slot drop_replication_slot identify_system timeline_history
+%type <cmd>	base_backup start_replication start_logical_replication create_replication_slot drop_replication_slot identify_system timeline_history show
 //%type <list>	base_backup_opt_list
 //%type <defelt>	base_backup_opt
 %type <str>	base_backup_opt_list
@@ -94,7 +95,7 @@ ReplicationCommand *replication_parse_result;
 %type <str>	plugin_opt_elem
 %type <str>	plugin_opt_arg
 
-%type <str>		opt_slot
+%type <str>		opt_slot var_name
 
 %%
 
@@ -116,6 +117,7 @@ command:
 			| create_replication_slot
 			| drop_replication_slot
 			| timeline_history
+			| show
 			;
 
 /*
@@ -128,6 +130,28 @@ identify_system:
 				}
 			;
 
+/*
+ * SHOW setting
+ */
+show:
+			K_SHOW var_name
+				{
+					ReplicationCommand *cmd = MakeReplCommand(REPL_SHOW_VAR);
+
+					cmd->varname = $2;
+					$$ = cmd;
+				}
+
+var_name:	IDENT	{ $$ = $1; }
+			| var_name '.' IDENT
+			{ char *s1 = $1;
+			  char *s2 = $3;
+			  char *res = wballoc(strlen(s1) + strlen(s2) + 1);
+
+			  sprintf(res, "%s.%s", s1, s2);
+			  $$ = res;}
+		;
+
 /*
  * BASE_BACKUP [LABEL '<label>'] [PROGRESS] [FAST] [WAL] [NOWAIT] [MAX_RATE %d]
  */
diff --git a/src/parser/repl_scanner.l b/src/parser/repl_scanner.l
@@ -83,6 +83,7 @@ identifier		{ident_start}{ident_cont}*
 BASE_BACKUP			{ return K_BASE_BACKUP; }
 FAST			{ return K_FAST; }
 IDENTIFY_SYSTEM		{ return K_IDENTIFY_SYSTEM; }
+SHOW		{ return K_SHOW; }
 LABEL			{ return K_LABEL; }
 NOWAIT			{ return K_NOWAIT; }
 PROGRESS			{ return K_PROGRESS; }
@@ -146,9 +147,12 @@ SLOT				{ return K_SLOT; }
 				}
 
 <xd>{xdstop}	{
+					int len;
 					yyless(1);
 					BEGIN(INITIAL);
 					yylval.str = litbufdup();
+					len = strlen(yylval.str);
+					truncate_identifier(yylval.str, len, true);
 					return IDENT;
 				}
 
@@ -157,9 +161,9 @@ SLOT				{ return K_SLOT; }
 				}
 
 {identifier}	{
-					//int len = strlen(yytext);
+					int len = strlen(yytext);
 
-					yylval.str = litbufdup();//downcase_truncate_identifier(yytext, len, true);
+					yylval.str = downcase_truncate_identifier(yytext, len, true);
 					return IDENT;
 				}
 
diff --git a/src/wbclientconn.c b/src/wbclientconn.c
@@ -40,6 +40,7 @@ static void WbCCExecIdentifySystem(WbConn conn, MasterConn *master);
 static bool WbCCWaitForData(WbConn conn, MasterConn *master);
 static void WbCCExecStartPhysical(WbConn conn, MasterConn *master, ReplicationCommand *cmd);
 static void WbCCExecTimeline(WbConn conn, MasterConn *master, ReplicationCommand *cmd);
+static void WbCCExecShow(WbConn conn, MasterConn *master, ReplicationCommand *cmd);
 static void WbCCLookupFilteringOids(WbConn conn, FilterData *fl);
 //static void WbCCSendWALRecord(XfConn conn, char *data, int len, XLogRecPtr sentPtr, TimestampTz lastSend);
 //static void WbCCSendEndOfWal(XfConn conn);
@@ -527,6 +528,9 @@ WbCCExecCommand(WbConn conn, MasterConn *master, char *query_string)
 		case REPL_TIMELINE:
 			WbCCExecTimeline(conn, master, cmd);
 			break;
+		case REPL_SHOW_VAR:
+			WbCCExecShow(conn, master, cmd);
+			break;
 	}
 
 
@@ -814,6 +818,27 @@ WbCCExecTimeline(WbConn conn, MasterConn *master, ReplicationCommand *cmd)
 	wbfree(history.content);
 }
 
+static void
+WbCCExecShow(WbConn conn, MasterConn *master, ReplicationCommand *cmd)
+{
+	char	*value;
+
+	log_info("Received request for variable %s", cmd->varname);
+
+	value = WbMcShowVariable(master, cmd->varname);
+
+	{
+		ResultCol cols[1] = {
+				{ cmd->varname, TEXTOID, value, 0}
+		};
+		WbCCSendResultset(conn, 1, cols);
+	}
+
+	log_info("Sent out variable value %s", value);
+
+	wbfree(value);
+}
+
 static void
 WbCCLookupFilteringOids(WbConn conn, FilterData *fl)
 {
diff --git a/src/wbmasterconn.c b/src/wbmasterconn.c
@@ -387,6 +387,34 @@ WbMcGetTimelineHistory(MasterConn* master, TimeLineID timeline,
 	return true;
 }
 
+char *
+WbMcShowVariable(MasterConn* master, char *varname)
+{
+	PGconn *mc = master->conn;
+	char query[1024];
+	PGresult *result;
+	char	*value;
+
+	snprintf(query, 1024, "SHOW %s", varname);
+
+	result = PQexec(mc, query);
+
+	if (PQresultStatus(result) != PGRES_TUPLES_OK)
+	{
+		log_debug1("Variable returned %s", PQresStatus(PQresultStatus(result)));
+		PQclear(result);
+		error("Getting variable from master failed with: %s", PQerrorMessage(mc));
+	}
+	if (PQntuples(result) != 1)
+	{
+		error("Invalid response for SHOW command: %d tuples", PQnfields(result));
+	}
+
+	value = wbstrdup(PQgetvalue(result, 0, 0));
+    PQclear(result);
+	return value;
+}
+
 Oid *
 WbMcResolveOids(MasterConn *master, OidResolveKind kind, bool include, char** names, int n_items)
 {

Original file line number	Diff line number	Diff line change
`@@ -67,7 +67,7 @@ typedef struct BkpBlock`
`67`	`67`	`* Each page of XLOG file has a header like this:`
`68`	`68`	`*/`
`69`	`69`	`#define XLOG_PAGE_MAGIC_MIN 0xD087 /* in WB case it's OK to use a range of versions as we're only interested in fixing the RelFileNode location */`
`70`		`-#define XLOG_PAGE_MAGIC_MAX 0xD097`
	`70`	`+#define XLOG_PAGE_MAGIC_MAX 0xD098`
`71`	`71`
`72`	`72`	`typedef struct XLogPageHeaderData`
`73`	`73`	`{`