Add missing SYSTEMQUOTEs

Some popen() calls were missing SYSTEMQUOTEs, which caused initdb and
pg_upgrade to fail on Windows, if the installation path contained both
spaces and @ signs.

Patch by Nikhil Deshpande. Backpatch to all supported versions.

src/bin/initdb/initdb.c

@@ -1369,7 +1369,7 @@ bootstrap_template1(char *short_version)
 	unsetenv("PGCLIENTENCODING");
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" --boot -x1 %s %s",
+			 SYSTEMQUOTE "\"%s\" --boot -x1 %s %s" SYSTEMQUOTE,
 			 backend_exec, boot_options, talkargs);
 
 	PG_CMD_OPEN;
@@ -1422,7 +1422,7 @@ setup_auth(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1502,7 +1502,7 @@ get_set_pwd(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1610,7 +1610,7 @@ setup_depend(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1643,7 +1643,7 @@ setup_sysviews(void)
 	 * We use -j here to avoid backslashing stuff in system_views.sql
 	 */
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s -j template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s -j template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1674,7 +1674,7 @@ setup_description(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1726,7 +1726,7 @@ setup_conversion(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1764,7 +1764,7 @@ setup_dictionary(void)
 	 * We use -j here to avoid backslashing stuff
 	 */
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s -j template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s -j template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1814,7 +1814,7 @@ setup_privileges(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1877,7 +1877,7 @@ setup_schema(void)
 	 * We use -j here to avoid backslashing stuff in information_schema.sql
 	 */
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s -j template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s -j template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1894,7 +1894,7 @@ setup_schema(void)
 	PG_CMD_CLOSE;
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1928,7 +1928,7 @@ vacuum_db(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -1982,7 +1982,7 @@ make_template0(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);
 
@@ -2013,7 +2013,7 @@ make_postgres(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s template1 >%s",
+			 SYSTEMQUOTE "\"%s\" %s template1 >%s" SYSTEMQUOTE,
 			 backend_exec, backend_options,
 			 DEVNULL);