ext/pgsql: add pg_result_memory_size

Close GH-14214

Author: KentarouTakeda

NEWS

@@ -183,6 +183,8 @@ PHP                                                                        NEWS
   . Added the possibility to have no conditions for pg_select. (OmarEmaraDev)
   . Persistent connections support the PGSQL_CONNECT_FORCE_RENEW flag.
     (David Carlier)
+  . Added pg_result_memory_size to get the query result memory usage.
+    (KentarouTakeda)
 
 - Phar:
   . Fixed bug GH-12532 (PharData created from zip has incorrect timestamp).

UPGRADING

@@ -339,6 +339,7 @@ PHP 8.4 UPGRADE NOTES
     3-parameter signature with a null $row parameter instead.
   . Calling pg_field_is_null() with 2 arguments is deprecated. Use the
     3-parameter signature with a null $row parameter instead.
+  . Added pg_result_memory_size to get the visibility the memory used by a query result.
 
 - Reflection:
   . Calling ReflectionMethod::__construct() with 1 argument is deprecated.

ext/pgsql/config.m4

@@ -66,6 +66,7 @@ if test "$PHP_PGSQL" != "no"; then
   AC_CHECK_LIB(pq, pg_encoding_to_char,AC_DEFINE(HAVE_PGSQL_WITH_MULTIBYTE_SUPPORT,1,[Whether libpq is compiled with --enable-multibyte]))
   AC_CHECK_LIB(pq, lo_truncate64, AC_DEFINE(HAVE_PG_LO64,1,[PostgreSQL 9.3 or later]))
   AC_CHECK_LIB(pq, PQsetErrorContextVisibility, AC_DEFINE(HAVE_PG_CONTEXT_VISIBILITY,1,[PostgreSQL 9.6 or later]))
+  AC_CHECK_LIB(pq, PQresultMemorySize, AC_DEFINE(HAVE_PG_RESULT_MEMORY_SIZE,1,[PostgreSQL 12 or later]))
   LIBS=$old_LIBS
   LDFLAGS=$old_LDFLAGS
 

ext/pgsql/pgsql.c

@@ -2911,6 +2911,23 @@ PHP_FUNCTION(pg_set_error_context_visibility)
 }
 #endif
 
+#ifdef HAVE_PG_RESULT_MEMORY_SIZE
+PHP_FUNCTION(pg_result_memory_size)
+{
+	zval *result;
+	pgsql_result_handle *pg_result;
+
+	if (zend_parse_parameters(ZEND_NUM_ARGS(), "O", &result, pgsql_result_ce) == FAILURE) {
+		RETURN_THROWS();
+	}
+
+	pg_result = Z_PGSQL_RESULT_P(result);
+	CHECK_PGSQL_RESULT(pg_result);
+
+	RETURN_LONG(PQresultMemorySize(pg_result->result));
+}
+#endif
+
 /* {{{ Set client encoding */
 PHP_FUNCTION(pg_set_client_encoding)
 {

ext/pgsql/pgsql.stub.php

@@ -943,6 +943,10 @@ function pg_select(PgSql\Connection $connection, string $table_name, array $cond
 #ifdef HAVE_PG_CONTEXT_VISIBILITY
     function pg_set_error_context_visibility(PgSql\Connection $connection, int $visibility): int {}
 #endif
+
+#ifdef HAVE_PG_RESULT_MEMORY_SIZE
+    function pg_result_memory_size(PgSql\Result $result): int {}
+#endif
 }
 
 namespace PgSql {

ext/pgsql/pgsql_arginfo.h

@@ -0,0 +1,29 @@
+--TEST--
+pg_result_memory_size
+--EXTENSIONS--
+pgsql
+--SKIPIF--
+<?php
+include("inc/skipif.inc");
+if (!function_exists('pg_result_memory_size')) die('skip function pg_result_memory_size() does not exist');
+?>
+--FILE--
+<?php
+include('inc/config.inc');
+
+$db = pg_connect($conn_str);
+
+$result = pg_query($db, 'select 1');
+$size_1 = pg_result_memory_size($result);
+
+$result = pg_query($db, "select generate_series(1, 10000) as i, repeat('string', 100)");
+$size_2 = pg_result_memory_size($result);
+
+var_dump($size_1);
+var_dump($size_2);
+var_dump($size_1 < $size_2);
+?>
+--EXPECTF--
+int(%d)
+int(%d)
+bool(true)