From cfd104582220d578ab1b78a5991065d038e1f931 Mon Sep 17 00:00:00 2001
From: Sara Golemon <pollita@php.net>
Date: Thu, 16 May 2013 14:37:36 -0700
Subject: [PATCH] Add optional second arg to unserialize()

Returns the number of bytes consumed by reference for
streaming unserialization.

Actual unserialization behavior is not modified at all.

The need for this came up while trying to parse SplDoublyLinkedList's
serialization format which uses a non-standard stream of serialized values.
---
 ext/standard/basic_functions.c                |  1 +
 .../serialize/serialization_error_001.phpt    |  6 ++---
 .../tests/serialize/unserialize_consumed.phpt | 27 +++++++++++++++++++
 ext/standard/var.c                            | 10 +++++--
 4 files changed, 39 insertions(+), 5 deletions(-)
 create mode 100644 ext/standard/tests/serialize/unserialize_consumed.phpt

diff --git a/ext/standard/basic_functions.c b/ext/standard/basic_functions.c
index 9c91404eff..1379117745 100644
--- a/ext/standard/basic_functions.c
+++ b/ext/standard/basic_functions.c
@@ -2679,6 +2679,7 @@ ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_INFO(arginfo_unserialize, 0)
 	ZEND_ARG_INFO(0, variable_representation)
+	ZEND_ARG_INFO(1, consumed)
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_INFO_EX(arginfo_memory_get_usage, 0, 0, 0)
diff --git a/ext/standard/tests/serialize/serialization_error_001.phpt b/ext/standard/tests/serialize/serialization_error_001.phpt
index da6f50cc02..c6c17512f3 100644
--- a/ext/standard/tests/serialize/serialization_error_001.phpt
+++ b/ext/standard/tests/serialize/serialization_error_001.phpt
@@ -21,7 +21,7 @@ var_dump( unserialize() );
 
 //Test serialize with one more than the expected number of arguments
 var_dump( serialize(1,2) );
-var_dump( unserialize(1,2) );
+var_dump( unserialize(1,$x,2) );
 
 echo "Done";
 ?>
@@ -31,12 +31,12 @@ echo "Done";
 Warning: serialize() expects exactly 1 parameter, 0 given in %s on line 16
 NULL
 
-Warning: unserialize() expects exactly 1 parameter, 0 given in %s on line 17
+Warning: unserialize() expects at least 1 parameter, 0 given in %s on line 17
 bool(false)
 
 Warning: serialize() expects exactly 1 parameter, 2 given in %s on line 20
 NULL
 
-Warning: unserialize() expects exactly 1 parameter, 2 given in %s on line 21
+Warning: unserialize() expects at most 2 parameters, 3 given in %s on line 21
 bool(false)
 Done
diff --git a/ext/standard/tests/serialize/unserialize_consumed.phpt b/ext/standard/tests/serialize/unserialize_consumed.phpt
new file mode 100644
index 0000000000..6cc11e273f
--- /dev/null
+++ b/ext/standard/tests/serialize/unserialize_consumed.phpt
@@ -0,0 +1,27 @@
+--TEST--
+Unserialization of partial strings
+--FILE--
+<?php
+$data = [123,4.56,true];
+$ser = serialize($data);
+$serlen = strlen($ser);
+
+$unser = unserialize($ser, $consumed);
+echo "Consume full string: ";
+var_dump($serlen == $consumed);
+echo "Return original data: ";
+var_dump($unser === $data);
+
+$ser .= "junk\x01data";
+$unser = unserialize($ser, $consumed);
+echo "Consume full string(junk): ";
+var_dump($serlen == $consumed);
+echo "Return original data(junk): ";
+var_dump($unser === $data);
+
+--EXPECT--
+Consume full string: bool(true)
+Return original data: bool(true)
+Consume full string(junk): bool(true)
+Return original data(junk): bool(true)
+
diff --git a/ext/standard/var.c b/ext/standard/var.c
index f76a14cfa6..4acc6f57b7 100644
--- a/ext/standard/var.c
+++ b/ext/standard/var.c
@@ -945,7 +945,7 @@ PHP_FUNCTION(serialize)
 }
 /* }}} */
 
-/* {{{ proto mixed unserialize(string variable_representation)
+/* {{{ proto mixed unserialize(string variable_representation[, int &consumed])
    Takes a string representation of variable and recreates it */
 PHP_FUNCTION(unserialize)
 {
@@ -953,8 +953,9 @@ PHP_FUNCTION(unserialize)
 	int buf_len;
 	const unsigned char *p;
 	php_unserialize_data_t var_hash;
+	zval *consumed = NULL;
 
-	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &buf, &buf_len) == FAILURE) {
+	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|z", &buf, &buf_len, &consumed) == FAILURE) {
 		RETURN_FALSE;
 	}
 
@@ -973,6 +974,11 @@ PHP_FUNCTION(unserialize)
 		RETURN_FALSE;
 	}
 	PHP_VAR_UNSERIALIZE_DESTROY(var_hash);
+
+	if (consumed) {
+		zval_dtor(consumed);
+		ZVAL_LONG(consumed, ((char*)p) - buf);
+	}
 }
 /* }}} */
 
-- 
2.40.0