com php-src: Improve fix for bug #73807: main/php_variables .c

Commit:    bbfa1b64192fe3ccd2898e6e1f997387b4f210d1
Author:    Nikita Popov <[email protected]>         Sat, 25 Feb 2017 12:55:14 +0100
Parents:   eac8166bd468a3c7c00b5163f6f86804911b660d
Branches:  PHP-7.0 PHP-7.1 master

Link:       http://git.php.net/?p=php-src.git;a=commitdiff;h=bbfa1b64192fe3ccd2898e6e1f997387b4f210d1

Log:
Improve fix for bug #73807

At least on some architectures memmove() on FreeBSD does not
short-curcuit if src==dst. Check for it explicitly to avoid
quadratic copying.

Bugs:
https://bugs.php.net/73807

Changed paths:
  M  main/php_variables.c


Diff:
diff --git a/main/php_variables.c b/main/php_variables.c
index aa6e426..d3cfb7f 100644
--- a/main/php_variables.c
+++ b/main/php_variables.c
@@ -311,7 +311,7 @@ static inline int add_post_vars(zval *arr, post_var_data_t *vars, zend_bool eof)
 		}
 	}
 
-	if (!eof) {
+	if (!eof && ZSTR_VAL(vars->str.s) != vars->ptr) {
 		memmove(ZSTR_VAL(vars->str.s), vars->ptr, ZSTR_LEN(vars->str.s) = vars->end - vars->ptr);
 	}
 	return SUCCESS;