Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 6145)
+++ wp-includes/functions.php	(working copy)
@@ -690,8 +690,39 @@
 	return $array;
 }
 
-function wp_remote_fopen( $uri ) {
-	$timeout = 10;
+function wp_limited_curl($url, $bytes_limit = 30720, $timeout = 10) {
+	$ch = curl_init($url);
+	
+	$GLOBALS['__temp'] = array('total' => 0, 'output' => '', 'bytes_limit' => $bytes_limit);
+	
+	function read_body($ch, $string) {
+		$length = strlen($string);
+		
+		$GLOBALS['__temp']['total'] += $length;
+		$GLOBALS['__temp']['output'] .= $string;
+		
+		if ( $GLOBALS['__temp']['total'] > $GLOBALS['__temp']['bytes_limit'] ) 
+			return -1;
+		
+		return $length;
+	}
+	
+	curl_setopt($ch, CURLOPT_WRITEFUNCTION, 'read_body');        
+	curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
+	curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 1);
+	curl_setopt($ch, CURLOPT_BUFFERSIZE, 4096);
+	curl_setopt($ch, CURLOPT_RANGE, "0-$bytes_limit");
+	curl_exec($ch);
+	curl_close($ch);
+	
+	$output = $GLOBALS['__temp']['output'];
+	unset($GLOBALS['__temp']);
+	
+	return $output;
+}
+
+function wp_remote_fopen( $uri, $bytes_limit = 102400 ) { // 100 KB
+	$timeout = 10; 
 	$parsed_url = @parse_url($uri);
 
 	if ( !$parsed_url || !is_array($parsed_url) )
@@ -702,24 +733,21 @@
 
 	if ( ini_get('allow_url_fopen') ) {
 		$fp = @fopen( $uri, 'r' );
-		if ( !$fp )
+		if ( !is_resource($fp) )
 			return false;
 
-		//stream_set_timeout($fp, $timeout); // Requires php 4.3
+		if ( function_exists('stream_set_timeout') )
+			stream_set_timeout($fp, $timeout); // Requires php 4.3
 		$linea = '';
-		while( $remote_read = fread($fp, 4096) )
+		$bytes = 0;
+		while( ( $remote_read = fread($fp, 4096) ) && $bytes < $bytes_limit ) {
+			$bytes = $bytes + 4096;
 			$linea .= $remote_read;
+		}
 		fclose($fp);
 		return $linea;
 	} else if ( function_exists('curl_init') ) {
-		$handle = curl_init();
-		curl_setopt ($handle, CURLOPT_URL, $uri);
-		curl_setopt ($handle, CURLOPT_CONNECTTIMEOUT, 1);
-		curl_setopt ($handle, CURLOPT_RETURNTRANSFER, 1);
-		curl_setopt ($handle, CURLOPT_TIMEOUT, $timeout);
-		$buffer = curl_exec($handle);
-		curl_close($handle);
-		return $buffer;
+		return wp_limited_curl($uri, $bytes_limit, $timeout);
 	} else {
 		return false;
 	}