Constraint memory used in TAR export

adminer/dump.inc.php

@@ -71,7 +71,8 @@ SET sql_mode = 'NO_AUTO_VALUE_ON_ZERO';
 					$data = (DB == "" || in_array($name, (array) $_POST["data"]));
 					if ($table || $data) {
 						if ($ext == "tar") {
-							ob_start();
+							$tmp_file = new TmpFile;
+							ob_start(array($tmp_file, 'write'), 1e5);
 						}
 						$adminer->dumpTable($name, ($table ? $_POST["table_style"] : ""), (is_view($table_status) ? 2 : 0));
 						if (is_view($table_status)) {
@@ -84,7 +85,8 @@ SET sql_mode = 'NO_AUTO_VALUE_ON_ZERO';
 							echo "\nDELIMITER ;;\n$triggers\nDELIMITER ;\n";
 						}
 						if ($ext == "tar") {
-							tar_file((DB != "" ? "" : "$db/") . "$name.csv", ob_get_clean());
+							ob_end_flush();
+							tar_file((DB != "" ? "" : "$db/") . "$name.csv", $tmp_file);
 						} elseif ($is_sql) {
 							echo "\n";
 						}

adminer/include/editing.inc.php

@@ -409,13 +409,13 @@ function remove_definer($query) {
 	return preg_replace('~^([A-Z =]+) DEFINER=`' . preg_replace('~@(.*)~', '`@`(%|\\1)', logged_user()) . '`~', '\\1', $query); //! proper escaping of user
 }
 
-/** Get string to add a file in TAR
-* @param string
+/** Add a file to TAR
 * @param string
+* @param TmpFile
 * @return null prints the output
 */
-function tar_file($filename, $contents) {
-	$return = pack("a100a8a8a8a12a12", $filename, 644, 0, 0, decoct(strlen($contents)), decoct(time()));
+function tar_file($filename, $tmp_file) {
+	$return = pack("a100a8a8a8a12a12", $filename, 644, 0, 0, decoct($tmp_file->size), decoct(time()));
 	$checksum = 8*32; // space for checksum itself
 	for ($i=0; $i < strlen($return); $i++) {
 		$checksum += ord($return[$i]);
@@ -423,8 +423,8 @@ function tar_file($filename, $contents) {
 	$return .= sprintf("%06o", $checksum) . "\0 ";
 	echo $return;
 	echo str_repeat("\0", 512 - strlen($return));
-	echo $contents;
-	echo str_repeat("\0", 511 - (strlen($contents) + 511) % 512);
+	$tmp_file->send();
+	echo str_repeat("\0", 511 - ($tmp_file->size + 511) % 512);
 }
 
 /** Get INI bytes value

adminer/include/tmpfile.inc.php

@@ -0,0 +1,21 @@
+<?php
+
+class TmpFile {
+	var $handler;
+	var $size;
+	
+	function TmpFile() {
+		$this->handler = tmpfile();
+	}
+	
+	function write($contents) {
+		$this->size += strlen($contents);
+		fwrite($this->handler, $contents);
+	}
+	
+	function send() {
+		fseek($this->handler, 0);
+		fpassthru($this->handler);
+		fclose($this->handler);
+	}
+}

adminer/index.php

@@ -8,6 +8,7 @@
 */
 
 include "./include/bootstrap.inc.php";
+include "./include/tmpfile.inc.php";
 
 $enum_length = "'(?:''|[^'\\\\]|\\\\.)*+'";
 $inout = "IN|OUT|INOUT";