Fix writing truncated packets starting with large string/buffer

fixes #1438

Author: dougwilson

Changes.md

@@ -4,6 +4,10 @@ This file is a manually maintained list of changes for each release. Feel free
 to add your changes here when sending pull requests. Also send corrections if
 you spot any mistakes.
 
+## HEAD
+
+* Fix writing truncated packets starting with large string/buffer #1438
+
 ## v2.11.0 (2016-06-06)
 
 * Add `POOL_CLOSED` code to "Pool is closed." error

lib/protocol/PacketWriter.js

@@ -188,7 +188,7 @@ PacketWriter.prototype.writeLengthCodedString = function(value) {
 
 PacketWriter.prototype._allocate = function _allocate(bytes) {
   if (!this._buffer) {
-    this._buffer = new Buffer(BUFFER_ALLOC_SIZE);
+    this._buffer = new Buffer(Math.max(BUFFER_ALLOC_SIZE, bytes));
     this._offset = 0;
     return;
   }

test/fixtures/data.csv

@@ -2,3 +2,4 @@
 2,This is a test
 3,For loading data from a file
 4,中文内容
+5,this is a long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long string

test/integration/connection/test-load-data-infile.js

@@ -14,7 +14,7 @@ common.getTestConnection(function (err, connection) {
   connection.query([
     'CREATE TEMPORARY TABLE ?? (',
     '`id` int(11) unsigned NOT NULL AUTO_INCREMENT,',
-    '`title` varchar(255),',
+    '`title` varchar(400),',
     'PRIMARY KEY (`id`)',
     ') ENGINE=InnoDB DEFAULT CHARSET=utf8'
   ].join('\n'), [table], assert.ifError);
@@ -25,16 +25,19 @@ common.getTestConnection(function (err, connection) {
 
   connection.query(sql, [path, table, ','], function (err, result) {
     assert.ifError(err);
-    assert.equal(result.affectedRows, 4);
+    assert.equal(result.affectedRows, 5);
   });
 
   connection.query('SELECT * FROM ??', [table], function (err, rows) {
     assert.ifError(err);
-    assert.equal(rows.length, 4);
+    assert.equal(rows.length, 5);
     assert.equal(rows[0].id, 1);
     assert.equal(rows[0].title, 'Hello World');
     assert.equal(rows[3].id, 4);
     assert.equal(rows[3].title, '中文内容');
+    assert.equal(rows[4].id, 5);
+    assert.equal(rows[4].title.length, 321);
+    assert.equal(rows[4].title, 'this is a long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long string');
   });
 
   connection.query(sql, [badPath, table, ','], function (err) {

test/integration/connection/test-multiple-statements-load-data-infile.js

@@ -13,7 +13,7 @@ common.getTestConnection({multipleStatements: true}, function (err, connection)
   connection.query([
     'CREATE TEMPORARY TABLE ?? (',
     '`id` int(11) unsigned NOT NULL AUTO_INCREMENT,',
-    '`title` varchar(255),',
+    '`title` varchar(400),',
     'PRIMARY KEY (`id`)',
     ') ENGINE=InnoDB DEFAULT CHARSET=utf8'
   ].join('\n'), [table], assert.ifError);
@@ -29,17 +29,20 @@ common.getTestConnection({multipleStatements: true}, function (err, connection)
   connection.query(sql, function (err, results) {
     assert.ifError(err);
     assert.equal(results.length, 2);
-    assert.equal(results[0].affectedRows, 4);
+    assert.equal(results[0].affectedRows, 5);
     assert.equal(results[1].affectedRows, 0);
   });
 
   connection.query('SELECT * FROM ??', [table], function (err, rows) {
     assert.ifError(err);
-    assert.equal(rows.length, 4);
+    assert.equal(rows.length, 5);
     assert.equal(rows[0].id, 1);
     assert.equal(rows[0].title, 'Hello World');
     assert.equal(rows[3].id, 4);
     assert.equal(rows[3].title, '中文内容');
+    assert.equal(rows[4].id, 5);
+    assert.equal(rows[4].title.length, 321);
+    assert.equal(rows[4].title, 'this is a long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long long string');
   });
 
   connection.end(assert.ifError);