http: optimize checkInvalidHeaderChar()

This commit optimizes checkInvalidHeaderChar() by unrolling the
character checking loop a bit.

Additionally, some changes to the benchmark runner are needed in
order for the included benchmark to be run correctly. Specifically,
the regexp used to parse `key=value` parameters contained a greedy
quantifier that was causing the `key` to match part of the `value`
if `value` contained an equals sign.

PR-URL: https://github.com/nodejs/node/pull/6570
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>

1 files changed, 42 insertions, 0 deletions

diff --git a/benchmark/http/check_invalid_header_char.js b/benchmark/http/check_invalid_header_char.js
new file mode 100644
index 0000000000..bef44e6316
--- /dev/null
+++ b/benchmark/http/check_invalid_header_char.js
@@ -0,0 +1,42 @@
+'use strict';
+
+const common = require('../common.js');
+const _checkInvalidHeaderChar = require('_http_common')._checkInvalidHeaderChar;
+
+const bench = common.createBenchmark(main, {
+  key: [
+    // Valid
+    '',
+    '1',
+    '\t\t\t\t\t\t\t\t\t\tFoo bar baz',
+    'keep-alive',
+    'close',
+    'gzip',
+    '20091',
+    'private',
+    'text/html; charset=utf-8',
+    'text/plain',
+    'Sat, 07 May 2016 16:54:48 GMT',
+    'SAMEORIGIN',
+    'en-US',
+
+    // Invalid
+    'Here is a value that is really a folded header value\r\n  this should be \
+     supported, but it is not currently',
+    '中文呢', // unicode
+    'foo\nbar',
+    '\x7F'
+  ],
+  n: [5e8],
+});
+
+function main(conf) {
+  var n = +conf.n;
+  var key = conf.key;
+
+  bench.start();
+  for (var i = 0; i < n; i++) {
+    _checkInvalidHeaderChar(key);
+  }
+  bench.end(n);
+}