From 5a8b48e068859c7c720c6c109835ebbfad45633e Mon Sep 17 00:00:00 2001 From: Christopher Jeffrey Date: Wed, 6 Jul 2016 21:57:39 -0700 Subject: [PATCH 1/3] buffer: optimize hex_decode. --- benchmark/buffers/buffer-hex.js | 27 ++++++++++++++++++++++++ src/string_bytes.cc | 37 +++++++++++++++++++++------------ 2 files changed, 51 insertions(+), 13 deletions(-) create mode 100644 benchmark/buffers/buffer-hex.js diff --git a/benchmark/buffers/buffer-hex.js b/benchmark/buffers/buffer-hex.js new file mode 100644 index 00000000000000..def767050fb861 --- /dev/null +++ b/benchmark/buffers/buffer-hex.js @@ -0,0 +1,27 @@ +'use strict'; + +const common = require('../common.js'); + +const bench = common.createBenchmark(main, { + len: [0, 1, 64, 1024], + n: [1e7] +}); + +function main(conf) { + const len = conf.len | 0; + const n = conf.n | 0; + const buf = Buffer.alloc(len); + var i, b; + + for (i = 0; i < buf.length; i++) + buf[i] = i & 0xff; + + const hex = buf.toString('hex'); + + bench.start(); + + for (i = 0; i < n; i += 1) + b = Buffer.from(hex, 'hex'); + + bench.end(n); +} diff --git a/src/string_bytes.cc b/src/string_bytes.cc index 6f15ad48848ed5..c216c5db62bc98 100644 --- a/src/string_bytes.cc +++ b/src/string_bytes.cc @@ -143,16 +143,27 @@ const int8_t unbase64_table[256] = }; -template -unsigned hex2bin(TypeName c) { - if (c >= '0' && c <= '9') - return c - '0'; - if (c >= 'A' && c <= 'F') - return 10 + (c - 'A'); - if (c >= 'a' && c <= 'f') - return 10 + (c - 'a'); - return static_cast(-1); -} +const int8_t unhex_table[256] = + { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, + -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 + }; + +#define unhex(x) \ + static_cast(unhex_table[static_cast(x)]) template @@ -162,11 +173,11 @@ size_t hex_decode(char* buf, const size_t srcLen) { size_t i; for (i = 0; i < len && i * 2 + 1 < srcLen; ++i) { - unsigned a = hex2bin(src[i * 2 + 0]); - unsigned b = hex2bin(src[i * 2 + 1]); + unsigned a = unhex(src[i * 2 + 0]); + unsigned b = unhex(src[i * 2 + 1]); if (!~a || !~b) return i; - buf[i] = a * 16 + b; + buf[i] = (a << 4) | b; } return i; From ae2126747fb79aa879fdcecc1aa12aeca579429b Mon Sep 17 00:00:00 2001 From: Christopher Jeffrey Date: Thu, 7 Jul 2016 18:28:26 -0700 Subject: [PATCH 2/3] buffer: fix hex parsing and add bad hex string test. --- src/string_bytes.cc | 4 +-- test/parallel/test-buffer-badhex.js | 44 +++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+), 2 deletions(-) create mode 100644 test/parallel/test-buffer-badhex.js diff --git a/src/string_bytes.cc b/src/string_bytes.cc index c216c5db62bc98..668a3b1efe2875 100644 --- a/src/string_bytes.cc +++ b/src/string_bytes.cc @@ -143,7 +143,7 @@ const int8_t unbase64_table[256] = }; -const int8_t unhex_table[256] = +static const int8_t unhex_table[256] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, @@ -163,7 +163,7 @@ const int8_t unhex_table[256] = }; #define unhex(x) \ - static_cast(unhex_table[static_cast(x)]) + static_cast(unhex_table[static_cast(x)]) template diff --git a/test/parallel/test-buffer-badhex.js b/test/parallel/test-buffer-badhex.js new file mode 100644 index 00000000000000..2c37936ae0fd63 --- /dev/null +++ b/test/parallel/test-buffer-badhex.js @@ -0,0 +1,44 @@ +'use strict'; +var common = require('../common'); +var assert = require('assert'); + +var Buffer = require('buffer').Buffer; + +// Test hex strings and bad hex strings +{ + const buf1 = Buffer.alloc(4); + assert.equal(buf1.length, 4); + assert.deepStrictEqual(buf1, new Buffer([0, 0, 0, 0])); + assert.equal(buf1.write('abcdxx', 0, 'hex'), 2); + assert.deepStrictEqual(buf1, new Buffer([0xab, 0xcd, 0x00, 0x00])); + assert.equal(buf1.toString('hex'), 'abcd0000'); + assert.equal(buf1.write('abcdef01', 0, 'hex'), 4); + assert.deepStrictEqual(buf1, new Buffer([0xab, 0xcd, 0xef, 0x01])); + assert.equal(buf1.toString('hex'), 'abcdef01'); + + const buf2 = Buffer.from(buf1.toString('hex'), 'hex'); + assert.equal(buf1.toString('hex'), buf2.toString('hex')); + + const buf3 = Buffer.alloc(5); + assert.equal(buf3.write('abcdxx', 1, 'hex'), 2); + assert.equal(buf3.toString('hex'), '00abcd0000'); + + const buf4 = Buffer.alloc(4); + assert.deepStrictEqual(buf4, new Buffer([0, 0, 0, 0])); + assert.equal(buf4.write('xxabcd', 0, 'hex'), 0); + assert.deepStrictEqual(buf4, new Buffer([0, 0, 0, 0])); + assert.equal(buf4.write('xxab', 1, 'hex'), 0); + assert.deepStrictEqual(buf4, new Buffer([0, 0, 0, 0])); + assert.equal(buf4.write('cdxxab', 0, 'hex'), 1); + assert.deepStrictEqual(buf4, new Buffer([0xcd, 0, 0, 0])); + + const buf5 = Buffer.alloc(256); + for (let i = 0; i < 256; i++) + buf5[i] = i; + + const hex = buf5.toString('hex'); + assert.deepStrictEqual(Buffer.from(hex, 'hex'), buf5); + + const badHex = hex.slice(0, 256) + 'xx' + hex.slice(256, 510); + assert.deepStrictEqual(Buffer.from(badHex, 'hex'), buf5.slice(0, 128)); +} From 1627283660ccb8a06961a0847371be9a5f8578df Mon Sep 17 00:00:00 2001 From: Christopher Jeffrey Date: Fri, 8 Jul 2016 12:27:46 -0700 Subject: [PATCH 3/3] buffer: lint for hex parsing optimization. --- benchmark/buffers/buffer-hex.js | 7 +++---- test/parallel/test-buffer-badhex.js | 29 ++++++++++++++--------------- 2 files changed, 17 insertions(+), 19 deletions(-) diff --git a/benchmark/buffers/buffer-hex.js b/benchmark/buffers/buffer-hex.js index def767050fb861..d05bb832b3068c 100644 --- a/benchmark/buffers/buffer-hex.js +++ b/benchmark/buffers/buffer-hex.js @@ -11,17 +11,16 @@ function main(conf) { const len = conf.len | 0; const n = conf.n | 0; const buf = Buffer.alloc(len); - var i, b; - for (i = 0; i < buf.length; i++) + for (let i = 0; i < buf.length; i++) buf[i] = i & 0xff; const hex = buf.toString('hex'); bench.start(); - for (i = 0; i < n; i += 1) - b = Buffer.from(hex, 'hex'); + for (let i = 0; i < n; i += 1) + Buffer.from(hex, 'hex'); bench.end(n); } diff --git a/test/parallel/test-buffer-badhex.js b/test/parallel/test-buffer-badhex.js index 2c37936ae0fd63..3611ba3a09cdae 100644 --- a/test/parallel/test-buffer-badhex.js +++ b/test/parallel/test-buffer-badhex.js @@ -1,35 +1,34 @@ 'use strict'; -var common = require('../common'); -var assert = require('assert'); - -var Buffer = require('buffer').Buffer; +require('../common'); +const assert = require('assert'); +const Buffer = require('buffer').Buffer; // Test hex strings and bad hex strings { const buf1 = Buffer.alloc(4); - assert.equal(buf1.length, 4); + assert.strictEqual(buf1.length, 4); assert.deepStrictEqual(buf1, new Buffer([0, 0, 0, 0])); - assert.equal(buf1.write('abcdxx', 0, 'hex'), 2); + assert.strictEqual(buf1.write('abcdxx', 0, 'hex'), 2); assert.deepStrictEqual(buf1, new Buffer([0xab, 0xcd, 0x00, 0x00])); - assert.equal(buf1.toString('hex'), 'abcd0000'); - assert.equal(buf1.write('abcdef01', 0, 'hex'), 4); + assert.strictEqual(buf1.toString('hex'), 'abcd0000'); + assert.strictEqual(buf1.write('abcdef01', 0, 'hex'), 4); assert.deepStrictEqual(buf1, new Buffer([0xab, 0xcd, 0xef, 0x01])); - assert.equal(buf1.toString('hex'), 'abcdef01'); + assert.strictEqual(buf1.toString('hex'), 'abcdef01'); const buf2 = Buffer.from(buf1.toString('hex'), 'hex'); - assert.equal(buf1.toString('hex'), buf2.toString('hex')); + assert.strictEqual(buf1.toString('hex'), buf2.toString('hex')); const buf3 = Buffer.alloc(5); - assert.equal(buf3.write('abcdxx', 1, 'hex'), 2); - assert.equal(buf3.toString('hex'), '00abcd0000'); + assert.strictEqual(buf3.write('abcdxx', 1, 'hex'), 2); + assert.strictEqual(buf3.toString('hex'), '00abcd0000'); const buf4 = Buffer.alloc(4); assert.deepStrictEqual(buf4, new Buffer([0, 0, 0, 0])); - assert.equal(buf4.write('xxabcd', 0, 'hex'), 0); + assert.strictEqual(buf4.write('xxabcd', 0, 'hex'), 0); assert.deepStrictEqual(buf4, new Buffer([0, 0, 0, 0])); - assert.equal(buf4.write('xxab', 1, 'hex'), 0); + assert.strictEqual(buf4.write('xxab', 1, 'hex'), 0); assert.deepStrictEqual(buf4, new Buffer([0, 0, 0, 0])); - assert.equal(buf4.write('cdxxab', 0, 'hex'), 1); + assert.strictEqual(buf4.write('cdxxab', 0, 'hex'), 1); assert.deepStrictEqual(buf4, new Buffer([0xcd, 0, 0, 0])); const buf5 = Buffer.alloc(256);