Merge pull request #20 from lajonat/master

Encode int64 numbers
mcollina · May 6, 2015 · 161d7c4 · 161d7c4
2 parents 2d49f07 + 4d3c647
commit 161d7c4
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Showing 3 changed files with 16 additions and 6 deletions.
diff --git a/lib/decoder.js b/lib/decoder.js
@@ -114,8 +114,9 @@ module.exports = function buildDecode(decodingTypes) {
 
     var first = buf.readUInt8(offset)
       , length
-      , result
+      , result = 0
       , type
+	  , bytePos
 
     if (!hasMinBufferSize(first, bufLength)) {
       return null
@@ -142,7 +143,10 @@ module.exports = function buildDecode(decodingTypes) {
         return buildDecodeResult(result, 5)
       case 0xcf:
         // 8-bytes BE unsigned int
-        result = buf.readUInt32BE(offset + 5) * 0xffffffff + buf.readUInt32BE(offset + 1)
+        // Read long byte by byte, big-endian
+        for (bytePos = 7; bytePos >= 0; bytePos--) {
+          result += (buf.readUInt8(offset + bytePos + 1) * Math.pow(2 , (8 *(7-bytePos))));
+        }
         return buildDecodeResult(result, 9)
       case 0xd0:
         // 1-byte signed int

diff --git a/lib/encoder.js b/lib/encoder.js
@@ -219,9 +219,11 @@ module.exports = function buildEncode(encodingTypes) {
 }
 
 function write64BitUint(buf, obj) {
-  var big = Math.floor(obj / 0xffffffff)
-  buf.writeUInt32BE(big, 5)
-  buf.writeUInt32BE(obj - big * 0xffffffff, 1)
+   // Write long byte by byte, in big-endian order
+  for (var currByte = 7; currByte >= 0; currByte--) {
+    buf[currByte + 1] = (obj & 0xff);
+    obj = obj / 256;
+  }
 }
 
 function isFloat(n) {

diff --git a/test/64-bits-unsigned-integers.js b/test/64-bits-unsigned-integers.js
@@ -18,7 +18,11 @@ test('encoding/decoding 64-bits big-endian unsigned integers', function(t) {
       var buf = encoder.encode(num)
       t.equal(buf.length, 9, 'must have 9 bytes')
       t.equal(buf[0], 0xcf, 'must have the proper header')
-      t.equal(buf.readUInt32BE(5) * base + buf.readUInt32BE(1), num, 'must decode correctly');
+      var result = 0; 
+      for (var k = 7; k >= 0; k--) {
+           result += (buf.readUInt8(k + 1) * Math.pow(2 , (8 *(7-k))));
+       }
+      t.equal(result, num, 'must decode correctly');
       t.end()
     })