From f0b14c7a69f4da44a9ebafab56e465a18920c59b Mon Sep 17 00:00:00 2001 From: James Halliday Date: Wed, 20 Mar 2013 11:58:49 -0700 Subject: [PATCH] read/write ported from old buffer into new buffer, no more old buffer code left --- index.js | 592 ++++++++++++++++++++++++++++++++++++++++++++- old_buffer.js | 650 -------------------------------------------------- 2 files changed, 590 insertions(+), 652 deletions(-) delete mode 100644 old_buffer.js diff --git a/index.js b/index.js index 2f7514e..7e61f58 100644 --- a/index.js +++ b/index.js @@ -334,8 +334,8 @@ Buffer.prototype.copy = function(target, target_start, start, end) { temp.push(this[i]); } - for (var i=targetstart; i= buffer.length) return; + + return buffer.parent[buffer.offset + offset]; +}; + +function readUInt16(buffer, offset, isBigEndian, noAssert) { + var val = 0; + + + if (!noAssert) { + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 1 < buffer.length, + 'Trying to read beyond buffer length'); + } + + if (offset >= buffer.length) return 0; + + if (isBigEndian) { + val = buffer.parent[buffer.offset + offset] << 8; + if (offset + 1 < buffer.length) { + val |= buffer.parent[buffer.offset + offset + 1]; + } + } else { + val = buffer.parent[buffer.offset + offset]; + if (offset + 1 < buffer.length) { + val |= buffer.parent[buffer.offset + offset + 1] << 8; + } + } + + return val; +} + +Buffer.prototype.readUInt16LE = function(offset, noAssert) { + return readUInt16(this, offset, false, noAssert); +}; + +Buffer.prototype.readUInt16BE = function(offset, noAssert) { + return readUInt16(this, offset, true, noAssert); +}; + +function readUInt32(buffer, offset, isBigEndian, noAssert) { + var val = 0; + + if (!noAssert) { + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 3 < buffer.length, + 'Trying to read beyond buffer length'); + } + + if (offset >= buffer.length) return 0; + + if (isBigEndian) { + if (offset + 1 < buffer.length) + val = buffer.parent[buffer.offset + offset + 1] << 16; + if (offset + 2 < buffer.length) + val |= buffer.parent[buffer.offset + offset + 2] << 8; + if (offset + 3 < buffer.length) + val |= buffer.parent[buffer.offset + offset + 3]; + val = val + (buffer.parent[buffer.offset + offset] << 24 >>> 0); + } else { + if (offset + 2 < buffer.length) + val = buffer.parent[buffer.offset + offset + 2] << 16; + if (offset + 1 < buffer.length) + val |= buffer.parent[buffer.offset + offset + 1] << 8; + val |= buffer.parent[buffer.offset + offset]; + if (offset + 3 < buffer.length) + val = val + (buffer.parent[buffer.offset + offset + 3] << 24 >>> 0); + } + + return val; +} + +Buffer.prototype.readUInt32LE = function(offset, noAssert) { + return readUInt32(this, offset, false, noAssert); +}; + +Buffer.prototype.readUInt32BE = function(offset, noAssert) { + return readUInt32(this, offset, true, noAssert); +}; + + +/* + * Signed integer types, yay team! A reminder on how two's complement actually + * works. The first bit is the signed bit, i.e. tells us whether or not the + * number should be positive or negative. If the two's complement value is + * positive, then we're done, as it's equivalent to the unsigned representation. + * + * Now if the number is positive, you're pretty much done, you can just leverage + * the unsigned translations and return those. Unfortunately, negative numbers + * aren't quite that straightforward. + * + * At first glance, one might be inclined to use the traditional formula to + * translate binary numbers between the positive and negative values in two's + * complement. (Though it doesn't quite work for the most negative value) + * Mainly: + * - invert all the bits + * - add one to the result + * + * Of course, this doesn't quite work in Javascript. Take for example the value + * of -128. This could be represented in 16 bits (big-endian) as 0xff80. But of + * course, Javascript will do the following: + * + * > ~0xff80 + * -65409 + * + * Whoh there, Javascript, that's not quite right. But wait, according to + * Javascript that's perfectly correct. When Javascript ends up seeing the + * constant 0xff80, it has no notion that it is actually a signed number. It + * assumes that we've input the unsigned value 0xff80. Thus, when it does the + * binary negation, it casts it into a signed value, (positive 0xff80). Then + * when you perform binary negation on that, it turns it into a negative number. + * + * Instead, we're going to have to use the following general formula, that works + * in a rather Javascript friendly way. I'm glad we don't support this kind of + * weird numbering scheme in the kernel. + * + * (BIT-MAX - (unsigned)val + 1) * -1 + * + * The astute observer, may think that this doesn't make sense for 8-bit numbers + * (really it isn't necessary for them). However, when you get 16-bit numbers, + * you do. Let's go back to our prior example and see how this will look: + * + * (0xffff - 0xff80 + 1) * -1 + * (0x007f + 1) * -1 + * (0x0080) * -1 + */ +Buffer.prototype.readInt8 = function(offset, noAssert) { + var buffer = this; + var neg; + + if (!noAssert) { + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset < buffer.length, + 'Trying to read beyond buffer length'); + } + + if (offset >= buffer.length) return; + + neg = buffer.parent[buffer.offset + offset] & 0x80; + if (!neg) { + return (buffer.parent[buffer.offset + offset]); + } + + return ((0xff - buffer.parent[buffer.offset + offset] + 1) * -1); +}; + +function readInt16(buffer, offset, isBigEndian, noAssert) { + var neg, val; + + if (!noAssert) { + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 1 < buffer.length, + 'Trying to read beyond buffer length'); + } + + val = readUInt16(buffer, offset, isBigEndian, noAssert); + neg = val & 0x8000; + if (!neg) { + return val; + } + + return (0xffff - val + 1) * -1; +} + +Buffer.prototype.readInt16LE = function(offset, noAssert) { + return readInt16(this, offset, false, noAssert); +}; + +Buffer.prototype.readInt16BE = function(offset, noAssert) { + return readInt16(this, offset, true, noAssert); +}; + +function readInt32(buffer, offset, isBigEndian, noAssert) { + var neg, val; + + if (!noAssert) { + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 3 < buffer.length, + 'Trying to read beyond buffer length'); + } + + val = readUInt32(buffer, offset, isBigEndian, noAssert); + neg = val & 0x80000000; + if (!neg) { + return (val); + } + + return (0xffffffff - val + 1) * -1; +} + +Buffer.prototype.readInt32LE = function(offset, noAssert) { + return readInt32(this, offset, false, noAssert); +}; + +Buffer.prototype.readInt32BE = function(offset, noAssert) { + return readInt32(this, offset, true, noAssert); +}; + +function readFloat(buffer, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset + 3 < buffer.length, + 'Trying to read beyond buffer length'); + } + + return require('./buffer_ieee754').readIEEE754(buffer, offset, isBigEndian, + 23, 4); +} + +Buffer.prototype.readFloatLE = function(offset, noAssert) { + return readFloat(this, offset, false, noAssert); +}; + +Buffer.prototype.readFloatBE = function(offset, noAssert) { + return readFloat(this, offset, true, noAssert); +}; + +function readDouble(buffer, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset + 7 < buffer.length, + 'Trying to read beyond buffer length'); + } + + return require('./buffer_ieee754').readIEEE754(buffer, offset, isBigEndian, + 52, 8); +} + +Buffer.prototype.readDoubleLE = function(offset, noAssert) { + return readDouble(this, offset, false, noAssert); +}; + +Buffer.prototype.readDoubleBE = function(offset, noAssert) { + return readDouble(this, offset, true, noAssert); +}; + + +/* + * We have to make sure that the value is a valid integer. This means that it is + * non-negative. It has no fractional component and that it does not exceed the + * maximum allowed value. + * + * value The number to check for validity + * + * max The maximum value + */ +function verifuint(value, max) { + assert.ok(typeof (value) == 'number', + 'cannot write a non-number as a number'); + + assert.ok(value >= 0, + 'specified a negative value for writing an unsigned value'); + + assert.ok(value <= max, 'value is larger than maximum value for type'); + + assert.ok(Math.floor(value) === value, 'value has a fractional component'); +} + +Buffer.prototype.writeUInt8 = function(value, offset, noAssert) { + var buffer = this; + + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset < buffer.length, + 'trying to write beyond buffer length'); + + verifuint(value, 0xff); + } + + if (offset < buffer.length) { + buffer.parent[buffer.offset + offset] = value; + } +}; + +function writeUInt16(buffer, value, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 1 < buffer.length, + 'trying to write beyond buffer length'); + + verifuint(value, 0xffff); + } + + for (var i = 0; i < Math.min(buffer.length - offset, 2); i++) { + buffer.parent[buffer.offset + offset + i] = + (value & (0xff << (8 * (isBigEndian ? 1 - i : i)))) >>> + (isBigEndian ? 1 - i : i) * 8; + } + +} + +Buffer.prototype.writeUInt16LE = function(value, offset, noAssert) { + writeUInt16(this, value, offset, false, noAssert); +}; + +Buffer.prototype.writeUInt16BE = function(value, offset, noAssert) { + writeUInt16(this, value, offset, true, noAssert); +}; + +function writeUInt32(buffer, value, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 3 < buffer.length, + 'trying to write beyond buffer length'); + + verifuint(value, 0xffffffff); + } + + for (var i = 0; i < Math.min(buffer.length - offset, 4); i++) { + buffer.parent[buffer.offset + offset + i] = + (value >>> (isBigEndian ? 3 - i : i) * 8) & 0xff; + } +} + +Buffer.prototype.writeUInt32LE = function(value, offset, noAssert) { + writeUInt32(this, value, offset, false, noAssert); +}; + +Buffer.prototype.writeUInt32BE = function(value, offset, noAssert) { + writeUInt32(this, value, offset, true, noAssert); +}; + + +/* + * We now move onto our friends in the signed number category. Unlike unsigned + * numbers, we're going to have to worry a bit more about how we put values into + * arrays. Since we are only worrying about signed 32-bit values, we're in + * slightly better shape. Unfortunately, we really can't do our favorite binary + * & in this system. It really seems to do the wrong thing. For example: + * + * > -32 & 0xff + * 224 + * + * What's happening above is really: 0xe0 & 0xff = 0xe0. However, the results of + * this aren't treated as a signed number. Ultimately a bad thing. + * + * What we're going to want to do is basically create the unsigned equivalent of + * our representation and pass that off to the wuint* functions. To do that + * we're going to do the following: + * + * - if the value is positive + * we can pass it directly off to the equivalent wuint + * - if the value is negative + * we do the following computation: + * mb + val + 1, where + * mb is the maximum unsigned value in that byte size + * val is the Javascript negative integer + * + * + * As a concrete value, take -128. In signed 16 bits this would be 0xff80. If + * you do out the computations: + * + * 0xffff - 128 + 1 + * 0xffff - 127 + * 0xff80 + * + * You can then encode this value as the signed version. This is really rather + * hacky, but it should work and get the job done which is our goal here. + */ + +/* + * A series of checks to make sure we actually have a signed 32-bit number + */ +function verifsint(value, max, min) { + assert.ok(typeof (value) == 'number', + 'cannot write a non-number as a number'); + + assert.ok(value <= max, 'value larger than maximum allowed value'); + + assert.ok(value >= min, 'value smaller than minimum allowed value'); + + assert.ok(Math.floor(value) === value, 'value has a fractional component'); +} + +function verifIEEE754(value, max, min) { + assert.ok(typeof (value) == 'number', + 'cannot write a non-number as a number'); + + assert.ok(value <= max, 'value larger than maximum allowed value'); + + assert.ok(value >= min, 'value smaller than minimum allowed value'); +} + +Buffer.prototype.writeInt8 = function(value, offset, noAssert) { + var buffer = this; + + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset < buffer.length, + 'Trying to write beyond buffer length'); + + verifsint(value, 0x7f, -0x80); + } + + if (value >= 0) { + buffer.writeUInt8(value, offset, noAssert); + } else { + buffer.writeUInt8(0xff + value + 1, offset, noAssert); + } +}; + +function writeInt16(buffer, value, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 1 < buffer.length, + 'Trying to write beyond buffer length'); + + verifsint(value, 0x7fff, -0x8000); + } + + if (value >= 0) { + writeUInt16(buffer, value, offset, isBigEndian, noAssert); + } else { + writeUInt16(buffer, 0xffff + value + 1, offset, isBigEndian, noAssert); + } +} + +Buffer.prototype.writeInt16LE = function(value, offset, noAssert) { + writeInt16(this, value, offset, false, noAssert); +}; + +Buffer.prototype.writeInt16BE = function(value, offset, noAssert) { + writeInt16(this, value, offset, true, noAssert); +}; + +function writeInt32(buffer, value, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 3 < buffer.length, + 'Trying to write beyond buffer length'); + + verifsint(value, 0x7fffffff, -0x80000000); + } + + if (value >= 0) { + writeUInt32(buffer, value, offset, isBigEndian, noAssert); + } else { + writeUInt32(buffer, 0xffffffff + value + 1, offset, isBigEndian, noAssert); + } +} + +Buffer.prototype.writeInt32LE = function(value, offset, noAssert) { + writeInt32(this, value, offset, false, noAssert); +}; + +Buffer.prototype.writeInt32BE = function(value, offset, noAssert) { + writeInt32(this, value, offset, true, noAssert); +}; + +function writeFloat(buffer, value, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 3 < buffer.length, + 'Trying to write beyond buffer length'); + + verifIEEE754(value, 3.4028234663852886e+38, -3.4028234663852886e+38); + } + + require('./buffer_ieee754').writeIEEE754(buffer, value, offset, isBigEndian, + 23, 4); +} + +Buffer.prototype.writeFloatLE = function(value, offset, noAssert) { + writeFloat(this, value, offset, false, noAssert); +}; + +Buffer.prototype.writeFloatBE = function(value, offset, noAssert) { + writeFloat(this, value, offset, true, noAssert); +}; + +function writeDouble(buffer, value, offset, isBigEndian, noAssert) { + if (!noAssert) { + assert.ok(value !== undefined && value !== null, + 'missing value'); + + assert.ok(typeof (isBigEndian) === 'boolean', + 'missing or invalid endian'); + + assert.ok(offset !== undefined && offset !== null, + 'missing offset'); + + assert.ok(offset + 7 < buffer.length, + 'Trying to write beyond buffer length'); + + verifIEEE754(value, 1.7976931348623157E+308, -1.7976931348623157E+308); + } + + require('./buffer_ieee754').writeIEEE754(buffer, value, offset, isBigEndian, + 52, 8); +} + +Buffer.prototype.writeDoubleLE = function(value, offset, noAssert) { + writeDouble(this, value, offset, false, noAssert); +}; + +Buffer.prototype.writeDoubleBE = function(value, offset, noAssert) { + writeDouble(this, value, offset, true, noAssert); +}; diff --git a/old_buffer.js b/old_buffer.js deleted file mode 100644 index 9202fba..0000000 --- a/old_buffer.js +++ /dev/null @@ -1,650 +0,0 @@ -// slice(start, end) -Buffer.prototype.slice = function(start, end) { - if (end === undefined) end = this.length; - if (end > this.length) throw new Error('oob'); - if (start > end) throw new Error('oob'); - - return new Buffer(this.parent, end - start, +start + this.offset); -}; - - -// Legacy methods for backwards compatibility. - -Buffer.prototype.utf8Slice = function(start, end) { - return this.toString('utf8', start, end); -}; - -Buffer.prototype.binarySlice = function(start, end) { - return this.toString('binary', start, end); -}; - -Buffer.prototype.asciiSlice = function(start, end) { - return this.toString('ascii', start, end); -}; - -Buffer.prototype.utf8Write = function(string, offset) { - return this.write(string, offset, 'utf8'); -}; - -Buffer.prototype.binaryWrite = function(string, offset) { - return this.write(string, offset, 'binary'); -}; - -Buffer.prototype.asciiWrite = function(string, offset) { - return this.write(string, offset, 'ascii'); -}; - -Buffer.prototype.readUInt8 = function(offset, noAssert) { - var buffer = this; - - if (!noAssert) { - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset < buffer.length, - 'Trying to read beyond buffer length'); - } - - if (offset >= buffer.length) return; - - return buffer.parent[buffer.offset + offset]; -}; - -function readUInt16(buffer, offset, isBigEndian, noAssert) { - var val = 0; - - - if (!noAssert) { - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 1 < buffer.length, - 'Trying to read beyond buffer length'); - } - - if (offset >= buffer.length) return 0; - - if (isBigEndian) { - val = buffer.parent[buffer.offset + offset] << 8; - if (offset + 1 < buffer.length) { - val |= buffer.parent[buffer.offset + offset + 1]; - } - } else { - val = buffer.parent[buffer.offset + offset]; - if (offset + 1 < buffer.length) { - val |= buffer.parent[buffer.offset + offset + 1] << 8; - } - } - - return val; -} - -Buffer.prototype.readUInt16LE = function(offset, noAssert) { - return readUInt16(this, offset, false, noAssert); -}; - -Buffer.prototype.readUInt16BE = function(offset, noAssert) { - return readUInt16(this, offset, true, noAssert); -}; - -function readUInt32(buffer, offset, isBigEndian, noAssert) { - var val = 0; - - if (!noAssert) { - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 3 < buffer.length, - 'Trying to read beyond buffer length'); - } - - if (offset >= buffer.length) return 0; - - if (isBigEndian) { - if (offset + 1 < buffer.length) - val = buffer.parent[buffer.offset + offset + 1] << 16; - if (offset + 2 < buffer.length) - val |= buffer.parent[buffer.offset + offset + 2] << 8; - if (offset + 3 < buffer.length) - val |= buffer.parent[buffer.offset + offset + 3]; - val = val + (buffer.parent[buffer.offset + offset] << 24 >>> 0); - } else { - if (offset + 2 < buffer.length) - val = buffer.parent[buffer.offset + offset + 2] << 16; - if (offset + 1 < buffer.length) - val |= buffer.parent[buffer.offset + offset + 1] << 8; - val |= buffer.parent[buffer.offset + offset]; - if (offset + 3 < buffer.length) - val = val + (buffer.parent[buffer.offset + offset + 3] << 24 >>> 0); - } - - return val; -} - -Buffer.prototype.readUInt32LE = function(offset, noAssert) { - return readUInt32(this, offset, false, noAssert); -}; - -Buffer.prototype.readUInt32BE = function(offset, noAssert) { - return readUInt32(this, offset, true, noAssert); -}; - - -/* - * Signed integer types, yay team! A reminder on how two's complement actually - * works. The first bit is the signed bit, i.e. tells us whether or not the - * number should be positive or negative. If the two's complement value is - * positive, then we're done, as it's equivalent to the unsigned representation. - * - * Now if the number is positive, you're pretty much done, you can just leverage - * the unsigned translations and return those. Unfortunately, negative numbers - * aren't quite that straightforward. - * - * At first glance, one might be inclined to use the traditional formula to - * translate binary numbers between the positive and negative values in two's - * complement. (Though it doesn't quite work for the most negative value) - * Mainly: - * - invert all the bits - * - add one to the result - * - * Of course, this doesn't quite work in Javascript. Take for example the value - * of -128. This could be represented in 16 bits (big-endian) as 0xff80. But of - * course, Javascript will do the following: - * - * > ~0xff80 - * -65409 - * - * Whoh there, Javascript, that's not quite right. But wait, according to - * Javascript that's perfectly correct. When Javascript ends up seeing the - * constant 0xff80, it has no notion that it is actually a signed number. It - * assumes that we've input the unsigned value 0xff80. Thus, when it does the - * binary negation, it casts it into a signed value, (positive 0xff80). Then - * when you perform binary negation on that, it turns it into a negative number. - * - * Instead, we're going to have to use the following general formula, that works - * in a rather Javascript friendly way. I'm glad we don't support this kind of - * weird numbering scheme in the kernel. - * - * (BIT-MAX - (unsigned)val + 1) * -1 - * - * The astute observer, may think that this doesn't make sense for 8-bit numbers - * (really it isn't necessary for them). However, when you get 16-bit numbers, - * you do. Let's go back to our prior example and see how this will look: - * - * (0xffff - 0xff80 + 1) * -1 - * (0x007f + 1) * -1 - * (0x0080) * -1 - */ -Buffer.prototype.readInt8 = function(offset, noAssert) { - var buffer = this; - var neg; - - if (!noAssert) { - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset < buffer.length, - 'Trying to read beyond buffer length'); - } - - if (offset >= buffer.length) return; - - neg = buffer.parent[buffer.offset + offset] & 0x80; - if (!neg) { - return (buffer.parent[buffer.offset + offset]); - } - - return ((0xff - buffer.parent[buffer.offset + offset] + 1) * -1); -}; - -function readInt16(buffer, offset, isBigEndian, noAssert) { - var neg, val; - - if (!noAssert) { - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 1 < buffer.length, - 'Trying to read beyond buffer length'); - } - - val = readUInt16(buffer, offset, isBigEndian, noAssert); - neg = val & 0x8000; - if (!neg) { - return val; - } - - return (0xffff - val + 1) * -1; -} - -Buffer.prototype.readInt16LE = function(offset, noAssert) { - return readInt16(this, offset, false, noAssert); -}; - -Buffer.prototype.readInt16BE = function(offset, noAssert) { - return readInt16(this, offset, true, noAssert); -}; - -function readInt32(buffer, offset, isBigEndian, noAssert) { - var neg, val; - - if (!noAssert) { - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 3 < buffer.length, - 'Trying to read beyond buffer length'); - } - - val = readUInt32(buffer, offset, isBigEndian, noAssert); - neg = val & 0x80000000; - if (!neg) { - return (val); - } - - return (0xffffffff - val + 1) * -1; -} - -Buffer.prototype.readInt32LE = function(offset, noAssert) { - return readInt32(this, offset, false, noAssert); -}; - -Buffer.prototype.readInt32BE = function(offset, noAssert) { - return readInt32(this, offset, true, noAssert); -}; - -function readFloat(buffer, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset + 3 < buffer.length, - 'Trying to read beyond buffer length'); - } - - return require('./buffer_ieee754').readIEEE754(buffer, offset, isBigEndian, - 23, 4); -} - -Buffer.prototype.readFloatLE = function(offset, noAssert) { - return readFloat(this, offset, false, noAssert); -}; - -Buffer.prototype.readFloatBE = function(offset, noAssert) { - return readFloat(this, offset, true, noAssert); -}; - -function readDouble(buffer, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset + 7 < buffer.length, - 'Trying to read beyond buffer length'); - } - - return require('./buffer_ieee754').readIEEE754(buffer, offset, isBigEndian, - 52, 8); -} - -Buffer.prototype.readDoubleLE = function(offset, noAssert) { - return readDouble(this, offset, false, noAssert); -}; - -Buffer.prototype.readDoubleBE = function(offset, noAssert) { - return readDouble(this, offset, true, noAssert); -}; - - -/* - * We have to make sure that the value is a valid integer. This means that it is - * non-negative. It has no fractional component and that it does not exceed the - * maximum allowed value. - * - * value The number to check for validity - * - * max The maximum value - */ -function verifuint(value, max) { - assert.ok(typeof (value) == 'number', - 'cannot write a non-number as a number'); - - assert.ok(value >= 0, - 'specified a negative value for writing an unsigned value'); - - assert.ok(value <= max, 'value is larger than maximum value for type'); - - assert.ok(Math.floor(value) === value, 'value has a fractional component'); -} - -Buffer.prototype.writeUInt8 = function(value, offset, noAssert) { - var buffer = this; - - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset < buffer.length, - 'trying to write beyond buffer length'); - - verifuint(value, 0xff); - } - - if (offset < buffer.length) { - buffer.parent[buffer.offset + offset] = value; - } -}; - -function writeUInt16(buffer, value, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 1 < buffer.length, - 'trying to write beyond buffer length'); - - verifuint(value, 0xffff); - } - - for (var i = 0; i < Math.min(buffer.length - offset, 2); i++) { - buffer.parent[buffer.offset + offset + i] = - (value & (0xff << (8 * (isBigEndian ? 1 - i : i)))) >>> - (isBigEndian ? 1 - i : i) * 8; - } - -} - -Buffer.prototype.writeUInt16LE = function(value, offset, noAssert) { - writeUInt16(this, value, offset, false, noAssert); -}; - -Buffer.prototype.writeUInt16BE = function(value, offset, noAssert) { - writeUInt16(this, value, offset, true, noAssert); -}; - -function writeUInt32(buffer, value, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 3 < buffer.length, - 'trying to write beyond buffer length'); - - verifuint(value, 0xffffffff); - } - - for (var i = 0; i < Math.min(buffer.length - offset, 4); i++) { - buffer.parent[buffer.offset + offset + i] = - (value >>> (isBigEndian ? 3 - i : i) * 8) & 0xff; - } -} - -Buffer.prototype.writeUInt32LE = function(value, offset, noAssert) { - writeUInt32(this, value, offset, false, noAssert); -}; - -Buffer.prototype.writeUInt32BE = function(value, offset, noAssert) { - writeUInt32(this, value, offset, true, noAssert); -}; - - -/* - * We now move onto our friends in the signed number category. Unlike unsigned - * numbers, we're going to have to worry a bit more about how we put values into - * arrays. Since we are only worrying about signed 32-bit values, we're in - * slightly better shape. Unfortunately, we really can't do our favorite binary - * & in this system. It really seems to do the wrong thing. For example: - * - * > -32 & 0xff - * 224 - * - * What's happening above is really: 0xe0 & 0xff = 0xe0. However, the results of - * this aren't treated as a signed number. Ultimately a bad thing. - * - * What we're going to want to do is basically create the unsigned equivalent of - * our representation and pass that off to the wuint* functions. To do that - * we're going to do the following: - * - * - if the value is positive - * we can pass it directly off to the equivalent wuint - * - if the value is negative - * we do the following computation: - * mb + val + 1, where - * mb is the maximum unsigned value in that byte size - * val is the Javascript negative integer - * - * - * As a concrete value, take -128. In signed 16 bits this would be 0xff80. If - * you do out the computations: - * - * 0xffff - 128 + 1 - * 0xffff - 127 - * 0xff80 - * - * You can then encode this value as the signed version. This is really rather - * hacky, but it should work and get the job done which is our goal here. - */ - -/* - * A series of checks to make sure we actually have a signed 32-bit number - */ -function verifsint(value, max, min) { - assert.ok(typeof (value) == 'number', - 'cannot write a non-number as a number'); - - assert.ok(value <= max, 'value larger than maximum allowed value'); - - assert.ok(value >= min, 'value smaller than minimum allowed value'); - - assert.ok(Math.floor(value) === value, 'value has a fractional component'); -} - -function verifIEEE754(value, max, min) { - assert.ok(typeof (value) == 'number', - 'cannot write a non-number as a number'); - - assert.ok(value <= max, 'value larger than maximum allowed value'); - - assert.ok(value >= min, 'value smaller than minimum allowed value'); -} - -Buffer.prototype.writeInt8 = function(value, offset, noAssert) { - var buffer = this; - - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset < buffer.length, - 'Trying to write beyond buffer length'); - - verifsint(value, 0x7f, -0x80); - } - - if (value >= 0) { - buffer.writeUInt8(value, offset, noAssert); - } else { - buffer.writeUInt8(0xff + value + 1, offset, noAssert); - } -}; - -function writeInt16(buffer, value, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 1 < buffer.length, - 'Trying to write beyond buffer length'); - - verifsint(value, 0x7fff, -0x8000); - } - - if (value >= 0) { - writeUInt16(buffer, value, offset, isBigEndian, noAssert); - } else { - writeUInt16(buffer, 0xffff + value + 1, offset, isBigEndian, noAssert); - } -} - -Buffer.prototype.writeInt16LE = function(value, offset, noAssert) { - writeInt16(this, value, offset, false, noAssert); -}; - -Buffer.prototype.writeInt16BE = function(value, offset, noAssert) { - writeInt16(this, value, offset, true, noAssert); -}; - -function writeInt32(buffer, value, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 3 < buffer.length, - 'Trying to write beyond buffer length'); - - verifsint(value, 0x7fffffff, -0x80000000); - } - - if (value >= 0) { - writeUInt32(buffer, value, offset, isBigEndian, noAssert); - } else { - writeUInt32(buffer, 0xffffffff + value + 1, offset, isBigEndian, noAssert); - } -} - -Buffer.prototype.writeInt32LE = function(value, offset, noAssert) { - writeInt32(this, value, offset, false, noAssert); -}; - -Buffer.prototype.writeInt32BE = function(value, offset, noAssert) { - writeInt32(this, value, offset, true, noAssert); -}; - -function writeFloat(buffer, value, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 3 < buffer.length, - 'Trying to write beyond buffer length'); - - verifIEEE754(value, 3.4028234663852886e+38, -3.4028234663852886e+38); - } - - require('./buffer_ieee754').writeIEEE754(buffer, value, offset, isBigEndian, - 23, 4); -} - -Buffer.prototype.writeFloatLE = function(value, offset, noAssert) { - writeFloat(this, value, offset, false, noAssert); -}; - -Buffer.prototype.writeFloatBE = function(value, offset, noAssert) { - writeFloat(this, value, offset, true, noAssert); -}; - -function writeDouble(buffer, value, offset, isBigEndian, noAssert) { - if (!noAssert) { - assert.ok(value !== undefined && value !== null, - 'missing value'); - - assert.ok(typeof (isBigEndian) === 'boolean', - 'missing or invalid endian'); - - assert.ok(offset !== undefined && offset !== null, - 'missing offset'); - - assert.ok(offset + 7 < buffer.length, - 'Trying to write beyond buffer length'); - - verifIEEE754(value, 1.7976931348623157E+308, -1.7976931348623157E+308); - } - - require('./buffer_ieee754').writeIEEE754(buffer, value, offset, isBigEndian, - 52, 8); -} - -Buffer.prototype.writeDoubleLE = function(value, offset, noAssert) { - writeDouble(this, value, offset, false, noAssert); -}; - -Buffer.prototype.writeDoubleBE = function(value, offset, noAssert) { - writeDouble(this, value, offset, true, noAssert); -}; - -SlowBuffer.prototype.readUInt8 = Buffer.prototype.readUInt8; -SlowBuffer.prototype.readUInt16LE = Buffer.prototype.readUInt16LE; -SlowBuffer.prototype.readUInt16BE = Buffer.prototype.readUInt16BE; -SlowBuffer.prototype.readUInt32LE = Buffer.prototype.readUInt32LE; -SlowBuffer.prototype.readUInt32BE = Buffer.prototype.readUInt32BE; -SlowBuffer.prototype.readInt8 = Buffer.prototype.readInt8; -SlowBuffer.prototype.readInt16LE = Buffer.prototype.readInt16LE; -SlowBuffer.prototype.readInt16BE = Buffer.prototype.readInt16BE; -SlowBuffer.prototype.readInt32LE = Buffer.prototype.readInt32LE; -SlowBuffer.prototype.readInt32BE = Buffer.prototype.readInt32BE; -SlowBuffer.prototype.readFloatLE = Buffer.prototype.readFloatLE; -SlowBuffer.prototype.readFloatBE = Buffer.prototype.readFloatBE; -SlowBuffer.prototype.readDoubleLE = Buffer.prototype.readDoubleLE; -SlowBuffer.prototype.readDoubleBE = Buffer.prototype.readDoubleBE; -SlowBuffer.prototype.writeUInt8 = Buffer.prototype.writeUInt8; -SlowBuffer.prototype.writeUInt16LE = Buffer.prototype.writeUInt16LE; -SlowBuffer.prototype.writeUInt16BE = Buffer.prototype.writeUInt16BE; -SlowBuffer.prototype.writeUInt32LE = Buffer.prototype.writeUInt32LE; -SlowBuffer.prototype.writeUInt32BE = Buffer.prototype.writeUInt32BE; -SlowBuffer.prototype.writeInt8 = Buffer.prototype.writeInt8; -SlowBuffer.prototype.writeInt16LE = Buffer.prototype.writeInt16LE; -SlowBuffer.prototype.writeInt16BE = Buffer.prototype.writeInt16BE; -SlowBuffer.prototype.writeInt32LE = Buffer.prototype.writeInt32LE; -SlowBuffer.prototype.writeInt32BE = Buffer.prototype.writeInt32BE; -SlowBuffer.prototype.writeFloatLE = Buffer.prototype.writeFloatLE; -SlowBuffer.prototype.writeFloatBE = Buffer.prototype.writeFloatBE; -SlowBuffer.prototype.writeDoubleLE = Buffer.prototype.writeDoubleLE; -SlowBuffer.prototype.writeDoubleBE = Buffer.prototype.writeDoubleBE; -- 2.34.1