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jsdoc tweaks

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codedread 2013-07-08 22:12:12 -07:00
parent 262d86c17f
commit 6d86b98b95
1 changed files with 80 additions and 39 deletions
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103
io.js
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@ -27,11 +27,11 @@ var BITMASK = [0, 0x01, 0x03, 0x07, 0x0F, 0x1F, 0x3F, 0x7F, 0xFF ];
/**
* This bit stream peeks and consumes bits out of a binary stream.
*
* {ArrayBuffer} ab An ArrayBuffer object or a Uint8Array.
* {boolean} rtl Whether the stream reads bits from the byte starting
* @param {ArrayBuffer} ab An ArrayBuffer object or a Uint8Array.
* @param {boolean} rtl Whether the stream reads bits from the byte starting
* from bit 7 to 0 (true) or bit 0 to 7 (false).
* {Number} opt_offset The offset into the ArrayBuffer
* {Number} opt_length The length of this BitStream
* @param {Number} opt_offset The offset into the ArrayBuffer
* @param {Number} opt_length The length of this BitStream
*/
bitjs.io.BitStream = function(ab, rtl, opt_offset, opt_length) {
if (!ab || !ab.toString || ab.toString() !== "[object ArrayBuffer]") {
@ -46,11 +46,14 @@ bitjs.io.BitStream = function(ab, rtl, opt_offset, opt_length) {
this.peekBits = rtl ? this.peekBits_rtl : this.peekBits_ltr;
};
// byte0 byte1 byte2 byte3
// 7......0 | 7......0 | 7......0 | 7......0
//
// The bit pointer starts at bit0 of byte0 and moves left until it reaches
// bit7 of byte0, then jumps to bit0 of byte1, etc.
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit0 of byte0 and moves left until it reaches
* bit7 of byte0, then jumps to bit0 of byte1, etc.
*/
bitjs.io.BitStream.prototype.peekBits_ltr = function(n, movePointers) {
if (n <= 0 || typeof n != typeof 1) {
return 0;
@ -102,11 +105,14 @@ bitjs.io.BitStream.prototype.peekBits_ltr = function(n, movePointers) {
return result;
};
// byte0 byte1 byte2 byte3
// 7......0 | 7......0 | 7......0 | 7......0
//
// The bit pointer starts at bit7 of byte0 and moves right until it reaches
// bit0 of byte0, then goes to bit7 of byte1, etc.
/**
* byte0 byte1 byte2 byte3
* 7......0 | 7......0 | 7......0 | 7......0
*
* The bit pointer starts at bit7 of byte0 and moves right until it reaches
* bit0 of byte0, then goes to bit7 of byte1, etc.
*/
bitjs.io.BitStream.prototype.peekBits_rtl = function(n, movePointers) {
if (n <= 0 || typeof n != typeof 1) {
return 0;
@ -155,21 +161,29 @@ bitjs.io.BitStream.prototype.peekBits_rtl = function(n, movePointers) {
return result;
};
//some voodoo magic
/**
* Some voodoo magic.
*/
bitjs.io.BitStream.prototype.getBits = function() {
return (((((this.bytes[this.bytePtr] & 0xff) << 16) +
((this.bytes[this.bytePtr+1] & 0xff) << 8) +
((this.bytes[this.bytePtr+2] & 0xff))) >>> (8-this.bitPtr)) & 0xffff);
};
/**
*/
bitjs.io.BitStream.prototype.readBits = function(n) {
return this.peekBits(n, true);
};
// This returns n bytes as a sub-array, advancing the pointer if movePointers
// is true.
// Only use this for uncompressed blocks as this throws away remaining bits in
// the current byte.
/**
* This returns n bytes as a sub-array, advancing the pointer if movePointers
* is true. Only use this for uncompressed blocks as this throws away remaining
* bits in the current byte.
*/
bitjs.io.BitStream.prototype.peekBytes = function(n, movePointers) {
if (n <= 0 || typeof n != typeof 1) {
return 0;
@ -194,6 +208,9 @@ bitjs.io.BitStream.prototype.peekBytes = function(n, movePointers) {
return result;
};
/**
*/
bitjs.io.BitStream.prototype.readBytes = function(n) {
return this.peekBytes(n, true);
};
@ -206,9 +223,9 @@ bitjs.io.BitStream.prototype.readBytes = function( n ) {
* This object is much easier to write than the above BitStream since
* everything is byte-aligned.
*
* {ArrayBuffer} ab The ArrayBuffer object.
* {Number} opt_offset The offset into the ArrayBuffer
* {Number} opt_length The length of this BitStream
* @param {ArrayBuffer} ab The ArrayBuffer object.
* @param {Number} opt_offset The offset into the ArrayBuffer
* @param {Number} opt_length The length of this BitStream
*/
bitjs.io.ByteStream = function(ab, opt_offset, opt_length) {
var offset = opt_offset || 0;
@ -217,8 +234,12 @@ bitjs.io.ByteStream = function(ab, opt_offset, opt_length) {
this.ptr = 0;
};
// peeks at the next n bytes as an unsigned number but does not advance the pointer
// TODO: This apparently cannot read more than 4 bytes as a number?
/**
* Peeks at the next n bytes as an unsigned number but does not advance the
* pointer.
* TODO: This apparently cannot read more than 4 bytes as a number?
*/
bitjs.io.ByteStream.prototype.peekNumber = function(n) {
// TODO: return error if n would go past the end of the stream?
if (n <= 0 || typeof n != typeof 1)
@ -235,16 +256,22 @@ bitjs.io.ByteStream.prototype.peekNumber = function( n ) {
return result;
};
// returns the next n bytes as an unsigned number (or -1 on error)
// and advances the stream pointer n bytes
/**
* Returns the next n bytes as an unsigned number (or -1 on error) and advances
* the stream pointer n bytes.
*/
bitjs.io.ByteStream.prototype.readNumber = function(n) {
var num = this.peekNumber( n );
this.ptr += n;
return num;
};
// This returns n bytes as a sub-array, advancing the pointer if movePointers
// is true.
/**
* This returns n bytes as a sub-array, advancing the pointer if movePointers
* is true.
*/
bitjs.io.ByteStream.prototype.peekBytes = function(n, movePointers) {
if (n <= 0 || typeof n != typeof 1) {
return 0;
@ -259,11 +286,17 @@ bitjs.io.ByteStream.prototype.peekBytes = function(n, movePointers) {
return result;
};
/**
*/
bitjs.io.ByteStream.prototype.readBytes = function(n) {
return this.peekBytes(n, true);
};
// peeks at the next n bytes as a string but does not advance the pointer
/**
* Peeks at the next n bytes as a string but does not advance the pointer.
*/
bitjs.io.ByteStream.prototype.peekString = function(n) {
if (n <= 0 || typeof n != typeof 1) {
return 0;
@ -276,8 +309,10 @@ bitjs.io.ByteStream.prototype.peekString = function( n ) {
return result;
};
// returns the next n bytes as a string
// and advances the stream pointer n bytes
/**
* Returns the next n bytes as a string and advances the stream pointer n bytes.
*/
bitjs.io.ByteStream.prototype.readString = function(n) {
var strToReturn = this.peekString(n);
this.ptr += n;
@ -296,11 +331,17 @@ bitjs.io.ByteBuffer = function(numBytes) {
this.ptr = 0;
};
/**
*/
bitjs.io.ByteBuffer.prototype.insertByte = function(b) {
// TODO: throw if byte is invalid?
this.data[this.ptr++] = b;
};
/**
*/
bitjs.io.ByteBuffer.prototype.insertBytes = function(bytes) {
// TODO: throw if bytes is invalid?
this.data.set(bytes, this.ptr);