CasperSecurity
'use strict';
var zlib_inflate = require('./zlib/inflate');
var utils = require('./utils/common');
var strings = require('./utils/strings');
var c = require('./zlib/constants');
var msg = require('./zlib/messages');
var ZStream = require('./zlib/zstream');
var GZheader = require('./zlib/gzheader');
var toString = Object.prototype.toString;
/**
* class Inflate
*
* Generic JS-style wrapper for zlib calls. If you don't need
* streaming behaviour - use more simple functions: [[inflate]]
* and [[inflateRaw]].
**/
/* internal
* inflate.chunks -> Array
*
* Chunks of output data, if [[Inflate#onData]] not overridden.
**/
/**
* Inflate.result -> Uint8Array|Array|String
*
* Uncompressed result, generated by default [[Inflate#onData]]
* and [[Inflate#onEnd]] handlers. Filled after you push last chunk
* (call [[Inflate#push]] with `Z_FINISH` / `true` param) or if you
* push a chunk with explicit flush (call [[Inflate#push]] with
* `Z_SYNC_FLUSH` param).
**/
/**
* Inflate.err -> Number
*
* Error code after inflate finished. 0 (Z_OK) on success.
* Should be checked if broken data possible.
**/
/**
* Inflate.msg -> String
*
* Error message, if [[Inflate.err]] != 0
**/
/**
* new Inflate(options)
* - options (Object): zlib inflate options.
*
* Creates new inflator instance with specified params. Throws exception
* on bad params. Supported options:
*
* - `windowBits`
* - `dictionary`
*
* [http://zlib.net/manual.html#Advanced](http://zlib.net/manual.html#Advanced)
* for more information on these.
*
* Additional options, for internal needs:
*
* - `chunkSize` - size of generated data chunks (16K by default)
* - `raw` (Boolean) - do raw inflate
* - `to` (String) - if equal to 'string', then result will be converted
* from utf8 to utf16 (javascript) string. When string output requested,
* chunk length can differ from `chunkSize`, depending on content.
*
* By default, when no options set, autodetect deflate/gzip data format via
* wrapper header.
*
* ##### Example:
*
* ```javascript
* var pako = require('pako')
* , chunk1 = Uint8Array([1,2,3,4,5,6,7,8,9])
* , chunk2 = Uint8Array([10,11,12,13,14,15,16,17,18,19]);
*
* var inflate = new pako.Inflate({ level: 3});
*
* inflate.push(chunk1, false);
* inflate.push(chunk2, true); // true -> last chunk
*
* if (inflate.err) { throw new Error(inflate.err); }
*
* console.log(inflate.result);
* ```
**/
function Inflate(options) {
if (!(this instanceof Inflate)) return new Inflate(options);
this.options = utils.assign({
chunkSize: 16384,
windowBits: 0,
to: ''
}, options || {});
var opt = this.options;
// Force window size for `raw` data, if not set directly,
// because we have no header for autodetect.
if (opt.raw && (opt.windowBits >= 0) && (opt.windowBits < 16)) {
opt.windowBits = -opt.windowBits;
if (opt.windowBits === 0) { opt.windowBits = -15; }
}
// If `windowBits` not defined (and mode not raw) - set autodetect flag for gzip/deflate
if ((opt.windowBits >= 0) && (opt.windowBits < 16) &&
!(options && options.windowBits)) {
opt.windowBits += 32;
}
// Gzip header has no info about windows size, we can do autodetect only
// for deflate. So, if window size not set, force it to max when gzip possible
if ((opt.windowBits > 15) && (opt.windowBits < 48)) {
// bit 3 (16) -> gzipped data
// bit 4 (32) -> autodetect gzip/deflate
if ((opt.windowBits & 15) === 0) {
opt.windowBits |= 15;
}
}
this.err = 0; // error code, if happens (0 = Z_OK)
this.msg = ''; // error message
this.ended = false; // used to avoid multiple onEnd() calls
this.chunks = []; // chunks of compressed data
this.strm = new ZStream();
this.strm.avail_out = 0;
var status = zlib_inflate.inflateInit2(
this.strm,
opt.windowBits
);
if (status !== c.Z_OK) {
throw new Error(msg[status]);
}
this.header = new GZheader();
zlib_inflate.inflateGetHeader(this.strm, this.header);
// Setup dictionary
if (opt.dictionary) {
// Convert data if needed
if (typeof opt.dictionary === 'string') {
opt.dictionary = strings.string2buf(opt.dictionary);
} else if (toString.call(opt.dictionary) === '[object ArrayBuffer]') {
opt.dictionary = new Uint8Array(opt.dictionary);
}
if (opt.raw) { //In raw mode we need to set the dictionary early
status = zlib_inflate.inflateSetDictionary(this.strm, opt.dictionary);
if (status !== c.Z_OK) {
throw new Error(msg[status]);
}
}
}
}
/**
* Inflate#push(data[, mode]) -> Boolean
* - data (Uint8Array|Array|ArrayBuffer|String): input data
* - mode (Number|Boolean): 0..6 for corresponding Z_NO_FLUSH..Z_TREE modes.
* See constants. Skipped or `false` means Z_NO_FLUSH, `true` means Z_FINISH.
*
* Sends input data to inflate pipe, generating [[Inflate#onData]] calls with
* new output chunks. Returns `true` on success. The last data block must have
* mode Z_FINISH (or `true`). That will flush internal pending buffers and call
* [[Inflate#onEnd]]. For interim explicit flushes (without ending the stream) you
* can use mode Z_SYNC_FLUSH, keeping the decompression context.
*
* On fail call [[Inflate#onEnd]] with error code and return false.
*
* We strongly recommend to use `Uint8Array` on input for best speed (output
* format is detected automatically). Also, don't skip last param and always
* use the same type in your code (boolean or number). That will improve JS speed.
*
* For regular `Array`-s make sure all elements are [0..255].
*
* ##### Example
*
* ```javascript
* push(chunk, false); // push one of data chunks
* ...
* push(chunk, true); // push last chunk
* ```
**/
Inflate.prototype.push = function (data, mode) {
var strm = this.strm;
var chunkSize = this.options.chunkSize;
var dictionary = this.options.dictionary;
var status, _mode;
var next_out_utf8, tail, utf8str;
// Flag to properly process Z_BUF_ERROR on testing inflate call
// when we check that all output data was flushed.
var allowBufError = false;
if (this.ended) { return false; }
_mode = (mode === ~~mode) ? mode : ((mode === true) ? c.Z_FINISH : c.Z_NO_FLUSH);
// Convert data if needed
if (typeof data === 'string') {
// Only binary strings can be decompressed on practice
strm.input = strings.binstring2buf(data);
} else if (toString.call(data) === '[object ArrayBuffer]') {
strm.input = new Uint8Array(data);
} else {
strm.input = data;
}
strm.next_in = 0;
strm.avail_in = strm.input.length;
do {
if (strm.avail_out === 0) {
strm.output = new utils.Buf8(chunkSize);
strm.next_out = 0;
strm.avail_out = chunkSize;
}
status = zlib_inflate.inflate(strm, c.Z_NO_FLUSH); /* no bad return value */
if (status === c.Z_NEED_DICT && dictionary) {
status = zlib_inflate.inflateSetDictionary(this.strm, dictionary);
}
if (status === c.Z_BUF_ERROR && allowBufError === true) {
status = c.Z_OK;
allowBufError = false;
}
if (status !== c.Z_STREAM_END && status !== c.Z_OK) {
this.onEnd(status);
this.ended = true;
return false;
}
if (strm.next_out) {
if (strm.avail_out === 0 || status === c.Z_STREAM_END || (strm.avail_in === 0 && (_mode === c.Z_FINISH || _mode === c.Z_SYNC_FLUSH))) {
if (this.options.to === 'string') {
next_out_utf8 = strings.utf8border(strm.output, strm.next_out);
tail = strm.next_out - next_out_utf8;
utf8str = strings.buf2string(strm.output, next_out_utf8);
// move tail
strm.next_out = tail;
strm.avail_out = chunkSize - tail;
if (tail) { utils.arraySet(strm.output, strm.output, next_out_utf8, tail, 0); }
this.onData(utf8str);
} else {
this.onData(utils.shrinkBuf(strm.output, strm.next_out));
}
}
}
// When no more input data, we should check that internal inflate buffers
// are flushed. The only way to do it when avail_out = 0 - run one more
// inflate pass. But if output data not exists, inflate return Z_BUF_ERROR.
// Here we set flag to process this error properly.
//
// NOTE. Deflate does not return error in this case and does not needs such
// logic.
if (strm.avail_in === 0 && strm.avail_out === 0) {
allowBufError = true;
}
} while ((strm.avail_in > 0 || strm.avail_out === 0) && status !== c.Z_STREAM_END);
if (status === c.Z_STREAM_END) {
_mode = c.Z_FINISH;
}
// Finalize on the last chunk.
if (_mode === c.Z_FINISH) {
status = zlib_inflate.inflateEnd(this.strm);
this.onEnd(status);
this.ended = true;
return status === c.Z_OK;
}
// callback interim results if Z_SYNC_FLUSH.
if (_mode === c.Z_SYNC_FLUSH) {
this.onEnd(c.Z_OK);
strm.avail_out = 0;
return true;
}
return true;
};
/**
* Inflate#onData(chunk) -> Void
* - chunk (Uint8Array|Array|String): output data. Type of array depends
* on js engine support. When string output requested, each chunk
* will be string.
*
* By default, stores data blocks in `chunks[]` property and glue
* those in `onEnd`. Override this handler, if you need another behaviour.
**/
Inflate.prototype.onData = function (chunk) {
this.chunks.push(chunk);
};
/**
* Inflate#onEnd(status) -> Void
* - status (Number): inflate status. 0 (Z_OK) on success,
* other if not.
*
* Called either after you tell inflate that the input stream is
* complete (Z_FINISH) or should be flushed (Z_SYNC_FLUSH)
* or if an error happened. By default - join collected chunks,
* free memory and fill `results` / `err` properties.
**/
Inflate.prototype.onEnd = function (status) {
// On success - join
if (status === c.Z_OK) {
if (this.options.to === 'string') {
// Glue & convert here, until we teach pako to send
// utf8 aligned strings to onData
this.result = this.chunks.join('');
} else {
this.result = utils.flattenChunks(this.chunks);
}
}
this.chunks = [];
this.err = status;
this.msg = this.strm.msg;
};
/**
* inflate(data[, options]) -> Uint8Array|Array|String
* - data (Uint8Array|Array|String): input data to decompress.
* - options (Object): zlib inflate options.
*
* Decompress `data` with inflate/ungzip and `options`. Autodetect
* format via wrapper header by default. That's why we don't provide
* separate `ungzip` method.
*
* Supported options are:
*
* - windowBits
*
* [http://zlib.net/manual.html#Advanced](http://zlib.net/manual.html#Advanced)
* for more information.
*
* Sugar (options):
*
* - `raw` (Boolean) - say that we work with raw stream, if you don't wish to specify
* negative windowBits implicitly.
* - `to` (String) - if equal to 'string', then result will be converted
* from utf8 to utf16 (javascript) string. When string output requested,
* chunk length can differ from `chunkSize`, depending on content.
*
*
* ##### Example:
*
* ```javascript
* var pako = require('pako')
* , input = pako.deflate([1,2,3,4,5,6,7,8,9])
* , output;
*
* try {
* output = pako.inflate(input);
* } catch (err)
* console.log(err);
* }
* ```
**/
function inflate(input, options) {
var inflator = new Inflate(options);
inflator.push(input, true);
// That will never happens, if you don't cheat with options :)
if (inflator.err) { throw inflator.msg || msg[inflator.err]; }
return inflator.result;
}
/**
* inflateRaw(data[, options]) -> Uint8Array|Array|String
* - data (Uint8Array|Array|String): input data to decompress.
* - options (Object): zlib inflate options.
*
* The same as [[inflate]], but creates raw data, without wrapper
* (header and adler32 crc).
**/
function inflateRaw(input, options) {
options = options || {};
options.raw = true;
return inflate(input, options);
}
/**
* ungzip(data[, options]) -> Uint8Array|Array|String
* - data (Uint8Array|Array|String): input data to decompress.
* - options (Object): zlib inflate options.
*
* Just shortcut to [[inflate]], because it autodetects format
* by header.content. Done for convenience.
**/
exports.Inflate = Inflate;
exports.inflate = inflate;
exports.inflateRaw = inflateRaw;
exports.ungzip = inflate;