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移除多余文件, 改用esbuild打包;调整为esm语法

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yutent 2023-04-13 00:28:14 +08:00
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.nyc_output
doc/
node_modules/
dist/
*.log
package-lock.json
test.js

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(The MIT License)
Copyright (C) 2014-2017 by Vitaly Puzrin and Andrei Tuputcyn
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

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## @bytedo/gzip
> 浏览器端的gzip库, fork于pako, 仅调整语法为esm, 并只保留gzip的导出。
### 安装&使用
```bash
npm install @bytedo/gzip
```
或直接使用cdn地址:
```js
import { gzip , ungzip } from '@bytedo/gzip' // use importmap
// or
import { gzip , ungzip } from '//jscdn.ink/@bytedo/gzip/latest/index.js'
let res = gzip('hello world') // return Uint8Array object
let txt = ungzip(res) // hello world
```
### 开源协议
- MIT - 除 `/lib/zlib` 目录以外的所有文件
- ZLIB - `/lib/zlib` 目录

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export { gzip } from './lib/deflate.js'
export { ungzip } from './lib/inflate.js'

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import zlib_deflate from './zlib/deflate.js'
import { flattenChunks } from './utils/common.js'
import { string2buf } from './utils/strings.js'
import msg from './zlib/messages.js'
import ZStream from './zlib/zstream.js'
const toString = Object.prototype.toString
/* Public constants ==========================================================*/
/* ===========================================================================*/
import {
Z_NO_FLUSH,
Z_SYNC_FLUSH,
Z_FULL_FLUSH,
Z_FINISH,
Z_OK,
Z_STREAM_END,
Z_DEFAULT_COMPRESSION,
Z_DEFAULT_STRATEGY,
Z_DEFLATED
} from './zlib/constants.js'
/* ===========================================================================*/
/**
* class Deflate
*
* Generic JS-style wrapper for zlib calls. If you don't need
* streaming behaviour - use more simple functions: [[deflate]],
* [[deflateRaw]] and [[gzip]].
**/
/* internal
* Deflate.chunks -> Array
*
* Chunks of output data, if [[Deflate#onData]] not overridden.
**/
/**
* Deflate.result -> Uint8Array
*
* Compressed result, generated by default [[Deflate#onData]]
* and [[Deflate#onEnd]] handlers. Filled after you push last chunk
* (call [[Deflate#push]] with `Z_FINISH` / `true` param).
**/
/**
* Deflate.err -> Number
*
* Error code after deflate finished. 0 (Z_OK) on success.
* You will not need it in real life, because deflate errors
* are possible only on wrong options or bad `onData` / `onEnd`
* custom handlers.
**/
/**
* Deflate.msg -> String
*
* Error message, if [[Deflate.err]] != 0
**/
/**
* new Deflate(options)
* - options (Object): zlib deflate options.
*
* Creates new deflator instance with specified params. Throws exception
* on bad params. Supported options:
*
* - `level`
* - `windowBits`
* - `memLevel`
* - `strategy`
* - `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 deflate
* - `gzip` (Boolean) - create gzip wrapper
* - `header` (Object) - custom header for gzip
* - `text` (Boolean) - true if compressed data believed to be text
* - `time` (Number) - modification time, unix timestamp
* - `os` (Number) - operation system code
* - `extra` (Array) - array of bytes with extra data (max 65536)
* - `name` (String) - file name (binary string)
* - `comment` (String) - comment (binary string)
* - `hcrc` (Boolean) - true if header crc should be added
*
* ##### Example:
*
* ```javascript
* const pako from 'pako')
* , chunk1 = new Uint8Array([1,2,3,4,5,6,7,8,9])
* , chunk2 = new Uint8Array([10,11,12,13,14,15,16,17,18,19]);
*
* const deflate = new pako.Deflate({ level: 3});
*
* deflate.push(chunk1, false);
* deflate.push(chunk2, true); // true -> last chunk
*
* if (deflate.err) { throw new Error(deflate.err); }
*
* console.log(deflate.result);
* ```
**/
function Deflate(options) {
this.options = Object.assign(
{
level: Z_DEFAULT_COMPRESSION,
method: Z_DEFLATED,
chunkSize: 16384,
windowBits: 15,
memLevel: 8,
strategy: Z_DEFAULT_STRATEGY
},
options || {}
)
let opt = this.options
if (opt.raw && opt.windowBits > 0) {
opt.windowBits = -opt.windowBits
} else if (opt.gzip && opt.windowBits > 0 && opt.windowBits < 16) {
opt.windowBits += 16
}
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
let status = zlib_deflate.deflateInit2(
this.strm,
opt.level,
opt.method,
opt.windowBits,
opt.memLevel,
opt.strategy
)
if (status !== Z_OK) {
throw new Error(msg[status])
}
if (opt.header) {
zlib_deflate.deflateSetHeader(this.strm, opt.header)
}
if (opt.dictionary) {
let dict
// Convert data if needed
if (typeof opt.dictionary === 'string') {
// If we need to compress text, change encoding to utf8.
dict = string2buf(opt.dictionary)
} else if (toString.call(opt.dictionary) === '[object ArrayBuffer]') {
dict = new Uint8Array(opt.dictionary)
} else {
dict = opt.dictionary
}
status = zlib_deflate.deflateSetDictionary(this.strm, dict)
if (status !== Z_OK) {
throw new Error(msg[status])
}
this._dict_set = true
}
}
/**
* Deflate#push(data[, flush_mode]) -> Boolean
* - data (Uint8Array|ArrayBuffer|String): input data. Strings will be
* converted to utf8 byte sequence.
* - flush_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 deflate pipe, generating [[Deflate#onData]] calls with
* new compressed chunks. Returns `true` on success. The last data block must
* have `flush_mode` Z_FINISH (or `true`). That will flush internal pending
* buffers and call [[Deflate#onEnd]].
*
* On fail call [[Deflate#onEnd]] with error code and return false.
*
* ##### Example
*
* ```javascript
* push(chunk, false); // push one of data chunks
* ...
* push(chunk, true); // push last chunk
* ```
**/
Deflate.prototype.push = function (data, flush_mode) {
const strm = this.strm
const chunkSize = this.options.chunkSize
let status, _flush_mode
if (this.ended) {
return false
}
if (flush_mode === ~~flush_mode) _flush_mode = flush_mode
else _flush_mode = flush_mode === true ? Z_FINISH : Z_NO_FLUSH
// Convert data if needed
if (typeof data === 'string') {
// If we need to compress text, change encoding to utf8.
strm.input = string2buf(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
for (;;) {
if (strm.avail_out === 0) {
strm.output = new Uint8Array(chunkSize)
strm.next_out = 0
strm.avail_out = chunkSize
}
// Make sure avail_out > 6 to avoid repeating markers
if (
(_flush_mode === Z_SYNC_FLUSH || _flush_mode === Z_FULL_FLUSH) &&
strm.avail_out <= 6
) {
this.onData(strm.output.subarray(0, strm.next_out))
strm.avail_out = 0
continue
}
status = zlib_deflate.deflate(strm, _flush_mode)
// Ended => flush and finish
if (status === Z_STREAM_END) {
if (strm.next_out > 0) {
this.onData(strm.output.subarray(0, strm.next_out))
}
status = zlib_deflate.deflateEnd(this.strm)
this.onEnd(status)
this.ended = true
return status === Z_OK
}
// Flush if out buffer full
if (strm.avail_out === 0) {
this.onData(strm.output)
continue
}
// Flush if requested and has data
if (_flush_mode > 0 && strm.next_out > 0) {
this.onData(strm.output.subarray(0, strm.next_out))
strm.avail_out = 0
continue
}
if (strm.avail_in === 0) break
}
return true
}
/**
* Deflate#onData(chunk) -> Void
* - chunk (Uint8Array): output data.
*
* By default, stores data blocks in `chunks[]` property and glue
* those in `onEnd`. Override this handler, if you need another behaviour.
**/
Deflate.prototype.onData = function (chunk) {
this.chunks.push(chunk)
}
/**
* Deflate#onEnd(status) -> Void
* - status (Number): deflate status. 0 (Z_OK) on success,
* other if not.
*
* Called once after you tell deflate that the input stream is
* complete (Z_FINISH). By default - join collected chunks,
* free memory and fill `results` / `err` properties.
**/
Deflate.prototype.onEnd = function (status) {
// On success - join
if (status === Z_OK) {
this.result = flattenChunks(this.chunks)
}
this.chunks = []
this.err = status
this.msg = this.strm.msg
}
/**
* deflate(data[, options]) -> Uint8Array
* - data (Uint8Array|ArrayBuffer|String): input data to compress.
* - options (Object): zlib deflate options.
*
* Compress `data` with deflate algorithm and `options`.
*
* Supported options are:
*
* - level
* - windowBits
* - memLevel
* - strategy
* - dictionary
*
* [http://zlib.net/manual.html#Advanced](http://zlib.net/manual.html#Advanced)
* for more information on these.
*
* Sugar (options):
*
* - `raw` (Boolean) - say that we work with raw stream, if you don't wish to specify
* negative windowBits implicitly.
*
* ##### Example:
*
* ```javascript
* const pako from 'pako')
* const data = new Uint8Array([1,2,3,4,5,6,7,8,9]);
*
* console.log(pako.deflate(data));
* ```
**/
function deflate(input, options) {
const deflator = new Deflate(options)
deflator.push(input, true)
// That will never happens, if you don't cheat with options :)
if (deflator.err) {
throw deflator.msg || msg[deflator.err]
}
return deflator.result
}
/**
* gzip(data[, options]) -> Uint8Array
* - data (Uint8Array|ArrayBuffer|String): input data to compress.
* - options (Object): zlib deflate options.
*
* The same as [[deflate]], but create gzip wrapper instead of
* deflate one.
**/
function gzip(input, options) {
options = options || {}
options.gzip = true
return deflate(input, options)
}
export { gzip }

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import zlib_inflate from './zlib/inflate.js'
import { flattenChunks } from './utils/common.js'
import { string2buf, utf8border, buf2string } from './utils/strings.js'
import msg from './zlib/messages.js'
import ZStream from './zlib/zstream.js'
import GZheader from './zlib/gzheader.js'
const toString = Object.prototype.toString
/* Public constants ==========================================================*/
/* ===========================================================================*/
import {
Z_NO_FLUSH,
Z_FINISH,
Z_OK,
Z_STREAM_END,
Z_NEED_DICT,
Z_STREAM_ERROR,
Z_DATA_ERROR,
Z_MEM_ERROR
} from './zlib/constants.js'
/* ===========================================================================*/
/**
* 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|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).
**/
/**
* 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
* const pako from 'pako')
* const chunk1 = new Uint8Array([1,2,3,4,5,6,7,8,9])
* const chunk2 = new Uint8Array([10,11,12,13,14,15,16,17,18,19]);
*
* const 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) {
this.options = Object.assign(
{
chunkSize: 1024 * 64,
windowBits: 15,
to: ''
},
options || {}
)
const 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
let status = zlib_inflate.inflateInit2(this.strm, opt.windowBits)
if (status !== 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 = 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 !== Z_OK) {
throw new Error(msg[status])
}
}
}
}
/**
* Inflate#push(data[, flush_mode]) -> Boolean
* - data (Uint8Array|ArrayBuffer): input data
* - flush_mode (Number|Boolean): 0..6 for corresponding Z_NO_FLUSH..Z_TREE
* flush 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. If end of stream detected,
* [[Inflate#onEnd]] will be called.
*
* `flush_mode` is not needed for normal operation, because end of stream
* detected automatically. You may try to use it for advanced things, but
* this functionality was not tested.
*
* On fail call [[Inflate#onEnd]] with error code and return false.
*
* ##### Example
*
* ```javascript
* push(chunk, false); // push one of data chunks
* ...
* push(chunk, true); // push last chunk
* ```
**/
Inflate.prototype.push = function (data, flush_mode) {
const strm = this.strm
const chunkSize = this.options.chunkSize
const dictionary = this.options.dictionary
let status, _flush_mode, last_avail_out
if (this.ended) return false
if (flush_mode === ~~flush_mode) _flush_mode = flush_mode
else _flush_mode = flush_mode === true ? Z_FINISH : Z_NO_FLUSH
// Convert data if needed
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
for (;;) {
if (strm.avail_out === 0) {
strm.output = new Uint8Array(chunkSize)
strm.next_out = 0
strm.avail_out = chunkSize
}
status = zlib_inflate.inflate(strm, _flush_mode)
if (status === Z_NEED_DICT && dictionary) {
status = zlib_inflate.inflateSetDictionary(strm, dictionary)
if (status === Z_OK) {
status = zlib_inflate.inflate(strm, _flush_mode)
} else if (status === Z_DATA_ERROR) {
// Replace code with more verbose
status = Z_NEED_DICT
}
}
// Skip snyc markers if more data follows and not raw mode
while (
strm.avail_in > 0 &&
status === Z_STREAM_END &&
strm.state.wrap > 0 &&
data[strm.next_in] !== 0
) {
zlib_inflate.inflateReset(strm)
status = zlib_inflate.inflate(strm, _flush_mode)
}
switch (status) {
case Z_STREAM_ERROR:
case Z_DATA_ERROR:
case Z_NEED_DICT:
case Z_MEM_ERROR:
this.onEnd(status)
this.ended = true
return false
}
// Remember real `avail_out` value, because we may patch out buffer content
// to align utf8 strings boundaries.
last_avail_out = strm.avail_out
if (strm.next_out) {
if (strm.avail_out === 0 || status === Z_STREAM_END) {
if (this.options.to === 'string') {
let next_out_utf8 = utf8border(strm.output, strm.next_out)
let tail = strm.next_out - next_out_utf8
let utf8str = buf2string(strm.output, next_out_utf8)
// move tail & realign counters
strm.next_out = tail
strm.avail_out = chunkSize - tail
if (tail)
strm.output.set(
strm.output.subarray(next_out_utf8, next_out_utf8 + tail),
0
)
this.onData(utf8str)
} else {
this.onData(
strm.output.length === strm.next_out
? strm.output
: strm.output.subarray(0, strm.next_out)
)
}
}
}
// Must repeat iteration if out buffer is full
if (status === Z_OK && last_avail_out === 0) continue
// Finalize if end of stream reached.
if (status === Z_STREAM_END) {
status = zlib_inflate.inflateEnd(this.strm)
this.onEnd(status)
this.ended = true
return true
}
if (strm.avail_in === 0) break
}
return true
}
/**
* Inflate#onData(chunk) -> Void
* - chunk (Uint8Array|String): output data. 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). By default - join collected chunks,
* free memory and fill `results` / `err` properties.
**/
Inflate.prototype.onEnd = function (status) {
// On success - join
if (status === Z_OK) {
if (this.options.to === 'string') {
this.result = this.chunks.join('')
} else {
this.result = flattenChunks(this.chunks)
}
}
this.chunks = []
this.err = status
this.msg = this.strm.msg
}
/**
* inflate(data[, options]) -> Uint8Array|String
* - data (Uint8Array|ArrayBuffer): 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
* const pako from 'pako');
* const input = pako.deflate(new Uint8Array([1,2,3,4,5,6,7,8,9]));
* let output;
*
* try {
* output = pako.inflate(input);
* } catch (err) {
* console.log(err);
* }
* ```
**/
function ungzip(input, options) {
const inflator = new Inflate(options)
inflator.push(input)
// That will never happens, if you don't cheat with options :)
if (inflator.err) throw inflator.msg || msg[inflator.err]
return inflator.result
}
/**
* ungzip(data[, options]) -> Uint8Array|String
* - data (Uint8Array|ArrayBuffer): input data to decompress.
* - options (Object): zlib inflate options.
*
* Just shortcut to [[inflate]], because it autodetects format
* by header.content. Done for convenience.
**/
export { ungzip }

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// Join array of chunks to single array.
export function flattenChunks(chunks) {
// calculate data length
let len = 0
for (let i = 0, l = chunks.length; i < l; i++) {
len += chunks[i].length
}
// join chunks
const result = new Uint8Array(len)
for (let i = 0, pos = 0, l = chunks.length; i < l; i++) {
let chunk = chunks[i]
result.set(chunk, pos)
pos += chunk.length
}
return result
}

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// Quick check if we can use fast array to bin string conversion
//
// - apply(Array) can fail on Android 2.2
// - apply(Uint8Array) can fail on iOS 5.1 Safari
//
let STR_APPLY_UIA_OK = true
try {
String.fromCharCode.apply(null, new Uint8Array(1))
} catch (__) {
STR_APPLY_UIA_OK = false
}
// Table with utf8 lengths (calculated by first byte of sequence)
// Note, that 5 & 6-byte values and some 4-byte values can not be represented in JS,
// because max possible codepoint is 0x10ffff
const _utf8len = new Uint8Array(256)
for (let q = 0; q < 256; q++) {
_utf8len[q] =
q >= 252 ? 6 : q >= 248 ? 5 : q >= 240 ? 4 : q >= 224 ? 3 : q >= 192 ? 2 : 1
}
_utf8len[254] = _utf8len[254] = 1 // Invalid sequence start
// convert string to array (typed, when possible)
export const string2buf = str => {
if (typeof TextEncoder === 'function' && TextEncoder.prototype.encode) {
return new TextEncoder().encode(str)
}
let buf,
c,
c2,
m_pos,
i,
str_len = str.length,
buf_len = 0
// count binary size
for (m_pos = 0; m_pos < str_len; m_pos++) {
c = str.charCodeAt(m_pos)
if ((c & 0xfc00) === 0xd800 && m_pos + 1 < str_len) {
c2 = str.charCodeAt(m_pos + 1)
if ((c2 & 0xfc00) === 0xdc00) {
c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00)
m_pos++
}
}
buf_len += c < 0x80 ? 1 : c < 0x800 ? 2 : c < 0x10000 ? 3 : 4
}
// allocate buffer
buf = new Uint8Array(buf_len)
// convert
for (i = 0, m_pos = 0; i < buf_len; m_pos++) {
c = str.charCodeAt(m_pos)
if ((c & 0xfc00) === 0xd800 && m_pos + 1 < str_len) {
c2 = str.charCodeAt(m_pos + 1)
if ((c2 & 0xfc00) === 0xdc00) {
c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00)
m_pos++
}
}
if (c < 0x80) {
/* one byte */
buf[i++] = c
} else if (c < 0x800) {
/* two bytes */
buf[i++] = 0xc0 | (c >>> 6)
buf[i++] = 0x80 | (c & 0x3f)
} else if (c < 0x10000) {
/* three bytes */
buf[i++] = 0xe0 | (c >>> 12)
buf[i++] = 0x80 | ((c >>> 6) & 0x3f)
buf[i++] = 0x80 | (c & 0x3f)
} else {
/* four bytes */
buf[i++] = 0xf0 | (c >>> 18)
buf[i++] = 0x80 | ((c >>> 12) & 0x3f)
buf[i++] = 0x80 | ((c >>> 6) & 0x3f)
buf[i++] = 0x80 | (c & 0x3f)
}
}
return buf
}
// Helper
const buf2binstring = (buf, len) => {
// On Chrome, the arguments in a function call that are allowed is `65534`.
// If the length of the buffer is smaller than that, we can use this optimization,
// otherwise we will take a slower path.
if (len < 65534) {
if (buf.subarray && STR_APPLY_UIA_OK) {
return String.fromCharCode.apply(
null,
buf.length === len ? buf : buf.subarray(0, len)
)
}
}
let result = ''
for (let i = 0; i < len; i++) {
result += String.fromCharCode(buf[i])
}
return result
}
// convert array to string
export const buf2string = (buf, max) => {
const len = max || buf.length
if (typeof TextDecoder === 'function' && TextDecoder.prototype.decode) {
return new TextDecoder().decode(buf.subarray(0, max))
}
let i, out
// Reserve max possible length (2 words per char)
// NB: by unknown reasons, Array is significantly faster for
// String.fromCharCode.apply than Uint16Array.
const utf16buf = new Array(len * 2)
for (out = 0, i = 0; i < len; ) {
let c = buf[i++]
// quick process ascii
if (c < 0x80) {
utf16buf[out++] = c
continue
}
let c_len = _utf8len[c]
// skip 5 & 6 byte codes
if (c_len > 4) {
utf16buf[out++] = 0xfffd
i += c_len - 1
continue
}
// apply mask on first byte
c &= c_len === 2 ? 0x1f : c_len === 3 ? 0x0f : 0x07
// join the rest
while (c_len > 1 && i < len) {
c = (c << 6) | (buf[i++] & 0x3f)
c_len--
}
// terminated by end of string?
if (c_len > 1) {
utf16buf[out++] = 0xfffd
continue
}
if (c < 0x10000) {
utf16buf[out++] = c
} else {
c -= 0x10000
utf16buf[out++] = 0xd800 | ((c >> 10) & 0x3ff)
utf16buf[out++] = 0xdc00 | (c & 0x3ff)
}
}
return buf2binstring(utf16buf, out)
}
// Calculate max possible position in utf8 buffer,
// that will not break sequence. If that's not possible
// - (very small limits) return max size as is.
//
// buf[] - utf8 bytes array
// max - length limit (mandatory);
export const utf8border = (buf, max) => {
max = max || buf.length
if (max > buf.length) {
max = buf.length
}
// go back from last position, until start of sequence found
let pos = max - 1
while (pos >= 0 && (buf[pos] & 0xc0) === 0x80) {
pos--
}
// Very small and broken sequence,
// return max, because we should return something anyway.
if (pos < 0) {
return max
}
// If we came to start of buffer - that means buffer is too small,
// return max too.
if (pos === 0) {
return max
}
return pos + _utf8len[buf[pos]] > max ? pos : max
}

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'use strict'
// Note: adler32 takes 12% for level 0 and 2% for level 6.
// It isn't worth it to make additional optimizations as in original.
// Small size is preferable.
// (C) 1995-2013 Jean-loup Gailly and Mark Adler
// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
const adler32 = (adler, buf, len, pos) => {
let s1 = (adler & 0xffff) | 0,
s2 = ((adler >>> 16) & 0xffff) | 0,
n = 0
while (len !== 0) {
// Set limit ~ twice less than 5552, to keep
// s2 in 31-bits, because we force signed ints.
// in other case %= will fail.
n = len > 2000 ? 2000 : len
len -= n
do {
s1 = (s1 + buf[pos++]) | 0
s2 = (s2 + s1) | 0
} while (--n)
s1 %= 65521
s2 %= 65521
}
return s1 | (s2 << 16) | 0
}
export default adler32

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/* Allowed flush values; see deflate() and inflate() below for details */
export const Z_NO_FLUSH = 0
export const Z_PARTIAL_FLUSH = 1
export const Z_SYNC_FLUSH = 2
export const Z_FULL_FLUSH = 3
export const Z_FINISH = 4
export const Z_BLOCK = 5
export const Z_TREES = 6
/* Return codes for the compression/decompression functions. Negative values
* are errors positive values are used for special but normal events.
*/
export const Z_OK = 0
export const Z_STREAM_END = 1
export const Z_NEED_DICT = 2
export const Z_ERRNO = -1
export const Z_STREAM_ERROR = -2
export const Z_DATA_ERROR = -3
export const Z_MEM_ERROR = -4
export const Z_BUF_ERROR = -5
//Z_VERSION_ERROR = -6
/* compression levels */
export const Z_NO_COMPRESSION = 0
export const Z_BEST_SPEED = 1
export const Z_BEST_COMPRESSION = 9
export const Z_DEFAULT_COMPRESSION = -1
export const Z_FILTERED = 1
export const Z_HUFFMAN_ONLY = 2
export const Z_RLE = 3
export const Z_FIXED = 4
export const Z_DEFAULT_STRATEGY = 0
/* Possible values of the data_type field (though see inflate()) */
export const Z_BINARY = 0
export const Z_TEXT = 1
//Z_ASCII = 1 // = Z_TEXT (deprecated)
export const Z_UNKNOWN = 2
/* The deflate compression method */
export const Z_DEFLATED = 8
//Z_NULL = null // Use -1 or null inline, depending on var type

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'use strict'
// Note: we can't get significant speed boost here.
// So write code to minimize size - no pregenerated tables
// and array tools dependencies.
// (C) 1995-2013 Jean-loup Gailly and Mark Adler
// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
// Use ordinary array, since untyped makes no boost here
const makeTable = () => {
let c,
table = []
for (var n = 0; n < 256; n++) {
c = n
for (var k = 0; k < 8; k++) {
c = c & 1 ? 0xedb88320 ^ (c >>> 1) : c >>> 1
}
table[n] = c
}
return table
}
// Create table on load. Just 255 signed longs. Not a problem.
const crcTable = new Uint32Array(makeTable())
const crc32 = (crc, buf, len, pos) => {
const t = crcTable
const end = pos + len
crc ^= -1
for (let i = pos; i < end; i++) {
crc = (crc >>> 8) ^ t[(crc ^ buf[i]) & 0xff]
}
return crc ^ -1 // >>> 0;
}
export default crc32

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'use strict'
// (C) 1995-2013 Jean-loup Gailly and Mark Adler
// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
function GZheader() {
/* true if compressed data believed to be text */
this.text = 0
/* modification time */
this.time = 0
/* extra flags (not used when writing a gzip file) */
this.xflags = 0
/* operating system */
this.os = 0
/* pointer to extra field or Z_NULL if none */
this.extra = null
/* extra field length (valid if extra != Z_NULL) */
this.extra_len = 0 // Actually, we don't need it in JS,
// but leave for few code modifications
//
// Setup limits is not necessary because in js we should not preallocate memory
// for inflate use constant limit in 65536 bytes
//
/* space at extra (only when reading header) */
// this.extra_max = 0;
/* pointer to zero-terminated file name or Z_NULL */
this.name = ''
/* space at name (only when reading header) */
// this.name_max = 0;
/* pointer to zero-terminated comment or Z_NULL */
this.comment = ''
/* space at comment (only when reading header) */
// this.comm_max = 0;
/* true if there was or will be a header crc */
this.hcrc = 0
/* true when done reading gzip header (not used when writing a gzip file) */
this.done = false
}
export default GZheader

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'use strict'
// (C) 1995-2013 Jean-loup Gailly and Mark Adler
// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
// See state defs from inflate.js
const BAD = 16209 /* got a data error -- remain here until reset */
const TYPE = 16191 /* i: waiting for type bits, including last-flag bit */
/*
Decode literal, length, and distance codes and write out the resulting
literal and match bytes until either not enough input or output is
available, an end-of-block is encountered, or a data error is encountered.
When large enough input and output buffers are supplied to inflate(), for
example, a 16K input buffer and a 64K output buffer, more than 95% of the
inflate execution time is spent in this routine.
Entry assumptions:
state.mode === LEN
strm.avail_in >= 6
strm.avail_out >= 258
start >= strm.avail_out
state.bits < 8
On return, state.mode is one of:
LEN -- ran out of enough output space or enough available input
TYPE -- reached end of block code, inflate() to interpret next block
BAD -- error in block data
Notes:
- The maximum input bits used by a length/distance pair is 15 bits for the
length code, 5 bits for the length extra, 15 bits for the distance code,
and 13 bits for the distance extra. This totals 48 bits, or six bytes.
Therefore if strm.avail_in >= 6, then there is enough input to avoid
checking for available input while decoding.
- The maximum bytes that a single length/distance pair can output is 258
bytes, which is the maximum length that can be coded. inflate_fast()
requires strm.avail_out >= 258 for each loop to avoid checking for
output space.
*/
export default function inflate_fast(strm, start) {
let _in /* local strm.input */
let last /* have enough input while in < last */
let _out /* local strm.output */
let beg /* inflate()'s initial strm.output */
let end /* while out < end, enough space available */
//#ifdef INFLATE_STRICT
let dmax /* maximum distance from zlib header */
//#endif
let wsize /* window size or zero if not using window */
let whave /* valid bytes in the window */
let wnext /* window write index */
// Use `s_window` instead `window`, avoid conflict with instrumentation tools
let s_window /* allocated sliding window, if wsize != 0 */
let hold /* local strm.hold */
let bits /* local strm.bits */
let lcode /* local strm.lencode */
let dcode /* local strm.distcode */
let lmask /* mask for first level of length codes */
let dmask /* mask for first level of distance codes */
let here /* retrieved table entry */
let op /* code bits, operation, extra bits, or */
/* window position, window bytes to copy */
let len /* match length, unused bytes */
let dist /* match distance */
let from /* where to copy match from */
let from_source
let input, output // JS specific, because we have no pointers
/* copy state to local variables */
const state = strm.state
//here = state.here;
_in = strm.next_in
input = strm.input
last = _in + (strm.avail_in - 5)
_out = strm.next_out
output = strm.output
beg = _out - (start - strm.avail_out)
end = _out + (strm.avail_out - 257)
//#ifdef INFLATE_STRICT
dmax = state.dmax
//#endif
wsize = state.wsize
whave = state.whave
wnext = state.wnext
s_window = state.window
hold = state.hold
bits = state.bits
lcode = state.lencode
dcode = state.distcode
lmask = (1 << state.lenbits) - 1
dmask = (1 << state.distbits) - 1
/* decode literals and length/distances until end-of-block or not enough
input data or output space */
top: do {
if (bits < 15) {
hold += input[_in++] << bits
bits += 8
hold += input[_in++] << bits
bits += 8
}
here = lcode[hold & lmask]
dolen: for (;;) {
// Goto emulation
op = here >>> 24 /*here.bits*/
hold >>>= op
bits -= op
op = (here >>> 16) & 0xff /*here.op*/
if (op === 0) {
/* literal */
//Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
// "inflate: literal '%c'\n" :
// "inflate: literal 0x%02x\n", here.val));
output[_out++] = here & 0xffff /*here.val*/
} else if (op & 16) {
/* length base */
len = here & 0xffff /*here.val*/
op &= 15 /* number of extra bits */
if (op) {
if (bits < op) {
hold += input[_in++] << bits
bits += 8
}
len += hold & ((1 << op) - 1)
hold >>>= op
bits -= op
}
//Tracevv((stderr, "inflate: length %u\n", len));
if (bits < 15) {
hold += input[_in++] << bits
bits += 8
hold += input[_in++] << bits
bits += 8
}
here = dcode[hold & dmask]
dodist: for (;;) {
// goto emulation
op = here >>> 24 /*here.bits*/
hold >>>= op
bits -= op
op = (here >>> 16) & 0xff /*here.op*/
if (op & 16) {
/* distance base */
dist = here & 0xffff /*here.val*/
op &= 15 /* number of extra bits */
if (bits < op) {
hold += input[_in++] << bits
bits += 8
if (bits < op) {
hold += input[_in++] << bits
bits += 8
}
}
dist += hold & ((1 << op) - 1)
//#ifdef INFLATE_STRICT
if (dist > dmax) {
strm.msg = 'invalid distance too far back'
state.mode = BAD
break top
}
//#endif
hold >>>= op
bits -= op
//Tracevv((stderr, "inflate: distance %u\n", dist));
op = _out - beg /* max distance in output */
if (dist > op) {
/* see if copy from window */
op = dist - op /* distance back in window */
if (op > whave) {
if (state.sane) {
strm.msg = 'invalid distance too far back'
state.mode = BAD
break top
}
// (!) This block is disabled in zlib defaults,
// don't enable it for binary compatibility
//#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
// if (len <= op - whave) {
// do {
// output[_out++] = 0;
// } while (--len);
// continue top;
// }
// len -= op - whave;
// do {
// output[_out++] = 0;
// } while (--op > whave);
// if (op === 0) {
// from = _out - dist;
// do {
// output[_out++] = output[from++];
// } while (--len);
// continue top;
// }
//#endif
}
from = 0 // window index
from_source = s_window
if (wnext === 0) {
/* very common case */
from += wsize - op
if (op < len) {
/* some from window */
len -= op
do {
output[_out++] = s_window[from++]
} while (--op)
from = _out - dist /* rest from output */
from_source = output
}
} else if (wnext < op) {
/* wrap around window */
from += wsize + wnext - op
op -= wnext
if (op < len) {
/* some from end of window */
len -= op
do {
output[_out++] = s_window[from++]
} while (--op)
from = 0
if (wnext < len) {
/* some from start of window */
op = wnext
len -= op
do {
output[_out++] = s_window[from++]
} while (--op)
from = _out - dist /* rest from output */
from_source = output
}
}
} else {
/* contiguous in window */
from += wnext - op
if (op < len) {
/* some from window */
len -= op
do {
output[_out++] = s_window[from++]
} while (--op)
from = _out - dist /* rest from output */
from_source = output
}
}
while (len > 2) {
output[_out++] = from_source[from++]
output[_out++] = from_source[from++]
output[_out++] = from_source[from++]
len -= 3
}
if (len) {
output[_out++] = from_source[from++]
if (len > 1) {
output[_out++] = from_source[from++]
}
}
} else {
from = _out - dist /* copy direct from output */
do {
/* minimum length is three */
output[_out++] = output[from++]
output[_out++] = output[from++]
output[_out++] = output[from++]
len -= 3
} while (len > 2)
if (len) {
output[_out++] = output[from++]
if (len > 1) {
output[_out++] = output[from++]
}
}
}
} else if ((op & 64) === 0) {
/* 2nd level distance code */
here =
dcode[(here & 0xffff) /*here.val*/ + (hold & ((1 << op) - 1))]
continue dodist
} else {
strm.msg = 'invalid distance code'
state.mode = BAD
break top
}
break // need to emulate goto via "continue"
}
} else if ((op & 64) === 0) {
/* 2nd level length code */
here = lcode[(here & 0xffff) /*here.val*/ + (hold & ((1 << op) - 1))]
continue dolen
} else if (op & 32) {
/* end-of-block */
//Tracevv((stderr, "inflate: end of block\n"));
state.mode = TYPE
break top
} else {
strm.msg = 'invalid literal/length code'
state.mode = BAD
break top
}
break // need to emulate goto via "continue"
}
} while (_in < last && _out < end)
/* return unused bytes (on entry, bits < 8, so in won't go too far back) */
len = bits >> 3
_in -= len
bits -= len << 3
hold &= (1 << bits) - 1
/* update state and return */
strm.next_in = _in
strm.next_out = _out
strm.avail_in = _in < last ? 5 + (last - _in) : 5 - (_in - last)
strm.avail_out = _out < end ? 257 + (end - _out) : 257 - (_out - end)
state.hold = hold
state.bits = bits
return
}

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'use strict'
// (C) 1995-2013 Jean-loup Gailly and Mark Adler
// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
const MAXBITS = 15
const ENOUGH_LENS = 852
const ENOUGH_DISTS = 592
//const ENOUGH = (ENOUGH_LENS+ENOUGH_DISTS);
const CODES = 0
const LENS = 1
const DISTS = 2
const lbase = new Uint16Array([
/* Length codes 257..285 base */ 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19,
23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0
])
const lext = new Uint8Array([
/* Length codes 257..285 extra */ 16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17,
17, 18, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 72, 78
])
const dbase = new Uint16Array([
/* Distance codes 0..29 base */ 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65,
97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193,
12289, 16385, 24577, 0, 0
])
const dext = new Uint8Array([
/* Distance codes 0..29 extra */ 16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20,
20, 21, 21, 22, 22, 23, 23, 24, 24, 25, 25, 26, 26, 27, 27, 28, 28, 29, 29,
64, 64
])
const inflate_table = (
type,
lens,
lens_index,
codes,
table,
table_index,
work,
opts
) => {
const bits = opts.bits
//here = opts.here; /* table entry for duplication */
let len = 0 /* a code's length in bits */
let sym = 0 /* index of code symbols */
let min = 0,
max = 0 /* minimum and maximum code lengths */
let root = 0 /* number of index bits for root table */
let curr = 0 /* number of index bits for current table */
let drop = 0 /* code bits to drop for sub-table */
let left = 0 /* number of prefix codes available */
let used = 0 /* code entries in table used */
let huff = 0 /* Huffman code */
let incr /* for incrementing code, index */
let fill /* index for replicating entries */
let low /* low bits for current root entry */
let mask /* mask for low root bits */
let next /* next available space in table */
let base = null /* base value table to use */
// let shoextra; /* extra bits table to use */
let match /* use base and extra for symbol >= match */
const count = new Uint16Array(MAXBITS + 1) //[MAXBITS+1]; /* number of codes of each length */
const offs = new Uint16Array(MAXBITS + 1) //[MAXBITS+1]; /* offsets in table for each length */
let extra = null
let here_bits, here_op, here_val
/*
Process a set of code lengths to create a canonical Huffman code. The
code lengths are lens[0..codes-1]. Each length corresponds to the
symbols 0..codes-1. The Huffman code is generated by first sorting the
symbols by length from short to long, and retaining the symbol order
for codes with equal lengths. Then the code starts with all zero bits
for the first code of the shortest length, and the codes are integer
increments for the same length, and zeros are appended as the length
increases. For the deflate format, these bits are stored backwards
from their more natural integer increment ordering, and so when the
decoding tables are built in the large loop below, the integer codes
are incremented backwards.
This routine assumes, but does not check, that all of the entries in
lens[] are in the range 0..MAXBITS. The caller must assure this.
1..MAXBITS is interpreted as that code length. zero means that that
symbol does not occur in this code.
The codes are sorted by computing a count of codes for each length,
creating from that a table of starting indices for each length in the
sorted table, and then entering the symbols in order in the sorted
table. The sorted table is work[], with that space being provided by
the caller.
The length counts are used for other purposes as well, i.e. finding
the minimum and maximum length codes, determining if there are any
codes at all, checking for a valid set of lengths, and looking ahead
at length counts to determine sub-table sizes when building the
decoding tables.
*/
/* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
for (len = 0; len <= MAXBITS; len++) {
count[len] = 0
}
for (sym = 0; sym < codes; sym++) {
count[lens[lens_index + sym]]++
}
/* bound code lengths, force root to be within code lengths */
root = bits
for (max = MAXBITS; max >= 1; max--) {
if (count[max] !== 0) {
break
}
}
if (root > max) {
root = max
}
if (max === 0) {
/* no symbols to code at all */
//table.op[opts.table_index] = 64; //here.op = (var char)64; /* invalid code marker */
//table.bits[opts.table_index] = 1; //here.bits = (var char)1;
//table.val[opts.table_index++] = 0; //here.val = (var short)0;
table[table_index++] = (1 << 24) | (64 << 16) | 0
//table.op[opts.table_index] = 64;
//table.bits[opts.table_index] = 1;
//table.val[opts.table_index++] = 0;
table[table_index++] = (1 << 24) | (64 << 16) | 0
opts.bits = 1
return 0 /* no symbols, but wait for decoding to report error */
}
for (min = 1; min < max; min++) {
if (count[min] !== 0) {
break
}
}
if (root < min) {
root = min
}
/* check for an over-subscribed or incomplete set of lengths */
left = 1
for (len = 1; len <= MAXBITS; len++) {
left <<= 1
left -= count[len]
if (left < 0) {
return -1
} /* over-subscribed */
}
if (left > 0 && (type === CODES || max !== 1)) {
return -1 /* incomplete set */
}
/* generate offsets into symbol table for each length for sorting */
offs[1] = 0
for (len = 1; len < MAXBITS; len++) {
offs[len + 1] = offs[len] + count[len]
}
/* sort symbols by length, by symbol order within each length */
for (sym = 0; sym < codes; sym++) {
if (lens[lens_index + sym] !== 0) {
work[offs[lens[lens_index + sym]]++] = sym
}
}
/*
Create and fill in decoding tables. In this loop, the table being
filled is at next and has curr index bits. The code being used is huff
with length len. That code is converted to an index by dropping drop
bits off of the bottom. For codes where len is less than drop + curr,
those top drop + curr - len bits are incremented through all values to
fill the table with replicated entries.
root is the number of index bits for the root table. When len exceeds
root, sub-tables are created pointed to by the root entry with an index
of the low root bits of huff. This is saved in low to check for when a
new sub-table should be started. drop is zero when the root table is
being filled, and drop is root when sub-tables are being filled.
When a new sub-table is needed, it is necessary to look ahead in the
code lengths to determine what size sub-table is needed. The length
counts are used for this, and so count[] is decremented as codes are
entered in the tables.
used keeps track of how many table entries have been allocated from the
provided *table space. It is checked for LENS and DIST tables against
the constants ENOUGH_LENS and ENOUGH_DISTS to guard against changes in
the initial root table size constants. See the comments in inftrees.h
for more information.
sym increments through all symbols, and the loop terminates when
all codes of length max, i.e. all codes, have been processed. This
routine permits incomplete codes, so another loop after this one fills
in the rest of the decoding tables with invalid code markers.
*/
/* set up for code type */
// poor man optimization - use if-else instead of switch,
// to avoid deopts in old v8
if (type === CODES) {
base = extra = work /* dummy value--not used */
match = 20
} else if (type === LENS) {
base = lbase
extra = lext
match = 257
} else {
/* DISTS */
base = dbase
extra = dext
match = 0
}
/* initialize opts for loop */
huff = 0 /* starting code */
sym = 0 /* starting code symbol */
len = min /* starting code length */
next = table_index /* current table to fill in */
curr = root /* current table index bits */
drop = 0 /* current bits to drop from code for index */
low = -1 /* trigger new sub-table when len > root */
used = 1 << root /* use root table entries */
mask = used - 1 /* mask for comparing low */
/* check available table space */
if (
(type === LENS && used > ENOUGH_LENS) ||
(type === DISTS && used > ENOUGH_DISTS)
) {
return 1
}
/* process all codes and make table entries */
for (;;) {
/* create table entry */
here_bits = len - drop
if (work[sym] + 1 < match) {
here_op = 0
here_val = work[sym]
} else if (work[sym] >= match) {
here_op = extra[work[sym] - match]
here_val = base[work[sym] - match]
} else {
here_op = 32 + 64 /* end of block */
here_val = 0
}
/* replicate for those indices with low len bits equal to huff */
incr = 1 << (len - drop)
fill = 1 << curr
min = fill /* save offset to next table */
do {
fill -= incr
table[next + (huff >> drop) + fill] =
(here_bits << 24) | (here_op << 16) | here_val | 0
} while (fill !== 0)
/* backwards increment the len-bit code huff */
incr = 1 << (len - 1)
while (huff & incr) {
incr >>= 1
}
if (incr !== 0) {
huff &= incr - 1
huff += incr
} else {
huff = 0
}
/* go to next symbol, update count, len */
sym++
if (--count[len] === 0) {
if (len === max) {
break
}
len = lens[lens_index + work[sym]]
}
/* create new sub-table if needed */
if (len > root && (huff & mask) !== low) {
/* if first time, transition to sub-tables */
if (drop === 0) {
drop = root
}
/* increment past last table */
next += min /* here min is 1 << curr */
/* determine length of next table */
curr = len - drop
left = 1 << curr
while (curr + drop < max) {
left -= count[curr + drop]
if (left <= 0) {
break
}
curr++
left <<= 1
}
/* check for enough space */
used += 1 << curr
if (
(type === LENS && used > ENOUGH_LENS) ||
(type === DISTS && used > ENOUGH_DISTS)
) {
return 1
}
/* point entry in root table to sub-table */
low = huff & mask
/*table.op[low] = curr;
table.bits[low] = root;
table.val[low] = next - opts.table_index;*/
table[low] = (root << 24) | (curr << 16) | (next - table_index) | 0
}
}
/* fill in remaining table entry if code is incomplete (guaranteed to have
at most one remaining entry, since if the code is incomplete, the
maximum code length that was allowed to get this far is one bit) */
if (huff !== 0) {
//table.op[next + huff] = 64; /* invalid code marker */
//table.bits[next + huff] = len - drop;
//table.val[next + huff] = 0;
table[next + huff] = ((len - drop) << 24) | (64 << 16) | 0
}
/* set return parameters */
//opts.table_index += used;
opts.bits = root
return 0
}
export default inflate_table

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'use strict'
// (C) 1995-2013 Jean-loup Gailly and Mark Adler
// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
export default {
2: 'need dictionary' /* Z_NEED_DICT 2 */,
1: 'stream end' /* Z_STREAM_END 1 */,
0: '' /* Z_OK 0 */,
'-1': 'file error' /* Z_ERRNO (-1) */,
'-2': 'stream error' /* Z_STREAM_ERROR (-2) */,
'-3': 'data error' /* Z_DATA_ERROR (-3) */,
'-4': 'insufficient memory' /* Z_MEM_ERROR (-4) */,
'-5': 'buffer error' /* Z_BUF_ERROR (-5) */,
'-6': 'incompatible version' /* Z_VERSION_ERROR (-6) */
}

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'use strict'
// (C) 1995-2013 Jean-loup Gailly and Mark Adler
// (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
export default function ZStream() {
/* next input byte */
this.input = null // JS specific, because we have no pointers
this.next_in = 0
/* number of bytes available at input */
this.avail_in = 0
/* total number of input bytes read so far */
this.total_in = 0
/* next output byte should be put there */
this.output = null // JS specific, because we have no pointers
this.next_out = 0
/* remaining free space at output */
this.avail_out = 0
/* total number of bytes output so far */
this.total_out = 0
/* last error message, NULL if no error */
this.msg = '' /*Z_NULL*/
/* not visible by applications */
this.state = null
/* best guess about the data type: binary or text */
this.data_type = 2 /*Z_UNKNOWN*/
/* adler32 value of the uncompressed data */
this.adler = 0
}

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{
"name": "@bytedo/gzip",
"type": "module",
"description": "zlib port to javascript - fast, modularized, with browser support",
"version": "2.1.0",
"keywords": [
"zlib",
"deflate",
"inflate",
"gzip"
],
"files": [
"dist/*"
],
"license": "(MIT AND Zlib)",
"repository": "bytedo/gzip",
"scripts": {
"build": "esbuild index.js --minify --bundle --format=esm --target=esnext --outfile=dist/index.js"
},
"devDependencies": {
"esbuild": "^0.17.16"
}
}