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std/node/_zlib_binding.mjs

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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// Copyright (c) 2014-2015 Devon Govett <devongovett@gmail.com>// Forked from https://github.com/browserify/browserify-zlib
// deno-lint-ignore-file
import assert from "./assert.ts";import { constants, zlib_deflate, zlib_inflate, Zstream } from "./_pako.mjs";
export const Z_NO_FLUSH = constants.Z_NO_FLUSH;export const Z_PARTIAL_FLUSH = constants.Z_PARTIAL_FLUSH;export const Z_SYNC_FLUSH = constants.Z_SYNC_FLUSH;export const Z_FULL_FLUSH = constants.Z_FULL_FLUSH;export const Z_FINISH = constants.Z_FINISH;export const Z_BLOCK = constants.Z_BLOCK;export const Z_TREES = constants.Z_TREES;export const Z_OK = constants.Z_OK;export const Z_STREAM_END = constants.Z_STREAM_END;export const Z_NEED_DICT = constants.Z_NEED_DICT;export const Z_ERRNO = constants.Z_ERRNO;export const Z_STREAM_ERROR = constants.Z_STREAM_ERROR;export const Z_DATA_ERROR = constants.Z_DATA_ERROR;export const Z_MEM_ERROR = constants.Z_MEM_ERROR;export const Z_BUF_ERROR = constants.Z_BUF_ERROR;export const Z_VERSION_ERROR = constants.Z_VERSION_ERROR;export const Z_NO_COMPRESSION = constants.Z_NO_COMPRESSION;export const Z_BEST_SPEED = constants.Z_BEST_SPEED;export const Z_BEST_COMPRESSION = constants.Z_BEST_COMPRESSION;export const Z_DEFAULT_COMPRESSION = constants.Z_DEFAULT_COMPRESSION;export const Z_FILTERED = constants.Z_FILTERED;export const Z_HUFFMAN_ONLY = constants.Z_HUFFMAN_ONLYZ_FILTERED;export const Z_RLE = constants.Z_RLE;export const Z_FIXED = constants.Z_FIXED;export const Z_DEFAULT_STRATEGY = constants.Z_DEFAULT_STRATEGY;export const Z_BINARY = constants.Z_BINARY;export const Z_TEXT = constants.Z_TEXT;export const Z_UNKNOWN = constants.Z_UNKNOWN;export const Z_DEFLATED = constants.Z_DEFLATED;
// zlib modesexport const NONE = 0;export const DEFLATE = 1;export const INFLATE = 2;export const GZIP = 3;export const GUNZIP = 4;export const DEFLATERAW = 5;export const INFLATERAW = 6;export const UNZIP = 7;
var GZIP_HEADER_ID1 = 0x1f;var GZIP_HEADER_ID2 = 0x8b;
/** * Emulate Node's zlib C++ layer for use by the JS layer in index.js */function Zlib(mode) { if (typeof mode !== "number" || mode < DEFLATE || mode > UNZIP) { throw new TypeError("Bad argument"); }
this.dictionary = null; this.err = 0; this.flush = 0; this.init_done = false; this.level = 0; this.memLevel = 0; this.mode = mode; this.strategy = 0; this.windowBits = 0; this.write_in_progress = false; this.pending_close = false; this.gzip_id_bytes_read = 0;}
Zlib.prototype.close = function () { if (this.write_in_progress) { this.pending_close = true; return; }
this.pending_close = false;
assert(this.init_done, "close before init"); assert(this.mode <= UNZIP);
if (this.mode === DEFLATE || this.mode === GZIP || this.mode === DEFLATERAW) { zlib_deflate.deflateEnd(this.strm); } else if ( this.mode === INFLATE || this.mode === GUNZIP || this.mode === INFLATERAW || this.mode === UNZIP ) { zlib_inflate.inflateEnd(this.strm); }
this.mode = NONE;
this.dictionary = null;};
Zlib.prototype.write = function ( flush, input, in_off, in_len, out, out_off, out_len,) { return this._write(true, flush, input, in_off, in_len, out, out_off, out_len);};
Zlib.prototype.writeSync = function ( flush, input, in_off, in_len, out, out_off, out_len,) { return this._write( false, flush, input, in_off, in_len, out, out_off, out_len, );};
Zlib.prototype._write = function ( async, flush, input, in_off, in_len, out, out_off, out_len,) { assert.equal(arguments.length, 8);
assert(this.init_done, "write before init"); assert(this.mode !== NONE, "already finalized"); assert.equal(false, this.write_in_progress, "write already in progress"); assert.equal(false, this.pending_close, "close is pending");
this.write_in_progress = true;
assert.equal(false, flush === undefined, "must provide flush value");
this.write_in_progress = true;
if ( flush !== Z_NO_FLUSH && flush !== Z_PARTIAL_FLUSH && flush !== Z_SYNC_FLUSH && flush !== Z_FULL_FLUSH && flush !== Z_FINISH && flush !== Z_BLOCK ) { throw new Error("Invalid flush value"); }
if (input == null) { input = Buffer.alloc(0); in_len = 0; in_off = 0; }
this.strm.avail_in = in_len; this.strm.input = input; this.strm.next_in = in_off; this.strm.avail_out = out_len; this.strm.output = out; this.strm.next_out = out_off; this.flush = flush;
if (!async) { // sync version this._process();
if (this._checkError()) { return this._afterSync(); } return; }
// async version var self = this; process.nextTick(function () { self._process(); self._after(); });
return this;};
Zlib.prototype._afterSync = function () { var avail_out = this.strm.avail_out; var avail_in = this.strm.avail_in;
this.write_in_progress = false;
return [avail_in, avail_out];};
Zlib.prototype._process = function () { var next_expected_header_byte = null;
// If the avail_out is left at 0, then it means that it ran out // of room. If there was avail_out left over, then it means // that all of the input was consumed. switch (this.mode) { case DEFLATE: case GZIP: case DEFLATERAW: this.err = zlib_deflate.deflate(this.strm, this.flush); break; case UNZIP: if (this.strm.avail_in > 0) { next_expected_header_byte = this.strm.next_in; }
switch (this.gzip_id_bytes_read) { case 0: if (next_expected_header_byte === null) { break; }
if (this.strm.input[next_expected_header_byte] === GZIP_HEADER_ID1) { this.gzip_id_bytes_read = 1; next_expected_header_byte++;
if (this.strm.avail_in === 1) { // The only available byte was already read. break; } } else { this.mode = INFLATE; break; }
// fallthrough
case 1: if (next_expected_header_byte === null) { break; }
if (this.strm.input[next_expected_header_byte] === GZIP_HEADER_ID2) { this.gzip_id_bytes_read = 2; this.mode = GUNZIP; } else { // There is no actual difference between INFLATE and INFLATERAW // (after initialization). this.mode = INFLATE; }
break; default: throw new Error("invalid number of gzip magic number bytes read"); }
// fallthrough
case INFLATE: case GUNZIP: case INFLATERAW: this.err = zlib_inflate.inflate(this.strm, this.flush);
// If data was encoded with dictionary if (this.err === Z_NEED_DICT && this.dictionary) { // Load it this.err = zlib_inflate.inflateSetDictionary( this.strm, this.dictionary, ); if (this.err === Z_OK) { // And try to decode again this.err = zlib_inflate.inflate(this.strm, this.flush); } else if (this.err === Z_DATA_ERROR) { // Both inflateSetDictionary() and inflate() return Z_DATA_ERROR. // Make it possible for After() to tell a bad dictionary from bad // input. this.err = Z_NEED_DICT; } } while ( this.strm.avail_in > 0 && this.mode === GUNZIP && this.err === Z_STREAM_END && this.strm.next_in[0] !== 0x00 ) { // Bytes remain in input buffer. Perhaps this is another compressed // member in the same archive, or just trailing garbage. // Trailing zero bytes are okay, though, since they are frequently // used for padding.
this.reset(); this.err = zlib_inflate.inflate(this.strm, this.flush); } break; default: throw new Error("Unknown mode " + this.mode); }};
Zlib.prototype._checkError = function () { // Acceptable error states depend on the type of zlib stream. switch (this.err) { case Z_OK: case Z_BUF_ERROR: if (this.strm.avail_out !== 0 && this.flush === Z_FINISH) { this._error("unexpected end of file"); return false; } break; case Z_STREAM_END: // normal statuses, not fatal break; case Z_NEED_DICT: if (this.dictionary == null) { this._error("Missing dictionary"); } else { this._error("Bad dictionary"); } return false; default: // something else. this._error("Zlib error"); return false; }
return true;};
Zlib.prototype._after = function () { if (!this._checkError()) { return; }
var avail_out = this.strm.avail_out; var avail_in = this.strm.avail_in;
this.write_in_progress = false;
// call the write() cb this.callback(avail_in, avail_out);
if (this.pending_close) { this.close(); }};
Zlib.prototype._error = function (message) { if (this.strm.msg) { message = this.strm.msg; } this.onerror(message, this.err);
// no hope of rescue. this.write_in_progress = false; if (this.pending_close) { this.close(); }};
Zlib.prototype.init = function ( windowBits, level, memLevel, strategy, dictionary,) { assert( arguments.length === 4 || arguments.length === 5, "init(windowBits, level, memLevel, strategy, [dictionary])", );
assert(windowBits >= 8 && windowBits <= 15, "invalid windowBits"); assert(level >= -1 && level <= 9, "invalid compression level");
assert(memLevel >= 1 && memLevel <= 9, "invalid memlevel");
assert( strategy === Z_FILTERED || strategy === Z_HUFFMAN_ONLY || strategy === Z_RLE || strategy === Z_FIXED || strategy === Z_DEFAULT_STRATEGY, "invalid strategy", );
this._init(level, windowBits, memLevel, strategy, dictionary); this._setDictionary();};
Zlib.prototype.params = function () { throw new Error("deflateParams Not supported");};
Zlib.prototype.reset = function () { this._reset(); this._setDictionary();};
Zlib.prototype._init = function ( level, windowBits, memLevel, strategy, dictionary,) { this.level = level; this.windowBits = windowBits; this.memLevel = memLevel; this.strategy = strategy;
this.flush = Z_NO_FLUSH;
this.err = Z_OK;
if (this.mode === GZIP || this.mode === GUNZIP) { this.windowBits += 16; }
if (this.mode === UNZIP) { this.windowBits += 32; }
if (this.mode === DEFLATERAW || this.mode === INFLATERAW) { this.windowBits = -1 * this.windowBits; }
this.strm = new Zstream();
switch (this.mode) { case DEFLATE: case GZIP: case DEFLATERAW: this.err = zlib_deflate.deflateInit2( this.strm, this.level, Z_DEFLATED, this.windowBits, this.memLevel, this.strategy, ); break; case INFLATE: case GUNZIP: case INFLATERAW: case UNZIP: this.err = zlib_inflate.inflateInit2(this.strm, this.windowBits); break; default: throw new Error("Unknown mode " + this.mode); }
if (this.err !== Z_OK) { this._error("Init error"); }
this.dictionary = dictionary;
this.write_in_progress = false; this.init_done = true;};
Zlib.prototype._setDictionary = function () { if (this.dictionary == null) { return; }
this.err = Z_OK;
switch (this.mode) { case DEFLATE: case DEFLATERAW: this.err = zlib_deflate.deflateSetDictionary(this.strm, this.dictionary); break; default: break; }
if (this.err !== Z_OK) { this._error("Failed to set dictionary"); }};
Zlib.prototype._reset = function () { this.err = Z_OK;
switch (this.mode) { case DEFLATE: case DEFLATERAW: case GZIP: this.err = zlib_deflate.deflateReset(this.strm); break; case INFLATE: case INFLATERAW: case GUNZIP: this.err = zlib_inflate.inflateReset(this.strm); break; default: break; }
if (this.err !== Z_OK) { this._error("Failed to reset stream"); }};
export { Zlib };