addon-sdk/source/lib/sdk/io/byte-streams.js@6474c204b198 (annotated)
addon-sdk/source/lib/sdk/io/byte-streams.js
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 2 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 3 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 4 | |
| michael@0 | 5 | "use strict"; |
| michael@0 | 6 | |
| michael@0 | 7 | module.metadata = { |
| michael@0 | 8 | "stability": "experimental" |
| michael@0 | 9 | }; |
| michael@0 | 10 | |
| michael@0 | 11 | exports.ByteReader = ByteReader; |
| michael@0 | 12 | exports.ByteWriter = ByteWriter; |
| michael@0 | 13 | |
| michael@0 | 14 | const {Cc, Ci} = require("chrome"); |
| michael@0 | 15 | |
| michael@0 | 16 | // This just controls the maximum number of bytes we read in at one time. |
| michael@0 | 17 | const BUFFER_BYTE_LEN = 0x8000; |
| michael@0 | 18 | |
| michael@0 | 19 | function ByteReader(inputStream) { |
| michael@0 | 20 | const self = this; |
| michael@0 | 21 | |
| michael@0 | 22 | let stream = Cc["@mozilla.org/binaryinputstream;1"]. |
| michael@0 | 23 | createInstance(Ci.nsIBinaryInputStream); |
| michael@0 | 24 | stream.setInputStream(inputStream); |
| michael@0 | 25 | |
| michael@0 | 26 | let manager = new StreamManager(this, stream); |
| michael@0 | 27 | |
| michael@0 | 28 | this.read = function ByteReader_read(numBytes) { |
| michael@0 | 29 | manager.ensureOpened(); |
| michael@0 | 30 | if (typeof(numBytes) !== "number") |
| michael@0 | 31 | numBytes = Infinity; |
| michael@0 | 32 | |
| michael@0 | 33 | let data = ""; |
| michael@0 | 34 | let read = 0; |
| michael@0 | 35 | try { |
| michael@0 | 36 | while (true) { |
| michael@0 | 37 | let avail = stream.available(); |
| michael@0 | 38 | let toRead = Math.min(numBytes - read, avail, BUFFER_BYTE_LEN); |
| michael@0 | 39 | if (toRead <= 0) |
| michael@0 | 40 | break; |
| michael@0 | 41 | data += stream.readBytes(toRead); |
| michael@0 | 42 | read += toRead; |
| michael@0 | 43 | } |
| michael@0 | 44 | } |
| michael@0 | 45 | catch (err) { |
| michael@0 | 46 | throw new Error("Error reading from stream: " + err); |
| michael@0 | 47 | } |
| michael@0 | 48 | |
| michael@0 | 49 | return data; |
| michael@0 | 50 | }; |
| michael@0 | 51 | } |
| michael@0 | 52 | |
| michael@0 | 53 | function ByteWriter(outputStream) { |
| michael@0 | 54 | const self = this; |
| michael@0 | 55 | |
| michael@0 | 56 | let stream = Cc["@mozilla.org/binaryoutputstream;1"]. |
| michael@0 | 57 | createInstance(Ci.nsIBinaryOutputStream); |
| michael@0 | 58 | stream.setOutputStream(outputStream); |
| michael@0 | 59 | |
| michael@0 | 60 | let manager = new StreamManager(this, stream); |
| michael@0 | 61 | |
| michael@0 | 62 | this.write = function ByteWriter_write(str) { |
| michael@0 | 63 | manager.ensureOpened(); |
| michael@0 | 64 | try { |
| michael@0 | 65 | stream.writeBytes(str, str.length); |
| michael@0 | 66 | } |
| michael@0 | 67 | catch (err) { |
| michael@0 | 68 | throw new Error("Error writing to stream: " + err); |
| michael@0 | 69 | } |
| michael@0 | 70 | }; |
| michael@0 | 71 | } |
| michael@0 | 72 | |
| michael@0 | 73 | |
| michael@0 | 74 | // This manages the lifetime of stream, a ByteReader or ByteWriter. It defines |
| michael@0 | 75 | // closed and close() on stream and registers an unload listener that closes |
| michael@0 | 76 | // rawStream if it's still opened. It also provides ensureOpened(), which |
| michael@0 | 77 | // throws an exception if the stream is closed. |
| michael@0 | 78 | function StreamManager(stream, rawStream) { |
| michael@0 | 79 | const self = this; |
| michael@0 | 80 | this.rawStream = rawStream; |
| michael@0 | 81 | this.opened = true; |
| michael@0 | 82 | |
| michael@0 | 83 | stream.__defineGetter__("closed", function stream_closed() { |
| michael@0 | 84 | return !self.opened; |
| michael@0 | 85 | }); |
| michael@0 | 86 | |
| michael@0 | 87 | stream.close = function stream_close() { |
| michael@0 | 88 | self.ensureOpened(); |
| michael@0 | 89 | self.unload(); |
| michael@0 | 90 | }; |
| michael@0 | 91 | |
| michael@0 | 92 | require("../system/unload").ensure(this); |
| michael@0 | 93 | } |
| michael@0 | 94 | |
| michael@0 | 95 | StreamManager.prototype = { |
| michael@0 | 96 | ensureOpened: function StreamManager_ensureOpened() { |
| michael@0 | 97 | if (!this.opened) |
| michael@0 | 98 | throw new Error("The stream is closed and cannot be used."); |
| michael@0 | 99 | }, |
| michael@0 | 100 | unload: function StreamManager_unload() { |
| michael@0 | 101 | this.rawStream.close(); |
| michael@0 | 102 | this.opened = false; |
| michael@0 | 103 | } |
| michael@0 | 104 | }; |
