The Tor Browser / file comparison
comparison: addon-sdk/source/lib/sdk/io/byte-streams.js
addon-sdk/source/lib/sdk/io/byte-streams.js
- changeset 0
- 6474c204b198
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| -1:000000000000 | 0:5dead0c8cda6 |
|---|---|
| 1 /* This Source Code Form is subject to the terms of the Mozilla Public | |
| 2 * License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ | |
| 4 | |
| 5 "use strict"; | |
| 6 | |
| 7 module.metadata = { | |
| 8 "stability": "experimental" | |
| 9 }; | |
| 10 | |
| 11 exports.ByteReader = ByteReader; | |
| 12 exports.ByteWriter = ByteWriter; | |
| 13 | |
| 14 const {Cc, Ci} = require("chrome"); | |
| 15 | |
| 16 // This just controls the maximum number of bytes we read in at one time. | |
| 17 const BUFFER_BYTE_LEN = 0x8000; | |
| 18 | |
| 19 function ByteReader(inputStream) { | |
| 20 const self = this; | |
| 21 | |
| 22 let stream = Cc["@mozilla.org/binaryinputstream;1"]. | |
| 23 createInstance(Ci.nsIBinaryInputStream); | |
| 24 stream.setInputStream(inputStream); | |
| 25 | |
| 26 let manager = new StreamManager(this, stream); | |
| 27 | |
| 28 this.read = function ByteReader_read(numBytes) { | |
| 29 manager.ensureOpened(); | |
| 30 if (typeof(numBytes) !== "number") | |
| 31 numBytes = Infinity; | |
| 32 | |
| 33 let data = ""; | |
| 34 let read = 0; | |
| 35 try { | |
| 36 while (true) { | |
| 37 let avail = stream.available(); | |
| 38 let toRead = Math.min(numBytes - read, avail, BUFFER_BYTE_LEN); | |
| 39 if (toRead <= 0) | |
| 40 break; | |
| 41 data += stream.readBytes(toRead); | |
| 42 read += toRead; | |
| 43 } | |
| 44 } | |
| 45 catch (err) { | |
| 46 throw new Error("Error reading from stream: " + err); | |
| 47 } | |
| 48 | |
| 49 return data; | |
| 50 }; | |
| 51 } | |
| 52 | |
| 53 function ByteWriter(outputStream) { | |
| 54 const self = this; | |
| 55 | |
| 56 let stream = Cc["@mozilla.org/binaryoutputstream;1"]. | |
| 57 createInstance(Ci.nsIBinaryOutputStream); | |
| 58 stream.setOutputStream(outputStream); | |
| 59 | |
| 60 let manager = new StreamManager(this, stream); | |
| 61 | |
| 62 this.write = function ByteWriter_write(str) { | |
| 63 manager.ensureOpened(); | |
| 64 try { | |
| 65 stream.writeBytes(str, str.length); | |
| 66 } | |
| 67 catch (err) { | |
| 68 throw new Error("Error writing to stream: " + err); | |
| 69 } | |
| 70 }; | |
| 71 } | |
| 72 | |
| 73 | |
| 74 // This manages the lifetime of stream, a ByteReader or ByteWriter. It defines | |
| 75 // closed and close() on stream and registers an unload listener that closes | |
| 76 // rawStream if it's still opened. It also provides ensureOpened(), which | |
| 77 // throws an exception if the stream is closed. | |
| 78 function StreamManager(stream, rawStream) { | |
| 79 const self = this; | |
| 80 this.rawStream = rawStream; | |
| 81 this.opened = true; | |
| 82 | |
| 83 stream.__defineGetter__("closed", function stream_closed() { | |
| 84 return !self.opened; | |
| 85 }); | |
| 86 | |
| 87 stream.close = function stream_close() { | |
| 88 self.ensureOpened(); | |
| 89 self.unload(); | |
| 90 }; | |
| 91 | |
| 92 require("../system/unload").ensure(this); | |
| 93 } | |
| 94 | |
| 95 StreamManager.prototype = { | |
| 96 ensureOpened: function StreamManager_ensureOpened() { | |
| 97 if (!this.opened) | |
| 98 throw new Error("The stream is closed and cannot be used."); | |
| 99 }, | |
| 100 unload: function StreamManager_unload() { | |
| 101 this.rawStream.close(); | |
| 102 this.opened = false; | |
| 103 } | |
| 104 }; |
