diff options
Diffstat (limited to 'addon-sdk/source/lib/sdk/io/text-streams.js')
| -rw-r--r-- | addon-sdk/source/lib/sdk/io/text-streams.js | 235 |
1 files changed, 0 insertions, 235 deletions
diff --git a/addon-sdk/source/lib/sdk/io/text-streams.js b/addon-sdk/source/lib/sdk/io/text-streams.js deleted file mode 100644 index ed4ec4972..000000000 --- a/addon-sdk/source/lib/sdk/io/text-streams.js +++ /dev/null @@ -1,235 +0,0 @@ -/* This Source Code Form is subject to the terms of the Mozilla Public - * License, v. 2.0. If a copy of the MPL was not distributed with this - * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ -"use strict"; - -module.metadata = { - "stability": "experimental" -}; - -const { Cc, Ci, Cu, components } = require("chrome"); -const { ensure } = require("../system/unload"); -const { NetUtil } = Cu.import("resource://gre/modules/NetUtil.jsm", {}); - -// NetUtil.asyncCopy() uses this buffer length, and since we call it, for best -// performance we use it, too. -const BUFFER_BYTE_LEN = 0x8000; -const PR_UINT32_MAX = 0xffffffff; -const DEFAULT_CHARSET = "UTF-8"; - - -/** - * An input stream that reads text from a backing stream using a given text - * encoding. - * - * @param inputStream - * The stream is backed by this nsIInputStream. It must already be - * opened. - * @param charset - * Text in inputStream is expected to be in this character encoding. If - * not given, "UTF-8" is assumed. See nsICharsetConverterManager.idl for - * documentation on how to determine other valid values for this. - */ -function TextReader(inputStream, charset) { - charset = checkCharset(charset); - - let stream = Cc["@mozilla.org/intl/converter-input-stream;1"]. - createInstance(Ci.nsIConverterInputStream); - stream.init(inputStream, charset, BUFFER_BYTE_LEN, - Ci.nsIConverterInputStream.DEFAULT_REPLACEMENT_CHARACTER); - - let manager = new StreamManager(this, stream); - - /** - * Reads a string from the stream. If the stream is closed, an exception is - * thrown. - * - * @param numChars - * The number of characters to read. If not given, the remainder of - * the stream is read. - * @return The string read. If the stream is already at EOS, returns the - * empty string. - */ - this.read = function TextReader_read(numChars) { - manager.ensureOpened(); - - let readAll = false; - if (typeof(numChars) === "number") - numChars = Math.max(numChars, 0); - else - readAll = true; - - let str = ""; - let totalRead = 0; - let chunkRead = 1; - - // Read in numChars or until EOS, whichever comes first. Note that the - // units here are characters, not bytes. - while (true) { - let chunk = {}; - let toRead = readAll ? - PR_UINT32_MAX : - Math.min(numChars - totalRead, PR_UINT32_MAX); - if (toRead <= 0 || chunkRead <= 0) - break; - - // The converter stream reads in at most BUFFER_BYTE_LEN bytes in a call - // to readString, enough to fill its byte buffer. chunkRead will be the - // number of characters encoded by the bytes in that buffer. - chunkRead = stream.readString(toRead, chunk); - str += chunk.value; - totalRead += chunkRead; - } - - return str; - }; -} -exports.TextReader = TextReader; - -/** - * A buffered output stream that writes text to a backing stream using a given - * text encoding. - * - * @param outputStream - * The stream is backed by this nsIOutputStream. It must already be - * opened. - * @param charset - * Text will be written to outputStream using this character encoding. - * If not given, "UTF-8" is assumed. See nsICharsetConverterManager.idl - * for documentation on how to determine other valid values for this. - */ -function TextWriter(outputStream, charset) { - charset = checkCharset(charset); - - let stream = outputStream; - - // Buffer outputStream if it's not already. - let ioUtils = Cc["@mozilla.org/io-util;1"].getService(Ci.nsIIOUtil); - if (!ioUtils.outputStreamIsBuffered(outputStream)) { - stream = Cc["@mozilla.org/network/buffered-output-stream;1"]. - createInstance(Ci.nsIBufferedOutputStream); - stream.init(outputStream, BUFFER_BYTE_LEN); - } - - // I'd like to use nsIConverterOutputStream. But NetUtil.asyncCopy(), which - // we use below in writeAsync(), naturally expects its sink to be an instance - // of nsIOutputStream, which nsIConverterOutputStream's only implementation is - // not. So we use uconv and manually convert all strings before writing to - // outputStream. - let uconv = Cc["@mozilla.org/intl/scriptableunicodeconverter"]. - createInstance(Ci.nsIScriptableUnicodeConverter); - uconv.charset = charset; - - let manager = new StreamManager(this, stream); - - /** - * Flushes the backing stream's buffer. - */ - this.flush = function TextWriter_flush() { - manager.ensureOpened(); - stream.flush(); - }; - - /** - * Writes a string to the stream. If the stream is closed, an exception is - * thrown. - * - * @param str - * The string to write. - */ - this.write = function TextWriter_write(str) { - manager.ensureOpened(); - let istream = uconv.convertToInputStream(str); - let len = istream.available(); - while (len > 0) { - stream.writeFrom(istream, len); - len = istream.available(); - } - istream.close(); - }; - - /** - * Writes a string on a background thread. After the write completes, the - * backing stream's buffer is flushed, and both the stream and the backing - * stream are closed, also on the background thread. If the stream is already - * closed, an exception is thrown immediately. - * - * @param str - * The string to write. - * @param callback - * An optional function. If given, it's called as callback(error) when - * the write completes. error is an Error object or undefined if there - * was no error. Inside callback, |this| is the stream object. - */ - this.writeAsync = function TextWriter_writeAsync(str, callback) { - manager.ensureOpened(); - let istream = uconv.convertToInputStream(str); - NetUtil.asyncCopy(istream, stream, (result) => { - let err = components.isSuccessCode(result) ? undefined : - new Error("An error occured while writing to the stream: " + result); - if (err) - console.error(err); - - // asyncCopy() closes its output (and input) stream. - manager.opened = false; - - if (typeof(callback) === "function") { - try { - callback.call(this, err); - } - catch (exc) { - console.exception(exc); - } - } - }); - }; -} -exports.TextWriter = TextWriter; - -// This manages the lifetime of stream, a TextReader or TextWriter. It defines -// closed and close() on stream and registers an unload listener that closes -// rawStream if it's still opened. It also provides ensureOpened(), which -// throws an exception if the stream is closed. -function StreamManager(stream, rawStream) { - this.rawStream = rawStream; - this.opened = true; - - /** - * True iff the stream is closed. - */ - stream.__defineGetter__("closed", () => !this.opened); - - /** - * Closes both the stream and its backing stream. If the stream is already - * closed, an exception is thrown. For TextWriters, this first flushes the - * backing stream's buffer. - */ - stream.close = () => { - this.ensureOpened(); - this.unload(); - }; - - ensure(this); -} - -StreamManager.prototype = { - ensureOpened: function StreamManager_ensureOpened() { - if (!this.opened) - throw new Error("The stream is closed and cannot be used."); - }, - unload: function StreamManager_unload() { - // TextWriter.writeAsync() causes rawStream to close and therefore sets - // opened to false, so check that we're still opened. - if (this.opened) { - // Calling close() on both an nsIUnicharInputStream and - // nsIBufferedOutputStream closes their backing streams. It also forces - // nsIOutputStreams to flush first. - this.rawStream.close(); - this.opened = false; - } - } -}; - -function checkCharset(charset) { - return typeof(charset) === "string" ? charset : DEFAULT_CHARSET; -} |