| 1 | # ***** BEGIN LICENSE BLOCK *****
|
|---|
| 2 | # Version: MPL 1.1/GPL 2.0/LGPL 2.1
|
|---|
| 3 | #
|
|---|
| 4 | # The contents of this file are subject to the Mozilla Public License Version
|
|---|
| 5 | # 1.1 (the "License"); you may not use this file except in compliance with
|
|---|
| 6 | # the License. You may obtain a copy of the License at
|
|---|
| 7 | # http://www.mozilla.org/MPL/
|
|---|
| 8 | #
|
|---|
| 9 | # Software distributed under the License is distributed on an "AS IS" basis,
|
|---|
| 10 | # WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
|
|---|
| 11 | # for the specific language governing rights and limitations under the
|
|---|
| 12 | # License.
|
|---|
| 13 | #
|
|---|
| 14 | # The Original Code is the Python XPCOM language bindings.
|
|---|
| 15 | #
|
|---|
| 16 | # The Initial Developer of the Original Code is
|
|---|
| 17 | # ActiveState Tool Corp.
|
|---|
| 18 | # Portions created by the Initial Developer are Copyright (C) 2000, 2001
|
|---|
| 19 | # the Initial Developer. All Rights Reserved.
|
|---|
| 20 | #
|
|---|
| 21 | # Contributor(s):
|
|---|
| 22 | # Mark Hammond <[email protected]> (original author)
|
|---|
| 23 | #
|
|---|
| 24 | # Alternatively, the contents of this file may be used under the terms of
|
|---|
| 25 | # either the GNU General Public License Version 2 or later (the "GPL"), or
|
|---|
| 26 | # the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
|
|---|
| 27 | # in which case the provisions of the GPL or the LGPL are applicable instead
|
|---|
| 28 | # of those above. If you wish to allow use of your version of this file only
|
|---|
| 29 | # under the terms of either the GPL or the LGPL, and not to allow others to
|
|---|
| 30 | # use your version of this file under the terms of the MPL, indicate your
|
|---|
| 31 | # decision by deleting the provisions above and replace them with the notice
|
|---|
| 32 | # and other provisions required by the GPL or the LGPL. If you do not delete
|
|---|
| 33 | # the provisions above, a recipient may use your version of this file under
|
|---|
| 34 | # the terms of any one of the MPL, the GPL or the LGPL.
|
|---|
| 35 | #
|
|---|
| 36 | # ***** END LICENSE BLOCK *****
|
|---|
| 37 |
|
|---|
| 38 | """Implementation of Python file objects for Mozilla/xpcom.
|
|---|
| 39 |
|
|---|
| 40 | Introduction:
|
|---|
| 41 | This module defines various class that are implemented using
|
|---|
| 42 | Mozilla streams. This allows you to open Mozilla URI's, and
|
|---|
| 43 | treat them as Python file object.
|
|---|
| 44 |
|
|---|
| 45 | Example:
|
|---|
| 46 | >>> file = URIFile("chrome://whatever")
|
|---|
| 47 | >>> data = file.read(5) # Pass no arg to read everything.
|
|---|
| 48 |
|
|---|
| 49 | Known Limitations:
|
|---|
| 50 | * Not all URL schemes will work from "python.exe" - most notably
|
|---|
| 51 | "chrome://" and "http://" URLs - this is because a simple initialization of
|
|---|
| 52 | xpcom by Python does not load up the full set of Mozilla URL handlers.
|
|---|
| 53 | If you can work out how to correctly initialize the chrome registry and
|
|---|
| 54 | setup a message queue.
|
|---|
| 55 |
|
|---|
| 56 | Known Bugs:
|
|---|
| 57 | * Only read ("r") mode is supported. Although write ("w") mode doesnt make
|
|---|
| 58 | sense for HTTP type URLs, it potentially does for file:// etc type ones.
|
|---|
| 59 | * No concept of text mode vs binary mode. It appears Mozilla takes care of
|
|---|
| 60 | this internally (ie, all "text/???" mime types are text, rest are binary)
|
|---|
| 61 |
|
|---|
| 62 | """
|
|---|
| 63 |
|
|---|
| 64 | from xpcom import components, Exception, _xpcom
|
|---|
| 65 | import os
|
|---|
| 66 | import threading # for locks.
|
|---|
| 67 |
|
|---|
| 68 | NS_RDONLY = 0x01
|
|---|
| 69 | NS_WRONLY = 0x02
|
|---|
| 70 | NS_RDWR = 0x04
|
|---|
| 71 | NS_CREATE_FILE = 0x08
|
|---|
| 72 | NS_APPEND = 0x10
|
|---|
| 73 | NS_TRUNCATE = 0x20
|
|---|
| 74 | NS_SYNC = 0x40
|
|---|
| 75 | NS_EXCL = 0x80
|
|---|
| 76 |
|
|---|
| 77 | # A helper function that may come in useful
|
|---|
| 78 | def LocalFileToURL(localFileName):
|
|---|
| 79 | "Convert a filename to an XPCOM nsIFileURL object."
|
|---|
| 80 | # Create an nsILocalFile
|
|---|
| 81 | localFile = components.classes["@mozilla.org/file/local;1"] \
|
|---|
| 82 | .createInstance(components.interfaces.nsILocalFile)
|
|---|
| 83 | localFile.initWithPath(localFileName)
|
|---|
| 84 |
|
|---|
| 85 | # Use the IO Service to create the interface, then QI for a FileURL
|
|---|
| 86 | io_service = components.classes["@mozilla.org/network/io-service;1"] \
|
|---|
| 87 | .getService(components.interfaces.nsIIOService)
|
|---|
| 88 | url = io_service.newFileURI(localFile).queryInterface(components.interfaces.nsIFileURL)
|
|---|
| 89 | # Setting the "file" attribute causes initialization...
|
|---|
| 90 | url.file = localFile
|
|---|
| 91 | return url
|
|---|
| 92 |
|
|---|
| 93 | # A base class for file objects.
|
|---|
| 94 | class _File:
|
|---|
| 95 | def __init__(self, name_thingy = None, mode="r"):
|
|---|
| 96 | self.lockob = threading.Lock()
|
|---|
| 97 | self.inputStream = self.outputStream = None
|
|---|
| 98 | if name_thingy is not None:
|
|---|
| 99 | self.init(name_thingy, mode)
|
|---|
| 100 |
|
|---|
| 101 | def __del__(self):
|
|---|
| 102 | self.close()
|
|---|
| 103 |
|
|---|
| 104 | # The Moz file streams are not thread safe.
|
|---|
| 105 | def _lock(self):
|
|---|
| 106 | self.lockob.acquire()
|
|---|
| 107 | def _release(self):
|
|---|
| 108 | self.lockob.release()
|
|---|
| 109 | def read(self, n = -1):
|
|---|
| 110 | assert self.inputStream is not None, "Not setup for read!"
|
|---|
| 111 | self._lock()
|
|---|
| 112 | try:
|
|---|
| 113 | return str(self.inputStream.read(n))
|
|---|
| 114 | finally:
|
|---|
| 115 | self._release()
|
|---|
| 116 |
|
|---|
| 117 | def readlines(self):
|
|---|
| 118 | # Not part of the xpcom interface, but handy for direct Python users.
|
|---|
| 119 | # Not 100% faithful, but near enough for now!
|
|---|
| 120 | lines = self.read().split("\n")
|
|---|
| 121 | if len(lines) and len(lines[-1]) == 0:
|
|---|
| 122 | lines = lines[:-1]
|
|---|
| 123 | return [s+"\n" for s in lines ]
|
|---|
| 124 |
|
|---|
| 125 | def write(self, data):
|
|---|
| 126 | assert self.outputStream is not None, "Not setup for write!"
|
|---|
| 127 | self._lock()
|
|---|
| 128 | try:
|
|---|
| 129 | self.outputStream.write(data, len(data))
|
|---|
| 130 | finally:
|
|---|
| 131 | self._release()
|
|---|
| 132 |
|
|---|
| 133 | def close(self):
|
|---|
| 134 | self._lock()
|
|---|
| 135 | try:
|
|---|
| 136 | if self.inputStream is not None:
|
|---|
| 137 | self.inputStream.close()
|
|---|
| 138 | self.inputStream = None
|
|---|
| 139 | if self.outputStream is not None:
|
|---|
| 140 | self.outputStream.close()
|
|---|
| 141 | self.outputStream = None
|
|---|
| 142 | self.channel = None
|
|---|
| 143 | finally:
|
|---|
| 144 | self._release()
|
|---|
| 145 |
|
|---|
| 146 | def flush(self):
|
|---|
| 147 | self._lock()
|
|---|
| 148 | try:
|
|---|
| 149 | if self.outputStream is not None: self.outputStream.flush()
|
|---|
| 150 | finally:
|
|---|
| 151 | self._release()
|
|---|
| 152 |
|
|---|
| 153 | # A synchronous "file object" used to open a URI.
|
|---|
| 154 | class URIFile(_File):
|
|---|
| 155 | def init(self, url, mode="r"):
|
|---|
| 156 | self.close()
|
|---|
| 157 | if mode != "r":
|
|---|
| 158 | raise ValueError("only 'r' mode supported")
|
|---|
| 159 | io_service = components.classes["@mozilla.org/network/io-service;1"] \
|
|---|
| 160 | .getService(components.interfaces.nsIIOService)
|
|---|
| 161 | if hasattr(url, "queryInterface"):
|
|---|
| 162 | url_ob = url
|
|---|
| 163 | else:
|
|---|
| 164 | url_ob = io_service.newURI(url, None, None)
|
|---|
| 165 | # Mozilla asserts and starts saying "NULL POINTER" if this is wrong!
|
|---|
| 166 | if not url_ob.scheme:
|
|---|
| 167 | raise ValueError("The URI '%s' is invalid (no scheme)"
|
|---|
| 168 | % (url_ob.spec,))
|
|---|
| 169 | self.channel = io_service.newChannelFromURI(url_ob)
|
|---|
| 170 | self.inputStream = self.channel.open()
|
|---|
| 171 |
|
|---|
| 172 | # A "file object" implemented using Netscape's native file support.
|
|---|
| 173 | # Based on io.js - http://lxr.mozilla.org/seamonkey/source/xpcom/tests/utils/io.js
|
|---|
| 174 | # You open this file using a local file name (as a string) so it really is pointless -
|
|---|
| 175 | # you may as well be using a standard Python file object!
|
|---|
| 176 | class LocalFile(_File):
|
|---|
| 177 | def __init__(self, *args):
|
|---|
| 178 | self.fileIO = None
|
|---|
| 179 | _File.__init__(self, *args)
|
|---|
| 180 |
|
|---|
| 181 | def init(self, name, mode = "r"):
|
|---|
| 182 | name = os.path.abspath(name) # Moz libraries under Linux fail with relative paths.
|
|---|
| 183 | self.close()
|
|---|
| 184 | file = components.classes['@mozilla.org/file/local;1'].createInstance("nsILocalFile")
|
|---|
| 185 | file.initWithPath(name)
|
|---|
| 186 | if mode in ["w","a"]:
|
|---|
| 187 | self.fileIO = components.classes["@mozilla.org/network/file-output-stream;1"].createInstance("nsIFileOutputStream")
|
|---|
| 188 | if mode== "w":
|
|---|
| 189 | if file.exists():
|
|---|
| 190 | file.remove(0)
|
|---|
| 191 | moz_mode = NS_CREATE_FILE | NS_WRONLY
|
|---|
| 192 | elif mode=="a":
|
|---|
| 193 | moz_mode = NS_APPEND
|
|---|
| 194 | else:
|
|---|
| 195 | assert 0, "Can't happen!"
|
|---|
| 196 | self.fileIO.init(file, moz_mode, -1,0)
|
|---|
| 197 | self.outputStream = self.fileIO
|
|---|
| 198 | elif mode == "r":
|
|---|
| 199 | self.fileIO = components.classes["@mozilla.org/network/file-input-stream;1"].createInstance("nsIFileInputStream")
|
|---|
| 200 | self.fileIO.init(file, NS_RDONLY, -1,0)
|
|---|
| 201 | self.inputStream = components.classes["@mozilla.org/scriptableinputstream;1"].createInstance("nsIScriptableInputStream")
|
|---|
| 202 | self.inputStream.init(self.fileIO)
|
|---|
| 203 | else:
|
|---|
| 204 | raise ValueError("Unknown mode")
|
|---|
| 205 |
|
|---|
| 206 | def close(self):
|
|---|
| 207 | if self.fileIO is not None:
|
|---|
| 208 | self.fileIO.close()
|
|---|
| 209 | self.fileIO = None
|
|---|
| 210 | _File.close(self)
|
|---|
| 211 |
|
|---|
| 212 | def read(self, n = -1):
|
|---|
| 213 | return _File.read(self, n)
|
|---|
| 214 |
|
|---|
| 215 |
|
|---|
| 216 | ##########################################################
|
|---|
| 217 | ##
|
|---|
| 218 | ## Test Code
|
|---|
| 219 | ##
|
|---|
| 220 | ##########################################################
|
|---|
| 221 | def _DoTestRead(file, expected):
|
|---|
| 222 | # read in a couple of chunks, just to test that our various arg combinations work.
|
|---|
| 223 | got = file.read(3)
|
|---|
| 224 | got = got + file.read(300)
|
|---|
| 225 | got = got + file.read(0)
|
|---|
| 226 | got = got + file.read()
|
|---|
| 227 | if got != expected:
|
|---|
| 228 | raise RuntimeError("Reading '%s' failed - got %d bytes, but expected %d bytes" % (file, len(got), len(expected)))
|
|---|
| 229 |
|
|---|
| 230 | def _DoTestBufferRead(file, expected):
|
|---|
| 231 | # read in a couple of chunks, just to test that our various arg combinations work.
|
|---|
| 232 | buffer = _xpcom.AllocateBuffer(50)
|
|---|
| 233 | got = ''
|
|---|
| 234 | while 1:
|
|---|
| 235 | # Note - we need to reach into the file object so we
|
|---|
| 236 | # can get at the native buffer supported function.
|
|---|
| 237 | num = file.inputStream.read(buffer)
|
|---|
| 238 | if num == 0:
|
|---|
| 239 | break
|
|---|
| 240 | got = got + str(buffer[:num])
|
|---|
| 241 | if got != expected:
|
|---|
| 242 | raise RuntimeError("Reading '%s' failed - got %d bytes, but expected %d bytes" % (file, len(got), len(expected)))
|
|---|
| 243 |
|
|---|
| 244 | def _TestLocalFile():
|
|---|
| 245 | import tempfile, os
|
|---|
| 246 | fname = tempfile.mktemp()
|
|---|
| 247 | data = "Hello from Python"
|
|---|
| 248 | test_file = LocalFile(fname, "w")
|
|---|
| 249 | try:
|
|---|
| 250 | test_file.write(data)
|
|---|
| 251 | test_file.close()
|
|---|
| 252 | # Make sure Python can read it OK.
|
|---|
| 253 | f = open(fname, "r")
|
|---|
| 254 | assert f.read() == data, "Eeek - Python could not read the data back correctly!"
|
|---|
| 255 | f.close()
|
|---|
| 256 | # For the sake of the test, try a re-init.
|
|---|
| 257 | test_file.init(fname, "r")
|
|---|
| 258 | got = str(test_file.read())
|
|---|
| 259 | assert got == data, got
|
|---|
| 260 | test_file.close()
|
|---|
| 261 | # Try reading in chunks.
|
|---|
| 262 | test_file = LocalFile(fname, "r")
|
|---|
| 263 | got = test_file.read(10) + test_file.read()
|
|---|
| 264 | assert got == data, got
|
|---|
| 265 | test_file.close()
|
|---|
| 266 | # Open the same file again for writing - this should delete the old one.
|
|---|
| 267 | if not os.path.isfile(fname):
|
|---|
| 268 | raise RuntimeError("The file '%s' does not exist, but we are explicitly testing create semantics when it does" % (fname,))
|
|---|
| 269 | test_file = LocalFile(fname, "w")
|
|---|
| 270 | test_file.write(data)
|
|---|
| 271 | test_file.close()
|
|---|
| 272 | # Make sure Python can read it OK.
|
|---|
| 273 | f = open(fname, "r")
|
|---|
| 274 | assert f.read() == data, "Eeek - Python could not read the data back correctly after recreating an existing file!"
|
|---|
| 275 | f.close()
|
|---|
| 276 |
|
|---|
| 277 | # XXX - todo - test "a" mode!
|
|---|
| 278 | finally:
|
|---|
| 279 | os.unlink(fname)
|
|---|
| 280 |
|
|---|
| 281 | def _TestAll():
|
|---|
| 282 | # A mini test suite.
|
|---|
| 283 | # Get a test file, and convert it to a file:// URI.
|
|---|
| 284 | # check what we read is the same as when
|
|---|
| 285 | # we read this file "normally"
|
|---|
| 286 | fname = components.__file__
|
|---|
| 287 | if fname[-1] in "cCoO": # fix .pyc/.pyo
|
|---|
| 288 | fname = fname[:-1]
|
|---|
| 289 | expected = open(fname, "rb").read()
|
|---|
| 290 | # convert the fname to a URI.
|
|---|
| 291 | url = LocalFileToURL(fname)
|
|---|
| 292 | # First try passing a URL as a string.
|
|---|
| 293 | _DoTestRead( URIFile( url.spec), expected)
|
|---|
| 294 | # Now with a URL object.
|
|---|
| 295 | _DoTestRead( URIFile( url ), expected)
|
|---|
| 296 |
|
|---|
| 297 | _DoTestBufferRead( URIFile( url ), expected)
|
|---|
| 298 |
|
|---|
| 299 | # For the sake of testing, do our pointless, demo object!
|
|---|
| 300 | _DoTestRead( LocalFile(fname), expected )
|
|---|
| 301 |
|
|---|
| 302 | # Now do the full test of our pointless, demo object!
|
|---|
| 303 | _TestLocalFile()
|
|---|
| 304 |
|
|---|
| 305 | def _TestURI(url):
|
|---|
| 306 | test_file = URIFile(url)
|
|---|
| 307 | print("Opened file is", test_file)
|
|---|
| 308 | got = test_file.read()
|
|---|
| 309 | print("Read %d bytes of data from %r" % (len(got), url))
|
|---|
| 310 | test_file.close()
|
|---|
| 311 |
|
|---|
| 312 | if __name__=='__main__':
|
|---|
| 313 | import sys
|
|---|
| 314 | if len(sys.argv) < 2:
|
|---|
| 315 | print("No URL specified on command line - performing self-test")
|
|---|
| 316 | _TestAll()
|
|---|
| 317 | else:
|
|---|
| 318 | _TestURI(sys.argv[1])
|
|---|
