"""
Convenience routines for performing common operations.
@since: 0.28
"""
# Copyright (C) 2009, Thomas Leonard
# See the README file for details, or visit http://0install.net.
import os, sys, logging
from zeroinstall import support
from zeroinstall import _
def get_selections_gui(iface_uri, gui_args, test_callback = None):
"""Run the GUI to choose and download a set of implementations.
The user may ask the GUI to submit a bug report about the program. In that case,
the GUI may ask us to test it. test_callback is called in that case with the implementations
to be tested; the callback will typically call L{zeroinstall.injector.run.test_selections} and return the result of that.
@param iface_uri: the required program, or None to show just the preferences dialog
@type iface_uri: str
@param gui_args: any additional arguments for the GUI itself
@type gui_args: [str]
@param test_callback: function to use to try running the program
@type test_callback: L{zeroinstall.injector.selections.Selections} -> str
@return: the selected implementations
@rtype: L{zeroinstall.injector.selections.Selections}
@since: 0.28
"""
from zeroinstall.injector import selections,qdom
from StringIO import StringIO
from os.path import join,dirname
gui_exe = join(dirname(__file__), '0launch-gui', '0launch-gui')
import socket
cli, gui = socket.socketpair()
try:
child = os.fork()
if child == 0:
# We are the child (GUI)
try:
try:
cli.close()
# We used to use pipes to support Python2.3...
os.dup2(gui.fileno(), 1)
os.dup2(gui.fileno(), 0)
if iface_uri is not None:
gui_args = gui_args + ['--', iface_uri]
os.execvp(gui_exe, [gui_exe] + gui_args)
except:
import traceback
traceback.print_exc(file = sys.stderr)
finally:
sys.stderr.flush()
os._exit(1)
# We are the parent (CLI)
gui.close()
gui = None
while True:
logging.info("Waiting for selections from GUI...")
reply = support.read_bytes(cli.fileno(), len('Length:') + 9, null_ok = True)
if reply:
if not reply.startswith('Length:'):
raise Exception("Expected Length:, but got %s" % repr(reply))
xml = support.read_bytes(cli.fileno(), int(reply.split(':', 1)[1], 16))
dom = qdom.parse(StringIO(xml))
sels = selections.Selections(dom)
if dom.getAttribute('run-test'):
logging.info("Testing program, as requested by GUI...")
if test_callback is None:
output = "Can't test: no test_callback was passed to get_selections_gui()\n"
else:
output = test_callback(sels)
logging.info("Sending results to GUI...")
output = ('Length:%8x\n' % len(output)) + output
logging.debug("Sending: %s", repr(output))
while output:
sent = cli.send(output)
output = output[sent:]
continue
else:
sels = None
pid, status = os.waitpid(child, 0)
assert pid == child
if status == 1 << 8:
logging.info("User cancelled the GUI; aborting")
return None # Aborted
if status != 0:
raise Exception("Error from GUI: code = %d" % status)
break
finally:
for sock in [cli, gui]:
if sock is not None: sock.close()
return sels
def ensure_cached(uri):
"""Ensure that an implementation of uri is cached.
If not, it downloads one. It uses the GUI if a display is
available, or the console otherwise.
@param uri: the required interface
@type uri: str
@return: a new policy for this program, or None if the user cancelled
@rtype: L{zeroinstall.injector.selections.Selections}
"""
from zeroinstall.injector import autopolicy,selections
p = autopolicy.AutoPolicy(uri, download_only = True)
p.freshness = 0 # Don't check for updates
if p.need_download() or not p.ready:
if os.environ.get('DISPLAY', None):
return get_selections_gui(uri, [])
else:
p.recalculate_with_dl()
p.start_downloading_impls()
p.handler.wait_for_downloads()
return selections.Selections(p)
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