diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/core.py | 47 | ||||
| -rwxr-xr-x | src/daemon.py | 21 |
2 files changed, 51 insertions, 17 deletions
diff --git a/src/core.py b/src/core.py index bd83c51f..9609ec44 100644 --- a/src/core.py +++ b/src/core.py @@ -11,6 +11,7 @@ import os import sys import time import curses +import pipes import ssl from functools import reduce @@ -492,17 +493,32 @@ class Core(object): def exec_command(self, command): """ - Execute an external command on the local or a remote - machine, depending on the conf. For example, to open a link in a - browser, do exec_command("firefox http://poezio.eu"), - and this will call the command on the correct computer. - The remote execution is done by writing the command on a fifo. - That fifo has to be on the machine where poezio is running, and - accessible (through sshfs for example) from the local machine (where - poezio is not running). A very simple daemon reads on that fifo, - and executes any command that is read in it. - """ - command = '%s\n' % (command,) + Execute an external command on the local or a remote machine, + depending on the conf. For example, to open a link in a browser, do + exec_command(["firefox", "http://poezio.eu"]), and this will call + the command on the correct computer. + + The command argument is a list of strings, not quoted or escaped in + any way. The escaping is done here if needed. + + The remote execution is done + by writing the command on a fifo. That fifo has to be on the + machine where poezio is running, and accessible (through sshfs for + example) from the local machine (where poezio is not running). A + very simple daemon (daemon.py) reads on that fifo, and executes any + command that is read in it. Since we can only write strings to that + fifo, each argument has to be pipes.quote()d. That way the + shlex.split on the reading-side of the daemon will be safe. + + You cannot use a real command line with pipes, redirections etc, but + this function supports a simple case redirection to file: if the + before-last argument of the command is ">" or ">>", then the last + argument is considered to be a filename where the command stdout + will be written. For example you can do exec_command(["echo", + "coucou les amis coucou coucou", ">", "output.txt"]) and this will + work. If you try to do anything else, your |, [, <<, etc will be + interpreted as normal command arguments, not shell special tokens. + """ if config.get('exec_remote', 'false') == 'true': # We just write the command in the fifo if not self.remote_fifo: @@ -511,16 +527,17 @@ class Core(object): except (OSError, IOError) as e: self.information('Could not open fifo file for writing: %s' % (e,), 'Error') return + command_str = ' '.join([pipes.quote(arg.replace('\n', ' ')) for arg in command]) + '\n' try: - self.remote_fifo.write(command) + self.remote_fifo.write(command_str) except (IOError) as e: - self.information('Could not execute [%s]: %s' % (command.strip(), e,), 'Error') + self.information('Could not execute %s: %s' % (command, e,), 'Error') self.remote_fifo = None else: - e = Executor(command.strip()) + e = Executor(command) try: e.start() - except ValueError as e: # whenever shlex fails + except ValueError as e: self.information('%s' % (e,), 'Error') diff --git a/src/daemon.py b/src/daemon.py index 5d8c9fab..08cf480f 100755 --- a/src/daemon.py +++ b/src/daemon.py @@ -38,17 +38,34 @@ class Executor(threading.Thread): def __init__(self, command): threading.Thread.__init__(self) self.command = command + # check for > or >> special case + self.filename = None + self.redirection_mode = 'w' + if len(command) >= 3: + if command[-2] in ('>', '>>'): + self.filename = command.pop(-1) + if command[-1] == '>>': + self.redirection_mode = 'a' + command.pop(-1) def run(self): log.info('executing %s' % (self.command,)) - subprocess.call(['sh', '-c', self.command]) + stdout = None + if self.filename: + try: + stdout = open(self.filename, self.redirection_mode) + except (OSError, IOError) as e: + log.error('Could not open redirection file: %s (%s)' % (self.filename, e,)) + return + subprocess.call(self.command, stdout=stdout) def main(): while True: line = sys.stdin.readline() if line == '': break - e = Executor(line) + command = shlex.split(line) + e = Executor(command) e.start() if __name__ == '__main__': |