00001 """\
00002 @file llsubprocess.py
00003 @author Phoenix
00004 @date 2008-01-18
00005 @brief The simplest possible wrapper for a common sub-process paradigm.
00006
00007 $LicenseInfo:firstyear=2007&license=mit$
00008
00009 Copyright (c) 2007-2008, Linden Research, Inc.
00010
00011 Permission is hereby granted, free of charge, to any person obtaining a copy
00012 of this software and associated documentation files (the "Software"), to deal
00013 in the Software without restriction, including without limitation the rights
00014 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00015 copies of the Software, and to permit persons to whom the Software is
00016 furnished to do so, subject to the following conditions:
00017
00018 The above copyright notice and this permission notice shall be included in
00019 all copies or substantial portions of the Software.
00020
00021 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00022 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00023 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00024 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00025 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00026 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00027 THE SOFTWARE.
00028 $/LicenseInfo$
00029 """
00030
00031 import os
00032 import popen2
00033 import time
00034 import select
00035
00036 class Timeout(RuntimeError):
00037 "Exception raised when a subprocess times out."
00038 pass
00039
00040 def run(command, args=None, data=None, timeout=None):
00041 """\
00042 @brief Run command with arguments
00043
00044 This is it. This is the function I want to run all the time when doing
00045 subprocces, but end up copying the code everywhere. none of the
00046 standard commands are secure and provide a way to specify input, get
00047 all the output, and get the result.
00048 @param command A string specifying a process to launch.
00049 @param args Arguments to be passed to command. Must be list, tuple or None.
00050 @param data input to feed to the command.
00051 @param timeout Maximum number of many seconds to run.
00052 @return Returns (result, stdout, stderr) from process.
00053 """
00054 cmd = [command]
00055 if args:
00056 cmd.extend([str(arg) for arg in args])
00057
00058 child = popen2.Popen3(cmd, True)
00059
00060 out = []
00061 err = []
00062 result = -1
00063 time_left = timeout
00064 tochild = [child.tochild.fileno()]
00065 while True:
00066 time_start = time.time()
00067
00068 p_in, p_out, p_err = select.select(
00069 [child.fromchild.fileno(), child.childerr.fileno()],
00070 tochild,
00071 [],
00072 time_left)
00073 if p_in:
00074 new_line = os.read(child.fromchild.fileno(), 32 * 1024)
00075 if new_line:
00076
00077 out.append(new_line)
00078 new_line = os.read(child.childerr.fileno(), 32 * 1024)
00079 if new_line:
00080
00081 err.append(new_line)
00082 if p_out:
00083 if data:
00084
00085 bytes = os.write(child.tochild.fileno(), data)
00086 data = data[bytes:]
00087 if len(data) == 0:
00088 data = None
00089 tochild = []
00090 child.tochild.close()
00091 result = child.poll()
00092 if result != -1:
00093 child.tochild.close()
00094 child.fromchild.close()
00095 child.childerr.close()
00096 break
00097 if time_left is not None:
00098 time_left -= (time.time() - time_start)
00099 if time_left < 0:
00100 raise Timeout
00101
00102 out = ''.join(out)
00103
00104 err = ''.join(err)
00105
00106 return result, out, err