process-cpp 3.0.0
A simple convenience library for handling processes in C++11.
exec.cpp
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1/*
2 * Copyright © 2013 Canonical Ltd.
3 *
4 * This program is free software: you can redistribute it and/or modify it
5 * under the terms of the GNU Lesser General Public License version 3,
6 * as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU Lesser General Public License for more details.
12 *
13 * You should have received a copy of the GNU Lesser General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
15 *
16 * Authored by: Thomas Voß <thomas.voss@canonical.com>
17 */
18
19#include <core/posix/exec.h>
20#include <core/posix/fork.h>
22
23#include <iostream>
24
25#include <cstring>
26
27#include <unistd.h>
28
29namespace core
30{
31namespace posix
32{
33ChildProcess exec(const std::string& fn,
34 const std::vector<std::string>& argv,
35 const std::map<std::string, std::string>& env,
36 const StandardStream& flags)
37{
38 std::function<void()> null_function = [](){};
39 return exec(fn, argv, env, flags, null_function);
40}
41
42ChildProcess exec(const std::string& fn,
43 const std::vector<std::string>& argv,
44 const std::map<std::string, std::string>& env,
45 const StandardStream& flags,
46 const std::function<void()>& child_setup)
47{
48 return posix::fork([fn, argv, env, child_setup]()
49 {
50 char** it; char** pargv; char** penv;
51 it = pargv = new char*[argv.size()+2];
52 *it = ::strdup(fn.c_str());
53 it++;
54 for (auto element : argv)
55 {
56 *it = ::strdup(element.c_str());
57 it++;
58 }
59 *it = nullptr;
60
61 it = penv = new char*[env.size()+1];
62 for (auto pair : env)
63 {
64 *it = ::strdup((pair.first + "=" + pair.second).c_str());
65 it++;
66 }
67 *it = nullptr;
68
69 child_setup();
70 return static_cast<posix::exit::Status>(execve(fn.c_str(), pargv, penv));
71 }, flags);
72}
73
74}
75}
The Process class models a child process of this process.
Status
The Status enum wrap's the posix exit status.
Definition exit.h:34
CORE_POSIX_DLL_PUBLIC ChildProcess fork(const std::function< posix::exit::Status()> &main, const StandardStream &flags)
fork forks a new process and executes the provided main function in the newly forked process.
Definition fork.cpp:57
StandardStream
The StandardStream enum wraps the POSIX standard streams.
CORE_POSIX_DLL_PUBLIC ChildProcess exec(const std::string &fn, const std::vector< std::string > &argv, const std::map< std::string, std::string > &env, const StandardStream &flags)
exec execve's the executable with the provided arguments and environment.
Definition exec.cpp:33