xref: /freebsd/contrib/kyua/utils/process/child.ipp (revision 1f474190)
1// Copyright 2010 The Kyua Authors.
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met:
7//
8// * Redistributions of source code must retain the above copyright
9//   notice, this list of conditions and the following disclaimer.
10// * Redistributions in binary form must reproduce the above copyright
11//   notice, this list of conditions and the following disclaimer in the
12//   documentation and/or other materials provided with the distribution.
13// * Neither the name of Google Inc. nor the names of its contributors
14//   may be used to endorse or promote products derived from this software
15//   without specific prior written permission.
16//
17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
29#if !defined(UTILS_PROCESS_CHILD_IPP)
30#define UTILS_PROCESS_CHILD_IPP
31
32#include <cstdlib>
33
34#include "utils/process/child.hpp"
35
36namespace utils {
37namespace process {
38
39
40/// Spawns a new subprocess and redirects its stdout and stderr to files.
41///
42/// If the subprocess cannot be completely set up for any reason, it attempts to
43/// dump an error message to its stderr channel and it then calls std::abort().
44///
45/// \param hook The function to execute in the subprocess.  Must not return.
46/// \param stdout_file The name of the file in which to store the stdout.
47/// \param stderr_file The name of the file in which to store the stderr.
48///
49/// \return A new child object, returned as a dynamically-allocated object
50/// because children classes are unique and thus noncopyable.
51///
52/// \throw process::system_error If the process cannot be spawned due to a
53///     system call error.
54template< typename Hook >
55std::auto_ptr< child >
56child::fork_files(Hook hook, const fs::path& stdout_file,
57                  const fs::path& stderr_file)
58{
59    std::auto_ptr< child > child = fork_files_aux(stdout_file, stderr_file);
60    if (child.get() == NULL) {
61        try {
62            hook();
63            std::abort();
64        } catch (const std::runtime_error& e) {
65            detail::report_error_and_abort(e);
66        } catch (...) {
67            detail::report_error_and_abort();
68        }
69    }
70
71    return child;
72}
73
74
75/// Spawns a new subprocess and multiplexes and captures its stdout and stderr.
76///
77/// If the subprocess cannot be completely set up for any reason, it attempts to
78/// dump an error message to its stderr channel and it then calls std::abort().
79///
80/// \param hook The function to execute in the subprocess.  Must not return.
81///
82/// \return A new child object, returned as a dynamically-allocated object
83/// because children classes are unique and thus noncopyable.
84///
85/// \throw process::system_error If the process cannot be spawned due to a
86///     system call error.
87template< typename Hook >
88std::auto_ptr< child >
89child::fork_capture(Hook hook)
90{
91    std::auto_ptr< child > child = fork_capture_aux();
92    if (child.get() == NULL) {
93        try {
94            hook();
95            std::abort();
96        } catch (const std::runtime_error& e) {
97            detail::report_error_and_abort(e);
98        } catch (...) {
99            detail::report_error_and_abort();
100        }
101    }
102
103    return child;
104}
105
106
107}  // namespace process
108}  // namespace utils
109
110#endif  // !defined(UTILS_PROCESS_CHILD_IPP)
111