xref: /netbsd-src/external/bsd/kyua-cli/dist/utils/process/child.ipp (revision 46b85cbbd3d745f264b248ec8702f62b162c7789)
1// Copyright 2010 Google Inc.
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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::unique_ptr< child >
56child::fork_files(Hook hook, const fs::path& stdout_file,
57                  const fs::path& stderr_file)
58{
59    std::unique_ptr< child > child = fork_files_aux(stdout_file, stderr_file);
60    if (child.get() == NULL) {
61        try {
62            hook();
63            std::abort();
64        } catch (...) {
65            std::abort();
66        }
67    }
68
69    return child;
70}
71
72
73/// Spawns a new subprocess and multiplexes and captures its stdout and stderr.
74///
75/// If the subprocess cannot be completely set up for any reason, it attempts to
76/// dump an error message to its stderr channel and it then calls std::abort().
77///
78/// \param hook The function to execute in the subprocess.  Must not return.
79///
80/// \return A new child object, returned as a dynamically-allocated object
81/// because children classes are unique and thus noncopyable.
82///
83/// \throw process::system_error If the process cannot be spawned due to a
84///     system call error.
85template< typename Hook >
86std::unique_ptr< child >
87child::fork_capture(Hook hook)
88{
89    std::unique_ptr< child > child = fork_capture_aux();
90    if (child.get() == NULL) {
91        try {
92            hook();
93            std::abort();
94        } catch (...) {
95            std::abort();
96        }
97    }
98
99    return child;
100}
101
102
103}  // namespace process
104}  // namespace utils
105
106#endif  // !defined(UTILS_PROCESS_CHILD_IPP)
107