1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/*****************************************************************************
*
* X testing environment - Google Test environment featuring dummy x server
*
* Copyright (C) 2011 Canonical Ltd.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http://www.gnu.org/licenses/>.
*
****************************************************************************/
#ifndef XORG_GTEST_PROCESS_H
#define XORG_GTEST_PROCESS_H
#include <stdarg.h>
#include <memory>
#include <string>
namespace xorg {
namespace testing {
/**
* @class Process test.h xorg/gtest/process.h
*
* Class that abstracts child process creation and termination.
*
* This class allows for forking, running and terminating child processes.
* In addition, manipulation of the child process' environment is supported.
* For example, starting an X server instance on display port 133 as a child
* process can be realized with the following code snippet:
* @code
* Process xorgServer;
* try {
* xorgServer.Start("Xorg", "Xorg", ":133");
* } catch (const std::runtime_error&e) {
* std::cerr << "Problem starting the X server: " << e.what() << std::endl;
* }
* ...
* if (!xorgServer.Terminate()) {
* std::cerr << "Problem terminating server ... killing now ..." << std::endl;
* if (!xorgServer.Kill())
* std::cerr << "Problem killing server" << std::endl;
* }
* @endcode
*/
class Process {
public:
/**
* Helper function to adjust the environment of the current process.
*
* @param [in] name Name of the environment variable.
* @param [in] value Value of the environment variable.
* @param [in] overwrite Whether to overwrite the value of existing env
* variables.
*
* @throws std::runtime_error if adjusting the environment does not succeed.
*/
static void SetEnv(const std::string& name, const std::string& value,
bool overwrite);
/**
* Helper function to query the environment of the current process.
*
* @param [in] name The name of the environment variable.
* @param [out] exists If not NULL, the variable will be set to true if the
* environment variable exists and to false otherwise.
* @returns The value of the environment variable, or an empty string.
*/
static std::string GetEnv(const std::string& name, bool* exists = NULL);
/**
* Creates a child-process that is in a terminated state.
*/
Process();
/**
* Starts a program as a child process.
*
* See 'man execvp' for further information on the variadic argument list.
*
* @param program The program to start.
* @param args Variadic list of arguments passed to the program.
*
* @throws std::runtime_error on failure.
*
* @post If successful: Child process forked and program started.
* @post If successful: Subsequent calls to Pid() return child process pid.
*/
void Start(const std::string& program, va_list args);
/**
* Starts a program as a child process.
*
* Takes a variadic list of arguments passed to the program.
* See 'man execvp' for further information on the variadic argument list.
*
* @param program The program to start.
*
* @throws std::runtime_error on failure.
*
* @post If successful: Child process forked and program started.
* @post If successful: Subsequent calls to Pid() return child process pid.
*/
void Start(const std::string& program, ...);
/**
* Terminates (SIGTERM) this child process.
*
* @throws std::runtime_error if child tries to terminate itself.
*
* @returns true if termination succeeded, false otherwise.
*
* @post If successful: Child process terminated.
* @post If successful: Subsequent calls to Pid() return -1.
*/
bool Terminate();
/**
* Kills (SIGKILL) this child process.
*
* @throws std::runtime_error if child tries to kill itself.
*
* @returns true if kill succeeded, false otherwise.
*
* @post If successful: Child process killed.
* @post If successful: Subsequent calls to Pid() return -1.
*/
bool Kill();
/**
* Accesses the pid of the child process.
*
* @returns The pid of the child process or -1.
*/
pid_t Pid() const;
private:
struct Private;
std::auto_ptr<Private> d_;
/* Disable copy constructor, assignment operator */
Process(const Process&);
Process& operator=(const Process&);
};
} // testing
} // xorg
#endif // XORG_GTEST_PROCESS_H
|
