1 /* Test of create_pipe_bidi/wait_subprocess.
2 Copyright (C) 2009-2020 Free Software Foundation, Inc.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3, or (at your option)
7 any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, see <https://www.gnu.org/licenses/>. */
16
17 #include <config.h>
18
19 #include "spawn-pipe.h"
20 #include "wait-process.h"
21
22 #include <stdbool.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <unistd.h>
27
28 /* Depending on arguments, this test intentionally closes stderr or
29 starts life with stderr closed. So, we arrange to have fd 10
30 (outside the range of interesting fd's during the test) set up to
31 duplicate the original stderr. */
32
33 #define BACKUP_STDERR_FILENO 10
34 #define ASSERT_STREAM myerr
35 #include "macros.h"
36
37 static FILE *myerr;
38
39 /* Create a bi-directional pipe to a test child, and validate that the
40 child program returns the expected output.
41 PROG is the program to run in the child process.
42 STDERR_CLOSED is true if we have already closed fd 2. */
43 static void
test_pipe(const char * prog,bool stderr_closed)44 test_pipe (const char *prog, bool stderr_closed)
45 {
46 int fd[2];
47 char *argv[3];
48 pid_t pid;
49 char buffer[2] = { 'a', 't' };
50
51 /* Set up child. */
52 argv[0] = (char *) prog;
53 argv[1] = (char *) (stderr_closed ? "1" : "0");
54 argv[2] = NULL;
55 pid = create_pipe_bidi (prog, prog, argv, false, true, true, fd);
56 ASSERT (0 <= pid);
57 ASSERT (STDERR_FILENO < fd[0]);
58 ASSERT (STDERR_FILENO < fd[1]);
59
60 /* Push child's input. */
61 ASSERT (write (fd[1], buffer, 1) == 1);
62 ASSERT (close (fd[1]) == 0);
63
64 /* Get child's output. */
65 ASSERT (read (fd[0], buffer, 2) == 1);
66
67 /* Wait for child. */
68 ASSERT (wait_subprocess (pid, prog, true, false, true, true, NULL) == 0);
69 ASSERT (close (fd[0]) == 0);
70
71 /* Check the result. */
72 ASSERT (buffer[0] == 'b');
73 ASSERT (buffer[1] == 't');
74 }
75
76 int
main(int argc,char * argv[])77 main (int argc, char *argv[])
78 {
79 int test;
80 int fd;
81
82 if (argc != 3)
83 {
84 fprintf (stderr, "%s: need 2 arguments\n", argv[0]);
85 return 2;
86 }
87 /* We might close fd 2 later, so save it in fd 10. */
88 if (dup2 (STDERR_FILENO, BACKUP_STDERR_FILENO) != BACKUP_STDERR_FILENO
89 || (myerr = fdopen (BACKUP_STDERR_FILENO, "w")) == NULL)
90 return 2;
91
92 /* Selectively close various standard fds, to verify the child process is
93 not impacted by this. */
94 test = atoi (argv[2]);
95 switch (test)
96 {
97 case 0:
98 break;
99 case 1:
100 close (0);
101 break;
102 case 2:
103 close (1);
104 break;
105 case 3:
106 close (0);
107 close (1);
108 break;
109 case 4:
110 close (2);
111 break;
112 case 5:
113 close (0);
114 close (2);
115 break;
116 case 6:
117 close (1);
118 close (2);
119 break;
120 case 7:
121 close (0);
122 close (1);
123 close (2);
124 break;
125 default:
126 ASSERT (false);
127 }
128
129 /* Plug any file descriptor leaks inherited from outside world before
130 starting, so that child has a clean slate (at least for the fds that we
131 might be manipulating). */
132 for (fd = 3; fd < 7; fd++)
133 close (fd);
134
135 test_pipe (argv[1], test >= 4);
136
137 return 0;
138 }
139