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
|
/* $OpenPackages$ */
/* $OpenBSD: cmd_exec.c,v 1.3 2002/08/05 17:04:36 millert Exp $ */
/*
* Copyright (c) 2001 Marc Espie.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OPENBSD
* PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include "config.h"
#include "defines.h"
#include "cmd_exec.h"
#include "buf.h"
#include "memory.h"
#include "pathnames.h"
char *
Cmd_Exec(cmd, err)
const char *cmd;
char **err;
{
char *args[4]; /* Args for invoking the shell */
int fds[2]; /* Pipe streams */
pid_t cpid; /* Child PID */
pid_t pid; /* PID from wait() */
char *result; /* Result */
int status; /* Command exit status */
BUFFER buf; /* Buffer to store the result. */
char *cp; /* Pointer into result. */
ssize_t cc; /* Characters read from pipe. */
size_t length; /* Total length of result. */
*err = NULL;
/* Set up arguments for the shell. */
args[0] = "sh";
args[1] = "-c";
args[2] = (char *)cmd;
args[3] = NULL;
/* Open a pipe for retrieving shell's output. */
if (pipe(fds) == -1) {
*err = "Couldn't create pipe for \"%s\"";
goto bad;
}
/* Fork */
switch (cpid = fork()) {
case 0:
/* Close input side of pipe */
(void)close(fds[0]);
/* Duplicate the output stream to the shell's output, then
* shut the extra thing down. Note we don't fetch the error
* stream: user can use redirection to grab it as this goes
* through /bin/sh.
*/
if (fds[1] != 1) {
(void)dup2(fds[1], 1);
(void)close(fds[1]);
}
(void)execv(_PATH_BSHELL, args);
_exit(1);
/*NOTREACHED*/
case -1:
*err = "Couldn't exec \"%s\"";
goto bad;
default:
/* No need for the writing half. */
(void)close(fds[1]);
Buf_Init(&buf, MAKE_BSIZE);
do {
char grab[BUFSIZ];
cc = read(fds[0], grab, sizeof(grab));
if (cc > 0)
Buf_AddChars(&buf, cc, grab);
}
while (cc > 0 || (cc == -1 && errno == EINTR));
/* Close the input side of the pipe. */
(void)close(fds[0]);
/* Wait for the child to exit. */
while ((pid = wait(&status)) != cpid && pid >= 0)
continue;
if (cc == -1)
*err = "Couldn't read shell's output for \"%s\"";
if (status)
*err = "\"%s\" returned non-zero status";
length = Buf_Size(&buf);
result = Buf_Retrieve(&buf);
/* The result is null terminated, Convert newlines to spaces. */
cp = result + length - 1;
if (*cp == '\n')
/* A final newline is just stripped. */
*cp-- = '\0';
while (cp >= result) {
if (*cp == '\n')
*cp = ' ';
cp--;
}
break;
}
return result;
bad:
return estrdup("");
}
|
