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
|
/* ISC license. */
/* MT-unsafe */
#include <skalibs/sysdeps.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/wait.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#ifdef SKALIBS_HASPOSIXSPAWN
#include <stdlib.h>
#include <spawn.h>
#include <skalibs/config.h>
#else
#include <string.h>
#include <skalibs/allreadwrite.h>
#include <skalibs/sig.h>
#include <skalibs/strerr2.h>
#include <skalibs/exec.h>
#endif
#include <skalibs/djbunix.h>
pid_t child_spawn2 (char const *prog, char const *const *argv, char const *const *envp, int *fds)
{
pid_t pid ;
#ifdef SKALIBS_HASPOSIXSPAWN
posix_spawn_file_actions_t actions ;
posix_spawnattr_t attr ;
int e ;
#else
int syncpipe[2] ;
#endif
int p[2][2] ;
if (pipe(p[0]) < 0) return 0 ;
if (ndelay_on(p[0][0]) < 0 || coe(p[0][0]) < 0 || pipe(p[1]) < 0) goto errp ;
if (ndelay_on(p[1][1]) < 0 || coe(p[1][1]) < 0) goto errp1 ;
#ifdef SKALIBS_HASPOSIXSPAWN
e = posix_spawnattr_init(&attr) ;
if (e) goto erre ;
{
sigset_t set ;
sigemptyset(&set) ;
e = posix_spawnattr_setsigmask(&attr, &set) ;
if (e) goto errattr ;
e = posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSIGMASK) ;
if (e) goto errattr ;
}
e = posix_spawn_file_actions_init(&actions) ;
if (e) goto errattr ;
if (p[1][0] != fds[0])
{
e = posix_spawn_file_actions_adddup2(&actions, p[1][0], fds[0]) ;
if (e) goto erractions ;
e = posix_spawn_file_actions_addclose(&actions, p[1][0]) ;
if (e) goto erractions ;
}
if (p[0][1] != fds[1])
{
e = posix_spawn_file_actions_adddup2(&actions, p[0][1], fds[1]) ;
if (e) goto erractions ;
e = posix_spawn_file_actions_addclose(&actions, p[0][1]) ;
if (e) goto erractions ;
}
{
int nopath = !getenv("PATH") ;
if (nopath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0))
{
e = errno ; goto erractions ;
}
e = posix_spawnp(&pid, prog, &actions, &attr, (char *const *)argv, (char *const *)envp) ;
if (nopath) unsetenv("PATH") ;
if (e) goto erractions ;
}
posix_spawn_file_actions_destroy(&actions) ;
posix_spawnattr_destroy(&attr) ;
#else
if (pipecoe(syncpipe) < 0) goto errp1 ;
pid = fork() ;
if (pid < 0) goto errsp ;
else if (!pid)
{
size_t len = strlen(PROG) ;
char name[len + 9] ;
memcpy(name, PROG, len) ;
memcpy(name + len, " (child)", 9) ;
PROG = name ;
if (fd_move2(fds[0], p[1][0], fds[1], p[0][1]) < 0) goto syncdie ;
sig_blocknone() ;
exec_ae(prog, argv, envp) ;
syncdie:
{
char c = errno ;
fd_write(syncpipe[1], &c, 1) ;
}
_exit(127) ;
}
fd_close(syncpipe[1]) ;
{
char c ;
syncpipe[1] = fd_read(syncpipe[0], &c, 1) ;
if (syncpipe[1])
{
int e = c ;
if (syncpipe[1] < 0) e = errno ;
if (wait_pid(pid, &syncpipe[1]) < 0) e = errno ;
errno = e ;
goto errsp0 ;
}
}
fd_close(syncpipe[0]) ;
#endif
fd_close(p[0][1]) ; fds[0] = p[0][0] ;
fd_close(p[1][0]) ; fds[1] = p[1][1] ;
return pid ;
#ifdef SKALIBS_HASPOSIXSPAWN
erractions:
posix_spawn_file_actions_destroy(&actions) ;
errattr:
posix_spawnattr_destroy(&attr) ;
erre:
errno = e ;
#endif
#ifndef SKALIBS_HASPOSIXSPAWN
errsp:
fd_close(syncpipe[1]) ;
errsp0:
fd_close(syncpipe[0]) ;
#endif
errp1:
fd_close(p[1][1]) ;
fd_close(p[1][0]) ;
errp:
fd_close(p[0][1]) ;
fd_close(p[0][0]) ;
return 0 ;
}
|
