1 /* ISC license. */
2
3 #include <skalibs/sysdeps.h>
4 #include <errno.h>
5
6 #ifdef SKALIBS_HASPOSIXSPAWN
7
8 #include <signal.h>
9 #include <spawn.h>
10 #include <stdlib.h>
11
12 #include <skalibs/config.h>
13
child_spawn0(char const * prog,char const * const * argv,char const * const * envp)14 pid_t child_spawn0 (char const *prog, char const *const *argv, char const *const *envp)
15 {
16 pid_t pid ;
17 posix_spawnattr_t attr ;
18 int e ;
19 int nopath = !getenv("PATH") ;
20 e = posix_spawnattr_init(&attr) ;
21 if (e) goto err ;
22 {
23 sigset_t set ;
24 sigemptyset(&set) ;
25 e = posix_spawnattr_setsigmask(&attr, &set) ;
26 if (e) goto errattr ;
27 e = posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSIGMASK) ;
28 if (e) goto errattr ;
29 }
30 if (nopath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0)) { e = errno ; goto errattr ; }
31 e = posix_spawnp(&pid, prog, 0, &attr, (char *const *)argv, (char *const *)envp) ;
32 if (nopath) unsetenv("PATH") ;
33 posix_spawnattr_destroy(&attr) ;
34 if (e) goto err ;
35 return pid ;
36
37 errattr:
38 posix_spawnattr_destroy(&attr) ;
39 err:
40 errno = e ;
41 return 0 ;
42 }
43
44 #else
45
46 #include <unistd.h>
47 #include <string.h>
48
49 #include <skalibs/allreadwrite.h>
50 #include <skalibs/strerr2.h>
51 #include <skalibs/sig.h>
52 #include <skalibs/djbunix.h>
53 #include <skalibs/exec.h>
54
child_spawn0(char const * prog,char const * const * argv,char const * const * envp)55 pid_t child_spawn0 (char const *prog, char const *const *argv, char const *const *envp)
56 {
57 pid_t pid ;
58 int e ;
59 int p[2] ;
60 if (pipecoe(p) < 0) return 0 ;
61 pid = fork() ;
62 if (pid < 0)
63 {
64 fd_close(p[1]) ;
65 fd_close(p[0]) ;
66 return 0 ;
67 }
68 if (!pid)
69 {
70 size_t len = strlen(PROG) ;
71 char name[len + 9] ;
72 memcpy(name, PROG, len) ;
73 memcpy(name + len, " (child)", 9) ;
74 PROG = name ;
75 fd_close(p[0]) ;
76 sig_blocknone() ;
77 exec_ae(prog, argv, envp) ;
78 e = errno ;
79 fd_write(p[1], (char *)&e, sizeof(e)) ;
80 _exit(127) ;
81 }
82 fd_close(p[1]) ;
83 p[1] = fd_read(p[0], (char *)&e, sizeof(e)) ;
84 if (p[1] < 0)
85 {
86 fd_close(p[0]) ;
87 return 0 ;
88 }
89 fd_close(p[0]) ;
90 if (p[1] == sizeof(e))
91 {
92 wait_pid(pid, &p[0]) ;
93 errno = e ;
94 return 0 ;
95 }
96 return pid ;
97 }
98
99 #endif
100