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/* ISC license. */
#include <skalibs/sysdeps.h>
#include <errno.h>
#ifdef SKALIBS_HASPOSIXSPAWN
#include <signal.h>
#include <stdlib.h>
#include <spawn.h>
#include <skalibs/config.h>
#include <skalibs/djbunix.h>
pid_t child_spawn0 (char const *prog, char const *const *argv, char const *const *envp)
{
pid_t pid ;
posix_spawnattr_t attr ;
sigset_t set ;
int e ;
int nopath = !getenv("PATH") ;
#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
int p[2] ;
if (pipecoe(p) == -1) return 0 ;
#endif
e = posix_spawnattr_init(&attr) ;
if (e) goto err ;
sigemptyset(&set) ;
e = posix_spawnattr_setsigmask(&attr, &set) ;
if (e) goto errattr ;
e = posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSIGMASK) ;
if (e) goto errattr ;
if (nopath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0)) { e = errno ; goto errattr ; }
e = posix_spawnp(&pid, prog, 0, &attr, (char *const *)argv, (char *const *)envp) ;
if (nopath) unsetenv("PATH") ;
if (e) goto errattr ;
posix_spawnattr_destroy(&attr) ;
#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
return child_spawn_workaround(pid, p) ;
#else
return pid ;
#endif
errattr:
posix_spawnattr_destroy(&attr) ;
err:
#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
fd_close(p[1]) ;
fd_close(p[0]) ;
#endif
errno = e ;
return 0 ;
}
#else
#include <unistd.h>
#include <skalibs/allreadwrite.h>
#include <skalibs/sig.h>
#include <skalibs/djbunix.h>
#include <skalibs/exec.h>
pid_t child_spawn0 (char const *prog, char const *const *argv, char const *const *envp)
{
pid_t pid ;
int p[2] ;
char c ;
if (pipecoe(p) == -1) return 0 ;
pid = fork() ;
if (pid < 0)
{
fd_close(p[1]) ;
fd_close(p[0]) ;
return 0 ;
}
if (!pid)
{
sig_blocknone() ;
exec_ae(prog, argv, envp) ;
c = errno ;
fd_write(p[1], &c, 1) ;
_exit(127) ;
}
fd_close(p[1]) ;
p[1] = fd_read(p[0], &c, 1) ;
if (p[1] < 0)
{
fd_close(p[0]) ;
return 0 ;
}
fd_close(p[0]) ;
if (p[1])
{
wait_pid(pid, &p[0]) ;
errno = (unsigned char)c ;
return 0 ;
}
return pid ;
}
#endif
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