1 files changed, 104 insertions, 0 deletions
diff --git a/src/tls/s6tls_io_spawn.c b/src/tls/s6tls_io_spawn.c
new file mode 100644
index 0000000..e2d589a
--- /dev/null
+++ b/src/tls/s6tls_io_spawn.c
@@ -0,0 +1,104 @@
+/* ISC license. */
+
+#include <skalibs/sysdeps.h>
+
+#include <skalibs/djbunix.h>
+
+#include "s6tls-internal.h"
+
+#ifdef SKALIBS_HASPOSIXSPAWN
+
+#include <errno.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <spawn.h>
+
+#include <skalibs/config.h>
+#include <skalibs/posixplz.h>
+
+pid_t s6tls_io_spawn (char const *const *argv, int const p[4][2])
+{
+  pid_t pid ;
+  posix_spawn_file_actions_t actions ;
+  int e ;
+  int nopath = !getenv("PATH") ;
+#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
+  int eep[2] ;
+  if (pipecoe(eep) == -1) return 0 ;
+#endif
+  e = posix_spawn_file_actions_init(&actions) ;
+  if (e) goto err ;
+  e = posix_spawn_file_actions_addclose(&actions, p[0][1]) ;
+  if (e) goto erractions ;
+  e = posix_spawn_file_actions_addclose(&actions, p[1][0]) ;
+  if (e) goto erractions ;
+  e = posix_spawn_file_actions_addclose(&actions, p[2][0]) ;
+  if (e) goto erractions ;
+  if (p[3][0] >= 0)
+  {
+    e = posix_spawn_file_actions_adddup2(&actions, p[3][0], 0) ;
+    if (e) goto erractions ;
+    e = posix_spawn_file_actions_addclose(&actions, p[3][0]) ;
+    if (e) goto erractions ;
+  }
+  if (p[3][1] >= 0)
+  {
+    e = posix_spawn_file_actions_adddup2(&actions, p[3][1], 1) ;
+    if (e) goto erractions ;
+    e = posix_spawn_file_actions_addclose(&actions, p[3][1]) ;
+    if (e) goto erractions ;
+  }
+
+  if (nopath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0)) { e = errno ; goto erractions ; }
+  e = posix_spawnp(&pid, argv[0], &actions, 0, (char *const *)argv, environ) ;
+  if (nopath) unsetenv("PATH") ;
+  if (e) goto erractions ;
+
+  posix_spawn_file_actions_destroy(&actions) ;
+#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
+  return child_spawn_workaround(pid, eep) ;
+#else
+  return pid ;
+#endif
+
+ erractions:
+  posix_spawn_file_actions_destroy(&actions) ;
+ err:
+#ifdef SKALIBS_HASPOSIXSPAWNEARLYRETURN
+  fd_close(eep[1]) ;
+  fd_close(eep[0]) ;
+#endif
+  errno = e ;
+  return 0 ;
+}
+
+#else
+
+#include <string.h>
+
+#include <skalibs/strerr.h>
+#include <skalibs/exec.h>
+
+pid_t s6tls_io_spawn (char const *const *argv, int const p[4][2])
+{
+  pid_t pid = fork() ;
+  if (pid == -1) return 0 ;
+  if (!pid)
+  {
+    size_t proglen = strlen(PROG) ;
+    char newprog[proglen + 9] ;
+    memcpy(newprog, PROG, proglen) ;
+    memcpy(newprog, " (child)", 9) ;
+    PROG = newprog ;
+    fd_close(p[0][1]) ;
+    fd_close(p[1][0]) ;
+    fd_close(p[2][0]) ;
+    if ((p[3][0] >= 0 && fd_move(0, p[3][0]) == -1)
+     || (p[3][1] >= 0 && fd_move(1, p[3][1]) == -1))
+      strerr_diefu1sys(111, "move network fds to stdin/stdout") ;
+    xexec(argv) ;
+  }
+  return pid ;
+}
+
+#endif