2 files changed, 26 insertions, 0 deletions
diff --git a/src/libs6/deps-lib/s6 b/src/libs6/deps-lib/s6
index 23ca024..65062e1 100644
--- a/src/libs6/deps-lib/s6
+++ b/src/libs6/deps-lib/s6
@@ -25,6 +25,7 @@ s6_accessrules_uidgid_cdb.o
 s6_accessrules_uidgid_fs.o
 s6_supervise_lock.o
 s6_supervise_lock_mode.o
+s6_svc_ok.o
 s6_svc_write.o
 s6_svc_writectl.o
 s6_svstatus_pack.o
diff --git a/src/libs6/s6_svc_ok.c b/src/libs6/s6_svc_ok.c
new file mode 100644
index 0000000..37c317c
--- /dev/null
+++ b/src/libs6/s6_svc_ok.c
@@ -0,0 +1,25 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/djbunix.h>
+#include <s6/s6-supervise.h>
+
+int s6_svc_ok (char const *dir)
+{
+  int fd ;
+  unsigned int dirlen = str_len(dir) ;
+  char fn[dirlen + 9 + sizeof(S6_SUPERVISE_CTLDIR)] ;
+  byte_copy(fn, dirlen, dir) ;
+  fn[dirlen] = '/' ;
+  byte_copy(fn + dirlen + 1, sizeof(S6_SUPERVISE_CTLDIR) - 1, S6_SUPERVISE_CTLDIR) ;
+  byte_copy(fn + dirlen + sizeof(S6_SUPERVISE_CTLDIR), 9, "/control") ;
+  fd = open_write(fn) ;
+  if (fd < 0)
+  {
+    if ((errno == ENXIO) || (errno == ENOENT)) return 0 ;
+    else return -1 ;
+  }
+  fd_close(fd) ;
+  return 1 ;
+}