1 files changed, 65 insertions, 0 deletions
diff --git a/src/minutils/s6-umount.c b/src/minutils/s6-umount.c
new file mode 100644
index 0000000..966b455
--- /dev/null
+++ b/src/minutils/s6-umount.c
@@ -0,0 +1,65 @@
+/* ISC license. */
+
+#include <sys/mount.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/buffer.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/skamisc.h>
+
+#define USAGE "s6-umount mountpoint <or> s6-umount -a"
+
+#define BUFSIZE 4096
+#define MAXLINES 512
+
+static int umountall ( )
+{
+  stralloc mountpoints[MAXLINES] ;
+  char buf[BUFSIZE+1] ;
+  buffer b ;
+  stralloc sa = STRALLOC_ZERO ;
+  unsigned int line = 0 ;
+  int e = 0 ;
+  int r ;
+  int fd = open_readb("/proc/mounts") ;
+  if (fd < 0) strerr_diefu1sys(111, "open /proc/mounts") ;
+  byte_zero(mountpoints, sizeof(mountpoints)) ;
+  buffer_init(&b, &buffer_read, fd, buf, BUFSIZE+1) ;
+  for (;;)
+  {
+    unsigned int n, p ;
+    if (line >= MAXLINES) strerr_dief1x(111, "/proc/mounts too big") ;
+    sa.len = 0 ;
+    r = skagetln(&b, &sa, '\n') ;
+    if (r <= 0) break ;
+    p = byte_chr(sa.s, sa.len, ' ') ;
+    if (p >= sa.len) strerr_dief1x(111, "bad /proc/mounts format") ;
+    p++ ;
+    n = byte_chr(sa.s + p, sa.len - p, ' ') ;
+    if (n == sa.len - p) strerr_dief1x(111, "bad /proc/mounts format") ;
+    if (!stralloc_catb(&mountpoints[line], sa.s + p, n) || !stralloc_0(&mountpoints[line]))
+      strerr_diefu1sys(111, "store mount point") ;
+    line++ ;
+  }
+  fd_close(fd) ;
+  stralloc_free(&sa) ;
+  if (r < 0) strerr_diefu1sys(111, "read /proc/mounts") ;
+  while (line--)
+    if (umount(mountpoints[line].s) == -1)
+    {
+      e++ ;
+      strerr_warnwu2sys("umount ", mountpoints[line].s) ;
+    }
+  return e ;
+}
+
+int main (int argc, char const *const *argv)
+{
+  PROG = "s6-umount" ;
+  if (argc < 2) strerr_dieusage(100, USAGE) ;
+  if ((argv[1][0] == '-') && (argv[1][1] == 'a') && !argv[1][2])
+    return umountall() ;
+  if (umount(argv[1]) == -1) strerr_diefu2sys(111, "umount ", argv[1]) ;
+  return 0 ;
+}