Support FreeBSD on pkg/mount

Docker-DCO-1.1-Signed-off-by: Kato Kazuyoshi <kato.kazuyoshi@gmail.com> (github: kzys)

mount/mountinfo_freebsd.go

@@ -0,0 +1,38 @@
+package mount
+
+/*
+#include <sys/param.h>
+#include <sys/ucred.h>
+#include <sys/mount.h>
+*/
+import "C"
+
+import (
+	"fmt"
+	"reflect"
+	"unsafe"
+)
+
+// Parse /proc/self/mountinfo because comparing Dev and ino does not work from bind mounts
+func parseMountTable() ([]*MountInfo, error) {
+	var rawEntries *C.struct_statfs
+
+	count := int(C.getmntinfo(&rawEntries, C.MNT_WAIT))
+	if count == 0 {
+		return nil, fmt.Errorf("Failed to call getmntinfo")
+	}
+
+	var entries []C.struct_statfs
+	header := (*reflect.SliceHeader)(unsafe.Pointer(&entries))
+	header.Cap = count
+	header.Len = count
+	header.Data = uintptr(unsafe.Pointer(rawEntries))
+
+	var out []*MountInfo
+	for _, entry := range entries {
+		var mountinfo MountInfo
+		mountinfo.Mountpoint = C.GoString(&entry.f_mntonname[0])
+		out = append(out, &mountinfo)
+	}
+	return out, nil
+}