sandbox: move out of internal

Signed-off-by: Ophestra <cat@gensokyo.uk>

sandbox/syscall.go

@@ -0,0 +1,41 @@
+package sandbox
+
+import "syscall"
+
+const (
+	SUID_DUMP_DISABLE = iota
+	SUID_DUMP_USER
+)
+
+func SetDumpable(dumpable uintptr) error {
+	// linux/sched/coredump.h
+	if _, _, errno := syscall.RawSyscall(syscall.SYS_PRCTL, syscall.PR_SET_DUMPABLE, dumpable, 0); errno != 0 {
+		return errno
+	}
+
+	return nil
+}
+
+func SetPdeathsig(sig syscall.Signal) error {
+	if _, _, errno := syscall.RawSyscall(syscall.SYS_PRCTL, syscall.PR_SET_PDEATHSIG, uintptr(sig), 0); errno != 0 {
+		return errno
+	}
+
+	return nil
+}
+
+// IgnoringEINTR makes a function call and repeats it if it returns an
+// EINTR error. This appears to be required even though we install all
+// signal handlers with SA_RESTART: see #22838, #38033, #38836, #40846.
+// Also #20400 and #36644 are issues in which a signal handler is
+// installed without setting SA_RESTART. None of these are the common case,
+// but there are enough of them that it seems that we can't avoid
+// an EINTR loop.
+func IgnoringEINTR(fn func() error) error {
+	for {
+		err := fn()
+		if err != syscall.EINTR {
+			return err
+		}
+	}
+}