Add a "fork" of musl as //fusl.

fusl/src/ipc/semget.c

Index: fusl/src/ipc/semget.c
diff --git a/fusl/src/ipc/semget.c b/fusl/src/ipc/semget.c
new file mode 100644
index 0000000000000000000000000000000000000000..c4a559db1b0ec1316dc2fa9bc47a538ea552d94a
--- /dev/null
+++ b/fusl/src/ipc/semget.c
@@ -0,0 +1,19 @@
+#include <sys/sem.h>
+#include <limits.h>
+#include <errno.h>
+#include "syscall.h"
+#include "ipc.h"
+
+int semget(key_t key, int n, int fl)
+{
+	/* The kernel uses the wrong type for the sem_nsems member
+	 * of struct semid_ds, and thus might not check that the
+	 * n fits in the correct (per POSIX) userspace type, so
+	 * we have to check here. */
+	if (n > USHRT_MAX) return __syscall_ret(-EINVAL);
+#ifdef SYS_semget
+	return syscall(SYS_semget, key, n, fl);
+#else
+	return syscall(SYS_ipc, IPCOP_semget, key, n, fl);
+#endif
+}