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

fusl/include/strings.h

+#ifndef _STRINGS_H
+#define _STRINGS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+#define __NEED_size_t
+#define __NEED_locale_t
+#include <bits/alltypes.h>
+
+#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE) || defined(_POSIX_SOURCE) \
+ || (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE+0 < 200809L) \
+ || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE+0 < 700)
+int bcmp (const void *, const void *, size_t);
+void bcopy (const void *, void *, size_t);
+void bzero (void *, size_t);
+char *index (const char *, int);
+char *rindex (const char *, int);
+#endif
+
+#if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)  || defined(_BSD_SOURCE)
+int ffs (int);
+int ffsl (long);
+int ffsll (long long);
+#endif
+
+int strcasecmp (const char *, const char *);
+int strncasecmp (const char *, const char *, size_t);
+
+int strcasecmp_l (const char *, const char *, locale_t);
+int strncasecmp_l (const char *, const char *, size_t, locale_t);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif