-int bcmp __P((const void *, const void *, size_t));
-int ffs __P((int));
-int locc __P((int, char *, u_int));
-u_long random __P((void));
-char *rindex __P((const char *, int));
-int scanc __P((u_int, u_char *, u_char *, int));
-int skpc __P((int, int, char *));
-char *strcat __P((char *, const char *));
-char *strcpy __P((char *, const char *));
-size_t strlen __P((const char *));
-char *strncpy __P((char *, const char *, size_t));
-long strtol __P((const char*, char **, int));
+extern int ffs(int);
+extern int ffsll(unsigned long long);
+extern int fls(int);
+extern int flsll(unsigned long long);
+extern u_int32_t random(void);
+extern int scanc(u_int, u_char *, const u_char *, int);
+extern int skpc(int, int, char *);
+extern long strtol(const char*, char **, int);
+extern u_long strtoul(const char *, char **, int);
+extern quad_t strtoq(const char *, char **, int);
+extern u_quad_t strtouq(const char *, char **, int);
+extern char *strsep(char **, const char *);
+extern void *memchr(const void *, int, size_t);
+extern void url_decode(char *str);
+
+int snprintf(char *, size_t, const char *, ...) __printflike(3,4);
+
+/* sprintf() is being deprecated. Please use snprintf() instead. */
+int sprintf(char *bufp, const char *, ...) __deprecated __printflike(2,3);
+int sscanf(const char *, char const *, ...) __scanflike(2,3);
+int printf(const char *, ...) __printflike(1,2);
+
+#if KERNEL_PRIVATE
+int _consume_printf_args(int, ...);
+#endif
+
+#if CONFIG_NO_PRINTF_STRINGS
+#if KERNEL_PRIVATE
+#define printf(x, ...) _consume_printf_args( 0, ## __VA_ARGS__ )
+#else
+#define printf(x, ...) do {} while (0)
+#endif
+#endif
+
+uint16_t crc16(uint16_t crc, const void *bufp, size_t len);
+uint32_t crc32(uint32_t crc, const void *bufp, size_t len);
+
+#if XNU_KERNEL_PRIVATE
+#if KASAN
+uint16_t __nosan_crc16(uint16_t crc, const void *bufp, size_t len);
+#else
+static inline uint16_t
+__nosan_crc16(uint16_t crc, const void *bufp, size_t len) { return crc16(crc, bufp, len); }
+#endif
+#endif
+
+int copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *done);
+int copyinstr(const user_addr_t uaddr, void *kaddr, size_t len, size_t *done);
+int copyoutstr(const void *kaddr, user_addr_t udaddr, size_t len, size_t *done);
+#if XNU_KERNEL_PRIVATE
+extern int copyin_word(const user_addr_t user_addr, uint64_t *kernel_addr, vm_size_t nbytes);
+#endif
+
+int vsscanf(const char *, char const *, va_list);
+
+extern int vprintf(const char *, va_list) __printflike(1,0);
+extern int vsnprintf(char *, size_t, const char *, va_list) __printflike(3,0);
+
+#if XNU_KERNEL_PRIVATE
+extern int vprintf_log_locked(const char *, va_list) __printflike(1,0);
+extern void osobject_retain(void * object);
+extern void osobject_release(void * object);
+#endif
+
+/* vsprintf() is being deprecated. Please use vsnprintf() instead. */
+extern int vsprintf(char *bufp, const char *, va_list) __deprecated __printflike(2,0);
+
+#ifdef KERNEL_PRIVATE
+#ifdef __arm__
+void flush_inner_dcaches(void);
+void clean_inner_dcaches(void);
+#endif
+extern void invalidate_icache(vm_offset_t, unsigned, int);
+extern void flush_dcache(vm_offset_t, unsigned, int);
+#else
+extern void invalidate_icache(vm_offset_t, unsigned, int);
+extern void flush_dcache(vm_offset_t, unsigned, int);
+#endif
+extern void invalidate_icache64(addr64_t, unsigned, int);
+extern void flush_dcache64(addr64_t, unsigned, int);
+
+
+static inline int
+clz(unsigned int num)
+{
+#if (__arm__ || __arm64__)
+ // On ARM, clz(0) is defined to return number of bits in the input type
+ return __builtin_clz(num);
+#else
+ // On Intel, clz(0) is undefined
+ return num ? __builtin_clz(num) : sizeof(num) * CHAR_BIT;
+#endif
+}
+
+#if XNU_KERNEL_PRIVATE
+
+/*
+ * Define a function that for whatever reason needs to exist, but must never be
+ * called.
+ */
+#define UNSUPPORTED_API(funcname, ...) \
+ _Pragma("clang diagnostic push") \
+ _Pragma("clang diagnostic ignored \"-Wunused-parameter\"") \
+ funcname(__VA_ARGS__) { panic(__func__ ": unsupported API\n"); } \
+ _Pragma("clang diagnostic pop")
+
+#endif
+