+int b64_encode(const void *src, size_t src_len,
+ void *dest, size_t dest_len);
+
+int b64_decode(const void *src, void *dest, size_t dest_len);
+
+#define B64_ENCODE_LEN(_len) ((((_len) + 2) / 3) * 4 + 1)
+#define B64_DECODE_LEN(_len) (((_len) / 4) * 3 + 1)
+
+static inline unsigned int cbuf_order(unsigned int x)
+{
+ return 32 - __builtin_clz(x - 1);
+}
+
+static inline unsigned long cbuf_size(int order)
+{
+ unsigned long page_size = sysconf(_SC_PAGESIZE);
+ unsigned long ret = 1ULL << order;
+
+ if (ret < page_size)
+ ret = page_size;
+
+ return ret;
+}
+
+void *cbuf_alloc(unsigned int order);
+void cbuf_free(void *ptr, unsigned int order);
+