-extern bool base64_decode (const char *restrict in, size_t inlen,
- char *restrict out, size_t *outlen);
+extern void base64_decode_ctx_init (struct base64_decode_context *ctx);
+
+extern bool base64_decode_ctx (struct base64_decode_context *ctx,
+ const char *restrict in, size_t inlen,
+ char *restrict out, size_t *outlen);
+
+extern bool base64_decode_alloc_ctx (struct base64_decode_context *ctx,
+ const char *in, size_t inlen,
+ char **out, size_t *outlen);
+
+#define base64_decode(in, inlen, out, outlen) \
+ base64_decode_ctx (NULL, in, inlen, out, outlen)