--- /dev/null
+/*
+ *
+ * Copyright 2016 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_SLICE_PERCENT_ENCODING_H
+#define GRPC_CORE_LIB_SLICE_PERCENT_ENCODING_H
+
+/* Percent encoding and decoding of slices.
+ Transforms arbitrary strings into safe-for-transmission strings by using
+ variants of percent encoding (RFC 3986).
+ Two major variants are supplied: one that strictly matches URL encoding,
+ and another which applies percent encoding only to non-http2 header
+ bytes (the 'compatible' variant) */
+
+#include <grpc/support/port_platform.h>
+
+#include <stdbool.h>
+
+#include <grpc/slice.h>
+
+/* URL percent encoding spec bitfield (usabel as 'unreserved_bytes' in
+ grpc_percent_encode_slice, grpc_strict_percent_decode_slice).
+ Flags [A-Za-z0-9-_.~] as unreserved bytes for the percent encoding routines
+ */
+extern const uint8_t grpc_url_percent_encoding_unreserved_bytes[256 / 8];
+/* URL percent encoding spec bitfield (usabel as 'unreserved_bytes' in
+ grpc_percent_encode_slice, grpc_strict_percent_decode_slice).
+ Flags ascii7 non-control characters excluding '%' as unreserved bytes for the
+ percent encoding routines */
+extern const uint8_t grpc_compatible_percent_encoding_unreserved_bytes[256 / 8];
+
+/* Percent-encode a slice, returning the new slice (this cannot fail):
+ unreserved_bytes is a bitfield indicating which bytes are considered
+ unreserved and thus do not need percent encoding */
+grpc_slice grpc_percent_encode_slice(const grpc_slice& slice,
+ const uint8_t* unreserved_bytes);
+/* Percent-decode a slice, strictly.
+ If the input is legal (contains no unreserved bytes, and legal % encodings),
+ returns true and sets *slice_out to the decoded slice.
+ If the input is not legal, returns false and leaves *slice_out untouched.
+ unreserved_bytes is a bitfield indicating which bytes are considered
+ unreserved and thus do not need percent encoding */
+bool grpc_strict_percent_decode_slice(const grpc_slice& slice_in,
+ const uint8_t* unreserved_bytes,
+ grpc_slice* slice_out);
+/* Percent-decode a slice, permissively.
+ If a % triplet can not be decoded, pass it through verbatim.
+ This cannot fail. */
+grpc_slice grpc_permissive_percent_decode_slice(const grpc_slice& slice_in);
+
+#endif /* GRPC_CORE_LIB_SLICE_PERCENT_ENCODING_H */