// Copyright 2017 The Chromium Authors // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef COMPONENTS_CBOR_WRITER_H_ #define COMPONENTS_CBOR_WRITER_H_ #include <stddef.h> #include <stdint.h> #include <optional> #include <vector> #include "base/memory/raw_ptr.h" #include "components/cbor/cbor_export.h" #include "components/cbor/float_conversions.h" #include "components/cbor/values.h" // A basic Concise Binary Object Representation (CBOR) encoder as defined by // https://tools.ietf.org/html/rfc7049. This is a generic encoder that supplies // canonical, well-formed CBOR values but does not guarantee their validity // (see https://tools.ietf.org/html/rfc7049#section-3.2). // Supported: // * Major types: // * 0: Unsigned integers, up to INT64_MAX. // * 1: Negative integers, to INT64_MIN. // * 2: Byte strings. // * 3: UTF-8 strings. // * 4: Arrays, with the number of elements known at the start. // * 5: Maps, with the number of elements known at the start // of the container. // * 7: Simple values. // // Unsupported: // * Indefinite-length encodings. // * Parsing. // // Requirements for canonical CBOR as suggested by RFC 7049 are: // 1) All major data types for the CBOR values must be as short as possible. // * Unsigned integer between 0 to 23 must be expressed in same byte as // the major type. // * 24 to 255 must be expressed only with an additional uint8_t. // * 256 to 65535 must be expressed only with an additional uint16_t. // * 65536 to 4294967295 must be expressed only with an additional // uint32_t. * The rules for expression of length in major types // 2 to 5 follow the above rule for integers. // 2) Keys in every map must be sorted (first by major type, then by key // length, then by value in byte-wise lexical order). // 3) Indefinite length items must be converted to definite length items. // 4) All maps must not have duplicate keys. // // Current implementation of Writer encoder meets all the requirements of // canonical CBOR. namespace cbor { class CBOR_EXPORT Writer { … }; } // namespace cbor #endif // COMPONENTS_CBOR_WRITER_H_