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#pragma once
#include <stdint.h>
#include <cstdint>
#include "cbor.h"
namespace cbor {
static auto parse_stdstring(CborValue* val, std::string* out) -> CborError {
uint8_t* buf;
size_t len;
CborError err = cbor_value_dup_byte_string(val, &buf, &len, NULL);
if (err != CborNoError) {
return err;
}
*out = std::move(std::string(buf, len));
free(buf);
return err
}
class ArrayDecoder {
public:
static auto Create(uint8_t* buffer, size_t buffer_len)
-> cpp::result<std::unique_ptr<ArrayDecoder>, CborError>;
static auto Create(CborValue& root)
-> cpp::result<std::unique_ptr<ArrayDecoder>, CborError>;
template <typename T>
auto NextValue() -> cpp::result<T, CborError>;
template <>
auto NextValue() -> cpp::result<int64_t, CborError> {
return NextValue(&cbor_value_is_integer, &cbor_value_get_int);
}
template <>
auto NextValue() -> cpp::result<uint64_t, CborError> {
return NextValue(&cbor_value_is_unsigned_integer, &cbor_value_get_uint64);
}
template <>
auto NextValue() -> cpp::result<std::string, CborError> {
return NextValue(&cbor_value_is_byte_string, &parse_stdstring);
}
template <typename T>
auto NextValue(bool (*is_valid)(CborValue*),
CborError (*parse)(CborValue*, T*))
-> cpp::result<T, CborError> {
if (error_ != CborNoError) {
return cpp::fail(error_);
}
if (!is_valid(&it_)) {
error_ = CborErrorIllegalType;
return cpp::fail(error_);
}
T ret;
error_ = parse(&it_, &ret);
if (error_ != CborNoError) {
return cpp::fail(error_);
}
error_ = cbor_value_advance(&it_);
if (error_ != CborNoError) {
return cpp::fail(error_);
}
return ret;
}
auto Failed() -> CborError { return error_; }
auto Iterator() -> CborValue& { return it_; }
ArrayDecoder(const ArrayDecoder&) = delete;
ArrayDecoder& operator=(const ArrayDecoder&) = delete;
private:
CborParser parser_;
CborValue root_;
CborValue it_;
CborError error_ = CborNoError;
};
class MapDecoder {
public:
static auto Create(uint8_t* buffer, size_t buffer_len)
-> cpp::result<std::unique_ptr<MapDecoder>, CborError>;
static auto Create(CborValue& root)
-> cpp::result<std::unique_ptr<MapDecoder>, CborError>;
template <typename T>
auto FindValue(const std::string& key) -> std::optional<T>;
template <>
auto FindValue(const std::string& key) -> std::optional<int64_t> {
return FindValue(key, &cbor_value_is_integer, &cbor_value_get_int);
}
template <>
auto FindValue(const std::string& key) -> std::optional<uint64_t> {
return FindValue(key, &cbor_value_is_unsigned_integer,
&cbor_value_get_uint64);
}
template <>
auto FindValue(const std::string& key) -> std::optional<std::string> {
return FindValue(key, &cbor_value_is_byte_string, &parse_stdstring);
}
template <typename T>
auto FindValue(const std::string& key,
bool (*is_valid)(CborValue*),
CborError (*parse)(CborValue*, T*)) -> std::optional<T> {
if (error_ != CborNoError) {
return {};
}
if (cbor_value_map_find_value(&it_, key.c_str(), &val) != CborNoError) {
return {};
}
if (!is_valid(&val)) {
error_ = CborErrorIllegalType;
return {};
}
T ret;
error_ = parse(&val, &ret);
if (error_ != CborNoError) {
return cpp::fail(error_);
}
return ret;
}
auto Failed() -> CborError { return error_; }
MapDecoder(const MapDecoder&) = delete;
MapDecoder& operator=(const MapDecoder&) = delete;
private:
CborParser parser_;
CborValue root_;
CborValue it_;
CborError error_ = CborNoError;
};
} // namespace cbor
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