gba-link-connection/lib/LinkWirelessOpenSDK.hpp
2025-01-01 20:00:16 -03:00

424 lines
14 KiB
C++

#ifndef LINK_WIRELESS_OPEN_SDK_H
#define LINK_WIRELESS_OPEN_SDK_H
// --------------------------------------------------------------------------
// An open-source implementation of the "official" Wireless Adapter protocol.
// --------------------------------------------------------------------------
// - Advanced usage only!
// - You only need this if you want to interact with N software.
// --------------------------------------------------------------------------
#ifndef LINK_DEVELOPMENT
#pragma GCC system_header
#endif
#include "_link_common.hpp"
#include "LinkRawWireless.hpp"
static volatile char VERSION[] = "LinkWirelessOpenSDK/v7.1.0";
/**
* @brief An open-source implementation of the "official" Wireless Adapter
* protocol.
* \warning Advanced usage only!
* \warning You only need this if you want to interact with N software.
*/
class LinkWirelessOpenSDK {
private:
using u32 = unsigned int;
using u16 = unsigned short;
using u8 = unsigned char;
public:
static constexpr int MAX_TRANSFER_WORDS = 23;
static constexpr int MAX_TRANSFER_BYTES_SERVER = 87;
static constexpr int MAX_TRANSFER_BYTES_CLIENT = 16;
static constexpr int HEADER_SIZE_SERVER = 3;
static constexpr int HEADER_SIZE_CLIENT = 2;
static constexpr int HEADER_MASK_SERVER = (1 << (HEADER_SIZE_SERVER * 8)) - 1;
static constexpr int HEADER_MASK_CLIENT = (1 << (HEADER_SIZE_CLIENT * 8)) - 1;
static constexpr int MAX_PAYLOAD_SERVER =
MAX_TRANSFER_BYTES_SERVER - HEADER_SIZE_SERVER;
static constexpr int MAX_PAYLOAD_CLIENT =
MAX_TRANSFER_BYTES_CLIENT - HEADER_SIZE_CLIENT;
static constexpr int MAX_PACKETS_SERVER =
MAX_TRANSFER_BYTES_SERVER / HEADER_SIZE_SERVER;
static constexpr int MAX_PACKETS_CLIENT =
MAX_TRANSFER_BYTES_CLIENT / HEADER_SIZE_CLIENT;
public:
template <class T>
struct SendBuffer {
T header;
std::array<u32, MAX_TRANSFER_WORDS> data;
u32 dataSize = 0;
u32 totalByteCount = 0;
};
enum CommState : unsigned int {
OFF = 0,
STARTING = 1,
COMMUNICATING = 2,
ENDING = 3,
DIRECT = 4
};
struct SequenceNumber {
u32 n = 0;
u32 phase = 0;
CommState commState = OFF;
static SequenceNumber fromPacketId(u32 packetId) {
return SequenceNumber{.n = ((packetId + 4) / 4) % 4,
packetId % 4,
.commState = COMMUNICATING};
}
bool operator==(const SequenceNumber& other) {
return n == other.n && phase == other.phase &&
commState == other.commState;
}
};
struct ServerSDKHeader {
unsigned int payloadSize : 7;
unsigned int _unused_ : 2;
unsigned int phase : 2;
unsigned int n : 2;
unsigned int isACK : 1;
CommState commState : 4;
unsigned int targetSlots : 4;
SequenceNumber sequence() {
return SequenceNumber{.n = n, .phase = phase, .commState = commState};
}
};
union ServerSDKHeaderSerializer {
ServerSDKHeader asStruct;
u32 asInt;
};
struct ServerPacket {
ServerSDKHeader header;
u8 payload[MAX_PAYLOAD_SERVER];
};
struct ServerResponse {
ServerPacket packets[MAX_PACKETS_SERVER];
u32 packetsSize = 0;
};
struct ParentData {
ServerResponse response;
};
struct ClientSDKHeader {
unsigned int payloadSize : 5;
unsigned int phase : 2;
unsigned int n : 2;
unsigned int isACK : 1;
CommState commState : 4;
SequenceNumber sequence() {
return SequenceNumber{.n = n, .phase = phase, .commState = commState};
}
};
union ClientSDKHeaderSerializer {
ClientSDKHeader asStruct;
u16 asInt;
};
struct ClientPacket {
ClientSDKHeader header;
u8 payload[MAX_PAYLOAD_CLIENT];
};
struct ClientResponse {
ClientPacket packets[MAX_PACKETS_CLIENT];
u32 packetsSize = 0;
};
struct ChildrenData {
ClientResponse responses[4];
};
/**
* @brief Parses the `response` and returns a struct containing all the
* received packets from the connected clients.
* @param response The response to be parsed.
*/
[[nodiscard]]
ChildrenData getChildrenData(LinkRawWireless::ReceiveDataResponse response) {
u8* buffer = (u8*)response.data;
u32 cursor = 0;
ChildrenData childrenData;
if (response.sentBytes[1] + response.sentBytes[2] + response.sentBytes[3] +
response.sentBytes[4] >
response.dataSize * 4)
return childrenData;
for (u32 i = 1; i < LINK_RAW_WIRELESS_MAX_PLAYERS; i++) {
ClientResponse* clientResponse = &childrenData.responses[i - 1];
u32 remainingBytes = response.sentBytes[i];
while (remainingBytes >= HEADER_SIZE_CLIENT) {
ClientPacket* packet =
&clientResponse->packets[clientResponse->packetsSize];
u32 headerInt = *((u16*)(buffer + cursor));
packet->header = parseClientHeader(headerInt);
cursor += HEADER_SIZE_CLIENT;
remainingBytes -= HEADER_SIZE_CLIENT;
if (packet->header.payloadSize > 0 &&
packet->header.payloadSize <= MAX_PAYLOAD_CLIENT &&
remainingBytes >= packet->header.payloadSize) {
for (u32 j = 0; j < packet->header.payloadSize; j++)
packet->payload[j] = buffer[cursor++];
remainingBytes -= packet->header.payloadSize;
}
clientResponse->packetsSize++;
}
}
return childrenData;
}
/**
* @brief Parses the `response` and returns a struct containing all the
* received packets from the host.
* @param response The response to be parsed.
*/
[[nodiscard]]
ParentData getParentData(LinkRawWireless::ReceiveDataResponse response) {
u8* buffer = (u8*)response.data;
u32 cursor = 0;
ParentData parentData;
if (response.sentBytes[0] > response.dataSize * 4)
return parentData;
ServerResponse* serverResponse = &parentData.response;
u32 remainingBytes = response.sentBytes[0];
while (remainingBytes >= HEADER_SIZE_SERVER) {
ServerPacket* packet =
&serverResponse->packets[serverResponse->packetsSize];
u32 headerInt = (*((u16*)(buffer + cursor))) |
(((*((u8*)(buffer + cursor + 2)))) << 16);
packet->header = parseServerHeader(headerInt);
cursor += HEADER_SIZE_SERVER;
remainingBytes -= HEADER_SIZE_SERVER;
if (packet->header.payloadSize > 0 &&
packet->header.payloadSize <= MAX_PAYLOAD_SERVER &&
remainingBytes >= packet->header.payloadSize) {
for (u32 j = 0; j < packet->header.payloadSize; j++)
packet->payload[j] = buffer[cursor++];
remainingBytes -= packet->header.payloadSize;
}
serverResponse->packetsSize++;
}
return parentData;
}
/**
* @brief Creates a buffer for the host to send a `fullPayload` with a valid
* header. If `fullPayloadSize` is higher than `84` (the maximum payload
* size), the buffer will only contain the **first** `84` bytes (unless an
* `offset` > 0 is used). A `sequence` number must be created by using
* `LinkWirelessOpenSDK::SequenceNumber::fromPacketId(...)`. Optionally, a
* `targetSlots` bit array can be used to exclude some clients from the
* transmissions (the default is `0b1111`).
* @param fullPayload A pointer to the payload buffer.
* @param fullPayloadSize Total size of the payload.
* @param sequence A sequence number created using
* `LinkWirelessOpenSDK::SequenceNumber::fromPacketId(...)`.
* @param targetSlots A bit array that can be used to exclude some clients
* (the default is `0b1111`).
* @param offset The offset within the `fullPayload` pointer. Defaults to `0`.
*/
[[nodiscard]]
SendBuffer<ServerSDKHeader> createServerBuffer(const u8* fullPayload,
u32 fullPayloadSize,
SequenceNumber sequence,
u8 targetSlots = 0b1111,
u32 offset = 0) {
SendBuffer<ServerSDKHeader> buffer;
u32 payloadSize = Link::_min(fullPayloadSize, MAX_PAYLOAD_SERVER);
buffer.header.isACK = 0;
buffer.header.targetSlots = targetSlots;
buffer.header.payloadSize = payloadSize;
buffer.header.n = sequence.n;
buffer.header.phase = sequence.phase;
buffer.header.commState = sequence.commState;
u32 headerInt = serializeServerHeader(buffer.header);
buffer.data[buffer.dataSize++] = headerInt;
if (offset < fullPayloadSize)
buffer.data[0] |= fullPayload[offset] << 24;
for (u32 i = 1; i < payloadSize; i += 4) {
u32 word = 0;
for (u32 j = 0; j < 4; j++) {
if (offset + i + j < fullPayloadSize && i + j < MAX_PAYLOAD_SERVER) {
u8 byte = fullPayload[offset + i + j];
word |= byte << (j * 8);
}
}
buffer.data[buffer.dataSize++] = word;
}
buffer.totalByteCount = HEADER_SIZE_SERVER + payloadSize;
return buffer;
}
/**
* @brief Creates a buffer for the host to acknowledge a header received from
* a certain `clientNumber`.
* @param clientHeader The header of the received packet.
* @param clientNumber `(0~3)` The client number that sent the packet.
*/
[[nodiscard]]
SendBuffer<ServerSDKHeader> createServerACKBuffer(
ClientSDKHeader clientHeader,
u8 clientNumber) {
SendBuffer<ServerSDKHeader> buffer;
buffer.header = createACKHeaderFor(clientHeader, clientNumber);
u32 headerInt = serializeServerHeader(buffer.header);
buffer.data[buffer.dataSize++] = headerInt;
buffer.totalByteCount = HEADER_SIZE_SERVER;
return buffer;
}
/**
* @brief Creates a buffer for the client to send a `fullPayload` with a valid
* header. If `fullPayloadSize` is higher than `14` (the maximum payload
* size), the buffer will only contain the **first** `14` bytes (unless an
* `offset` > 0 is used). A `sequence` number must be created by using
* `LinkWirelessOpenSDK::SequenceNumber::fromPacketId(...)`.
* @param fullPayload A pointer to the payload buffer.
* @param fullPayloadSize Total size of the payload.
* @param sequence A sequence number created using
* `LinkWirelessOpenSDK::SequenceNumber::fromPacketId(...)`.
* @param offset The offset within the `fullPayload` pointer. Defaults to `0`.
*/
[[nodiscard]]
SendBuffer<ClientSDKHeader> createClientBuffer(const u8* fullPayload,
u32 fullPayloadSize,
SequenceNumber sequence,
u32 offset = 0) {
SendBuffer<ClientSDKHeader> buffer;
u32 payloadSize = Link::_min(fullPayloadSize, MAX_PAYLOAD_CLIENT);
buffer.header.isACK = 0;
buffer.header.payloadSize = payloadSize;
buffer.header.n = sequence.n;
buffer.header.phase = sequence.phase;
buffer.header.commState = sequence.commState;
u16 headerInt = serializeClientHeader(buffer.header);
buffer.data[buffer.dataSize++] = headerInt;
if (offset < fullPayloadSize)
buffer.data[0] |= fullPayload[offset] << 16;
if (offset + 1 < fullPayloadSize)
buffer.data[0] |= fullPayload[offset + 1] << 24;
for (u32 i = 2; i < payloadSize; i += 4) {
u32 word = 0;
for (u32 j = 0; j < 4; j++) {
if (offset + i + j < fullPayloadSize && i + j < MAX_PAYLOAD_CLIENT) {
u8 byte = fullPayload[offset + i + j];
word |= byte << (j * 8);
}
}
buffer.data[buffer.dataSize++] = word;
}
buffer.totalByteCount = HEADER_SIZE_CLIENT + payloadSize;
return buffer;
}
/**
* @brief Creates a buffer for the client to acknowledge a header received
* from the host.
* @param serverHeader The header of the received packet.
*/
[[nodiscard]]
SendBuffer<ClientSDKHeader> createClientACKBuffer(
ServerSDKHeader serverHeader) {
SendBuffer<ClientSDKHeader> buffer;
buffer.header = createACKHeaderFor(serverHeader);
u16 headerInt = serializeClientHeader(buffer.header);
buffer.data[buffer.dataSize++] = headerInt;
buffer.totalByteCount = HEADER_SIZE_CLIENT;
return buffer;
}
private:
[[nodiscard]]
ServerSDKHeader createACKHeaderFor(ClientSDKHeader clientHeader,
u8 clientNumber) {
ServerSDKHeader serverHeader;
serverHeader.isACK = 1;
serverHeader.targetSlots = (1 << clientNumber);
serverHeader.payloadSize = 0;
serverHeader.n = clientHeader.n;
serverHeader.phase = clientHeader.phase;
serverHeader.commState = clientHeader.commState;
return serverHeader;
}
[[nodiscard]]
ClientSDKHeader createACKHeaderFor(ServerSDKHeader serverHeader) {
ClientSDKHeader clientHeader;
clientHeader.isACK = 1;
clientHeader.payloadSize = 0;
clientHeader.n = serverHeader.n;
clientHeader.phase = serverHeader.phase;
clientHeader.commState = serverHeader.commState;
return clientHeader;
}
[[nodiscard]]
ClientSDKHeader parseClientHeader(u32 clientHeaderInt) {
ClientSDKHeaderSerializer clientSerializer;
clientSerializer.asInt = clientHeaderInt & HEADER_MASK_CLIENT;
return clientSerializer.asStruct;
}
[[nodiscard]]
u16 serializeClientHeader(ClientSDKHeader clientHeader) {
ClientSDKHeaderSerializer clientSerializer;
clientSerializer.asStruct = clientHeader;
return clientSerializer.asInt & HEADER_MASK_CLIENT;
}
[[nodiscard]]
ServerSDKHeader parseServerHeader(u32 serverHeaderInt) {
ServerSDKHeaderSerializer serverSerializer;
serverSerializer.asInt = serverHeaderInt & HEADER_MASK_SERVER;
return serverSerializer.asStruct;
}
[[nodiscard]]
u32 serializeServerHeader(ServerSDKHeader serverHeader) {
ServerSDKHeaderSerializer serverSerializer;
serverSerializer.asStruct = serverHeader;
return serverSerializer.asInt & HEADER_MASK_SERVER;
}
};
#endif // LINK_WIRELESS_OPEN_SDK_H