WDP (Water Drop Protocol)

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Description

WDP is a lightweight TCP data transfer protocol designed to: Ensure data boundaries for complete packet reception (Yeah, only this!)

Platform Support

WDP supports both Windows and Linux platforms.

Quick Start

Maximum Data Size

For security reasons, WDP will limit the maximum data size that can be received. WDP allows configuring the maximum data size at runtime (default is 1MB):

// Get current maximum data size
unsigned int current = wdpGetMaxDataSize();
// Change maximum size to 2MB
wdpSetMaxDataSize(2 * 1024 * 1024);

Initialization and Cleanup

#include "wdp.h"
// wdpInit will initialize WSADATA on Windows. It is not necessary on Linux.
if (wdpInit() != 0) {
    // Handle initialization error
}

// Free WSADATA on Windows.
wdpCleanup();

Sending Data

// Send data using WDP Protocol
byte dataToSend[] = "Hello, WDP!";
WDP packet = wdpPack(dataToSend, sizeof(dataToSend));
int bytesSent = wdpSend(socket, packet);
if (bytesSent < 0) {
    // Handle send error
}
wdpFree(&packet); // Free allocated memory
// ...
wdpCleanup();

Receiving Data

// Receive data using WDP Protocol
WDP receivedPacket;
int result = wdpRecv(socket, &receivedPacket, 5000); // 5 seconds timeout
if (result < 0) {
    // Handle receive error
}
// Process received data
receivedPacket.data; // Pointer to data
receivedPacket.dataLen; // Length of data

wdpFree(&receivedPacket); // Free allocated memory
// ...
wdpCleanup();

Easy Error Handling

WDP provides easy-to-use error handling functions:

int errCode = wdpSend(socket, packet);
if (errCode < 0) {
    const char* errMsg = wdpGetErrorString(errCode);
    printf("WDP Error: %s\n", errMsg);
}

// ====================================================

// Handle error codes
switch (errCode) {
    case WDP_ERR_NETWORK_TIMEOUT:
        // Handle timeout
        break;
    case WDP_ERR_MEMORY_ALLOC_FAILED:
        // Handle memory allocation failure
        break;
    // Add more cases as needed
    default:
        // Handle unknown error
        break;
}

/*
You can refer to the error codes defined(in wdp.h):

// Success
    WDP_SUCCESS = 0,

    // Network-related errors (-100 ~ -199)
    WDP_ERR_NETWORK_SEND_FAILED = -100,      // send() failed
    WDP_ERR_NETWORK_RECV_FAILED = -101,      // recv() failed
    WDP_ERR_NETWORK_TIMEOUT = -102,          // Receive timeout
    WDP_ERR_NETWORK_PEER_CLOSED = -103,      // Peer closed connection
    WDP_ERR_NETWORK_INCOMPLETE = -104,       // Incomplete receive

    // Socket-related errors (-200 ~ -299)
    WDP_ERR_SOCKET_INVALID = -200,           // Invalid socket
    WDP_ERR_SOCKET_NOT_CONNECTED = -201,     // Socket not connected
    WDP_ERR_SOCKET_SELECT_FAILED = -202,     // select() failed

    // Memory-related errors (-300 ~ -399)
    WDP_ERR_MEMORY_ALLOC_FAILED = -300,      // Memory allocation failed
    WDP_ERR_MEMORY_COPY_FAILED = -301,       // memcpy failed
    WDP_ERR_MEMORY_NULL_POINTER = -302,      // Null pointer

    // Protocol-related errors (-400 ~ -499)
    WDP_ERR_PROTOCOL_VERSION_MISMATCH = -400, // Version mismatch
    WDP_ERR_PROTOCOL_INVALID_LENGTH = -401,   // Invalid data length
    WDP_ERR_PROTOCOL_DATA_TOO_LARGE = -402,   // Data exceeds maximum limit
    WDP_ERR_PROTOCOL_HEADER_INCOMPLETE = -403, // Header incomplete

    // Parameter-related errors (-500 ~ -599)
    WDP_ERR_PARAM_INVALID = -500,            // Invalid parameter
    WDP_ERR_PARAM_NULL_DATA = -501,          // Null data pointer
    WDP_ERR_PARAM_BUFFER_TOO_SMALL = -502,   // Buffer too small
*/