utun2/lib/socket_compat.c

/**
 * Socket compatibility layer implementation
 */

#include "socket_compat.h"
#include "debug_config.h"

#ifdef _WIN32
// ==================== Windows Implementation ====================

static int wsa_init_count = 0;

int socket_platform_init(void) {
    if (wsa_init_count == 0) {
        WSADATA wsaData;
        int result = WSAStartup(MAKEWORD(2, 2), &wsaData);
        if (result != 0) {
            DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, "WSAStartup failed: %d", result);
            return -1;
        }
        DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "Winsock 2.2 initialized");
    }
    wsa_init_count++;
    DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "Winsock init count: %d", wsa_init_count);
    return 0;
}

void socket_platform_cleanup(void) {
    if (wsa_init_count > 0) {
        wsa_init_count--;
        if (wsa_init_count == 0) {
            WSACleanup();
            DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "Winsock cleanup completed");
        } else {
            DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "Winsock init count after cleanup: %d", wsa_init_count);
        }
    }
}

int socket_set_nonblocking(socket_t sock) {
    u_long mode = 1;
    if (ioctlsocket(sock, FIONBIO, &mode) != 0) {
        DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, 
                   "ioctlsocket(FIONBIO) failed: %d", socket_get_error());
        return -1;
    }
    return 0;
}

int socket_close_wrapper(socket_t sock) {
    return closesocket(sock);
}

const char* socket_strerror(int err) {
    static char buf[256];
    FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
                   NULL, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                   buf, sizeof(buf), NULL);
    return buf;
}

#else
// ==================== POSIX Implementation ====================

int socket_platform_init(void) {
    // No initialization needed on POSIX
    DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "POSIX socket subsystem ready");
    return 0;
}

void socket_platform_cleanup(void) {
    // No cleanup needed on POSIX
    DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "POSIX socket cleanup completed");
}

int socket_set_nonblocking(socket_t sock) {
    int flags = fcntl(sock, F_GETFL, 0);
    if (flags < 0) {
        DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, 
                   "fcntl(F_GETFL) failed: %s", strerror(errno));
        return -1;
    }
    if (fcntl(sock, F_SETFL, flags | O_NONBLOCK) < 0) {
        DEBUG_ERROR(DEBUG_CATEGORY_SOCKET,
                   "fcntl(F_SETFL) failed: %s", strerror(errno));
        return -1;
    }
    return 0;
}

int socket_close_wrapper(socket_t sock) {
    return close(sock);
}

const char* socket_strerror(int err) {
    return strerror(err);
}

#endif

// ==================== Universal Implementations ====================

socket_t socket_create_udp(int family) {
    socket_t sock = socket(family, SOCK_DGRAM, IPPROTO_UDP);
    if (sock == SOCKET_INVALID) {
        DEBUG_ERROR(DEBUG_CATEGORY_SOCKET,
                   "socket(SOCK_DGRAM) failed: %s", socket_strerror(socket_get_error()));
        return SOCKET_INVALID;
    }
    DEBUG_DEBUG(DEBUG_CATEGORY_SOCKET, "Created UDP socket: %ld", (long)sock);
    return sock;
}

int socket_set_buffers(socket_t sock, int sndbuf, int rcvbuf) {
    int err = 0;
    
#ifdef _WIN32
    // Windows uses char* for optval
    if (setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
                   (const char*)&sndbuf, sizeof(sndbuf)) != 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_SNDBUF failed: %s", socket_strerror(socket_get_error()));
        err = -1;
    }
    if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
                   (const char*)&rcvbuf, sizeof(rcvbuf)) != 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_RCVBUF failed: %s", socket_strerror(socket_get_error()));
        err = -1;
    }
#else
    if (setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf)) < 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_SNDBUF failed: %s", strerror(errno));
        err = -1;
    }
    if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf)) < 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_RCVBUF failed: %s", strerror(errno));
        err = -1;
    }
#endif
    
    return err;
}

int socket_set_reuseaddr(socket_t sock, int reuse) {
#ifdef _WIN32
    if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
                   (const char*)&reuse, sizeof(reuse)) != 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_REUSEADDR failed: %s", socket_strerror(socket_get_error()));
        return -1;
    }
#else
    if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_REUSEADDR failed: %s", strerror(errno));
        return -1;
    }
#endif
    return 0;
}

int socket_bind_to_device(socket_t sock, const char* ifname) {
#ifndef _WIN32
#ifdef SO_BINDTODEVICE
    if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)) < 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_BINDTODEVICE failed: %s", strerror(errno));
        return -1;
    }
    return 0;
#else
    (void)sock;
    (void)ifname;
    DEBUG_DEBUG(DEBUG_CATEGORY_SOCKET, "SO_BINDTODEVICE not available");
    return -1;
#endif
#else
    // Windows doesn't support SO_BINDTODEVICE
    (void)sock;
    (void)ifname;
    DEBUG_DEBUG(DEBUG_CATEGORY_SOCKET, "SO_BINDTODEVICE not available on Windows");
    return -1;
#endif
}

int socket_set_mark(socket_t sock, int mark) {
#ifndef _WIN32
#ifdef SO_MARK
    if (setsockopt(sock, SOL_SOCKET, SO_MARK, &mark, sizeof(mark)) < 0) {
        DEBUG_WARN(DEBUG_CATEGORY_SOCKET,
                  "SO_MARK failed: %s", strerror(errno));
        return -1;
    }
    return 0;
#else
    (void)sock;
    (void)mark;
    DEBUG_DEBUG(DEBUG_CATEGORY_SOCKET, "SO_MARK not available");
    return -1;
#endif
#else
    // Windows doesn't support SO_MARK
    (void)sock;
    (void)mark;
    DEBUG_DEBUG(DEBUG_CATEGORY_SOCKET, "SO_MARK not available on Windows");
    return -1;
#endif
}

ssize_t socket_sendto(socket_t sock, const void* buf, size_t len,
                      struct sockaddr* dest, socklen_t dest_len) {
#ifdef _WIN32
    return sendto(sock, (const char*)buf, (int)len, 0, dest, dest_len);
#else
    return sendto(sock, buf, len, 0, dest, dest_len);
#endif
}

ssize_t socket_recvfrom(socket_t sock, void* buf, size_t len,
                        struct sockaddr* src, socklen_t* src_len) {
#ifdef _WIN32
    int fromlen = src_len ? (int)*src_len : 0;
    ssize_t ret = recvfrom(sock, (char*)buf, (int)len, 0, src, src_len ? &fromlen : NULL);
    if (src_len) *src_len = (socklen_t)fromlen;
    return ret;
#else
    return recvfrom(sock, buf, len, 0, src, src_len);
#endif
}