echo server

[webserver.git] / server.c

/* depend: */
/* cflags: */
/* linker: color.o debug.o */

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef _WIN32 /* Windows */
#include <winsock2.h>
#include <ws2tcpip.h>
#else /* Posix */
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
//#include <sys/types.h>
//#include <sys/socket.h>
#include <sys/select.h>
#endif
#include <unistd.h>

#include "debug.h"

#include "server.h"

/* compat */

#ifdef _WIN32 /* Windows */
#define PF_INET AF_INET
#define ERRNO (WSAGetLastError ())
#else /* Posix */
#define closesocket close
#define ERRNO errno
#define SOCKET_ERROR -1
#endif

/* types */

/* constants */

#define BACKLOG 5
#define BUFFER_SIZE 4096
#define TIMEOUT 100000

/* macros */

/* gobal variables */

/* init network context */

void init_network_context (void)
{
#ifdef _WIN32 /* Windows */
    WSADATA WSAData;
    WSAStartup (MAKEWORD(2,0), &WSAData);
    assert (INVALID_SOCKET == (socket_t)-1);
    assert (SOCKET_ERROR == -1);
#endif
}

/* terminate network context */

void terminate_network_context (void)
{
#ifdef _WIN32 /* Windows */
    WSACleanup ();
#endif
}

/* open listening socket */

socket_t open_listening_socket (int port)
{
    int val = 1;

    VERBOSE (DEBUG, PRINT ("Opening socket\n"));
    //socket_t sock = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);
    socket_t sock = socket (AF_INET, SOCK_STREAM, 0);
    if (sock == INVALID_SOCKET) {
        return -1;
    }

    struct sockaddr_in addr = {0};
    //bzero (&addr, sizeof (addr));
    //addr.sin_family = PF_INET;
    addr.sin_family = AF_INET;
    addr.sin_port = htons (port);
    addr.sin_addr.s_addr = htonl (INADDR_ANY);

    VERBOSE (DEBUG, PRINT ("Binding socket\n"));
    //setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof (val));
    int rc = bind (sock, (struct sockaddr *)&addr, sizeof (addr));
    if (rc == SOCKET_ERROR) {
        VERBOSE (ERROR, PERROR ("error: bind %d\n", ERRNO));
        rc = closesocket (sock);
        if (rc == SOCKET_ERROR) {
            VERBOSE (ERROR, PERROR ("error: close %d\n", ERRNO));
        }
        return -1;
    }

    VERBOSE (DEBUG, PRINT ("Configuring socket\n"));
#ifndef _WIN32 /* Posix */
    fcntl (sock, F_SETFL, O_NONBLOCK);
#endif
    rc = setsockopt (sock, IPPROTO_TCP, TCP_NODELAY, (char *)&val, sizeof (val));
    if (rc < 0) {
        VERBOSE (ERROR, PERROR ("error: %s\n", "setsockopt/TCP_NODELAY"));
        closesocket (sock);
        if (rc == SOCKET_ERROR) {
            VERBOSE (ERROR, PERROR ("error: close %d\n", ERRNO));
        }
        return -1;
    }

    rc = listen (sock, BACKLOG);
    if (rc < 0) {
        VERBOSE (ERROR, PERROR ("error: %s\n", "listen"));
        closesocket (sock);
        if (rc == SOCKET_ERROR) {
            VERBOSE (ERROR, PERROR ("error: close %d\n", ERRNO));
        }
        return -1;
    }

    return sock;
}

/* accept incomming connection */

socket_t accept_incoming_connection (socket_t sock)
{
    socket_t connection = accept (sock, NULL, 0);
    if (connection == INVALID_SOCKET) {
        return INVALID_SOCKET;
    }

#ifndef _WIN32 /* POSIX */
    fcntl (connection, F_SETFL, O_NONBLOCK);
#endif
    int val = 1;
    int rc = setsockopt (connection, IPPROTO_TCP, TCP_NODELAY, (char *)&val, sizeof (val));
    if (rc < 0) {
        VERBOSE (ERROR, PERROR ("error: %s\n", "setsockopt/TCP_NODELAY"));
        closesocket (connection);
        if (rc == SOCKET_ERROR) {
            VERBOSE (ERROR, PERROR ("error: close %d\n", ERRNO));
        }
        return INVALID_SOCKET;
    }

    return connection;
}

/* close listening socket */

void close_socket (socket_t sock)
{
    int rc = closesocket (sock);
    if (rc == SOCKET_ERROR) {
        VERBOSE (ERROR, PERROR ("error: %d\n", ERRNO));
    }
}

/* receive data from socket */

int receive_data (socket_t sock, unsigned char **pdata)
{
    unsigned char buffer[BUFFER_SIZE] = {0};
    unsigned char *data = NULL;
    int len = 0;

    while (1) {

        /* timeout management */
        fd_set rfds;
        struct timeval tv = { 0, TIMEOUT };
        FD_ZERO (&rfds);
        FD_SET (sock, &rfds);

        int retval = select (sock + 1, &rfds, NULL, NULL, &tv);
        if (retval != 1) { /* 0 or SOCKET_ERROR */
            break;
        }

        /* read from socket */
        int rc = read (sock, buffer, BUFFER_SIZE);

        if (rc == 0) { /* sock closed */
            if (data) {
                free (data);
                data = NULL;
                len  = 0;
            }
            break;

        } else if ((rc < 0) && (ERRNO != EAGAIN)) { /* error */
            if (data) {
                free (data);
                data = NULL;
            }
            len  = -1;
            break;

        } else if (rc > 0) {
            data = realloc (data, len + rc);
            memcpy (data + len, buffer, rc);
            len += rc;
        }
    }

    if (pdata != NULL) {
        *pdata = data;
    }
    return len;
}

/* send data onto socket */

int send_data (socket_t sock, unsigned char *data, int len)
{
    int index = 0;

    while (index < len) {
        int rc = write (sock, data + index, len - index);

        if (rc == 0) { /* sock closed */
            index = 0;
            break;
        } else if ((rc < 0) && (ERRNO != EAGAIN)) { /* error */
            index = -1;
            break;
        } else if (rc > 0) {
            index += rc;
        }
    }

    return index;
}

/* vim: set ts=4 sw=4 et: */