server.c

   1 /* depend: */
   2 /* cflags: */
   3 /* linker: color.o debug.o */
   4
   5 #include <assert.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #ifdef _WIN32 /* Windows */
  10 #include <winsock2.h>
  11 #include <ws2tcpip.h>
  12 #else /* Posix */
  13 #include <errno.h>
  14 #include <unistd.h>
  15 #include <fcntl.h>
  16 #include <netinet/ip.h>
  17 #include <netinet/tcp.h>
  18 //#include <sys/types.h>
  19 //#include <sys/socket.h>
  20 #include <sys/select.h>
  21 #endif
  22
  23 #include "debug.h"
  24
  25 #include "server.h"
  26
  27 /* compat */
  28
  29 #ifdef _WIN32 /* Windows */
  30 #define PF_INET AF_INET
  31 #define ERRNO (WSAGetLastError ())
  32 #else /* Posix */
  33 #define closesocket close
  34 #define ERRNO errno
  35 #define SOCKET_ERROR -1
  36 #endif
  37
  38 /* types */
  39
  40 /* constants */
  41
  42 #define BACKLOG 5
  43 #define BUFFER_SIZE 4096
  44 #define TIMEOUT 100000
  45
  46 /* macros */
  47
  48 /* gobal variables */
  49
  50 /* init network context */
  51
  52 void init_network_context (void)
  53 {
  54 #ifdef _WIN32 /* Windows */
  55     WSADATA WSAData;
  56     WSAStartup (MAKEWORD(2,0), &WSAData);
  57     assert (INVALID_SOCKET == (socket_t)-1);
  58     assert (SOCKET_ERROR == -1);
  59 #endif
  60 }
  61
  62 /* terminate network context */
  63
  64 void terminate_network_context (void)
  65 {
  66 #ifdef _WIN32 /* Windows */
  67     WSACleanup ();
  68 #endif
  69 }
  70
  71 /* open listening socket */
  72
  73 socket_t open_listening_socket (int port)
  74 {
  75     int val = 1;
  76
  77     VERBOSE (DEBUG, fprintf (stdout, "Opening socket\n"));
  78     //socket_t sock = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);
  79     socket_t sock = socket (AF_INET, SOCK_STREAM, 0);
  80     if (sock == INVALID_SOCKET) {
  81         return -1;
  82     }
  83
  84     struct sockaddr_in addr = {0};
  85     bzero (&addr, sizeof (addr));
  86     //addr.sin_family = PF_INET;
  87     addr.sin_family = AF_INET;
  88     addr.sin_port = htons (port);
  89     addr.sin_addr.s_addr = htonl (INADDR_ANY);
  90
  91     VERBOSE (DEBUG, fprintf (stdout, "Binding socket\n"));
  92     //setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof (val));
  93     int rc = bind (sock, (struct sockaddr *)&addr, sizeof (addr));
  94     if (rc == SOCKET_ERROR) {
  95         VERBOSE (ERROR, fprintf (stderr, "error: bind %d\n", ERRNO));
  96         rc = closesocket (sock);
  97         if (rc == SOCKET_ERROR) {
  98             VERBOSE (ERROR, fprintf (stderr, "error: close %d\n", ERRNO));
  99         }
 100         return -1;
 101     }
 102
 103     VERBOSE (DEBUG, fprintf (stdout, "Configuring socket\n"));
 104 #ifndef _WIN32 /* Posix */
 105     fcntl (sock, F_SETFL, O_NONBLOCK);
 106 #endif
 107     rc = setsockopt (sock, IPPROTO_TCP, TCP_NODELAY, (char *)&val, sizeof (val));
 108     if (rc < 0) {
 109         VERBOSE (ERROR, fprintf (stderr, "error: %s\n", "setsockopt/TCP_NODELAY"));
 110         closesocket (sock);
 111         if (rc == SOCKET_ERROR) {
 112             VERBOSE (ERROR, fprintf (stderr, "error: close %d\n", ERRNO));
 113         }
 114         return -1;
 115     }
 116
 117     rc = listen (sock, BACKLOG);
 118     if (rc < 0) {
 119         VERBOSE (ERROR, fprintf (stderr, "error: %s\n", "listen"));
 120         closesocket (sock);
 121         if (rc == SOCKET_ERROR) {
 122             VERBOSE (ERROR, fprintf (stderr, "error: close %d\n", ERRNO));
 123         }
 124         return -1;
 125     }
 126
 127     return sock;
 128 }
 129
 130 /* accept incomming connection */
 131
 132 socket_t accept_incoming_connection (socket_t sock)
 133 {
 134     socket_t connection = accept (sock, NULL, 0);
 135     if (connection < 0) {
 136         return INVALID_SOCKET;
 137     }
 138
 139 #ifndef _WIN32 /* POSIX */
 140     fcntl (connection, F_SETFL, O_NONBLOCK);
 141 #endif
 142     int val = 1;
 143     int rc = setsockopt (connection, IPPROTO_TCP, TCP_NODELAY, (char *)&val, sizeof (val));
 144     if (rc < 0) {
 145         VERBOSE (ERROR, fprintf (stderr, "error: %s\n", "setsockopt/TCP_NODELAY"));
 146         closesocket (connection);
 147         if (rc == SOCKET_ERROR) {
 148             VERBOSE (ERROR, fprintf (stderr, "error: close %d\n", ERRNO));
 149         }
 150         return INVALID_SOCKET;
 151     }
 152
 153     return connection;
 154 }
 155
 156 /* close listening socket */
 157
 158 void close_socket (socket_t sock)
 159 {
 160     int rc = closesocket (sock);
 161     if (rc == SOCKET_ERROR) {
 162         VERBOSE (ERROR, fprintf (stderr, "error: %d\n", ERRNO));
 163     }
 164 }
 165
 166 /* receive data from socket */
 167
 168 int receive_data (socket_t sock, unsigned char **pdata)
 169 {
 170     unsigned char buffer[BUFFER_SIZE] = {0};
 171     unsigned char *data = NULL;
 172     int len = 0;
 173
 174     while (1) {
 175
 176         /* timeout management */
 177         fd_set rfds;
 178         struct timeval tv = { 0, TIMEOUT };
 179         FD_ZERO (&rfds);
 180         FD_SET (sock, &rfds);
 181
 182         int retval = select (sock + 1, &rfds, NULL, NULL, &tv);
 183         if (retval != 1) { /* 0 or SOCKET_ERROR */
 184             break;
 185         }
 186
 187         /* read from socket */
 188         int rc = read (sock, buffer, BUFFER_SIZE);
 189
 190         if (rc == 0) { /* sock closed */
 191             if (data) {
 192                 free (data);
 193                 data = NULL;
 194                 len  = 0;
 195             }
 196             break;
 197
 198         } else if ((rc < 0) && (ERRNO != EAGAIN)) { /* error */
 199             if (data) {
 200                 free (data);
 201                 data = NULL;
 202             }
 203             len  = -1;
 204             break;
 205
 206         } else if (rc > 0) {
 207             data = realloc (data, len + rc);
 208             memcpy (data + len, buffer, rc);
 209             len += rc;
 210         }
 211     }
 212
 213     if (pdata != NULL) {
 214         *pdata = data;
 215     }
 216     return len;
 217 }
 218
 219 /* send data onto socket */
 220
 221 int send_data (socket_t sock, unsigned char *data, int len)
 222 {
 223     int index = 0;
 224
 225     while (index < len) {
 226         int rc = write (sock, data + index, len - index);
 227
 228         if (rc == 0) { /* sock closed */
 229             index = 0;
 230             break;
 231         } else if ((rc < 0) && (ERRNO != EAGAIN)) { /* error */
 232             index = -1;
 233             break;
 234         } else if (rc > 0) {
 235             index += rc;
 236         }
 237     }
 238
 239     return index;
 240 }
 241
 242 /* vim: set ts=4 sw=4 et: */