apps/mserver/main.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2010  Tomas 'ZeXx86' Jedrzejek (zexx86@zexos.org)
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 #include <fcntl.h>
  21 #include <netdb.h>
  22 #include <stdio.h>
  23 #include <string.h>
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <arpa/inet.h>
  27 #include <sys/socket.h>
  28 #include <sys/select.h>
  29 #include <netinet/in.h>
  30
  31 int fd;
  32 fd_set myset;
  33 struct sockaddr_in sockname;
  34
  35 /* Client structure */
  36 typedef struct client_context {
  37         struct client_context *next, *prev;
  38
  39         int fd;
  40 } client_t;
  41
  42 client_t client_list;
  43
  44 int mserver_bind (int port)
  45 {
  46         if ((fd = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1) {
  47                 printf ("> cant create socket\n");
  48                 return -1;
  49         }
  50
  51         sockname.sin_family = AF_INET;
  52         sockname.sin_port = htons (port);
  53
  54         // Create listen socket
  55         if (bind (fd, (struct sockaddr *) &sockname, sizeof (sockname)) == -1) {
  56                 printf ("bind () - port is used\n");
  57                 return -1;
  58         }
  59
  60         // Create queue for accept
  61         if (listen (fd, 10) == -1) {
  62                 printf ("ERROR -> listen () == -1\n");
  63                 return -1;
  64         }
  65
  66         client_list.next = &client_list;
  67         client_list.prev = &client_list;
  68
  69         return 0;
  70 }
  71
  72 int mserver_newclient ()
  73 {
  74         int client;
  75         struct sockaddr_in clientInfo;
  76         socklen_t addrlen = sizeof (clientInfo);
  77
  78         if (FD_ISSET (fd, &myset)) {
  79                 printf ("> new client connected\n");
  80
  81                 client = accept (fd, (struct sockaddr *) &clientInfo, &addrlen);
  82
  83                 if (client > 0) {
  84                         // alloc and init context
  85                         client_t *ctx = (client_t *) malloc (sizeof (client_t));
  86
  87                         if (!ctx)
  88                                 return 0;
  89
  90                         ctx->fd = client;
  91
  92                         ctx->next = &client_list;
  93                         ctx->prev = client_list.prev;
  94                         ctx->prev->next = ctx;
  95                         ctx->next->prev = ctx;
  96
  97                         return 1;
  98                 }
  99         }
 100
 101         return 0;
 102 }
 103
 104 int mserver_sendtoall (client_t *me, char *buf, unsigned len)
 105 {
 106         if (!me)
 107                 return -1;
 108
 109         client_t *c;
 110         for (c = client_list.next; c != &client_list; c = c->next)
 111                 if (c != me)
 112                         send (c->fd, buf, len, 0);
 113
 114         return 0;
 115 }
 116
 117 int mserver_handle (client_t *c)
 118 {
 119         if (!FD_ISSET (c->fd, &myset))
 120                 return 0;
 121
 122         char str[80];
 123         int r = recv (c->fd, str, 79, 0);
 124
 125         if (r > 0) {
 126                 str[r] = '\0';
 127
 128                 printf ("data: %d: %s", c->fd, str);
 129                 mserver_sendtoall (c, str, r);
 130         } else {
 131                 printf ("client %d is disconnected\n", c->fd);
 132                 /* disconnect socket */
 133                 close (c->fd);
 134
 135                 /* delete client_t * struct from list */
 136                 c->next->prev = c->prev;
 137                 c->prev->next = c->next;
 138
 139                 free (c);
 140                 return -1;
 141         }
 142
 143         return 0;
 144 }
 145
 146 int mserver_loop ()
 147 {
 148         struct timeval tv;
 149
 150         FD_ZERO (&myset);
 151         FD_SET (fd, &myset);
 152
 153         client_t *c;
 154         for (c = client_list.next; c != &client_list; c = c->next)
 155                 FD_SET (c->fd, &myset);
 156
 157         tv.tv_sec = 1;
 158         tv.tv_usec = 0;
 159
 160         int ret = select (0, &myset, NULL, NULL, &tv);
 161
 162         if (ret == -1) {
 163                 printf ("select error\n");
 164                 return -1;
 165         } else if (ret == 0) {
 166                 printf ("select timeout\n");
 167                 return -1;
 168         }
 169
 170         /* check for incoming connections */
 171         if (mserver_newclient ())
 172                 return 0;
 173
 174         for (c = client_list.next; c != &client_list; c = c->next) {
 175                 if (mserver_handle (c) == -1)
 176                         break;
 177         }
 178
 179         return 0;
 180 }
 181
 182 int main (int argc, char **argv)
 183 {
 184         int ret = mserver_bind (1234);
 185
 186         if (ret == -1)
 187                 return -1;
 188
 189         for (;; schedule ())
 190                 mserver_loop ();
 191
 192         return 0;
 193 }