server.c

   1 /*
   2  * Copyright 2004-2005 Timo Hirvonen
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  17  * 02111-1307, USA.
  18  */
  19
  20 #include <server.h>
  21 #include <prog.h>
  22 #include <command_mode.h>
  23 #include <debug.h>
  24 #include <config.h>
  25
  26 #include <unistd.h>
  27 #include <sys/un.h>
  28 #include <sys/types.h>
  29 #include <sys/socket.h>
  30 #include <errno.h>
  31 #include <stdio.h>
  32
  33 static struct sockaddr_un addr;
  34 static int remote_socket = -1;
  35
  36 #define MAX_CLIENTS 10
  37
  38 static void read_commands(int fd)
  39 {
  40         char buf[1024];
  41         int pos = 0;
  42
  43         while (1) {
  44                 int rc, s;
  45
  46                 rc = read(fd, buf + pos, sizeof(buf) - pos);
  47                 if (rc == -1) {
  48                         break;
  49                 }
  50                 if (rc == 0) {
  51                         break;
  52                 }
  53                 pos += rc;
  54
  55                 s = 0;
  56                 while (1) {
  57                         int i;
  58
  59                         for (i = s; i < pos; i++) {
  60                                 if (buf[i] == '\n') {
  61                                         buf[i] = 0;
  62                                         run_command(buf + s);
  63                                         s = i + 1;
  64                                         break;
  65                                 }
  66                         }
  67                         if (i == pos)
  68                                 break;
  69                 }
  70                 memmove(buf, buf + s, pos - s);
  71                 pos -= s;
  72         }
  73 }
  74
  75 int remote_server_serve(void)
  76 {
  77         struct sockaddr saddr;
  78         socklen_t saddr_size = sizeof(saddr);
  79         int fd;
  80
  81         fd = accept(remote_socket, &saddr, &saddr_size);
  82         if (fd == -1) {
  83                 return -1;
  84         }
  85         read_commands(fd);
  86         close(fd);
  87         return 0;
  88 }
  89
  90 int remote_server_init(const char *address)
  91 {
  92         /* create socket - domain, type, protocol (IP) */
  93         remote_socket = socket(PF_UNIX, SOCK_STREAM, 0);
  94         if (remote_socket == -1)
  95                 die_errno("socket");
  96         addr.sun_family = AF_UNIX;
  97         strncpy(addr.sun_path, address, sizeof(addr.sun_path) - 1);
  98
  99         if (bind(remote_socket, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
 100                 int sock;
 101
 102                 if (errno != EADDRINUSE)
 103                         die_errno("bind");
 104
 105                 /* address already in use */
 106
 107                 /* try to connect to server */
 108                 sock = socket(PF_UNIX, SOCK_STREAM, 0);
 109                 if (sock == -1)
 110                         die_errno("socket");
 111
 112                 if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
 113                         if (errno != ENOENT && errno != ECONNREFUSED)
 114                                 die_errno("connect");
 115
 116                         close(sock);
 117                         /* server not running => dead socket */
 118
 119                         /* try to remove dead socket */
 120                         if (unlink(addr.sun_path) == -1 && errno != ENOENT)
 121                                 die_errno("unlink");
 122                         if (bind(remote_socket, (struct sockaddr *)&addr, sizeof(addr)) == -1)
 123                                 die_errno("bind");
 124                 } else {
 125                         /* server already running */
 126                         close(sock);
 127                         die(PACKAGE " is already listening on socket %s\n", address);
 128                 }
 129         }
 130         /* start listening */
 131         BUG_ON(listen(remote_socket, MAX_CLIENTS) == -1);
 132         return remote_socket;
 133 }
 134
 135 void remote_server_exit(void)
 136 {
 137         close(remote_socket);
 138         if (unlink(addr.sun_path) == -1)
 139                 d_print("unlink failed\n");
 140 }