lua/luasocket.c

   1 /* Copyright (C) Chris Porter 2007 */
   2
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <sys/poll.h>
   6 #include <netinet/in.h>
   7 #include <sys/socket.h>
   8 #include <sys/un.h>
   9 #include <errno.h>
  10 #include <fcntl.h>
  11 #include "../lib/strlfunc.h"
  12 #include "../core/events.h"
  13
  14 #include "lua.h"
  15 #include "luabot.h"
  16
  17 #define lua_vnpcall(F2, N2, S2, ...) _lua_vpcall(F2->l->l, (void *)F2->handler, LUA_POINTERMODE, "lsR" S2 , F2->identifier, N2, F2->tag , ##__VA_ARGS__)
  18
  19 /*
  20  * instead of these identifiers I could just use the file descriptor...
  21  * BUT I can't remember the exact semantics of the fd table WRT reuse...
  22  */
  23 static long nextidentifier = 0;
  24 static void lua_socket_poll_event(int fd, short events);
  25
  26 static int lua_socket_unix_connect(lua_State *l) {
  27   int len, ret;
  28   struct sockaddr_un r;
  29   char *path;
  30   lua_socket *ls;
  31   lua_list *ll;
  32
  33   ll = lua_listfromstate(l);
  34   if(!ll)
  35     return 0;
  36
  37   if(!lua_isfunction(l, 2))
  38     return 0;
  39
  40   path = (char *)lua_tostring(l, 1);
  41   if(!path)
  42     return 0;
  43
  44   ls = (lua_socket *)luamalloc(sizeof(lua_socket));
  45   if(!ls)
  46     return 0;
  47
  48   ls->fd = socket(AF_UNIX, SOCK_STREAM, 0);
  49   if(ls->fd <= -1) {
  50     luafree(ls);
  51     return 0;
  52   }
  53
  54   memset(&r, 0, sizeof(r));
  55   r.sun_family = AF_UNIX;
  56   strlcpy(r.sun_path, path, sizeof(r.sun_path));
  57
  58   /* don't really like this, there's a macro in sys/un.h but it's not there under FreeBSD */
  59   len = sizeof(r.sun_family) + strlen(r.sun_path) + 1;
  60
  61   /* WTB exceptions */
  62   ret = fcntl(ls->fd, F_GETFL, 0);
  63   if(ret < 0) {
  64     luafree(ls);
  65     close(ls->fd);
  66     return 0;
  67   }
  68
  69   ret = fcntl(ls->fd, F_SETFL, ret | O_NONBLOCK);
  70   if(ret < 0) {
  71     luafree(ls);
  72     close(ls->fd);
  73     return 0;
  74   }
  75
  76   ret = connect(ls->fd, (struct sockaddr *)&r, len);
  77   if(ret == 0) {
  78     ls->state = SOCKET_CONNECTED;
  79   } else if(ret == -1 && (errno == EINPROGRESS)) {
  80     ls->state = SOCKET_CONNECTING;
  81   } else {
  82     luafree(ls);
  83     close(ls->fd);
  84     return 0;
  85   }
  86
  87   /* this whole identifier thing should probably use userdata stuff */
  88   ls->identifier = nextidentifier++;
  89   ls->tag = luaL_ref(l, LUA_REGISTRYINDEX);
  90   ls->handler = luaL_ref(l, LUA_REGISTRYINDEX);
  91
  92   ls->l = ll;
  93
  94   ls->next = ll->sockets;
  95   ll->sockets = ls;
  96
  97   registerhandler(ls->fd, (ls->state==SOCKET_CONNECTED?POLLIN:POLLOUT) | POLLERR | POLLHUP, lua_socket_poll_event);
  98
  99   lua_pushboolean(l, ls->state==SOCKET_CONNECTED?1:0);
 100   lua_pushlong(l, ls->identifier);
 101   return 2;
 102 }
 103
 104 static lua_socket *socketbyfd(int fd) {
 105   lua_list *l;
 106   lua_socket *ls;
 107
 108   for(l=lua_head;l;l=l->next)
 109     for(ls=l->sockets;ls;ls=ls->next)
 110       if(ls->fd == fd)
 111         return ls;
 112
 113   return NULL;
 114 }
 115
 116 static lua_socket *socketbyidentifier(long identifier) {
 117   lua_list *l;
 118   lua_socket *ls;
 119
 120   for(l=lua_head;l;l=l->next)
 121     for(ls=l->sockets;ls;ls=ls->next)
 122       if(ls->identifier == identifier)
 123         return ls;
 124
 125   return NULL;
 126 }
 127
 128 static void lua_socket_call_close(lua_socket *ls) {
 129   lua_socket *p, *c;
 130
 131   for(c=ls->l->sockets,p=NULL;c;p=c,c=c->next) {
 132     if(c == ls) {
 133       if(ls->state == SOCKET_CLOSED)
 134         return;
 135
 136       ls->state = SOCKET_CLOSED;
 137       deregisterhandler(ls->fd, 1);
 138
 139       lua_vnpcall(ls, "close", "");
 140
 141       if(!p) {
 142         ls->l->sockets = ls->next;
 143       } else {
 144         p->next = ls->next;
 145       }
 146
 147       luaL_unref(ls->l->l, LUA_REGISTRYINDEX, ls->tag);
 148       luaL_unref(ls->l->l, LUA_REGISTRYINDEX, ls->handler);
 149
 150       luafree(ls);
 151       return;
 152     }
 153   }
 154
 155 }
 156
 157 static int lua_socket_write(lua_State *l) {
 158   char *buf;
 159   long len;
 160   lua_socket *ls;
 161   int ret;
 162
 163   buf = (char *)lua_tostring(l, 2);
 164
 165   if(!lua_islong(l, 1) || !buf) {
 166     lua_pushint(l, -1);
 167     return 1;
 168   }
 169   len = lua_strlen(l, 2);
 170
 171   ls = socketbyidentifier(lua_tolong(l, 1));
 172   if(!ls || (ls->state != SOCKET_CONNECTED)) {
 173     lua_pushint(l, -1);
 174     return 1;
 175   }
 176
 177   ret = write(ls->fd, buf, len);
 178   if(ret == -1 && (errno == EAGAIN)) {
 179     deregisterhandler(ls->fd, 0);
 180     registerhandler(ls->fd, POLLIN | POLLOUT | POLLERR | POLLHUP, lua_socket_poll_event);
 181
 182     lua_pushint(l, 0);
 183     return 1;
 184   }
 185
 186   if(ret == -1)
 187     lua_socket_call_close(ls);
 188
 189   if(ret < len) {
 190     deregisterhandler(ls->fd, 0);
 191     registerhandler(ls->fd, POLLIN | POLLOUT | POLLERR | POLLHUP, lua_socket_poll_event);
 192   }
 193
 194   lua_pushint(l, ret);
 195   return 1;
 196 }
 197
 198 static int lua_socket_close(lua_State *l) {
 199   lua_socket *ls;
 200
 201   if(!lua_islong(l, 1))
 202     LUA_RETURN(l, LUA_FAIL);
 203
 204   ls = socketbyidentifier(lua_tolong(l, 1));
 205   if(!ls || (ls->state == SOCKET_CLOSED))
 206     LUA_RETURN(l, LUA_FAIL);
 207
 208   lua_socket_call_close(ls);
 209
 210   LUA_RETURN(l, LUA_OK);
 211 }
 212
 213 static void lua_socket_poll_event(int fd, short events) {
 214   lua_socket *ls = socketbyfd(fd);
 215   if(!ls || (ls->state == SOCKET_CLOSED))
 216     return;
 217
 218   if(events & (POLLERR | POLLHUP)) {
 219     lua_socket_call_close(ls);
 220     return;
 221   }
 222
 223   switch(ls->state) {
 224     case SOCKET_CONNECTING:
 225       if(events & POLLOUT) {
 226         deregisterhandler(fd, 0);
 227         registerhandler(fd, POLLIN | POLLERR | POLLHUP, lua_socket_poll_event);
 228         ls->state = SOCKET_CONNECTED;
 229
 230         lua_vnpcall(ls, "connect", "");
 231       }
 232       break;
 233     case SOCKET_CONNECTED:
 234       if(events & POLLOUT) {
 235         deregisterhandler(fd, 0);
 236         registerhandler(fd, POLLIN | POLLERR | POLLHUP, lua_socket_poll_event);
 237
 238         lua_vnpcall(ls, "flush", "");
 239       }
 240       if(events & POLLIN) {
 241         char buf[8192 * 2];
 242         int bytesread;
 243
 244         bytesread = read(fd, buf, sizeof(buf));
 245         if((bytesread == -1) && (errno == EAGAIN))
 246           return;
 247
 248         if(bytesread <= 0) {
 249           lua_socket_call_close(ls);
 250          return;
 251         }
 252
 253         lua_vnpcall(ls, "read", "L", buf, (long)bytesread);
 254       }
 255       break;
 256   }
 257 }
 258
 259 void lua_socket_closeall(lua_list *l) {
 260   while(l->sockets)
 261     lua_socket_call_close(l->sockets);
 262 }
 263
 264 void lua_registersocketcommands(lua_State *l) {
 265   lua_register(l, "socket_unix_connect", lua_socket_unix_connect);
 266   lua_register(l, "socket_close", lua_socket_close);
 267   lua_register(l, "socket_write", lua_socket_write);
 268 }