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 getunixsocket(char *path, struct sockaddr_un *r) {
  27   int fd = socket(AF_UNIX, SOCK_STREAM, 0);
  28   int ret;
  29
  30   if(fd <= -1)
  31     return -1;
  32
  33   memset(r, 0, sizeof(struct sockaddr_un));
  34   r->sun_family = AF_UNIX;
  35   strlcpy(r->sun_path, path, sizeof(r->sun_path));
  36
  37   /* WTB exceptions */
  38   ret = fcntl(fd, F_GETFL, 0);
  39   if(ret < 0) {
  40     close(fd);
  41     return -1;
  42   }
  43
  44   ret = fcntl(fd, F_SETFL, ret | O_NONBLOCK);
  45   if(ret < 0) {
  46     close(fd);
  47     return -1;
  48   }
  49
  50   return fd;
  51 }
  52
  53 static void registerluasocket(lua_list *ll, lua_socket *ls, int mask, int settag) {
  54   /* this whole identifier thing should probably use userdata stuff */
  55   ls->identifier = nextidentifier++;
  56
  57   if(settag) {
  58     ls->tag = luaL_ref(ll->l, LUA_REGISTRYINDEX);
  59     ls->handler = luaL_ref(ll->l, LUA_REGISTRYINDEX);
  60   }
  61   ls->l = ll;
  62
  63   ls->next = ll->sockets;
  64   ll->sockets = ls;
  65
  66   registerhandler(ls->fd, mask, lua_socket_poll_event);
  67 }
  68
  69 static int lua_socket_unix_connect(lua_State *l) {
  70   int ret;
  71   struct sockaddr_un r;
  72   char *path;
  73   lua_socket *ls;
  74   lua_list *ll;
  75
  76   ll = lua_listfromstate(l);
  77   if(!ll)
  78     return 0;
  79
  80   if(!lua_isfunction(l, 2))
  81     return 0;
  82
  83   path = (char *)lua_tostring(l, 1);
  84   if(!path)
  85     return 0;
  86
  87   ls = (lua_socket *)luamalloc(sizeof(lua_socket));
  88   if(!ls)
  89     return 0;
  90
  91   ls->fd = getunixsocket(path, &r);
  92   if(ls->fd < 0) {
  93     luafree(ls);
  94     return 0;
  95   }
  96
  97   ret = connect(ls->fd, (struct sockaddr *)&r, sizeof(r.sun_family) + strlen(r.sun_path));
  98   if(ret == 0) {
  99     ls->state = SOCKET_CONNECTED;
 100   } else if(ret == -1 && (errno == EINPROGRESS)) {
 101     ls->state = SOCKET_CONNECTING;
 102   } else {
 103     luafree(ls);
 104     close(ls->fd);
 105     return 0;
 106   }
 107
 108   ls->parent = NULL;
 109   registerluasocket(ll, ls, (ls->state==SOCKET_CONNECTED?POLLIN:POLLOUT) | POLLERR | POLLHUP, 1);
 110
 111   lua_pushboolean(l, ls->state==SOCKET_CONNECTED?1:0);
 112   lua_pushlong(l, ls->identifier);
 113   return 2;
 114 }
 115
 116 static int lua_socket_unix_bind(lua_State *l) {
 117   lua_list *ll;
 118   char *path;
 119   lua_socket *ls;
 120   struct sockaddr_un r;
 121
 122   ll = lua_listfromstate(l);
 123   if(!ll)
 124     return 0;
 125
 126   if(!lua_isfunction(l, 2))
 127     return 0;
 128
 129   path = (char *)lua_tostring(l, 1);
 130   if(!path)
 131     return 0;
 132
 133   ls = (lua_socket *)luamalloc(sizeof(lua_socket));
 134   if(!ls)
 135     return 0;
 136
 137   ls->fd = getunixsocket(path, &r);
 138   if(ls->fd <= -1) {
 139     luafree(ls);
 140     return 0;
 141   }
 142
 143   unlink(path);
 144
 145   if(
 146     (bind(ls->fd, (struct sockaddr *)&r, strlen(r.sun_path) + sizeof(r.sun_family)) == -1) ||
 147     (listen(ls->fd, 5) == -1)
 148   ) {
 149     close(ls->fd);
 150     luafree(ls);
 151     return 0;
 152   }
 153
 154   ls->state = SOCKET_LISTENING;
 155   ls->parent = NULL;
 156
 157   registerluasocket(ll, ls, POLLIN, 1);
 158
 159   lua_pushlong(l, ls->identifier);
 160   return 1;
 161 }
 162
 163 static lua_socket *socketbyfd(int fd) {
 164   lua_list *l;
 165   lua_socket *ls;
 166
 167   for(l=lua_head;l;l=l->next)
 168     for(ls=l->sockets;ls;ls=ls->next)
 169       if(ls->fd == fd)
 170         return ls;
 171
 172   return NULL;
 173 }
 174
 175 static lua_socket *socketbyidentifier(long identifier) {
 176   lua_list *l;
 177   lua_socket *ls;
 178
 179   for(l=lua_head;l;l=l->next)
 180     for(ls=l->sockets;ls;ls=ls->next)
 181       if(ls->identifier == identifier)
 182         return ls;
 183
 184   return NULL;
 185 }
 186
 187 static void lua_socket_call_close(lua_socket *ls) {
 188   lua_socket *p, *c;
 189
 190   for(c=ls->l->sockets;c;c=p) {
 191     p = c->next;
 192     if(c->parent == ls)
 193       lua_socket_call_close(c);
 194   }
 195
 196   for(c=ls->l->sockets,p=NULL;c;p=c,c=c->next) {
 197     if(c == ls) {
 198       if(ls->state == SOCKET_CLOSED)
 199         return;
 200
 201       ls->state = SOCKET_CLOSED;
 202       deregisterhandler(ls->fd, 1);
 203
 204       lua_vnpcall(ls, "close", "");
 205
 206       if(!p) {
 207         ls->l->sockets = ls->next;
 208       } else {
 209         p->next = ls->next;
 210       }
 211
 212       if(!ls->parent) {
 213         luaL_unref(ls->l->l, LUA_REGISTRYINDEX, ls->tag);
 214         luaL_unref(ls->l->l, LUA_REGISTRYINDEX, ls->handler);
 215       }
 216
 217       luafree(ls);
 218       return;
 219     }
 220   }
 221 }
 222
 223 static int lua_socket_write(lua_State *l) {
 224   char *buf;
 225   long len;
 226   lua_socket *ls;
 227   int ret;
 228
 229   buf = (char *)lua_tostring(l, 2);
 230
 231   if(!lua_islong(l, 1) || !buf) {
 232     lua_pushint(l, -1);
 233     return 1;
 234   }
 235   len = lua_strlen(l, 2);
 236
 237   ls = socketbyidentifier(lua_tolong(l, 1));
 238   if(!ls || (ls->state != SOCKET_CONNECTED)) {
 239     lua_pushint(l, -1);
 240     return 1;
 241   }
 242
 243   ret = write(ls->fd, buf, len);
 244   if(ret == -1 && (errno == EAGAIN)) {
 245     deregisterhandler(ls->fd, 0);
 246     registerhandler(ls->fd, POLLIN | POLLOUT | POLLERR | POLLHUP, lua_socket_poll_event);
 247
 248     lua_pushint(l, 0);
 249     return 1;
 250   }
 251
 252   if(ret == -1)
 253     lua_socket_call_close(ls);
 254
 255   if(ret < len) {
 256     deregisterhandler(ls->fd, 0);
 257     registerhandler(ls->fd, POLLIN | POLLOUT | POLLERR | POLLHUP, lua_socket_poll_event);
 258   }
 259
 260   lua_pushint(l, ret);
 261   return 1;
 262 }
 263
 264 static int lua_socket_close(lua_State *l) {
 265   lua_socket *ls;
 266
 267   if(!lua_islong(l, 1))
 268     LUA_RETURN(l, LUA_FAIL);
 269
 270   ls = socketbyidentifier(lua_tolong(l, 1));
 271   if(!ls || (ls->state == SOCKET_CLOSED))
 272     LUA_RETURN(l, LUA_FAIL);
 273
 274   lua_socket_call_close(ls);
 275
 276   LUA_RETURN(l, LUA_OK);
 277 }
 278
 279 static void lua_socket_poll_event(int fd, short events) {
 280   lua_socket *ls = socketbyfd(fd);
 281   if(!ls || (ls->state == SOCKET_CLOSED))
 282     return;
 283
 284   if(events & (POLLERR | POLLHUP)) {
 285     lua_socket_call_close(ls);
 286     return;
 287   }
 288
 289   switch(ls->state) {
 290     case SOCKET_CONNECTING:
 291       if(events & POLLOUT) {
 292         deregisterhandler(fd, 0);
 293         registerhandler(fd, POLLIN | POLLERR | POLLHUP, lua_socket_poll_event);
 294         ls->state = SOCKET_CONNECTED;
 295
 296         lua_vnpcall(ls, "connect", "");
 297       }
 298       break;
 299     case SOCKET_CONNECTED:
 300       if(events & POLLOUT) {
 301         deregisterhandler(fd, 0);
 302         registerhandler(fd, POLLIN | POLLERR | POLLHUP, lua_socket_poll_event);
 303
 304         lua_vnpcall(ls, "flush", "");
 305       }
 306       if(events & POLLIN) {
 307         char buf[8192 * 2];
 308         int bytesread;
 309
 310         bytesread = read(fd, buf, sizeof(buf));
 311         if((bytesread == -1) && (errno == EAGAIN))
 312           return;
 313
 314         if(bytesread <= 0) {
 315           lua_socket_call_close(ls);
 316          return;
 317         }
 318
 319         lua_vnpcall(ls, "read", "L", buf, (long)bytesread);
 320       }
 321       break;
 322     case SOCKET_LISTENING:
 323       if(events & POLLIN) {
 324         struct sockaddr_un r;
 325         lua_socket *ls2;
 326         unsigned int len = sizeof(r);
 327
 328         int fd2 = accept(fd, (struct sockaddr *)&r, &len);
 329         if(fd2 == -1)
 330           return;
 331
 332         ls2 = (lua_socket *)luamalloc(sizeof(lua_socket));
 333         if(!ls2) {
 334           close(fd2);
 335           return;
 336         }
 337
 338         ls2->fd = fd2;
 339         ls2->state = SOCKET_CONNECTED;
 340         ls2->tag = ls->tag;
 341         ls2->handler = ls->handler;
 342         ls2->parent = ls;
 343
 344         registerluasocket(ls->l, ls2, POLLIN | POLLERR | POLLHUP, 0);
 345         lua_vnpcall(ls, "accept", "l", ls2->identifier);
 346       }
 347       break;
 348   }
 349 }
 350
 351 void lua_socket_closeall(lua_list *l) {
 352   while(l->sockets)
 353     lua_socket_call_close(l->sockets);
 354 }
 355
 356 void lua_registersocketcommands(lua_State *l) {
 357   lua_register(l, "socket_unix_connect", lua_socket_unix_connect);
 358   lua_register(l, "socket_unix_bind", lua_socket_unix_bind);
 359   lua_register(l, "socket_close", lua_socket_close);
 360   lua_register(l, "socket_write", lua_socket_write);
 361 }