libs/nixio/src/io.c

   1 /*
   2  * nixio - Linux I/O library for lua
   3  *
   4  *   Copyright (C) 2009 Steven Barth <steven@midlink.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #include "nixio.h"
  20 #include <errno.h>
  21 #include <stdlib.h>
  22 #include <stdio.h>
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25 #include <arpa/inet.h>
  26 #include "nixio.h"
  27
  28
  29
  30 /**
  31  * send() / sendto() helper
  32  */
  33 static int nixio_sock__sendto(lua_State *L, int to) {
  34         nixio_sock *sock = nixio__checksock(L);
  35         struct sockaddr *addr = NULL;
  36         socklen_t alen = 0;
  37
  38         if (to) {
  39                 const char *address = luaL_checklstring(L, 3, NULL);
  40                 uint16_t port = (uint16_t)luaL_checkinteger(L, 4);
  41                 struct sockaddr_storage addrstor;
  42                 addr = (struct sockaddr*)&addrstor;
  43                 if (sock->domain == AF_INET) {
  44                         struct sockaddr_in *inetaddr = (struct sockaddr_in *)addr;
  45                         if (inet_pton(sock->domain, address, &inetaddr->sin_addr) < 0) {
  46                                 return luaL_argerror(L, 3, "invalid address");
  47                         }
  48                         inetaddr->sin_port = htons(port);
  49                         alen = sizeof(*inetaddr);
  50                 } else if (sock->domain == AF_INET6) {
  51                         struct sockaddr_in6 *inet6addr = (struct sockaddr_in6 *)addr;
  52                         if (inet_pton(sock->domain, address, &inet6addr->sin6_addr) < 0) {
  53                                 return luaL_argerror(L, 3, "invalid address");
  54                         }
  55                         inet6addr->sin6_port = htons(port);
  56                         alen = sizeof(*inet6addr);
  57                 } else {
  58                         return luaL_argerror(L, 1, "supported families: inet, inet6");
  59                 }
  60         }
  61
  62         size_t len;
  63         ssize_t sent;
  64         const char *data = luaL_checklstring(L, 2, &len);
  65         do {
  66                 sent = sendto(sock->fd, data, len, 0, addr, alen);
  67         } while(sent == -1 && errno == EINTR);
  68         if (sent >= 0) {
  69                 lua_pushinteger(L, sent);
  70                 return 1;
  71         } else {
  72                 return nixio__perror(L);
  73         }
  74 }
  75
  76 /**
  77  * send(data)
  78  */
  79 static int nixio_sock_send(lua_State *L) {
  80         return nixio_sock__sendto(L, 0);
  81 }
  82
  83 /**
  84  * sendto(data, address, port)
  85  */
  86 static int nixio_sock_sendto(lua_State *L) {
  87         return nixio_sock__sendto(L, 1);
  88 }
  89
  90
  91 /**
  92  * recv() / recvfrom() helper
  93  */
  94 static int nixio_sock__recvfrom(lua_State *L, int from) {
  95         nixio_sock *sock = nixio__checksock(L);
  96         char buffer[NIXIO_BUFFERSIZE];
  97         struct sockaddr_storage addrobj;
  98         int req = luaL_checkinteger(L, 2);
  99         int readc;
 100
 101         if (from && sock->domain != AF_INET && sock->domain != AF_INET6) {
 102                 return luaL_argerror(L, 1, "supported families: inet, inet6");
 103         }
 104
 105         struct sockaddr *addr = (from) ? (struct sockaddr*)&addrobj : NULL;
 106         socklen_t alen = (from) ? sizeof(addrobj) : 0;
 107
 108         /* We limit the readsize to NIXIO_BUFFERSIZE */
 109         req = (req > NIXIO_BUFFERSIZE) ? NIXIO_BUFFERSIZE : req;
 110
 111         do {
 112                 readc = recvfrom(sock->fd, buffer, req, 0, addr, &alen);
 113         } while (readc == -1 && errno == EINTR);
 114
 115         if (readc < 0) {
 116                 return nixio__perror(L);
 117         } else {
 118                 lua_pushlstring(L, buffer, readc);
 119
 120                 if (!from) {
 121                         return 1;
 122                 } else {
 123                         char ipaddr[INET6_ADDRSTRLEN];
 124                         void *binaddr;
 125                         uint16_t port;
 126
 127                         if (addrobj.ss_family == AF_INET) {
 128                                 struct sockaddr_in *inetaddr = (struct sockaddr_in*)addr;
 129                                 port = inetaddr->sin_port;
 130                                 binaddr = &inetaddr->sin_addr;
 131                         } else if (addrobj.ss_family == AF_INET6) {
 132                                 struct sockaddr_in6 *inet6addr = (struct sockaddr_in6*)addr;
 133                                 port = inet6addr->sin6_port;
 134                                 binaddr = &inet6addr->sin6_addr;
 135                         } else {
 136                                 return luaL_error(L, "unknown address family");
 137                         }
 138
 139                         if (!inet_ntop(addrobj.ss_family, binaddr, ipaddr, sizeof(ipaddr))) {
 140                                 return nixio__perror(L);
 141                         }
 142
 143                         lua_pushstring(L, ipaddr);
 144                         lua_pushinteger(L, ntohs(port));
 145
 146                         return 3;
 147                 }
 148         }
 149 }
 150
 151 /**
 152  * recv(count)
 153  */
 154 static int nixio_sock_recv(lua_State *L) {
 155         return nixio_sock__recvfrom(L, 0);
 156 }
 157
 158 /**
 159  * recvfrom(count)
 160  */
 161 static int nixio_sock_recvfrom(lua_State *L) {
 162         return nixio_sock__recvfrom(L, 1);
 163 }
 164
 165
 166 /* module table */
 167 static const luaL_reg M[] = {
 168         {"send",        nixio_sock_send},
 169         {"sendto",      nixio_sock_sendto},
 170         {"recv",        nixio_sock_recv},
 171         {"recvfrom",nixio_sock_recvfrom},
 172         {NULL,                  NULL}
 173 };
 174
 175 void nixio_open_io(lua_State *L) {
 176         lua_pushvalue(L, -2);
 177         luaL_register(L, NULL, M);
 178         lua_pop(L, 1);
 179 }