| 1 | /*************************************************************************** |
| 2 | * Copyright (C) 2006 by Gerd v. Egidy * |
| 3 | * gve@intra2net.com * |
| 4 | * * |
| 5 | * This library is free software; you can redistribute it and/or modify * |
| 6 | * it under the terms of the GNU Lesser General Public License version * |
| 7 | * 2.1 as published by the Free Software Foundation. * |
| 8 | * * |
| 9 | * This library is distributed in the hope that it will be useful, * |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of * |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * |
| 12 | * GNU Lesser General Public License for more details. * |
| 13 | * * |
| 14 | * You should have received a copy of the GNU Lesser General Public * |
| 15 | * License along with this program; if not, write to the * |
| 16 | * Free Software Foundation, Inc., * |
| 17 | * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * |
| 18 | ***************************************************************************/ |
| 19 | |
| 20 | #include <stdio.h> |
| 21 | #include <errno.h> |
| 22 | #include <stdlib.h> |
| 23 | #include <unistd.h> |
| 24 | #include <sys/types.h> |
| 25 | #include <sys/socket.h> |
| 26 | #include <sys/un.h> |
| 27 | #include <sys/time.h> |
| 28 | #include <arpa/inet.h> |
| 29 | #include <netinet/in.h> |
| 30 | #include <netdb.h> |
| 31 | #include <fcntl.h> |
| 32 | #include <time.h> |
| 33 | #include <pwd.h> |
| 34 | #include <grp.h> |
| 35 | |
| 36 | #include <sstream> |
| 37 | |
| 38 | #include "socket_handler.hxx" |
| 39 | #include "t2n_exception.hxx" |
| 40 | |
| 41 | using namespace std; |
| 42 | |
| 43 | namespace libt2n |
| 44 | { |
| 45 | |
| 46 | void socket_handler::set_socket_options(int sock) |
| 47 | { |
| 48 | int i=1; |
| 49 | |
| 50 | /* fast reuse enable */ |
| 51 | if (setsockopt(sock,SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i)) < 0) |
| 52 | { |
| 53 | string err="error setting socket option: "; |
| 54 | err+=strerror(errno); |
| 55 | log(error, err); |
| 56 | throw t2n_communication_error(err); |
| 57 | } |
| 58 | |
| 59 | /* keepalive enable */ |
| 60 | if (setsockopt(sock,SOL_SOCKET, SO_KEEPALIVE, &i, sizeof(i)) < 0) |
| 61 | { |
| 62 | string err="error setting socket option: "; |
| 63 | err+=strerror(errno); |
| 64 | log(error, err); |
| 65 | throw t2n_communication_error(err); |
| 66 | } |
| 67 | |
| 68 | /* close on exec */ |
| 69 | int fdflags; |
| 70 | fdflags=fcntl(sock,F_GETFD, 0); |
| 71 | if (fdflags < 0) |
| 72 | { |
| 73 | string err="fcntl error on socket: "; |
| 74 | err+=strerror(errno); |
| 75 | log(error, err); |
| 76 | throw t2n_communication_error(err); |
| 77 | } |
| 78 | fdflags |= FD_CLOEXEC; |
| 79 | if (fcntl(sock,F_SETFD,fdflags) < 0) |
| 80 | { |
| 81 | string err="fcntl error on socket: "; |
| 82 | err+=strerror(errno); |
| 83 | log(error, err); |
| 84 | throw t2n_communication_error(err); |
| 85 | } |
| 86 | |
| 87 | /* non-blocking mode */ |
| 88 | int flflags; |
| 89 | flflags=fcntl(sock,F_GETFL,0); |
| 90 | if (flflags < 0) |
| 91 | { |
| 92 | string err="fcntl error on socket: "; |
| 93 | err+=strerror(errno); |
| 94 | log(error, err); |
| 95 | throw t2n_communication_error(err); |
| 96 | } |
| 97 | flflags |= O_NONBLOCK; |
| 98 | if (fcntl(sock,F_SETFL,flflags) < 0) |
| 99 | { |
| 100 | string err="fcntl error on socket: "; |
| 101 | err+=strerror(errno); |
| 102 | log(error, err); |
| 103 | throw t2n_communication_error(err); |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | void socket_handler::close() |
| 108 | { |
| 109 | ::close(sock); |
| 110 | } |
| 111 | |
| 112 | bool socket_handler::data_waiting(long long usec_timeout) |
| 113 | { |
| 114 | // just our socket |
| 115 | fd_set active_fd_set; |
| 116 | FD_ZERO (&active_fd_set); |
| 117 | FD_SET (sock, &active_fd_set); |
| 118 | |
| 119 | /* set timeout */ |
| 120 | struct timeval tval; |
| 121 | struct timeval *timeout_ptr; |
| 122 | |
| 123 | if (usec_timeout == -1) |
| 124 | timeout_ptr = NULL; |
| 125 | else |
| 126 | { |
| 127 | timeout_ptr = &tval; |
| 128 | |
| 129 | // timeout von long long usec in int sec + int usec umrechnen |
| 130 | tval.tv_sec = usec_timeout / 1000000; |
| 131 | tval.tv_usec = usec_timeout % 1000000; |
| 132 | } |
| 133 | |
| 134 | if(select (FD_SETSIZE, &active_fd_set, NULL, NULL, timeout_ptr) > 0) |
| 135 | return true; |
| 136 | else |
| 137 | return false; |
| 138 | } |
| 139 | |
| 140 | bool socket_handler::fill_buffer(std::string& buffer, long long usec_timeout) |
| 141 | { |
| 142 | // fast path for timeout==-1 |
| 143 | if (usec_timeout==-1 || data_waiting(usec_timeout)) |
| 144 | return fill_buffer(buffer); |
| 145 | else |
| 146 | return false; |
| 147 | } |
| 148 | |
| 149 | bool socket_handler::fill_buffer(std::string& buffer) |
| 150 | { |
| 151 | bool try_again=false; |
| 152 | |
| 153 | char socket_buffer[recv_buffer_size]; |
| 154 | |
| 155 | int nbytes = read (sock, socket_buffer, recv_buffer_size); |
| 156 | if (nbytes < 0) |
| 157 | { |
| 158 | if (errno == EAGAIN) |
| 159 | return false; // no data was waiting |
| 160 | else if (errno == EINTR) |
| 161 | { |
| 162 | // interrupted, try again |
| 163 | try_again=true; |
| 164 | } |
| 165 | else |
| 166 | { |
| 167 | log(error,string("error reading from socket : ")+strerror(errno)); |
| 168 | // TODO: exception? |
| 169 | return false; |
| 170 | } |
| 171 | } |
| 172 | |
| 173 | // End-of-file |
| 174 | if (nbytes == 0 && !try_again) |
| 175 | { |
| 176 | close(); |
| 177 | return false; |
| 178 | } |
| 179 | |
| 180 | // Data read -> store it |
| 181 | if (nbytes > 0) |
| 182 | buffer.assign(socket_buffer,nbytes); |
| 183 | |
| 184 | // more data waiting -> recurse |
| 185 | if (data_waiting()) |
| 186 | fill_buffer(buffer); |
| 187 | |
| 188 | if (nbytes > 0) |
| 189 | return true; |
| 190 | else |
| 191 | return false; |
| 192 | } |
| 193 | |
| 194 | void socket_handler::write(const std::string& data) |
| 195 | { |
| 196 | int offset = 0; |
| 197 | while (offset < data.size()) |
| 198 | { |
| 199 | unsigned int write_size=write_block_size; |
| 200 | |
| 201 | if (offset+write_size > data.size()) |
| 202 | write_size = data.size()-offset; |
| 203 | |
| 204 | int rtn; |
| 205 | while ((rtn=::write(sock, data.data()+offset, write_size)) && |
| 206 | rtn == -1 && (errno == EAGAIN || errno == EINTR)) |
| 207 | { |
| 208 | usleep (80000); |
| 209 | log(debug,"resuming write() call after EAGAIN or EINTR"); |
| 210 | } |
| 211 | |
| 212 | if (rtn == -1) |
| 213 | { |
| 214 | log(error,string("write() returned ")+strerror(errno)); |
| 215 | // TODO: exception? |
| 216 | return; |
| 217 | } |
| 218 | else if (rtn != write_size) |
| 219 | { |
| 220 | ostringstream msg; |
| 221 | msg << "write() wrote " << rtn << " bytes, should have been " |
| 222 | << write_size << " (complete: " << data.size() << ")"; |
| 223 | |
| 224 | log(error,msg.str()); |
| 225 | |
| 226 | // TODO: exception? |
| 227 | return; |
| 228 | } |
| 229 | |
| 230 | offset += write_size; |
| 231 | } |
| 232 | |
| 233 | return; |
| 234 | } |
| 235 | |
| 236 | } |