| 1 | /* |
| 2 | * This file is part of DisOrder. |
| 3 | * Copyright (C) 2004 Richard Kettlewell |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation; either version 2 of the License, or |
| 8 | * (at your option) any later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, but |
| 11 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | * General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write to the Free Software |
| 17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 |
| 18 | * USA |
| 19 | */ |
| 20 | |
| 21 | #ifndef EVENT_H |
| 22 | #define EVENT_H |
| 23 | |
| 24 | typedef struct ev_source ev_source; |
| 25 | |
| 26 | struct rusage; |
| 27 | struct sink; |
| 28 | |
| 29 | ev_source *ev_new(void); |
| 30 | /* create a new event loop */ |
| 31 | |
| 32 | int ev_run(ev_source *ev); |
| 33 | /* run an event loop. If any callback returns nonzero then that value |
| 34 | * is returned. If an error occurs then -1 is returned and @error@ is |
| 35 | * called. */ |
| 36 | |
| 37 | /* file descriptors ***********************************************************/ |
| 38 | |
| 39 | typedef enum { |
| 40 | ev_read, |
| 41 | ev_write, |
| 42 | ev_except, |
| 43 | |
| 44 | ev_nmodes |
| 45 | } ev_fdmode; |
| 46 | |
| 47 | typedef int ev_fd_callback(ev_source *ev, int fd, void *u); |
| 48 | /* signature for fd callback functions */ |
| 49 | |
| 50 | int ev_fd(ev_source *ev, |
| 51 | ev_fdmode mode, |
| 52 | int fd, |
| 53 | ev_fd_callback *callback, |
| 54 | void *u); |
| 55 | /* register a callback on a file descriptor */ |
| 56 | |
| 57 | int ev_fd_cancel(ev_source *ev, |
| 58 | ev_fdmode mode, |
| 59 | int fd); |
| 60 | /* cancel a callback on a file descriptor */ |
| 61 | |
| 62 | int ev_fd_disable(ev_source *ev, |
| 63 | ev_fdmode mode, |
| 64 | int fd); |
| 65 | /* temporarily disable callbacks on a file descriptor */ |
| 66 | |
| 67 | int ev_fd_enable(ev_source *ev, |
| 68 | ev_fdmode mode, |
| 69 | int fd); |
| 70 | /* re-enable callbacks on a file descriptor */ |
| 71 | |
| 72 | /* timeouts *******************************************************************/ |
| 73 | |
| 74 | typedef int ev_timeout_callback(ev_source *ev, |
| 75 | const struct timeval *now, |
| 76 | void *u); |
| 77 | /* signature for timeout callback functions */ |
| 78 | |
| 79 | typedef void *ev_timeout_handle; |
| 80 | |
| 81 | int ev_timeout(ev_source *ev, |
| 82 | ev_timeout_handle *handlep, |
| 83 | const struct timeval *when, |
| 84 | ev_timeout_callback *callback, |
| 85 | void *u); |
| 86 | /* register a timeout callback. If @handlep@ is not a null pointer then a |
| 87 | * handle suitable for ev_timeout_cancel() below is returned through it. */ |
| 88 | |
| 89 | int ev_timeout_cancel(ev_source *ev, |
| 90 | ev_timeout_handle handle); |
| 91 | /* cancel a timeout callback */ |
| 92 | |
| 93 | /* signals ********************************************************************/ |
| 94 | |
| 95 | typedef int ev_signal_callback(ev_source *ev, |
| 96 | int sig, |
| 97 | void *u); |
| 98 | /* signature for signal callback functions */ |
| 99 | |
| 100 | int ev_signal(ev_source *ev, |
| 101 | int sig, |
| 102 | ev_signal_callback *callback, |
| 103 | void *u); |
| 104 | /* register a signal callback */ |
| 105 | |
| 106 | int ev_signal_cancel(ev_source *ev, |
| 107 | int sig); |
| 108 | /* cancel a signal callback */ |
| 109 | |
| 110 | void ev_signal_atfork(ev_source *ev); |
| 111 | /* unhandle and unblock handled signals - call after calling fork and |
| 112 | * then setting @exitfn@ */ |
| 113 | |
| 114 | /* child processes ************************************************************/ |
| 115 | |
| 116 | typedef int ev_child_callback(ev_source *ev, |
| 117 | pid_t pid, |
| 118 | int status, |
| 119 | const struct rusage *rusage, |
| 120 | void *u); |
| 121 | /* signature for child wait callbacks */ |
| 122 | |
| 123 | int ev_child_setup(ev_source *ev); |
| 124 | /* must be called exactly once before @ev_child@ */ |
| 125 | |
| 126 | int ev_child(ev_source *ev, |
| 127 | pid_t pid, |
| 128 | int options, |
| 129 | ev_child_callback *callback, |
| 130 | void *u); |
| 131 | /* register a child callback. @options@ must be 0 or WUNTRACED. */ |
| 132 | |
| 133 | int ev_child_cancel(ev_source *ev, |
| 134 | pid_t pid); |
| 135 | /* cancel a child callback. */ |
| 136 | |
| 137 | /* socket listeners ***********************************************************/ |
| 138 | |
| 139 | typedef int ev_listen_callback(ev_source *ev, |
| 140 | int newfd, |
| 141 | const struct sockaddr *remote, |
| 142 | socklen_t rlen, |
| 143 | void *u); |
| 144 | /* callback when a connection arrives. */ |
| 145 | |
| 146 | int ev_listen(ev_source *ev, |
| 147 | int fd, |
| 148 | ev_listen_callback *callback, |
| 149 | void *u); |
| 150 | /* register a socket listener callback. @bind@ and @listen@ should |
| 151 | * already have been called. */ |
| 152 | |
| 153 | int ev_listen_cancel(ev_source *ev, |
| 154 | int fd); |
| 155 | /* cancel a socket listener callback */ |
| 156 | |
| 157 | /* buffered writer ************************************************************/ |
| 158 | |
| 159 | typedef struct ev_writer ev_writer; |
| 160 | |
| 161 | typedef int ev_error_callback(ev_source *ev, |
| 162 | int fd, |
| 163 | int errno_value, |
| 164 | void *u); |
| 165 | /* called when an error occurs on a writer. Called with @errno_value@ |
| 166 | * of 0 when finished. */ |
| 167 | |
| 168 | ev_writer *ev_writer_new(ev_source *ev, |
| 169 | int fd, |
| 170 | ev_error_callback *callback, |
| 171 | void *u); |
| 172 | /* create a new buffered writer, writing to @fd@. Calls @error@ if an |
| 173 | * error occurs. */ |
| 174 | |
| 175 | int ev_writer_close(ev_writer *w); |
| 176 | /* close a writer (i.e. promise not to write to it any more) */ |
| 177 | |
| 178 | int ev_writer_cancel(ev_writer *w); |
| 179 | /* cancel a writer */ |
| 180 | |
| 181 | int ev_writer_flush(ev_writer *w); |
| 182 | /* attempt to flush the buffer */ |
| 183 | |
| 184 | struct sink *ev_writer_sink(ev_writer *w) attribute((const)); |
| 185 | /* return a sink for the writer - use this to actually write to it */ |
| 186 | |
| 187 | /* buffered reader ************************************************************/ |
| 188 | |
| 189 | typedef struct ev_reader ev_reader; |
| 190 | |
| 191 | typedef int ev_reader_callback(ev_source *ev, |
| 192 | ev_reader *reader, |
| 193 | int fd, |
| 194 | void *ptr, |
| 195 | size_t bytes, |
| 196 | int eof, |
| 197 | void *u); |
| 198 | /* Called when data is read or an error occurs. @ptr@ and @bytes@ |
| 199 | * indicate the amount of data available. @eof@ will be 1 at eof. */ |
| 200 | |
| 201 | ev_reader *ev_reader_new(ev_source *ev, |
| 202 | int fd, |
| 203 | ev_reader_callback *callback, |
| 204 | ev_error_callback *error_callback, |
| 205 | void *u); |
| 206 | /* register a new reader. @callback@ will be called whenever data is |
| 207 | * available. */ |
| 208 | |
| 209 | void ev_reader_buffer(ev_reader *r, size_t nbytes); |
| 210 | /* specify a buffer size *case */ |
| 211 | |
| 212 | void ev_reader_consume(ev_reader *r, size_t nbytes); |
| 213 | /* consume @nbytes@ bytes. */ |
| 214 | |
| 215 | int ev_reader_cancel(ev_reader *r); |
| 216 | /* cancel a reader */ |
| 217 | |
| 218 | int ev_reader_disable(ev_reader *r); |
| 219 | /* disable reading */ |
| 220 | |
| 221 | int ev_reader_incomplete(ev_reader *r); |
| 222 | /* callback didn't fully process buffer, but would like another |
| 223 | * callback (used where processing more would block too long) */ |
| 224 | |
| 225 | int ev_reader_enable(ev_reader *r); |
| 226 | /* enable reading. If there is unconsumed data then you get a |
| 227 | * callback next time round the event loop even if nothing new has |
| 228 | * been read. |
| 229 | * |
| 230 | * The idea is in your read callback you come across a line (or |
| 231 | * whatever) that can't be processed immediately. So you set up |
| 232 | * processing and disable reading. Later when you finish processing |
| 233 | * you re-enable. You'll automatically get another callback pretty |
| 234 | * much direct from the event loop (not from inside ev_reader_enable) |
| 235 | * so you can handle the next line (or whatever) if the whole thing |
| 236 | * has in fact already arrived. |
| 237 | */ |
| 238 | |
| 239 | #endif /* EVENT_H */ |
| 240 | |
| 241 | /* |
| 242 | Local Variables: |
| 243 | c-basic-offset:2 |
| 244 | comment-column:40 |
| 245 | fill-column:79 |
| 246 | End: |
| 247 | */ |