lib/tevent/tevent_liboop.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    main select loop and event handling
   4    wrapper for http://liboop.org/
   5
   6    Copyright (C) Stefan Metzmacher 2005
   7
   8      ** NOTE! The following LGPL license applies to the tevent
   9      ** library. This does NOT imply that all of Samba is released
  10      ** under the LGPL
  11
  12    This library is free software; you can redistribute it and/or
  13    modify it under the terms of the GNU Lesser General Public
  14    License as published by the Free Software Foundation; either
  15    version 3 of the License, or (at your option) any later version.
  16
  17    This library is distributed in the hope that it will be useful,
  18    but WITHOUT ANY WARRANTY; without even the implied warranty of
  19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20    Lesser General Public License for more details.
  21
  22    You should have received a copy of the GNU Lesser General Public
  23    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  24 */
  25
  26 #include "events.h"
  27 #include "events_internal.h"
  28
  29 #include <oop.h>
  30
  31 /*
  32  !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  33
  34  NOTE: this code compiles fine, but is completely *UNTESTED*
  35        and is only committed as an example
  36
  37  !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  38 */
  39
  40 static int oop_event_context_destructor(struct tevent_context *ev)
  41 {
  42         oop_source_sys *oop_sys = ev->additional_data;
  43
  44         oop_sys_delete(oop_sys);
  45
  46         return 0;
  47 }
  48
  49 /*
  50   create a oop_event_context structure.
  51 */
  52 static int oop_event_context_init(struct tevent_context *ev, void *private_data)
  53 {
  54         oop_source_sys *oop_sys = private_data;
  55
  56         if (!oop_sys) {
  57                 oop_sys = oop_sys_new();
  58                 if (!oop_sys) {
  59                         return -1;
  60                 }
  61
  62                 talloc_set_destructor(ev, oop_event_context_destructor);
  63         }
  64
  65         ev->additional_data = oop_sys;
  66
  67         return 0;
  68 }
  69
  70 static void *oop_event_fd_handler(oop_source *oop, int fd, oop_event oop_type, void *ptr)
  71 {
  72         struct tevent_fd *fde = ptr;
  73
  74         if (fd != fde->fd) return OOP_ERROR;
  75
  76         switch(oop_type) {
  77                 case OOP_READ:
  78                         fde->handler(fde->event_ctx, fde, EVENT_FD_READ, fde->private_data);
  79                         return OOP_CONTINUE;
  80                 case OOP_WRITE:
  81                         fde->handler(fde->event_ctx, fde, EVENT_FD_WRITE, fde->private_data);
  82                         return OOP_CONTINUE;
  83                 case OOP_EXCEPTION:
  84                         return OOP_ERROR;
  85                 case OOP_NUM_EVENTS:
  86                         return OOP_ERROR;
  87         }
  88
  89         return OOP_ERROR;
  90 }
  91
  92 /*
  93   destroy an fd_event
  94 */
  95 static int oop_event_fd_destructor(struct tevent_fd *fde)
  96 {
  97         struct tevent_context *ev = fde->event_ctx;
  98         oop_source_sys *oop_sys = ev->additional_data;
  99         oop_source *oop = oop_sys_source(oop_sys);
 100
 101         if (fde->flags & EVENT_FD_READ)
 102                 oop->cancel_fd(oop, fde->fd, OOP_READ);
 103         if (fde->flags & EVENT_FD_WRITE)
 104                 oop->cancel_fd(oop, fde->fd, OOP_WRITE);
 105
 106         if (fde->flags & EVENT_FD_AUTOCLOSE) {
 107                 close(fde->fd);
 108                 fde->fd = -1;
 109         }
 110
 111         return 0;
 112 }
 113
 114 /*
 115   add a fd based event
 116   return NULL on failure (memory allocation error)
 117 */
 118 static struct tevent_fd *oop_event_add_fd(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
 119                                          int fd, uint16_t flags,
 120                                          event_fd_handler_t handler,
 121                                          void *private_data)
 122 {
 123         struct tevent_fd *fde;
 124         oop_source_sys *oop_sys = ev->additional_data;
 125         oop_source *oop = oop_sys_source(oop_sys);
 126
 127         fde = talloc(mem_ctx?mem_ctx:ev, struct tevent_fd);
 128         if (!fde) return NULL;
 129
 130         fde->event_ctx          = ev;
 131         fde->fd                 = fd;
 132         fde->flags              = flags;
 133         fde->handler            = handler;
 134         fde->private_data       = private_data;
 135         fde->additional_flags   = 0;
 136         fde->additional_data    = NULL;
 137
 138         if (fde->flags & EVENT_FD_READ)
 139                 oop->on_fd(oop, fde->fd, OOP_READ, oop_event_fd_handler, fde);
 140         if (fde->flags & EVENT_FD_WRITE)
 141                 oop->on_fd(oop, fde->fd, OOP_WRITE, oop_event_fd_handler, fde);
 142
 143         talloc_set_destructor(fde, oop_event_fd_destructor);
 144
 145         return fde;
 146 }
 147
 148 /*
 149   return the fd event flags
 150 */
 151 static uint16_t oop_event_get_fd_flags(struct tevent_fd *fde)
 152 {
 153         return fde->flags;
 154 }
 155
 156 /*
 157   set the fd event flags
 158 */
 159 static void oop_event_set_fd_flags(struct tevent_fd *fde, uint16_t flags)
 160 {
 161         oop_source_sys *oop_sys;
 162         oop_source *oop;
 163
 164         oop_sys = fde->event_ctx->additional_data;
 165         oop = oop_sys_source(oop_sys);
 166
 167         if ((fde->flags & EVENT_FD_READ)&&(!(flags & EVENT_FD_READ)))
 168                 oop->cancel_fd(oop, fde->fd, OOP_READ);
 169
 170         if ((!(fde->flags & EVENT_FD_READ))&&(flags & EVENT_FD_READ))
 171                 oop->on_fd(oop, fde->fd, OOP_READ, oop_event_fd_handler, fde);
 172
 173         if ((fde->flags & EVENT_FD_WRITE)&&(!(flags & EVENT_FD_WRITE)))
 174                 oop->cancel_fd(oop, fde->fd, OOP_WRITE);
 175
 176         if ((!(fde->flags & EVENT_FD_WRITE))&&(flags & EVENT_FD_WRITE))
 177                 oop->on_fd(oop, fde->fd, OOP_WRITE, oop_event_fd_handler, fde);
 178
 179         fde->flags = flags;
 180 }
 181
 182 static int oop_event_timed_destructor(struct tevent_timer *te);
 183
 184 static int oop_event_timed_deny_destructor(struct tevent_timer *te)
 185 {
 186         return -1;
 187 }
 188
 189 static void *oop_event_timed_handler(oop_source *oop, struct timeval t, void *ptr)
 190 {
 191         struct tevent_timer *te = ptr;
 192
 193         /* deny the handler to free the event */
 194         talloc_set_destructor(te, oop_event_timed_deny_destructor);
 195         te->handler(te->event_ctx, te, t, te->private_data);
 196
 197         talloc_set_destructor(te, oop_event_timed_destructor);
 198         talloc_free(te);
 199
 200         return OOP_CONTINUE;
 201 }
 202
 203 /*
 204   destroy a timed event
 205 */
 206 static int oop_event_timed_destructor(struct tevent_timer *te)
 207 {
 208         struct tevent_context *ev = te->event_ctx;
 209         oop_source_sys *oop_sys = ev->additional_data;
 210         oop_source *oop = oop_sys_source(oop_sys);
 211
 212         oop->cancel_time(oop, te->next_event, oop_event_timed_handler, te);
 213
 214         return 0;
 215 }
 216
 217 /*
 218   add a timed event
 219   return NULL on failure (memory allocation error)
 220 */
 221 static struct tevent_timer *oop_event_add_timed(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
 222                                                struct timeval next_event,
 223                                                event_timed_handler_t handler,
 224                                                void *private_data)
 225 {
 226         oop_source_sys *oop_sys = ev->additional_data;
 227         oop_source *oop = oop_sys_source(oop_sys);
 228         struct tevent_timer *te;
 229
 230         te = talloc(mem_ctx?mem_ctx:ev, struct tevent_timer);
 231         if (te == NULL) return NULL;
 232
 233         te->event_ctx           = ev;
 234         te->next_event          = next_event;
 235         te->handler             = handler;
 236         te->private_data        = private_data;
 237         te->additional_data     = NULL;
 238
 239         oop->on_time(oop, te->next_event, oop_event_timed_handler, te);
 240
 241         talloc_set_destructor(te, oop_event_timed_destructor);
 242
 243         return te;
 244 }
 245
 246 /*
 247   do a single event loop using the events defined in ev
 248 */
 249 static int oop_event_loop_once(struct tevent_context *ev)
 250 {
 251         void *oop_ret;
 252         oop_source_sys *oop_sys = ev->additional_data;
 253
 254         oop_ret = oop_sys_run_once(oop_sys);
 255         if (oop_ret == OOP_CONTINUE) {
 256                 return 0;
 257         }
 258
 259         return -1;
 260 }
 261
 262 /*
 263   return on failure or (with 0) if all fd events are removed
 264 */
 265 static int oop_event_loop_wait(struct tevent_context *ev)
 266 {
 267         void *oop_ret;
 268         oop_source_sys *oop_sys = ev->additional_data;
 269
 270         oop_ret = oop_sys_run(oop_sys);
 271         if (oop_ret == OOP_CONTINUE) {
 272                 return 0;
 273         }
 274
 275         return -1;
 276 }
 277
 278 static const struct event_ops event_oop_ops = {
 279         .context_init   = oop_event_context_init,
 280         .add_fd         = oop_event_add_fd,
 281         .get_fd_flags   = oop_event_get_fd_flags,
 282         .set_fd_flags   = oop_event_set_fd_flags,
 283         .add_timer      = oop_event_add_timed,
 284         .add_signal     = common_event_add_signal,
 285         .loop_once      = oop_event_loop_once,
 286         .loop_wait      = oop_event_loop_wait,
 287 };
 288
 289 const struct event_ops *event_liboop_get_ops(void)
 290 {
 291         return &event_oop_ops;
 292 }