src/systemd/sd-event.h

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 #ifndef foosdeventhfoo
   4 #define foosdeventhfoo
   5
   6 /***
   7   This file is part of systemd.
   8
   9   Copyright 2013 Lennart Poettering
  10
  11   systemd is free software; you can redistribute it and/or modify it
  12   under the terms of the GNU Lesser General Public License as published by
  13   the Free Software Foundation; either version 2.1 of the License, or
  14   (at your option) any later version.
  15
  16   systemd is distributed in the hope that it will be useful, but
  17   WITHOUT ANY WARRANTY; without even the implied warranty of
  18   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19   Lesser General Public License for more details.
  20
  21   You should have received a copy of the GNU Lesser General Public License
  22   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  23 ***/
  24
  25 #include <inttypes.h>
  26 #include <signal.h>
  27 #include <sys/epoll.h>
  28 #include <sys/signalfd.h>
  29 #include <sys/types.h>
  30
  31 #include "_sd-common.h"
  32
  33 /*
  34   Why is this better than pure epoll?
  35
  36   - Supports event source prioritization
  37   - Scales better with a large number of time events because it does not require one timerfd each
  38   - Automatically tries to coalesce timer events system-wide
  39   - Handles signals and child PIDs
  40 */
  41
  42 _SD_BEGIN_DECLARATIONS;
  43
  44 typedef struct sd_event sd_event;
  45 typedef struct sd_event_source sd_event_source;
  46
  47 enum {
  48         SD_EVENT_OFF = 0,
  49         SD_EVENT_ON = 1,
  50         SD_EVENT_ONESHOT = -1
  51 };
  52
  53 enum {
  54         SD_EVENT_INITIAL,
  55         SD_EVENT_ARMED,
  56         SD_EVENT_PENDING,
  57         SD_EVENT_RUNNING,
  58         SD_EVENT_EXITING,
  59         SD_EVENT_FINISHED,
  60         SD_EVENT_PREPARING,
  61 };
  62
  63 enum {
  64         /* And everything in-between and outside is good too */
  65         SD_EVENT_PRIORITY_IMPORTANT = -100,
  66         SD_EVENT_PRIORITY_NORMAL = 0,
  67         SD_EVENT_PRIORITY_IDLE = 100
  68 };
  69
  70 typedef int (*sd_event_handler_t)(sd_event_source *s, void *userdata);
  71 typedef int (*sd_event_io_handler_t)(sd_event_source *s, int fd, uint32_t revents, void *userdata);
  72 typedef int (*sd_event_time_handler_t)(sd_event_source *s, uint64_t usec, void *userdata);
  73 typedef int (*sd_event_signal_handler_t)(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata);
  74 typedef int (*sd_event_child_handler_t)(sd_event_source *s, const siginfo_t *si, void *userdata);
  75
  76 int sd_event_default(sd_event **e);
  77
  78 int sd_event_new(sd_event **e);
  79 sd_event* sd_event_ref(sd_event *e);
  80 sd_event* sd_event_unref(sd_event *e);
  81
  82 int sd_event_add_io(sd_event *e, sd_event_source **s, int fd, uint32_t events, sd_event_io_handler_t callback, void *userdata);
  83 int sd_event_add_time(sd_event *e, sd_event_source **s, clockid_t clock, uint64_t usec, uint64_t accuracy, sd_event_time_handler_t callback, void *userdata);
  84 int sd_event_add_signal(sd_event *e, sd_event_source **s, int sig, sd_event_signal_handler_t callback, void *userdata);
  85 int sd_event_add_child(sd_event *e, sd_event_source **s, pid_t pid, int options, sd_event_child_handler_t callback, void *userdata);
  86 int sd_event_add_defer(sd_event *e, sd_event_source **s, sd_event_handler_t callback, void *userdata);
  87 int sd_event_add_post(sd_event *e, sd_event_source **s, sd_event_handler_t callback, void *userdata);
  88 int sd_event_add_exit(sd_event *e, sd_event_source **s, sd_event_handler_t callback, void *userdata);
  89
  90 int sd_event_prepare(sd_event *e);
  91 int sd_event_wait(sd_event *e, uint64_t usec);
  92 int sd_event_dispatch(sd_event *e);
  93 int sd_event_run(sd_event *e, uint64_t usec);
  94 int sd_event_loop(sd_event *e);
  95 int sd_event_exit(sd_event *e, int code);
  96
  97 int sd_event_now(sd_event *e, clockid_t clock, uint64_t *usec);
  98
  99 int sd_event_get_fd(sd_event *e);
 100 int sd_event_get_state(sd_event *e);
 101 int sd_event_get_tid(sd_event *e, pid_t *tid);
 102 int sd_event_get_exit_code(sd_event *e, int *code);
 103 int sd_event_set_watchdog(sd_event *e, int b);
 104 int sd_event_get_watchdog(sd_event *e);
 105
 106 sd_event_source* sd_event_source_ref(sd_event_source *s);
 107 sd_event_source* sd_event_source_unref(sd_event_source *s);
 108
 109 sd_event *sd_event_source_get_event(sd_event_source *s);
 110 void* sd_event_source_get_userdata(sd_event_source *s);
 111 void* sd_event_source_set_userdata(sd_event_source *s, void *userdata);
 112
 113 int sd_event_source_set_description(sd_event_source *s, const char *description);
 114 int sd_event_source_get_description(sd_event_source *s, const char **description);
 115 int sd_event_source_set_prepare(sd_event_source *s, sd_event_handler_t callback);
 116 int sd_event_source_get_pending(sd_event_source *s);
 117 int sd_event_source_get_priority(sd_event_source *s, int64_t *priority);
 118 int sd_event_source_set_priority(sd_event_source *s, int64_t priority);
 119 int sd_event_source_get_enabled(sd_event_source *s, int *enabled);
 120 int sd_event_source_set_enabled(sd_event_source *s, int enabled);
 121 int sd_event_source_get_io_fd(sd_event_source *s);
 122 int sd_event_source_set_io_fd(sd_event_source *s, int fd);
 123 int sd_event_source_get_io_events(sd_event_source *s, uint32_t* events);
 124 int sd_event_source_set_io_events(sd_event_source *s, uint32_t events);
 125 int sd_event_source_get_io_revents(sd_event_source *s, uint32_t* revents);
 126 int sd_event_source_get_time(sd_event_source *s, uint64_t *usec);
 127 int sd_event_source_set_time(sd_event_source *s, uint64_t usec);
 128 int sd_event_source_get_time_accuracy(sd_event_source *s, uint64_t *usec);
 129 int sd_event_source_set_time_accuracy(sd_event_source *s, uint64_t usec);
 130 int sd_event_source_get_time_clock(sd_event_source *s, clockid_t *clock);
 131 int sd_event_source_get_signal(sd_event_source *s);
 132 int sd_event_source_get_child_pid(sd_event_source *s, pid_t *pid);
 133
 134 /* Define helpers so that __attribute__((cleanup(sd_event_unrefp))) and similar may be used. */
 135 _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_event, sd_event_unref);
 136 _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_event_source, sd_event_source_unref);
 137
 138 _SD_END_DECLARATIONS;
 139
 140 #endif