Move use_monotonic and friends into event_base

The use_monotonic field used to be a static field set up at library
setup.  Unfortunately, this makes it hard to give the user a way to
make speed/accuracy tradeoffs about time.  Moving it into event_base
should let the clock implementation become configurable.

diff --git a/event-internal.h b/event-internal.h
index d2533fa419f6d9598617dcad5eb603fe29efe755..e7a2afad4d646d755bb8de05032cdfd30c40de0a 100644 (file)
--- a/event-internal.h
+++ b/event-internal.h
@@ -36,6 +36,10 @@ extern "C" {
 
 #include <time.h>
 #include <sys/queue.h>
+#ifdef EVENT__HAVE_MACH_MACH_TIME_H
+/* For mach_timebase_info */
+#include <mach/mach_time.h>
+#endif
 #include "event2/event_struct.h"
 #include "minheap-internal.h"
 #include "evsignal-internal.h"
@@ -251,7 +255,12 @@ struct event_base {
         * too often. */
        struct timeval tv_cache;
 
+#if defined(EVENT__HAVE_MACH_ABSOLUTE_TIME)
+       struct mach_timebase_info mach_timebase_units;
+#endif
 #if defined(HAVE_ANY_MONOTONIC)
+       /** True iff we should use our system's monotonic time implementation */
+       int use_monotonic;
        /** Difference between internal time (maybe from clock_gettime) and
         * gettimeofday. */
        struct timeval tv_clock_diff;

diff --git a/event.c b/event.c
index a8867112c743f81cc7267415d4d7c26234cdcf31..6189993299b6e22617755aee6b7147786732362f 100644 (file)
--- a/event.c
+++ b/event.c
@@ -46,9 +46,6 @@
 #ifdef EVENT__HAVE_UNISTD_H
 #include <unistd.h>
 #endif
-#ifdef EVENT__HAVE_MACH_MACH_TIME_H
-#include <mach/mach_time.h>
-#endif
 #include <ctype.h>
 #include <errno.h>
 #include <signal.h>
@@ -131,10 +128,6 @@ struct event_base *event_global_current_base_ = NULL;
 
 /* Global state */
 
-#ifdef HAVE_ANY_MONOTONIC
-static int use_monotonic;
-#endif
-
 static void *event_self_cbarg_ptr_ = NULL;
 
 /* Prototypes */
@@ -345,19 +338,11 @@ HT_GENERATE(event_debug_map, event_debug_entry, node, hash_debug_entry,
 #define EVENT_BASE_ASSERT_LOCKED(base)         \
        EVLOCK_ASSERT_LOCKED((base)->th_base_lock)
 
-#if defined(EVENT__HAVE_MACH_ABSOLUTE_TIME)
-struct mach_timebase_info mach_timebase_units;
-#endif
-
-/* The first time this function is called, it sets use_monotonic to 1
- * if we have a clock function that supports monotonic time */
+/* Set base->use_monotonic to 1 if we have a clock function that supports
+ * monotonic time */
 static void
-detect_monotonic(void)
+detect_monotonic(struct event_base *base)
 {
-       static int use_monotonic_initialized = 0;
-       if (use_monotonic_initialized)
-               return;
-
 #if defined(EVENT__HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC)
        {
                /* CLOCK_MONOTONIC exists on FreeBSD, Linux, and Solaris.
@@ -366,24 +351,22 @@ detect_monotonic(void)
                struct timespec ts;
 
                if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0)
-                       use_monotonic = 1;
+                       base->use_monotonic = 1;
        }
 #elif defined(EVENT__HAVE_MACH_ABSOLUTE_TIME)
        {
                struct mach_timebase_info mi;
                /* OSX has mach_absolute_time() */
                if (mach_timebase_info(&mi) == 0 && mach_absolute_time() != 0) {
-                       use_monotonic = 1;
+                       base->use_monotonic = 1;
                        /* mach_timebase_info tells us how to convert
                         * mach_absolute_time() into nanoseconds, but we
                         * want to use microseconds instead. */
                        mi.denom *= 1000;
-                       memcpy(&mach_timebase_units, &mi, sizeof(mi));
+                       memcpy(&base->mach_timebase_units, &mi, sizeof(mi));
                }
        }
 #endif
-       use_monotonic_initialized = 1;
-
 }
 
 /* How often (in seconds) do we check for changes in wall clock time relative
@@ -406,7 +389,7 @@ gettime(struct event_base *base, struct timeval *tp)
        }
 
 #ifdef HAVE_ANY_MONOTONIC
-       if (use_monotonic) {
+       if (base->use_monotonic) {
 #if defined(EVENT__HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC)
                struct timespec ts;
                if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1)
@@ -417,8 +400,8 @@ gettime(struct event_base *base, struct timeval *tp)
 #elif defined(EVENT__HAVE_MACH_ABSOLUTE_TIME)
                uint64_t abstime = mach_absolute_time();
                uint64_t usec;
-               usec = (abstime * mach_timebase_units.numer)
-                   / (mach_timebase_units.denom);
+               usec = (abstime * base->mach_timebase_units.numer)
+                   / (base->mach_timebase_units.denom);
                tp->tv_sec = usec / 1000000;
                tp->tv_usec = usec % 1000000;
 #else
@@ -631,7 +614,7 @@ event_base_new_with_config(const struct event_config *cfg)
                event_warn("%s: calloc", __func__);
                return NULL;
        }
-       detect_monotonic();
+       detect_monotonic(base);
        gettime(base, &base->event_tv);
 
        min_heap_ctor_(&base->timeheap);
@@ -2621,7 +2604,7 @@ timeout_correct(struct event_base *base, struct timeval *tv)
        int i;
 
 #ifdef HAVE_ANY_MONOTONIC
-       if (use_monotonic)
+       if (base->use_monotonic)
                return;
 #endif