diff options
Diffstat (limited to 'src/timer.c')
| -rw-r--r-- | src/timer.c | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/src/timer.c b/src/timer.c new file mode 100644 index 0000000..644eeab --- /dev/null +++ b/src/timer.c @@ -0,0 +1,245 @@ +/* + * iperf, Copyright (c) 2014, The Regents of the University of + * California, through Lawrence Berkeley National Laboratory (subject + * to receipt of any required approvals from the U.S. Dept. of + * Energy). All rights reserved. + * + * If you have questions about your rights to use or distribute this + * software, please contact Berkeley Lab's Technology Transfer + * Department at TTD@lbl.gov. + * + * NOTICE. This software is owned by the U.S. Department of Energy. + * As such, the U.S. Government has been granted for itself and others + * acting on its behalf a paid-up, nonexclusive, irrevocable, + * worldwide license in the Software to reproduce, prepare derivative + * works, and perform publicly and display publicly. Beginning five + * (5) years after the date permission to assert copyright is obtained + * from the U.S. Department of Energy, and subject to any subsequent + * five (5) year renewals, the U.S. Government is granted for itself + * and others acting on its behalf a paid-up, nonexclusive, + * irrevocable, worldwide license in the Software to reproduce, + * prepare derivative works, distribute copies to the public, perform + * publicly and display publicly, and to permit others to do so. + * + * This code is distributed under a BSD style license, see the LICENSE + * file for complete information. + * + * Based on timers.c by Jef Poskanzer. Used with permission. + */ + +#include <sys/types.h> +#include <stdlib.h> + +#include "timer.h" +#include "iperf_time.h" + +static Timer* timers = NULL; +static Timer* free_timers = NULL; + +TimerClientData JunkClientData; + + + +/* This is an efficiency tweak. All the routines that need to know the +** current time get passed a pointer to a struct iperf_time. If it's non-NULL +** it gets used, otherwise we do our own iperf_time_now() to fill it in. +** This lets the caller avoid extraneous iperf_time_now()s when efficiency +** is needed, and not bother with the extra code when efficiency doesn't +** matter too much. +*/ +static void +getnow( struct iperf_time* nowP, struct iperf_time* nowP2 ) +{ + if ( nowP != NULL ) + *nowP2 = *nowP; + else + iperf_time_now(nowP2); +} + + +static void +list_add( Timer* t ) +{ + Timer* t2; + Timer* t2prev; + + if ( timers == NULL ) { + /* The list is empty. */ + timers = t; + t->prev = t->next = NULL; + } else { + if (iperf_time_compare(&t->time, &timers->time) < 0) { + /* The new timer goes at the head of the list. */ + t->prev = NULL; + t->next = timers; + timers->prev = t; + timers = t; + } else { + /* Walk the list to find the insertion point. */ + for ( t2prev = timers, t2 = timers->next; t2 != NULL; + t2prev = t2, t2 = t2->next ) { + if (iperf_time_compare(&t->time, &t2->time) < 0) { + /* Found it. */ + t2prev->next = t; + t->prev = t2prev; + t->next = t2; + t2->prev = t; + return; + } + } + /* Oops, got to the end of the list. Add to tail. */ + t2prev->next = t; + t->prev = t2prev; + t->next = NULL; + } + } +} + + +static void +list_remove( Timer* t ) +{ + if ( t->prev == NULL ) + timers = t->next; + else + t->prev->next = t->next; + if ( t->next != NULL ) + t->next->prev = t->prev; +} + + +static void +list_resort( Timer* t ) +{ + /* Remove the timer from the list. */ + list_remove( t ); + /* And add it back in, sorted correctly. */ + list_add( t ); +} + + +Timer* +tmr_create( + struct iperf_time* nowP, TimerProc* timer_proc, TimerClientData client_data, + int64_t usecs, int periodic ) +{ + struct iperf_time now; + Timer* t; + + getnow( nowP, &now ); + + if ( free_timers != NULL ) { + t = free_timers; + free_timers = t->next; + } else { + t = (Timer*) malloc( sizeof(Timer) ); + if ( t == NULL ) + return NULL; + } + + t->timer_proc = timer_proc; + t->client_data = client_data; + t->usecs = usecs; + t->periodic = periodic; + t->time = now; + iperf_time_add_usecs(&t->time, usecs); + /* Add the new timer to the active list. */ + list_add( t ); + + return t; +} + + +struct timeval* +tmr_timeout( struct iperf_time* nowP ) +{ + struct iperf_time now, diff; + int64_t usecs; + int past; + static struct timeval timeout; + + getnow( nowP, &now ); + /* Since the list is sorted, we only need to look at the first timer. */ + if ( timers == NULL ) + return NULL; + past = iperf_time_diff(&timers->time, &now, &diff); + if (past) + usecs = 0; + else + usecs = iperf_time_in_usecs(&diff); + timeout.tv_sec = usecs / 1000000LL; + timeout.tv_usec = usecs % 1000000LL; + return &timeout; +} + + +void +tmr_run( struct iperf_time* nowP ) +{ + struct iperf_time now; + Timer* t; + Timer* next; + + getnow( nowP, &now ); + for ( t = timers; t != NULL; t = next ) { + next = t->next; + /* Since the list is sorted, as soon as we find a timer + ** that isn't ready yet, we are done. + */ + if (iperf_time_compare(&t->time, &now) > 0) + break; + (t->timer_proc)( t->client_data, &now ); + if ( t->periodic ) { + /* Reschedule. */ + iperf_time_add_usecs(&t->time, t->usecs); + list_resort( t ); + } else + tmr_cancel( t ); + } +} + + +void +tmr_reset( struct iperf_time* nowP, Timer* t ) +{ + struct iperf_time now; + + getnow( nowP, &now ); + t->time = now; + iperf_time_add_usecs( &t->time, t->usecs ); + list_resort( t ); +} + + +void +tmr_cancel( Timer* t ) +{ + /* Remove it from the active list. */ + list_remove( t ); + /* And put it on the free list. */ + t->next = free_timers; + free_timers = t; + t->prev = NULL; +} + + +void +tmr_cleanup( void ) +{ + Timer* t; + + while ( free_timers != NULL ) { + t = free_timers; + free_timers = t->next; + free( (void*) t ); + } +} + + +void +tmr_destroy( void ) +{ + while ( timers != NULL ) + tmr_cancel( timers ); + tmr_cleanup(); +} |