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/*
* This file is subject to the terms of the GFX License. If a copy of
* the license was not distributed with this file, you can obtain one at:
*
* http://ugfx.io/license.html
*/
// We need to include stdio.h below. Turn off GFILE_NEED_STDIO just for this file to prevent conflicts
#define GFILE_NEED_STDIO_MUST_BE_OFF
#include "../../gfx.h"
#if GFX_USE_OS_LINUX
// Linux seems to have deprecated pthread_yield() and now says to use sched_yield()
#define USE_SCHED_NOT_PTHREAD_YIELD GFXON
#include <stdio.h>
#include <unistd.h>
#include <time.h>
#if USE_SCHED_NOT_PTHREAD_YIELD
#include <sched.h>
#define linuxyield() sched_yield()
#else
#define linuxyield() pthread_yield()
#endif
static gfxMutex SystemMutex;
void _gosInit(void)
{
/* No initialization of the operating system itself is needed */
gfxMutexInit(&SystemMutex);
}
void _gosPostInit(void)
{
}
void _gosDeinit(void)
{
/* ToDo */
}
void gfxSystemLock(void) {
gfxMutexEnter(&SystemMutex);
}
void gfxSystemUnlock(void) {
gfxMutexExit(&SystemMutex);
}
void gfxYield(void) {
linuxyield();
}
void gfxHalt(const char *msg) {
if (msg)
fprintf(stderr, "%s\n", msg);
exit(1);
}
void gfxSleepMilliseconds(gDelay ms) {
struct timespec ts;
switch(ms) {
case gDelayNone:
linuxyield();
return;
case gDelayForever:
while(1)
sleep(60);
return;
default:
ts.tv_sec = ms / 1000;
ts.tv_nsec = (ms % 1000) * 1000000;
nanosleep(&ts, 0);
return;
}
}
void gfxSleepMicroseconds(gDelay us) {
struct timespec ts;
switch(us) {
case gDelayNone:
linuxyield();
return;
case gDelayForever:
while(1)
sleep(60);
return;
default:
ts.tv_sec = us / 1000000;
ts.tv_nsec = (us % 1000000) * 1000;
nanosleep(&ts, 0);
return;
}
}
gTicks gfxSystemTicks(void) {
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
}
gThread gfxThreadCreate(void *stackarea, size_t stacksz, gThreadpriority prio, DECLARE_THREAD_FUNCTION((*fn),p), void *param) {
gThread th;
(void) stackarea;
(void) stacksz;
(void) prio;
// Implementing priority with pthreads is a rats nest that is also pthreads implementation dependent.
// Only some pthreads schedulers support it, some implementations use the operating system process priority mechanisms.
// Even those that do support it can have different ranges of priority and "normal" priority is an undefined concept.
// Across different UNIX style operating systems things can be very different (let alone OS's such as Windows).
// Even just Linux changes the way priority works with different kernel schedulers and across kernel versions.
// For these reasons we ignore the priority.
if (pthread_create(&th, 0, fn, param))
return 0;
return th;
}
gThreadreturn gfxThreadWait(gThread thread) {
gThreadreturn retval;
if (pthread_join(thread, &retval))
return 0;
return retval;
}
#if GFX_USE_POSIX_SEMAPHORES
void gfxSemInit(gfxSem *pSem, gSemcount val, gSemcount limit) {
pSem->max = limit;
sem_init(&pSem->sem, 0, val);
}
void gfxSemDestroy(gfxSem *pSem) {
sem_destroy(&pSem->sem);
}
gBool gfxSemWait(gfxSem *pSem, gDelay ms) {
switch (ms) {
case gDelayForever:
return sem_wait(&pSem->sem) ? gFalse : gTrue;
case gDelayNone:
return sem_trywait(&pSem->sem) ? gFalse : gTrue;
default:
{
struct timespec tm;
clock_gettime(CLOCK_REALTIME, &tm);
tm.tv_sec += ms / 1000;
tm.tv_nsec += (ms % 1000) * 1000000;
return sem_timedwait(&pSem->sem, &tm) ? gFalse : gTrue;
}
}
}
void gfxSemSignal(gfxSem *pSem) {
int res;
res = 0;
sem_getvalue(&pSem->sem, &res);
if (res < pSem->max)
sem_post(&pSem->sem);
}
#else
void gfxSemInit(gfxSem *pSem, gSemcount val, gSemcount limit) {
pthread_mutex_init(&pSem->mtx, 0);
pthread_cond_init(&pSem->cond, 0);
pthread_mutex_lock(&pSem->mtx);
pSem->cnt = val;
pSem->max = limit;
pthread_mutex_unlock(&pSem->mtx);
}
void gfxSemDestroy(gfxSem *pSem) {
pthread_mutex_destroy(&pSem->mtx);
pthread_cond_destroy(&pSem->cond);
}
gBool gfxSemWait(gfxSem *pSem, gDelay ms) {
pthread_mutex_lock(&pSem->mtx);
switch (ms) {
case gDelayForever:
while (!pSem->cnt)
pthread_cond_wait(&pSem->cond, &pSem->mtx);
break;
case gDelayNone:
if (!pSem->cnt) {
pthread_mutex_unlock(&pSem->mtx);
return gFalse;
}
break;
default:
{
struct timespec tm;
clock_gettime(CLOCK_REALTIME, &tm);
tm.tv_sec += ms / 1000;
tm.tv_nsec += (ms % 1000) * 1000000;
while (!pSem->cnt) {
// We used to test the return value for ETIMEDOUT. This doesn't
// work in some current pthread libraries which return -1 instead
// and set errno to ETIMEDOUT. So, we will return gFalse on any error
// including a ETIMEDOUT.
if (pthread_cond_timedwait(&pSem->cond, &pSem->mtx, &tm)) {
pthread_mutex_unlock(&pSem->mtx);
return gFalse;
}
}
}
break;
}
pSem->cnt--;
pthread_mutex_unlock(&pSem->mtx);
return gTrue;
}
void gfxSemSignal(gfxSem *pSem) {
pthread_mutex_lock(&pSem->mtx);
if (pSem->cnt < pSem->max) {
pSem->cnt++;
pthread_cond_signal(&pSem->cond);
}
pthread_mutex_unlock(&pSem->mtx);
}
#endif // GFX_USE_POSIX_SEMAPHORES
#endif /* GFX_USE_OS_LINUX */
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