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#include <stdio.h>
#include <sys/stat.h>
#include <sys/resource.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdlib.h>
/*
* adjust_priority
*
* sets realtime priority
*/
#include "config.h"
#ifdef HAVE_REALTIME_SCHED
#include <sched.h>
void adjust_priority()
{
int sched = sched_getscheduler(0);
if(sched == SCHED_FIFO || sched == SCHED_RR)
{
printf(">> since the scheduling policy is not standard, I assume\n");
printf(" it has been adjusted to fit the needs of realtime audio\n");
}
else
{
struct sched_param sp;
long priority = (sched_get_priority_max(SCHED_FIFO) +
sched_get_priority_min(SCHED_FIFO))/2;
sp.sched_priority = priority;
if(sched_setscheduler(0, SCHED_FIFO, &sp) != -1)
{
printf(">> running as realtime process now (priority %ld)\n",
priority);
putenv("STARTED_THROUGH_ARTSWRAPPER=1");
}
else
{
/* can't set realtime priority */
putenv("STARTED_THROUGH_ARTSWRAPPER=2");
}
}
}
#else
void adjust_priority()
{
int prio;
prio = getpriority(PRIO_PROCESS,getpid());
if(prio > -10)
{
setpriority(PRIO_PROCESS,getpid(),-17);
prio = getpriority(PRIO_PROCESS,getpid());
}
/* no system support for realtime priority */
putenv("STARTED_THROUGH_ARTSWRAPPER=3");
if(prio > -10) {
printf(">> synthesizer priority is %d (which is unacceptable,",prio);
printf(" try running as root)\n");
}
else {
printf(">> synthesizer priority is %d (which is the best\n",prio);
printf(" we can get out of a non realtime system)\n");
}
}
#endif
int main(int argc, char **argv)
{
if(argc == 2)
{
if(strcmp(argv[1],"check") == 0)
{
/* backward compatibility with old artswrapper */
printf("okay\n");
return 0;
}
}
adjust_priority();
/* drop root privileges if running setuid root
(due to realtime priority stuff) */
if (geteuid() != getuid())
{
#if defined (HAVE_SETEUID) && !defined (HAVE_SETEUID_FAKE)
seteuid(getuid());
#else
setreuid(-1, getuid());
#endif
if (geteuid() != getuid()) {
perror("setuid()");
return 2;
}
}
if(argc == 0)
return 1;
/*
* Real-time status is passed to artsd via the environment variable
* STARTED_THROUGH_ARTSWRAPPER. It has one of the following values:
*
* unset - not running as real-time
* 1 - running as real-time
* 2 - no privileges to set real-time scheduling
* 3 - no support for real-time scheduling
*/
argv[0] = EXECUTE;
execv(EXECUTE,argv);
perror(EXECUTE);
return 1;
}
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