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#include "cctk.h"
#include "cctk_WarnLevel.h"
#include "cctk_Arguments.h"
#include "cctk_Parameters.h"
/* manpage of getpriority:
Including <sys/time.h> is not required these days,
but increases portability.
*/
#include <sys/time.h>
#include <errno.h>
#include <sys/resource.h>
void Nice_Renice(CCTK_ARGUMENTS)
{
/* do not declare the arguments, it will cause an error */
DECLARE_CCTK_PARAMETERS
int old_nice, new_nice, nice_return_value;
/* reset error variable */
errno=0;
/* save the old nice value */
old_nice=getpriority(PRIO_PROCESS, 0);
/* check errno */
if (errno)
{
switch (errno)
{
case ESRCH : /* this should never occur, since the 0 in getpriority
means this process, which should be found
*/
CCTK_INFO("getpriority received ESTCH-error.");
break;
case EINVAL : /* this should definitly not occur */
CCTK_INFO("getpriority received EINVAL-error.");
break;
case EPERM : /* this should never occur
It means, that the user of process did not match the
callers user */
CCTK_INFO("getpriority received EPERM-error.");
break;
case EACCES : /* This cannot occur: non root user attemted to lower
priority (since we did not call setpriority here */
CCTK_INFO("getpriority received EACCES-error.");
break;
default: /* This should not occur, otherwise it is an
undocumented errno */
CCTK_VInfo(CCTK_THORNSTRING,
"getpriority got undocumented errno %d",
errno);
}
CCTK_WARN(0, "This should never occur.");
/* in case CCTK_WARN did not stop the code */
CCTK_Abort(cctkGH, 1);
}
errno=0;
/* try to set the new priority */
nice_return_value=setpriority(PRIO_PROCESS, 0, Nice_nice);
/* check return value */
if (nice_return_value!=0)
{
switch (errno)
{
case ESRCH : /* this should never occur, since the 0 in setpriority
means this process, which should be found
*/
CCTK_INFO("setpriority received ESTCH-error.");
CCTK_WARN(0, "This should never occur.");
break;
case EINVAL : /* this should definitly not occur */
CCTK_INFO("setpriority received EINVAL-error.");
CCTK_WARN(0, "This should never occur.");
break;
case EPERM : /* this should never occur
It means, that the user of process did not match the
callers user */
CCTK_INFO("setpriority received EPERM-error.");
CCTK_WARN(0, "This should never occur.");
break;
case EACCES : /* This can occur: non root user attemted to lower
priority
*/
CCTK_WARN(0, "Only root can lower priorities.");
break;
default: /* This should not occur, otherwise it is an
undocumented errno */
CCTK_VInfo(CCTK_THORNSTRING,
"setpriority got undocumented errno %d",
errno);
}
/* in case CCTK_WARN did not stop the code */
CCTK_Abort(cctkGH, 1);
}
errno=0;
/* It should ok, but check the new priority */
new_nice=getpriority(PRIO_PROCESS, 0);
/* check errno */
if (errno)
{
switch (errno)
{
case ESRCH : /* this should never occur, since the 0 in getpriority
means this process, which should be found */
CCTK_INFO("getpriority received ESTCH-error.");
break;
case EINVAL : /* this should definitly not occur */
CCTK_INFO("getpriority received EINVAL-error.");
break;
case EPERM : /* this should never occur
It means, that the user of process did not match the
callers user */
CCTK_INFO("getpriority received EPERM-error.");
break;
case EACCES : /* This cannot occur: non root user attemted to lower
priority (since we did not call setpriority here
*/
CCTK_INFO("getpriority received EACCES-error.");
break;
default: /* This should not occur, otherwise it is an
undocumented errno */
CCTK_VInfo(CCTK_THORNSTRING,
"getpriority got undocumented errno %d",
errno);
}
CCTK_WARN(0, "This should never occur.");
/* in case CCTK_WARN did not stop the code */
CCTK_Abort(cctkGH, 1);
}
if (new_nice == Nice_nice)
{
CCTK_VInfo(CCTK_THORNSTRING,"Process reniced from nice level %d to %d.",
old_nice, new_nice);
}
else
{
/* this should never occur because of the error handling before */
CCTK_VInfo(CCTK_THORNSTRING,
"Process reniced to nice level %d instead of %d.",
new_nice, Nice_nice);
}
}
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