| /* clock_getcpuclockid -- Get a clockid_t for process CPU time. Linux version. |
| Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <errno.h> |
| #include <time.h> |
| #include <unistd.h> |
| #include <kernel-features.h> |
| #include "kernel-posix-cpu-timers.h" |
| |
| #ifndef HAS_CPUCLOCK |
| # define HAS_CPUCLOCK 1 |
| #endif |
| |
| int |
| clock_getcpuclockid (pid_t pid, clockid_t *clock_id) |
| { |
| #ifdef __NR_clock_getres |
| /* The clockid_t value is a simple computation from the PID. |
| But we do a clock_getres call to validate it. */ |
| |
| const clockid_t pidclock = MAKE_PROCESS_CPUCLOCK (pid, CPUCLOCK_SCHED); |
| |
| # if !(__ASSUME_POSIX_CPU_TIMERS > 0) |
| extern int __libc_missing_posix_cpu_timers attribute_hidden; |
| # if !(__ASSUME_POSIX_TIMERS > 0) |
| extern int __libc_missing_posix_timers attribute_hidden; |
| if (__libc_missing_posix_timers && !__libc_missing_posix_cpu_timers) |
| __libc_missing_posix_cpu_timers = 1; |
| # endif |
| if (!__libc_missing_posix_cpu_timers) |
| # endif |
| { |
| INTERNAL_SYSCALL_DECL (err); |
| int r = INTERNAL_SYSCALL (clock_getres, err, 2, pidclock, NULL); |
| if (!INTERNAL_SYSCALL_ERROR_P (r, err)) |
| { |
| *clock_id = pidclock; |
| return 0; |
| } |
| |
| # if !(__ASSUME_POSIX_TIMERS > 0) |
| if (INTERNAL_SYSCALL_ERRNO (r, err) == ENOSYS) |
| { |
| /* The kernel doesn't support these calls at all. */ |
| __libc_missing_posix_timers = 1; |
| __libc_missing_posix_cpu_timers = 1; |
| } |
| else |
| # endif |
| if (INTERNAL_SYSCALL_ERRNO (r, err) == EINVAL) |
| { |
| # if !(__ASSUME_POSIX_CPU_TIMERS > 0) |
| if (pidclock == MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED) |
| || INTERNAL_SYSCALL_ERROR_P (INTERNAL_SYSCALL |
| (clock_getres, err, 2, |
| MAKE_PROCESS_CPUCLOCK |
| (0, CPUCLOCK_SCHED), NULL), |
| err)) |
| /* The kernel doesn't support these clocks at all. */ |
| __libc_missing_posix_cpu_timers = 1; |
| else |
| # endif |
| /* The clock_getres system call checked the PID for us. */ |
| return ESRCH; |
| } |
| else |
| return INTERNAL_SYSCALL_ERRNO (r, err); |
| } |
| #endif |
| |
| /* We don't allow any process ID but our own. */ |
| if (pid != 0 && pid != getpid ()) |
| return EPERM; |
| |
| #ifdef CLOCK_PROCESS_CPUTIME_ID |
| if (HAS_CPUCLOCK) |
| { |
| /* Store the number. */ |
| *clock_id = CLOCK_PROCESS_CPUTIME_ID; |
| |
| return 0; |
| } |
| #endif |
| |
| /* We don't have a timer for that. */ |
| return ENOENT; |
| } |