/* Tests for POSIX timer implementation using process CPU clock. */ #include <unistd.h> #if _POSIX_THREADS && defined _POSIX_CPUTIME #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <time.h> #include <pthread.h> #define TEST_CLOCK CLOCK_PROCESS_CPUTIME_ID #define TEST_CLOCK_MISSING(clock) \ (setup_test () ? "process CPU clock timer support" : NULL) /* This function is intended to rack up both user and system time. */ static void * chew_cpu (void *arg) { while (1) { static volatile char buf[4096]; for (int i = 0; i < 100; ++i) for (size_t j = 0; j < sizeof buf; ++j) buf[j] = 0xaa; int nullfd = open ("/dev/null", O_WRONLY); for (int i = 0; i < 100; ++i) for (size_t j = 0; j < sizeof buf; ++j) buf[j] = 0xbb; write (nullfd, (char *) buf, sizeof buf); close (nullfd); } return NULL; } static int setup_test (void) { /* Test timers on our own process CPU clock by having a worker thread eating CPU. First make sure we can make such timers at all. */ timer_t t; if (timer_create (TEST_CLOCK, NULL, &t) != 0) { printf ("timer_create: %m\n"); return 1; } timer_delete (t); pthread_t th; int e = pthread_create (&th, NULL, chew_cpu, NULL); if (e != 0) { printf ("pthread_create: %s\n", strerror (e)); exit (1); } return 0; } #else # define TEST_CLOCK_MISSING(clock) "process clocks" #endif #include "tst-timer4.c"