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#ifndef _DEFAULT_SOURCE
#define _DEFAULT_SOURCE
#endif
#include <pthread.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/prctl.h>
#include <sys/psx_syscall.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>
typedef union tp {
long long unsigned raw;
pthread_t pt;
} thread_ptr;
static void say_hello_expecting(const char *title, int n, int kept) {
int keeper = prctl(PR_GET_KEEPCAPS);
thread_ptr tp;
tp.pt = pthread_self();
printf("hello [%d], %s<%d> %llx (keepcaps=%d vs. want=%d)\n",
getpid(), title, n, tp.raw, keeper, kept);
if (keeper != kept) {
printf("--> FAILURE %s thread=%llx has wrong keepcaps: got=%d want=%d\n",
title, tp.raw, keeper, kept);
exit(1);
}
}
pthread_mutex_t mu;
pthread_cond_t cond;
int global_kept = 0;
int step = 0;
int replies = 0;
int launched = 0;
int started = 0;
static void *say_hello(void *args) {
int count = 0;
pthread_mutex_lock(&mu);
started++;
int this_step = step+1;
pthread_cond_broadcast(&cond);
pthread_mutex_unlock(&mu);
pthread_mutex_lock(&mu);
do {
while (this_step > step) {
pthread_cond_wait(&cond, &mu);
}
say_hello_expecting("thread", count, global_kept);
replies++;
pthread_cond_broadcast(&cond);
pthread_mutex_unlock(&mu);
this_step++;
pthread_mutex_lock(&mu);
} while (++count != 3);
pthread_mutex_unlock(&mu);
return NULL;
}
int main(int argc, char **argv) {
pthread_t tid[3];
int i;
pid_t child = 0;
char * const stop_argv[3] = { argv[0], strdup("stop"), NULL };
if (argc != 1) {
printf("child %d starting\n", getpid());
usleep(2000);
printf("child %d exiting\n", getpid());
exit(0);
}
for (i = 0; i<10; i++) {
printf("iteration [%d]: %d\n", getpid(), i);
pthread_mutex_lock(&mu);
global_kept = !global_kept;
replies = 0;
step = i;
pthread_mutex_unlock(&mu);
psx_syscall(SYS_prctl, PR_SET_KEEPCAPS, global_kept);
pthread_mutex_lock(&mu);
step++;
pthread_cond_broadcast(&cond);
pthread_mutex_unlock(&mu);
say_hello_expecting("main", i, global_kept);
pthread_mutex_lock(&mu);
while (replies < launched) {
pthread_cond_wait(&cond, &mu);
}
pthread_mutex_unlock(&mu);
if (i < 3) {
if (!child) {
child = fork();
if (!child) {
usleep(2000);
execve(argv[0], stop_argv, NULL);
perror("failed to exec");
exit(1);
} else {
printf("pid=%d forked -> %d\n", getpid(), child);
}
}
launched++;
pthread_create(&tid[i], NULL, say_hello, NULL);
/* Confirm that the thread is started. */
pthread_mutex_lock(&mu);
while (started < launched) {
printf("[%d] started=%d vs %d\n", getpid(), started, launched);
pthread_cond_wait(&cond, &mu);
}
printf("[%d] started=%d vs %d\n", getpid(), started, launched);
pthread_cond_broadcast(&cond);
pthread_mutex_unlock(&mu);
} else if (i < 6) {
/* Confirm one thread has finished. */
pthread_join(tid[i-3], NULL);
launched--;
}
}
if (child) {
int status;
waitpid(child, &status, 0);
if (status) {
printf("child %d FAILED: %d\n", child, status);
exit(1);
}
}
printf("%s PASSED\n", argv[0]);
exit(0);
}
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