compiler-rt/test/lsan/TestCases/Linux/guard-page.c

   1 // Check that if LSan finds that SP doesn't point into thread stack (e.g.
   2 // if swapcontext is used), LSan will not hit the guard page.
   3 // RUN: %clang_lsan %s -o %t && %run %t
   4 // Missing 'getcontext' and 'makecontext' on Android.
   5 // UNSUPPORTED: android
   6
   7 #include <errno.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <pthread.h>
  12 #include <ucontext.h>
  13
  14 pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
  15 pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
  16 int ctxfunc_started = 0;
  17
  18 static void die(const char* msg, int err) {
  19   if (err == 0)
  20     err = errno;
  21   fprintf(stderr, "%s: %s\n", msg, strerror(err));
  22   exit(EXIT_FAILURE);
  23 }
  24
  25 static void ctxfunc() {
  26   pthread_mutex_lock(&mutex);
  27   ctxfunc_started = 1;
  28   // printf("ctxfunc\n");
  29   pthread_cond_signal(&cond);
  30   pthread_mutex_unlock(&mutex);
  31   // Leave this context alive when the program exits.
  32   for (;;);
  33 }
  34
  35 static void* thread(void* arg) {
  36   (void)arg;
  37   ucontext_t ctx;
  38   void* stack;
  39
  40   if (getcontext(&ctx) < 0)
  41     die("getcontext", 0);
  42   stack = malloc(1 << 12);
  43   if (stack == NULL)
  44     die("malloc", 0);
  45   ctx.uc_stack.ss_sp = stack;
  46   ctx.uc_stack.ss_size = 1 << 12;
  47   makecontext(&ctx, ctxfunc, 0);
  48   setcontext(&ctx);
  49   die("setcontext", 0);
  50   return NULL;
  51 }
  52
  53 int main() {
  54   pthread_t tid;
  55   int i;
  56
  57   pthread_mutex_lock(&mutex);
  58   i = pthread_create(&tid, NULL, thread, NULL);
  59   if (i != 0)
  60     die("pthread_create", i);
  61   while (!ctxfunc_started) pthread_cond_wait(&cond, &mutex);
  62   pthread_mutex_unlock(&mutex);
  63   return 0;
  64 }