[gdb/testsuite] Fix interrupted sleep in multi-threaded test-cases

When running test-case gdb.threads/continue-pending-status.exp with native, I
have:
...
(gdb) continue^M
Continuing.^M
PASS: gdb.threads/continue-pending-status.exp: attempt 0: continue for ctrl-c
^C^M
Thread 1 "continue-pendin" received signal SIGINT, Interrupt.^M
[Switching to Thread 0x7ffff7fc4740 (LWP 1276)]^M
0x00007ffff758e4c0 in __GI___nanosleep () at nanosleep.c:27^M
27        return SYSCALL_CANCEL (nanosleep, requested_time, remaining);^M
(gdb) PASS: gdb.threads/continue-pending-status.exp: attempt 0: caught interrupt
...
but with target board unix/-m32, I run into:
...
(gdb) continue^M
Continuing.^M
PASS: gdb.threads/continue-pending-status.exp: attempt 0: continue for ctrl-c
[Thread 0xf74aeb40 (LWP 31957) exited]^M
[Thread 0xf7cafb40 (LWP 31956) exited]^M
[Inferior 1 (process 31952) exited normally]^M
(gdb) Quit^M
...

The problem is that the sleep (300) call at the end of main is interrupted,
which causes the inferior to exit before the ctrl-c can be send.

This problem is described at "Interrupted System Calls" in the docs, and the
suggested solution (using a sleep loop) indeed fixes the problem.

Fix this instead using the more prevalent:
...
  alarm (300);
  ...
  while (1) sleep (1);
...
which is roughly equivalent because the sleep is called at the end of main,
but slightly better because it guards against hangs from the start rather than
from the end of main.

Likewise in gdb.base/watch_thread_num.exp.

Likewise in gdb.btrace/enable-running.exp, but use the sleep loop there,
because the sleep is not called at the end of main.

Tested on x86_64-linux.

diff --git a/gdb/testsuite/gdb.base/watch_thread_num.c b/gdb/testsuite/gdb.base/watch_thread_num.c
index 9a6f825b84415b8fca266caf4500b7b887b2af1e..46029cf1291628be95451fc00afdbb9cc6fe3191 100644 (file)
--- a/gdb/testsuite/gdb.base/watch_thread_num.c
+++ b/gdb/testsuite/gdb.base/watch_thread_num.c
@@ -43,6 +43,8 @@ int main () {
     void *thread_result;
     long i;
 
+    alarm (180);
+
     pthread_barrier_init (&threads_started_barrier, NULL, NUM + 1);
 
     pthread_barrier_init (&threads_started_barrier2, NULL, 2);
@@ -61,7 +63,10 @@ int main () {
 
     pthread_join (threads[0], NULL);
 
-    sleep (180);  /* first child thread exited */
+    /* first child thread exited */
+
+    while (1)
+      sleep (1);
 
     exit (EXIT_SUCCESS);
 }

diff --git a/gdb/testsuite/gdb.btrace/enable-running.c b/gdb/testsuite/gdb.btrace/enable-running.c
index 8f76241a892142c97491fa3a2d949192db47e154..2db3b7d28cb155efa7e9fa6a8a567a2d3bef2885 100644 (file)
--- a/gdb/testsuite/gdb.btrace/enable-running.c
+++ b/gdb/testsuite/gdb.btrace/enable-running.c
@@ -25,7 +25,9 @@ test (void *arg)
 {
   /* Let's hope this is long enough for GDB to enable tracing and check that
      everything is working as expected.  */
-  sleep (10);
+  int unslept = 10;
+  while (unslept > 0)
+    unslept = sleep (unslept);
 
   return arg;
 }

diff --git a/gdb/testsuite/gdb.threads/continue-pending-status.c b/gdb/testsuite/gdb.threads/continue-pending-status.c
index 53e5944a0a92cae22c06a4d503c0ed46331ec034..965a071fe329a03d0caf1c29da84ddf50ddd0b56 100644 (file)
--- a/gdb/testsuite/gdb.threads/continue-pending-status.c
+++ b/gdb/testsuite/gdb.threads/continue-pending-status.c
@@ -41,6 +41,8 @@ main (void)
 {
   int i;
 
+  alarm (300);
+
   pthread_barrier_init (&barrier, NULL, NUM_THREADS);
 
   for (i = 0; i < NUM_THREADS; i++)
@@ -53,6 +55,8 @@ main (void)
       assert (res == 0);
     }
 
-  sleep (300);
+  while (1)
+    sleep (1);
+
   return 0;
 }