#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
+#include <pthread.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/socket.h>
return retval;
}
-static unsigned int poweroftwo(unsigned int x)
-{
- unsigned int power2 = 1;
- unsigned int hardcoded = 2147483648u; /* FIX max 2^31 */
-
- if (x < 2)
- return 2;
-
- while (power2 < x && power2 < hardcoded)
- power2 *= 2;
+/* Return the power of two which is equal or higher to v */
- return power2;
+static unsigned int pow2_higher_or_eq(unsigned int v)
+{
+ int hb = fls(v);
+ int hbm1 = hb-1;
+ int retval = 1<<(hb-1);
+
+ if(v-retval == 0)
+ return retval;
+ else
+ return retval<<1;
}
static int do_cmd_set_subbuf_size(const char *recvbuf, struct ustcomm_source *src)
goto end;
}
- power = poweroftwo(size);
+ power = pow2_higher_or_eq(size);
+ power = max_t(unsigned int, 2u, power);
if (power != size)
- WARN("using the next 2^n = %u\n", power);
+ WARN("using the next power of two for buffer size = %u\n", power);
ltt_lock_traces();
trace = _ltt_trace_find_setup(trace_name);
void create_listener(void)
{
int result;
+ sigset_t sig_all_blocked;
+ sigset_t orig_parent_mask;
if(have_listener) {
WARN("not creating listener because we already had one");
return;
}
+ /* A new thread created by pthread_create inherits the signal mask
+ * from the parent. To avoid any signal being received by the
+ * listener thread, we block all signals temporarily in the parent,
+ * while we create the listener thread.
+ */
+
+ sigfillset(&sig_all_blocked);
+
+ result = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_parent_mask);
+ if(result) {
+ PERROR("pthread_sigmask: %s", strerror(result));
+ }
+
result = pthread_create(&listener_thread, NULL, listener_main, NULL);
if(result == -1) {
PERROR("pthread_create");
}
+ /* Restore original signal mask in parent */
+ result = pthread_sigmask(SIG_SETMASK, &orig_parent_mask, NULL);
+ if(result) {
+ PERROR("pthread_sigmask: %s", strerror(result));
+ }
+
have_listener = 1;
}