void vlc_enable_override (void);
-#if defined (__GNUC__) /* typeof and statement-expression */ \
+#if defined (__GNUC__) \
&& (defined (__ELF__) && !defined (__sun__))
/* Solaris crashes on printf("%s", NULL); which is legal, but annoying. */
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
#include <dlfcn.h>
#include <pthread.h>
#ifdef HAVE_EXECINFO_H
}
#define LOG(level, ...) logbug(level, __func__, __VA_ARGS__)
+/* Evil non-standard GNU C macro ;)
+ * typeof keyword,
+ * statement-expression,
+ * nested function...
+ */
#define CALL(func, ...) \
- ({ typeof (func) *sym = getsym ( # func); sym (__VA_ARGS__); })
+({ \
+ static typeof (func) *sym = NULL; \
+ static pthread_once_t once = PTHREAD_ONCE_INIT; \
+ auto void getsym_once (void); \
+ void getsym_once (void) \
+ { \
+ sym = getsym ( # func); \
+ } \
+ pthread_once (&once, getsym_once); \
+ sym (__VA_ARGS__); \
+})
/*** Environment ***
* preserve reproducibility of the number sequence (which usually does not
* matter).
**/
-static pthread_mutex_t prng_lock = PTHREAD_MUTEX_INITIALIZER;
+static struct
+{
+ pthread_mutex_t lock;
+ unsigned int seed;
+} prng = { PTHREAD_MUTEX_INITIALIZER, 0, };
void srand (unsigned int seed)
{
- pthread_mutex_lock (&prng_lock);
+ pthread_mutex_lock (&prng.lock);
LOG("Warning", "%d", seed);
- CALL(srand, seed);
- pthread_mutex_unlock (&prng_lock);
+ prng.seed = seed;
+ pthread_mutex_unlock (&prng.lock);
}
int rand (void)
{
int ret;
- pthread_mutex_lock (&prng_lock);
+ pthread_mutex_lock (&prng.lock);
LOG("Warning", "");
- ret = CALL(rand);
- pthread_mutex_unlock (&prng_lock);
+ ret = rand_r (&prng.seed);
+ pthread_mutex_unlock (&prng.lock);
return ret;
}
/** Signals **/
#include <signal.h>
+static bool blocked_signal (int num)
+{
+ switch (num)
+ {
+ case SIGINT:
+ case SIGHUP:
+ case SIGQUIT:
+ case SIGTERM:
+ case SIGPIPE:
+ case SIGCHLD:
+ return true;
+ }
+ return false;
+}
+
void (*signal (int signum, void (*handler) (int))) (int)
{
if (override)
{
- const char *msg = "Error";
-
- if ((signum == SIGPIPE && handler == SIG_IGN)
- || (signum != SIGPIPE && handler == SIG_DFL))
- /* Same settings we already use */
- msg = "Warning";
- LOG(msg, "%d, %p", signum, handler);
+ if (handler != SIG_IGN && handler != SIG_DFL)
+ goto error;
+ if (!blocked_signal (signum))
+ goto error;
+ /* For our blocked signals, the handler won't matter much... */
+ if (handler == SIG_DFL)
+ LOG("Warning", "%d, SIG_DFL", signum, handler);
}
return CALL(signal, signum, handler);
+error:
+ LOG("Blocked", "%d, %p", signum, handler);
+ return SIG_DFL;
}
int sigaction (int signum, const struct sigaction *act, struct sigaction *old)
{
- if (act != NULL)
- LOG("Error", "%d, %p, %p", signum, act, old);
+ if (override && act != NULL)
+ {
+ if ((act->sa_flags & SA_SIGINFO)
+ || (act->sa_handler != SIG_IGN && act->sa_handler != SIG_DFL))
+ goto error;
+ if (act->sa_handler == SIG_DFL)
+ LOG("Warning", "%d, %p, SIG_DFL", signum, act);
+ }
return CALL(sigaction, signum, act, old);
+error:
+ LOG("Blocked", "%d, %p, %p", signum, act, old);
+ return -1;
}
}
+/* strerror() is not thread-safe in theory (POSIX), nor in practice (glibc).
+ * This caused quite nasty crashes in the history of VLC/Linux. */
+char *strerror (int val)
+{
+ if (override)
+ {
+ static const char msg[] =
+ "Error message unavailable (use strerror_r instead of strerror)!";
+ LOG("Blocked", "%d", val);
+ return (char *)msg;
+ }
+ return CALL(strerror, val);
+}
+
/*** Xlib ****/
#ifdef HAVE_X11_XLIB_H
# include <X11/Xlib.h>