VLC: infrastructure to detect and/or work-around thread-unsafe calls

bin/Makefile.am

@@ -14,7 +14,7 @@ AM_CFLAGS = `$(VLC_CONFIG) --cflags vlc`
 if !HAVE_WIN32
 if !HAVE_WINCE
 bin_PROGRAMS += vlc-wrapper
-vlc_SOURCES = vlc.c
+vlc_SOURCES = vlc.c override.c
 endif
 endif
 

bin/override.c

+/*****************************************************************************
+ * override.c: overriden function calls for VLC media player
+ *****************************************************************************
+ * Copyright (C) 2010 Rémi Denis-Courmont
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdbool.h>
+
+void vlc_enable_override (void);
+
+static bool override = false;
+
+void vlc_enable_override (void)
+{
+    override = true;
+}
+
+#if defined (__GNUC__) /* typeof and statement-expression */ \
+ && (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 <dlfcn.h>
+
+static void vlogbug (const char *level, const char *func, const char *fmt,
+                     va_list ap)
+{
+    flockfile (stderr);
+    fprintf (stderr, "%s: call to %s(", level, func);
+    vfprintf (stderr, fmt, ap);
+    fputs (")\n", stderr);
+    funlockfile (stderr);
+}
+
+static void logbug (const char *level, const char *func, const char *fmt, ...)
+{
+    va_list ap;
+
+    va_start (ap, fmt);
+    vlogbug (level, func, fmt, ap);
+    va_end (ap);
+}
+
+static void *getsym (const char *name)
+{
+    void *sym = dlsym (RTLD_NEXT, name);
+    if (sym == NULL)
+    {
+        fprintf (stderr, "Cannot resolve symbol %s!\n", name);
+        abort ();
+    }
+    return sym;
+}
+
+#define LOG(level, ...) logbug(level, __func__, __VA_ARGS__)
+#define CALL(func, ...) \
+    ({ typeof (func) *sym = getsym ( # func); sym (__VA_ARGS__); })
+
+
+#endif /* __ELF__ */

bin/vlc.c

@@ -42,6 +42,7 @@
 /* Explicit HACK */
 extern void LocaleFree (const char *);
 extern char *FromLocale (const char *);
+extern void vlc_enable_override (void);
 
 #include <signal.h>
 #include <time.h>
@@ -157,6 +158,8 @@ int main( int i_argc, const char *ppsz_argv[] )
             return 1; // BOOM!
     argv[argc] = NULL;
 
+    vlc_enable_override ();
+
     /* Initialize libvlc */
     libvlc_instance_t *vlc = libvlc_new (argc, argv);