[compiler-rt] Fix the prototype of ioctl interceptor

The interceptor of ioctl is using a non-standard prototype:

  INTERCEPTOR(int, ioctl, int d, unsigned request, void *arg)

At least on OS X, the request argument should be unsigned long and not
just unsigned, and also instead of the last argument (arg), the function
should be accepting a variable number of arguments, so the prototype
should be:

  int ioctl(int fildes, unsigned long request, ...);

We can still keep using `unsigned` internally to save space, because we
know that all possible values of `request` will fit into it.

Reviewed at http://reviews.llvm.org/D7038

llvm-svn: 226926

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
index b22e8f1..c72b208 100644 (file)
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
@@ -1028,8 +1028,12 @@ FORMAT_INTERCEPTOR_IMPL(__isoc99_snprintf, __isoc99_vsnprintf, str, size,
 
 #if SANITIZER_INTERCEPT_IOCTL
 #include "sanitizer_common_interceptors_ioctl.inc"
-INTERCEPTOR(int, ioctl, int d, unsigned request, void *arg) {
+INTERCEPTOR(int, ioctl, int d, unsigned long request, ...) {
   void *ctx;
+  va_list ap;
+  va_start(ap, request);
+  void *arg = va_arg(ap, void *);
+  va_end(ap);
   COMMON_INTERCEPTOR_ENTER(ctx, ioctl, d, request, arg);
 
   CHECK(ioctl_initialized);
@@ -1038,6 +1042,10 @@ INTERCEPTOR(int, ioctl, int d, unsigned request, void *arg) {
   // This effectively disables ioctl handling in TSan.
   if (!common_flags()->handle_ioctl) return REAL(ioctl)(d, request, arg);
 
+  // Although request is unsigned long, the rest of the interceptor uses it
+  // as just "unsigned" to save space, because we know that all values fit in
+  // "unsigned" - they are compile-time constants.
+
   const ioctl_desc *desc = ioctl_lookup(request);
   ioctl_desc decoded_desc;
   if (!desc) {