PERFORCE change 151913 for review

[Peter Wemm]

http://perforce.freebsd.org/chv.cgi?CH=151913

Change 151913 by peter at peter_cheese on 2008/10/25 19:28:57

	Make the sysctl wrapper work a little closer to reality.
	oldlenp is always written to if non null.  This is used to
	query ideal buffer sizes.

Affected files ...

.. //depot/projects/valgrind/coregrind/m_syswrap/syswrap-freebsd.c#17 edit

Differences ...

==== //depot/projects/valgrind/coregrind/m_syswrap/syswrap-freebsd.c#17 (text+ko) ====

@@ -872,16 +872,20 @@
    PRE_MEM_READ("sysctl(name)", ARG1, ARG2 * sizeof(int *));
    if (ARG5 != (UWord)NULL)
       PRE_MEM_READ("sysctl(new)", (Addr)ARG5, ARG6);
-   if (ARG3 != (UWord)NULL) {
-      PRE_MEM_READ("sysctl(oldlenp)", (Addr)ARG4, sizeof(vki_size_t));
-      PRE_MEM_WRITE("sysctl(oldval)", (Addr)ARG3, *(vki_size_t *)ARG4);
+   if (ARG4 != (UWord)NULL) {
+      if (ARG3 != (UWord)NULL) {
+         PRE_MEM_READ("sysctl(oldlenp)", (Addr)ARG4, sizeof(vki_size_t));
+         PRE_MEM_WRITE("sysctl(oldval)", (Addr)ARG3, *(vki_size_t *)ARG4);
+      }
+      PRE_MEM_WRITE("sysctl(oldlenp)", (Addr)ARG4, sizeof(vki_size_t));
    }
 }
 POST(sys___sysctl)
 {
-   if (ARG3 != (UWord)NULL) {
+   if (ARG4 != (UWord)NULL) {
       POST_MEM_WRITE((Addr)ARG4, sizeof(vki_size_t));
-      POST_MEM_WRITE((Addr)ARG3, *(vki_size_t *)ARG4);
+      if (ARG3 != (UWord)NULL)
+         POST_MEM_WRITE((Addr)ARG3, *(vki_size_t *)ARG4);
    }
 }