Changeset 4105 in vbox for trunk/src/VBox/Additions/common/VBoxGuestLib

Timestamp:

Aug 10, 2007 9:13:38 AM (17 years ago)

Author:

vboxsync

Message:

Use alloca instead of wasting 1k/2k of kernel stack.

File:

• trunk/src/VBox/Additions/common/VBoxGuestLib/HGCMInternal.cpp (modified) (4 diffs)

trunk/src/VBox/Additions/common/VBoxGuestLib/HGCMInternal.cpp

@@ -24 +24 @@
 #include <iprt/string.h>
 #include <iprt/assert.h>
+#include <iprt/alloca.h>
 
 /* These functions can be only used by VBoxGuest. */
@@ -128 +129 @@
 
     if (!pCallInfo || !pAsyncCallback || pCallInfo->cParms > VBOX_HGCM_MAX_PARMS)
+    {
+        AssertFailed();
         return VERR_INVALID_PARAMETER;
+    }
 
     dprintf (("VbglHGCMCall: pCallInfo->cParms = %d, pHGCMCall->u32Function = %d\n", pCallInfo->cParms, pCallInfo->u32Function));
@@ -143 +147 @@
     if (VBOX_SUCCESS(rc))
     {
-        void *apvCtx[VBOX_HGCM_MAX_PARMS];
-        memset (apvCtx, 0, sizeof (apvCtx));
+        void **apvCtx = (void **)alloca(sizeof(void *) * pCallInfo->cParms);
+        memset (apvCtx, 0, sizeof(void *) * pCallInfo->cParms);
 
         /* Initialize request memory */
@@ -251 +255 @@
                 }
             }
+            else
+                Assert(!apvCtx[iParm]);
         }