java-stack.h (GetAccessControlStack): Change return type.

2006-08-10  Gary Benson  <gbenson@redhat.com>

	* include/java-stack.h (GetAccessControlStack): Change return
	type.
	* stacktrace.cc (accesscontrol_trace_fn): Record the number of
	Java frames encountered.
	(GetAccessControlStack): Return a flag indicating whether a call to
	doPrivileged was encountered rather than an array of method names.
	* java/security/natVMAccessController.cc (getStack): Change return
	type.
	* java/security/VMAccessController.java (getStack): Likewise.
	(getContext): Change to reflect the above.

From-SVN: r116058

libjava/ChangeLog

+2006-08-10  Gary Benson  <gbenson@redhat.com>
+
+	* include/java-stack.h (GetAccessControlStack): Change return
+	type.
+	* stacktrace.cc (accesscontrol_trace_fn): Record the number of
+	Java frames encountered.
+	(GetAccessControlStack): Return a flag indicating whether a call to
+	doPrivileged was encountered rather than an array of method names.
+	* java/security/natVMAccessController.cc (getStack): Change return
+	type.
+	* java/security/VMAccessController.java (getStack): Likewise.
+	(getContext): Change to reflect the above.
+
 2006-08-09  Gary Benson  <gbenson@redhat.com>
 
 	* stacktrace.cc (accesscontrol_trace_fn): Skip non-Java frames.

libjava/include/java-stack.h

@@ -125,7 +125,7 @@ public:
   static void GetCallerInfo (jclass checkClass, jclass *, _Jv_Method **);
   static JArray<jclass> *GetClassContext (jclass checkClass);
   static ClassLoader *GetFirstNonSystemClassLoader (void);
-  static JArray<jobjectArray> *GetAccessControlStack ();
+  static jobjectArray GetAccessControlStack ();
   
 };
 

libjava/java/security/VMAccessController.java

@@ -178,9 +178,9 @@ final class VMAccessController
 
     inGetContext.set(Boolean.TRUE);
 
-    Object[][] stack = getStack();
+    Object[] stack = getStack();
     Class[] classes = (Class[]) stack[0];
-    String[] methods = (String[]) stack[1];
+    boolean privileged = ((Boolean) stack[1]).booleanValue();
 
     if (DEBUG)
       debug("got trace of length " + classes.length);
@@ -188,32 +188,24 @@ final class VMAccessController
     HashSet domains = new HashSet();
     HashSet seenDomains = new HashSet();
     AccessControlContext context = null;
-    int privileged = 0;
 
     // We walk down the stack, adding each ProtectionDomain for each
     // class in the call stack. If we reach a call to doPrivileged,
     // we don't add any more stack frames. We skip the first three stack
     // frames, since they comprise the calls to getStack, getContext,
     // and AccessController.getContext.
-    for (int i = 3; i < classes.length && privileged < 2; i++)
+    for (int i = 3; i < classes.length; i++)
       {
         Class clazz = classes[i];
-        String method = methods[i];
 
         if (DEBUG)
           {
-            debug("checking " + clazz + "." + method);
+            debug("checking " + clazz);
             // subject to getClassLoader RuntimePermission
             debug("loader = " + clazz.getClassLoader());
           }
 
-        // If the previous frame was a call to doPrivileged, then this is
-        // the last frame we look at.
-        if (privileged == 1)
-          privileged = 2;
-
-        if (clazz.equals (AccessController.class)
-            && method.equals ("doPrivileged"))
+        if (privileged && i == classes.length - 2)
           {
             // If there was a call to doPrivileged with a supplied context,
             // return that context. If using JAAS doAs*, it should be 
@@ -221,7 +213,6 @@ final class VMAccessController
             LinkedList l = (LinkedList) contexts.get();
             if (l != null)
               context = (AccessControlContext) l.getFirst();
-            privileged = 1;
           }
 
         // subject to getProtectionDomain RuntimePermission
@@ -270,16 +261,14 @@ final class VMAccessController
   }
 
   /**
-   * Returns a snapshot of the current call stack as a pair of arrays:
-   * the first an array of classes in the call stack, the second an array
-   * of strings containing the method names in the call stack. The two
-   * arrays match up, meaning that method <i>i</i> is declared in class
-   * <i>i</i>. The arrays are clean; it will only contain Java methods,
-   * and no element of the list should be null.
+   * Returns a snapshot of the current call stack as a two-element
+   * array. The first element is an array of classes in the call
+   * stack, and the second element is a boolean value indicating
+   * whether the trace stopped early because a call to doPrivileged
+   * was encountered.  If this boolean value is true then the call to
+   * doPrivileged will be the second-last frame in the returned trace.
    *
-   * @return A pair of arrays describing the current call stack. The first
-   *    element is an array of Class objects, and the second is an array
-   *    of Strings comprising the method names.
+   * @return A snapshot of the current call stack.
    */
-  private static native Object[][] getStack();
+  private static native Object[] getStack();
 }

libjava/java/security/natVMAccessController.cc

@@ -16,7 +16,7 @@ details.  */
 
 #include <java/security/VMAccessController.h>
 
-JArray<jobjectArray> *
+jobjectArray
 java::security::VMAccessController::getStack ()
 {
   return _Jv_StackTrace::GetAccessControlStack ();

libjava/stacktrace.cc

@@ -18,6 +18,7 @@ details.  */
 
 #include <stdio.h>
 
+#include <java/lang/Boolean.h>
 #include <java/lang/Class.h>
 #include <java/lang/Long.h>
 #include <java/security/AccessController.h>
@@ -536,59 +537,58 @@ _Jv_StackTrace::GetFirstNonSystemClassLoader ()
   return NULL;
 }
 
+struct AccessControlTraceData
+{
+  jint length;
+  jboolean privileged;
+};
+
 _Unwind_Reason_Code
 _Jv_StackTrace::accesscontrol_trace_fn (_Jv_UnwindState *state)
 {
+  AccessControlTraceData *trace_data = (AccessControlTraceData *)
+    state->trace_data;
   _Jv_StackFrame *frame = &state->frames[state->pos];
   FillInFrameInfo (frame);
 
   if (!(frame->klass && frame->meth))
     return _URC_NO_REASON;
 
-  bool *stopping = (bool *) state->trace_data;
-  if (*stopping)
+  trace_data->length++;
+
+  // If the previous frame was a call to doPrivileged, then this is
+  // the last frame we look at.
+  if (trace_data->privileged)
     return _URC_NORMAL_STOP;
   
   if (frame->klass == &::java::security::AccessController::class$
       && strcmp (frame->meth->name->chars(), "doPrivileged") == 0)
-    *stopping = true;
+    trace_data->privileged = true;
 
   return _URC_NO_REASON;
 }
 
-JArray<jobjectArray> *
+jobjectArray
 _Jv_StackTrace::GetAccessControlStack (void)
 {
   int trace_size = 100;
   _Jv_StackFrame frames[trace_size];
   _Jv_UnwindState state (trace_size);
   state.frames = (_Jv_StackFrame *) &frames;
+
+  AccessControlTraceData trace_data;
+  trace_data.length = 0;
+  trace_data.privileged = false;
+  
   state.trace_function = accesscontrol_trace_fn;
-  bool stopping = false;
-  state.trace_data = (void *) &stopping;
+  state.trace_data = (void *) &trace_data;
 
   UpdateNCodeMap();
   _Unwind_Backtrace (UnwindTraceFn, &state);
-  
-  jint length = 0;
 
-  for (int i = 0; i < state.pos; i++)
-    {
-      _Jv_StackFrame *frame = &state.frames[i];
-
-      if (frame->klass && frame->meth)
-	length++;
-    }
-
-  jclass array_class = _Jv_GetArrayClass (&::java::lang::Object::class$, NULL);
-  JArray<jobjectArray> *result =
-    (JArray<jobjectArray> *) _Jv_NewObjectArray (2, array_class, NULL);
   JArray<jclass> *classes = (JArray<jclass> *)
-    _Jv_NewObjectArray (length, &::java::lang::Class::class$, NULL);
-  JArray<jstring> *methods = (JArray<jstring> *)
-    _Jv_NewObjectArray (length, &::java::lang::String::class$, NULL);
-  jclass  *c = elements (classes);
-  jstring *m = elements (methods);
+    _Jv_NewObjectArray (trace_data.length, &::java::lang::Class::class$, NULL);
+  jclass *c = elements (classes);
 
   for (int i = 0, j = 0; i < state.pos; i++)
     {
@@ -596,13 +596,15 @@ _Jv_StackTrace::GetAccessControlStack (void)
       if (!frame->klass || !frame->meth)
 	continue;
       c[j] = frame->klass;
-      m[j] = JvNewStringUTF (frame->meth->name->chars());
       j++;
     }
 
-  jobjectArray *elems = elements (result);
-  elems[0] = (jobjectArray) classes;
-  elems[1] = (jobjectArray) methods;
-
+  jobjectArray result =
+    (jobjectArray) _Jv_NewObjectArray (2, &::java::lang::Object::class$,
+					 NULL);
+  jobject *r = elements (result);
+  r[0] = (jobject) classes;
+  r[1] = (jobject) new Boolean (trace_data.privileged);
+  
   return result;
 }