Bug 699528. Make pausing/unpausing JSD try to turn off/on debug mode …

…as needed. r=sfink a=LegNeato

The new boolean argument to SetDebugModeWhenPossible is needed because if we allow sync-disable of debug mode we seem to crash when loading pages with Firebug active.

js/jsd/idl/jsdIDebuggerService.idl

@@ -274,7 +274,10 @@ interface jsdIDebuggerService : nsISupports
      */
     unsigned long pause();
     /**
-     * Undo a pause.
+     * Undo a pause.  Once this is called, the debugger won't start
+     * getting execution callbacks until the stack is fully unwound so
+     * that no JS scripts are live.  There is no way to query whether
+     * there are such scripts left to unwind at a given point in time.
      *
      * @return depth The number of remaining pending pause calls.
      */

js/jsd/jsd_xpc.cpp

@@ -471,7 +471,7 @@ jsds_NotifyPendingDeadScripts (JSContext *cx)
     if (jsds) {
         NS_ADDREF(jsds);
         jsds->GetScriptHook (getter_AddRefs(hook));
-        jsds->Pause(nsnull);
+        jsds->DoPause(nsnull, true);
     }
 
     DeadScript *deadScripts = gDeadScripts;
@@ -506,7 +506,7 @@ jsds_NotifyPendingDeadScripts (JSContext *cx)
     }
 
     if (jsds) {
-        jsds->UnPause(nsnull);
+        jsds->DoUnPause(nsnull, true);
         NS_RELEASE(jsds);
     }
 }
@@ -583,9 +583,9 @@ jsds_ErrorHookProc (JSDContext *jsdc, JSContext *cx, const char *message,
         errnum   = 0;
     }
 
-    gJsds->Pause(nsnull);
+    gJsds->DoPause(nsnull, true);
     hook->OnError (nsDependentCString(message), fileName, line, pos, flags, errnum, val, &rval);
-    gJsds->UnPause(nsnull);
+    gJsds->DoUnPause(nsnull, true);
 
     running = PR_FALSE;
     if (!rval)
@@ -626,9 +626,9 @@ jsds_CallHookProc (JSDContext* jsdc, JSDThreadState* jsdthreadstate,
     nsCOMPtr<jsdIStackFrame> frame =
         getter_AddRefs(jsdStackFrame::FromPtr(jsdc, jsdthreadstate,
                                               native_frame));
-    gJsds->Pause(nsnull);
+    gJsds->DoPause(nsnull, true);
     hook->OnCall(frame, type);    
-    gJsds->UnPause(nsnull);
+    gJsds->DoUnPause(nsnull, true);
     jsdStackFrame::InvalidateAll();
 
     return JS_TRUE;
@@ -688,13 +688,13 @@ jsds_ExecutionHookProc (JSDContext* jsdc, JSDThreadState* jsdthreadstate,
     nsCOMPtr<jsdIStackFrame> frame =
         getter_AddRefs(jsdStackFrame::FromPtr(jsdc, jsdthreadstate,
                                               native_frame));
-    gJsds->Pause(nsnull);
+    gJsds->DoPause(nsnull, true);
     jsdIValue *inout_rv = js_rv;
     NS_IF_ADDREF(inout_rv);
     hook->OnExecute (frame, type, &inout_rv, &hook_rv);
     js_rv = inout_rv;
     NS_IF_RELEASE(inout_rv);
-    gJsds->UnPause(nsnull);
+    gJsds->DoUnPause(nsnull, true);
     jsdStackFrame::InvalidateAll();
 
     if (hook_rv == JSD_HOOK_RETURN_RET_WITH_VAL ||
@@ -734,9 +734,9 @@ jsds_ScriptHookProc (JSDContext* jsdc, JSDScript* jsdscript, JSBool creating,
 #ifdef CAUTIOUS_SCRIPTHOOK
         JS_UNKEEP_ATOMS(rt);
 #endif
-        gJsds->Pause(nsnull);
+        gJsds->DoPause(nsnull, true);
         hook->OnScriptCreated (script);
-        gJsds->UnPause(nsnull);
+        gJsds->DoUnPause(nsnull, true);
 #ifdef CAUTIOUS_SCRIPTHOOK
         JS_KEEP_ATOMS(rt);
 #endif
@@ -763,9 +763,9 @@ jsds_ScriptHookProc (JSDContext* jsdc, JSDScript* jsdscript, JSBool creating,
             JS_UNKEEP_ATOMS(rt);
 #endif
 
-            gJsds->Pause(nsnull);
+            gJsds->DoPause(nsnull, true);
             hook->OnScriptDestroyed (jsdis);
-            gJsds->UnPause(nsnull);
+            gJsds->DoUnPause(nsnull, true);
 #ifdef CAUTIOUS_SCRIPTHOOK
             JS_KEEP_ATOMS(rt);
 #endif
@@ -2546,21 +2546,13 @@ jsdService::AsyncOn (jsdIActivationCallback *activationCallback)
 {
     nsresult  rv;
 
-    /* get JS things from the CallContext */
-    nsCOMPtr<nsIXPConnect> xpc = do_GetService(nsIXPConnect::GetCID(), &rv);
-    if (NS_FAILED(rv)) return rv;
-
-    nsAXPCNativeCallContext *cc = nsnull;
-    rv = xpc->GetCurrentNativeCallContext(&cc);
-    if (NS_FAILED(rv)) return rv;
-
-    JSContext *cx;
-    rv = cc->GetJSContext (&cx);
+    nsCOMPtr<nsIXPConnect_MOZILLA_10_BRANCH> xpc =
+        do_GetService(nsIXPConnect::GetCID(), &rv);
     if (NS_FAILED(rv)) return rv;
 
     mActivationCallback = activationCallback;
 
-    return xpc->SetDebugModeWhenPossible(PR_TRUE);
+    return xpc->SetDebugModeWhenPossible(PR_TRUE, PR_TRUE);
 }
 
 NS_IMETHODIMP
@@ -2702,11 +2694,12 @@ jsdService::Off (void)
 #endif
 
     nsresult rv;
-    nsCOMPtr<nsIXPConnect> xpc = do_GetService(nsIXPConnect::GetCID(), &rv);
+    nsCOMPtr<nsIXPConnect_MOZILLA_10_BRANCH> xpc =
+        do_GetService(nsIXPConnect::GetCID(), &rv);
     if (NS_FAILED(rv))
         return rv;
 
-    xpc->SetDebugModeWhenPossible(PR_FALSE);
+    xpc->SetDebugModeWhenPossible(PR_FALSE, PR_TRUE);
 
     return NS_OK;
 }
@@ -2721,6 +2714,12 @@ jsdService::GetPauseDepth(PRUint32 *_rval)
 
 NS_IMETHODIMP
 jsdService::Pause(PRUint32 *_rval)
+{
+    return DoPause(_rval, false);
+}
+
+nsresult
+jsdService::DoPause(PRUint32 *_rval, bool internalCall)
 {
     if (!mCx)
         return NS_ERROR_NOT_INITIALIZED;
@@ -2734,6 +2733,16 @@ jsdService::Pause(PRUint32 *_rval)
         JSD_ClearTopLevelHook (mCx);
         JSD_ClearFunctionHook (mCx);
         JSD_DebuggerPause (mCx);
+
+        nsresult rv;
+        nsCOMPtr<nsIXPConnect_MOZILLA_10_BRANCH> xpc =
+            do_GetService(nsIXPConnect::GetCID(), &rv);
+        if (NS_FAILED(rv)) return rv;
+
+        if (!internalCall) {
+            rv = xpc->SetDebugModeWhenPossible(PR_FALSE, PR_FALSE);
+            NS_ENSURE_SUCCESS(rv, rv);
+        }
     }
 
     if (_rval)
@@ -2744,6 +2753,12 @@ jsdService::Pause(PRUint32 *_rval)
 
 NS_IMETHODIMP
 jsdService::UnPause(PRUint32 *_rval)
+{
+    return DoUnPause(_rval, false);
+}
+
+nsresult
+jsdService::DoUnPause(PRUint32 *_rval, bool internalCall)
 {
     if (!mCx)
         return NS_ERROR_NOT_INITIALIZED;
@@ -2774,6 +2789,16 @@ jsdService::UnPause(PRUint32 *_rval)
             JSD_SetFunctionHook (mCx, jsds_CallHookProc, NULL);
         else
             JSD_ClearFunctionHook (mCx);
+
+        nsresult rv;
+        nsCOMPtr<nsIXPConnect_MOZILLA_10_BRANCH> xpc =
+            do_GetService(nsIXPConnect::GetCID(), &rv);
+        if (NS_FAILED(rv)) return rv;
+
+        if (!internalCall) {
+            rv = xpc->SetDebugModeWhenPossible(PR_TRUE, PR_FALSE);
+            NS_ENSURE_SUCCESS(rv, rv);
+        }
     }
 
     if (_rval)
@@ -3110,9 +3135,9 @@ jsdService::EnterNestedEventLoop (jsdINestCallback *callback, PRUint32 *_rval)
 
     if (NS_SUCCEEDED(stack->Push(nsnull))) {
         if (callback) {
-            Pause(nsnull);
+            DoPause(nsnull, true);
             rv = callback->OnNest();
-            UnPause(nsnull);
+            DoUnPause(nsnull, true);
         }
 
         while (NS_SUCCEEDED(rv) && mNestedLoopLevel >= nestLevel) {

js/jsd/jsd_xpc.h

@@ -291,6 +291,9 @@ class jsdService : public jsdIDebuggerService
 
     PRBool CheckInterruptHook() { return !!mInterruptHook; }
 
+    nsresult DoPause(PRUint32 *_rval, bool internalCall);
+    nsresult DoUnPause(PRUint32 *_rval, bool internalCall);
+
   private:
     PRBool      mOn;
     PRUint32    mPauseLevel;

js/src/xpconnect/idl/nsIXPConnect.idl

@@ -797,3 +797,12 @@ interface nsIXPConnect : nsISupports
      */
     [noscript] void setDebugModeWhenPossible(in boolean mode);
 };
+
+[uuid(44bf9047-914a-4f47-a1ec-e417927bacd1)]
+interface nsIXPConnect_MOZILLA_10_BRANCH : nsISupports
+{
+    // A 2-argument form of setDebugModeWhenPossible that allows
+    // controlling whether sync disable of debug mode is allowed.
+    [noscript] void setDebugModeWhenPossible(in boolean mode,
+                                             in boolean allowSyncDisable);
+};

js/src/xpconnect/src/nsXPConnect.cpp

@@ -67,14 +67,15 @@
 
 #include "xpcquickstubs.h"
 
-NS_IMPL_THREADSAFE_ISUPPORTS7(nsXPConnect,
+NS_IMPL_THREADSAFE_ISUPPORTS8(nsXPConnect,
                               nsIXPConnect,
                               nsISupportsWeakReference,
                               nsIThreadObserver,
                               nsIJSRuntimeService,
                               nsIJSContextStack,
                               nsIThreadJSContextStack,
-                              nsIJSEngineTelemetryStats)
+                              nsIJSEngineTelemetryStats,
+                              nsIXPConnect_MOZILLA_10_BRANCH)
 
 nsXPConnect* nsXPConnect::gSelf = nsnull;
 JSBool       nsXPConnect::gOnceAliveNowDead = JS_FALSE;
@@ -2884,9 +2885,15 @@ nsXPConnect::Base64Decode(JSContext *cx, jsval val, jsval *out)
 
 NS_IMETHODIMP
 nsXPConnect::SetDebugModeWhenPossible(PRBool mode)
+{
+    return SetDebugModeWhenPossible(mode, PR_FALSE);
+}
+
+NS_IMETHODIMP
+nsXPConnect::SetDebugModeWhenPossible(PRBool mode, PRBool allowSyncDisable)
 {
     gDesiredDebugMode = mode;
-    if (!mode)
+    if (!mode && allowSyncDisable)
         CheckForDebugMode(mRuntime->GetJSRuntime());
     return NS_OK;
 }

js/src/xpconnect/src/xpcprivate.h

@@ -462,7 +462,8 @@ class nsXPConnect : public nsIXPConnect,
                     public nsCycleCollectionParticipant,
                     public nsIJSRuntimeService,
                     public nsIThreadJSContextStack,
-                    public nsIJSEngineTelemetryStats
+                    public nsIJSEngineTelemetryStats,
+                    public nsIXPConnect_MOZILLA_10_BRANCH
 {
 public:
     // all the interface method declarations...
@@ -473,6 +474,7 @@ class nsXPConnect : public nsIXPConnect,
     NS_DECL_NSIJSCONTEXTSTACK
     NS_DECL_NSITHREADJSCONTEXTSTACK
     NS_DECL_NSIJSENGINETELEMETRYSTATS
+    NS_DECL_NSIXPCONNECT_MOZILLA_10_BRANCH
 
     // non-interface implementation
 public: