fix bug 108045. Don't crash on case where an xpt file is missing an interface info that was there when the manifest got built. Insead, fail gracefully and force the subsequent run to re-autoreg. r=jst sr=brendan

xpcom/reflect/xptinfo/src/xptiInterfaceInfoManager.cpp

@@ -418,6 +418,18 @@ xptiInterfaceInfoManager::LoadFile(const xptiTypelib& aTypelibRecord,
     {
 #ifdef XPTI_HAS_ZIP_SUPPORT
         zipItem = &aWorkingSet->GetZipItemAt(aTypelibRecord.GetZipItemIndex());
+        
+        // See the big comment below in the 'non-zip' case...
+        if(zipItem->GetGuts())
+        {
+            NS_ERROR("Trying to load an xpt file from a zip twice");    
+            
+            // Force an autoreg on next run
+            (void) xptiManifest::Delete(this);
+
+            return PR_FALSE;
+        }
+        
         LOG_LOAD(("# loading zip item %s::%s\n", fileRecord->GetName(), zipItem->GetName()));
         header = xptiZipLoader::ReadXPTFileFromZip(file, zipItem->GetName(), aWorkingSet);
 #else
@@ -426,6 +438,37 @@ xptiInterfaceInfoManager::LoadFile(const xptiTypelib& aTypelibRecord,
     } 
     else
     {
+        // The file would only have guts already if we previously failed to 
+        // find an interface info in a file where the manifest claimed it was 
+        // going to be. 
+        //
+        // Normally, when the file gets loaded (and the guts set) then all 
+        // interfaces would also be resolved. So, if we are here again for
+        // the same file then there must have been some interface that was 
+        // expected but not present. Now we are explicitly trying to find it
+        // and it isn't going to be there this time either.
+        //
+        // This is an assertion style error in a DEBUG build because it shows 
+        // that we failed to detect this in autoreg. For release builds (where
+        // autoreg is not run on every startup) it is just bad. But by returning
+        // PR_FALSE we mark this interface as RESOLVE_FAILED and get on with 
+        // things without crashing or anything.
+        //
+        // We don't want to do an autoreg here because this is too much of an 
+        // edge case (and in that odd case it might autoreg multiple times if
+        // many interfaces had been removed). But, by deleting the manifest we 
+        // force the system to get it right on the next run.
+        
+        if(fileRecord->GetGuts())
+        {
+            NS_ERROR("Trying to load an xpt file twice");    
+            
+            // Force an autoreg on next run
+            (void) xptiManifest::Delete(this);
+
+            return PR_FALSE;
+        }
+
         LOG_LOAD(("^ loading file %s\n", fileRecord->GetName()));
         header = ReadXPTFile(file, aWorkingSet);
     } 

xpcom/reflect/xptinfo/src/xptiManifest.cpp

@@ -728,6 +728,23 @@ PRBool xptiManifest::Read(xptiInterfaceInfoManager* aMgr,
     return succeeded;
 }        
 
+// static 
+PRBool xptiManifest::Delete(xptiInterfaceInfoManager* aMgr)
+{
+    nsCOMPtr<nsILocalFile> aFile;
+    if(!aMgr->GetCloneOfManifestDir(getter_AddRefs(aFile)) || !aFile)
+        return PR_FALSE;
+    
+    if(NS_FAILED(aFile->Append(g_MainManifestFilename)))
+        return PR_FALSE;
 
-     
+    PRBool exists;
+    if(NS_FAILED(aFile->Exists(&exists)))
+        return PR_FALSE;
+
+    if(exists && NS_FAILED(aFile->Remove(PR_FALSE)))
+        return PR_FALSE;
+    
+    return PR_TRUE;
+}
 

xpcom/reflect/xptinfo/src/xptiprivate.h

@@ -607,6 +607,8 @@ public:
     static PRBool Write(xptiInterfaceInfoManager* aMgr,
                         xptiWorkingSet*           aWorkingSet);
 
+    static PRBool Delete(xptiInterfaceInfoManager* aMgr);
+
     xptiManifest(); // no implementation
 };