Bug 1154435 - [nsDumpUtil] Refine nsDumpUtils::OpenTempFile to make this function more flexible. r=dhylands

- Add one more mode in this function (CREATE/CREATE_UNIQUE)
- export the header file for the usage of other components

xpcom/base/moz.build

@@ -53,6 +53,7 @@ EXPORTS += [
     'nscore.h',
     'nsCycleCollector.h',
     'nsDebugImpl.h',
+    'nsDumpUtils.h',
     'nsError.h',
     'nsGZFileWriter.h',
     'nsIID.h',

xpcom/base/nsDumpUtils.cpp

@@ -435,7 +435,7 @@ FifoWatcher::OnFileCanReadWithoutBlocking(int aFd)
 // Otherwise, it will open a file named aFilename under "NS_OS_TEMP_DIR".
 /* static */ nsresult
 nsDumpUtils::OpenTempFile(const nsACString& aFilename, nsIFile** aFile,
-                          const nsACString& aFoldername)
+                          const nsACString& aFoldername, Mode aMode)
 {
 #ifdef ANDROID
   // For Android, first try the downloads directory which is world-readable
@@ -488,9 +488,13 @@ nsDumpUtils::OpenTempFile(const nsACString& aFilename, nsIFile** aFile,
     return rv;
   }
 
-  rv = file->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0666);
-  if (NS_WARN_IF(NS_FAILED(rv))) {
-    return rv;
+  if (aMode == CREATE_UNIQUE) {
+    rv = file->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0666);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+  } else {
+    file->Create(nsIFile::NORMAL_FILE_TYPE, 0666);
   }
 
 #ifdef ANDROID

xpcom/base/nsDumpUtils.h

@@ -180,10 +180,15 @@ private:
 
 #endif // XP_UNIX }
 
-
 class nsDumpUtils
 {
 public:
+
+  enum Mode {
+    CREATE,
+    CREATE_UNIQUE
+  };
+
   /**
    * This function creates a new unique file based on |aFilename| in a
    * world-readable temp directory. This is the system temp directory
@@ -193,7 +198,8 @@ public:
    */
   static nsresult OpenTempFile(const nsACString& aFilename,
                                nsIFile** aFile,
-                               const nsACString& aFoldername = EmptyCString());
+                               const nsACString& aFoldername = EmptyCString(),
+                               Mode aMode = CREATE_UNIQUE);
 };
 
 #endif