Fixing bug 243484. Adding 'count' out params to ToNewUTF8String() and UTF8ToNewUnicode() that tells the caller how many units (8 or 16 bit) that was returned. r=dbaron@dbaron.org, sr=darin@meer.net

xpcom/string/public/nsReadableUtils.h

@@ -126,10 +126,11 @@ NS_COM char* ToNewCString( const nsACString& aSource );
    * contains embedded nulls.
    *
    * @param aSource a UTF-16 string (made of PRUnichar's)
+   * @param aUTF8Count the number of 8-bit units that was returned
    * @return a new |char| buffer you must free with |nsMemory::Free|.
    */
 
-NS_COM char* ToNewUTF8String( const nsAString& aSource );
+NS_COM char* ToNewUTF8String( const nsAString& aSource, PRUint32 *aUTF8Count = nsnull );
 
 
   /**
@@ -171,10 +172,11 @@ NS_COM PRUnichar* ToNewUnicode( const nsACString& aSource );
    * may not help you if |aSource| contains embedded nulls.
    *
    * @param aSource an 8-bit wide string, UTF-8 encoded
+   * @param aUTF16Count the number of 16-bit units that was returned
    * @return a new |PRUnichar| buffer you must free with |nsMemory::Free|.
    *         (UTF-16 encoded)
    */
-NS_COM PRUnichar* UTF8ToNewUnicode( const nsACString& aSource );
+NS_COM PRUnichar* UTF8ToNewUnicode( const nsACString& aSource, PRUint32 *aUTF16Count = nsnull );
 
   /**
    * Copies |aLength| 16-bit code units from the start of |aSource| to the

xpcom/string/src/nsReadableUtils.cpp

@@ -325,13 +325,16 @@ ToNewCString( const nsAString& aSource )
 
 NS_COM
 char*
-ToNewUTF8String( const nsAString& aSource )
+ToNewUTF8String( const nsAString& aSource, PRUint32 *aUTF8Count )
   {
     nsAString::const_iterator start, end;
     CalculateUTF8Size calculator;
     copy_string(aSource.BeginReading(start), aSource.EndReading(end),
                 calculator);
 
+    if (aUTF8Count)
+      *aUTF8Count = calculator.Size();
+
     char *result = NS_STATIC_CAST(char*,
         nsMemory::Alloc(calculator.Size() + 1));
 
@@ -385,13 +388,16 @@ ToNewUnicode( const nsACString& aSource )
 
 NS_COM
 PRUnichar*
-UTF8ToNewUnicode( const nsACString& aSource )
+UTF8ToNewUnicode( const nsACString& aSource, PRUint32 *aUTF16Count )
   {
     nsACString::const_iterator start, end;
     CalculateUTF8Length calculator;
     copy_string(aSource.BeginReading(start), aSource.EndReading(end),
                 calculator);
 
+    if (aUTF16Count)
+      *aUTF16Count = calculator.Length();
+
     PRUnichar *result = NS_STATIC_CAST(PRUnichar*,
         nsMemory::Alloc(sizeof(PRUnichar) * (calculator.Length() + 1)));