[5/8] webservices: Protect writers with a critical section.

[Sebastian Lackner]

On 08.03.2017 11:25, Hans Leidekker wrote:
> +    if ((hr = write_set_element_namespace( writer )) != S_OK) goto done;
> +    if ((hr = write_startelement( writer )) != S_OK) goto done;
> +    if ((hr = write_endstartelement( writer )) != S_OK) goto done;
>      writer->state = WRITER_STATE_ENDSTARTELEMENT;
> +
> +done:
> +    LeaveCriticalSection( &writer->cs );
>      return S_OK;

You should return hr here.

>      for (i = offset; i < count; i++)
>      {
>          const char *ptr = (const char *)array + (offset + i) * type_size;
> -        if ((hr = write_element_node( writer, NULL, localname, ns )) != S_OK) return hr;
> +        if ((hr = write_element_node( writer, NULL, localname, ns )) != S_OK) goto done;
>          if ((hr = write_type( writer, WS_ELEMENT_TYPE_MAPPING, type, NULL, WS_WRITE_REQUIRED_POINTER,
> -                              &ptr, sizeof(ptr) )) != S_OK) return hr;
> -        if ((hr = write_endelement_node( writer )) != S_OK) return hr;
> +                              &ptr, sizeof(ptr) )) != S_OK) goto done;
> +        if ((hr = write_endelement_node( writer )) != S_OK) goto done;
>      }
>  
> -    return S_OK;
> +done:
> +    LeaveCriticalSection( &writer->cs );
> +    return hr;

It looks like hr will be undefined here if count == 0

>  }
>  
>  /**************************************************************************
> @@ -2392,9 +2662,20 @@ HRESULT WINAPI WsWriteXmlBuffer( WS_XML_WRITER *handle, WS_XML_BUFFER *buffer, W
>  
>      if (!writer || !xmlbuf) return E_INVALIDARG;
>  
> -    if ((hr = write_flush( writer )) != S_OK) return hr;
> -    if ((hr = write_grow_buffer( writer, xmlbuf->size )) != S_OK) return hr;
> +    EnterCriticalSection( &writer->cs );
> +
> +    if (writer->magic != WRITER_MAGIC)
> +    {
> +        LeaveCriticalSection( &writer->cs );
> +        return E_INVALIDARG;
> +    }
> +
> +    if ((hr = write_flush( writer )) != S_OK) goto done;
> +    if ((hr = write_grow_buffer( writer, xmlbuf->size )) != S_OK) goto done;
>      write_bytes( writer, xmlbuf->ptr, xmlbuf->size );
> +
> +done:
> +    LeaveCriticalSection( &writer->cs );
>      return S_OK;

Here you should also use hr.