SDL: Improve debug and warning messages when saving screenshots

In particular this adds a warning when failing to save a screenshot
in OpenGL mode (there was already one in SurfaceSDL mode).

2 files changed, 8 insertions, 3 deletions

diff --git a/backends/graphics/opengl/opengl-graphics.cpp b/backends/graphics/opengl/opengl-graphics.cpp
index 7b41699e80..b239802a0f 100644
--- a/backends/graphics/opengl/opengl-graphics.cpp
+++ b/backends/graphics/opengl/opengl-graphics.cpp
@@ -1302,7 +1302,7 @@ const Graphics::Font *OpenGLGraphicsManager::getFontOSD() {
 }
 #endif
 
-void OpenGLGraphicsManager::saveScreenshot(const Common::String &filename) const {
+bool OpenGLGraphicsManager::saveScreenshot(const Common::String &filename) const {
 	const uint width  = _outputScreenWidth;
 	const uint height = _outputScreenHeight;
 
@@ -1332,7 +1332,10 @@ void OpenGLGraphicsManager::saveScreenshot(const Common::String &filename) const
 
 	// Open file
 	Common::DumpFile out;
-	out.open(filename);
+	if (!out.open(filename)) {
+		delete[] pixels;
+		return false;
+	}
 
 	// Write BMP header
 	out.writeByte('B');
@@ -1357,6 +1360,7 @@ void OpenGLGraphicsManager::saveScreenshot(const Common::String &filename) const
 
 	// Free allocated memory
 	delete[] pixels;
+	return true;
 }
 
 } // End of namespace OpenGL
diff --git a/backends/graphics/opengl/opengl-graphics.h b/backends/graphics/opengl/opengl-graphics.h
index d3f8d792ba..f5f4cab305 100644
--- a/backends/graphics/opengl/opengl-graphics.h
+++ b/backends/graphics/opengl/opengl-graphics.h
@@ -296,8 +296,9 @@ protected:
 	 * uses Common::DumpFile for writing the screenshot.
 	 *
 	 * @param filename The output filename.
+	 * @return true on success, false otherwise
 	 */
-	void saveScreenshot(const Common::String &filename) const;
+	bool saveScreenshot(const Common::String &filename) const;
 
 private:
 	//