SDL: Copy result of SDL_iconv_string()

1 files changed, 28 insertions, 4 deletions

diff --git a/backends/platform/sdl/sdl.cpp b/backends/platform/sdl/sdl.cpp
index c89a560976..39933cc94c 100644
--- a/backends/platform/sdl/sdl.cpp
+++ b/backends/platform/sdl/sdl.cpp
@@ -28,6 +28,7 @@
 #include "common/taskbar.h"
 #include "common/textconsole.h"
 #include "common/translation.h"
+#include "common/encoding.h"
 
 #include "backends/saves/default/default-saves.h"
 
@@ -772,19 +773,42 @@ char *OSystem_SDL::convertEncoding(const char *to, const char *from, const char
 	int zeroBytes = 1;
 	if (Common::String(from).hasPrefixIgnoreCase("utf-16"))
 		zeroBytes = 2;
-	if (Common::String(from).hasPrefixIgnoreCase("utf-32"))
+	else if (Common::String(from).hasPrefixIgnoreCase("utf-32"))
 		zeroBytes = 4;
 
+	char *result;
 	// SDL_iconv_string() takes char * instead of const char * as it's third parameter
 	// with some older versions of SDL.
 #if SDL_VERSION_ATLEAST(2, 0, 0)
-	return SDL_iconv_string(to, from, string, length + zeroBytes);
+	result = SDL_iconv_string(to, from, string, length + zeroBytes);
 #else
 	char *stringCopy = (char *) calloc(sizeof(char), length + zeroBytes);
 	memcpy(stringCopy, string, length);
-	char *result = SDL_iconv_string(to, from, stringCopy, length + zeroBytes);
+	result = SDL_iconv_string(to, from, stringCopy, length + zeroBytes);
 	free(stringCopy);
-	return result;
 #endif
+	if (result == nullptr)
+		return nullptr;
+
+	// We need to copy the result, so that we can use SDL_free()
+	// on the string returned by SDL_iconv_string() and free()
+	// can then be used on the copyed and returned string.
+	// Sometimes free() and SDL_free() aren't compatible and
+	// using free() instead of SDL_free() can cause crashes.
+	size_t newLength = Common::Encoding::stringLength(result, to);
+	zeroBytes = 1;
+	if (Common::String(to).hasPrefixIgnoreCase("utf-16"))
+		zeroBytes = 2;
+	else if (Common::String(to).hasPrefixIgnoreCase("utf-32"))
+		zeroBytes = 4;
+	char *finalResult = (char *) malloc(newLength + zeroBytes);
+	if (!finalResult) {
+		warning("Could not allocate memory for encoding conversion");
+		SDL_free(result);
+		return nullptr;
+	}
+	memcpy(finalResult, result, newLength + zeroBytes);
+	SDL_free(result);
+	return finalResult;
 }