added some missing checks for file being open before reading/writing

svn-id: r8043

1 files changed, 9 insertions, 0 deletions

diff --git a/common/file.cpp b/common/file.cpp
index 788b2b57cb..0b9dbbef68 100644
--- a/common/file.cpp
+++ b/common/file.cpp
@@ -230,6 +230,11 @@ uint32 File::read(void *ptr, uint32 len) {
 byte File::readByte() {
 	byte b;
 
+	if (_handle == NULL) {
+		error("File is not open!");
+		return 0;
+	}
+
 	if (fread(&b, 1, 1, _handle) != 1) {
 		clearerr(_handle);
 		_ioFailed = true;
@@ -293,6 +298,10 @@ uint32 File::write(void *ptr, uint32 len) {
 void File::writeByte(byte value) {
 	value ^= _encbyte;
 
+	if (_handle == NULL) {
+		error("File is not open!");
+	}
+
 	if (fwrite(&value, 1, 1, _handle) != 1) {
 		clearerr(_handle);
 		_ioFailed = true;