Properly use RAII to reduce complication

native/jni/utils/include/stream.h

@@ -18,7 +18,6 @@ public:
 	virtual int read(void *buf, size_t len);
 	virtual int write(const void *buf, size_t len);
 	virtual off_t seek(off_t off, int whence);
-	virtual int close();
 	virtual ~stream() = default;
 };
 
@@ -26,11 +25,10 @@ public:
 class filter_stream : public stream {
 public:
 	filter_stream(FILE *fp) : fp(fp) {}
-	~filter_stream() override { if (fp) close(); }
+	~filter_stream() override;
 
 	int read(void *buf, size_t len) override;
 	int write(const void *buf, size_t len) override;
-	int close() override;
 
 	void set_base(FILE *f);
 	template <class T, class... Args >

native/jni/utils/stream.cpp

@@ -19,9 +19,8 @@ static fpos_t strm_seek(void *v, fpos_t off, int whence) {
 
 static int strm_close(void *v) {
 	auto strm = reinterpret_cast<stream *>(v);
-	int ret = strm->close();
 	delete strm;
-	return ret;
+	return 0;
 }
 
 FILE *open_stream(stream *strm) {
@@ -46,8 +45,8 @@ off_t stream::seek(off_t off, int whence) {
 	return -1;
 }
 
-int stream::close() {
-	return 0;
+filter_stream::~filter_stream() {
+	if (fp) fclose(fp);
 }
 
 int filter_stream::read(void *buf, size_t len) {
@@ -58,12 +57,6 @@ int filter_stream::write(const void *buf, size_t len) {
 	return fwrite(buf, 1, len, fp);
 }
 
-int filter_stream::close() {
-	int ret = fclose(fp);
-	fp = nullptr;
-	return ret;
-}
-
 void filter_stream::set_base(FILE *f) {
 	if (fp) fclose(fp);
 	fp = f;