gsdx: Fix GS dump readback EOF handling

An EOF only occurs after attempting to read past the end of the file.
Account for this correctly, which fixes a potential infinite loop when
reading back an xz compressed GS dump.

plugins/GSdx/GS.cpp

@@ -1603,11 +1603,9 @@ EXPORT_C GSReplay(char* lpszCmdLine, int renderer)
 
 		file->Read(regs, 0x2000);
 
-		while(!file->IsEof())
+		uint8 type;
+		while(file->Read(&type, 1))
 		{
-			uint8 type;
-			file->Read(&type, 1);
-
 			Packet* p = new Packet();
 
 			p->type = type;

plugins/GSdx/GSLzma.cpp

@@ -111,14 +111,14 @@ void GSDumpLzma::Decompress() {
 }
 
 bool GSDumpLzma::IsEof() {
-	return feof(m_fp) && (m_avail == 0);
+	return feof(m_fp) && m_avail == 0 && m_strm.avail_in == 0;
 }
 
-void GSDumpLzma::Read(void* ptr, size_t size) {
+bool GSDumpLzma::Read(void* ptr, size_t size) {
 	size_t off = 0;
 	uint8_t* dst = (uint8_t*)ptr;
 	size_t full_size = size;
-	while (size) {
+	while (size && !IsEof()) {
 		if (m_avail == 0) {
 			Decompress();
 		}
@@ -130,7 +130,13 @@ void GSDumpLzma::Read(void* ptr, size_t size) {
 		m_start += l;
 		off     += l;
 	}
-	Repack(ptr, full_size);
+
+	if (size == 0) {
+		Repack(ptr, full_size);
+		return true;
+	}
+
+	return false;
 }
 
 GSDumpLzma::~GSDumpLzma() {
@@ -156,17 +162,17 @@ bool GSDumpRaw::IsEof() {
 	return feof(m_fp);
 }
 
-void GSDumpRaw::Read(void* ptr, size_t size) {
-	if (size == 1) {
-		// I don't know why but read of size 1 is not happy
-		int v = fgetc(m_fp);
-		memcpy(ptr, &v, 1);
-	} else {
-		size_t ret = fread(ptr, 1, size, m_fp);
-		if (ret != size) {
-			fprintf(stderr, "GSDumpRaw:: Read error (%zu/%zu)\n", ret, size);
-			throw "BAD"; // Just exit the program
-		}
+bool GSDumpRaw::Read(void* ptr, size_t size) {
+	size_t ret = fread(ptr, 1, size, m_fp);
+	if (ret != size && ferror(m_fp)) {
+		fprintf(stderr, "GSDumpRaw:: Read error (%zu/%zu)\n", ret, size);
+		throw "BAD"; // Just exit the program
 	}
-	Repack(ptr, size);
+
+	if (ret == size) {
+		Repack(ptr, size);
+		return true;
+	}
+
+	return false;
 }

plugins/GSdx/GSLzma.h

@@ -30,7 +30,7 @@ class GSDumpFile {
 
 	public:
 	virtual bool IsEof() = 0;
-	virtual void Read(void* ptr, size_t size) = 0;
+	virtual bool Read(void* ptr, size_t size) = 0;
 
 	GSDumpFile(char* filename, const char* repack_filename);
 	virtual ~GSDumpFile();
@@ -54,8 +54,8 @@ class GSDumpLzma : public GSDumpFile {
 	GSDumpLzma(char* filename, const char* repack_filename);
 	virtual ~GSDumpLzma();
 
-	bool IsEof();
-	void Read(void* ptr, size_t size);
+	bool IsEof() final;
+	bool Read(void* ptr, size_t size) final;
 };
 
 class GSDumpRaw : public GSDumpFile {
@@ -67,13 +67,11 @@ class GSDumpRaw : public GSDumpFile {
 	size_t		m_avail;
 	size_t		m_start;
 
-	void Decompress();
-
 	public:
 
 	GSDumpRaw(char* filename, const char* repack_filename);
 	virtual ~GSDumpRaw() = default;
 
-	bool IsEof();
-	void Read(void* ptr, size_t size);
+	bool IsEof() final;
+	bool Read(void* ptr, size_t size) final;
 };