apple2: Add WOZ format [O. Galibert]

src/devices/bus/a2bus/a2diskiing.cpp

@@ -36,7 +36,7 @@ ROM_START( diskiing )
 ROM_END
 
 FLOPPY_FORMATS_MEMBER( a2bus_diskiing_device::floppy_formats )
-	FLOPPY_A216S_FORMAT, FLOPPY_RWTS18_FORMAT, FLOPPY_EDD_FORMAT
+	FLOPPY_A216S_FORMAT, FLOPPY_RWTS18_FORMAT, FLOPPY_EDD_FORMAT, FLOPPY_WOZ_FORMAT
 FLOPPY_FORMATS_END
 
 //-------------------------------------------------

src/lib/formats/ap2_dsk.cpp

@@ -1547,7 +1547,7 @@ const char *a2_edd_format::extensions() const
 
 bool a2_edd_format::supports_save() const
 {
-	return true;
+	return false;
 }
 
 int a2_edd_format::identify(io_generic *io, uint32_t form_factor)
@@ -1645,3 +1645,124 @@ bool a2_edd_format::load(io_generic *io, uint32_t form_factor, floppy_image *ima
 }
 
 const floppy_format_type FLOPPY_EDD_FORMAT = &floppy_image_format_creator<a2_edd_format>;
+
+
+a2_woz_format::a2_woz_format() : floppy_image_format_t()
+{
+}
+
+const char *a2_woz_format::name() const
+{
+	return "a2_woz";
+}
+
+const char *a2_woz_format::description() const
+{
+	return "Apple II WOZ Image";
+}
+
+const char *a2_woz_format::extensions() const
+{
+	return "woz";
+}
+
+bool a2_woz_format::supports_save() const
+{
+	return false;
+}
+
+const uint8_t a2_woz_format::signature[8] = { 0x57, 0x4f, 0x5a, 0x31, 0xff, 0x0a, 0x0d, 0x0a };
+
+int a2_woz_format::identify(io_generic *io, uint32_t form_factor)
+{
+	uint8_t header[8];
+	io_generic_read(io, header, 0, 8);
+	return !memcmp(header, signature, 8) ? 100 : 0;
+}
+
+bool a2_woz_format::load(io_generic *io, uint32_t form_factor, floppy_image *image)
+{
+	std::vector<uint8_t> img(io_generic_size(io));
+	io_generic_read(io, &img[0], 0, img.size());
+
+	// Check signature
+	if(memcmp(&img[0], signature, 8))
+		return false;
+
+	// Check integrity
+	uint32_t crc = crc32r(&img[12], img.size() - 12);
+	if(crc != r32(img, 8))
+		return false;
+
+	uint32_t off_info = find_tag(img, 0x4f464e49);
+	uint32_t off_tmap = find_tag(img, 0x50414d54);
+	uint32_t off_trks = find_tag(img, 0x534b5254);
+
+	if(!off_info || !off_tmap || !off_trks)
+		return false;
+	if(r8(img, off_info + 0) != 1)
+		return false;
+
+	bool is_35 = r8(img, off_info + 1) == 2;
+	if((form_factor == floppy_image::FF_35 && !is_35) || (form_factor == floppy_image::FF_525 && is_35))
+		return false;
+
+	unsigned int limit = is_35 ? 160 : 141;
+	for(unsigned int trkid = 0; trkid != limit; trkid++) {
+		int head = is_35 && trkid >= 80 ? 1 : 0;
+		int track = is_35 ? trkid % 80 : trkid / 4;
+		int subtrack = is_35 ? 0 : trkid & 3;
+
+		uint8_t idx = r8(img, off_tmap + trkid);
+		if(idx != 0xff) {
+			uint32_t boff = off_trks + 6656*idx;
+			generate_track_from_bitstream(track, head, &img[boff], r16(img, boff + 6648), image, subtrack, r16(img, boff + 6650));
+		}
+	}
+
+	return true;
+}
+
+uint32_t a2_woz_format::find_tag(const std::vector<uint8_t> &data, uint32_t tag)
+{
+	uint32_t offset = 12;
+	do {
+		if(r32(data, offset) == tag)
+			return offset + 8;
+		offset += r32(data, offset+4) + 8;
+	} while(offset < data.size() - 8);
+	return 0;
+}
+
+uint32_t a2_woz_format::r32(const std::vector<uint8_t> &data, uint32_t offset)
+{
+	return data[offset] | (data[offset+1] << 8) | (data[offset+2] << 16) | (data[offset+3] << 24);
+}
+
+uint16_t a2_woz_format::r16(const std::vector<uint8_t> &data, uint32_t offset)
+{
+	return data[offset] | (data[offset+1] << 8);
+}
+
+uint8_t a2_woz_format::r8(const std::vector<uint8_t> &data, uint32_t offset)
+{
+	return data[offset];
+}
+
+uint32_t a2_woz_format::crc32r(const uint8_t *data, uint32_t size)
+{
+	// Reversed crc32
+	uint32_t crc = 0xffffffff;
+	for(uint32_t i=0; i != size; i++) {
+		crc = crc ^ data[i];
+		for(int j=0; j<8; j++)
+			if(crc & 1)
+				crc = (crc >> 1) ^ 0xedb88320;
+			else
+				crc = crc >> 1;
+	}
+	return ~crc;
+}
+
+
+const floppy_format_type FLOPPY_WOZ_FORMAT = &floppy_image_format_creator<a2_woz_format>;

src/lib/formats/ap2_dsk.h

@@ -102,4 +102,29 @@ private:
 
 extern const floppy_format_type FLOPPY_EDD_FORMAT;
 
+class a2_woz_format : public floppy_image_format_t
+{
+public:
+		a2_woz_format();
+
+		virtual int identify(io_generic *io, uint32_t form_factor) override;
+		virtual bool load(io_generic *io, uint32_t form_factor, floppy_image *image) override;
+		virtual bool supports_save() const override;
+
+		virtual const char *name() const override;
+		virtual const char *description() const override;
+		virtual const char *extensions() const override;
+
+private:
+		static const uint8_t signature[8];
+
+		static uint32_t r32(const std::vector<uint8_t> &data, uint32_t offset);
+		static uint16_t r16(const std::vector<uint8_t> &data, uint32_t offset);
+		static uint8_t r8(const std::vector<uint8_t> &data, uint32_t offset);
+		static uint32_t crc32r(const uint8_t *data, uint32_t size);
+		static uint32_t find_tag(const std::vector<uint8_t> &data, uint32_t tag);
+};
+
+extern const floppy_format_type FLOPPY_WOZ_FORMAT;
+
 #endif /* AP2_DISK_H */

src/lib/formats/flopimg.cpp

@@ -1679,16 +1679,24 @@ void floppy_image_format_t::normalize_times(std::vector<uint32_t> &buffer)
 	}
 }
 
-void floppy_image_format_t::generate_track_from_bitstream(int track, int head, const uint8_t *trackbuf, int track_size, floppy_image *image, int subtrack)
+void floppy_image_format_t::generate_track_from_bitstream(int track, int head, const uint8_t *trackbuf, int track_size, floppy_image *image, int subtrack, int splice)
 {
-	// Maximal number of cells which happens when the buffer is all 1
+	if(splice >= track_size)
+		splice = 0;
+
 	std::vector<uint32_t> &dest = image->get_buffer(track, head, subtrack);
 	dest.clear();
 
+	int inversions = 0;
+	for(int i=0; i != track_size; i++)
+		if(trackbuf[i >> 3] & (0x80 >> (i & 7)))
+			inversions++;
+	int invert_splice = inversions & 1 ? splice : -1;
+
 	uint32_t cbit = floppy_image::MG_A;
 	uint32_t count = 0;
 	for(int i=0; i != track_size; i++)
-		if(trackbuf[i >> 3] & (0x80 >> (i & 7))) {
+		if((i == invert_splice) ^ !!(trackbuf[i >> 3] & (0x80 >> (i & 7)))) {
 			dest.push_back(cbit | (count+1));
 			cbit = cbit == floppy_image::MG_A ? floppy_image::MG_B : floppy_image::MG_A;
 			count = 1;
@@ -1699,7 +1707,8 @@ void floppy_image_format_t::generate_track_from_bitstream(int track, int head, c
 		dest.push_back(cbit | count);
 
 	normalize_times(dest);
-	image->set_write_splice_position(track, head, 0, subtrack);
+	int splpos = uint64_t(200000000) * splice / track_size;
+	image->set_write_splice_position(track, head, splpos, subtrack);
 }
 
 void floppy_image_format_t::generate_track_from_levels(int track, int head, std::vector<uint32_t> &trackbuf, int splice_pos, floppy_image *image)

src/lib/formats/flopimg.h

@@ -386,8 +386,10 @@ protected:
 	    @param trackbuf track input buffer.
 	    @param track_size in cells, not bytes.
 	    @param image
+		@param subtrack subtrack index, 0-3
+		@param splice write splice position
 	*/
-	void generate_track_from_bitstream(int track, int head, const uint8_t *trackbuf, int track_size, floppy_image *image, int subtrack = 0);
+	void generate_track_from_bitstream(int track, int head, const uint8_t *trackbuf, int track_size, floppy_image *image, int subtrack = 0, int splice = 0);
 
 	//! @brief Generate a track from cell level values (0/1/W/D/N).
 

src/mame/drivers/apple3.cpp

@@ -48,7 +48,7 @@ static SLOT_INTERFACE_START( a3_floppies )
 SLOT_INTERFACE_END
 
 FLOPPY_FORMATS_MEMBER( apple3_state::floppy_formats )
-	FLOPPY_A216S_FORMAT, FLOPPY_RWTS18_FORMAT, FLOPPY_EDD_FORMAT
+	FLOPPY_A216S_FORMAT, FLOPPY_RWTS18_FORMAT, FLOPPY_EDD_FORMAT, FLOPPY_WOZ_FORMAT
 FLOPPY_FORMATS_END
 
 MACHINE_CONFIG_START(apple3_state::apple3)

src/tools/floptool.cpp

@@ -76,6 +76,7 @@ static floppy_format_type floppy_formats[] = {
 	FLOPPY_A216S_FORMAT,
 	FLOPPY_RWTS18_FORMAT,
 	FLOPPY_EDD_FORMAT,
+	FLOPPY_WOZ_FORMAT,
 
 	FLOPPY_ATOM_FORMAT,
 	FLOPPY_ACORN_SSD_FORMAT,