--- BasiliskII/src/disk.cpp	2001/07/01 14:38:02	1.10
+++ BasiliskII/src/disk.cpp	2005/07/24 14:05:16	1.17
@@ -1,7 +1,7 @@
 /*
  *  disk.cpp - Generic disk driver
  *
- *  Basilisk II (C) 1997-2001 Christian Bauer
+ *  Basilisk II (C) 1997-2005 Christian Bauer
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -26,6 +26,8 @@
  *    Technote FL 24: "Don't Look at ioPosOffset for Devices"
  */
 
+#include "sysdeps.h"
+
 #include <string.h>
 #include <vector>
 
@@ -33,7 +35,6 @@
 using std::vector;
 #endif
 
-#include "sysdeps.h"
 #include "cpu_emulation.h"
 #include "main.h"
 #include "macos_util.h"
@@ -71,13 +72,14 @@ const uint8 DiskIcon[258] = {
 
 // Struct for each drive
 struct disk_drive_info {
-	disk_drive_info() : num(0), fh(NULL), read_only(false), status(0) {}
+	disk_drive_info() : num(0), fh(NULL), start_byte(0), read_only(false), status(0) {}
 	disk_drive_info(void *fh_, bool ro) : num(0), fh(fh_), read_only(ro), status(0) {}
 
 	void close_fh(void) { Sys_close(fh); }
 
 	int num;			// Drive number
 	void *fh;			// File handle
+	loff_t start_byte;	// Start of HFS partition on disk
 	uint32 num_blocks;	// Size in 512-byte blocks
 	bool to_be_mounted;	// Flag: drive must be mounted in accRun
 	bool read_only;		// Flag: force write protection
@@ -111,6 +113,39 @@ static drive_vec::iterator get_drive_inf
 
 
 /*
+ *  Find HFS partition, set info->start_byte and info->num_blocks
+ *  (0 = no partition map or HFS partition found, assume flat disk image)
+ */
+
+static void find_hfs_partition(disk_drive_info &info)
+{
+	info.start_byte = 0;
+	info.num_blocks = 0;
+	uint8 *map = new uint8[512];
+
+	// Search first 64 blocks for HFS partition
+	for (int i=0; i<64; i++) {
+		if (Sys_read(info.fh, map, i * 512, 512) != 512)
+			break;
+
+		// Not a partition map block? Then look at next block
+		uint16 sig = (map[0] << 8) | map[1];
+		if (sig != 0x504d)
+			continue;
+
+		// Partition map block found, Apple HFS partition?
+		if (strcmp((char *)(map + 48), "Apple_HFS") == 0) {
+			info.start_byte = (loff_t)((map[8] << 24) | (map[9] << 16) | (map[10] << 8) | map[11]) << 9;
+			info.num_blocks = (map[12] << 24) | (map[13] << 16) | (map[14] << 8) | map[15];
+			D(bug(" HFS partition found at %d, %d blocks\n", info.start_byte, info.num_blocks));
+			break;
+		}
+	}
+	delete[] map;
+}
+
+
+/*
  *  Initialization
  */
 
@@ -163,7 +198,9 @@ bool DiskMountVolume(void *fh)
 			info->read_only = SysIsReadOnly(info->fh);
 			WriteMacInt8(info->status + dsDiskInPlace, 1);	// Inserted removable disk
 			WriteMacInt8(info->status + dsWriteProt, info->read_only ? 0xff : 0);
-			info->num_blocks = SysGetFileSize(info->fh) / 512;
+			find_hfs_partition(*info);
+			if (info->start_byte == 0)
+				info->num_blocks = SysGetFileSize(info->fh) / 512;
 			WriteMacInt16(info->status + dsDriveSize, info->num_blocks & 0xffff);
 			WriteMacInt16(info->status + dsDriveS1, info->num_blocks >> 16);
 			info->to_be_mounted = true;
@@ -249,7 +286,9 @@ int16 DiskOpen(uint32 pb, uint32 dce)
 			if (disk_in_place) {
 				D(bug(" disk inserted\n"));
 				WriteMacInt8(info->status + dsWriteProt, info->read_only ? 0x80 : 0);
-				info->num_blocks = SysGetFileSize(info->fh) / 512;
+				find_hfs_partition(*info);
+				if (info->start_byte == 0)
+					info->num_blocks = SysGetFileSize(info->fh) / 512;
 				info->to_be_mounted = true;
 			}
 			D(bug(" %d blocks\n", info->num_blocks));
@@ -287,7 +326,7 @@ int16 DiskPrime(uint32 pb, uint32 dce)
 	size_t length = ReadMacInt32(pb + ioReqCount);
 	loff_t position = ReadMacInt32(dce + dCtlPosition);
 	if (ReadMacInt16(pb + ioPosMode) & 0x100)	// 64 bit positioning
-		position = ((loff_t)ReadMacInt32(pb + ioWPosOffset) << 32) || ReadMacInt32(pb + ioWPosOffset + 4);
+		position = ((loff_t)ReadMacInt32(pb + ioWPosOffset) << 32) | ReadMacInt32(pb + ioWPosOffset + 4);
 	if ((length & 0x1ff) || (position & 0x1ff))
 		return paramErr;
 
@@ -295,7 +334,7 @@ int16 DiskPrime(uint32 pb, uint32 dce)
 	if ((ReadMacInt16(pb + ioTrap) & 0xff) == aRdCmd) {
 
 		// Read
-		actual = Sys_read(info->fh, buffer, position, length);
+		actual = Sys_read(info->fh, buffer, position + info->start_byte, length);
 		if (actual != length)
 			return readErr;
 
@@ -304,7 +343,7 @@ int16 DiskPrime(uint32 pb, uint32 dce)
 		// Write
 		if (info->read_only)
 			return wPrErr;
-		actual = Sys_write(info->fh, buffer, position, length);
+		actual = Sys_write(info->fh, buffer, position + info->start_byte, length);
 		if (actual != length)
 			return writErr;
 	}