Apple-2-Tools/dmolony-DiskBrowser
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tidying

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This commit is contained in:
Denis Molony 2016-12-04 13:33:21 +11:00
parent f0c1c538eb
commit bce29f8714
3 changed files with 87 additions and 89 deletions
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6
src/com/bytezone/diskbrowser/disk/NibDisk.java
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@ -7,7 +7,7 @@ import java.io.IOException;
public class NibDisk
{
private final Nibblizer nibbler;
// private final Nibblizer nibbler;
final File file;
int tracks;
@ -24,7 +24,7 @@ public class NibDisk
{
this.file = file;
byte[] trackBuffer = new byte[6656];
nibbler = new Nibblizer (file);
// nibbler = new Nibblizer (file);
try
{
@ -38,7 +38,7 @@ public class NibDisk
int offset = 0;
while (true)
{
offset = nibbler.findBytes (trackBuffer, offset, test);
offset = Nibblizer.findBytes (trackBuffer, offset, test);
if (offset < 0)
break;
System.out.printf ("found at %04X%n", offset);

138
src/com/bytezone/diskbrowser/disk/Nibblizer.java
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@ -14,6 +14,10 @@ public class Nibblizer
private static final int DOS = 0;
private static final int PRODOS = 1;
private static final int BLOCK_SIZE = 256;
private static final int TRACK_SIZE = 4096;
private static final int RAW_BUFFER_SIZE = 342;
private static final int BUFFER_WITH_CHECKSUM_SIZE = RAW_BUFFER_SIZE + 1;
private static byte[] writeTranslateTable =
{ (byte) 0x96, (byte) 0x97, (byte) 0x9A, (byte) 0x9B, (byte) 0x9D, (byte) 0x9E,
@ -29,10 +33,10 @@ public class Nibblizer
(byte) 0xF5, (byte) 0xF6, (byte) 0xF7, (byte) 0xF9, (byte) 0xFA, (byte) 0xFB,
(byte) 0xFC, (byte) 0xFD, (byte) 0xFE, (byte) 0xFF };
private static byte[] readTranslateTable = new byte[106];
private static byte[] readTranslateTable = new byte[106]; // skip first 150 blanks
// this array is just here for testing - it matches the example in Beneath Apple Prodos
private static byte[] xor =
private static byte[] testData =
{ (byte) 0x00, (byte) 0x00, (byte) 0x03, (byte) 0x00, (byte) 0xFA, (byte) 0x55,
(byte) 0x53, (byte) 0x45, (byte) 0x52, (byte) 0x53, (byte) 0x2E, (byte) 0x44,
(byte) 0x49, (byte) 0x53, (byte) 0x4B, (byte) 0x00, //
@ -89,15 +93,16 @@ public class Nibblizer
{
for (int i = 0; i < writeTranslateTable.length; i++)
{
int j = (writeTranslateTable[i] & 0xFF) - 150;
readTranslateTable[j] = (byte) (i + 1);
int j = (writeTranslateTable[i] & 0xFF) - 150; // skip first 150 blanks
readTranslateTable[j] = (byte) (i + 1); // offset by 1 to avoid zero
}
}
private final byte[] decode1 = new byte[343];
private final byte[] decode2 = new byte[342];
private final byte[] encode1 = new byte[342];
private final byte[] encode2 = new byte[343];
private final byte[] decode1 = new byte[BUFFER_WITH_CHECKSUM_SIZE];
private final byte[] decode2 = new byte[RAW_BUFFER_SIZE];
private final byte[] encode1 = new byte[RAW_BUFFER_SIZE];
private final byte[] encode2 = new byte[BUFFER_WITH_CHECKSUM_SIZE];
private final File file;
@ -107,10 +112,10 @@ public class Nibblizer
if (false) // test with the Beneath Apple Prodos example
{
byte[] testBuffer = decode6and2 (encode6and2 (xor), 0);
byte[] testBuffer = decode6and2 (encode6and2 (testData), 0);
for (int i = 0; i < 256; i++)
if (xor[i] != testBuffer[i])
for (int i = 0; i < BLOCK_SIZE; i++)
if (testData[i] != testBuffer[i])
System.out.println ("bollocks");
return;
@ -145,8 +150,9 @@ public class Nibblizer
if (!dataField.isValid ())
return false;
int offset = addressField.track * 4096 + interleave[DOS][addressField.sector] * 256;
System.arraycopy (dataField.dataBuffer, 0, diskBuffer, offset, 256);
int offset = addressField.track * TRACK_SIZE
+ interleave[DOS][addressField.sector] * BLOCK_SIZE;
System.arraycopy (dataField.dataBuffer, 0, diskBuffer, offset, BLOCK_SIZE);
ptr += dataField.size ();
ptr += skipBytes (buffer, ptr, (byte) 0xFF); // gap3
@ -179,77 +185,70 @@ public class Nibblizer
int val = (buffer[offset++] & 0xFF) - 150;
byte trans = readTranslateTable[val];
assert trans != 0;
decode1[i] = (byte) ((trans - 1) << 2);
decode1[i] = (byte) ((trans - 1) << 2); // readjust by 1 (see above)
}
byte chk = 0;
for (int i = 342; i > 0; i--)
for (int i = RAW_BUFFER_SIZE; i > 0; i--)
{
decode2[i - 1] = (byte) (decode1[i] ^ chk);
chk = decode2[i - 1];
}
byte[] decodedBuffer = new byte[256];
byte[] decodedBuffer = new byte[BLOCK_SIZE];
for (int i = 0; i < 256; i++)
for (int i = 0; i < BLOCK_SIZE; i++)
decodedBuffer[i] = decode2[i + 86];
for (int i = 0; i < 84; i++)
for (int i = 0; i < 86; i++)
{
int val = decode2[i] & 0xFF;
int b1 = reverse ((val & 0x0C) >> 2);
int b2 = reverse ((val & 0x30) >> 4);
int b3 = reverse ((val & 0xC0) >> 6);
byte val = decode2[i];
decodedBuffer[i] |= b1;
decodedBuffer[i + 86] |= b2;
decodedBuffer[i + 172] |= b3;
}
decodedBuffer[i] |= reverse ((val & 0x0C) >> 2);
decodedBuffer[i + 86] |= reverse ((val & 0x30) >> 4);
for (int i = 84; i < 86; i++)
{
int val = decode2[i] & 0xFF;
int b1 = reverse ((val & 0x0C) >> 2);
int b2 = reverse ((val & 0x30) >> 4);
decodedBuffer[i] |= b1;
decodedBuffer[i + 86] |= b2;
if (i < 84)
decodedBuffer[i + 172] |= reverse ((val & 0xC0) >> 6);
}
return decodedBuffer;
}
// convert 256 data bytes into 342 translated bytes plus a checksum
private byte[] encode6and2 (byte[] buffer)
{
byte[] encodedBuffer = new byte[343];
byte[] encodedBuffer = new byte[BUFFER_WITH_CHECKSUM_SIZE];
for (int i = 0; i < 256; i++)
// move data buffer down to make room for the 86 extra bytes
for (int i = 0; i < BLOCK_SIZE; i++)
encode1[i + 86] = buffer[i];
for (int i = 0; i < 84; i++)
// build extra 86 bytes from the bits stripped from the data bytes
for (int i = 0; i < 86; i++)
{
int b1 = reverse (buffer[i] & 0x03) << 2;
int b2 = reverse (buffer[i + 86] & 0x03) << 4;
int b3 = reverse (buffer[i + 172] & 0x03) << 6;
encode1[i] = (byte) (b1 | b2 | b3);
if (i < 84)
{
int b3 = reverse (buffer[i + 172] & 0x03) << 6;
encode1[i] = (byte) (b1 | b2 | b3);
}
else
encode1[i] = (byte) (b1 | b2);
}
for (int i = 84; i < 86; i++)
// convert into checksum bytes
byte checksum = 0;
for (int i = 0; i < RAW_BUFFER_SIZE; i++)
{
int b1 = reverse (buffer[i] & 0x03) << 2;
int b2 = reverse (buffer[i + 86] & 0x03) << 4;
encode1[i] = (byte) (b1 | b2);
encode2[i] = (byte) (checksum ^ encode1[i]);
checksum = encode1[i];
}
encode2[RAW_BUFFER_SIZE] = checksum; // add checksum to the end
byte chk = 0;
for (int i = 0; i < 342; i++)
{
encode2[i] = (byte) (chk ^ encode1[i]);
chk = encode1[i];
}
encode2[342] = chk;
for (int i = 0; i < 343; i++)
// remove two bits and convert to translated bytes
for (int i = 0; i < BUFFER_WITH_CHECKSUM_SIZE; i++)
encodedBuffer[i] = writeTranslateTable[(encode2[i] & 0xFC) / 4];
return encodedBuffer;
@ -261,7 +260,7 @@ public class Nibblizer
return bits == 1 ? 2 : bits == 2 ? 1 : bits;
}
int skipBytes (byte[] buffer, int offset, byte skipValue)
private int skipBytes (byte[] buffer, int offset, byte skipValue)
{
int count = 0;
while (offset < buffer.length && buffer[offset++] == skipValue)
@ -280,30 +279,28 @@ public class Nibblizer
return text.toString ();
}
int findBytes (byte[] buffer, int offset, byte[] valueBuffer)
static int findBytes (byte[] buffer, int offset, byte[] valueBuffer)
{
int length = valueBuffer.length;
int ptr = offset + length;
while (ptr < buffer.length)
while (offset + valueBuffer.length < buffer.length)
{
if (matchBytes (buffer, ptr - length, valueBuffer))
return ptr - length;
++ptr;
if (matchBytes (buffer, offset, valueBuffer))
return offset;
++offset;
}
return -1;
}
private boolean matchBytes (byte[] buffer, int offset, byte[] valueBuffer)
private static boolean matchBytes (byte[] buffer, int offset, byte[] valueBuffer)
{
for (int i = 0; i < valueBuffer.length; i++)
{
if (offset >= buffer.length)
if (buffer.length - offset < valueBuffer.length)
return false;
int ptr = 0;
while (ptr < valueBuffer.length)
if (buffer[offset++] != valueBuffer[ptr++])
return false;
if (buffer[offset++] != valueBuffer[i])
return false;
}
return true;
}
@ -368,10 +365,11 @@ public class Nibblizer
{
valid = true;
dataBuffer = decode6and2 (buffer, offset + 3);
if (!matchBytes (buffer, offset + 346, epilogue))
if (!matchBytes (buffer, offset + 3 + BUFFER_WITH_CHECKSUM_SIZE, epilogue))
{
System.out.print (" bad data epilogue: ");
System.out.println (listBytes (buffer, offset + 346, 3));
System.out
.println (listBytes (buffer, offset + 3 + BUFFER_WITH_CHECKSUM_SIZE, 3));
}
}
else

32
src/com/bytezone/diskbrowser/infocom/Header.java
View File

@ -99,33 +99,33 @@ class Header extends InfocomAbstractFile
text.append (String.format ("Version %d%n", version));
text.append ("\nDynamic memory:\n");
text.append (String.format (" Abbreviation table %04X %,6d%n",
abbreviationsTable, abbreviationsTable));
abbreviationsTable, abbreviationsTable));
text.append (String.format (" Objects table %04X %,6d%n", objectTable,
objectTable));
objectTable));
text.append (String.format (" Global variables %04X %,6d%n", globalsOffset,
globalsOffset));
globalsOffset));
text.append ("\nStatic memory:\n");
text.append (String.format (" Grammar table etc %04X %,6d%n", staticMemory,
staticMemory));
staticMemory));
text.append (String.format (" Dictionary %04X %,6d%n", dictionaryOffset,
dictionaryOffset));
dictionaryOffset));
text.append ("\nHigh memory:\n");
text.append (String.format (" ZCode %04X %,6d%n", highMemory,
highMemory));
text.append (
String.format (" ZCode %04X %,6d%n", highMemory, highMemory));
text.append (String.format (" Program counter %04X %,6d%n", programCounter,
programCounter));
text.append (String.format ("\nFile length %05X %,6d%n", fileLength,
fileLength));
text.append (String.format ("Checksum %04X %,6d%n", checksum,
checksum));
text.append (String.format ("%nZString offset %05X %,6d%n", stringPointer,
stringPointer));
programCounter));
text.append (
String.format ("\nFile length %05X %,7d%n", fileLength, fileLength));
text.append (
String.format ("Checksum %04X %,6d%n", checksum, checksum));
text.append (String.format ("%nZString offset %05X %,7d%n", stringPointer,
stringPointer));
text.append (String.format ("Total strings %d%n",
stringManager.strings.size ()));
stringManager.strings.size ()));
text.append (String.format ("Total objects %d%n",
objectManager.list.size ()));
objectManager.list.size ()));
return text.toString ();
}