Add a skeleton for the AES Lanier disks.

lib/aeslanier/aeslanier.h

@@ -0,0 +1,18 @@
+#ifndef AESLANIER_H
+#define AESLANIER_H
+
+class Sector;
+class Fluxmap;
+
+class AesLanierDecoder : public AbstractDecoder
+{
+public:
+    virtual ~AesLanierDecoder() {}
+
+    SectorVector decodeToSectors(
+        const RawRecordVector& rawRecords, unsigned physicalTrack);
+	nanoseconds_t guessClock(Fluxmap& fluxmap) const;
+    int recordMatcher(uint64_t fifo) const;
+};
+
+#endif

lib/aeslanier/decoder.cc

@@ -0,0 +1,40 @@
+#include "globals.h"
+#include "decoders.h"
+#include "aeslanier.h"
+#include "crc.h"
+#include "fluxmap.h"
+#include "sector.h"
+#include "bytes.h"
+#include <string.h>
+
+/* Aaaah, M2FM, the encoding which time forgot! Justly so. It's like MFM, but not.
+ * Data bits are written in the middle of the cell. Clock bits are written at the
+ * beginnign of 
+SectorVector AesLanierDecoder::decodeToSectors(const RawRecordVector& rawRecords, unsigned)
+{
+    std::vector<std::unique_ptr<Sector>> sectors;
+
+    for (auto& rawrecord : rawRecords)
+    {
+        const auto& rawdata = rawrecord->data;
+        const auto& rawbytes = toBytes(rawdata);
+        const auto& bytes = decodeFmMfm(rawdata);
+
+	}
+
+	return sectors;
+}
+
+nanoseconds_t AesLanierDecoder::guessClock(Fluxmap& fluxmap) const
+{
+    return fluxmap.guessClock() / 2;
+}
+
+int AesLanierDecoder::recordMatcher(uint64_t fifo) const
+{
+    uint64_t masked = fifo & 0xffffffffffffULL;
+    // if (masked == AMIGA_SECTOR_RECORD)
+	// 	return 64;
+    return 0;
+}
+

lib/decoders/fmmfm.cc

@@ -15,10 +15,10 @@ std::vector<uint8_t> decodeFmMfm(const std::vector<bool> bits)
      *
      * So we just need to extract all the odd bits.
      * 
-     * MFM is slightly more complicated, where the first bit of each pair can
-     * be either 0 or 1... but the second bit is always the data bit, and at
-     * this point we simply don't care what the first bit is, so decoding MFM
-     * uses just the same code!
+     * MFM and M2FM are slightly more complicated, where the first bit of each
+     * pair can be either 0 or 1... but the second bit is always the data bit,
+     * and at this point we simply don't care what the first bit is, so
+     * decoding MFM uses just the same code!
      */
 
     std::vector<uint8_t> bytes;

meson.build

@@ -85,6 +85,15 @@ encoderlib = shared_library('encoderlib',
     link_with: [felib, fmtlib]
 )
 
+aeslanierdecoderlib = shared_library('aeslanierdecoderlib',
+    [
+		'lib/aeslanier/decoder.cc',
+    ],
+    include_directories: [feinc, fmtinc, decoderinc],
+    link_with: [felib, fmtlib, decoderlib]
+)
+aeslanierinc = include_directories('lib/aeslanier')
+
 amigadecoderlib = shared_library('amigadecoderlib',
     [
 		'lib/amiga/decoder.cc',
@@ -158,6 +167,7 @@ victor9kinc = include_directories('lib/victor9k')
 executable('fe-erase',             ['src/fe-erase.cc'],             include_directories: [feinc], link_with: [felib, writerlib])
 executable('fe-inspect',           ['src/fe-inspect.cc'],           include_directories: [feinc, fmtinc, decoderinc], link_with: [felib, readerlib, decoderlib, fmtlib])
 executable('fe-readadfs',          ['src/fe-readadfs.cc'],          include_directories: [feinc, fmtinc, decoderinc, ibminc], link_with: [felib, readerlib, decoderlib, ibmdecoderlib, fmtlib])
+executable('fe-readaeslanier',     ['src/fe-readaeslanier.cc'],     include_directories: [feinc, fmtinc, decoderinc, aeslanierinc], link_with: [felib, readerlib, decoderlib, aeslanierdecoderlib, fmtlib])
 executable('fe-readamiga',         ['src/fe-readamiga.cc'],         include_directories: [feinc, fmtinc, decoderinc, amigainc], link_with: [felib, readerlib, decoderlib, amigadecoderlib, fmtlib])
 executable('fe-readampro',         ['src/fe-readampro.cc'],         include_directories: [feinc, fmtinc, decoderinc, ibminc], link_with: [felib, readerlib, decoderlib, ibmdecoderlib, fmtlib])
 executable('fe-readapple2',        ['src/fe-readapple2.cc'],        include_directories: [feinc, fmtinc, decoderinc, apple2inc], link_with: [felib, readerlib, decoderlib, apple2decoderlib, fmtlib])

src/fe-readaeslanier.cc

@@ -0,0 +1,28 @@
+#include "globals.h"
+#include "flags.h"
+#include "reader.h"
+#include "fluxmap.h"
+#include "decoders.h"
+#include "image.h"
+#include "sector.h"
+#include "sectorset.h"
+#include "record.h"
+#include "aeslanier.h"
+#include <fmt/format.h>
+
+static StringFlag outputFilename(
+    { "--output", "-o" },
+    "The output image file to write to.",
+    "aeslanier.img");
+
+int main(int argc, const char* argv[])
+{
+	setReaderDefaultSource(":t=0-79:s=0");
+    setReaderRevolutions(2);
+    Flag::parseFlags(argc, argv);
+
+	AesLanierDecoder decoder;
+	readDiskCommand(decoder, outputFilename);
+    return 0;
+}
+