Do the boilerplate of the IBM encoder.

arch/ibm/encoder.cc

@@ -0,0 +1,15 @@
+#include "globals.h"
+#include "record.h"
+#include "decoders/decoders.h"
+#include "encoders/encoders.h"
+#include "ibm.h"
+#include "crc.h"
+#include "sectorset.h"
+#include "writer.h"
+
+std::unique_ptr<Fluxmap> IbmEncoder::encode(
+	int physicalTrack, int physicalSide, const SectorSet& allSectors)
+{
+	return std::unique_ptr<Fluxmap>();
+}
+

arch/ibm/ibm.h

@@ -2,6 +2,7 @@
 #define IBM_H
 
 #include "decoders/decoders.h"
+#include "encoders/encoders.h"
 
 /* IBM format (i.e. ordinary PC floppies). */
 
@@ -47,52 +48,34 @@ private:
     unsigned _currentHeaderLength;
 };
 
-#if 0
-class AbstractIbmDecoder : public AbstractSoftSectorDecoder
+struct IbmParameters
+{
+	int sectorsPerTrack;
+	int sectorSize;
+	bool emitIam;
+	int startSectorId;
+	int clockSpeedKhz;
+	bool useFm;
+	int gap1;
+	int gap3;
+	uint8_t damByte;
+	std::string sectorSkew;
+};
+
+class IbmEncoder : public AbstractEncoder
 {
 public:
-    AbstractIbmDecoder(unsigned sectorIdBase):
-        _sectorIdBase(sectorIdBase)
-    {}
-    virtual ~AbstractIbmDecoder() {}
+	IbmEncoder(const IbmParameters& parameters):
+		parameters(parameters)
+	{}
 
-    SectorVector decodeToSectors(const RawRecordVector& rawRecords, unsigned physicalTrack, unsigned physicalSide);
+	virtual ~IbmEncoder() {}
 
-protected:
-    virtual int skipHeaderBytes() const = 0;
+public:
+    std::unique_ptr<Fluxmap> encode(int physicalTrack, int physicalSide, const SectorSet& allSectors);
 
 private:
-    unsigned _sectorIdBase;
+	IbmParameters parameters;
 };
 
-class IbmFmDecoder : public AbstractIbmDecoder
-{
-public:
-    IbmFmDecoder(unsigned sectorIdBase):
-        AbstractIbmDecoder(sectorIdBase)
-    {}
-
-    int recordMatcher(uint64_t fifo) const;
-
-protected:
-    int skipHeaderBytes() const
-    { return 0; }
-};
-
-class IbmMfmDecoder : public AbstractIbmDecoder
-{
-public:
-    IbmMfmDecoder(unsigned sectorIdBase):
-        AbstractIbmDecoder(sectorIdBase)
-    {}
-
-    nanoseconds_t guessClock(Fluxmap& fluxmap) const;
-    int recordMatcher(uint64_t fifo) const;
-
-protected:
-    int skipHeaderBytes() const
-    { return 3; }
-};
-#endif
-
 #endif

mkninja.sh

@@ -168,6 +168,7 @@ buildlibrary libbackend.a \
     arch/f85/decoder.cc \
     arch/fb100/decoder.cc \
     arch/ibm/decoder.cc \
+    arch/ibm/encoder.cc \
     arch/macintosh/decoder.cc \
     arch/mx/decoder.cc \
     arch/victor9k/decoder.cc \
@@ -232,6 +233,7 @@ buildlibrary libfrontend.a \
     src/fe-upgradefluxfile.cc \
     src/fe-writeamiga.cc \
     src/fe-writebrother.cc \
+    src/fe-writeibm.cc \
     src/fe-writeflux.cc \
     src/fe-writetestpattern.cc \
     src/fluxengine.cc \

src/fe-writeibm.cc

@@ -0,0 +1,97 @@
+#include "globals.h"
+#include "flags.h"
+#include "decoders/decoders.h"
+#include "encoders/encoders.h"
+#include "ibm/ibm.h"
+#include "writer.h"
+#include "fmt/format.h"
+#include "image.h"
+#include <fstream>
+
+static FlagGroup flags { &writerFlags };
+
+static IntFlag sectorsPerTrack(
+	{ "--ibm-sectors-per-track" },
+	"Number of sectors per track to write.",
+	0);
+
+static IntFlag sectorSize(
+	{ "--ibm-sector-size" },
+	"Size of the sectors to write (bytes).",
+	0);
+
+static BoolFlag emitIam(
+	{ "--ibm-emit-iam" },
+	"Whether to emit an IAM record at the start of the track.",
+	false);
+
+static IntFlag startSectorId(
+	{ "--ibm-start-sector-id" },
+	"Sector ID of first sector.",
+	1);
+
+static IntFlag clockSpeedKhz(
+	{ "--ibm-clock-rate-khz" },
+	"Clock rate of data to write.",
+	0);
+
+static BoolFlag useFm(
+	{ "--ibm-use-fm" },
+	"Write in FM mode, rather than MFM.",
+	false);
+
+static IntFlag gap1(
+	{ "--ibm-gap1-bytes" },
+	"Size of gap 1.",
+	0);
+
+static IntFlag gap3(
+	{ "--ibm-gap3-bytes" },
+	"Size of gap 3.",
+	0);
+
+static IntFlag damByte(
+	{ "--ibm-dam-byte" },
+	"Value of DAM byte to emit.",
+	0xf8);
+
+static StringFlag sectorSkew(
+	{ "--ibm-sector-skew" },
+	"Order to emit sectors.",
+	"");
+
+static ActionFlag preset1440(
+	{ "--ibm-preset-1440" },
+	"Preset parameters to a 3.5\" 1440kB disk.",
+	[] {
+		sectorsPerTrack.setDefaultValue(18);
+		sectorSize.setDefaultValue(512);
+		emitIam.setDefaultValue(true);
+		clockSpeedKhz.setDefaultValue(500);
+		gap1.setDefaultValue(0x1b);
+		gap3.setDefaultValue(0x6c);
+		sectorSkew.setDefaultValue("123456789abcdefghi");
+	});
+
+int mainWriteIbm(int argc, const char* argv[])
+{
+    setWriterDefaultInput(":c=80:h=2:s=18:b=512");
+	setWriterDefaultDest(":d=0:t=0-79:s=2");
+    flags.parseFlags(argc, argv);
+
+	IbmParameters parameters;
+	parameters.sectorsPerTrack = sectorsPerTrack;
+	parameters.sectorSize = sectorSize;
+	parameters.emitIam = emitIam;
+	parameters.clockSpeedKhz = clockSpeedKhz;
+	parameters.useFm = useFm;
+	parameters.gap1 = gap1;
+	parameters.gap3 = gap3;
+	parameters.damByte = (uint8_t) damByte;
+
+	IbmEncoder encoder(parameters);
+	writeDiskCommand(encoder);
+
+    return 0;
+}
+

src/fluxengine.cc

@@ -31,6 +31,7 @@ extern command_cb mainTestVoltages;
 extern command_cb mainUpgradeFluxFile;
 extern command_cb mainWriteAmiga;
 extern command_cb mainWriteBrother;
+extern command_cb mainWriteIbm;
 extern command_cb mainWriteFlux;
 extern command_cb mainWriteTestPattern;
 
@@ -84,6 +85,7 @@ static std::vector<Command> writeables =
 {
     { "amiga",         mainWriteAmiga,    "Writes Amiga disks.", },
     { "brother",       mainWriteBrother,  "Writes 120kB and 240kB Brother word processor disks.", },
+    { "ibm",           mainWriteIbm,      "Writes the ubiquitous IBM format disks.", },
 };
 
 static std::vector<Command> convertables =