Massive overhaul of how the physical/logical layout mapping is done, to make it

more consistent and bidirectional everywhere and just generally better.
Hopefully this fixes that pesky 1581 problem.

Author: davidgiven

arch/ibm/decoder.cc

@@ -141,7 +141,7 @@ class IbmDecoder : public Decoder
 
         IbmDecoderProto::TrackdataProto trackdata;
         getTrackFormat(
-            trackdata, _sector->physicalTrack, _sector->physicalHead);
+            trackdata, _sector->physicalTrack, _sector->physicalSide);
 
         _sector->logicalTrack = br.read_8();
         _sector->logicalSide = br.read_8();
@@ -154,7 +154,8 @@ class IbmDecoder : public Decoder
                 Sector::DATA_MISSING; /* correct but unintuitive */
 
         if (trackdata.ignore_side_byte())
-            _sector->logicalSide = _sector->physicalHead;
+            _sector->logicalSide =
+                Layout::remapSidePhysicalToLogical(_sector->physicalSide);
         _sector->logicalSide ^= trackdata.invert_side_byte();
         if (trackdata.ignore_track_byte())
             _sector->logicalTrack = _sector->physicalTrack;

arch/ibm/encoder.cc

@@ -107,34 +107,15 @@ class IbmEncoder : public Encoder
     }
 
 public:
-    std::shared_ptr<const Sector> getSector(
-        const Location& location, const Image& image, unsigned sectorId)
-    {
-        IbmEncoderProto::TrackdataProto trackdata;
-        getEncoderTrackData(trackdata, location.logicalTrack, location.head);
-
-        if (trackdata.swap_sides())
-        {
-            Location newLocation = location;
-            newLocation.head ^= 1;
-            auto sector = std::make_shared<Sector>(
-                *Encoder::getSector(newLocation, image, sectorId));
-            sector->logicalSide ^= 1;
-            return sector;
-        }
-        else
-            return image.get(location.logicalTrack, location.head, sectorId);
-    }
-
     std::unique_ptr<Fluxmap> encode(const Location& location,
         const std::vector<std::shared_ptr<const Sector>>& sectors,
         const Image& image) override
     {
         IbmEncoderProto::TrackdataProto trackdata;
-        getEncoderTrackData(trackdata, location.logicalTrack, location.head);
+        getEncoderTrackData(trackdata, location.logicalTrack, location.logicalSide);
 
         auto& trackLayout =
-            Layout::getLayoutOfTrack(location.logicalTrack, location.head);
+            Layout::getLayoutOfTrack(location.logicalTrack, location.logicalSide);
 
         auto writeBytes = [&](const Bytes& bytes)
         {

arch/ibm/ibm.proto

@@ -33,7 +33,6 @@ message IbmEncoderProto {
 		optional int32 gap1 = 10            [default=50, (help) = "size of gap 2 (the post-ID gap)"];
 		optional int32 gap2 = 11            [default=22, (help) = "size of gap 3 (the pre-data gap)"];
 		optional int32 gap3 = 12            [default=80, (help) = "size of gap 4 (the post-data or format gap)"];
-		optional bool swap_sides = 14       [default=false, (help) = "swap the sides of the disk"];
 		optional bool invert_side_byte = 19 [default=false, (help) = "invert the side byte before writing"];
 		optional int32 gap_fill_byte = 18   [default=0x9254, (help) = "16-bit raw bit pattern of gap fill byte"];
 		optional double target_rotational_period_ms = 1 [default=200, (help) = "rotational period of target disk"];

arch/micropolis/decoder.cc

@@ -127,7 +127,7 @@ class MicropolisDecoder : public Decoder
 			return;
 
 		_sector->logicalTrack = br.read_8();
-		_sector->logicalSide = _sector->physicalHead;
+		_sector->logicalSide = _sector->physicalSide;
 		_sector->logicalSector = br.read_8();
 		if (_sector->logicalSector > 15)
 			return;

arch/mx/decoder.cc

@@ -66,7 +66,7 @@ class MxDecoder : public Decoder
 		uint16_t wantChecksum = br.read_be16();
 
 		_sector->logicalTrack = _sector->physicalTrack;
-		_sector->logicalSide = _sector->physicalHead;
+		_sector->logicalSide = _sector->physicalSide;
 		_sector->logicalSector = _currentSector;
 		_sector->data = bytes.slice(0, SECTOR_SIZE).swab();
 		_sector->status = (gotChecksum == wantChecksum) ? Sector::OK : Sector::BAD_CHECKSUM;

arch/northstar/decoder.cc

@@ -150,7 +150,7 @@ class NorthstarDecoder : public Decoder
 		auto bytes = decodeFmMfm(rawbits).slice(0, recordSize);
 		ByteReader br(bytes);
 
-		_sector->logicalSide = _sector->physicalHead;
+		_sector->logicalSide = _sector->physicalSide;
 		_sector->logicalSector = _hardSectorId;
 		_sector->logicalTrack = _sector->physicalTrack;
 

arch/victor9k/encoder.cc

@@ -168,7 +168,7 @@ class Victor9kEncoder : public Encoder
         const Image& image) override
     {
         Victor9kEncoderProto::TrackdataProto trackdata;
-        getTrackFormat(trackdata, location.logicalTrack, location.head);
+        getTrackFormat(trackdata, location.logicalTrack, location.logicalSide);
 
         unsigned bitsPerRevolution = (trackdata.rotational_period_ms() * 1e3) /
                                      trackdata.clock_period_us();