Add the Supercard Pro decoder.

Makefile

@@ -1,8 +1,8 @@
 PACKAGES = zlib sqlite3 libusb-1.0
 
-export CFLAGS = -O3 -g --std=c++14 \
+export CFLAGS = -Os -g --std=c++14 \
 	-ffunction-sections -fdata-sections
-export LDFLAGS = -O3
+export LDFLAGS = -Os
 
 ifeq ($(OS), Windows_NT)
 export CXX = /mingw32/bin/g++

doc/using.md

@@ -221,6 +221,12 @@ directory.
   file format in a non-backwards-compatible way; this tool will upgrade flux
   files to the new format.
 
+  - `fluxengine convert`: converts various formats to various other formats.
+  You can use this to convert Catweasel or Supercard Pro flux files to
+  FluxEngine's native format, for flux files to various other formats useful
+  for debugging (including VCD which can be loaded into
+  [sigrok](http://sigrok.org)).
+
 Commands which normally take `--source` or `--dest` get a sensible default if
 left unspecified. `fluxengine read ibm` on its own will read drive 0 and
 write an `ibm.img` file.
@@ -247,25 +253,24 @@ wrote to do useful things. These are built alongside FluxEngine.
 
   - `brother120tool`: extracts files from a 120kB Brother filesystem image.
 
-  - `cwftoflux`: converts (one flavour of) CatWeasel flux file into a
-    FluxEngine flux file.
-
 ## The recommended workflow
 
-So you've just received, say, a huge pile of old Brother word processor disks containing valuable historical data, and you want to read them.
+So you've just received, say, a huge pile of old Brother word processor disks
+containing valuable historical data, and you want to read them.
 
 Typically I do this:
 
 ```
-$ fluxengine read brother -s :d=0 -o brother.img --write-flux=brother.flux
+$ fluxengine read brother -s :d=0 -o brother.img --write-flux=brother.flux --write-svg=brother.svg
 ```
 
 This will read the disk in drive 0 and write out a filesystem image. It'll
-also copy the flux to brother.flux. If I then need to tweak the settings, I
-can rerun the decode without having to physically touch the disk like this:
+also copy the flux to brother.flux and write out an SVG visualisation. If I
+then need to tweak the settings, I can rerun the decode without having to
+physically touch the disk like this:
 
 ```
-$ fluxengine read brother -s brother.flux -o brother.img
+$ fluxengine read brother -s brother.flux -o brother.img --write-svg=brother.svg
 ```
 
 Apart from being drastically faster, this avoids touching the (potentially

mkninja.sh

@@ -208,6 +208,7 @@ buildlibrary libfrontend.a \
     src/fe-readvictor9k.cc \
     src/fe-readzilogmcz.cc \
     src/fe-rpm.cc \
+    src/fe-scptoflux.cc \
     src/fe-seek.cc \
     src/fe-testbulktransport.cc \
     src/fe-upgradefluxfile.cc \

src/fe-scptoflux.cc

@@ -0,0 +1,167 @@
+#include "globals.h"
+#include "fluxmap.h"
+#include "sql.h"
+#include "bytes.h"
+#include "protocol.h"
+#include "fmt/format.h"
+#include <fstream>
+
+struct ScpHeader
+{
+    char file_id[3];       // file ID - 'SCP'
+    uint8_t version;       // major/minor in nibbles
+    uint8_t type;          // disk type - subclass/class in nibbles
+    uint8_t revolutions;   // up to 5
+    uint8_t start_track;   // 0..165
+    uint8_t end_track;     // 0..165
+    uint8_t flags;         // see below
+    uint8_t cell_width;    // in bits, 0 meaning 16
+    uint8_t heads;         // 0 = both, 1 = side 0 only, 2 = side 1 only
+    uint8_t resolution;    // 25ns * (resolution+1)
+    uint8_t checksum[4];   // of data after this point
+    uint8_t track[165][4]; // track offsets, not necessarily 165
+};
+
+struct ScpTrack
+{
+    char track_id[3];      // 'TRK'
+    uint8_t strack;        // SCP track number
+    struct
+    {
+        uint8_t index[4];  // time for one revolution
+        uint8_t length[4]; // number of bitcells
+        uint8_t offset[4]; // offset to bitcell data, relative to track header
+    }
+    revolution[5];
+};
+
+static std::ifstream inputFile;
+static sqlite3* outputDb;
+static ScpHeader header;
+static nanoseconds_t resolution;
+static int startSide;
+static int endSide;
+
+static void syntax()
+{
+    std::cout << "Syntax: fluxengine convert cwftoflux <cwffile> <fluxfile>\n";
+    exit(0);
+}
+
+static void check_for_error()
+{
+    if (inputFile.fail())
+        Error() << fmt::format("I/O error: {}", strerror(errno));
+}
+
+static int trackno(int strack)
+{
+    if (startSide == endSide)
+        return strack;
+    return strack >> 1;
+}
+
+static int headno(int strack)
+{
+    if (startSide == endSide)
+        return startSide;
+    return strack & 1;
+}
+
+static void read_header()
+{
+    inputFile.read((char*) &header, sizeof(header));
+    check_for_error();
+
+    if ((header.file_id[0] != 'S')
+            || (header.file_id[1] != 'C')
+            || (header.file_id[2] != 'P'))
+        Error() << "input not a SCP file";
+
+    resolution = 25 * (header.resolution + 1);
+    startSide = (header.heads == 2) ? 1 : 0;
+    endSide = (header.heads == 1) ? 0 : 1;
+
+    if ((header.cell_width != 0) && (header.cell_width != 16))
+        Error() << "currently only 16-bit cells are supported";
+
+    std::cout << fmt::format("tracks {}-{}, heads {}-{}\n",
+        trackno(header.start_track), trackno(header.end_track), startSide, endSide);
+    std::cout << fmt::format("sample resolution: {} ns\n", resolution);
+}
+
+static void read_track(int strack)
+{
+    uint32_t offset = Bytes(header.track[strack], 4).reader().read_le32();
+
+    ScpTrack trackheader;
+    inputFile.seekg(offset, std::ios::beg);
+    inputFile.read((char*) &trackheader, sizeof(trackheader));
+    check_for_error();
+
+    if ((trackheader.track_id[0] != 'T')
+            || (trackheader.track_id[1] != 'R')
+            || (trackheader.track_id[2] != 'K'))
+        Error() << "corrupt SCP file";
+
+    std::cout << fmt::format("{}.{}: ", trackno(strack), headno(strack))
+        << std::flush;
+
+    Fluxmap fluxmap;
+    nanoseconds_t pending = 0;
+    for (int revolution = 0; revolution < header.revolutions; revolution++)
+    {
+        if (revolution != 0)
+            fluxmap.appendIndex();
+
+        uint32_t datalength = Bytes(trackheader.revolution[revolution].length, 4).reader().read_le32();
+        uint32_t dataoffset = Bytes(trackheader.revolution[revolution].offset, 4).reader().read_le32();
+
+        Bytes data(datalength*2);
+        inputFile.seekg(dataoffset + offset, std::ios::beg);
+        inputFile.read((char*) data.begin(), data.size());
+        check_for_error();
+
+        ByteReader br(data);
+        for (int cell = 0; cell < datalength; cell++)
+        {
+            uint16_t interval = br.read_be16();
+            if (interval)
+            {
+                fluxmap.appendInterval((interval + pending) * resolution / NS_PER_TICK);
+                fluxmap.appendPulse();
+                pending = 0;
+            }
+            else
+                pending += interval;
+        }
+    }
+
+    std::cout << fmt::format(" {} ms in {} output bytes\n",
+        fluxmap.duration() / 1e6, fluxmap.bytes());
+    sqlWriteFlux(outputDb, trackno(strack), headno(strack), fluxmap);
+}
+
+int mainConvertScpToFlux(int argc, const char* argv[])
+{
+    if (argc != 3)
+        syntax();
+    
+    inputFile.open(argv[1], std::ios::in | std::ios::binary);
+    if (!inputFile.is_open())
+		Error() << fmt::format("cannot open input file '{}'", argv[1]);
+
+    outputDb = sqlOpen(argv[2], SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE);
+    sqlPrepareFlux(outputDb);
+    sqlWriteIntProperty(outputDb, "version", FLUX_VERSION_CURRENT);
+    sqlStmt(outputDb, "BEGIN;");
+
+    read_header();
+    inputFile.seekg(sizeof(header), std::ios::beg);
+    for (unsigned i=header.start_track; i<=header.end_track; i++)
+        read_track(i);
+
+    sqlStmt(outputDb, "COMMIT;");
+    sqlClose(outputDb);
+    return 0;
+}

src/fluxengine.cc

@@ -6,6 +6,7 @@ extern command_cb mainErase;
 extern command_cb mainConvertCwfToFlux;
 extern command_cb mainConvertFluxToAu;
 extern command_cb mainConvertFluxToVcd;
+extern command_cb mainConvertScpToFlux;
 extern command_cb mainInspect;
 extern command_cb mainReadADFS;
 extern command_cb mainReadAESLanier;
@@ -83,6 +84,7 @@ static std::vector<Command> writeables =
 static std::vector<Command> convertables =
 {
     { "cwftoflux",     mainConvertCwfToFlux, "Converts CatWeasel stream files to flux.", },
+    { "scptoflux",     mainConvertScpToFlux, "Converts Supercard Pro stream files to flux.", },
     { "fluxtoau",      mainConvertFluxToAu,  "Converts (one track of a) flux file to an .au audio file.", },
     { "fluxtovcd",     mainConvertFluxToVcd, "Converts (one track of a) flux file to a VCD file.", },
 };