Feature: rudimentary support for PalmOS .prc binaries.

src/Drivers/Common.items

@@ -82,6 +82,7 @@ by the PreBuild.targets file.
     <ProjectReference Include="$(SolutionDir)Environments\NeoGeo\NeoGeo.csproj" />
     <ProjectReference Include="$(SolutionDir)Environments\OpenVMS\OpenVMS.csproj" />
     <ProjectReference Include="$(SolutionDir)Environments\OS2\OS2.csproj" />
+    <ProjectReference Include="$(SolutionDir)Environments\PalmOS\PalmOS.csproj" />
     <ProjectReference Include="$(SolutionDir)Environments\Pdp10Env\Pdp10Env.csproj" />
     <ProjectReference Include="$(SolutionDir)Environments\Ps3\Ps3.csproj" />
     <ProjectReference Include="$(SolutionDir)Environments\RiscOS\RiscOS.csproj" />

src/Drivers/reko.config

@@ -78,6 +78,7 @@
       <Loader Extension="prg" Type="Reko.Environments.C64.PrgLoader,Reko.Environments.C64"                          Description="C64 PRG image" />
       <Loader Extension="rsrc" Type="Reko.Environments.MacOS.Classic.RsrcLoader,Reko.Environments.MacOS"            Description="MacOS classic resource fork" Label="rsrc" />
       <Loader Extension="tar" Type="Reko.ImageLoaders.Archives.TarLoader,Reko.ImageLoaders.Archives"                Description="Tarball" />
+      <Loader Extension="prc" Type="Reko.Environments.PalmOS.PRC.PrcLoader,Reko.Environments.PalmOS"                Description="PalmOS executable" />
 
       <!-- The following loaders have known file formats but no specified file extensions -->
       <Loader Label="NintendoDol" Type="Reko.ImageLoaders.Dol.DolLoader,Reko.ImageLoaders.Dol"                      Description="Nintendo DOL image format" />
@@ -444,6 +445,11 @@
                    Type="Reko.Environments.Ps3.Ps3Platform,Reko.Environments.Ps3">
       </Environment>
 
+      <Environment Name="palmOS" 
+                   Description="Palm OS" 
+                   Type="Reko.Environments.PalmOS.PalmOSPlatform,Reko.Environments.PalmOSPlatform">
+      </Environment>
+
       <Environment Name="xbox"
                    Description="Xbox"
                    Type="Reko.Environments.Xbox.XboxPlatform,Reko.Environments.Xbox">

src/Environments/MacOS/Classic/AppleDoubleLoader.cs

@@ -55,7 +55,7 @@ public override Program LoadProgram(Address? addrLoad)
         {
             addrLoad ??= PreferredBaseAddress;
             var cfgSvc = Services.RequireService<IConfigurationService>();
-            var rdr = new Core.Memory.BeImageReader(RawImage);
+            var rdr = new BeImageReader(RawImage);
             var hdr = rdr.ReadStruct<Header>();
             var things = new Entry[hdr.cEntries];
             for (int i = 0; i < things.Length; ++i)

src/Environments/PalmOS/PRC/Code0Resource.cs

@@ -0,0 +1,32 @@
+#region License
+/* 
+ * Copyright (C) 1999-2023 John Källén.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Reko.Environments.PalmOS.PRC
+{
+    public class Code0Resource
+    {
+    }
+}

src/Environments/PalmOS/PRC/PrcHeader.cs

@@ -0,0 +1,46 @@
+#region License
+/* 
+ * Copyright (C) 1999-2023 John Källén.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Reko.Environments.PalmOS.PRC
+{
+    public class PrcHeader
+    {
+        public string? name;
+        public ushort flags;
+        public ushort version;
+        public uint create_time;
+        public uint mod_time;
+        public uint backup_time;
+        public uint mod_num;
+        public uint app_info;
+        public uint sort_info;
+        public uint type;
+        public uint id;
+        public uint unique_id_seed;
+        public uint next_record_list;
+        public ushort num_records;
+    }
+}

src/Environments/PalmOS/PRC/PrcLoader.cs

@@ -0,0 +1,180 @@
+#region License
+/* 
+ * Copyright (C) 1999-2023 John Källén.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#endregion
+
+using Reko.Core;
+using Reko.Core.Configuration;
+using Reko.Core.Loading;
+using Reko.Core.Memory;
+using Reko.Core.Services;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Reko.Environments.PalmOS.PRC
+{
+    /// <summary>
+    /// Loads PalmOS PRC files.
+    /// </summary>
+
+    public class PrcLoader : ProgramImageLoader
+    {
+        // https://web.mit.edu/tytso/www/pilot/prc-format.html
+
+        public PrcLoader(IServiceProvider services, ImageLocation imageLocation, byte[] imgRaw)
+            : base(services, imageLocation, imgRaw)
+        {
+        }
+
+        public override Address PreferredBaseAddress
+        {
+            get { return Address.Ptr32(0x00100000); }
+            set { throw new NotImplementedException(); }
+        }
+
+
+        public override Program LoadProgram(Address? addrLoad)
+        {
+            addrLoad ??= PreferredBaseAddress;
+            var rdr = new BeImageReader(base.RawImage);
+            var cfgSvc = Services.RequireService<IConfigurationService>();
+
+            var header = LoadHeader(rdr);
+            if (header is null)
+                throw new BadImageFormatException();
+            var rsrcHeaders = LoadResourceHeaders(rdr, header.num_records);
+            if (rsrcHeaders is null)
+                throw new BadImageFormatException();
+            var segments = LoadResources(rdr, rsrcHeaders, addrLoad);
+            if (segments is null)
+                throw new BadImageFormatException();
+
+            var arch = cfgSvc.GetArchitecture("m68k")!;
+            var platform = new PalmOSPlatform(Services, arch, "palmOS");
+            var program = new Program(segments, arch, platform);
+            return program;
+        }
+
+        private PrcHeader? LoadHeader(BeImageReader rdr)
+        {
+            var header = new PrcHeader();
+            var abName = rdr.ReadBytes(0x20);
+            if (abName.Length != 0x20)
+                return null;
+            int i = Array.IndexOf(abName, 0);
+            if (i < 0)
+                header.name = Encoding.ASCII.GetString(abName);
+            else
+                header.name = Encoding.ASCII.GetString(abName, 0, i);
+
+            if (!rdr.TryReadBeUInt16(out header.flags))
+                return null;
+            if (!rdr.TryReadBeUInt16(out header.version))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.create_time))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.mod_time))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.backup_time))
+                return null;
+
+            if (!rdr.TryReadBeUInt32(out header.mod_num))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.app_info))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.sort_info))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.type))
+                return null;
+
+            if (!rdr.TryReadBeUInt32(out header.id))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.unique_id_seed))
+                return null;
+            if (!rdr.TryReadBeUInt32(out header.next_record_list))
+                return null;
+            if (!rdr.TryReadBeUInt16(out header.num_records))
+                return null;
+
+            return header;
+        }
+
+        private List<ResourceHeader>? LoadResourceHeaders(BeImageReader rdr, uint cRecords)
+        {
+            var headers = new List<ResourceHeader>();
+            for (uint i = 0; i < cRecords; ++i)
+            {
+                var rhdr = new ResourceHeader();
+                var abName = rdr.ReadBytes(4);
+                if (abName.Length != 4)
+                    return null;
+                rhdr.name = Encoding.ASCII.GetString(abName);
+                if (!rdr.TryReadBeUInt16(out rhdr.id))
+                    return null;
+                if (!rdr.TryReadBeUInt32(out rhdr.offset))
+                    return null;
+                headers.Add(rhdr);
+            }
+            return headers;
+        }
+
+        private SegmentMap LoadResources(BeImageReader rdr, List<ResourceHeader> rsrcHeaders, Address addrBase)
+        {
+            var segments = new List<ImageSegment>();
+            var addr = addrBase;
+            for (int i = 0; i < rsrcHeaders.Count - 1;  ++i)
+            {
+                var hdr = rsrcHeaders[i];
+                var length = rsrcHeaders[i+1].offset - hdr.offset;
+                rdr.Offset = hdr.offset;
+                var bytes = rdr.ReadBytes(length);
+                var mem = new ByteMemoryArea(addr, bytes);
+                string? name = hdr.name;
+                if (name is null)
+                    name = $"#{hdr.id}";
+                else
+                    name = $"{name}#{hdr.id}";
+                var accessMode = AccessMode.Read;
+                if (hdr.name == "code")
+                {
+                    if (hdr.id == 0)
+                    {
+                        LoadCode0Resource();
+                    }
+                    else
+                    {
+                        accessMode = AccessMode.ReadExecute;
+                    }
+                }
+                var seg = new ImageSegment(name, mem, accessMode);
+                segments.Add(seg);
+                addr += length; //$TODO: align to even paragraph boundary?
+            }
+            return new SegmentMap(segments.ToArray());
+        }
+
+        private void LoadCode0Resource()
+        {
+            //$TODO: according to the doc page, the code0 resource sometimes
+            // is patterend after MacOS, with a jump table above the "a5 line",
+            // and sometimes follows a different convention. Needs more investigation,
+            // and access to different binaries build by different toolchains.
+        }
+    }
+}

src/Environments/PalmOS/PRC/ResourceHeader.cs

@@ -0,0 +1,35 @@
+#region License
+/* 
+ * Copyright (C) 1999-2023 John Källén.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Reko.Environments.PalmOS.PRC
+{
+    public class ResourceHeader
+    {
+        public string? name;
+        public ushort id;
+        public uint offset;
+    }
+}

src/Environments/PalmOS/PalmOS.csproj

@@ -0,0 +1,16 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <Import Project="$(ProjectDir)../../Drivers/CommonBuildProperties.items" />
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <OutputType>Library</OutputType>
+    <RootNamespace>Reko.Environments.PalmOS</RootNamespace>
+    <AssemblyName>Reko.Environments.PalmOS</AssemblyName>
+    <Nullable>enable</Nullable>
+    <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
+    <Configurations>Debug;Release</Configurations>
+  </PropertyGroup>
+	<ItemGroup>
+		<ProjectReference Include="..\..\Arch\M68k\M68k.csproj" />
+		<ProjectReference Include="..\..\Core\Core.csproj" />
+	</ItemGroup>
+</Project>