[feature request] Support `std::shared_ptr` (and complete Github Actions workflow example file with generating bindings of popular libraries)

[vadimkantorov]

UPD: the missing std::shared_ptr<T> support context is in the message #1860 (comment). Currently this support seems missing, and shared_ptr/unique_ptr are quite common types in modern C++ APIs to be processed

JavaCpp seems to support binding std::shared_ptr<T>: bytedeco/javacpp#623

Below is a very long thread where we ended up rolling a fully complete GitHub Actions Workflow file.

---

GitHub Actions allow for a reproducible environment, so pulling in-tree a collection of GitHub Actions workflow files for popular libraries from https://github.com/mono/CppSharp?tab=readme-ov-file#users (like ffmpeg or dearimgui) could be a great start for new users showcasing the install procedures.

And sometimes it would be possible to just copy the filly self-contained workflow-file and modify it to create a command for binding-generation for a new library. Then users could send PRs with such workflows/scripts, and they could be tested easily (and especially - tested against new versions of the libraries). Currently https://github.com/mono/CppSharp/tree/main/tests doesn't have many real-world library examples.

I found https://github.com/mono/CppSharp/blob/main/.github/workflows/main.yml. Could it be considered a base for such a workflow file producing a fully functioning llvm+CppSharp install?

[vadimkantorov]

I wrote down a primer of a minimalistic workflow file I meant above, looking to generate C API bindings to https://github.com/triton-inference-server/core/blob/main/include/triton/core/tritonserver.h

Does CppSharp absolutely need to have access to CppSharp compiled libtritonserver.so? (module.LibraryDirs / module.Libraries)

How could

name: tritonservercppsharp

on: workflow_dispatch

env:
  PLATFORM: x64

jobs:
  tritonservercppsharp:
    runs-on: ubuntu-22.04
    steps:
      - uses: actions/checkout@v2

      - name: Write down the bindings code
        run: |
          tee tritonservercppsharp.cs <<EOF
            namespace CppSharpTransformer { class DllDemoGenerator : CppSharp.ILibrary {
                public static void Main(string[] args) { CppSharp.ConsoleDriver.Run(new DllDemoGenerator()); }
                public void SetupPasses(CppSharp.Driver driver) { }
                public void Preprocess(CppSharp.Driver driver, ASTContext ctx) { }
                public void Postprocess(CppSharp.Driver driver, ASTContext ctx) { }
                void ILibrary.Setup(CppSharp.Driver driver) { }
                void Setup(CppSharp.Driver driver) {
                    var options = driver.Options;
                    options.GeneratorKind = GeneratorKind.CSharp;
                    var module = options.AddModule("TritonServerCppSharp");
                    module.IncludeDirs.Add("core/include");
                    module.Headers.Add("triton/core/tritonserver.h");
                    //module.LibraryDirs.Add("/path/to/triton/which/containslibtritonserver.so/");
                    //module.Libraries.Add("libtritonserver.so");
                }
            } }
          EOF

      - name: Clone and build CppSharp
        run: |
          #wget https://dot.net/v1/dotnet-install.sh && bash dotnet-install.sh --channel 9.0
          git clone --single-branch --depth 1 --branch v1.1 https://github.com/mono/CppSharp
          cd CppSharp
          bash build/build.sh generate -configuration Release -platform $PLATFORM
          bash build/build.sh download_llvm -platform $PLATFORM
          bash build/build.sh restore -platform $PLATFORM
          bash build/build.sh -platform $PLATFORM -build_only
          find bin
          dotnet --version

      - name: Generating bindings
        run: |
          git clone --single-branch --depth 1 --branch r23.03 https://github.com/triton-inference-server/core
          #"$HOME/.dotnet"
          DOTNET_ROOT=/usr/share/dotnet
          DOTNETSDKVER=$(dotnet --version)
          DOTNETFWKVER=$(dotnet --list-runtimes | grep Microsoft.NETCore.App | tail -n 1 | cut -d " " -f2)
          DOTNETLIBDIR="$DOTNET_ROOT/shared/Microsoft.NETCore.App/$DOTNETFWKVER"
          LD_LIBRARY_PATH=CppSharp/bin/Release_x64/ dotnet "$DOTNET_ROOT/sdk/$DOTNETSDKVER/Roslyn/bincore/csc.dll" -r:CppSharp/bin/Release_x64/CppSharp.dll -r:CppSharp/bin/Release_x64/CppSharp.AST.dll -r:CppSharp/bin/Release_x64/CppSharp.Parser.dll $(find "$DOTNETLIBDIR" -name "*.dll" -printf '-r:"%p" ')  -target:library -out:tritonservercppsharp.exe tritonservercppsharp.cs
          dotnet tritonservercppsharp.exe


#      - uses: actions/upload-artifact@v4
#        with:
#          path: CppSharp/bin/Release_x64/

[tritao]

Could it be considered a base for such a workflow file producing a fully functioning llvm+CppSharp install?

Sure, though this way will compile CppSharp from source (which I personally like, though takes a bit more time).
Another valid approach would be to re-use the Nuget packages published by CppSharp's own CI step.

Does CppSharp absolutely need to have access to CppSharp compiled libtritonserver.so? (module.LibraryDirs / module.Libraries)

IIRC it does not need it, it's only used to find which symbols are provided by the compiled libraries. Especially for C libraries this is not a concern, because header-only inline symbols are usually not present. For C++, it might be a concern depending on the library.

Also to note, for some applications, the CppSharp CLI might be useful since it does not need a custom C# code setup: https://github.com/mono/CppSharp/blob/main/src/CLI/CLI.cs

Customization is harder in that case, but does not have to be the case. I would be very helpful to provide a declarative customization model for simple cases (YAML or even C# script based).

[vadimkantorov]

Also to note, for some applications, the CppSharp CLI might be useful since it does not need a custom C# code setup

Is there an example of using this tool anywhere? For simple things (and as a baseline), it should indeed be sufficient! I think it's worth advertising a complete example of using this option in the CppSharp's README directly (to have a complete example with dotnet add package and dotnet tool ... or similar) :)

Another valid approach would be to re-use the Nuget packages published by CppSharp's own CI step.

For this case, do I need to do dotnet add package CppSharp? And in both cases, which assemblies do I need to reference for csc.dll to get the basic CppSharp.ILibrary and CppSharp.Driver?

Thanks!

[tritao]

Is there an example of using this tool anywhere? For simple things (and as a baseline), it should indeed be sufficient!

The test suite is using it, but I would check out the CLI tool directly, as it provides help and description for the parameters:
https://github.com/mono/CppSharp/blob/main/tests/napi/test.sh#L13

For this case, do I need to do dotnet add package CppSharp? And in both cases, which assemblies do I need to reference for csc.dll to get the basic CppSharp.ILibrary and CppSharp.Driver?

I think these are the main ones:

• CppSharp
• CppSharp.AST
• CppSharp.Generator
• CppSharp.Parser
• CppSharp.Parser.CppSharp

I am not the best person to ask about Nuget as I rarely use it in my workflows.

But development versions are pushed to GitHub packages:

          dotnet nuget push "*.nupkg" --api-key ${{ secrets.GITHUB_TOKEN }} --source "https://nuget.pkg.github.com/mono/index.json" --skip-duplicate

https://github.com/mono/CppSharp/pkgs/nuget/CppSharp

The last version says it was published 4 months ago, so maybe publishing for ongoing development commits is not working correctly after all.

[vadimkantorov]

For some reason I'm getting problems loading the generated exe (depsite that I copy all the .dlls and .sos in the current dir:

Unhandled exception. System.IO.FileNotFoundException: Could not load file or assembly 'CppSharp.Generator, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.

File name: 'CppSharp.Generator, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'
/home/runner/work/_temp/388ed1a4-2143-4a23-bfad-d50c5b136892.sh: line 25:  2764 Aborted                 (core dumped) dotnet 

name: tritonservercppsharp

on: workflow_dispatch

env:
  PLATFORM: x64

jobs:
  tritonservercppsharp:
    runs-on: ubuntu-22.04
    steps:
      - uses: actions/checkout@v2

      - name: Write down the bindings code
        run: |
          tee tritonservercppsharp.cs <<EOF
              namespace CppSharpTransformer { public class DllDemoGenerator : CppSharp.ILibrary {
              public static void Main(string[] args) { CppSharp.ConsoleDriver.Run(new DllDemoGenerator()); }
              public void SetupPasses(CppSharp.Driver driver) { }
              public void Preprocess(CppSharp.Driver driver, CppSharp.AST.ASTContext ctx) { }
              public void Postprocess(CppSharp.Driver driver, CppSharp.AST.ASTContext ctx) { }
              public void Setup(CppSharp.Driver driver) {
              var options = driver.Options;
              options.GeneratorKind = CppSharp.Generators.GeneratorKind.CSharp;
              var module = options.AddModule("TritonServerCppSharp");
              module.IncludeDirs.Add("core/include");
              module.Headers.Add("triton/core/tritonserver.h");
              module.Headers.Add("triton/core/tritonbackend.h");
              module.Headers.Add("triton/core/tritoncache.h");
              module.Headers.Add("triton/core/tritonrepoagent.h");
              //module.LibraryDirs.Add("/path/to/triton/server.so");
              //module.Libraries.Add("tritonserver.so");
              } } }
          EOF

      - name: Clone and build CppSharp
        run: |
          #wget https://dot.net/v1/dotnet-install.sh && bash dotnet-install.sh --channel 9.0
          git clone --single-branch --depth 1 https://github.com/mono/CppSharp
          cd CppSharp
          bash build/build.sh generate -configuration Release -platform $PLATFORM
          bash build/build.sh download_llvm -platform $PLATFORM
          bash build/build.sh restore -platform $PLATFORM
          bash build/build.sh -platform $PLATFORM -build_only
          find bin

      - name: Generating bindings
        run: |
          git clone --single-branch --depth 1 https://github.com/triton-inference-server/core
          #"$HOME/.dotnet"
          DOTNET_ROOT=/usr/share/dotnet
          DOTNETSDKVER=$(dotnet --version)
          DOTNETFWKVER=$(dotnet --list-runtimes | grep Microsoft.NETCore.App | tail -n 1 | cut -d " " -f2)
          DOTNETLIBDIR="$DOTNET_ROOT/shared/Microsoft.NETCore.App/$DOTNETFWKVER"
          dotnet --version
          dotnet --list-runtimes
          echo $DOTNETSDKVER $DOTNETFWKVER
          # -r:CppSharp/bin/Release_x64/CppSharp.dll -r:CppSharp/bin/Release_x64/CppSharp.AST.dll -r:CppSharp/bin/Release_x64/CppSharp.Parser.dll

          #echo 'namespace ProgramNamespace { public static class Program { public static void Main(string[] args) { System.Console.WriteLine("Hello world!"); } } }' > footest.cs
          #dotnet "$DOTNET_ROOT/sdk/$DOTNETSDKVER/Roslyn/bincore/csc.dll" $(find "$DOTNETLIBDIR" -name "*.dll" -printf '-r:"%p" ') -target:exe -out:footest.exe footest.cs
          #echo '{"runtimeOptions":{"framework":{"name":"Microsoft.NETCore.App","version":"'$DOTNETFWKVER'"}}}' > footest.runtimeconfig.json
          #dotnet footest.exe

          find CppSharp/bin/Release_x64 -name 'CppSharp*.dll'
          # -r:CppSharp/bin/Release_x64/CppSharp.dll -r:CppSharp/bin/Release_x64/CppSharp.AST.dll -r:CppSharp/bin/Release_x64/CppSharp.Runtime.dll -r:CppSharp/bin/Release_x64/CppSharp.CLI.dll -r:CppSharp/bin/Release_x64/CppSharp.Parser.dll -r:CppSharp/bin/Release_x64/CppSharp.Parser.CSharp.dll -r:CppSharp/bin/Release_x64/CppSharp.Parser.Bootstrap.dll -r:CppSharp/bin/Release_x64/CppSharp.Parser.Gen.dll

          dotnet "$DOTNET_ROOT/sdk/$DOTNETSDKVER/Roslyn/bincore/csc.dll" $(find "$DOTNETLIBDIR" -name "*.dll" -printf '-r:"%p" ') $(find CppSharp/bin -name "*.dll" -printf '-r:"%p" ') -target:exe -out:tritonservercppsharp.exe tritonservercppsharp.cs
          echo '{"runtimeOptions":{"framework":{"name":"Microsoft.NETCore.App","version":"'$DOTNETFWKVER'"}}}' > tritonservercppsharp.runtimeconfig.json
          echo BEFORE
          find CppSharp/bin -name "*.dll" -o -name "*.so" -exec cp {} . ';'
          dotnet tritonservercppsharp.exe

[tritao]

Have you tried this locally or are you running only on CI?

[vadimkantorov]

Only on CI. It appears that dotnet does not like the libSystem.Native.so which is found successfully on system path and so it proceeds checking the local directory, it cannot find it and then aborts (after loading 10 various unicode libraries to maybe localize the error message :) ):

2024-08-19T17:11:59.5137891Z [pid  2844] openat(AT_FDCWD, "/home/runner/work/tritonservercppsharp/tritonservercppsharp/libSystem.Native.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
2024-08-19T17:11:59.5140546Z [pid  2844] openat(AT_FDCWD, "/usr/share/dotnet/shared/Microsoft.NETCore.App/8.0.7/libSystem.Native.so", O_RDONLY|O_CLOEXEC) = 15
2024-08-19T17:11:59.5142439Z [pid  2844] read(15, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0\0\0\0\0\0\0\0"..., 832) = 832
2024-08-19T17:11:59.5144051Z [pid  2844] newfstatat(15, "", {st_mode=S_IFREG|0777, st_size=90488, ...}, AT_EMPTY_PATH) = 0
2024-08-19T17:11:59.5145178Z [pid  2844] close(15)                   = 0
2024-08-19T17:11:59.5146687Z [pid  2844] access("", F_OK)            = -1 ENOENT (No such file or directory)
2024-08-19T17:11:59.5148223Z [pid  2844] access("opt/corebreadcrumbs", F_OK) = -1 ENOENT (No such file or directory)
2024-08-19T17:11:59.5149673Z [pid  2844] readlink("/home", 0x7fff9273a7e0, 1023) = -1 EINVAL (Invalid argument)
2024-08-19T17:11:59.5151334Z [pid  2844] readlink("/home/runner", 0x7fff9273a7e0, 1023) = -1 EINVAL (Invalid argument)
2024-08-19T17:11:59.5152984Z [pid  2844] readlink("/home/runner/work", 0x7fff9273a7e0, 1023) = -1 EINVAL (Invalid argument)
2024-08-19T17:11:59.5154785Z [pid  2844] readlink("/home/runner/work/tritonservercppsharp", 0x7fff9273a7e0, 1023) = -1 EINVAL (Invalid argument)
2024-08-19T17:11:59.5157228Z [pid  2844] readlink("/home/runner/work/tritonservercppsharp/tritonservercppsharp", 0x7fff9273a7e0, 1023) = -1 EINVAL (Invalid argument)
2024-08-19T17:11:59.5159757Z [pid  2844] stat("/home/runner/work/tritonservercppsharp/tritonservercppsharp/tritonservercppsharp.exe", {st_mode=S_IFREG|0644, st_size=4608, ...}) = 0
2024-08-19T17:11:59.5162486Z [pid  2844] openat(AT_FDCWD, "/home/runner/work/tritonservercppsharp/tritonservercppsharp/tritonservercppsharp.exe", O_RDONLY) = 15
2024-08-19T17:11:59.5179454Z [pid  2844] openat(AT_FDCWD, "/proc/self/status", O_RDONLY) = 19
2024-08-19T17:11:59.5180713Z [pid  2844] read(19, "Name:\tdotnet\nUmask:\t0022\nState:\t"..., 2047) = 1442
2024-08-19T17:11:59.5181800Z [pid  2844] close(19)                   = 0
2024-08-19T17:11:59.5240540Z Unhandled exception. [pid  2844] openat(AT_FDCWD, "/home/runner/work/tritonservercppsharp/tritonservercppsharp/libSystem.Native.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
2024-08-19T17:11:59.5242833Z [pid  2844] openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 19

[vadimkantorov]

With the similar command:

 echo 'namespace ProgramNamespace { public static class Program { public static void Main(string[] args) { System.Console.WriteLine("Hello world!"); } } }' > footest.cs
 dotnet "$DOTNET_ROOT/sdk/$DOTNETSDKVER/Roslyn/bincore/csc.dll" $(find "$DOTNETLIBDIR" -name "*.dll" -printf '-r:"%p" ') -target:exe -out:footest.exe footest.cs
 echo '{"runtimeOptions":{"framework":{"name":"Microsoft.NETCore.App","version":"'$DOTNETFWKVER'"}}}' > footest.runtimeconfig.json
dotnet footest.exe

this runs with success

but maybe the problem is that the build command uses a different dotnet / runtime and hence incompat with the runtime I use for running the compiled app?

DOTNET_ROOT=/usr/share/dotnet
          DOTNETSDKVER=$(dotnet --version)
          DOTNETFWKVER=$(dotnet --list-runtimes | grep Microsoft.NETCore.App | tail -n 1 | cut -d " " -f2)
          DOTNETLIBDIR="$DOTNET_ROOT/shared/Microsoft.NETCore.App/$DOTNETFWKVER"
          dotnet --version
          dotnet --list-runtimes
          echo $DOTNETSDKVER $DOTNETFWKVER

2024-08-19T17:11:57.7465811Z 8.0.303
2024-08-19T17:11:57.7524923Z Microsoft.AspNetCore.App 6.0.32 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
2024-08-19T17:11:57.7526906Z Microsoft.AspNetCore.App 7.0.20 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
2024-08-19T17:11:57.7528649Z Microsoft.AspNetCore.App 8.0.7 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
2024-08-19T17:11:57.7531310Z Microsoft.NETCore.App 6.0.32 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
2024-08-19T17:11:57.7532927Z Microsoft.NETCore.App 7.0.20 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
2024-08-19T17:11:57.7534428Z Microsoft.NETCore.App 8.0.7 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
2024-08-19T17:11:57.7535843Z 8.0.303 8.0.7

[tritao]

Seems likely, any reason you are installing a separate .NET version instead of using the system one?

[vadimkantorov]

any reason you are installing a separate .NET version instead of using the system one?

I am not installing any separate .NET. This line is commented out #wget https://dot.net/v1/dotnet-install.sh && bash dotnet-install.sh --channel 9.0. I was not sure if Ubuntu comes with the system one or not

[tritao]

Ok, have you tried without this tritonservercppsharp.runtimeconfig.json? Why are you generating it?

[vadimkantorov]

It appears in CppSharp.Generator.dll the following. So it seems that build script use the 6.0 version of .NET despite that default (and latest) version is 8.0 (as reported by dotnet --version).

{
  "runtimeTarget": {
    "name": ".NETCoreApp,Version=v6.0",
    "signature": ""
  },

[vadimkantorov]

Why are you generating it?

Because otherwise dotnet command cannot run the executables built directly with csc :(

[tritao]

Ok, must be a new .NET feature, previously I don't remember that being necessary.

8cf6e3f

Maybe this can help, you can pass -target-framework to the build script.