Fix C# director dispatcher calls missing 'out' and 'ref' keywords

[Copilot]

C# director method dispatchers were calling delegates without required out/ref keywords, causing compilation errors.

Changes

Source/Modules/csharp.cxx (lines 4320-4332)

• Added logic to detect out/ref modifiers in parameter typemaps
• Modified mono_aot_dispatcher_parms construction to include modifiers
• Checks both im_directorinattributes and imtype typemap for modifier presence
• Handles space and tab separators

Example

Before (compilation error):

private int SwigDirectorMethodRead(IntPtr buf, int len, out int readLen) {
    return delegateSwigDelegateInStream_0(buf, len, readLen);  // Missing 'out'
}

After (correct):

private int SwigDirectorMethodRead(IntPtr buf, int len, out int readLen) {
    return delegateSwigDelegateInStream_0(buf, len, out readLen);
}

Notes

• Affects Mono AOT compatibility mode only
• Existing test coverage in Examples/test-suite/csharp_director_typemaps.i

Original prompt

I'd like to publish the output from the github action to an azure devops universal package, alternatively to an azure blob storage. I'll be using a managed identity. It seems like the windows zip file available on swig's website is just the entire folder

Summary

TITLE: Adding out parameter support to C# director method dispatcher calls in SWIG

USER INTENT: Fix a C# compilation error where out parameters in director methods are not being passed with the out keyword in the generated dispatcher method calls.

TASK DESCRIPTION:
The user is working on SWIG's C# code generator module (csharp.cxx) and encountering a C# compiler error. The generated code for director method dispatchers is missing the out keyword when calling delegates that have out parameters. The error shows that in the SwigDirectorRead_Dispatcher method, the parameter readLen is declared as out int readLen but when calling the delegate, it's being passed as just readLen instead of out readLen.

EXISTING:

• SWIG's C# module generates director code for cross-language callbacks
• The classDirectorMethod function in csharp.cxx generates dispatcher methods
• Around line 4319, the code builds mono_aot_dispatcher_parms string with just parameter names
• The delegate_parms string (line 4317) correctly includes modifiers from im_directorinattributes
• The generated dispatcher signature correctly shows out modifiers

PENDING:

• Ensure the dispatcher method calls include out or ref keywords when invoking delegates with such parameters

CODE STATE:
File: /Users/aw/code/swig/Source/Modules/csharp.cxx

Modified section (lines 4312-4327):

if (i > 0) {
  Printf(delegate_parms, ", ");
  Printf(mono_aot_dispatcher_parms, ", ");
  Printf(proxy_method_types, ", ");
  Printf(imcall_args, ", ");
}
Printf(delegate_parms, "%s%s %s", im_directorinattributes ? im_directorinattributes : empty_string, tm, ln);
// Check if the parameter has out or ref modifier and add it to the dispatcher call
if (im_directorinattributes && (Strstr(im_directorinattributes, "out ") || Strstr(im_directorinattributes, "out\t"))) {
  Printf(mono_aot_dispatcher_parms, "out %s", ln);
} else if (im_directorinattributes && (Strstr(im_directorinattributes, "ref ") || Strstr(im_directorinattributes, "ref\t"))) {
  Printf(mono_aot_dispatcher_parms, "ref %s", ln);
} else {
  Printf(mono_aot_dispatcher_parms, "%s", ln);
}

This change checks the im_directorinattributes (from tmap:imtype:directorinattributes) for out or ref modifiers and includes them when building the mono_aot_dispatcher_parms string, which is later used at line 4435 to create the delegate call.

RELEVANT CODE/DOCUMENTATION SNIPPETS:

Generated C# code flow:

1. Line 4317: Builds delegate_parms with modifiers: "out int readLen"
2. Lines 4319-4327: Builds mono_aot_dispatcher_parms (now with modifiers): "out readLen"
3. Line 4435: Creates upcall_mono_aot: "delegateSwigDelegateInStream_0(buf, len, out readLen)"
4. Line 4447: Inserts into template code that generates the actual dispatcher method

Error before fix:

return delegateSwigDelegateInStream_0(buf, len, readLen);  // Missing 'out' keyword

Expected after fix:

return delegateSwigDelegateInStream_0(buf, len, out readLen);  // Correct

OTHER NOTES:

• The fix handles both out and ref modifiers
• Checks for both space and tab separators after keywords
• The im_directorinattributes comes from the typemap's directorinattributes attribute
• The change only affects mono AOT compatibility mode dispatcher calls
• No compilation errors introduced by the change (only pre-existing Clang-Tidy warnings)

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