add csharp_generate_const option

csbindgen/src/builder.rs

@@ -30,6 +30,7 @@ pub struct BindgenOptions {
     pub csharp_if_dll_name: String,
     pub csharp_use_function_pointer: bool,
     pub csharp_imported_namespaces: Vec<String>,
+    pub csharp_generate_const: bool,
 }
 
 impl Default for Builder {
@@ -53,6 +54,7 @@ impl Default for Builder {
                 csharp_if_dll_name: "".to_string(),
                 csharp_use_function_pointer: true,
                 csharp_imported_namespaces: vec![],
+                csharp_generate_const: false,
             },
         }
     }
@@ -181,6 +183,12 @@ impl Builder {
         self
     }
 
+    /// conifure C# generate const, default is false
+    pub fn csharp_generate_const(mut self, csharp_generate_const: bool) -> Builder {
+        self.options.csharp_generate_const = csharp_generate_const;
+        self
+    }
+
     pub fn generate_csharp_file<P: AsRef<Path>>(
         &self,
         csharp_output_path: P,

csbindgen/src/emitter.rs

@@ -79,6 +79,7 @@ pub fn emit_csharp(
     aliases: &AliasMap,
     structs: &Vec<RustStruct>,
     enums: &Vec<RustEnum>,
+    consts: &Vec<RustConst>,
     options: &BindgenOptions,
 ) -> String {
     // configure
@@ -290,6 +291,27 @@ pub fn emit_csharp(
         enum_string.push('\n');
     }
 
+    let mut const_string = String::new();
+    for item in consts {
+        let type_name = item.rust_type.to_csharp_string(
+            options,
+            aliases,
+            false,
+            &"".to_string(),
+            &"".to_string(),
+        );
+
+        const_string.push_str(  
+            format!(
+                "        public {} {} = {};",
+                type_name,
+                escape_name(item.const_name.as_str()),
+                item.value
+            )
+            .as_str(),
+        );
+    }
+
     let mut imported_namespaces = String::new();
     for name in &options.csharp_imported_namespaces {
         imported_namespaces.push_str_ln(format!("using {name};").as_str());
@@ -317,6 +339,7 @@ namespace {namespace}
 
 {structs_string}
 {enum_string}
+{const_string}
 }}
     "
     );

csbindgen/src/lib.rs

@@ -14,7 +14,7 @@ use emitter::*;
 use field_map::FieldMap;
 use parser::*;
 use std::{collections::HashSet, error::Error};
-use type_meta::{ExternMethod, RustEnum, RustStruct, RustType};
+use type_meta::{ExternMethod, RustEnum, RustStruct, RustType, RustConst};
 
 enum GenerateKind {
     InputBindgen,
@@ -34,6 +34,7 @@ pub(crate) fn generate(
     let mut aliases = AliasMap::new();
     let mut structs: Vec<RustStruct> = vec![];
     let mut enums: Vec<RustEnum> = vec![];
+    let mut consts: Vec<RustConst> = vec![];
 
     for path in paths {
         let file_content = std::fs::read_to_string(path)
@@ -47,6 +48,10 @@ pub(crate) fn generate(
         collect_type_alias(&file_ast, &mut aliases);
         collect_struct(&file_ast, &mut structs);
         collect_enum(&file_ast, &mut enums);
+
+        if options.csharp_generate_const {
+            collect_const(&file_ast, &mut consts);
+        }
     }
 
     // collect using_types
@@ -82,7 +87,7 @@ pub(crate) fn generate(
     } else {
         None
     };
-    let csharp = emit_csharp(&methods, &aliases, &structs, &enums, options);
+    let csharp = emit_csharp(&methods, &aliases, &structs, &enums, &consts, options);
 
     Ok((rust, csharp))
 }

csbindgen/src/parser.rs

@@ -11,8 +11,8 @@ enum FnItem {
 /// build a Vec of all Items, unless the Item is a Item::Mod, then append the Item contents of the vect
 /// Do this recursively.
 /// This is not memory-efficient, would work better with an iterator, but does not seem performance critical.
-fn depth_first_module_walk<'a>(ast: &'a Vec<Item>) -> Vec<&'a syn::Item>{
-    let mut unwrapped_items : Vec<&syn::Item> = vec![];
+fn depth_first_module_walk<'a>(ast: &'a Vec<Item>) -> Vec<&'a syn::Item> {
+    let mut unwrapped_items: Vec<&syn::Item> = vec![];
     for item in ast {
         match item {
             Item::Mod(m) => match &m.content {
@@ -232,6 +232,49 @@ fn collect_fields_unnamed(fields: &syn::FieldsUnnamed) -> Vec<FieldMember> {
     result
 }
 
+pub fn collect_const(ast: &syn::File, result: &mut Vec<RustConst>) {
+    for item in depth_first_module_walk(&ast.items) {
+        if let Item::Const(ct) = item {
+            // pub const Ident: ty = expr
+            let const_name = ct.ident.to_string();
+            let t = parse_type(&ct.ty);
+
+            if let syn::Expr::Lit(lit_expr) = &*ct.expr {
+                let value = match &lit_expr.lit {
+                    syn::Lit::Str(s) => {
+                        format!("{}", s.value())
+                    }
+                    syn::Lit::ByteStr(bs) => {
+                        format!("{:?}", bs.value())
+                    }
+                    syn::Lit::Byte(b) => {
+                        format!("{:?}", b.value())
+                    }
+                    syn::Lit::Char(c) => {
+                        format!("'{}'", c.value())
+                    }
+                    syn::Lit::Int(i) => {
+                        format!("{}", i.base10_parse::<i64>().unwrap())
+                    }
+                    syn::Lit::Float(f) => {
+                        format!("{}", f.base10_parse::<f64>().unwrap())
+                    }
+                    syn::Lit::Bool(b) => {
+                        format!("{}", b.value)
+                    }
+                    _ => format!(""),
+                };
+
+                result.push(RustConst {
+                    const_name: const_name,
+                    rust_type: t,
+                    value: value,
+                });
+            }
+        }
+    }
+}
+
 pub fn collect_enum(ast: &syn::File, result: &mut Vec<RustEnum>) {
     for item in depth_first_module_walk(&ast.items) {
         if let Item::Enum(t) = item {

csbindgen/src/type_meta.rs

@@ -101,6 +101,13 @@ pub struct RustEnum {
     pub is_flags: bool,
 }
 
+#[derive(Clone, Debug)]
+pub struct RustConst {
+    pub const_name: String,
+    pub rust_type: RustType,
+    pub value: String,
+}
+
 impl RustType {
     pub fn to_rust_string(&self, type_path: &str) -> String {
         let mut sb = String::new();

dotnet-sandbox/NativeMethods.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace CsBindgen
 {
     internal static unsafe partial class NativeMethods
@@ -247,5 +248,6 @@ namespace CsBindgen
     }
 
 
+
 }
     

dotnet-sandbox/NestedModuleTests.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace CsBindgen
 {
     internal static unsafe partial class NestedModuleTests
@@ -40,5 +41,6 @@ namespace CsBindgen
     }
 
 
+
 }
     

dotnet-sandbox/bullet3_bindgen.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace CsBindgen
 {
     internal static unsafe partial class LibBullet3
@@ -1789,5 +1790,6 @@ namespace CsBindgen
 
 
 
+
 }
     

dotnet-sandbox/libphysx_csbindgen.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace Physx
 {
     internal static unsafe partial class LibPhysx
@@ -11267,5 +11268,6 @@ namespace Physx
     }
 
 
+
 }
     

dotnet-sandbox/libpng16_csbindgen.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace PixivApi.ImageFile
 {
     internal static unsafe partial class LibPng16
@@ -1087,5 +1088,6 @@ namespace PixivApi.ImageFile
 
 
 
+
 }
     

dotnet-sandbox/lz4_bindgen.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace CsBindgen
 {
     public static unsafe partial class LibLz4
@@ -450,5 +451,6 @@ namespace CsBindgen
 
 
 
+
 }
     

dotnet-sandbox/quiche_bindgen.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace CsBindgen
 {
     internal static unsafe partial class LibQuiche
@@ -558,5 +559,6 @@ namespace CsBindgen
 
 
 
+
 }
     

dotnet-sandbox/zstd_bindgen.cs

@@ -7,6 +7,7 @@
 using System;
 using System.Runtime.InteropServices;
 
+
 namespace CsBindgen
 {
     internal static unsafe partial class LibZstd
@@ -306,5 +307,6 @@ namespace CsBindgen
 
 
 
+
 }