Add support for passing the string length as argument

Author: twistedfall

binding-generator/src/settings/argument_override.rs

@@ -169,6 +169,13 @@ fn core_arg_override_factory() -> ArgOverride {
 				HashMap::from([("allocator", TypeRefTypeHint::ExplicitLifetime(Lifetime::statik()))]),
 			)],
 		),
+		(
+			"cv::ocl::convertTypeStr",
+			vec![(
+				pred!(mut, ["sdepth", "ddepth", "cn", "buf", "buf_size"]),
+				HashMap::from([("buf", TypeRefTypeHint::StringWithLen("buf_size".into()))]),
+			)],
+		),
 	]))
 }
 

binding-generator/src/type_ref/types.rs

@@ -1,5 +1,6 @@
 use std::borrow::Cow;
 use std::fmt;
+use std::rc::Rc;
 use std::sync::Arc;
 
 use clang::Type;
@@ -20,6 +21,8 @@ pub enum TypeRefTypeHint {
 	LenForSlice(Arc<[String]>, usize),
 	/// Treat C++ string as a byte buffer (`Vec<u8>`) instead of an actual string, argument is optional cpp_arg_name of the argument that specifies the buffer byte length
 	StringAsBytes(Option<Arc<str>>),
+	/// String len is passed in an additional argument (cpp_arg_name)
+	StringWithLen(Rc<str>),
 	/// when C++ char needs to be represented as Rust char
 	CharAsRustChar,
 	/// for the cases when `char *` should not be treated as string, but as a pointer to single char
@@ -57,6 +60,7 @@ impl TypeRefTypeHint {
 			| Self::Slice
 			| Self::LenForSlice(_, _)
 			| Self::StringAsBytes(_)
+			| Self::StringWithLen(_)
 			| Self::CharAsRustChar
 			| Self::CharPtrSingleChar
 			| Self::PrimitivePtrAsRaw
@@ -74,6 +78,7 @@ impl TypeRefTypeHint {
 			| Self::Slice
 			| Self::LenForSlice(_, _)
 			| Self::StringAsBytes(_)
+			| Self::StringWithLen(_)
 			| Self::CharAsRustChar
 			| Self::CharPtrSingleChar
 			| Self::PrimitivePtrAsRaw

binding-generator/src/writer/rust_native/type_ref/render_lane/string.rs

@@ -108,14 +108,22 @@ impl RenderLaneTrait for OutStringRenderLane<'_, '_> {
 			StrType::StdString(_) => format!("std::string {name}_out"),
 			StrType::CvString(_) => format!("cv::String {name}_out"),
 			StrType::CharPtr(str_enc) => {
-				let len = if matches!(str_enc, StrEnc::Binary) {
-					if let TypeRefTypeHint::StringAsBytes(Some(len_arg_name)) = self.canonical.type_hint() {
-						len_arg_name.as_ref()
-					} else {
-						"1024"
-					}
-				} else {
-					"1024"
+				let len = match self.canonical.type_hint() {
+					TypeRefTypeHint::StringAsBytes(Some(len_arg_name)) if matches!(str_enc, StrEnc::Binary) => len_arg_name.as_ref(),
+					TypeRefTypeHint::StringWithLen(len_arg_name) => len_arg_name.as_ref(),
+					TypeRefTypeHint::None
+					| TypeRefTypeHint::Nullable
+					| TypeRefTypeHint::NullableSlice
+					| TypeRefTypeHint::Slice
+					| TypeRefTypeHint::LenForSlice(_, _)
+					| TypeRefTypeHint::StringAsBytes(_)
+					| TypeRefTypeHint::CharAsRustChar
+					| TypeRefTypeHint::CharPtrSingleChar
+					| TypeRefTypeHint::PrimitivePtrAsRaw
+					| TypeRefTypeHint::AddArrayLength(_)
+					| TypeRefTypeHint::BoxedAsRef(_, _, _)
+					| TypeRefTypeHint::TraitClassConcrete
+					| TypeRefTypeHint::ExplicitLifetime(_) => "1024",
 				};
 				format!("std::unique_ptr<char[]> {name}_out = std::make_unique<char[]>({len})")
 			}