Merge pull request #638 from DenisBiryukov91/fix-z_closure-signature

Fix C++ z_closure signature to accept extern "C" function pointers

build.rs

@@ -1619,6 +1619,7 @@ pub fn generate_generic_recv_cpp(macro_func: &[FunctionSignature]) -> String {
 pub fn generate_generic_closure_cpp(macro_func: &[FunctionSignature]) -> String {
     let mut out = "".to_owned();
 
+    out += "extern \"C\" using z_closure_drop_callback_t = void(void*);\n";
     for func in macro_func {
         let return_type = &func.return_type.typename;
         let closure_name = &func.args[0].name;
@@ -1629,12 +1630,20 @@ pub fn generate_generic_closure_cpp(macro_func: &[FunctionSignature]) -> String
             .typename
             .replace("loaned", "owned");
         let arg_type = &func.args[1].typename.typename;
+        let callback_type = func.args[0]
+            .typename
+            .clone()
+            .decay()
+            .typename
+            .replace("_t", "_callback_t")
+            .replace("_loaned", "");
         out += "\n";
         out += &format!(
-            "inline void z_closure(
+            "extern \"C\" using {callback_type} = {return_type}({arg_type}, void*);
+inline void z_closure(
     {closure_type} {closure_name},
-    {return_type} (*call)({arg_type}, void*),
-    void (*drop)(void*),
+    {callback_type}* call,
+    z_closure_drop_callback_t* drop,
     void *context) {{
     {closure_name}->context = context;
     {closure_name}->drop = drop;

include/zenoh_macros.h

@@ -657,38 +657,43 @@ inline void z_call(const z_loaned_closure_sample_t* closure, const z_loaned_samp
     z_closure_sample_call(closure, sample);
 };
 
+extern "C" typedef void (*z_closure_drop_callback_t)(void*);
 
+extern "C" typedef void (*z_closure_hello_callback_t)(const z_loaned_hello_t*, void*);
 inline void z_closure(
     z_owned_closure_hello_t* closure,
-    void (*call)(const z_loaned_hello_t*, void*),
-    void (*drop)(void*),
+    z_closure_hello_callback_t call,
+    z_closure_drop_callback_t drop,
     void *context) {
     closure->context = context;
     closure->drop = drop;
     closure->call = call;
 };
+extern "C" typedef void (*z_closure_query_callback_t)(const z_loaned_query_t*, void*);
 inline void z_closure(
     z_owned_closure_query_t* closure,
-    void (*call)(const z_loaned_query_t*, void*),
-    void (*drop)(void*),
+    z_closure_query_callback_t call,
+    z_closure_drop_callback_t drop,
     void *context) {
     closure->context = context;
     closure->drop = drop;
     closure->call = call;
 };
+extern "C" typedef void (*z_closure_reply_callback_t)(const z_loaned_reply_t*, void*);
 inline void z_closure(
     z_owned_closure_reply_t* closure,
-    void (*call)(const z_loaned_reply_t*, void*),
-    void (*drop)(void*),
+    z_closure_reply_callback_t call,
+    z_closure_drop_callback_t drop,
     void *context) {
     closure->context = context;
     closure->drop = drop;
     closure->call = call;
 };
+extern "C" typedef void (*z_closure_sample_callback_t)(const z_loaned_sample_t*, void*);
 inline void z_closure(
     z_owned_closure_sample_t* closure,
-    void (*call)(const z_loaned_sample_t*, void*),
-    void (*drop)(void*),
+    z_closure_sample_callback_t call,
+    z_closure_drop_callback_t drop,
     void *context) {
     closure->context = context;
     closure->drop = drop;