4 files changed, 68 insertions, 4 deletions
diff --git a/src/nvim/api/private/defs.h b/src/nvim/api/private/defs.h
index a6710193ff..1d5ecd3071 100644
--- a/src/nvim/api/private/defs.h
+++ b/src/nvim/api/private/defs.h
@@ -33,8 +33,8 @@ typedef enum {
 /// Used as the message ID of notifications.
 #define NO_RESPONSE UINT64_MAX
 
-/// Used as channel_id when the call is local
-#define INVALID_CHANNEL UINT64_MAX
+/// Used as channel_id when the call is local.
+#define INTERNAL_CALL UINT64_MAX
 
 typedef struct {
   ErrorType type;
diff --git a/src/nvim/api/private/dispatch.c b/src/nvim/api/private/dispatch.c
new file mode 100644
index 0000000000..9b3bcc380a
--- /dev/null
+++ b/src/nvim/api/private/dispatch.c
@@ -0,0 +1,45 @@
+#include <inttypes.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <assert.h>
+#include <msgpack.h>
+
+#include "nvim/map.h"
+#include "nvim/log.h"
+#include "nvim/vim.h"
+#include "nvim/msgpack_rpc/helpers.h"
+#include "nvim/api/private/dispatch.h"
+#include "nvim/api/private/helpers.h"
+#include "nvim/api/private/defs.h"
+
+#include "nvim/api/buffer.h"
+#include "nvim/api/tabpage.h"
+#include "nvim/api/ui.h"
+#include "nvim/api/vim.h"
+#include "nvim/api/window.h"
+
+static Map(String, MsgpackRpcRequestHandler) *methods = NULL;
+
+static void msgpack_rpc_add_method_handler(String method,
+                                           MsgpackRpcRequestHandler handler)
+{
+  map_put(String, MsgpackRpcRequestHandler)(methods, method, handler);
+}
+
+MsgpackRpcRequestHandler msgpack_rpc_get_handler_for(const char *name,
+                                                     size_t name_len)
+{
+  String m = { .data = (char *)name, .size = name_len };
+  MsgpackRpcRequestHandler rv =
+    map_get(String, MsgpackRpcRequestHandler)(methods, m);
+
+  if (!rv.fn) {
+    rv.fn = msgpack_rpc_handle_missing_method;
+  }
+
+  return rv;
+}
+
+#ifdef INCLUDE_GENERATED_DECLARATIONS
+#include "api/private/dispatch_wrappers.generated.h"
+#endif
diff --git a/src/nvim/api/private/dispatch.h b/src/nvim/api/private/dispatch.h
index d91456c306..39aabd708a 100644
--- a/src/nvim/api/private/dispatch.h
+++ b/src/nvim/api/private/dispatch.h
@@ -4,7 +4,6 @@
 #include "nvim/api/private/defs.h"
 
 typedef Object (*ApiDispatchWrapper)(uint64_t channel_id,
-                                     uint64_t request_id,
                                      Array args,
                                      Error *error);
 
@@ -18,6 +17,7 @@ typedef struct {
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "api/private/dispatch.h.generated.h"
+# include "api/private/dispatch_wrappers.h.generated.h"
 #endif
 
 #endif  // NVIM_API_PRIVATE_DISPATCH_H
diff --git a/src/nvim/api/private/helpers.c b/src/nvim/api/private/helpers.c
index d80ee7dc67..c0ee735d1a 100644
--- a/src/nvim/api/private/helpers.c
+++ b/src/nvim/api/private/helpers.c
@@ -7,6 +7,7 @@
 #include "nvim/api/private/helpers.h"
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/handle.h"
+#include "nvim/msgpack_rpc/helpers.h"
 #include "nvim/ascii.h"
 #include "nvim/vim.h"
 #include "nvim/buffer.h"
@@ -27,6 +28,7 @@ typedef struct {
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "api/private/helpers.c.generated.h"
+# include "api/private/funcs_metadata.generated.h"
 #endif
 
 /// Start block that may cause vimscript exceptions
@@ -761,7 +763,7 @@ Dictionary api_metadata(void)
   static Dictionary metadata = ARRAY_DICT_INIT;
 
   if (!metadata.size) {
-    msgpack_rpc_init_function_metadata(&metadata);
+    init_function_metadata(&metadata);
     init_error_type_metadata(&metadata);
     init_type_metadata(&metadata);
   }
@@ -769,6 +771,22 @@ Dictionary api_metadata(void)
   return copy_object(DICTIONARY_OBJ(metadata)).data.dictionary;
 }
 
+static void init_function_metadata(Dictionary *metadata)
+{
+  msgpack_unpacked unpacked;
+  msgpack_unpacked_init(&unpacked);
+  if (msgpack_unpack_next(&unpacked,
+                          (const char *)funcs_metadata,
+                          sizeof(funcs_metadata),
+                          NULL) != MSGPACK_UNPACK_SUCCESS) {
+    abort();
+  }
+  Object functions;
+  msgpack_rpc_to_object(&unpacked.data, &functions);
+  msgpack_unpacked_destroy(&unpacked);
+  PUT(*metadata, "functions", functions);
+}
+
 static void init_error_type_metadata(Dictionary *metadata)
 {
   Dictionary types = ARRAY_DICT_INIT;
@@ -784,6 +802,7 @@ static void init_error_type_metadata(Dictionary *metadata)
 
   PUT(*metadata, "error_types", DICTIONARY_OBJ(types));
 }
+
 static void init_type_metadata(Dictionary *metadata)
 {
   Dictionary types = ARRAY_DICT_INIT;