api: move verbatim c code out of gendispatch.lua and into c files

Remove max_fname_len check, which caused false successful lookups,
and was an optimization for a very rare case.

src/nvim/CMakeLists.txt

@@ -18,7 +18,8 @@ set(API_METADATA ${PROJECT_BINARY_DIR}/api_metadata.mpack)
 set(FUNCS_DATA ${PROJECT_BINARY_DIR}/funcs_data.mpack)
 set(HEADER_GENERATOR ${PROJECT_SOURCE_DIR}/scripts/gendeclarations.lua)
 set(GENERATED_INCLUDES_DIR ${PROJECT_BINARY_DIR}/include)
-set(GENERATED_API_DISPATCH ${GENERATED_DIR}/api/private/dispatch.c)
+set(GENERATED_API_DISPATCH ${GENERATED_DIR}/api/private/dispatch_wrappers.generated.h)
+set(GENERATED_FUNCS_METADATA ${GENERATED_DIR}/api/private/funcs_metadata.generated.h)
 set(GENERATED_EX_CMDS_ENUM ${GENERATED_INCLUDES_DIR}/ex_cmds_enum.generated.h)
 set(GENERATED_EX_CMDS_DEFS ${GENERATED_DIR}/ex_cmds_defs.generated.h)
 set(GENERATED_FUNCS_HASH_INPUT ${GENERATED_DIR}/funcs.generated.h.gperf)
@@ -197,8 +198,11 @@ add_custom_command(OUTPUT ${GENERATED_UNICODE_TABLES}
     ${UNICODE_FILES}
 )
 
-add_custom_command(OUTPUT ${GENERATED_API_DISPATCH} ${API_METADATA}
-    COMMAND ${LUA_PRG} ${DISPATCH_GENERATOR} ${CMAKE_CURRENT_LIST_DIR} ${API_HEADERS} ${GENERATED_API_DISPATCH} ${API_METADATA}
+add_custom_command(OUTPUT ${GENERATED_API_DISPATCH} ${GENERATED_FUNCS_METADATA}
+                          ${API_METADATA}
+  COMMAND ${LUA_PRG} ${DISPATCH_GENERATOR} ${CMAKE_CURRENT_LIST_DIR}
+                     ${API_HEADERS} ${GENERATED_API_DISPATCH}
+                     ${GENERATED_FUNCS_METADATA} ${API_METADATA}
   DEPENDS
     ${API_HEADERS}
     ${MSGPACK_RPC_HEADERS}

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

src/nvim/api/private/dispatch.h

@@ -18,6 +18,7 @@ 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

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;