map/msgpack-rpc: Declare/define maps rpc method handlers

The new map type uses `String` instances as keys to avoid unnecessary copying to
zero-terminated buffers.

scripts/msgpack-gen.lua

@@ -93,6 +93,7 @@ output:write([[
 
 #include "nvim/map.h"
 #include "nvim/log.h"
+#include "nvim/vim.h"
 #include "nvim/os/msgpack_rpc.h"
 #include "nvim/os/msgpack_rpc_helpers.h"
 #include "nvim/api/private/helpers.h"
@@ -268,8 +269,6 @@ end
 output:write('\n}\n\n')
 
 output:write([[
-#define min(X, Y) (X < Y ? X : Y)
-
 Object msgpack_rpc_dispatch(uint64_t channel_id,
                             msgpack_object *req,
                             Error *error)

src/nvim/map.c

@@ -1,10 +1,12 @@
 #include <stdlib.h>
 #include <stdbool.h>
+#include <string.h>
 
 #include "nvim/map.h"
 #include "nvim/map_defs.h"
 #include "nvim/vim.h"
 #include "nvim/memory.h"
+#include "nvim/os/msgpack_rpc.h"
 
 #include "nvim/lib/khash.h"
 
@@ -87,7 +89,23 @@
     return rv;                                                                \
   }
 
+static inline khint_t String_hash(String s)
+{
+  khint_t h = 0;
+  for (size_t i = 0; i < s.size && s.data[i]; i++) {
+    h = (h << 5) - h + (uint8_t)s.data[i];
+  }
+  return h;
+}
+
+static inline bool String_eq(String a, String b)
+{
+  return strncmp(a.data, b.data, min(a.size, b.size)) == 0;
+}
+
+
 MAP_IMPL(cstr_t, uint64_t, DEFAULT_INITIALIZER)
 MAP_IMPL(cstr_t, ptr_t, DEFAULT_INITIALIZER)
 MAP_IMPL(ptr_t, ptr_t, DEFAULT_INITIALIZER)
 MAP_IMPL(uint64_t, ptr_t, DEFAULT_INITIALIZER)
+MAP_IMPL(String, rpc_method_handler_fn, DEFAULT_INITIALIZER)

src/nvim/map.h

@@ -4,6 +4,8 @@
 #include <stdbool.h>
 
 #include "nvim/map_defs.h"
+#include "nvim/api/private/defs.h"
+#include "nvim/os/msgpack_rpc.h"
 
 #define MAP_DECLS(T, U)                                                       \
   KHASH_DECLARE(T##_##U##_map, T, U)                                          \
@@ -23,6 +25,7 @@ MAP_DECLS(cstr_t, uint64_t)
 MAP_DECLS(cstr_t, ptr_t)
 MAP_DECLS(ptr_t, ptr_t)
 MAP_DECLS(uint64_t, ptr_t)
+MAP_DECLS(String, rpc_method_handler_fn)
 
 #define map_new(T, U) map_##T##_##U##_new
 #define map_free(T, U) map_##T##_##U##_free

src/nvim/vim.h

@@ -8,6 +8,8 @@
 #ifndef NVIM_VIM_H
 # define NVIM_VIM_H
 
+#define min(X, Y) (X < Y ? X : Y)
+
 #include "nvim/types.h"
 #include "nvim/pos.h"  // for linenr_T, MAXCOL, etc...