refactor(eval): use Hashy McHashFace instead of gperf

this removes gperf as a build dependency

src/nvim/CMakeLists.txt

@@ -185,15 +185,8 @@ if(NOT MSVC)
   set_source_files_properties(
     ${EXTERNAL_SOURCES} PROPERTIES COMPILE_FLAGS "${COMPILE_FLAGS} -Wno-conversion -Wno-missing-noreturn -Wno-missing-format-attribute -Wno-double-promotion")
 
-  # gperf generates ANSI-C with incorrect linkage, ignore it.
-  check_c_compiler_flag(-Wstatic-in-inline HAS_WSTATIC_IN_INLINE)
-  if(HAS_WSTATIC_IN_INLINE)
-    set_source_files_properties(
-      eval/funcs.c PROPERTIES COMPILE_FLAGS "${COMPILE_FLAGS} -Wno-static-in-inline -Wno-conversion")
-  else()
-    set_source_files_properties(
-      eval/funcs.c PROPERTIES COMPILE_FLAGS "${COMPILE_FLAGS} -Wno-conversion")
-  endif()
+  set_source_files_properties(
+    eval/funcs.c PROPERTIES COMPILE_FLAGS "${COMPILE_FLAGS} -Wno-conversion")
 endif()
 
 if(NOT "${MIN_LOG_LEVEL}" MATCHES "^$")
@@ -408,14 +401,9 @@ add_custom_command(OUTPUT ${GENERATED_EX_CMDS_ENUM} ${GENERATED_EX_CMDS_DEFS}
   DEPENDS ${EX_CMDS_GENERATOR} ${CMAKE_CURRENT_LIST_DIR}/ex_cmds.lua
 )
 
-if(NOT GPERF_PRG)
-  message(FATAL_ERROR "gperf was not found.")
-endif()
 add_custom_command(OUTPUT ${GENERATED_FUNCS} ${FUNCS_DATA}
   COMMAND ${LUA_PRG} ${FUNCS_GENERATOR}
-      ${CMAKE_CURRENT_LIST_DIR} ${GENERATED_DIR} ${API_METADATA} ${FUNCS_DATA}
-  COMMAND ${GPERF_PRG}
-      ${GENERATED_DIR}/funcs.generated.h.gperf --output-file=${GENERATED_FUNCS}
+      ${CMAKE_CURRENT_LIST_DIR} ${LUA_SHARED_MODULE_SOURCE} ${GENERATED_DIR} ${API_METADATA} ${FUNCS_DATA}
   DEPENDS ${FUNCS_GENERATOR} ${CMAKE_CURRENT_LIST_DIR}/eval.lua ${API_METADATA}
 )
 list(APPEND NVIM_GENERATED_FOR_SOURCES

src/nvim/eval/funcs.c

@@ -80,9 +80,6 @@ typedef enum {
   kSomeMatchStrPos,  ///< Data for matchstrpos().
 } SomeMatchType;
 
-KHASH_MAP_INIT_STR(functions, VimLFuncDef)
-
-
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "eval/funcs.c.generated.h"
 
@@ -134,14 +131,11 @@ char_u *get_function_name(expand_T *xp, int idx)
       return name;
     }
   }
-  while ((size_t)++intidx < ARRAY_SIZE(functions)
-         && functions[intidx].name[0] == '\0') {}
 
-  if ((size_t)intidx >= ARRAY_SIZE(functions)) {
+  const char *const key = functions[++intidx].name;
+  if (!key) {
     return NULL;
   }
-
-  const char *const key = functions[intidx].name;
   const size_t key_len = strlen(key);
   memcpy(IObuff, key, key_len);
   IObuff[key_len] = '(';
@@ -178,18 +172,19 @@ char_u *get_expr_name(expand_T *xp, int idx)
 /// @param[in]  name  Name of the function.
 ///
 /// @return  pointer to the function definition or NULL if not found.
-const VimLFuncDef *find_internal_func(const char *const name)
+const EvalFuncDef *find_internal_func(const char *const name)
   FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_PURE FUNC_ATTR_NONNULL_ALL
 {
   size_t len = strlen(name);
-  return find_internal_func_gperf(name, len);
+  int index = find_internal_func_hash(name, len);
+  return index >= 0 ? &functions[index] : NULL;
 }
 
 int call_internal_func(const char_u *const fname, const int argcount, typval_T *const argvars,
                        typval_T *const rettv)
   FUNC_ATTR_NONNULL_ALL
 {
-  const VimLFuncDef *const fdef = find_internal_func((const char *)fname);
+  const EvalFuncDef *const fdef = find_internal_func((const char *)fname);
   if (fdef == NULL) {
     return ERROR_UNKNOWN;
   } else if (argcount < fdef->min_argc) {
@@ -207,7 +202,7 @@ int call_internal_method(const char_u *const fname, const int argcount, typval_T
                          typval_T *const rettv, typval_T *const basetv)
   FUNC_ATTR_NONNULL_ALL
 {
-  const VimLFuncDef *const fdef = find_internal_func((const char *)fname);
+  const EvalFuncDef *const fdef = find_internal_func((const char *)fname);
   if (fdef == NULL) {
     return ERROR_UNKNOWN;
   } else if (fdef->base_arg == BASE_NONE) {

src/nvim/eval/funcs.h

@@ -9,19 +9,19 @@ typedef void (*FunPtr)(void);
 /// Prototype of C function that implements VimL function
 typedef void (*VimLFunc)(typval_T *args, typval_T *rvar, FunPtr data);
 
-/// Special flags for base_arg @see VimLFuncDef
+/// Special flags for base_arg @see EvalFuncDef
 #define BASE_NONE 0          ///< Not a method (no base argument).
 #define BASE_LAST UINT8_MAX  ///< Use the last argument as the method base.
 
 /// Structure holding VimL function definition
-typedef struct fst {
+typedef struct {
   char *name;        ///< Name of the function.
   uint8_t min_argc;  ///< Minimal number of arguments.
   uint8_t max_argc;  ///< Maximal number of arguments.
   uint8_t base_arg;  ///< Method base arg # (1-indexed), BASE_NONE or BASE_LAST.
   VimLFunc func;     ///< Function implementation.
   FunPtr data;       ///< Userdata for function implementation.
-} VimLFuncDef;
+} EvalFuncDef;
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "eval/funcs.h.generated.h"

src/nvim/generators/gen_eval.lua

@@ -1,9 +1,12 @@
 local mpack = require('mpack')
 
 local nvimsrcdir = arg[1]
-local autodir = arg[2]
-local metadata_file = arg[3]
-local funcs_file = arg[4]
+local shared_file = arg[2]
+local autodir = arg[3]
+local metadata_file = arg[4]
+local funcs_file = arg[5]
+
+_G.vim = loadfile(shared_file)()
 
 if nvimsrcdir == '--help' then
   print([[
@@ -20,7 +23,9 @@ package.path = nvimsrcdir .. '/?.lua;' .. package.path
 
 local funcsfname = autodir .. '/funcs.generated.h'
 
-local gperfpipe = io.open(funcsfname .. '.gperf', 'wb')
+local hashy = require'generators.hashy'
+
+local hashpipe = io.open(funcsfname, 'wb')
 
 local funcs = require('eval').funcs
 local metadata = mpack.unpack(io.open(metadata_file, 'rb'):read("*all"))
@@ -38,21 +43,15 @@ local funcsdata = io.open(funcs_file, 'w')
 funcsdata:write(mpack.pack(funcs))
 funcsdata:close()
 
-gperfpipe:write([[
-%language=ANSI-C
-%global-table
-%readonly-tables
-%define initializer-suffix ,0,0,BASE_NONE,NULL,NULL
-%define word-array-name functions
-%define hash-function-name hash_internal_func_gperf
-%define lookup-function-name find_internal_func_gperf
-%omit-struct-type
-%struct-type
-VimLFuncDef;
-%%
-]])
 
-for name, def in pairs(funcs) do
+local names = vim.tbl_keys(funcs)
+
+local neworder, hashfun = hashy.hashy_hash("find_internal_func", names, function (idx)
+  return "functions["..idx.."].name"
+end)
+hashpipe:write("static const EvalFuncDef functions[] = {\n")
+for _, name in ipairs(neworder) do
+  local def = funcs[name]
   local args = def.args or 0
   if type(args) == 'number' then
     args = {args, args}
@@ -62,7 +61,10 @@ for name, def in pairs(funcs) do
   local base = def.base or "BASE_NONE"
   local func = def.func or ('f_' .. name)
   local data = def.data or "NULL"
-  gperfpipe:write(('%s,  %s, %s, %s, &%s, (FunPtr)%s\n')
+  hashpipe:write(('  { "%s", %s, %s, %s, &%s, (FunPtr)%s },\n')
                   :format(name, args[1], args[2], base, func, data))
 end
-gperfpipe:close()
+hashpipe:write('  { NULL, 0, 0, BASE_NONE, NULL, NULL },\n')
+hashpipe:write("};\n\n")
+hashpipe:write(hashfun)
+hashpipe:close()