commit 40cfb0691e233e164efee27873454cf457255a47
parent 9b7af7e45bfe3432be8fea27e70de076b22f805f
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Tue, 18 Mar 2003 09:25:10 -0300
new auxiliary functions for `type' manipulation
Diffstat:
| M | lauxlib.c | | | 54 | ++++++++++++++++++++++++++++++++++++++++-------------- |
| M | lauxlib.h | | | 11 | +++++++---- |
| M | liolib.c | | | 30 | +++++++++--------------------- |
3 files changed, 56 insertions(+), 39 deletions(-)
diff --git a/lauxlib.c b/lauxlib.c
@@ -1,5 +1,5 @@
/*
-** $Id: lauxlib.c,v 1.94 2003/02/11 09:44:38 roberto Exp roberto $
+** $Id: lauxlib.c,v 1.95 2003/02/11 15:32:31 roberto Exp roberto $
** Auxiliary functions for building Lua libraries
** See Copyright Notice in lua.h
*/
@@ -103,6 +103,45 @@ LUALIB_API int luaL_findstring (const char *name, const char *const list[]) {
}
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
+ lua_pushstring(L, tname);
+ lua_rawget(L, LUA_REGISTRYINDEX); /* get registry.name */
+ if (!lua_isnil(L, -1)) /* name already in use? */
+ return 0; /* leave previous value on top, but return 0 */
+ lua_pop(L, 1);
+ lua_newtable(L); /* create metatable */
+ lua_pushstring(L, tname);
+ lua_pushvalue(L, -2);
+ lua_rawset(L, LUA_REGISTRYINDEX); /* registry.name = metatable */
+ lua_pushvalue(L, -1);
+ lua_pushstring(L, tname);
+ lua_rawset(L, LUA_REGISTRYINDEX); /* registry[metatable] = name */
+ return 1;
+}
+
+
+LUALIB_API void luaL_getmetatable (lua_State *L, const char *tname) {
+ lua_pushstring(L, tname);
+ lua_rawget(L, LUA_REGISTRYINDEX);
+}
+
+
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
+ const char *tn;
+ if (!lua_getmetatable(L, ud)) return NULL; /* no metatable? */
+ lua_rawget(L, LUA_REGISTRYINDEX); /* get registry[metatable] */
+ tn = lua_tostring(L, -1);
+ if (tn && (strcmp(tn, tname) == 0)) {
+ lua_pop(L, 1);
+ return lua_touserdata(L, ud);
+ }
+ else {
+ lua_pop(L, 1);
+ return NULL;
+ }
+}
+
+
LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) {
if (!lua_checkstack(L, space))
luaL_error(L, "stack overflow (%s)", mes);
@@ -121,19 +160,6 @@ LUALIB_API void luaL_checkany (lua_State *L, int narg) {
}
-LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
- if (!lua_getmetatable(L, ud)) return NULL; /* no metatable? */
- lua_pushstring(L, tname);
- lua_rawget(L, LUA_REGISTRYINDEX);
- if (!lua_rawequal(L, -1, -2)) {
- lua_pop(L, 2);
- return NULL;
- }
- lua_pop(L, 2);
- return lua_touserdata(L, ud);
-}
-
-
LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
const char *s = lua_tostring(L, narg);
if (!s) tag_error(L, narg, LUA_TSTRING);
diff --git a/lauxlib.h b/lauxlib.h
@@ -1,5 +1,5 @@
/*
-** $Id: lauxlib.h,v 1.57 2003/01/27 13:46:16 roberto Exp roberto $
+** $Id: lauxlib.h,v 1.58 2003/02/11 15:32:31 roberto Exp roberto $
** Auxiliary functions for building Lua libraries
** See Copyright Notice in lua.h
*/
@@ -16,7 +16,7 @@
#ifndef LUALIB_API
-#define LUALIB_API extern
+#define LUALIB_API LUA_API
#endif
@@ -33,7 +33,6 @@ LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *e);
LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *e);
LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname);
LUALIB_API int luaL_argerror (lua_State *L, int numarg, const char *extramsg);
-LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname);
LUALIB_API const char *luaL_checklstring (lua_State *L, int numArg, size_t *l);
LUALIB_API const char *luaL_optlstring (lua_State *L, int numArg,
const char *def, size_t *l);
@@ -44,6 +43,10 @@ LUALIB_API void luaL_checkstack (lua_State *L, int sz, const char *msg);
LUALIB_API void luaL_checktype (lua_State *L, int narg, int t);
LUALIB_API void luaL_checkany (lua_State *L, int narg);
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname);
+LUALIB_API void luaL_getmetatable (lua_State *L, const char *tname);
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname);
+
LUALIB_API void luaL_where (lua_State *L, int lvl);
LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...);
@@ -115,7 +118,7 @@ LUALIB_API void luaL_pushresult (luaL_Buffer *B);
/*
-** Compatibility macros
+** Compatibility macros and functions
*/
LUALIB_API int lua_dofile (lua_State *L, const char *filename);
diff --git a/liolib.c b/liolib.c
@@ -1,5 +1,5 @@
/*
-** $Id: liolib.c,v 2.36 2003/03/14 19:00:16 roberto Exp roberto $
+** $Id: liolib.c,v 2.37 2003/03/14 19:08:11 roberto Exp roberto $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/
@@ -87,21 +87,15 @@ static int pushresult (lua_State *L, int i, const char *filename) {
static FILE **topfile (lua_State *L, int findex) {
- FILE **f = (FILE **)lua_touserdata(L, findex);
- if (f == NULL || !lua_getmetatable(L, findex) ||
- !lua_rawequal(L, -1, lua_upvalueindex(1))) {
- luaL_argerror(L, findex, "bad file");
- }
- lua_pop(L, 1);
+ FILE **f = (FILE **)luaL_checkudata(L, findex, FILEHANDLE);
+ if (f == NULL) luaL_argerror(L, findex, "bad file");
return f;
}
static int io_type (lua_State *L) {
- FILE **f = (FILE **)lua_touserdata(L, 1);
- if (f == NULL || !lua_getmetatable(L, 1) ||
- !lua_rawequal(L, -1, lua_upvalueindex(1)))
- lua_pushnil(L);
+ FILE **f = (FILE **)luaL_checkudata(L, 1, FILEHANDLE);
+ if (f == NULL) lua_pushnil(L);
else if (*f == NULL)
lua_pushliteral(L, "closed file");
else
@@ -127,8 +121,7 @@ static FILE *tofile (lua_State *L, int findex) {
static FILE **newfile (lua_State *L) {
FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
*pf = NULL; /* file handle is currently `closed' */
- lua_pushliteral(L, FILEHANDLE);
- lua_rawget(L, LUA_REGISTRYINDEX);
+ luaL_getmetatable(L, FILEHANDLE);
lua_setmetatable(L, -2);
return pf;
}
@@ -527,15 +520,12 @@ static const luaL_reg flib[] = {
static void createmeta (lua_State *L) {
- lua_pushliteral(L, FILEHANDLE);
- lua_newtable(L); /* push new metatable for file handles */
+ luaL_newmetatable(L, FILEHANDLE); /* create new metatable for file handles */
/* file methods */
lua_pushliteral(L, "__index");
lua_pushvalue(L, -2); /* push metatable */
lua_rawset(L, -3); /* metatable.__index = metatable */
- lua_pushvalue(L, -1); /* push metatable (will be upvalue for library) */
- luaL_openlib(L, NULL, flib, 1);
- lua_rawset(L, LUA_REGISTRYINDEX); /* registry.FILEHANDLE = metatable */
+ luaL_openlib(L, NULL, flib, 0);
}
/* }====================================================== */
@@ -748,10 +738,8 @@ static const luaL_reg syslib[] = {
LUALIB_API int luaopen_io (lua_State *L) {
- createmeta(L);
luaL_openlib(L, LUA_OSLIBNAME, syslib, 0);
- lua_pushliteral(L, FILEHANDLE);
- lua_rawget(L, LUA_REGISTRYINDEX);
+ createmeta(L);
lua_pushvalue(L, -1);
luaL_openlib(L, LUA_IOLIBNAME, iolib, 1);
/* put predefined file handles into `io' table */
