avoid using function environments in C libraries (as it probably will

be deprecated)
This commit is contained in:
Roberto Ierusalimschy 2010-03-17 18:37:37 -03:00
parent 22ef84b6c8
commit 1514e49d43
4 changed files with 69 additions and 51 deletions

View File

@ -1,5 +1,5 @@
/*
** $Id: lauxlib.c,v 1.201 2010/02/18 19:37:57 roberto Exp roberto $
** $Id: lauxlib.c,v 1.202 2010/03/12 18:59:32 roberto Exp roberto $
** Auxiliary functions for building Lua libraries
** See Copyright Notice in lua.h
*/
@ -670,13 +670,13 @@ LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
static int libsize (const luaL_Reg *l) {
int size = 0;
for (; l->name; l++) size++;
for (; l && l->name; l++) size++;
return size;
}
LUALIB_API void luaL_register (lua_State *L, const char *libname,
const luaL_Reg *l) {
LUALIB_API void luaL_openlib (lua_State *L, const char *libname,
const luaL_Reg *l, int nup) {
luaL_checkversion(L);
if (libname) {
/* check whether lib already exists */
@ -692,12 +692,17 @@ LUALIB_API void luaL_register (lua_State *L, const char *libname,
lua_setfield(L, -3, libname); /* _LOADED[libname] = new table */
}
lua_remove(L, -2); /* remove _LOADED table */
lua_insert(L, -(nup + 1)); /* move library table to below upvalues */
}
if (l == NULL) return; /* nothing to register? */
for (; l->name; l++) { /* else fill the table with given functions */
lua_pushcfunction(L, l->func);
lua_setfield(L, -2, l->name);
luaL_checkstack(L, nup, "too many upvalues");
for (; l && l->name; l++) { /* else fill the table with given functions */
int i;
for (i = 0; i < nup; i++) /* copy upvalues to the top */
lua_pushvalue(L, -nup);
lua_pushcclosure(L, l->func, nup);
lua_setfield(L, -(nup + 2), l->name);
}
lua_pop(L, nup); /* remove upvalues */
}

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@ -1,5 +1,5 @@
/*
** $Id: lauxlib.h,v 1.99 2010/01/11 16:00:45 roberto Exp roberto $
** $Id: lauxlib.h,v 1.100 2010/01/21 16:49:21 roberto Exp roberto $
** Auxiliary functions for building Lua libraries
** See Copyright Notice in lua.h
*/
@ -29,8 +29,8 @@ typedef struct luaL_Reg {
LUALIB_API void (luaL_checkversion_) (lua_State *L, lua_Number ver);
#define luaL_checkversion(L) luaL_checkversion_(L, LUA_VERSION_NUM)
LUALIB_API void (luaL_register) (lua_State *L, const char *libname,
const luaL_Reg *l);
LUALIB_API void (luaL_openlib) (lua_State *L, const char *libname,
const luaL_Reg *l, int nup);
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 const char *luaL_tolstring (lua_State *L, int idx, size_t *len);
@ -71,7 +71,7 @@ LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s);
LUALIB_API lua_State *(luaL_newstate) (void);
LUALIB_API int luaL_len (lua_State *L, int idx);
LUALIB_API int (luaL_len) (lua_State *L, int idx);
LUALIB_API const char *(luaL_gsub) (lua_State *L, const char *s, const char *p,
const char *r);
@ -79,11 +79,11 @@ LUALIB_API const char *(luaL_gsub) (lua_State *L, const char *s, const char *p,
LUALIB_API const char *(luaL_findtable) (lua_State *L, int idx,
const char *fname, int szhint);
LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1,
const char *msg, int level);
LUALIB_API void (luaL_traceback) (lua_State *L, lua_State *L1,
const char *msg, int level);
LUALIB_API int luaL_cpcall (lua_State *L, lua_CFunction f, int nargs,
int nresults);
LUALIB_API int (luaL_cpcall) (lua_State *L, lua_CFunction f, int nargs,
int nresults);
/*
@ -113,6 +113,9 @@ LUALIB_API int luaL_cpcall (lua_State *L, lua_CFunction f, int nargs,
#define luaL_opt(L,f,n,d) (lua_isnoneornil(L,(n)) ? (d) : f(L,(n)))
#define luaL_register(L,n,l) (luaL_openlib(L,(n),(l),0))
/*
** {======================================================
** Generic Buffer manipulation

View File

@ -1,5 +1,5 @@
/*
** $Id: liolib.c,v 2.85 2009/12/17 16:20:01 roberto Exp roberto $
** $Id: liolib.c,v 2.86 2010/03/03 18:48:57 roberto Exp roberto $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/
@ -103,13 +103,12 @@ static FILE *tofile (lua_State *L) {
}
/*
** When creating file handles, always creates a `closed' file handle
** before opening the actual file; so, if there is a memory error, the
** file is not left opened.
*/
static FILE **newfile (lua_State *L) {
static FILE **newprefile (lua_State *L) {
FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
*pf = NULL; /* file handle is currently `closed' */
luaL_getmetatable(L, LUA_FILEHANDLE);
@ -118,6 +117,14 @@ static FILE **newfile (lua_State *L) {
}
static FILE **newfile (lua_State *L) {
FILE **pf = newprefile(L);
lua_pushvalue(L, lua_upvalueindex(1)); /* set upvalue... */
lua_setfenv(L, -2); /* ... as environment for new file */
return pf;
}
/*
** function to (not) close the standard files stdin, stdout, and stderr
*/
@ -164,7 +171,7 @@ static int aux_close (lua_State *L) {
static int io_close (lua_State *L) {
if (lua_isnone(L, 1))
lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT);
lua_rawgeti(L, lua_upvalueindex(1), IO_OUTPUT);
tofile(L); /* make sure argument is a file */
return aux_close(L);
}
@ -229,7 +236,7 @@ static int io_tmpfile (lua_State *L) {
static FILE *getiofile (lua_State *L, int findex) {
FILE *f;
lua_rawgeti(L, LUA_ENVIRONINDEX, findex);
lua_rawgeti(L, lua_upvalueindex(1), findex);
f = *(FILE **)lua_touserdata(L, -1);
if (f == NULL)
luaL_error(L, "standard %s file is closed", fnames[findex - 1]);
@ -250,10 +257,10 @@ static int g_iofile (lua_State *L, int f, const char *mode) {
tofile(L); /* check that it's a valid file handle */
lua_pushvalue(L, 1);
}
lua_rawseti(L, LUA_ENVIRONINDEX, f);
lua_rawseti(L, lua_upvalueindex(1), f);
}
/* return current value */
lua_rawgeti(L, LUA_ENVIRONINDEX, f);
lua_rawgeti(L, lua_upvalueindex(1), f);
return 1;
}
@ -295,7 +302,7 @@ static int io_lines (lua_State *L) {
int toclose;
if (lua_isnone(L, 1)) lua_pushnil(L); /* at least one argument */
if (lua_isnil(L, 1)) { /* no file name? */
lua_rawgeti(L, LUA_ENVIRONINDEX, IO_INPUT); /* get default input */
lua_rawgeti(L, lua_upvalueindex(1), IO_INPUT); /* get default input */
lua_replace(L, 1); /* put it at index 1 */
tofile(L); /* check that it's a valid file handle */
toclose = 0; /* do not close it after iteration */
@ -576,23 +583,27 @@ static void createmeta (lua_State *L) {
luaL_newmetatable(L, LUA_FILEHANDLE); /* create metatable for file handles */
lua_pushvalue(L, -1); /* push metatable */
lua_setfield(L, -2, "__index"); /* metatable.__index = metatable */
luaL_register(L, NULL, flib); /* file methods */
luaL_register(L, NULL, flib); /* add file methods to new metatable */
lua_pop(L, 1); /* pop new metatable */
}
static void createstdfile (lua_State *L, FILE *f, int k, const char *fname) {
*newfile(L) = f;
*newprefile(L) = f;
if (k > 0) {
lua_pushvalue(L, -1);
lua_rawseti(L, LUA_ENVIRONINDEX, k);
lua_pushvalue(L, -1); /* copy new file */
lua_rawseti(L, 1, k); /* add it to common upvalue */
}
lua_pushvalue(L, -2); /* copy environment */
lua_setfenv(L, -2); /* set it */
lua_setfield(L, -3, fname);
lua_pushvalue(L, 3); /* get environment for default files */
lua_setfenv(L, -2); /* set it as environment for file */
lua_setfield(L, 2, fname); /* add file to module */
}
static void newfenv (lua_State *L, lua_CFunction cls) {
/*
** pushes a new table with {__close = cls}
*/
static void newenv (lua_State *L, lua_CFunction cls) {
lua_createtable(L, 0, 1);
lua_pushcfunction(L, cls);
lua_setfield(L, -2, "__close");
@ -600,21 +611,21 @@ static void newfenv (lua_State *L, lua_CFunction cls) {
LUAMOD_API int luaopen_io (lua_State *L) {
lua_settop(L, 0);
createmeta(L);
/* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */
newfenv(L, io_fclose);
lua_replace(L, LUA_ENVIRONINDEX);
/* open library */
luaL_register(L, LUA_IOLIBNAME, iolib);
newenv(L, io_fclose); /* upvalue for all io functions at index 1 */
lua_pushvalue(L, -1); /* copy to be consumed by 'openlib' */
luaL_openlib(L, LUA_IOLIBNAME, iolib, 1); /* new module at index 2 */
/* create (and set) default files */
newfenv(L, io_noclose); /* close function for default files */
newenv(L, io_noclose); /* environment for default files at index 3 */
createstdfile(L, stdin, IO_INPUT, "stdin");
createstdfile(L, stdout, IO_OUTPUT, "stdout");
createstdfile(L, stderr, 0, "stderr");
lua_pop(L, 1); /* pop environment for default files */
lua_getfield(L, -1, "popen");
newfenv(L, io_pclose); /* create environment for 'popen' */
lua_setfenv(L, -2); /* set fenv for 'popen' */
lua_getfield(L, 2, "popen");
newenv(L, io_pclose); /* create environment for 'popen' streams */
lua_setupvalue(L, -2, 1); /* set it as upvalue for 'popen' */
lua_pop(L, 1); /* pop 'popen' */
return 1;
}

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@ -1,5 +1,5 @@
/*
** $Id: loadlib.c,v 1.79 2010/01/13 16:09:05 roberto Exp roberto $
** $Id: loadlib.c,v 1.80 2010/01/13 16:30:27 roberto Exp roberto $
** Dynamic library loader for Lua
** See Copyright Notice in lua.h
**
@ -353,9 +353,7 @@ static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
lua_CFunction f = ll_sym(L, *reg, sym);
if (f == NULL)
return ERRFUNC; /* unable to find function */
lua_pushcfunction(L, f); /* else create new function... */
lua_pushglobaltable(L); /* ... and set the standard global table... */
lua_setfenv(L, -2); /* ... as its environment */
lua_pushcfunction(L, f); /* else create new function */
return 0; /* no errors */
}
}
@ -435,7 +433,7 @@ static int ll_searchpath (lua_State *L) {
static const char *findfile (lua_State *L, const char *name,
const char *pname) {
const char *path;
lua_getfield(L, LUA_ENVIRONINDEX, pname);
lua_getfield(L, lua_upvalueindex(1), pname);
path = lua_tostring(L, -1);
if (path == NULL)
luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
@ -509,7 +507,7 @@ static int loader_Croot (lua_State *L) {
static int loader_preload (lua_State *L) {
const char *name = luaL_checkstring(L, 1);
lua_getfield(L, LUA_ENVIRONINDEX, "preload");
lua_getfield(L, lua_upvalueindex(1), "preload");
if (!lua_istable(L, -1))
luaL_error(L, LUA_QL("package.preload") " must be a table");
lua_getfield(L, -1, name);
@ -535,7 +533,7 @@ static int ll_require (lua_State *L) {
return 1; /* package is already loaded */
}
/* else must load it; iterate over available loaders */
lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
lua_getfield(L, lua_upvalueindex(1), "loaders");
if (!lua_istable(L, -1))
luaL_error(L, LUA_QL("package.loaders") " must be a table");
lua_pushliteral(L, ""); /* error message accumulator */
@ -709,12 +707,12 @@ LUAMOD_API int luaopen_package (lua_State *L) {
lua_setfield(L, -2, "__gc");
/* create `package' table */
luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
lua_copy(L, -1, LUA_ENVIRONINDEX);
/* create `loaders' table */
lua_createtable(L, sizeof(loaders)/sizeof(loaders[0]) - 1, 0);
/* fill it with pre-defined loaders */
for (i=0; loaders[i] != NULL; i++) {
lua_pushcfunction(L, loaders[i]);
lua_pushvalue(L, -2); /* set 'package' as upvalue for all loaders */
lua_pushcclosure(L, loaders[i], 1);
lua_rawseti(L, -2, i+1);
}
lua_setfield(L, -2, "loaders"); /* put it in field `loaders' */
@ -731,8 +729,9 @@ LUAMOD_API int luaopen_package (lua_State *L) {
lua_newtable(L);
lua_setfield(L, -2, "preload");
lua_pushglobaltable(L);
luaL_register(L, NULL, ll_funcs); /* open lib into global table */
lua_pop(L, 1);
lua_pushvalue(L, -2); /* set 'package' as upvalue for next lib */
luaL_openlib(L, NULL, ll_funcs, 1); /* open lib into global table */
lua_pop(L, 1); /* pop global table */
return 1; /* return 'package' table */
}