commit 391c5459cbfb2a01a66b318f42cf780d952704b7
parent 62dd4cbe91617741a9f8e594201ad510d073b12d
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 15 Apr 2002 17:54:19 -0300
new implementation for `require' (with templates)
Diffstat:
| M | lbaselib.c | | | 175 | ++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------------- |
1 file changed, 119 insertions(+), 56 deletions(-)
diff --git a/lbaselib.c b/lbaselib.c
@@ -1,5 +1,5 @@
/*
-** $Id: lbaselib.c,v 1.66 2002/04/09 20:19:06 roberto Exp roberto $
+** $Id: lbaselib.c,v 1.67 2002/04/12 19:57:29 roberto Exp roberto $
** Basic library
** See Copyright Notice in lua.h
*/
@@ -200,6 +200,23 @@ static int luaB_next (lua_State *L) {
}
+static int luaB_nexti (lua_State *L) {
+ lua_Number i = lua_tonumber(L, 2);
+ luaL_check_type(L, 1, LUA_TTABLE);
+ if (i == 0) { /* `for' start? */
+ lua_getglobal(L, "nexti"); /* return generator, */
+ lua_pushvalue(L, 1); /* state, */
+ lua_pushnumber(L, 1); /* and initial value */
+ return 3;
+ }
+ else { /* `for' step */
+ lua_pushnumber(L, i+1); /* next value */
+ lua_rawgeti(L, 1, i);
+ return (lua_isnil(L, -1)) ? 0 : 2;
+ }
+}
+
+
static int passresults (lua_State *L, int status, int oldtop) {
if (status == 0) {
int nresults = lua_gettop(L) - oldtop;
@@ -259,58 +276,6 @@ static int luaB_assert (lua_State *L) {
}
-#define LUA_PATH "LUA_PATH"
-
-#define LUA_PATH_SEP ";"
-
-#ifndef LUA_PATH_DEFAULT
-#define LUA_PATH_DEFAULT "./"
-#endif
-
-static int luaB_require (lua_State *L) {
- const char *path;
- luaL_check_string(L, 1);
- lua_settop(L, 1);
- lua_getglobal(L, LUA_PATH); /* get path */
- if (lua_isstring(L, 2)) /* is LUA_PATH defined? */
- path = lua_tostring(L, 2);
- else { /* LUA_PATH not defined */
- lua_pop(L, 1); /* pop old global value */
- path = getenv(LUA_PATH); /* try environment variable */
- if (path == NULL) path = LUA_PATH_DEFAULT; /* else use default */
- lua_pushstring(L, path);
- lua_pushvalue(L, -1); /* duplicate to leave a copy on stack */
- lua_setglobal(L, LUA_PATH);
- }
- lua_pushvalue(L, 1); /* check package's name in book-keeping table */
- lua_gettable(L, lua_upvalueindex(1));
- if (!lua_isnil(L, -1)) /* is it there? */
- return 0; /* package is already loaded */
- else { /* must load it */
- for (;;) { /* traverse path */
- int res;
- int l = strcspn(path, LUA_PATH_SEP); /* find separator */
- lua_pushlstring(L, path, l); /* directory name */
- lua_pushvalue(L, 1); /* package name */
- lua_concat(L, 2); /* concat directory with package name */
- res = lua_dofile(L, lua_tostring(L, -1)); /* try to load it */
- lua_settop(L, 2); /* pop string and eventual results from dofile */
- if (res == 0) break; /* ok; file done */
- else if (res != LUA_ERRFILE)
- lua_error(L, NULL); /* error running package; propagate it */
- if (*(path+l) == '\0') /* no more directories? */
- luaL_verror(L, "could not load package `%.20s' from path `%.200s'",
- lua_tostring(L, 1), lua_tostring(L, 2));
- path += l+1; /* try next directory */
- }
- }
- lua_pushvalue(L, 1);
- lua_pushnumber(L, 1);
- lua_settable(L, lua_upvalueindex(1)); /* mark it as loaded */
- return 0;
-}
-
-
static int aux_unpack (lua_State *L, int arg) {
int n, i;
luaL_check_type(L, arg, LUA_TTABLE);
@@ -395,6 +360,104 @@ static int luaB_tostring (lua_State *L) {
}
+
+/*
+** {======================================================
+** `require' function
+** =======================================================
+*/
+
+
+/* name of global that holds table with loaded packages */
+#define REQTAB "_LOADED"
+
+/* name of global that holds the search path for packages */
+#define LUA_PATH "LUA_PATH"
+
+#ifndef LUA_PATH_SEP
+#define LUA_PATH_SEP ';'
+#endif
+
+#ifndef LUA_PATH_DEFAULT
+#define LUA_PATH_DEFAULT "?.lua"
+#endif
+
+
+static const char *getpath (lua_State *L) {
+ const char *path;
+ lua_getglobal(L, LUA_PATH); /* try global variable */
+ path = lua_tostring(L, -1);
+ if (path) return path;
+ path = getenv(LUA_PATH); /* else try environment variable */
+ if (path) return path;
+ return LUA_PATH_DEFAULT; /* else use default */
+}
+
+
+static const char *nextpath (lua_State *L, const char *path) {
+ const char *l;
+ if (*path == '\0') return NULL; /* no more pathes */
+ if (*path == LUA_PATH_SEP) path++; /* skip separator */
+ l = strchr(path, LUA_PATH_SEP); /* find next separator */
+ if (l == NULL) l = path+strlen(path);
+ lua_pushlstring(L, path, l - path); /* directory name */
+ return l;
+}
+
+
+static void composename (lua_State *L) {
+ const char *path = lua_tostring(L, -1);
+ const char *wild = strchr(path, '?');
+ if (wild == NULL) return; /* no wild char; path is the file name */
+ lua_pushlstring(L, path, wild - path);
+ lua_pushvalue(L, 1); /* package name */
+ lua_pushstring(L, wild + 1);
+ lua_concat(L, 3);
+}
+
+
+static int luaB_require (lua_State *L) {
+ const char *path;
+ int status = LUA_ERRFILE; /* not found (yet) */
+ luaL_check_string(L, 1);
+ lua_settop(L, 1);
+ lua_pushvalue(L, 1);
+ lua_setglobal(L, "_REQUIREDNAME");
+ lua_getglobal(L, REQTAB);
+ if (!lua_istable(L, 2)) lua_error(L, REQTAB " is not a table");
+ path = getpath(L);
+ lua_pushvalue(L, 1); /* check package's name in book-keeping table */
+ lua_gettable(L, 2);
+ if (!lua_isnil(L, -1)) /* is it there? */
+ return 0; /* package is already loaded */
+ else { /* must load it */
+ while (status == LUA_ERRFILE && (path = nextpath(L, path)) != NULL) {
+ composename(L);
+ status = lua_dofile(L, lua_tostring(L, -1)); /* try to load it */
+ lua_settop(L, 3); /* pop string and eventual results from dofile */
+ }
+ }
+ switch (status) {
+ case 0: {
+ lua_pushvalue(L, 1);
+ lua_pushboolean(L, 1);
+ lua_settable(L, 2); /* mark it as loaded */
+ return 0;
+ }
+ case LUA_ERRFILE: { /* file not found */
+ luaL_verror(L, "could not load package `%.20s' from path `%.200s'",
+ lua_tostring(L, 1), lua_tostring(L, 3));
+ }
+ default: { /* error loading package */
+ lua_error(L, NULL);
+ return 0; /* to avoid warnings */
+ }
+ }
+}
+
+/* }====================================================== */
+
+
static const luaL_reg base_funcs[] = {
{LUA_ALERT, luaB__ALERT},
{LUA_ERRORMESSAGE, luaB__ERRORMESSAGE},
@@ -402,6 +465,7 @@ static const luaL_reg base_funcs[] = {
{"metatable", luaB_metatable},
{"globals", luaB_globals},
{"next", luaB_next},
+ {"nexti", luaB_nexti},
{"print", luaB_print},
{"tonumber", luaB_tonumber},
{"tostring", luaB_tostring},
@@ -417,6 +481,7 @@ static const luaL_reg base_funcs[] = {
{"loadstring", luaB_loadstring},
{"dofile", luaB_dofile},
{"dostring", luaB_dostring},
+ {"require", luaB_require},
{NULL, NULL}
};
@@ -511,10 +576,8 @@ static void base_open (lua_State *L) {
LUALIB_API int lua_baselibopen (lua_State *L) {
base_open(L);
co_open(L);
- /* `require' needs an empty table as upvalue */
lua_newtable(L);
- lua_pushcclosure(L, luaB_require, 1);
- lua_setglobal(L, "require");
+ lua_setglobal(L, REQTAB);
return 0;
}
