789 lines
23 KiB
C++
789 lines
23 KiB
C++
/*
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** $Id: loadlib.c,v 1.130 2017/01/12 17:14:26 roberto Exp $
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** Dynamic library loader for Lua
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** See Copyright Notice in lua.h
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**
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** This module contains an implementation of loadlib for Unix systems
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** that have dlfcn, an implementation for Windows, and a stub for other
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** systems.
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*/
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#define loadlib_c
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#define LUA_LIB
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#include "lprefix.h"
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "lua.h"
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#include "lauxlib.h"
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#include "lualib.h"
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#if defined(LUA_USE_DLOPEN)
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#include <dlfcn.h>
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#elif defined(LUA_DL_DLL)
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#include <windows.h>
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#endif
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namespace NS_SLUA {
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/*
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** LUA_IGMARK is a mark to ignore all before it when building the
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** luaopen_ function name.
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*/
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#if !defined (LUA_IGMARK)
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#define LUA_IGMARK "-"
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#endif
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/*
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** LUA_CSUBSEP is the character that replaces dots in submodule names
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** when searching for a C loader.
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** LUA_LSUBSEP is the character that replaces dots in submodule names
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** when searching for a Lua loader.
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*/
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#if !defined(LUA_CSUBSEP)
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#define LUA_CSUBSEP LUA_DIRSEP
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#endif
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#if !defined(LUA_LSUBSEP)
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#define LUA_LSUBSEP LUA_DIRSEP
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#endif
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/* prefix for open functions in C libraries */
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#define LUA_POF "luaopen_"
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/* separator for open functions in C libraries */
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#define LUA_OFSEP "_"
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/*
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** unique key for table in the registry that keeps handles
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** for all loaded C libraries
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*/
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static const int CLIBS = 0;
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#define LIB_FAIL "open"
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#define setprogdir(L) ((void)0)
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/*
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** system-dependent functions
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*/
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/*
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** unload library 'lib'
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*/
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static void lsys_unloadlib (void *lib);
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/*
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** load C library in file 'path'. If 'seeglb', load with all names in
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** the library global.
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** Returns the library; in case of error, returns NULL plus an
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** error string in the stack.
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*/
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static void *lsys_load (lua_State *L, const char *path, int seeglb);
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/*
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** Try to find a function named 'sym' in library 'lib'.
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** Returns the function; in case of error, returns NULL plus an
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** error string in the stack.
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*/
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static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym);
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#if defined(LUA_USE_DLOPEN) /* { */
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/*
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** {========================================================================
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** This is an implementation of loadlib based on the dlfcn interface.
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** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
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** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least
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** as an emulation layer on top of native functions.
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** =========================================================================
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*/
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/*
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** Macro to convert pointer-to-void* to pointer-to-function. This cast
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** is undefined according to ISO C, but POSIX assumes that it works.
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** (The '__extension__' in gnu compilers is only to avoid warnings.)
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*/
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#if defined(__GNUC__)
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#define cast_func(p) (__extension__ (lua_CFunction)(p))
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#else
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#define cast_func(p) ((lua_CFunction)(p))
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#endif
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static void lsys_unloadlib (void *lib) {
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dlclose(lib);
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}
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static void *lsys_load (lua_State *L, const char *path, int seeglb) {
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void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL));
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if (lib == NULL) lua_pushstring(L, dlerror());
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return lib;
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}
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static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
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lua_CFunction f = cast_func(dlsym(lib, sym));
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if (f == NULL) lua_pushstring(L, dlerror());
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return f;
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}
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/* }====================================================== */
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#elif defined(LUA_DL_DLL) /* }{ */
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/*
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** {======================================================================
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** This is an implementation of loadlib for Windows using native functions.
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** =======================================================================
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*/
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/*
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** optional flags for LoadLibraryEx
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*/
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#if !defined(LUA_LLE_FLAGS)
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#define LUA_LLE_FLAGS 0
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#endif
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#undef setprogdir
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/*
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** Replace in the path (on the top of the stack) any occurrence
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** of LUA_EXEC_DIR with the executable's path.
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*/
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static void setprogdir (lua_State *L) {
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char buff[MAX_PATH + 1];
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char *lb;
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DWORD nsize = sizeof(buff)/sizeof(char);
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DWORD n = GetModuleFileNameA(NULL, buff, nsize); /* get exec. name */
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if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
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luaL_error(L, "unable to get ModuleFileName");
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else {
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*lb = '\0'; /* cut name on the last '\\' to get the path */
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luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, buff);
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lua_remove(L, -2); /* remove original string */
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}
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}
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static void pusherror (lua_State *L) {
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int error = GetLastError();
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char buffer[128];
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if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
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NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL))
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lua_pushstring(L, buffer);
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else
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lua_pushfstring(L, "system error %d\n", error);
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}
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static void lsys_unloadlib (void *lib) {
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FreeLibrary((HMODULE)lib);
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}
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static void *lsys_load (lua_State *L, const char *path, int seeglb) {
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HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS);
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(void)(seeglb); /* not used: symbols are 'global' by default */
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if (lib == NULL) pusherror(L);
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return lib;
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}
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static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
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lua_CFunction f = (lua_CFunction)GetProcAddress((HMODULE)lib, sym);
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if (f == NULL) pusherror(L);
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return f;
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}
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/* }====================================================== */
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#else /* }{ */
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/*
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** {======================================================
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** Fallback for other systems
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** =======================================================
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*/
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#undef LIB_FAIL
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#define LIB_FAIL "absent"
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#define DLMSG "dynamic libraries not enabled; check your Lua installation"
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static void lsys_unloadlib (void *lib) {
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(void)(lib); /* not used */
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}
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static void *lsys_load (lua_State *L, const char *path, int seeglb) {
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(void)(path); (void)(seeglb); /* not used */
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lua_pushliteral(L, DLMSG);
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return NULL;
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}
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static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
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(void)(lib); (void)(sym); /* not used */
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lua_pushliteral(L, DLMSG);
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return NULL;
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}
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/* }====================================================== */
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#endif /* } */
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/*
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** {==================================================================
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** Set Paths
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** ===================================================================
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*/
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/*
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** LUA_PATH_VAR and LUA_CPATH_VAR are the names of the environment
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** variables that Lua check to set its paths.
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*/
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#if !defined(LUA_PATH_VAR)
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#define LUA_PATH_VAR "LUA_PATH"
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#endif
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#if !defined(LUA_CPATH_VAR)
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#define LUA_CPATH_VAR "LUA_CPATH"
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#endif
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#define AUXMARK "\1" /* auxiliary mark */
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/*
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** return registry.LUA_NOENV as a boolean
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*/
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static int noenv (lua_State *L) {
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int b;
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lua_getfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
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b = lua_toboolean(L, -1);
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lua_pop(L, 1); /* remove value */
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return b;
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}
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/*
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** Set a path
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*/
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static void setpath (lua_State *L, const char *fieldname,
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const char *envname,
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const char *dft) {
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const char *nver = lua_pushfstring(L, "%s%s", envname, LUA_VERSUFFIX);
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const char *path = getenv(nver); /* use versioned name */
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if (path == NULL) /* no environment variable? */
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path = getenv(envname); /* try unversioned name */
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if (path == NULL || noenv(L)) /* no environment variable? */
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lua_pushstring(L, dft); /* use default */
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else {
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/* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
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path = luaL_gsub(L, path, LUA_PATH_SEP LUA_PATH_SEP,
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LUA_PATH_SEP AUXMARK LUA_PATH_SEP);
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luaL_gsub(L, path, AUXMARK, dft);
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lua_remove(L, -2); /* remove result from 1st 'gsub' */
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}
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setprogdir(L);
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lua_setfield(L, -3, fieldname); /* package[fieldname] = path value */
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lua_pop(L, 1); /* pop versioned variable name */
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}
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/* }================================================================== */
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/*
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** return registry.CLIBS[path]
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*/
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static void *checkclib (lua_State *L, const char *path) {
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void *plib;
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lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS);
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lua_getfield(L, -1, path);
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plib = lua_touserdata(L, -1); /* plib = CLIBS[path] */
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lua_pop(L, 2); /* pop CLIBS table and 'plib' */
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return plib;
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}
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/*
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** registry.CLIBS[path] = plib -- for queries
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** registry.CLIBS[#CLIBS + 1] = plib -- also keep a list of all libraries
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*/
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static void addtoclib (lua_State *L, const char *path, void *plib) {
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lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS);
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lua_pushlightuserdata(L, plib);
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lua_pushvalue(L, -1);
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lua_setfield(L, -3, path); /* CLIBS[path] = plib */
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lua_rawseti(L, -2, luaL_len(L, -2) + 1); /* CLIBS[#CLIBS + 1] = plib */
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lua_pop(L, 1); /* pop CLIBS table */
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}
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/*
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** __gc tag method for CLIBS table: calls 'lsys_unloadlib' for all lib
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** handles in list CLIBS
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*/
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static int gctm (lua_State *L) {
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lua_Integer n = luaL_len(L, 1);
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for (; n >= 1; n--) { /* for each handle, in reverse order */
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lua_rawgeti(L, 1, n); /* get handle CLIBS[n] */
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lsys_unloadlib(lua_touserdata(L, -1));
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lua_pop(L, 1); /* pop handle */
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}
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return 0;
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}
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/* error codes for 'lookforfunc' */
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#define ERRLIB 1
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#define ERRFUNC 2
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/*
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** Look for a C function named 'sym' in a dynamically loaded library
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** 'path'.
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** First, check whether the library is already loaded; if not, try
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** to load it.
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** Then, if 'sym' is '*', return true (as library has been loaded).
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** Otherwise, look for symbol 'sym' in the library and push a
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** C function with that symbol.
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** Return 0 and 'true' or a function in the stack; in case of
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** errors, return an error code and an error message in the stack.
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*/
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static int lookforfunc (lua_State *L, const char *path, const char *sym) {
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void *reg = checkclib(L, path); /* check loaded C libraries */
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if (reg == NULL) { /* must load library? */
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reg = lsys_load(L, path, *sym == '*'); /* global symbols if 'sym'=='*' */
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if (reg == NULL) return ERRLIB; /* unable to load library */
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addtoclib(L, path, reg);
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}
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if (*sym == '*') { /* loading only library (no function)? */
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lua_pushboolean(L, 1); /* return 'true' */
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return 0; /* no errors */
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}
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else {
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lua_CFunction f = lsys_sym(L, reg, sym);
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if (f == NULL)
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return ERRFUNC; /* unable to find function */
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lua_pushcfunction(L, f); /* else create new function */
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return 0; /* no errors */
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}
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}
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static int ll_loadlib (lua_State *L) {
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const char *path = luaL_checkstring(L, 1);
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const char *init = luaL_checkstring(L, 2);
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int stat = lookforfunc(L, path, init);
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if (stat == 0) /* no errors? */
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return 1; /* return the loaded function */
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else { /* error; error message is on stack top */
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lua_pushnil(L);
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lua_insert(L, -2);
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lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init");
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return 3; /* return nil, error message, and where */
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}
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}
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/*
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** {======================================================
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** 'require' function
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** =======================================================
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*/
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static int readable (const char *filename) {
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FILE *f = fopen(filename, "r"); /* try to open file */
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if (f == NULL) return 0; /* open failed */
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fclose(f);
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return 1;
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}
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static const char *pushnexttemplate (lua_State *L, const char *path) {
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const char *l;
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while (*path == *LUA_PATH_SEP) path++; /* skip separators */
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if (*path == '\0') return NULL; /* no more templates */
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l = strchr(path, *LUA_PATH_SEP); /* find next separator */
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if (l == NULL) l = path + strlen(path);
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lua_pushlstring(L, path, l - path); /* template */
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return l;
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}
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static const char *searchpath (lua_State *L, const char *name,
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const char *path,
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const char *sep,
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const char *dirsep) {
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luaL_Buffer msg; /* to build error message */
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luaL_buffinit(L, &msg);
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if (*sep != '\0') /* non-empty separator? */
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name = luaL_gsub(L, name, sep, dirsep); /* replace it by 'dirsep' */
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while ((path = pushnexttemplate(L, path)) != NULL) {
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const char *filename = luaL_gsub(L, lua_tostring(L, -1),
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LUA_PATH_MARK, name);
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lua_remove(L, -2); /* remove path template */
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if (readable(filename)) /* does file exist and is readable? */
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return filename; /* return that file name */
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lua_pushfstring(L, "\n\tno file '%s'", filename);
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lua_remove(L, -2); /* remove file name */
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luaL_addvalue(&msg); /* concatenate error msg. entry */
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}
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luaL_pushresult(&msg); /* create error message */
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return NULL; /* not found */
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}
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static int ll_searchpath (lua_State *L) {
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const char *f = searchpath(L, luaL_checkstring(L, 1),
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luaL_checkstring(L, 2),
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luaL_optstring(L, 3, "."),
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luaL_optstring(L, 4, LUA_DIRSEP));
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if (f != NULL) return 1;
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else { /* error message is on top of the stack */
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lua_pushnil(L);
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lua_insert(L, -2);
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return 2; /* return nil + error message */
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}
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}
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static const char *findfile (lua_State *L, const char *name,
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const char *pname,
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const char *dirsep) {
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const char *path;
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lua_getfield(L, lua_upvalueindex(1), pname);
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path = lua_tostring(L, -1);
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if (path == NULL)
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luaL_error(L, "'package.%s' must be a string", pname);
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return searchpath(L, name, path, ".", dirsep);
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}
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static int checkload (lua_State *L, int stat, const char *filename) {
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if (stat) { /* module loaded successfully? */
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lua_pushstring(L, filename); /* will be 2nd argument to module */
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return 2; /* return open function and file name */
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}
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else
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return luaL_error(L, "error loading module '%s' from file '%s':\n\t%s",
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lua_tostring(L, 1), filename, lua_tostring(L, -1));
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}
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static int searcher_Lua (lua_State *L) {
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const char *filename;
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const char *name = luaL_checkstring(L, 1);
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filename = findfile(L, name, "path", LUA_LSUBSEP);
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if (filename == NULL) return 1; /* module not found in this path */
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return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename);
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}
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/*
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** Try to find a load function for module 'modname' at file 'filename'.
|
|
** First, change '.' to '_' in 'modname'; then, if 'modname' has
|
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** the form X-Y (that is, it has an "ignore mark"), build a function
|
|
** name "luaopen_X" and look for it. (For compatibility, if that
|
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** fails, it also tries "luaopen_Y".) If there is no ignore mark,
|
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** look for a function named "luaopen_modname".
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*/
|
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static int loadfunc (lua_State *L, const char *filename, const char *modname) {
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const char *openfunc;
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const char *mark;
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modname = luaL_gsub(L, modname, ".", LUA_OFSEP);
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mark = strchr(modname, *LUA_IGMARK);
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if (mark) {
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int stat;
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openfunc = lua_pushlstring(L, modname, mark - modname);
|
|
openfunc = lua_pushfstring(L, LUA_POF"%s", openfunc);
|
|
stat = lookforfunc(L, filename, openfunc);
|
|
if (stat != ERRFUNC) return stat;
|
|
modname = mark + 1; /* else go ahead and try old-style name */
|
|
}
|
|
openfunc = lua_pushfstring(L, LUA_POF"%s", modname);
|
|
return lookforfunc(L, filename, openfunc);
|
|
}
|
|
|
|
|
|
static int searcher_C (lua_State *L) {
|
|
const char *name = luaL_checkstring(L, 1);
|
|
const char *filename = findfile(L, name, "cpath", LUA_CSUBSEP);
|
|
if (filename == NULL) return 1; /* module not found in this path */
|
|
return checkload(L, (loadfunc(L, filename, name) == 0), filename);
|
|
}
|
|
|
|
|
|
static int searcher_Croot (lua_State *L) {
|
|
const char *filename;
|
|
const char *name = luaL_checkstring(L, 1);
|
|
const char *p = strchr(name, '.');
|
|
int stat;
|
|
if (p == NULL) return 0; /* is root */
|
|
lua_pushlstring(L, name, p - name);
|
|
filename = findfile(L, lua_tostring(L, -1), "cpath", LUA_CSUBSEP);
|
|
if (filename == NULL) return 1; /* root not found */
|
|
if ((stat = loadfunc(L, filename, name)) != 0) {
|
|
if (stat != ERRFUNC)
|
|
return checkload(L, 0, filename); /* real error */
|
|
else { /* open function not found */
|
|
lua_pushfstring(L, "\n\tno module '%s' in file '%s'", name, filename);
|
|
return 1;
|
|
}
|
|
}
|
|
lua_pushstring(L, filename); /* will be 2nd argument to module */
|
|
return 2;
|
|
}
|
|
|
|
|
|
static int searcher_preload (lua_State *L) {
|
|
const char *name = luaL_checkstring(L, 1);
|
|
lua_getfield(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
|
|
if (lua_getfield(L, -1, name) == LUA_TNIL) /* not found? */
|
|
lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
|
|
return 1;
|
|
}
|
|
|
|
|
|
static void findloader (lua_State *L, const char *name) {
|
|
int i;
|
|
luaL_Buffer msg; /* to build error message */
|
|
luaL_buffinit(L, &msg);
|
|
/* push 'package.searchers' to index 3 in the stack */
|
|
if (lua_getfield(L, lua_upvalueindex(1), "searchers") != LUA_TTABLE)
|
|
luaL_error(L, "'package.searchers' must be a table");
|
|
/* iterate over available searchers to find a loader */
|
|
for (i = 1; ; i++) {
|
|
if (lua_rawgeti(L, 3, i) == LUA_TNIL) { /* no more searchers? */
|
|
lua_pop(L, 1); /* remove nil */
|
|
luaL_pushresult(&msg); /* create error message */
|
|
luaL_error(L, "module '%s' not found:%s", name, lua_tostring(L, -1));
|
|
}
|
|
lua_pushstring(L, name);
|
|
lua_call(L, 1, 2); /* call it */
|
|
if (lua_isfunction(L, -2)) /* did it find a loader? */
|
|
return; /* module loader found */
|
|
else if (lua_isstring(L, -2)) { /* searcher returned error message? */
|
|
lua_pop(L, 1); /* remove extra return */
|
|
luaL_addvalue(&msg); /* concatenate error message */
|
|
}
|
|
else
|
|
lua_pop(L, 2); /* remove both returns */
|
|
}
|
|
}
|
|
|
|
|
|
static int ll_require (lua_State *L) {
|
|
const char *name = luaL_checkstring(L, 1);
|
|
lua_settop(L, 1); /* LOADED table will be at index 2 */
|
|
lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
|
|
lua_getfield(L, 2, name); /* LOADED[name] */
|
|
if (lua_toboolean(L, -1)) /* is it there? */
|
|
return 1; /* package is already loaded */
|
|
/* else must load package */
|
|
lua_pop(L, 1); /* remove 'getfield' result */
|
|
findloader(L, name);
|
|
lua_pushstring(L, name); /* pass name as argument to module loader */
|
|
lua_insert(L, -2); /* name is 1st argument (before search data) */
|
|
lua_call(L, 2, 1); /* run loader to load module */
|
|
if (!lua_isnil(L, -1)) /* non-nil return? */
|
|
lua_setfield(L, 2, name); /* LOADED[name] = returned value */
|
|
if (lua_getfield(L, 2, name) == LUA_TNIL) { /* module set no value? */
|
|
lua_pushboolean(L, 1); /* use true as result */
|
|
lua_pushvalue(L, -1); /* extra copy to be returned */
|
|
lua_setfield(L, 2, name); /* LOADED[name] = true */
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/* }====================================================== */
|
|
|
|
|
|
|
|
/*
|
|
** {======================================================
|
|
** 'module' function
|
|
** =======================================================
|
|
*/
|
|
#if defined(LUA_COMPAT_MODULE)
|
|
|
|
/*
|
|
** changes the environment variable of calling function
|
|
*/
|
|
static void set_env (lua_State *L) {
|
|
lua_Debug ar;
|
|
if (lua_getstack(L, 1, &ar) == 0 ||
|
|
lua_getinfo(L, "f", &ar) == 0 || /* get calling function */
|
|
lua_iscfunction(L, -1))
|
|
luaL_error(L, "'module' not called from a Lua function");
|
|
lua_pushvalue(L, -2); /* copy new environment table to top */
|
|
lua_setupvalue(L, -2, 1);
|
|
lua_pop(L, 1); /* remove function */
|
|
}
|
|
|
|
|
|
static void dooptions (lua_State *L, int n) {
|
|
int i;
|
|
for (i = 2; i <= n; i++) {
|
|
if (lua_isfunction(L, i)) { /* avoid 'calling' extra info. */
|
|
lua_pushvalue(L, i); /* get option (a function) */
|
|
lua_pushvalue(L, -2); /* module */
|
|
lua_call(L, 1, 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
static void modinit (lua_State *L, const char *modname) {
|
|
const char *dot;
|
|
lua_pushvalue(L, -1);
|
|
lua_setfield(L, -2, "_M"); /* module._M = module */
|
|
lua_pushstring(L, modname);
|
|
lua_setfield(L, -2, "_NAME");
|
|
dot = strrchr(modname, '.'); /* look for last dot in module name */
|
|
if (dot == NULL) dot = modname;
|
|
else dot++;
|
|
/* set _PACKAGE as package name (full module name minus last part) */
|
|
lua_pushlstring(L, modname, dot - modname);
|
|
lua_setfield(L, -2, "_PACKAGE");
|
|
}
|
|
|
|
|
|
static int ll_module (lua_State *L) {
|
|
const char *modname = luaL_checkstring(L, 1);
|
|
int lastarg = lua_gettop(L); /* last parameter */
|
|
luaL_pushmodule(L, modname, 1); /* get/create module table */
|
|
/* check whether table already has a _NAME field */
|
|
if (lua_getfield(L, -1, "_NAME") != LUA_TNIL)
|
|
lua_pop(L, 1); /* table is an initialized module */
|
|
else { /* no; initialize it */
|
|
lua_pop(L, 1);
|
|
modinit(L, modname);
|
|
}
|
|
lua_pushvalue(L, -1);
|
|
set_env(L);
|
|
dooptions(L, lastarg);
|
|
return 1;
|
|
}
|
|
|
|
|
|
static int ll_seeall (lua_State *L) {
|
|
luaL_checktype(L, 1, LUA_TTABLE);
|
|
if (!lua_getmetatable(L, 1)) {
|
|
lua_createtable(L, 0, 1); /* create new metatable */
|
|
lua_pushvalue(L, -1);
|
|
lua_setmetatable(L, 1);
|
|
}
|
|
lua_pushglobaltable(L);
|
|
lua_setfield(L, -2, "__index"); /* mt.__index = _G */
|
|
return 0;
|
|
}
|
|
|
|
#endif
|
|
/* }====================================================== */
|
|
|
|
|
|
|
|
static const luaL_Reg pk_funcs[] = {
|
|
{"loadlib", ll_loadlib},
|
|
{"searchpath", ll_searchpath},
|
|
#if defined(LUA_COMPAT_MODULE)
|
|
{"seeall", ll_seeall},
|
|
#endif
|
|
/* placeholders */
|
|
{"preload", NULL},
|
|
{"cpath", NULL},
|
|
{"path", NULL},
|
|
{"searchers", NULL},
|
|
{"loaded", NULL},
|
|
{NULL, NULL}
|
|
};
|
|
|
|
|
|
static const luaL_Reg ll_funcs[] = {
|
|
#if defined(LUA_COMPAT_MODULE)
|
|
{"module", ll_module},
|
|
#endif
|
|
{"require", ll_require},
|
|
{NULL, NULL}
|
|
};
|
|
|
|
|
|
static void createsearcherstable (lua_State *L) {
|
|
static const lua_CFunction searchers[] =
|
|
{searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL};
|
|
int i;
|
|
/* create 'searchers' table */
|
|
lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0);
|
|
/* fill it with predefined searchers */
|
|
for (i=0; searchers[i] != NULL; i++) {
|
|
lua_pushvalue(L, -2); /* set 'package' as upvalue for all searchers */
|
|
lua_pushcclosure(L, searchers[i], 1);
|
|
lua_rawseti(L, -2, i+1);
|
|
}
|
|
#if defined(LUA_COMPAT_LOADERS)
|
|
lua_pushvalue(L, -1); /* make a copy of 'searchers' table */
|
|
lua_setfield(L, -3, "loaders"); /* put it in field 'loaders' */
|
|
#endif
|
|
lua_setfield(L, -2, "searchers"); /* put it in field 'searchers' */
|
|
}
|
|
|
|
|
|
/*
|
|
** create table CLIBS to keep track of loaded C libraries,
|
|
** setting a finalizer to close all libraries when closing state.
|
|
*/
|
|
static void createclibstable (lua_State *L) {
|
|
lua_newtable(L); /* create CLIBS table */
|
|
lua_createtable(L, 0, 1); /* create metatable for CLIBS */
|
|
lua_pushcfunction(L, gctm);
|
|
lua_setfield(L, -2, "__gc"); /* set finalizer for CLIBS table */
|
|
lua_setmetatable(L, -2);
|
|
lua_rawsetp(L, LUA_REGISTRYINDEX, &CLIBS); /* set CLIBS table in registry */
|
|
}
|
|
|
|
|
|
LUAMOD_API int luaopen_package (lua_State *L) {
|
|
createclibstable(L);
|
|
luaL_newlib(L, pk_funcs); /* create 'package' table */
|
|
createsearcherstable(L);
|
|
/* set paths */
|
|
setpath(L, "path", LUA_PATH_VAR, LUA_PATH_DEFAULT);
|
|
setpath(L, "cpath", LUA_CPATH_VAR, LUA_CPATH_DEFAULT);
|
|
/* store config information */
|
|
lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
|
|
LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
|
|
lua_setfield(L, -2, "config");
|
|
/* set field 'loaded' */
|
|
luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
|
|
lua_setfield(L, -2, "loaded");
|
|
/* set field 'preload' */
|
|
luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
|
|
lua_setfield(L, -2, "preload");
|
|
lua_pushglobaltable(L);
|
|
lua_pushvalue(L, -2); /* set 'package' as upvalue for next lib */
|
|
luaL_setfuncs(L, ll_funcs, 1); /* open lib into global table */
|
|
lua_pop(L, 1); /* pop global table */
|
|
return 1; /* return 'package' table */
|
|
}
|
|
|
|
} // end NS_SLUA
|