Lua 5.1-alpha5.1-alpha

1 files changed, 254 insertions, 119 deletions

diff --git a/src/loadlib.c b/src/loadlib.c
index 1ae9ab57..767fdb8e 100644
--- a/src/loadlib.c
+++ b/src/loadlib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: loadlib.c,v 1.28 2005/05/17 19:49:15 roberto Exp $
+** $Id: loadlib.c,v 1.44 2005/09/06 17:20:25 roberto Exp $
 ** Dynamic library loader for Lua
 ** See Copyright Notice in lua.h
 **
@@ -38,6 +38,13 @@
 #define LIB_FAIL	"open"
 
 
+/* error codes for ll_loadfunc */
+#define ERRLIB		1
+#define ERRFUNC		2
+
+#define setprogdir(L)		((void)0)
+
+
 static void ll_unloadlib (void *lib);
 static void *ll_load (lua_State *L, const char *path);
 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym);
@@ -88,6 +95,21 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 #include <windows.h>
 
 
+#undef setprogdir
+
+void setprogdir (lua_State *L) {
+  char buff[MAX_PATH + 1];
+  char *lb;
+  DWORD nsize = sizeof(buff)/sizeof(char);
+  DWORD n = GetModuleFileName(NULL, buff, nsize);
+  if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
+    luaL_error(L, "unable to get ModuleFileName");
+  *lb = '\0';
+  luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff);
+  lua_remove(L, -2);  /* remove original string */
+}
+
+
 static void pusherror (lua_State *L) {
   int error = GetLastError();
   char buffer[128];
@@ -267,96 +289,148 @@ static void **ll_register (lua_State *L, const char *path) {
 */
 static int gctm (lua_State *L) {
   void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB");
-  if (lib) {
-    if (*lib) ll_unloadlib(*lib);
-    *lib = NULL;  /* mark library as closed */
-  }
+  if (*lib) ll_unloadlib(*lib);
+  *lib = NULL;  /* mark library as closed */
   return 0;
 }
 
 
 static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
-  const char *reason;
   void **reg = ll_register(L, path);
   if (*reg == NULL) *reg = ll_load(L, path);
   if (*reg == NULL)
-    reason = LIB_FAIL;
+    return ERRLIB;  /* unable to load library */
   else {
     lua_CFunction f = ll_sym(L, *reg, sym);
-    if (f) {
-      lua_pushcfunction(L, f);
-      return 1;  /* return function */
-    }
-    reason = "init";
+    if (f == NULL)
+      return ERRFUNC;  /* unable to find function */
+    lua_pushcfunction(L, f);
+    return 0;  /* return function */
   }
-  lua_pushnil(L);
-  lua_insert(L, -2);
-  lua_pushstring(L, reason);
-  return 3;  /* return nil, ll_error, reason */
 }
 
 
 static int ll_loadlib (lua_State *L) {
   const char *path = luaL_checkstring(L, 1);
   const char *init = luaL_checkstring(L, 2);
-  return ll_loadfunc(L, path, init);
+  int stat = ll_loadfunc(L, path, init);
+  if (stat == 0)  /* no errors? */
+    return 1;  /* return the loaded function */
+  else {  /* error; error message is on stack top */
+    lua_pushnil(L);
+    lua_insert(L, -2);
+    lua_pushstring(L, (stat == ERRLIB) ?  LIB_FAIL : "init");
+    return 3;  /* return nil, error message, and where */
+  }
 }
 
 
 
 /*
 ** {======================================================
-** `require' and `module' functions
+** 'require' function
 ** =======================================================
 */
 
 
-static int loader_Lua (lua_State *L) {
-  const char *name = luaL_checkstring(L, 1);
-  const char *fname = luaL_gsub(L, name, ".", LUA_DIRSEP);
-  const char *path = NULL;
-#if LUA_COMPAT_PATH
-  /* try first `LUA_PATH' for compatibility */
-  lua_pushstring(L, "LUA_PATH");
-  lua_rawget(L, LUA_GLOBALSINDEX);
+static int readable (const char *filename) {
+  FILE *f = fopen(filename, "r");  /* try to open file */
+  if (f == NULL) return 0;  /* open failed */
+  fclose(f);
+  return 1;
+}
+
+
+static const char *pushnexttemplate (lua_State *L, const char *path) {
+  const char *l;
+  while (*path == *LUA_PATHSEP) path++;  /* skip separators */
+  if (*path == '\0') return NULL;  /* no more templates */
+  l = strchr(path, *LUA_PATHSEP);  /* find next separator */
+  if (l == NULL) l = path + strlen(path);
+  lua_pushlstring(L, path, l - path);  /* template */
+  return l;
+}
+
+
+static const char *findfile (lua_State *L, const char *name,
+                                           const char *pname) {
+  const char *path;
+  name = luaL_gsub(L, name, ".", LUA_DIRSEP);
+  lua_getfield(L, LUA_ENVIRONINDEX, pname);
   path = lua_tostring(L, -1);
-#endif
-  if (!path) {
-    lua_pop(L, 1);
-    lua_getfield(L, LUA_ENVIRONINDEX, "path");
-    path = lua_tostring(L, -1);
-  }
   if (path == NULL)
-    luaL_error(L, LUA_QL("package.path") " must be a string");
-  fname = luaL_searchpath(L, fname, path);
-  if (fname == NULL) return 0;  /* library not found in this path */
-  if (luaL_loadfile(L, fname) != 0)
-    luaL_error(L, "error loading package " LUA_QS " (%s)",
-                  name, lua_tostring(L, -1));
+    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
+  while ((path = pushnexttemplate(L, path)) != NULL) {
+    const char *filename;
+    filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
+    if (readable(filename))  /* does file exist and is readable? */
+      return filename;  /* return that file name */
+    lua_pop(L, 2);  /* remove path template and file name */ 
+  }
+  return NULL;  /* not found */
+}
+
+
+static void loaderror (lua_State *L) {
+  luaL_error(L, "error loading module " LUA_QS " (%s)",
+                lua_tostring(L, 1), lua_tostring(L, -1));
+}
+
+
+static int loader_Lua (lua_State *L) {
+  const char *filename;
+  const char *name = luaL_checkstring(L, 1);
+  filename = findfile(L, name, "path");
+  if (filename == NULL) return 0;  /* library not found in this path */
+  if (luaL_loadfile(L, filename) != 0)
+    loaderror(L);
   return 1;  /* library loaded successfully */
 }
 
 
+static const char *mkfuncname (lua_State *L, const char *modname) {
+  const char *funcname;
+  const char *mark = strchr(modname, *LUA_IGMARK);
+  if (mark) modname = mark + 1;
+  funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);
+  funcname = lua_pushfstring(L, POF"%s", funcname);
+  lua_remove(L, -2);  /* remove 'gsub' result */
+  return funcname;
+}
+
+
 static int loader_C (lua_State *L) {
-  const char *name = luaL_checkstring(L, 1);
-  const char *fname = luaL_gsub(L, name, ".", LUA_DIRSEP);
-  const char *path;
   const char *funcname;
-  lua_getfield(L, LUA_ENVIRONINDEX, "cpath");
-  path = lua_tostring(L, -1);
-  if (path == NULL)
-    luaL_error(L, LUA_QL("package.cpath") " must be a string");
-  fname = luaL_searchpath(L, fname, path);
-  if (fname == NULL) return 0;  /* library not found in this path */
-  funcname = luaL_gsub(L, name, ".", LUA_OFSEP);
-  funcname = lua_pushfstring(L, "%s%s", POF, funcname);
-  if (ll_loadfunc(L, fname, funcname) != 1)
-    luaL_error(L, "error loading package " LUA_QS " (%s)",
-                  name, lua_tostring(L, -2));
+  const char *name = luaL_checkstring(L, 1);
+  const char *filename = findfile(L, name, "cpath");
+  if (filename == NULL) return 0;  /* library not found in this path */
+  funcname = mkfuncname(L, name);
+  if (ll_loadfunc(L, filename, funcname) != 0)
+    loaderror(L);
   return 1;  /* library loaded successfully */
 }
 
 
+static int loader_Croot (lua_State *L) {
+  const char *funcname;
+  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");
+  if (filename == NULL) return 0;  /* root not found */
+  funcname = mkfuncname(L, name);
+  if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {
+    if (stat == ERRFUNC) return 0;  /* function not found */
+    else
+      loaderror(L);  /* real error */
+  }
+  return 1;
+}
+
+
 static int loader_preload (lua_State *L) {
   lua_getfield(L, LUA_ENVIRONINDEX, "preload");
   if (!lua_istable(L, -1))
@@ -366,38 +440,58 @@ static int loader_preload (lua_State *L) {
 }
 
 
+static const int sentinel = 0;
+
+
 static int ll_require (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
   int i;
-  lua_settop(L, 1);
+  lua_settop(L, 1);  /* _LOADED table will be at index 2 */
   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
   lua_getfield(L, 2, name);
-  if (lua_toboolean(L, -1))  /* is it there? */
-    return 1;  /* package is already loaded; return its result */
-  /* else must load it; first mark it as loaded */
-  lua_pushboolean(L, 1);
-  lua_setfield(L, 2, name);  /* _LOADED[name] = true */
-  /* iterate over available loaders */
+  if (lua_toboolean(L, -1)) {  /* is it there? */
+    if (lua_touserdata(L, -1) == &sentinel)  /* check loops */
+      luaL_error(L, "loop or previous error loading module " LUA_QS, name);
+    return 1;  /* package is already loaded */
+  }
+  /* else must load it; iterate over available loaders */
   lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
   if (!lua_istable(L, -1))
     luaL_error(L, LUA_QL("package.loaders") " must be a table");
-  for (i=1;; i++) {
+  for (i=1; ; i++) {
     lua_rawgeti(L, -1, i);  /* get a loader */
     if (lua_isnil(L, -1))
-      return luaL_error(L, "package " LUA_QS " not found", name);
+      luaL_error(L, "module " LUA_QS " not found", name);
     lua_pushstring(L, name);
     lua_call(L, 1, 1);  /* call it */
-    if (lua_isnil(L, -1)) lua_pop(L, 1);
+    if (lua_isnil(L, -1)) lua_pop(L, 1);  /* did not found module */
     else break;  /* module loaded successfully */
   }
-  lua_pushvalue(L, 1);  /* pass name as argument to module */
+  lua_pushlightuserdata(L, (void *)&sentinel);
+  lua_setfield(L, 2, name);  /* _LOADED[name] = sentinel */
+  lua_pushstring(L, name);  /* pass name as argument to module */
   lua_call(L, 1, 1);  /* run loaded module */
   if (!lua_isnil(L, -1))  /* non-nil return? */
-    lua_setfield(L, 2, name);  /* update _LOADED[name] with returned value */
-  lua_getfield(L, 2, name);  /* return _LOADED[name] */
+    lua_setfield(L, 2, name);  /* _LOADED[name] = returned value */
+  lua_getfield(L, 2, name);
+  if (lua_touserdata(L, -1) == &sentinel) {   /* module did not set a 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
+** =======================================================
+*/
+  
 
 static void setfenv (lua_State *L) {
   lua_Debug ar;
@@ -405,49 +499,72 @@ static void setfenv (lua_State *L) {
   lua_getinfo(L, "f", &ar);
   lua_pushvalue(L, -2);
   lua_setfenv(L, -2);
+  lua_pop(L, 1);
+}
+
+
+static void dooptions (lua_State *L, int n) {
+  int i;
+  for (i = 2; i <= n; i++) {
+    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);
-  const char *dot;
-  lua_settop(L, 1);
+  int loaded = lua_gettop(L) + 1;  /* index of _LOADED table */
   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
-  /* try to find given table */
-  luaL_getfield(L, LUA_GLOBALSINDEX, modname);
-  if (lua_isnil(L, -1)) {  /* not found? */
+  lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */
+  if (!lua_istable(L, -1)) {  /* not found? */
     lua_pop(L, 1);  /* remove previous result */
-    lua_newtable(L);  /* create it */
-    /* register it with given name */
+    /* try global variable (and create one if it does not exist) */
+    if (luaL_findtable(L, LUA_GLOBALSINDEX, modname) != NULL)
+      return luaL_error(L, "name conflict for module " LUA_QS, modname);
     lua_pushvalue(L, -1);
-    luaL_setfield(L, LUA_GLOBALSINDEX, modname);
+    lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new table */
   }
-  else if (!lua_istable(L, -1))
-    return luaL_error(L, "name conflict for module " LUA_QS, modname);
   /* check whether table already has a _NAME field */
   lua_getfield(L, -1, "_NAME");
   if (!lua_isnil(L, -1))  /* is table an initialized module? */
     lua_pop(L, 1);
   else {  /* no; initialize it */
     lua_pop(L, 1);
-    lua_newtable(L);  /* create new metatable */
-    lua_pushvalue(L, LUA_GLOBALSINDEX);
-    lua_setfield(L, -2, "__index");  /* mt.__index = _G */
-    lua_setmetatable(L, -2);
-    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");
+    modinit(L, modname);
   }
   lua_pushvalue(L, -1);
-  lua_setfield(L, 2, modname);  /* _LOADED[modname] = new table */
   setfenv(L);
+  dooptions(L, loaded - 1);
+  return 0;
+}
+
+
+static int ll_seeall (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  if (!lua_getmetatable(L, 1)) {
+    lua_newtable(L); /* create new metatable */
+    lua_pushvalue(L, -1);
+    lua_setmetatable(L, 1);
+  }
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  lua_setfield(L, -2, "__index");  /* mt.__index = _G */
   return 0;
 }
 
@@ -455,28 +572,57 @@ static int ll_module (lua_State *L) {
 /* }====================================================== */
 
 
-static const luaL_reg ll_funcs[] = {
-  {"require", ll_require},
+
+/* auxiliary mark (for internal use) */
+#define AUXMARK		"\1"
+
+static void setpath (lua_State *L, const char *fieldname, const char *envname,
+                                   const char *def) {
+  const char *path = getenv(envname);
+  if (path == NULL)  /* no environment variable? */
+    lua_pushstring(L, def);  /* use default */
+  else {
+    /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
+    path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
+                              LUA_PATHSEP AUXMARK LUA_PATHSEP);
+    luaL_gsub(L, path, AUXMARK, def);
+    lua_remove(L, -2);
+  }
+  setprogdir(L);
+  lua_setfield(L, -2, fieldname);
+}
+
+
+static const luaL_Reg pk_funcs[] = {
+  {"loadlib", ll_loadlib},
+  {"seeall", ll_seeall},
+  {NULL, NULL}
+};
+
+
+static const luaL_Reg ll_funcs[] = {
   {"module", ll_module},
+  {"require", ll_require},
   {NULL, NULL}
 };
 
 
 static const lua_CFunction loaders[] =
-  {loader_preload, loader_C, loader_Lua, NULL};
+  {loader_preload, loader_Lua, loader_C, loader_Croot, NULL};
 
 
-LUALIB_API int luaopen_loadlib (lua_State *L) {
-  const char *path;
+LUALIB_API int luaopen_package (lua_State *L) {
   int i;
   /* create new type _LOADLIB */
   luaL_newmetatable(L, "_LOADLIB");
   lua_pushcfunction(L, gctm);
   lua_setfield(L, -2, "__gc");
   /* create `package' table */
-  lua_newtable(L);
-  lua_pushvalue(L, -1);
-  lua_setglobal(L, LUA_LOADLIBNAME);
+  luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
+#if defined(LUA_COMPAT_LOADLIB) 
+  lua_getfield(L, -1, "loadlib");
+  lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
+#endif
   lua_pushvalue(L, -1);
   lua_setfield(L, LUA_REGISTRYINDEX, "_PACKAGE");
   lua_pushvalue(L, -1);
@@ -488,33 +634,22 @@ LUALIB_API int luaopen_loadlib (lua_State *L) {
     lua_pushcfunction(L, loaders[i]);
     lua_rawseti(L, -2, i+1);
   }
-  /* put it in field `loaders' */
-  lua_setfield(L, -2, "loaders");
-  /* set field `path' */
-  path = getenv(LUA_PATH);
-  if (path == NULL) path = LUA_PATH_DEFAULT;
-  lua_pushstring(L, path);
-  lua_setfield(L, -2, "path");
-  /* set field `cpath' */
-  path = getenv(LUA_CPATH);
-  if (path == NULL) path = LUA_CPATH_DEFAULT;
-  lua_pushstring(L, path);
-  lua_setfield(L, -2, "cpath");
+  lua_setfield(L, -2, "loaders");  /* put it in field `loaders' */
+  setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);  /* set field `path' */
+  setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */
+  /* store config information */
+  lua_pushstring(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
+                    LUA_EXECDIR "\n" LUA_IGMARK);
+  lua_setfield(L, -2, "config");
   /* set field `loaded' */
   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
   lua_setfield(L, -2, "loaded");
   /* set field `preload' */
   lua_newtable(L);
   lua_setfield(L, -2, "preload");
-  /* create `loadlib' function */
-  lua_pushcfunction(L, ll_loadlib);
-#if LUA_COMPAT_LOADLIB
-  lua_pushvalue(L, -1);
-  lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
-#endif
-  lua_setfield(L, -2, "loadlib");
   lua_pushvalue(L, LUA_GLOBALSINDEX);
-  luaL_openlib(L, NULL, ll_funcs, 0);  /* open lib into global table */
-  return 1;
+  luaL_register(L, NULL, ll_funcs);  /* open lib into global table */
+  lua_pop(L, 1);
+  return 1;  /* return 'package' table */
 }