Lua: add the package library

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21506 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/helloworld.lua

@@ -21,7 +21,7 @@
 
 ]]--
 
-dofile("actions.lua") -- Contains rb.actions & rb.contexts
+require("actions") -- Contains rb.actions & rb.contexts
 
 -- Example function which splashes a message for x seconds
 function sayhello(seconds)

apps/plugins/lua/SOURCES

@@ -10,6 +10,7 @@ lfunc.c
 lgc.c
 llex.c
 lmem.c
+loadlib.c
 lobject.c
 lopcodes.c
 loslib.c

apps/plugins/lua/lauxlib.c

@@ -560,62 +560,14 @@ static int errfile (lua_State *L, const char *what, int fnameindex) {
   return LUA_ERRFILE;
 }
 
-bool get_cur_path(lua_State *L, char* dest, size_t dest_size)
-{
-    lua_Debug ar;
-    if(lua_getstack(L, 1, &ar))
-    {
-        /* Try determining the base path of the current Lua chunk
-            and write it to dest. */
-        lua_getinfo(L, "S", &ar);
-
-        char* curfile = (char*) &ar.source[1];
-        char* pos = rb->strrchr(curfile, '/');
-        if(pos != NULL)
-        {
-            unsigned int len = (unsigned int)(pos - curfile);
-            len = len + 1 > dest_size ? dest_size - 1 : len;
-
-            if(len > 0)
-                memcpy(dest, curfile, len);
-
-            dest[len] = '/';
-            dest[len+1] = '\0';
-
-            return true;
-        }
-        else
-            return false;
-    }
-    else
-        return false;
-}
-
 LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
   LoadF lf;
   int status;
-  char buffer[MAX_PATH];
   int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
   lf.extraline = 0;
   lf.f = rb->open(filename, O_RDONLY);
   lua_pushfstring(L, "@%s", filename);
-  if(lf.f < 0) {
-    /* Fallback */
-
-    if(get_cur_path(L, buffer, sizeof(buffer))) {
-      strncat(buffer, filename, sizeof(buffer) - strlen(buffer));
-      lf.f = rb->open(buffer, O_RDONLY);
-    }
-
-    if(lf.f < 0) {
-      snprintf(buffer, sizeof(buffer), "%s/%s", VIEWERS_DIR, filename);
-      lf.f = rb->open(buffer, O_RDONLY);
-
-      if(lf.f < 0)
-        return errfile(L, "open", fnameindex);
-    }
-  }
-
+  if (lf.f < 0) return errfile(L, "open", fnameindex);
   status = lua_load(L, getF, &lf, lua_tostring(L, -1));
   rb->close(lf.f);
   lua_remove(L, fnameindex);

apps/plugins/lua/loadlib.c

@@ -0,0 +1,313 @@
+/*
+** $Id: loadlib.c,v 1.52.1.3 2008/08/06 13:29:28 roberto Exp $
+** Dynamic library loader for Lua
+** See Copyright Notice in lua.h
+**
+** This module contains an implementation of loadlib for Unix systems
+** that have dlfcn, an implementation for Darwin (Mac OS X), an
+** implementation for Windows, and a stub for other systems.
+*/
+
+
+#include <stdlib.h>
+#include <string.h>
+
+
+#define loadlib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#define setprogdir(L)       ((void)0)
+
+
+/*
+** {======================================================
+** 'require' function
+** =======================================================
+*/
+
+
+static int readable (const char *filename) {
+  int f = rb->open(filename, O_RDONLY);  /* try to open file */
+  if (f < 0) return 0;  /* open failed */
+  rb->close(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);
+  if (path == NULL)
+    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
+  lua_pushliteral(L, "");  /* error accumulator */
+  while ((path = pushnexttemplate(L, path)) != NULL) {
+    const char *filename;
+    filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
+    lua_remove(L, -2);  /* remove path template */
+    if (readable(filename))  /* does file exist and is readable? */
+      return filename;  /* return that file name */
+    lua_pushfstring(L, "\n\tno file " LUA_QS, filename);
+    lua_remove(L, -2);  /* remove file name */
+    lua_concat(L, 2);  /* add entry to possible error message */
+  }
+  return NULL;  /* not found */
+}
+
+
+static void loaderror (lua_State *L, const char *filename) {
+  luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
+                lua_tostring(L, 1), filename, 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 1;  /* library not found in this path */
+  if (luaL_loadfile(L, filename) != 0)
+    loaderror(L, filename);
+  return 1;  /* library loaded successfully */
+}
+
+
+static int loader_preload (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  lua_getfield(L, LUA_ENVIRONINDEX, "preload");
+  if (!lua_istable(L, -1))
+    luaL_error(L, LUA_QL("package.preload") " must be a table");
+  lua_getfield(L, -1, name);
+  if (lua_isnil(L, -1))  /* not found? */
+    lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
+  return 1;
+}
+
+
+static const int sentinel_ = 0;
+#define sentinel    ((void *)&sentinel_)
+
+
+static int ll_require (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  int i;
+  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? */
+    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");
+  lua_pushliteral(L, "");  /* error message accumulator */
+  for (i=1; ; i++) {
+    lua_rawgeti(L, -2, i);  /* get a loader */
+    if (lua_isnil(L, -1))
+      luaL_error(L, "module " LUA_QS " not found:%s",
+                    name, lua_tostring(L, -2));
+    lua_pushstring(L, name);
+    lua_call(L, 1, 1);  /* call it */
+    if (lua_isfunction(L, -1))  /* did it find module? */
+      break;  /* module loaded successfully */
+    else if (lua_isstring(L, -1))  /* loader returned error message? */
+      lua_concat(L, 2);  /* accumulate it */
+    else
+      lua_pop(L, 1);
+  }
+  lua_pushlightuserdata(L, 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);  /* _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;
+  if (lua_getstack(L, 1, &ar) == 0 ||
+      lua_getinfo(L, "f", &ar) == 0 ||  /* get calling function */
+      lua_iscfunction(L, -1))
+    luaL_error(L, LUA_QL("module") " not called from a Lua function");
+  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 = rb->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 loaded = lua_gettop(L) + 1;  /* index of _LOADED table */
+  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
+  lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */
+  if (!lua_istable(L, -1)) {  /* not found? */
+    lua_pop(L, 1);  /* remove previous result */
+    /* try global variable (and create one if it does not exist) */
+    if (luaL_findtable(L, LUA_GLOBALSINDEX, modname, 1) != NULL)
+      return luaL_error(L, "name conflict for module " LUA_QS, modname);
+    lua_pushvalue(L, -1);
+    lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new table */
+  }
+  /* 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);
+    modinit(L, modname);
+  }
+  lua_pushvalue(L, -1);
+  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_createtable(L, 0, 1); /* 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;
+}
+
+
+/* }====================================================== */
+
+
+
+/* auxiliary mark (for internal use) */
+#define AUXMARK     "\1"
+
+static void setpath (lua_State *L, const char *fieldname, const char *envname,
+                                   const char *def) {
+  (void)envname;
+  lua_pushstring(L, def);  /* use default */
+  setprogdir(L);
+  lua_setfield(L, -2, fieldname);
+}
+
+
+static const luaL_Reg pk_funcs[] = {
+  {"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_Lua, NULL};
+
+
+LUALIB_API int luaopen_package (lua_State *L) {
+  int i;
+  /* create new type _LOADLIB */
+  luaL_newmetatable(L, "_LOADLIB");
+  /* create `package' table */
+  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_replace(L, LUA_ENVIRONINDEX);
+  /* create `loaders' table */
+  lua_createtable(L, 0, sizeof(loaders)/sizeof(loaders[0]) - 1);
+  /* fill it with pre-defined loaders */
+  for (i=0; loaders[i] != NULL; i++) {
+    lua_pushcfunction(L, loaders[i]);
+    lua_rawseti(L, -2, i+1);
+  }
+  lua_setfield(L, -2, "loaders");  /* put it in field `loaders' */
+  setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);  /* set field `path' */
+  /* store config information */
+  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
+                     LUA_EXECDIR "\n" LUA_IGMARK);
+  lua_setfield(L, -2, "config");
+  /* set field `loaded' */
+  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);
+  lua_setfield(L, -2, "loaded");
+  /* set field `preload' */
+  lua_newtable(L);
+  lua_setfield(L, -2, "preload");
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  luaL_register(L, NULL, ll_funcs);  /* open lib into global table */
+  lua_pop(L, 1);
+  return 1;  /* return 'package' table */
+}
+

apps/plugins/lua/rockconf.h

@@ -28,6 +28,9 @@
 #undef LUAI_TRY
 #undef luai_jmpbuf
 
+#undef LUA_PATH_DEFAULT
+#define LUA_PATH_DEFAULT  "./?.lua;" VIEWERS_DIR"/?.lua;"
+
 #ifndef SIMULATOR
 #include "../../codecs/lib/setjmp.h"
 #else

apps/plugins/lua/rocklib.c

@@ -866,13 +866,33 @@ RB_WRAP(read_bmp_file)
 RB_WRAP(current_path)
 {
     char buffer[MAX_PATH];
-    if(get_cur_path(L, buffer, sizeof(buffer)))
+    lua_Debug ar;
+
+    if(lua_getstack(L, 1, &ar))
     {
-        lua_pushstring(L, buffer);
-        return 1;
+        /* Try determining the base path of the current Lua chunk
+            and write it to dest. */
+        lua_getinfo(L, "S", &ar);
+
+        char* curfile = (char*) &ar.source[1];
+        char* pos = rb->strrchr(curfile, '/');
+        if(pos != NULL)
+        {
+            unsigned int len = (unsigned int)(pos - curfile);
+            len = len + 1 > sizeof(buffer) ? sizeof(buffer) - 1 : len;
+
+            if(len > 0)
+                memcpy(buffer, curfile, len);
+
+            buffer[len] = '/';
+            buffer[len+1] = '\0';
+
+            lua_pushstring(L, buffer);
+            return 1;
+        }
     }
-    else
-        return 0;
+
+    return 0;
 }
 
 #define R(NAME) {#NAME, rock_##NAME}

apps/plugins/lua/rocklua.c

@@ -36,6 +36,7 @@ static const luaL_Reg lualibs[] = {
   {LUA_OSLIBNAME,   luaopen_os},
   {LUA_ROCKLIBNAME, luaopen_rock},
   {LUA_BITLIBNAME,  luaopen_bit},
+  {LUA_LOADLIBNAME, luaopen_package},
   {NULL, NULL}
 };