apps/plugins/lua/rocklua.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2008 Dan Everton (safetydan)
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #include "plugin.h"
  23 #include "lib/pluginlib_exit.h"
  24 #include "lua.h"
  25 #include "lauxlib.h"
  26 #include "lualib.h"
  27 #include "rocklib.h"
  28 #include "rockmalloc.h"
  29 #include "luadir.h"
  30
  31 PLUGIN_HEADER
  32
  33 static const luaL_Reg lualibs[] = {
  34   {"",              luaopen_base},
  35   {LUA_TABLIBNAME,  luaopen_table},
  36   {LUA_STRLIBNAME,  luaopen_string},
  37   {LUA_OSLIBNAME,   luaopen_os},
  38   {LUA_ROCKLIBNAME, luaopen_rock},
  39   {LUA_BITLIBNAME,  luaopen_bit},
  40   {LUA_IOLIBNAME,   luaopen_io},
  41   {LUA_LOADLIBNAME, luaopen_package},
  42   {LUA_MATHLIBNAME, luaopen_math},
  43   {LUA_DIRLIBNAME,  luaopen_luadir},
  44   {NULL, NULL}
  45 };
  46
  47 static void rocklua_openlibs(lua_State *L) {
  48   const luaL_Reg *lib = lualibs;
  49   for (; lib->func; lib++) {
  50     lua_pushcfunction(L, lib->func);
  51     lua_pushstring(L, lib->name);
  52     lua_call(L, 1, 0);
  53   }
  54 }
  55
  56 /* ldlib.c */
  57 static lua_State *getthread (lua_State *L, int *arg) {
  58   if (lua_isthread(L, 1)) {
  59     *arg = 1;
  60     return lua_tothread(L, 1);
  61   }
  62   else {
  63     *arg = 0;
  64     return L;
  65   }
  66 }
  67
  68 #define LEVELS1 12      /* size of the first part of the stack */
  69 #define LEVELS2 10      /* size of the second part of the stack */
  70
  71 static int db_errorfb (lua_State *L) {
  72   int level;
  73   int firstpart = 1;  /* still before eventual `...' */
  74   int arg;
  75   lua_State *L1 = getthread(L, &arg);
  76   lua_Debug ar;
  77   if (lua_isnumber(L, arg+2)) {
  78     level = (int)lua_tointeger(L, arg+2);
  79     lua_pop(L, 1);
  80   }
  81   else
  82     level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */
  83   if (lua_gettop(L) == arg)
  84     lua_pushliteral(L, "");
  85   else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
  86   else lua_pushliteral(L, "\n");
  87   lua_pushliteral(L, "stack traceback:");
  88   while (lua_getstack(L1, level++, &ar)) {
  89     if (level > LEVELS1 && firstpart) {
  90       /* no more than `LEVELS2' more levels? */
  91       if (!lua_getstack(L1, level+LEVELS2, &ar))
  92         level--;  /* keep going */
  93       else {
  94         lua_pushliteral(L, "\n\t...");  /* too many levels */
  95         while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */
  96           level++;
  97       }
  98       firstpart = 0;
  99       continue;
 100     }
 101     lua_pushliteral(L, "\n\t");
 102     lua_getinfo(L1, "Snl", &ar);
 103     lua_pushfstring(L, "%s:", ar.short_src);
 104     if (ar.currentline > 0)
 105       lua_pushfstring(L, "%d:", ar.currentline);
 106     if (*ar.namewhat != '\0')  /* is there a name? */
 107         lua_pushfstring(L, " in function " LUA_QS, ar.name);
 108     else {
 109       if (*ar.what == 'm')  /* main? */
 110         lua_pushfstring(L, " in main chunk");
 111       else if (*ar.what == 'C' || *ar.what == 't')
 112         lua_pushliteral(L, " ?");  /* C function or tail call */
 113       else
 114         lua_pushfstring(L, " in function <%s:%d>",
 115                            ar.short_src, ar.linedefined);
 116     }
 117     lua_concat(L, lua_gettop(L) - arg);
 118   }
 119   lua_concat(L, lua_gettop(L) - arg);
 120   return 1;
 121 }
 122
 123 /* lua.c */
 124 static int traceback (lua_State *L) {
 125   lua_pushcfunction(L, db_errorfb);
 126   lua_pushvalue(L, 1);  /* pass error message */
 127   lua_pushinteger(L, 2);  /* skip this function and traceback */
 128   lua_call(L, 2, 1);  /* call debug.traceback */
 129   return 1;
 130 }
 131
 132 static int docall (lua_State *L) {
 133   int status;
 134   int base = lua_gettop(L);  /* function index */
 135   lua_pushcfunction(L, traceback);  /* push traceback function */
 136   lua_insert(L, base);  /* put it under chunk and args */
 137   status = lua_pcall(L, 0, 0, base);
 138   lua_remove(L, base);  /* remove traceback function */
 139   /* force a complete garbage collection in case of errors */
 140   if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0);
 141   return status;
 142 }
 143
 144
 145 /***************** Plugin Entry Point *****************/
 146 enum plugin_status plugin_start(const void* parameter)
 147 {
 148     const char* filename;
 149     int status;
 150
 151     PLUGINLIB_EXIT_INIT
 152
 153     if (parameter == NULL)
 154     {
 155         rb->splash(HZ, "Play a .lua file!");
 156         return PLUGIN_ERROR;
 157     }
 158     else
 159     {
 160         filename = (char*) parameter;
 161
 162         lua_State *L = luaL_newstate();
 163
 164         rocklua_openlibs(L);
 165         status = luaL_loadfile(L, filename);
 166         if (!status) {
 167             rb->lcd_clear_display();
 168             status = docall(L);
 169         }
 170
 171         dlmalloc_stats();
 172
 173         if (status) {
 174             DEBUGF("%s\n", lua_tostring(L, -1));
 175             rb->splashf(5 * HZ, "%s", lua_tostring(L, -1));
 176             lua_pop(L, 1);
 177         }
 178
 179         lua_close(L);
 180     }
 181
 182     return PLUGIN_OK;
 183 }
 184