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
  30 PLUGIN_HEADER
  31
  32 static const luaL_Reg lualibs[] = {
  33   {"",              luaopen_base},
  34   {LUA_TABLIBNAME,  luaopen_table},
  35   {LUA_STRLIBNAME,  luaopen_string},
  36   {LUA_OSLIBNAME,   luaopen_os},
  37   {LUA_ROCKLIBNAME, luaopen_rock},
  38   {LUA_BITLIBNAME,  luaopen_bit},
  39   {LUA_IOLIBNAME,   luaopen_io},
  40   {LUA_LOADLIBNAME, luaopen_package},
  41   {LUA_MATHLIBNAME, luaopen_math},
  42   {NULL, NULL}
  43 };
  44
  45 static void rocklua_openlibs(lua_State *L) {
  46   const luaL_Reg *lib = lualibs;
  47   for (; lib->func; lib++) {
  48     lua_pushcfunction(L, lib->func);
  49     lua_pushstring(L, lib->name);
  50     lua_call(L, 1, 0);
  51   }
  52 }
  53
  54 /* ldlib.c */
  55 static lua_State *getthread (lua_State *L, int *arg) {
  56   if (lua_isthread(L, 1)) {
  57     *arg = 1;
  58     return lua_tothread(L, 1);
  59   }
  60   else {
  61     *arg = 0;
  62     return L;
  63   }
  64 }
  65
  66 #define LEVELS1 12      /* size of the first part of the stack */
  67 #define LEVELS2 10      /* size of the second part of the stack */
  68
  69 static int db_errorfb (lua_State *L) {
  70   int level;
  71   int firstpart = 1;  /* still before eventual `...' */
  72   int arg;
  73   lua_State *L1 = getthread(L, &arg);
  74   lua_Debug ar;
  75   if (lua_isnumber(L, arg+2)) {
  76     level = (int)lua_tointeger(L, arg+2);
  77     lua_pop(L, 1);
  78   }
  79   else
  80     level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */
  81   if (lua_gettop(L) == arg)
  82     lua_pushliteral(L, "");
  83   else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
  84   else lua_pushliteral(L, "\n");
  85   lua_pushliteral(L, "stack traceback:");
  86   while (lua_getstack(L1, level++, &ar)) {
  87     if (level > LEVELS1 && firstpart) {
  88       /* no more than `LEVELS2' more levels? */
  89       if (!lua_getstack(L1, level+LEVELS2, &ar))
  90         level--;  /* keep going */
  91       else {
  92         lua_pushliteral(L, "\n\t...");  /* too many levels */
  93         while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */
  94           level++;
  95       }
  96       firstpart = 0;
  97       continue;
  98     }
  99     lua_pushliteral(L, "\n\t");
 100     lua_getinfo(L1, "Snl", &ar);
 101     lua_pushfstring(L, "%s:", ar.short_src);
 102     if (ar.currentline > 0)
 103       lua_pushfstring(L, "%d:", ar.currentline);
 104     if (*ar.namewhat != '\0')  /* is there a name? */
 105         lua_pushfstring(L, " in function " LUA_QS, ar.name);
 106     else {
 107       if (*ar.what == 'm')  /* main? */
 108         lua_pushfstring(L, " in main chunk");
 109       else if (*ar.what == 'C' || *ar.what == 't')
 110         lua_pushliteral(L, " ?");  /* C function or tail call */
 111       else
 112         lua_pushfstring(L, " in function <%s:%d>",
 113                            ar.short_src, ar.linedefined);
 114     }
 115     lua_concat(L, lua_gettop(L) - arg);
 116   }
 117   lua_concat(L, lua_gettop(L) - arg);
 118   return 1;
 119 }
 120
 121 /* lua.c */
 122 static int traceback (lua_State *L) {
 123   lua_pushcfunction(L, db_errorfb);
 124   lua_pushvalue(L, 1);  /* pass error message */
 125   lua_pushinteger(L, 2);  /* skip this function and traceback */
 126   lua_call(L, 2, 1);  /* call debug.traceback */
 127   return 1;
 128 }
 129
 130 static int docall (lua_State *L) {
 131   int status;
 132   int base = lua_gettop(L);  /* function index */
 133   lua_pushcfunction(L, traceback);  /* push traceback function */
 134   lua_insert(L, base);  /* put it under chunk and args */
 135   status = lua_pcall(L, 0, 0, base);
 136   lua_remove(L, base);  /* remove traceback function */
 137   /* force a complete garbage collection in case of errors */
 138   if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0);
 139   return status;
 140 }
 141
 142
 143 /***************** Plugin Entry Point *****************/
 144 enum plugin_status plugin_start(const void* parameter)
 145 {
 146     const char* filename;
 147     int status;
 148
 149     PLUGINLIB_EXIT_INIT
 150
 151     if (parameter == NULL)
 152     {
 153         rb->splash(HZ, "Play a .lua file!");
 154         return PLUGIN_ERROR;
 155     }
 156     else
 157     {
 158         filename = (char*) parameter;
 159
 160         lua_State *L = luaL_newstate();
 161
 162         rocklua_openlibs(L);
 163         status = luaL_loadfile(L, filename);
 164         if (!status) {
 165             rb->lcd_clear_display();
 166             status = docall(L);
 167         }
 168
 169         dlmalloc_stats();
 170
 171         if (status) {
 172             DEBUGF("%s\n", lua_tostring(L, -1));
 173             rb->splashf(5 * HZ, "%s", lua_tostring(L, -1));
 174             lua_pop(L, 1);
 175         }
 176
 177         lua_close(L);
 178     }
 179
 180     return PLUGIN_OK;
 181 }
 182