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Split simgrid_lua.c in one source file per module
[simgrid.git] / src / bindings / lua / simgrid_lua.c
index faf9d44..b4b3763 100644 (file)
-/* SimGrid Lua bindings                                                     */
-
 /* Copyright (c) 2010. The SimGrid Team.
  * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
 
-#include <stdio.h>
-#include <lauxlib.h>
-#include <lualib.h>
-#include "msg/msg.h"
+/* SimGrid Lua bindings                                                     */
+
+#include "lua_private.h"
+#include "lua_state_cloner.h"
+#include "lua_utils.h"
 #include "xbt.h"
+#include "msg/msg.h"
+#include "simdag/simdag.h"
+#include "surf/surfxml_parse.h"
+#include "gras.h"
+#include <lauxlib.h>
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua, bindings, "Lua Bindings");
 
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua,bindings,"Lua Bindings");
+static lua_State* sglua_maestro_state;
 
-#define TASK_MODULE_NAME "simgrid.Task"
-#define HOST_MODULE_NAME "simgrid.Host"
-// Surf ( bypass XML )
-#define LINK_MODULE_NAME "simgrid.Link"
-#define ROUTE_MODULE_NAME "simgrid.Route"
-#undef BYPASS_MODEL
+int luaopen_simgrid(lua_State *L);
+static void sglua_register_c_functions(lua_State *L);
+static int run_lua_code(int argc, char **argv);
 
 /* ********************************************************************************* */
-/*                            helper functions                                       */
+/*                           lua_stub_generator functions                            */
 /* ********************************************************************************* */
 
-static void stackDump (const char *msg, lua_State *L) {
-  char buff[2048];
-  char *p=buff;
-  int i;
-  int top = lua_gettop(L);
-
-  fflush(stdout);
-  p+=sprintf(p,"STACK(top=%d): ",top);
-
-  for (i = 1; i <= top; i++) {  /* repeat for each level */
-    int t = lua_type(L, i);
-    switch (t) {
-
-    case LUA_TSTRING:  /* strings */
-      p+=sprintf(p,"`%s'", lua_tostring(L, i));
-      break;
+xbt_dict_t process_function_set;
+xbt_dynar_t process_list;
+xbt_dict_t machine_set;
+static s_process_t process;
 
-    case LUA_TBOOLEAN:  /* booleans */
-      p+=sprintf(p,lua_toboolean(L, i) ? "true" : "false");
-      break;
-
-    case LUA_TNUMBER:  /* numbers */
-      p+=sprintf(p,"%g", lua_tonumber(L, i));
-      break;
-
-    case LUA_TTABLE:
-      p+=sprintf(p, "Table");
-      break;
+void s_process_free(void *process)
+{
+  s_process_t *p = (s_process_t *) process;
+  int i;
+  for (i = 0; i < p->argc; i++)
+    free(p->argv[i]);
+  free(p->argv);
+  free(p->host);
+}
 
-    default:  /* other values */
-      p+=sprintf(p, "???");
-/*      if ((ptr = luaL_checkudata(L,i,TASK_MODULE_NAME))) {
-        p+=sprintf(p,"task");
-      } else {
-        p+=printf(p,"%s", lua_typename(L, t));
-      }*/
-      break;
+static int gras_add_process_function(lua_State * L)
+{
+  const char *arg;
+  const char *process_host = luaL_checkstring(L, 1);
+  const char *process_function = luaL_checkstring(L, 2);
+
+  if (xbt_dict_is_empty(machine_set)
+      || xbt_dict_is_empty(process_function_set)
+      || xbt_dynar_is_empty(process_list)) {
+    process_function_set = xbt_dict_new_homogeneous(NULL);
+    process_list = xbt_dynar_new(sizeof(s_process_t), s_process_free);
+    machine_set = xbt_dict_new_homogeneous(NULL);
+  }
 
-    }
-    p+=sprintf(p,"  ");  /* put a separator */
+  xbt_dict_set(machine_set, process_host, NULL, NULL);
+  xbt_dict_set(process_function_set, process_function, NULL, NULL);
+
+  process.argc = 1;
+  process.argv = xbt_new(char *, 1);
+  process.argv[0] = xbt_strdup(process_function);
+  process.host = strdup(process_host);
+
+  lua_pushnil(L);
+  while (lua_next(L, 3) != 0) {
+    arg = lua_tostring(L, -1);
+    process.argc++;
+    process.argv =
+        xbt_realloc(process.argv, (process.argc) * sizeof(char *));
+    process.argv[(process.argc) - 1] = xbt_strdup(arg);
+
+    XBT_DEBUG("index = %f , arg = %s \n", lua_tonumber(L, -2),
+           lua_tostring(L, -1));
+    lua_pop(L, 1);
   }
-  INFO2("%s%s",msg,buff);
+  lua_pop(L, 1);
+  //add to the process list
+  xbt_dynar_push(process_list, &process);
+  return 0;
 }
 
-/** @brief ensures that a userdata on the stack is a task and returns the pointer inside the userdata */
-static m_task_t checkTask (lua_State *L,int index) {
-  m_task_t *pi,tk;
-  luaL_checktype(L,index,LUA_TTABLE);
-  lua_getfield(L,index,"__simgrid_task");
-  pi = (m_task_t*)luaL_checkudata(L,-1,TASK_MODULE_NAME);
-  if(pi == NULL)
-        luaL_typerror(L,index,TASK_MODULE_NAME);
-  tk = *pi;
-  if(!tk)
-        luaL_error(L,"null Task");
-  lua_pop(L,1);
-  return  tk;
+static int gras_generate(lua_State * L)
+{
+  const char *project_name = luaL_checkstring(L, 1);
+  generate_sim(project_name);
+  generate_rl(project_name);
+  generate_makefile_local(project_name);
+  return 0;
 }
+
 /* ********************************************************************************* */
-/*                           wrapper functions                                       */
+/*                                  simgrid API                                      */
 /* ********************************************************************************* */
 
 /**
- * A task is either something to compute somewhere, or something to exchange between two hosts (or both).
- * It is defined by a computing amount and a message size.
+ * \brief Deploys your application.
+ * \param L a Lua state
+ * \return number of values returned to Lua
  *
+ * - Argument 1 (string): name of the deployment file to load
  */
+static int launch_application(lua_State* L) {
+
+  const char* file = luaL_checkstring(L, 1);
+  MSG_function_register_default(run_lua_code);
+  MSG_launch_application(file);
+  return 0;
+}
 
-/* *              * *
- * * Constructors * *
- * *              * */
 /**
- * Construct an new task with the specified processing amount and amount
- * of data needed.
+ * \brief Creates the platform.
+ * \param L a Lua state
+ * \return number of values returned to Lua
  *
- * @param name Task's name
- *
- * @param computeDuration      A value of the processing amount (in flop) needed to process the task.
- *                             If 0, then it cannot be executed with the execute() method.
- *                             This value has to be >= 0.
- *
- * @param messageSize          A value of amount of data (in bytes) needed to transfert this task.
- *                             If 0, then it cannot be transfered with the get() and put() methods.
- *                             This value has to be >= 0.
+ * - Argument 1 (string): name of the platform file to load
  */
-static int Task_new(lua_State* L) {
-         const char *name=luaL_checkstring(L,1);
-         int comp_size = luaL_checkint(L,2);
-         int msg_size = luaL_checkint(L,3);
-         INFO0("Creating task");
-         m_task_t msg_task = MSG_task_create(name,comp_size,msg_size,NULL);
-         lua_newtable (L); /* create a table, put the userdata on top of it */
-         m_task_t *lua_task = (m_task_t*)lua_newuserdata(L,sizeof(m_task_t));
-         *lua_task = msg_task;
-         luaL_getmetatable(L,TASK_MODULE_NAME);
-         lua_setmetatable(L,-2);
-         lua_setfield (L, -2, "__simgrid_task"); /* put the userdata as field of the table */
-         /* remove the args from the stack */
-         lua_remove(L,1);
-         lua_remove(L,1);
-         lua_remove(L,1);
-         return 1;
-}
+static int create_environment(lua_State* L) {
 
-static int Task_get_name(lua_State *L) {
-  m_task_t tk = checkTask(L,-1);
-  lua_pushstring(L,MSG_task_get_name(tk));
-  return 1;
+  const char* file = luaL_checkstring(L, 1);
+  XBT_DEBUG("Loading environment file %s", file);
+  MSG_create_environment(file);
+  return 0;
 }
 
-static int Task_computation_duration(lua_State *L){
-  m_task_t tk = checkTask(L,-1);
-  lua_pushnumber(L,MSG_task_get_compute_duration (tk));
-  return 1;
-}
+/**
+ * \brief Prints a log string with debug level.
+ * \param L a Lua state
+ * \return number of values returned to Lua
+ *
+ * - Argument 1 (string): the text to print
+ */
+static int debug(lua_State* L) {
 
-static int Task_execute(lua_State *L){
-  m_task_t tk = checkTask(L,-1);
-  int res = MSG_task_execute(tk);
-  lua_pushnumber(L,res);
-  return 1;
+  const char* str = luaL_checkstring(L, 1);
+  XBT_DEBUG("%s", str);
+  return 0;
 }
 
-static int Task_destroy(lua_State *L) {
-  m_task_t tk = checkTask(L,-1);
-  int res = MSG_task_destroy(tk);
-  lua_pushnumber(L,res);
-  return 1;
-}
+/**
+ * \brief Prints a log string with info level.
+ * \param L a Lua state
+ * \return number of values returned to Lua
+ *
+ * - Argument 1 (string): the text to print
+ */
+static int info(lua_State* L) {
 
-static int Task_send(lua_State *L)  {
-  //stackDump("send ",L);
-  m_task_t tk = checkTask(L,-2);
-  const char *mailbox = luaL_checkstring(L,-1);
-  lua_pop(L,1); // remove the string so that the task is on top of it
-  MSG_task_set_data(tk,L); // Copy my stack into the task, so that the receiver can copy the lua task directly
-  MSG_error_t res = MSG_task_send(tk,mailbox);
-  while (MSG_task_get_data(tk)!=NULL) // Don't mess up with my stack: the receiver didn't copy the data yet
-    MSG_process_sleep(0); // yield
-
-  if (res != MSG_OK) switch(res) {
-    case MSG_TIMEOUT :
-      ERROR0("MSG_task_send failed : Timeout");
-      break;
-    case MSG_TRANSFER_FAILURE :
-      ERROR0("MSG_task_send failed : Transfer Failure");
-      break;
-    case MSG_HOST_FAILURE :
-      ERROR0("MSG_task_send failed : Host Failure ");
-      break;
-    default :
-      ERROR0("MSG_task_send failed : Unexpected error , please report this bug");
-      break;
-    }
+  const char* str = luaL_checkstring(L, 1);
+  XBT_INFO("%s", str);
   return 0;
 }
 
-static int Task_recv(lua_State *L)  {
-  m_task_t tk = NULL;
-  const char *mailbox = luaL_checkstring(L,-1);
-  MSG_error_t res = MSG_task_receive(&tk,mailbox);
-
-  lua_State *sender_stack = MSG_task_get_data(tk);
-  lua_xmove(sender_stack,L,1); // copy the data directly from sender's stack
-  MSG_task_set_data(tk,NULL);
-
-  if(res != MSG_OK) switch(res){
-         case MSG_TIMEOUT :
-                 ERROR0("MSG_task_receive failed : Timeout");
-                 break;
-         case MSG_TRANSFER_FAILURE :
-                 ERROR0("MSG_task_receive failed : Transfer Failure");
-                 break;
-         case MSG_HOST_FAILURE :
-                 ERROR0("MSG_task_receive failed : Host Failure ");
-                 break;
-         default :
-                 ERROR0("MSG_task_receive failed : Unexpected error , please report this bug");
-                 break;
-                 }
-
-  return 1;
-}
+/**
+ * \brief Runs your application.
+ * \param L a Lua state
+ * \return number of values returned to Lua
+ */
+static int run(lua_State*  L) {
 
-static const luaL_reg Task_methods[] = {
-    {"new",   Task_new},
-    {"name",  Task_get_name},
-    {"computation_duration",  Task_computation_duration},
-    {"execute", Task_execute},
-    {"destroy", Task_destroy},
-    {"send",    Task_send},
-    {"recv",    Task_recv},
-    {0,0}
-};
-static int Task_gc(lua_State *L) {
-  m_task_t tk=checkTask(L,-1);
-  if (tk) MSG_task_destroy(tk);
+  MSG_main();
   return 0;
 }
 
-static int Task_tostring(lua_State *L) {
-  lua_pushfstring(L, "Task :%p",lua_touserdata(L,1));
+/**
+ * \brief Returns the current simulated time.
+ * \param L a Lua state
+ * \return number of values returned to Lua
+ *
+ * - Return value (number): the simulated time
+ */
+static int get_clock(lua_State* L) {
+
+  lua_pushnumber(L, MSG_get_clock());
   return 1;
 }
 
-static const luaL_reg Task_meta[] = {
-    {"__gc",  Task_gc},
-    {"__tostring",  Task_tostring},
-    {0,0}
-};
-
 /**
- * Host
+ * \brief Cleans the simulation.
+ * \param L a Lua state
+ * \return number of values returned to Lua
  */
-static m_host_t checkHost (lua_State *L,int index) {
-  m_host_t *pi,ht;
-  luaL_checktype(L,index,LUA_TTABLE);
-  lua_getfield(L,index,"__simgrid_host");
-  pi = (m_host_t*)luaL_checkudata(L,-1,HOST_MODULE_NAME);
-  if(pi == NULL)
-        luaL_typerror(L,index,HOST_MODULE_NAME);
-  ht = *pi;
-  if(!ht)
-        luaL_error(L,"null Host");
-  lua_pop(L,1);
-  return  ht;
+static int simgrid_gc(lua_State * L)
+{
+  MSG_clean();
+  return 0;
 }
 
-static int Host_get_by_name(lua_State *L)
+/*
+ * Register platform for MSG
+ */
+static int msg_register_platform(lua_State * L)
 {
-       const char *name=luaL_checkstring(L,1);
-       DEBUG0("Getting Host from name...");
-       m_host_t msg_host = MSG_get_host_by_name(name);
-       if (!msg_host)
-               {
-               luaL_error(L,"null Host : MSG_get_host_by_name failled");
-               }
-    lua_newtable (L); /* create a table, put the userdata on top of it */
-       m_host_t *lua_host = (m_host_t*)lua_newuserdata(L,sizeof(m_host_t));
-       *lua_host = msg_host;
-       luaL_getmetatable(L,HOST_MODULE_NAME);
-       lua_setmetatable(L,-2);
-       lua_setfield (L, -2, "__simgrid_host"); /* put the userdata as field of the table */
-       /* remove the args from the stack */
-       lua_remove(L,1);
-       return 1;
+  /* Tell Simgrid we dont wanna use its parser */
+  //surf_parse = console_parse_platform;
+  surf_parse_reset_callbacks();
+  MSG_create_environment(NULL);
+  return 0;
 }
 
+/*
+ * Register platform for Simdag
+ */
 
-static int Host_get_name(lua_State *L) {
-  m_host_t ht = checkHost(L,-1);
-  lua_pushstring(L,MSG_host_get_name(ht));
-  return 1;
-}
-
-static int Host_number(lua_State *L) {
-  lua_pushnumber(L,MSG_get_host_number());
-  return 1;
+static int sd_register_platform(lua_State * L)
+{
+  //surf_parse = console_parse_platform_wsL07;
+  surf_parse_reset_callbacks();
+  SD_create_environment(NULL);
+  return 0;
 }
 
-static int Host_at(lua_State *L)
+/*
+ * Register platform for gras
+ */
+static int gras_register_platform(lua_State * L)
 {
-       int index = luaL_checkinteger(L,1);
-       m_host_t host = MSG_get_host_table()[index-1]; // lua indexing start by 1 (lua[1] <=> C[0])
-       lua_newtable (L); /* create a table, put the userdata on top of it */
-       m_host_t *lua_host = (m_host_t*)lua_newuserdata(L,sizeof(m_host_t));
-       *lua_host = host;
-       luaL_getmetatable(L,HOST_MODULE_NAME);
-       lua_setmetatable(L,-2);
-       lua_setfield (L, -2, "__simgrid_host"); /* put the userdata as field of the table */
-       return 1;
-
+  //surf_parse = console_parse_platform;
+  surf_parse_reset_callbacks();
+  gras_create_environment(NULL);
+  return 0;
 }
 
-/*****************************************************************************************
-                                                            * BYPASS XML SURF Methods *
-                                                                ***************************
-                                                                ***************************
-******************************************************************************************/
-#include "surf/surfxml_parse.h" /* to override surf_parse and bypass the parser */
-#include "surf/surf_private.h"
-typedef struct t_host_attr
-{
-       //platform attribute
-       // Mandatory attributes
-       const char* id;
-       double power_peak;
-       // Optional attributes
-       double power_scale;
-       const char *power_trace;
-       int state_initial;
-       const char *state_trace;
-       //deployment attribute
-       const char* function;
-       xbt_dynar_t args_list;
-}host_attr,*p_host_attr;
-
-typedef struct t_link_attr
+/**
+ * Register applicaiton for MSG
+ */
+static int msg_register_application(lua_State * L)
 {
-       const char* id;
-       double bandwidth;
-       double latency;
-}link_attr,*p_link_attr;
+  MSG_function_register_default(run_lua_code);
+  //surf_parse = console_parse_application;
+  MSG_launch_application(NULL);
+  return 0;
+}
 
-typedef struct t_route_attr
+/*
+ * Register application for gras
+ */
+static int gras_register_application(lua_State * L)
 {
-       const char *src_id;
-       const char *dest_id;
-       xbt_dynar_t links_id;
-
-}route_attr,*p_route_attr;
-
-//using xbt_dynar_t :
-static xbt_dynar_t host_list_d ;
-static xbt_dynar_t link_list_d ;
-static xbt_dynar_t route_list_d ;
-
-
-//create resource
-
-/*FIXME : still have to use a dictionary as argument make it possible to
-consider some arguments as optional and removes the importance of the
-parameter order */
+  gras_function_register_default(run_lua_code);
+  //surf_parse = console_parse_application;
+  gras_launch_application(NULL);
+  return 0;
+}
 
-static void create_host(const char* id,double power_peak,double power_sc,
-                                               const char* power_tr,int state_init,
-                                               const char* state_tr)
-{
+static const luaL_Reg simgrid_functions[] = {
+  {"create_environment", create_environment},
+  {"launch_application", launch_application},
+  {"debug", debug},
+  {"info", info},
+  {"run", run},
+  {"get_clock", get_clock},
+  /* short names */
+  {"platform", create_environment},
+  {"application", launch_application},
+  /* methods to bypass XML parser */
+  {"msg_register_platform", msg_register_platform},
+  {"sd_register_platform", sd_register_platform},
+  {"msg_register_application", msg_register_application},
+  {"gras_register_platform", gras_register_platform},
+  {"gras_register_application", gras_register_application},
+  /* gras sub generator method */
+  {"gras_set_process_function", gras_add_process_function},
+  {"gras_generate", gras_generate},
+  {NULL, NULL}
+};
 
-       double power_scale = 1.0;
-       tmgr_trace_t power_trace = NULL;
-       e_surf_resource_state_t state_initial;
-       tmgr_trace_t state_trace;
-       if(power_sc) // !=0
-               power_scale = power_sc;
-       if (state_init == 1)
-               state_initial = SURF_RESOURCE_ON;
-       else
-               state_init = SURF_RESOURCE_OFF;
-       if(power_tr)
-               power_trace = tmgr_trace_new(power_tr);
-       else
-               power_trace = tmgr_trace_new("");
-       if(state_tr)
-               state_trace = tmgr_trace_new(state_tr);
-       else
-               state_trace = tmgr_trace_new("");
-       current_property_set = xbt_dict_new();
-       surf_host_create_resource(xbt_strdup(id), power_peak, power_scale,
-                                              power_trace, state_initial, state_trace, current_property_set);
+/* ********************************************************************************* */
+/*                           module management functions                             */
+/* ********************************************************************************* */
 
-}
+#define LUA_MAX_ARGS_COUNT 10   /* maximum amount of arguments we can get from lua on command line */
 
-static int Host_new(lua_State *L)
+/**
+ * \brief Opens the simgrid Lua module.
+ *
+ * This function is called automatically by the Lua interpreter when some
+ * Lua code requires the "simgrid" module.
+ *
+ * \param L the Lua state
+ */
+int luaopen_simgrid(lua_State *L)
 {
+  XBT_DEBUG("luaopen_simgrid *****");
 
-       if(xbt_dynar_is_empty(host_list_d))
-               host_list_d = xbt_dynar_new(sizeof(p_host_attr), &xbt_free_ref);
-
-       p_host_attr host;
-       const char * id;
-       const char *power_trace;
-       const char *state_trace;
-       double power,power_scale;
-       int state_initial;
-       //get values from the table passed as argument
-    if (lua_istable(L,-1)) {
-
-            // get Id Value
-            lua_pushstring(L,"id");
-            lua_gettable(L, -2 );
-            id = lua_tostring(L,-1);
-            lua_pop(L,1);
-
-            // get power value
-            lua_pushstring(L,"power");
-            lua_gettable(L, -2 );
-            power = lua_tonumber(L,-1);
-            lua_pop(L,1);
-
-            //get power_scale
-            lua_pushstring(L,"power_scale");
-            lua_gettable(L, -2 );
-            power_scale = lua_tonumber(L,-1);
-            lua_pop(L,1);
-
-            //get power_trace
-            lua_pushstring(L,"power_trace");
-            lua_gettable(L, -2 );
-            power_trace = lua_tostring(L,-1);
-            lua_pop(L,1);
-
-            //get state initial
-            lua_pushstring(L,"state_initial");
-            lua_gettable(L, -2 );
-            state_initial = lua_tonumber(L,-1);
-            lua_pop(L,1);
-
-            //get trace state
-            lua_pushstring(L,"state_trace");
-            lua_gettable(L, -2 );
-            state_trace = lua_tostring(L,-1);
-            lua_pop(L,1);
-
-    } else {
-            ERROR0("Bad Arguments to create host, Should be a table with named arguments");
-            return -1;
+  /* Get the command line arguments from the lua interpreter */
+  char **argv = malloc(sizeof(char *) * LUA_MAX_ARGS_COUNT);
+  int argc = 1;
+  argv[0] = (char *) "/usr/bin/lua";    /* Lie on the argv[0] so that the stack dumping facilities find the right binary. FIXME: what if lua is not in that location? */
+
+  lua_getglobal(L, "arg");
+  /* if arg is a null value, it means we use lua only as a script to init platform
+   * else it should be a table and then take arg in consideration
+   */
+  if (lua_istable(L, -1)) {
+    int done = 0;
+    while (!done) {
+      argc++;
+      lua_pushinteger(L, argc - 2);
+      lua_gettable(L, -2);
+      if (lua_isnil(L, -1)) {
+        done = 1;
+      } else {
+        xbt_assert(lua_isstring(L, -1),
+                    "argv[%d] got from lua is no string", argc - 1);
+        xbt_assert(argc < LUA_MAX_ARGS_COUNT,
+                    "Too many arguments, please increase LUA_MAX_ARGS_COUNT in %s before recompiling SimGrid if you insist on having more than %d args on command line",
+                    __FILE__, LUA_MAX_ARGS_COUNT - 1);
+        argv[argc - 1] = (char *) luaL_checkstring(L, -1);
+        lua_pop(L, 1);
+        XBT_DEBUG("Got command line argument %s from lua", argv[argc - 1]);
+      }
     }
+    argv[argc--] = NULL;
 
-           host = malloc(sizeof(host_attr));
-               host->id = id;
-               host->power_peak = power;
-               host->power_scale = power_scale;
-               host->power_trace = power_trace;
-               host->state_initial = state_initial;
-               host->state_trace = state_trace;
-               host->function = NULL;
-               xbt_dynar_push(host_list_d, &host);
-
-    return 0;
-
-}
+    /* Initialize the MSG core */
+    MSG_global_init(&argc, argv);
+    XBT_DEBUG("Still %d arguments on command line", argc); // FIXME: update the lua's arg table to reflect the changes from SimGrid
+  }
 
+  /* Keep the context mechanism informed of our lua world today */
+  sglua_maestro_state = L;
 
-static int Link_new(lua_State *L) // (id,bandwidth,latency)
-{
-       if(xbt_dynar_is_empty(link_list_d))
-               link_list_d = xbt_dynar_new(sizeof(p_link_attr), &xbt_free_ref);
-
-       const char* id;
-       double bandwidth,latency;
-       //get values from the table passed as argument
-       if (lua_istable(L,-1)) {
-                   // get Id Value
-                   lua_pushstring(L,"id");
-                   lua_gettable(L, -2 );
-                   id = lua_tostring(L,-1);
-                   lua_pop(L,1);
-
-                   // get bandwidth value
-                   lua_pushstring(L,"bandwidth");
-                   lua_gettable(L, -2 );
-                   bandwidth = lua_tonumber(L,-1);
-                   lua_pop(L,1);
-
-                   //get latency value
-                   lua_pushstring(L,"latency");
-                   lua_gettable(L, -2 );
-                   latency = lua_tonumber(L,-1);
-                   lua_pop(L,1);
-
-           } else {
-                   ERROR0("Bad Arguments to create link, Should be a table with named arguments");
-                   return -1;
-           }
-
-       p_link_attr link = malloc(sizeof(link_attr));
-       link->id = id;
-       link->bandwidth = bandwidth;
-       link->latency = latency;
-       xbt_dynar_push(link_list_d,&link);
-       return 0;
-}
+  /* initialize access to my tables by children Lua states */
+  lua_newtable(L);
+  lua_setfield(L, LUA_REGISTRYINDEX, "simgrid.maestro_tables");
 
-static int Route_new(lua_State *L) // (src_id,dest_id,links_number,link_table)
-{
-       if(xbt_dynar_is_empty(route_list_d))
-               route_list_d = xbt_dynar_new(sizeof(p_route_attr), &xbt_free_ref);
-    int i;
-       const char * link_id;
-       p_route_attr route = malloc(sizeof(route_attr));
-       route->src_id = luaL_checkstring(L,1);
-       route->dest_id = luaL_checkstring(L,2);
-       route->links_id = xbt_dynar_new(sizeof(char *), &xbt_free_ref);
-       lua_pushnil(L);
-       while (lua_next(L,3) != 0) {
-               link_id = lua_tostring(L, -1);
-               xbt_dynar_push(route->links_id, &link_id);
-           DEBUG2("index = %f , Link_id = %s \n",lua_tonumber(L, -2),lua_tostring(L, -1));
-           lua_pop(L, 1);
-       }
-       lua_pop(L, 1);
-
-       //add route to platform's route list
-       xbt_dynar_push(route_list_d,&route);
-       return 0;
-}
+  sglua_register_c_functions(L);
 
-static int Host_set_function(lua_State *L) //(host,function,nb_args,list_args)
-{
-       // look for the index of host in host_list
-       const char *host_id = luaL_checkstring(L,1);
-       const char* argument;
-       unsigned int i;
-       p_host_attr p_host;
-
-       xbt_dynar_foreach(host_list_d,i,p_host)
-       {
-               if(p_host->id == host_id)
-               {
-                       p_host->function = luaL_checkstring(L,2);
-                       p_host->args_list = xbt_dynar_new(sizeof(char *), &xbt_free_ref);
-                       // fill the args list
-                       lua_pushnil(L);
-                       int j = 0;
-                       while (lua_next(L,3) != 0) {
-                                       argument = lua_tostring(L, -1);
-                                       xbt_dynar_push(p_host->args_list, &argument);
-                                   DEBUG2("index = %f , Arg_id = %s \n",lua_tonumber(L, -2),lua_tostring(L, -1));
-                                   j++;
-                                   lua_pop(L, 1);
-                               }
-                       lua_pop(L, 1);
-                       return 0;
-               }
-       }
-       ERROR1("Host : %s Not Fount !!",host_id);
-       return 1;
+  return 1;
 }
 
-/*
- * surf parse bypass platform
+/**
+ * \brief Returns whether a Lua state is the maestro state.
+ * \param L a Lua state
+ * \return true if this is maestro
  */
-static int surf_parse_bypass_platform()
-{
-       char buffer[22];
-       unsigned int i,j;
-       char* link_id;
-
-       p_host_attr p_host;
-       p_link_attr p_link;
-       p_route_attr p_route;
-
-       static int AX_ptr = 0;
-       static int surfxml_bufferstack_size = 2048;
-
-         /* FIXME allocating memory for the buffer, I think 2kB should be enough */
-       surfxml_bufferstack = xbt_new0(char, surfxml_bufferstack_size);
-         /* <platform> */
-       SURFXML_BUFFER_SET(platform_version, "2");
-#ifndef BYPASS_CPU
-       SURFXML_START_TAG(platform);
-#endif
-
-       // Add Hosts
-       xbt_dynar_foreach(host_list_d,i,p_host)
-       {
-
-#ifdef BYPASS_MODEL
-               INFO0("Bypass_Cpu");
-               create_host(p_host->id,p_host->power_peak,p_host->power_scale,p_host->power_trace,
-                                       p_host->state_initial,p_host->state_trace);
-               //add to routing model host list
-               surf_route_add_host((char*)p_host->id);
-#else
-
-               SURFXML_BUFFER_SET(host_id,p_host->id);
-               sprintf(buffer,"%f",p_host->power_peak);
-               SURFXML_BUFFER_SET(host_power,buffer);
-               SURFXML_BUFFER_SET(host_availability, "1.0");
-               SURFXML_BUFFER_SET(host_availability_file, "");
-               A_surfxml_host_state = A_surfxml_host_state_ON;
-               SURFXML_BUFFER_SET(host_state_file, "");
-               SURFXML_BUFFER_SET(host_interference_send, "1.0");
-               SURFXML_BUFFER_SET(host_interference_recv, "1.0");
-               SURFXML_BUFFER_SET(host_interference_send_recv, "1.0");
-               SURFXML_BUFFER_SET(host_max_outgoing_rate, "-1.0");
-               SURFXML_START_TAG(host);
-               SURFXML_END_TAG(host);
-#endif
-       }
-
-       //add Links
-       INFO0("Start Adding Links");
-       xbt_dynar_foreach(link_list_d,i,p_link)
-       {
-#ifdef BYPASS_MODEL
-
-               INFO0("Bypass_Network");
-               surf_link_create_resouce((char*)p_link->id,p_link->bandwidth,p_link->latency);
-#else
-
-               SURFXML_BUFFER_SET(link_id,p_link->id);
-               sprintf(buffer,"%f",p_link->bandwidth);
-               SURFXML_BUFFER_SET(link_bandwidth,buffer);
-               SURFXML_BUFFER_SET(link_bandwidth_file, "");
-               sprintf(buffer,"%f",p_link->latency);
-               SURFXML_BUFFER_SET(link_latency,buffer);
-               SURFXML_BUFFER_SET(link_latency_file, "");
-               A_surfxml_link_state = A_surfxml_link_state_ON;
-               SURFXML_BUFFER_SET(link_state_file, "");
-               A_surfxml_link_sharing_policy = A_surfxml_link_sharing_policy_SHARED;
-               SURFXML_START_TAG(link);
-               SURFXML_END_TAG(link);
-#endif
-       }
-
-       // add route
-       INFO0("Start Adding routes");
-       xbt_dynar_foreach(route_list_d,i,p_route)
-       {
-#ifdef BYPASS_MODEL
-               surf_route_set_resource((char*)p_route->src_id,(char*)p_route->dest_id,p_route->links_id,0);
-#else
-
-               SURFXML_BUFFER_SET(route_src,p_route->src_id);
-               SURFXML_BUFFER_SET(route_dst,p_route->dest_id);
-               SURFXML_BUFFER_SET(route_impact_on_src, "0.0");
-               SURFXML_BUFFER_SET(route_impact_on_dst, "0.0");
-               SURFXML_BUFFER_SET(route_impact_on_src_with_other_recv, "0.0");
-               SURFXML_BUFFER_SET(route_impact_on_dst_with_other_send, "0.0");
-               SURFXML_START_TAG(route);
-
-               xbt_dynar_foreach(p_route->links_id,j,link_id)
-               {
-                       SURFXML_BUFFER_SET(link_c_ctn_id,link_id);
-                       SURFXML_START_TAG(link_c_ctn);
-                       SURFXML_END_TAG(link_c_ctn);
-
-               }
-
-               SURFXML_END_TAG(route);
-#endif
-       }
-       /* </platform> */
-       INFO0("Register Platform");
-#ifndef BYPASS_MODEL
-       SURFXML_END_TAG(platform);
-#endif
-
-       free(surfxml_bufferstack);
-       return 0; // must return 0 ?!!
-
+int sglua_is_maestro(lua_State* L) {
+  return L == sglua_maestro_state;
 }
-/*
- * surf parse bypass application
+
+/**
+ * \brief Returns the maestro state.
+ * \return the maestro Lua state
  */
-static int surf_parse_bypass_application()
-{
-         unsigned int i,j;
-         p_host_attr p_host;
-         char * arg;
-         static int AX_ptr;
-         static int surfxml_bufferstack_size = 2048;
-         /* FIXME ( should be manual )allocating memory to the buffer, I think 2MB should be enough */
-         surfxml_bufferstack = xbt_new0(char, surfxml_bufferstack_size);
-         /* <platform> */
-         SURFXML_BUFFER_SET(platform_version, "2");
-         SURFXML_START_TAG(platform);
-
-         xbt_dynar_foreach(host_list_d,i,p_host)
-         {
-                 if(p_host->function)
-                 {
-                         SURFXML_BUFFER_SET(process_host, p_host->id);
-                         SURFXML_BUFFER_SET(process_function, p_host->function);
-                         SURFXML_BUFFER_SET(process_start_time, "-1.0");
-                         SURFXML_BUFFER_SET(process_kill_time, "-1.0");
-                         SURFXML_START_TAG(process);
-                         //args
-                         xbt_dynar_foreach(p_host->args_list,j,arg)
-                         {
-                                 SURFXML_BUFFER_SET(argument_value,arg);
-                                 SURFXML_START_TAG(argument);
-                                 SURFXML_END_TAG(argument);
-                         }
-                         SURFXML_END_TAG(process);
-                 }
-         }
-         /* </platform> */
-         SURFXML_END_TAG(platform);
-         free(surfxml_bufferstack);
-         return 0;
+lua_State* sglua_get_maestro(void) {
+  return sglua_maestro_state;
 }
 
-//***********Register Methods *******************************************//
-/*
- * Host Methods
+/**
+ * \brief Makes the core functions available to the Lua world.
+ * \param L a Lua world
  */
-static const luaL_reg Host_methods[] = {
-    {"getByName",   Host_get_by_name},
-    {"name",           Host_get_name},
-    {"number",         Host_number},
-    {"at",                     Host_at},
-    // Bypass XML Methods
-    {"new",                    Host_new},
-    {"setFunction",    Host_set_function},
-    {0,0}
-};
-
-static int Host_gc(lua_State *L)
+static void sglua_register_core_functions(lua_State *L)
 {
-  m_host_t ht = checkHost(L,-1);
-  if (ht) ht = NULL;
-  return 0;
+  /* register the core C functions to lua */
+  luaL_register(L, "simgrid", simgrid_functions);
+                                  /* simgrid */
+
+  /* set a finalizer that cleans simgrid, by adding to the simgrid module a
+   * dummy userdata whose __gc metamethod calls MSG_clean() */
+  lua_newuserdata(L, sizeof(void*));
+                                  /* simgrid udata */
+  lua_newtable(L);
+                                  /* simgrid udata mt */
+  lua_pushcfunction(L, simgrid_gc);
+                                  /* simgrid udata mt simgrid_gc */
+  lua_setfield(L, -2, "__gc");
+                                  /* simgrid udata mt */
+  lua_setmetatable(L, -2);
+                                  /* simgrid udata */
+  lua_setfield(L, -2, "__simgrid_loaded");
+                                  /* simgrid */
+  lua_pop(L, 1);
+                                  /* -- */
 }
 
-static int Host_tostring(lua_State *L)
+/**
+ * \brief Creates the simgrid module and make it available to Lua.
+ * \param L a Lua world
+ */
+static void sglua_register_c_functions(lua_State *L)
 {
-  lua_pushfstring(L,"Host :%p",lua_touserdata(L,1));
-  return 1;
+  sglua_register_core_functions(L);
+  sglua_register_task_functions(L);
+  sglua_register_comm_functions(L);
+  sglua_register_host_functions(L);
+  sglua_register_process_functions(L);
+  sglua_register_platf_functions(L);
 }
 
-static const luaL_reg Host_meta[] = {
-    {"__gc",  Host_gc},
-    {"__tostring",  Host_tostring},
-    {0,0}
-};
-
-/*
- * Link Methods
- */
-static const luaL_reg Link_methods[] = {
-    {"new",Link_new},
-    {0,0}
-};
-/*
- * Route Methods
- */
-static const luaL_reg Route_methods[] ={
-   {"new",Route_new},
-   {0,0}
-};
-
-/*
- * Environment related
+/**
+ * \brief Runs a Lua function as a new simulated process.
+ * \param argc number of arguments of the function
+ * \param argv name of the Lua function and array of its arguments
+ * \return result of the function
  */
+static int run_lua_code(int argc, char **argv)
+{
+  XBT_DEBUG("Run lua code %s", argv[0]);
 
-extern lua_State *simgrid_lua_state;
-
-static int run_lua_code(int argc,char **argv) {
-  DEBUG1("Run lua code %s",argv[0]);
-  lua_State *L = lua_newthread(simgrid_lua_state);
-  int ref = luaL_ref(simgrid_lua_state, LUA_REGISTRYINDEX); // protect the thread from being garbage collected
-  int res = 1;
+  /* create a new state, getting globals from maestro */
+  lua_State *L = sglua_clone_maestro();
+  MSG_process_set_data(MSG_process_self(), L);
 
-  /* Start the co-routine */
-  lua_getglobal(L,argv[0]);
-  xbt_assert1(lua_isfunction(L,-1),
-      "The lua function %s does not seem to exist",argv[0]);
+  /* start the function */
+  lua_getglobal(L, argv[0]);
+  xbt_assert(lua_isfunction(L, -1),
+              "There is no Lua function with name `%s'", argv[0]);
 
-  // push arguments onto the stack
+  /* push arguments onto the stack */
   int i;
-  for(i=1;i<argc;i++)
-    lua_pushstring(L,argv[i]);
+  for (i = 1; i < argc; i++)
+    lua_pushstring(L, argv[i]);
 
-  // Call the function (in resume)
-  xbt_assert2(lua_pcall(L, argc-1, 1, 0) == 0,
-    "error running function `%s': %s",argv[0], lua_tostring(L, -1));
+  /* call the function */
+  _XBT_GNUC_UNUSED int err;
+  err = lua_pcall(L, argc - 1, 1, 0);
+  xbt_assert(err == 0, "Error running function `%s': %s", argv[0],
+              lua_tostring(L, -1));
 
   /* retrieve result */
+  int res = 1;
   if (lua_isnumber(L, -1)) {
     res = lua_tonumber(L, -1);
-    lua_pop(L, 1);  /* pop returned value */
-  }
-
-  // cleanups
-  luaL_unref(simgrid_lua_state,LUA_REGISTRYINDEX,ref );
-  DEBUG1("Execution of lua code %s is over", (argv ? argv[0] : "(null)"));
-  return res;
-}
-static int launch_application(lua_State *L) {
-  const char * file = luaL_checkstring(L,1);
-  MSG_function_register_default(run_lua_code);
-  MSG_launch_application(file);
-  return 0;
-}
-#include "simix/simix.h" //FIXME: KILLME when debugging on simix internals become useless
-static int create_environment(lua_State *L) {
-  const char *file = luaL_checkstring(L,1);
-  DEBUG1("Loading environment file %s",file);
-  MSG_create_environment(file);
-  smx_host_t *hosts = SIMIX_host_get_table();
-  int i;
-  for (i=0;i<SIMIX_host_get_number();i++) {
-    DEBUG1("We have an host %s", SIMIX_host_get_name(hosts[i]));
+    lua_pop(L, 1);              /* pop returned value */
   }
 
-  return 0;
-}
+  XBT_DEBUG("Execution of Lua code %s is over", (argv ? argv[0] : "(null)"));
 
-static int debug(lua_State *L) {
-  const char *str = luaL_checkstring(L,1);
-  DEBUG1("%s",str);
-  return 0;
-}
-static int info(lua_State *L) {
-  const char *str = luaL_checkstring(L,1);
-  INFO1("%s",str);
-  return 0;
-}
-static int run(lua_State *L) {
-  MSG_main();
-  return 0;
-}
-static int clean(lua_State *L) {
-  MSG_clean();
-  return 0;
+  return res;
 }
 
-/*
- * Bypass XML Pareser
+/**
+ * \brief Returns a string corresponding to an MSG error code.
+ * \param err an MSG error code
+ * \return a string describing this error
  */
-static int register_platform(lua_State *L)
-{
-       /* Tell Simgrid we dont wanna use its parser*/
-       surf_parse = surf_parse_bypass_platform;
-       MSG_create_environment(NULL);
-       return 0;
-}
-
-static int register_application(lua_State *L)
-{
-        MSG_function_register_default(run_lua_code);
-        surf_parse = surf_parse_bypass_application;
-        MSG_launch_application(NULL);
-        return 0;
-}
-
-static const luaL_Reg simgrid_funcs[] = {
-    { "create_environment", create_environment},
-    { "launch_application", launch_application},
-    { "debug", debug},
-    { "info", info},
-    { "run", run},
-    { "clean", clean},
-    /* short names */
-    { "platform", create_environment},
-    { "application", launch_application},
-    /* methods to bypass XML parser*/
-    { "register_platform",register_platform},
-    { "register_application",register_application},
-    { NULL, NULL }
-};
-
-/* ********************************************************************************* */
-/*                       module management functions                                 */
-/* ********************************************************************************* */
-
-extern const char*xbt_ctx_factory_to_use; /*Hack: let msg load directly the right factory */
-
-#define LUA_MAX_ARGS_COUNT 10 /* maximum amount of arguments we can get from lua on command line */
-
-int luaopen_simgrid(lua_State* L); // Fuck gcc: we don't need that prototype
-int luaopen_simgrid(lua_State* L) {
-  //xbt_ctx_factory_to_use = "lua";
-
-  char **argv=malloc(sizeof(char*)*LUA_MAX_ARGS_COUNT);
-  int argc=1;
-  argv[0] = (char*)"/usr/bin/lua"; /* Lie on the argv[0] so that the stack dumping facilities find the right binary. FIXME: what if lua is not in that location? */
-  /* Get the command line arguments from the lua interpreter */
-  lua_getglobal(L,"arg");
-  xbt_assert1(lua_istable(L,-1),"arg parameter is not a table but a %s",lua_typename(L,-1));
-  int done=0;
-  while (!done) {
-    argc++;
-    lua_pushinteger(L,argc-2);
-    lua_gettable(L,-2);
-    if (lua_isnil(L,-1)) {
-      done = 1;
-    } else {
-      xbt_assert1(lua_isstring(L,-1),"argv[%d] got from lua is no string",argc-1);
-      xbt_assert2(argc<LUA_MAX_ARGS_COUNT,
-           "Too many arguments, please increase LUA_MAX_ARGS_COUNT in %s before recompiling SimGrid if you insist on having more than %d args on command line",
-           __FILE__,LUA_MAX_ARGS_COUNT-1);
-      argv[argc-1] = (char*)luaL_checkstring(L,-1);
-      lua_pop(L,1);
-      DEBUG1("Got command line argument %s from lua",argv[argc-1]);
-    }
-  }
-  argv[argc--]=NULL;
-
-  /* Initialize the MSG core */
-  MSG_global_init(&argc,argv);
-  DEBUG1("Still %d arguments on command line",argc); // FIXME: update the lua's arg table to reflect the changes from SimGrid
+const char* sglua_get_msg_error(MSG_error_t err) {
 
-  /* register the core C functions to lua */
-  luaL_register(L, "simgrid", simgrid_funcs);
-  /* register the task methods to lua */
-  luaL_openlib(L,TASK_MODULE_NAME,Task_methods,0); //create methods table,add it to the globals
-  luaL_newmetatable(L,TASK_MODULE_NAME); //create metatable for Task,add it to the Lua registry
-  luaL_openlib(L,0,Task_meta,0);// fill metatable
-  lua_pushliteral(L,"__index");
-  lua_pushvalue(L,-3);  //dup methods table
-  lua_rawset(L,-3); //matatable.__index = methods
-  lua_pushliteral(L,"__metatable");
-  lua_pushvalue(L,-3);  //dup methods table
-  lua_rawset(L,-3); //hide metatable:metatable.__metatable = methods
-  lua_pop(L,1);   //drop metatable
-
-  /* register the hosts methods to lua*/
-  luaL_openlib(L,HOST_MODULE_NAME,Host_methods,0);
-  luaL_newmetatable(L,HOST_MODULE_NAME);
-  luaL_openlib(L,0,Host_meta,0);
-  lua_pushliteral(L,"__index");
-  lua_pushvalue(L,-3);
-  lua_rawset(L,-3);
-  lua_pushliteral(L,"__metatable");
-  lua_pushvalue(L,-3);
-  lua_rawset(L,-3);
-  lua_pop(L,1);
-
-  /* register the links methods to lua*/
-  luaL_openlib(L,LINK_MODULE_NAME,Link_methods,0);
-  luaL_newmetatable(L,LINK_MODULE_NAME);
-  lua_pop(L,1);
-
-  /*register the routes methods to lua*/
-  luaL_openlib(L,ROUTE_MODULE_NAME,Route_methods,0);
-  luaL_newmetatable(L,LINK_MODULE_NAME);
-  lua_pop(L,1);
+  static const char* msg_errors[] = {
+      NULL,
+      "timeout",
+      "transfer failure",
+      "host failure",
+      "task canceled"
+  };
 
-  /* Keep the context mechanism informed of our lua world today */
-  simgrid_lua_state = L;
-  return 1;
+  return msg_errors[err];
 }