+++ /dev/null
-/* Copyright (c) 2010-2014. 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. */
-
-/* SimGrid Lua state management */
-
-#include "lua_state_cloner.h"
-#include "lua_utils.h"
-#include "xbt.h"
-#include "xbt/log.h"
-#include <lauxlib.h>
-#include <lualib.h>
-
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua_state_cloner, bindings, "Lua state management");
-
-static void sglua_add_maestro_table(lua_State* L, int index, void* maestro_table_ptr);
-static void sglua_remove_maestro_table(lua_State* L, int index, void* maestro_table_ptr);
-static void* sglua_get_maestro_table_ptr(lua_State* L, int index);
-static void sglua_get_table_by_ptr(lua_State* L, void* table_ptr);
-static int l_get_from_maestro(lua_State* L);
-
-static void sglua_copy_nil(lua_State* src, lua_State* dst);
-static void sglua_copy_number(lua_State* src, lua_State* dst);
-static void sglua_copy_boolean(lua_State* src, lua_State* dst);
-static void sglua_copy_string(lua_State* src, lua_State* dst);
-static void sglua_copy_table(lua_State* src, lua_State* dst);
-static void sglua_copy_function(lua_State* src, lua_State* dst);
-static void sglua_copy_lightuserdata(lua_State* src, lua_State* dst);
-static void sglua_copy_userdata(lua_State* src, lua_State* dst);
-static void sglua_copy_thread(lua_State* src, lua_State* dst);
-
-/**
- * @brief Adds a reference to a maestro table to the list of known maestro
- * tables of a state.
- *
- * TODO identify maestro's tables with my own IDs instead of pointers
- * to Lua internals
- *
- * @param L a state (can be maestro itself)
- * @param index index of the copy of the maestro table in the stack of L
- * @param maestro_table_ptr pointer to the original table in maestro's world
- */
-static void sglua_add_maestro_table(lua_State* L, int index, void* maestro_table_ptr) {
-
- /* we will set both [ptr] -> table and [table] -> ptr */
-
- /* ... */
- lua_pushvalue(L, index);
- /* ... table */
- lua_pushstring(L, "simgrid.maestro_tables");
- /* ... table "simgrid.maestro_tables" */
- lua_rawget(L, LUA_REGISTRYINDEX);
- /* ... table maestrotbs */
- lua_pushvalue(L, -2);
- /* ... table maestrotbs table */
- lua_pushlightuserdata(L, maestro_table_ptr);
- /* ... table maestrotbs table tableptr */
- lua_pushvalue(L, -1);
- /* ... table maestrotbs table tableptr tableptr */
- lua_pushvalue(L, -3);
- /* ... table maestrotbs table tableptr tableptr table */
- lua_settable(L, -5);
- /* ... table maestrotbs table tableptr */
- lua_settable(L, -3);
- /* ... table maestrotbs */
- lua_pop(L, 2);
- /* ... */
-}
-
-/**
- * @brief Removes a reference to a maestro table to the list of known maestro
- * tables of a state.
- *
- * @param L a state (can be maestro itself)
- * @param index index of the copy of the maestro table in the stack of L
- * @param maestro_table_ptr pointer to the original table in maestro's world
- */
-static void sglua_remove_maestro_table(lua_State* L, int index, void* maestro_table_ptr) {
-
- /* we will unset both [ptr] -> table and [table] -> ptr */
-
- /* ... */
- lua_pushvalue(L, index);
- /* ... table */
- lua_pushstring(L, "simgrid.maestro_tables");
- /* ... table "simgrid.maestro_tables" */
- lua_rawget(L, LUA_REGISTRYINDEX);
- /* ... table maestrotbs */
- lua_pushvalue(L, -2);
- /* ... table maestrotbs table */
- lua_pushnil(L);
- /* ... table maestrotbs table nil */
- lua_pushlightuserdata(L, maestro_table_ptr);
- /* ... table maestrotbs table nil tableptr */
- lua_pushnil(L);
- /* ... table maestrotbs table nil tableptr nil*/
- lua_settable(L, -5);
- /* ... table maestrotbs table nil */
- lua_settable(L, -3);
- /* ... table maestrotbs */
- lua_pop(L, 2);
- /* ... */
-}
-
-/**
- * @brief For a table in the stack of L, returns a pointer that identifies the
- * same table in in maestro's world.
- * @param L a Lua state
- * @param index index of a table in the stack of L
- * @return a pointer to maestro's copy of this table, or NULL if this table
- * did not come from maestro
- */
-static void* sglua_get_maestro_table_ptr(lua_State* L, int index) {
-
- void* maestro_table_ptr = NULL;
- /* ... */
- lua_pushvalue(L, index);
- /* ... table */
- lua_pushstring(L, "simgrid.maestro_tables");
- /* ... table "simgrid.maestro_tables" */
- lua_rawget(L, LUA_REGISTRYINDEX);
- /* ... table maestrotbs */
- lua_pushvalue(L, -2);
- /* ... table maestrotbs table */
- lua_gettable(L, -2);
- /* ... table maestrotbs tableptr/nil */
- if (!lua_isnil(L, -1)) {
- /* ... table maestrotbs tableptr */
- maestro_table_ptr = (void*) lua_topointer(L, -1);
- }
-
- lua_pop(L, 3);
- /* ... */
- return maestro_table_ptr;
-}
-
-/**
- * @brief Pushes a table knowing a pointer to maestro's copy of this table.
- *
- * Pushes nil if L does not know this table in maestro.
- *
- * @param L a Lua state
- * @param maestro_table_ptr pointer that identifies a table in maestro's world
- */
-static void sglua_get_table_by_ptr(lua_State* L, void* maestro_table_ptr) {
-
- /* ... */
- lua_pushstring(L, "simgrid.maestro_tables");
- /* ... "simgrid.maestro_tables" */
- lua_rawget(L, LUA_REGISTRYINDEX);
- /* ... maestrotbs */
- lua_pushlightuserdata(L, maestro_table_ptr);
- /* ... maestrotbs tableptr */
- lua_gettable(L, -2);
- /* ... maestrotbs table/nil */
- lua_remove(L, -2);
- /* ... table/nil */
-}
-
-/**
- * @brief Pops a value from the stack of a source state and pushes it on the
- * stack of another state.
- * If the value is a table, its content is copied recursively.
- *
- * This function is similar to lua_xmove() but it allows to move a value
- * between two different global states.
- *
- * @param src the source state (not necessarily maestro)
- * @param dst the destination state
- */
-void sglua_move_value(lua_State* src, lua_State* dst) {
-
- sglua_copy_value(src, dst);
- lua_pop(src, 1);
-}
-
-/**
- * @brief Pushes onto the stack a copy of the value on top another stack.
- * If the value is a table, its content is copied recursively.
- *
- * This function allows to move a value between two different global states.
- *
- * @param src the source state (not necessarily maestro)
- * @param dst the destination state
- */
-void sglua_copy_value(lua_State* src, lua_State* dst) {
-
- luaL_checkany(src, -1); /* check the value to copy */
-
- int indent = (lua_gettop(dst) - 1) * 6;
- XBT_DEBUG("%sCopying data %s", sglua_get_spaces(indent), sglua_tostring(src, -1));
-
- sglua_stack_dump("src before copying a value (should be ... value): ", src);
- sglua_stack_dump("dst before copying a value (should be ...): ", dst);
-
- switch (lua_type(src, -1)) {
-
- case LUA_TNIL:
- sglua_copy_nil(src, dst);
- break;
-
- case LUA_TNUMBER:
- sglua_copy_number(src, dst);
- break;
-
- case LUA_TBOOLEAN:
- sglua_copy_boolean(src, dst);
- break;
-
- case LUA_TSTRING:
- sglua_copy_string(src, dst);
- break;
-
- case LUA_TFUNCTION:
- sglua_copy_function(src, dst);
- break;
-
- case LUA_TTABLE:
- sglua_copy_table(src, dst);
- break;
-
- case LUA_TLIGHTUSERDATA:
- sglua_copy_lightuserdata(src, dst);
- break;
-
- case LUA_TUSERDATA:
- sglua_copy_userdata(src, dst);
- break;
-
- case LUA_TTHREAD:
- sglua_copy_thread(src, dst);
- break;
-
- case LUA_TNONE:
- XBT_ERROR("This index is acceptable but non-valid");
- break;
- }
-
- XBT_DEBUG("%sData copied", sglua_get_spaces(indent));
-
- sglua_stack_dump("src after copying a value (should be ... value): ", src);
- sglua_stack_dump("dst after copying a value (should be ... value): ", dst);
-}
-
-/**
- * @brief Copies the nil value on the top of src to the top of dst.
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_nil(lua_State* src, lua_State* dst) {
- lua_pushnil(dst);
-}
-
-/**
- * @brief Copies the number value on the top of src to the top of dst.
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_number(lua_State* src, lua_State* dst) {
- lua_Number n = lua_tonumber(src, -1);
- if ( ((lua_Integer) n) == n) {
- lua_pushinteger(dst, lua_tointeger(src, -1));
- }
- else
- lua_pushnumber(dst, lua_tonumber(src, -1));
-}
-
-/**
- * @brief Copies the boolean value on the top of src to the top of dst.
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_boolean(lua_State* src, lua_State* dst) {
- lua_pushboolean(dst, lua_toboolean(src, -1));
-}
-
-/**
- * @brief Copies the string value on the top of src to the top of dst.
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_string(lua_State* src, lua_State* dst) {
-
- /* no worries about memory: lua_pushstring makes a copy */
- lua_pushstring(dst, lua_tostring(src, -1));
-}
-
-/**
- * @brief Copies the table value on top of src to the top of dst.
- *
- * A deep copy of the table is made. If the table has a metatable, the
- * metatable is also copied.
- * If the table comes from maestro and is already known by the destination
- * state, it is not copied again.
- *
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_table(lua_State* src, lua_State* dst) {
-
- /* src: ... table
- dst: ... */
- int indent = lua_gettop(dst) * 6 + 2;
-
- /* get from maestro the pointer that identifies this table */
- void* table_ptr = sglua_get_maestro_table_ptr(src, -1);
- int known_by_maestro = (table_ptr != NULL);
-
- if (!known_by_maestro) {
- /* the table didn't come from maestro: nevermind, use the pointer of src */
- table_ptr = (void*) lua_topointer(src, -1);
- XBT_DEBUG("%sMaestro does not know this table",
- sglua_get_spaces(indent));
- }
-
- if (sglua_is_maestro(src)) {
- /* register the table in maestro itself */
- XBT_DEBUG("%sKeeping track of this table in maestro itself",
- sglua_get_spaces(indent));
- sglua_add_maestro_table(src, -1, table_ptr);
- known_by_maestro = 1;
- xbt_assert(sglua_get_maestro_table_ptr(src, -1) == table_ptr);
- }
-
- /* to avoid infinite recursion, see if this table is already known by dst */
- sglua_get_table_by_ptr(dst, table_ptr);
- /* dst: ... table/nil */
- if (!lua_isnil(dst, -1)) {
- XBT_DEBUG("%sNothing to do: table already known (%p)",
- sglua_get_spaces(indent), table_ptr);
- /* dst: ... table */
- }
- else {
- XBT_DEBUG("%sFirst visit of this table (%p)", sglua_get_spaces(indent),
- table_ptr);
- /* dst: ... nil */
- lua_pop(dst, 1);
- /* dst: ... */
-
- /* first visit: create the new table in dst */
- lua_newtable(dst);
- /* dst: ... table */
-
- /* mark the table as known right now to avoid infinite recursion */
- sglua_add_maestro_table(dst, -1, table_ptr);
- /* we may have added a table with a non-maestro pointer, but if it was the
- * case, we will remove it later */
- XBT_DEBUG("%sTable marked as known", sglua_get_spaces(indent));
- xbt_assert(sglua_get_maestro_table_ptr(dst, -1) == table_ptr);
-
- sglua_stack_dump("dst after marking the table as known (should be ... table): ", dst);
-
- /* copy the metatable if any */
- int has_meta_table = lua_getmetatable(src, -1);
- /* src: ... table mt? */
- if (has_meta_table) {
- XBT_DEBUG("%sCopying the metatable", sglua_get_spaces(indent));
- /* src: ... table mt */
- sglua_copy_table(src, dst);
- /* dst: ... table mt */
- lua_pop(src, 1);
- /* src: ... table */
- lua_setmetatable(dst, -2);
- /* dst: ... table */
- }
- else {
- /* src: ... table */
- XBT_DEBUG("%sNo metatable", sglua_get_spaces(indent));
- }
-
- sglua_stack_dump("src before traversing the table (should be ... table): ", src);
- sglua_stack_dump("dst before traversing the table (should be ... table): ", dst);
-
- /* traverse the table of src and copy each element */
- lua_pushnil(src);
- /* src: ... table nil */
- while (lua_next(src, -2) != 0) {
- /* src: ... table key value */
-
- XBT_DEBUG("%sCopying table element %s", sglua_get_spaces(indent),
- sglua_keyvalue_tostring(src, -2, -1));
-
- sglua_stack_dump("src before copying table element (should be ... table key value): ", src);
- sglua_stack_dump("dst before copying table element (should be ... table): ", dst);
-
- /* copy the key */
- lua_pushvalue(src, -2);
- /* src: ... table key value key */
- indent += 2;
- XBT_DEBUG("%sCopying the key part of the table element",
- sglua_get_spaces(indent));
- sglua_move_value(src, dst);
- /* src: ... table key value
- dst: ... table key */
- XBT_DEBUG("%sCopied the key part of the table element",
- sglua_get_spaces(indent));
-
- /* copy the value */
- XBT_DEBUG("%sCopying the value part of the table element",
- sglua_get_spaces(indent));
- sglua_move_value(src, dst);
- /* src: ... table key
- dst: ... table key value */
- XBT_DEBUG("%sCopied the value part of the table element",
- sglua_get_spaces(indent));
- indent -= 2;
-
- /* set the table element */
- lua_settable(dst, -3);
- /* dst: ... table */
-
- /* the key stays on top of src for next iteration */
- sglua_stack_dump("src before next iteration (should be ... table key): ", src);
- sglua_stack_dump("dst before next iteration (should be ... table): ", dst);
-
- XBT_DEBUG("%sTable element copied", sglua_get_spaces(indent));
- }
- XBT_DEBUG("%sFinished traversing the table", sglua_get_spaces(indent));
- }
-
- if (!known_by_maestro) {
- /* actually,it was not a maestro table: forget the pointer */
- sglua_remove_maestro_table(dst, -1, table_ptr);
- }
-}
-
-/**
- * @brief Copies the function on the top of src to the top of dst.
- *
- * It can be a Lua function or a C function.
- *
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_function(lua_State* src, lua_State* dst) {
-
- if (lua_iscfunction(src, -1)) {
- /* it's a C function */
-
- XBT_DEBUG("It's a C function");
- sglua_stack_dump("src before copying upvalues: ", src);
-
- /* get the function pointer */
- int function_index = lua_gettop(src);
- lua_CFunction f = lua_tocfunction(src, function_index);
-
- /* copy the upvalues */
- int i = 0;
- const char* upvalue_name = NULL;
- do {
- i++;
- upvalue_name = lua_getupvalue(src, function_index, i);
-
- if (upvalue_name != NULL) {
- XBT_DEBUG("Upvalue %s", upvalue_name);
- sglua_move_value(src, dst);
- }
- } while (upvalue_name != NULL);
-
- sglua_stack_dump("src before copying pointer: ", src);
-
- /* set the function */
- lua_pushcclosure(dst, f, i - 1);
- XBT_DEBUG("Function pointer copied");
- }
- else {
- /* it's a Lua function: dump it from src */
-
- s_sglua_buffer_t buffer;
- buffer.capacity = 128; /* an empty function uses 77 bytes */
- buffer.size = 0;
- buffer.data = xbt_new(char, buffer.capacity);
-
- /* copy the binary chunk from src into a buffer
- * c.heinrich: Added parameter TRUE for Lua 5.3 - this strips all debug
- * information from the function.
- */
- // Was before merge: XBT_GNUC_UNUSED and was replaced with XBT_ATTRIB_UNUSED
- XBT_ATTRIB_UNUSED int error = lua_dump(src, sglua_memory_writer, &buffer, TRUE);
- xbt_assert(!error, "Failed to dump the function from the source state: error %d",
- error);
- XBT_DEBUG("Fonction dumped: %zu bytes", buffer.size);
-
- /*
- fwrite(buffer.data, buffer.size, buffer.size, stderr);
- fprintf(stderr, "\n");
- */
-
- /* load the chunk into dst */
- error = luaL_loadbuffer(dst, buffer.data, buffer.size, "(dumped function)");
- xbt_assert(!error, "Failed to load the function into the destination state: %s",
- lua_tostring(dst, -1));
- }
-}
-
-/**
- * @brief Copies the light userdata on the top of src to the top of dst.
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_lightuserdata(lua_State* src, lua_State* dst) {
- lua_pushlightuserdata(dst, lua_touserdata(src, -1));
-}
-
-/**
- * @brief Copies the full userdata on the top of src to the top of dst.
- *
- * If the userdata has a metatable, the metatable is also copied.
- *
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_userdata(lua_State* src, lua_State* dst) {
-
- int indent = lua_gettop(dst) * 6 + 2;
-
- /* copy the data */
- /* src: ... udata
- dst: ... */
- size_t size = lua_rawlen(src, -1);
- void* src_block = lua_touserdata(src, -1);
- void* dst_block = lua_newuserdata(dst, size);
- /* dst: ... udata */
- memcpy(dst_block, src_block, size);
-
- /* copy the metatable if any */
- int has_meta_table = lua_getmetatable(src, -1);
- /* src: ... udata mt? */
- if (has_meta_table) {
- XBT_DEBUG("%sCopying metatable of userdata (%p)",
- sglua_get_spaces(indent), lua_topointer(src, -1));
- /* src: ... udata mt */
- sglua_copy_table(src, dst);
- /* src: ... udata mt
- dst: ... udata mt */
- lua_pop(src, 1);
- /* src: ... udata */
- lua_setmetatable(dst, -2);
- /* dst: ... udata */
-
- XBT_DEBUG("%sMetatable of userdata copied", sglua_get_spaces(indent));
- }
- else {
- XBT_DEBUG("%sNo metatable for this userdata",
- sglua_get_spaces(indent));
- /* src: ... udata */
- }
-}
-
-/**
- * @brief This operation is not supported (yet?) so it just pushes nil.
- *
- * @param src source state
- * @param dst destination state
- */
-static void sglua_copy_thread(lua_State* src, lua_State* dst) {
-
- XBT_WARN("Copying a thread from another state is not implemented (yet?).");
- lua_pushnil(dst);
-}
-
-/**
- * @brief Copies a global value or a registry value from the maestro state.
- *
- * The state L must have been created by sglua_clone_maestro_state().
- * This function is meant to be an __index metamethod.
- * Consequently, it assumes that the stack has two elements:
- * a table (either the environment or the registry of L) and the string key of
- * a value that does not exist yet in this table. It copies the corresponding
- * value from maestro and pushes it on the stack of L.
- * If the value does not exist in maestro state either, nil is pushed.
- *
- * TODO: make this function thread safe. If the simulation runs in parallel,
- * several simulated processes may trigger this __index metamethod at the same
- * time and get globals from maestro.
- *
- * @param L the current state
- * @return number of return values pushed (always 1)
- */
-static int l_get_from_maestro(lua_State *L) {
-
- /* check the arguments */
- luaL_checktype(L, 1, LUA_TTABLE);
- const char* key = luaL_checkstring(L, 2);
- /* L: table key */
- XBT_DEBUG("__index of '%s' begins", key);
-
- /* get the father */
- lua_State* maestro = sglua_get_maestro(); /* maestro: */
-
- /* want a global or a registry value?
- get the value from maestro */
- if (lua_compare(L, 1, LUA_REGISTRYINDEX, LUA_OPEQ)) {
- /* case: registry */
- lua_getfield(maestro, LUA_REGISTRYINDEX, key); /* maestro: ... value */
- XBT_DEBUG("Will get the value from the registry of maestro");
- }
- else { /* case: global */
- lua_getglobal(maestro, key); /* maestro: ... value */
- XBT_DEBUG("Will get the value from the globals of maestro");
- }
-
- /* L: table key */
-
-
- /* push the value onto the stack of L */
- sglua_move_value(maestro, L);
- /* maestro: ...
- L: table key value */
-
- /* prepare the return value of __index */
- lua_pushvalue(L, -1);
- /* L: table key value value */
- lua_insert(L, 1);
- /* L: value table key value */
-
- /* save the copied value in the table for subsequent accesses */
- lua_settable(L, -3);
- /* L: value table */
- lua_settop(L, 1);
- /* L: value */
-
- XBT_DEBUG("__index of '%s' returns %s", key, sglua_tostring(L, -1));
-
- return 1;
-}
-
-/**
- * @brief Creates a new Lua state and get its environment from the maestro
- * state.
- *
- * The state created is independent from maestro and has its own copies of
- * global and registry values.
- * However, the global and registry values are not copied right now from
- * the original state; they are copied only the first time they are accessed.
- * This behavior saves time and memory, and is okay for Simgrid's needs.
- *
- * TODO: if the simulation runs in parallel, copy everything right now?
- *
- * @return the state created
- */
-lua_State* sglua_clone_maestro(void) {
-
- /* create the new state */
- lua_State *L = luaL_newstate();
-
- /* set its environment and its registry:
- * - create a table newenv
- * - create a metatable mt
- * - set mt.__index = a function that copies the global from the father state
- * - set mt as the metatable of the registry
- * - set mt as the metatable of newenv
- * - set newenv as the environment of the new state
- */
- lua_pushthread(L); /* thread */
- lua_newtable(L); /* thread newenv */
- lua_newtable(L); /* thread newenv mt */
- lua_pushvalue(L, LUA_REGISTRYINDEX); /* thread newenv mt reg */
- lua_pushcfunction(L, l_get_from_maestro); /* thread newenv mt reg f */
- lua_setfield(L, -3, "__index"); /* thread newenv mt reg */
- lua_pushvalue(L, -2); /* thread newenv mt reg mt */
- lua_setmetatable(L, -2); /* thread newenv mt reg */
- lua_pop(L, 1); /* thread newenv mt */
- lua_setmetatable(L, -2); /* thread newenv */
- lua_pushvalue(L, LUA_REGISTRYINDEX); /* thread newenv reg */
- lua_insert(L, -2); /* thread reg newenv */
- lua_seti(L, -2, LUA_RIDX_GLOBALS); /* thread reg */
- lua_pop(L, 2); /* -- */
-
- /* create the table of known tables from maestro */
- lua_pushstring(L, "simgrid.maestro_tables");
- /* "simgrid.maestro_tables" */
- lua_newtable(L); /* "simgrid.maestro_tables" maestrotbs */
- lua_rawset(L, LUA_REGISTRYINDEX);
- /* -- */
-
- /* opening the standard libs is not necessary as they are
- * inherited like any global values */
- /* luaL_openlibs(L); */
-
- XBT_DEBUG("New state created");
-
- return L;
-}
