-/* Copyright (c) 2010. The SimGrid Team.
+/* Copyright (c) 2010-2014. The SimGrid Team.
* All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
#include <lauxlib.h>
#include <lualib.h>
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua_state_cloner, lua, "Lua state management");
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua_state_cloner, bindings, "Lua state management");
-static lua_State* sglua_get_father(lua_State* L);
-static int l_get_from_father(lua_State* L);
+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_move_value_impl(lua_State* src, lua_State* dst, const char* name);
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_thread(lua_State* src, lua_State* dst);
/**
- * @brief Returns the father of a state, i.e. the state that created it.
- * @param L a Lua state
- * @return its father, or NULL if the state was not created by sglua_clone_state()
+ * @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 lua_State* sglua_get_father(lua_State* L) {
+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_pushstring(L, "simgrid.father");
- /* ... "simgrid.father" */
+ lua_pushvalue(L, index);
+ /* ... table */
+ lua_pushstring(L, "simgrid.maestro_tables");
+ /* ... table "simgrid.maestro_tables" */
lua_rawget(L, LUA_REGISTRYINDEX);
- /* ... father */
- lua_State* father = lua_touserdata(L, -1);
- lua_pop(L, 1);
+ /* ... 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);
/* ... */
- return father;
}
/**
- * @brief Pops a value from a state and pushes it onto the stack of another
- * state.
+ * @brief Removes a reference to a maestro table to the list of known maestro
+ * tables of a state.
*
- * @param src the source state
- * @param dst the destination 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
*/
-void sglua_move_value(lua_State* src, lua_State* dst) {
+static void sglua_remove_maestro_table(lua_State* L, int index, void* maestro_table_ptr) {
- if (src != dst) {
+ /* we will unset both [ptr] -> table and [table] -> ptr */
- /* get the list of visited tables from father at index 1 of dst */
- /* src: ... value
- dst: ... */
- lua_getfield(dst, LUA_REGISTRYINDEX, "simgrid.father_visited_tables");
- /* dst: ... visited */
- lua_insert(dst, 1);
- /* dst: visited ... */
-
- sglua_move_value_impl(src, dst, sglua_tostring(src, -1));
- /* src: ...
- dst: visited ... value */
- lua_remove(dst, 1);
- /* dst: ... value */
- sglua_stack_dump("src after xmove: ", src);
- sglua_stack_dump("dst after xmove: ", dst);
+ /* ... */
+ 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.
*
- * If the value is a table, its content is copied recursively. To avoid cycles,
- * a table of previously visited tables must be present at index 1 of dst.
- * Its keys are pointers to visited tables in src and its values are the tables
- * already built.
+ * This function is similar to lua_xmove() but it allows to move a value
+ * between two different global states.
*
- * TODO: add support of closures
+ * @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.
*
- * @param src the source state
- * @param dst the destination state, with a list of visited tables at index 1
- * @param name a name describing the value (for debugging purposes)
+ * 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
*/
-static void sglua_move_value_impl(lua_State* src, lua_State *dst, const char* name) {
+void sglua_copy_value(lua_State* src, lua_State* dst) {
luaL_checkany(src, -1); /* check the value to copy */
- luaL_checktype(dst, 1, LUA_TTABLE); /* check the presence of a table of
- previously visited tables */
int indent = (lua_gettop(dst) - 1) * 6;
- XBT_DEBUG("%sCopying data %s", sglua_get_spaces(indent), name);
+ 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 visited ...): ", dst);
+ sglua_stack_dump("dst before copying a value (should be ...): ", dst);
switch (lua_type(src, -1)) {
case LUA_TTHREAD:
sglua_copy_thread(src, dst);
break;
- }
- /* the value has been copied to dst: remove it from src */
- lua_pop(src, 1);
+ case LUA_TNONE:
+ XBT_ERROR("This index is acceptable but non-valid");
+ break;
+ }
- indent -= 2;
XBT_DEBUG("%sData copied", sglua_get_spaces(indent));
- sglua_stack_dump("src after copying a value (should be ...): ", src);
- sglua_stack_dump("dst after copying a value (should be visited ... value): ", dst);
+ sglua_stack_dump("src after copying a value (should be ... value): ", src);
+ sglua_stack_dump("dst after copying a value (should be ... value): ", dst);
}
/**
* @param dst destination state
*/
static void sglua_copy_number(lua_State* src, lua_State* dst) {
- lua_pushnumber(dst, lua_tonumber(src, -1));
+ 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));
}
/**
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 */
}
/**
- * @brief Copies the table value on the top of src to the top of dst.
+ * @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 is already known by the destination state, nothing is
- * done.
+ * 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) {
- int indent = (lua_gettop(dst) - 1) * 6 + 2;
-
- /* first register the table in the source state itself */
- lua_getfield(src, LUA_REGISTRYINDEX, "simgrid.visited_tables");
- /* src: ... table visited */
- lua_pushvalue(src, -2);
- /* src: ... table visited table */
- lua_pushlightuserdata(src, (void*) lua_topointer(src, -1));
- /* src: ... table visited table psrctable */
- lua_pushvalue(src, -1);
- /* src: ... table visited table psrctable psrctable */
- lua_pushvalue(src, -3);
- /* src: ... table visited table psrctable psrctable table */
- lua_settable(src, -5);
- /* src: ... table visited table psrctable */
- lua_settable(src, -3);
- /* src: ... table visited */
- lua_pop(src, 1);
- /* src: ... table */
-
- /* see if this table was already known by dst */
- lua_pushlightuserdata(dst, (void*) lua_topointer(src, -1));
- /* dst: visited ... psrctable */
- lua_gettable(dst, 1);
- /* dst: visited ... table/nil */
- if (lua_istable(dst, -1)) {
- XBT_DEBUG("%sNothing to do: table already visited (%p)",
- sglua_get_spaces(indent), lua_topointer(src, -1));
- /* dst: visited ... table */
+ /* 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),
- lua_topointer(src, -1));
- /* dst: visited ... nil */
+ table_ptr);
+ /* dst: ... nil */
lua_pop(dst, 1);
- /* dst: visited ... */
+ /* dst: ... */
/* first visit: create the new table in dst */
lua_newtable(dst);
- /* dst: visited ... table */
-
- /* mark the table as visited right now to avoid infinite recursion */
- lua_pushlightuserdata(dst, (void*) lua_topointer(src, -1));
- /* dst: visited ... table psrctable */
- lua_pushvalue(dst, -2);
- /* dst: visited ... table psrctable table */
- lua_pushvalue(dst, -1);
- /* dst: visited ... table psrctable table table */
- lua_pushvalue(dst, -3);
- /* dst: visited ... table psrctable table table psrctable */
- lua_settable(dst, 1);
- /* dst: visited ... table psrctable table */
- lua_settable(dst, 1);
- /* dst: visited ... table */
- XBT_DEBUG("%sTable marked as visited", sglua_get_spaces(indent));
-
- sglua_stack_dump("dst after marking the table as visited (should be visited ... table): ", 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? */
+ /* src: ... table mt? */
if (has_meta_table) {
- XBT_DEBUG("%sCopying metatable", sglua_get_spaces(indent));
- /* src: ... table mt */
+ XBT_DEBUG("%sCopying the metatable", sglua_get_spaces(indent));
+ /* src: ... table mt */
sglua_copy_table(src, dst);
- /* dst: visited ... table mt */
+ /* dst: ... table mt */
lua_pop(src, 1);
- /* src: ... table */
+ /* src: ... table */
lua_setmetatable(dst, -2);
- /* dst: visited ... table */
+ /* 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 visited ... table): ", dst);
+ 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 */
+ /* src: ... table nil */
while (lua_next(src, -2) != 0) {
- /* src: ... table key value */
+ /* 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 visited ... table): ", dst);
+ sglua_stack_dump("dst before copying table element (should be ... table): ", dst);
/* copy the key */
lua_pushvalue(src, -2);
- /* src: ... table key value key */
+ /* src: ... table key value key */
indent += 2;
XBT_DEBUG("%sCopying the key part of the table element",
sglua_get_spaces(indent));
- sglua_move_value_impl(src, dst, sglua_tostring(src, -1));
- /* src: ... table key value
- dst: visited ... table key */
+ 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_impl(src, dst, sglua_tostring(src, -1));
- /* src: ... table key
- dst: visited ... table key value */
+ 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: visited ... table */
+ /* 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 visited ... table): ", dst);
+ 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.
- * Copying upvalues is not implemented yet (TODO).
*
* @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: just copy the pointer */
- lua_CFunction f = lua_tocfunction(src, -1);
- lua_pushcfunction(dst, f);
+ /* 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 = 64;
+ 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 */
- int error = lua_dump(src, sglua_memory_writer, &buffer);
+ /* 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)");
*/
static void sglua_copy_userdata(lua_State* src, lua_State* dst) {
- int indent = (lua_gettop(dst) - 1) * 6 + 2;
+ int indent = lua_gettop(dst) * 6 + 2;
/* copy the data */
/* src: ... udata
- dst: visited ... */
- size_t size = lua_objlen(src, -1);
+ dst: ... */
+ size_t size = lua_rawlen(src, -1);
void* src_block = lua_touserdata(src, -1);
void* dst_block = lua_newuserdata(dst, size);
- /* dst: visited ... udata */
+ /* dst: ... udata */
memcpy(dst_block, src_block, size);
/* copy the metatable if any */
XBT_DEBUG("%sCopying metatable of userdata (%p)",
sglua_get_spaces(indent), lua_topointer(src, -1));
/* src: ... udata mt */
- lua_State* father = sglua_get_father(dst);
-
- if (father != NULL && src != father && sglua_get_father(src) == father) {
- XBT_DEBUG("%sGet the metatable from my father",
- sglua_get_spaces(indent));
- /* I don't want the metatable of src, I want the father's copy of the
- same metatable */
-
- /* get from src the pointer to the father's copy of this metatable */
- lua_pushstring(src, "simgrid.father_visited_tables");
- /* src: ... udata mt "simgrid.visited_tables" */
- lua_rawget(src, LUA_REGISTRYINDEX);
- /* src: ... udata mt visited */
- lua_pushvalue(src, -2);
- /* src: ... udata mt visited mt */
- lua_gettable(src, -2);
- /* src: ... udata mt visited pfathermt */
-
- /* copy the metatable from the father world into dst */
- lua_pushstring(father, "simgrid.visited_tables");
- /* father: ... "simgrid.visited_tables" */
- lua_rawget(father, LUA_REGISTRYINDEX);
- /* father: ... visited */
- lua_pushlightuserdata(father, (void*) lua_topointer(src, -1));
- /* father: ... visited pfathermt */
- lua_gettable(father, -2);
- /* father: ... visited mt */
- sglua_move_value_impl(father, dst, "(father metatable)");
- /* father: ... visited
- dst: visited ... udata mt */
- lua_pop(father, 1);
- /* father: ... */
- lua_pop(src, 3);
+ sglua_copy_table(src, dst);
+ /* src: ... udata mt
+ dst: ... udata mt */
+ lua_pop(src, 1);
/* src: ... udata */
-
- /* TODO make helper functions for this kind of operations */
- }
- else {
- XBT_DEBUG("%sI have no father", sglua_get_spaces(indent));
- sglua_move_value_impl(src, dst, "metatable");
- /* src: ... udata
- dst: visited ... udata mt */
- }
lua_setmetatable(dst, -2);
- /* dst: visited ... udata */
+ /* dst: ... udata */
XBT_DEBUG("%sMetatable of userdata copied", sglua_get_spaces(indent));
}
}
/**
- * @brief This operation is not supported (yet?) so this function pushes nil.
+ * @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("Cannot copy a thread from the source state.");
+ 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 father state.
+ * @brief Copies a global value or a registry value from the maestro state.
*
- * The state L must have a father, i.e. it should have been created by
- * clone_lua_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 the father state and pushes it on the stack of L.
- * If the value does not exist in the father state either, nil is pushed.
+ * 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
* @param L the current state
* @return number of return values pushed (always 1)
*/
-static int l_get_from_father(lua_State *L) {
+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 */
+ /* L: table key */
XBT_DEBUG("__index of '%s' begins", key);
- /* want a global or a registry value? */
- int pseudo_index;
- if (lua_equal(L, 1, LUA_REGISTRYINDEX)) {
- /* registry */
- pseudo_index = LUA_REGISTRYINDEX;
- XBT_DEBUG("Will get the value from the registry of the father");
- }
- else {
- /* global */
- pseudo_index = LUA_GLOBALSINDEX;
- XBT_DEBUG("Will get the value from the globals of the father");
- }
-
/* get the father */
- lua_State* father = sglua_get_father(L);
-
- if (father == NULL) {
- XBT_WARN("This state has no father");
- lua_pop(L, 3);
- lua_pushnil(L);
- return 1;
+ 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 */
- /* get the list of visited tables */
- lua_pushstring(L, "simgrid.father_visited_tables");
- /* L: table key "simgrid.father_visited_tables" */
- lua_rawget(L, LUA_REGISTRYINDEX);
- /* L: table key visited */
- lua_insert(L, 1);
- /* L: visited table key */
+ /* L: table key */
- /* get the value from the father */
- lua_getfield(father, pseudo_index, key);
- /* father: ... value */
/* push the value onto the stack of L */
- sglua_move_value_impl(father, L, key);
- /* father: ...
- L: visited table key value */
- lua_remove(L, 1);
- /* L: table key value */
+ sglua_move_value(maestro, L);
+ /* maestro: ...
+ L: table key value */
/* prepare the return value of __index */
lua_pushvalue(L, -1);
}
/**
- * @brief Creates a new Lua state and get its environment from an existing state.
+ * @brief Creates a new Lua state and get its environment from the maestro
+ * state.
*
- * The state created is independent from the existing one and has its own
- * copies of global and registry values.
+ * 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?
*
- * @param father an existing state
* @return the state created
*/
-lua_State* sglua_clone_state(lua_State *father) {
+lua_State* sglua_clone_maestro(void) {
/* create the new state */
lua_State *L = luaL_newstate();
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_father); /* thread newenv mt reg f */
+ 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_setfenv(L, -2); /* thread */
- lua_pop(L, 1); /* -- */
-
- /* set a pointer to the father */
- lua_pushstring(L, "simgrid.father"); /* "simgrid.father" */
- lua_pushlightuserdata(L, father); /* "simgrid.father" father */
- lua_rawset(L, LUA_REGISTRYINDEX);
- /* -- */
-
- /* create the table of visited tables from the father */
- lua_pushstring(L, "simgrid.father_visited_tables");
- /* "simgrid.father_visited_tables" */
- lua_newtable(L); /* "simgrid.father_visited_tables" visited */
- lua_rawset(L, LUA_REGISTRYINDEX);
- /* -- */
-
- /* create the table of my own visited tables */
- lua_pushstring(L, "simgrid.visited_tables");
- /* "simgrid.visited_tables" */
- lua_newtable(L); /* "simgrid.visited_tables" visited */
+ 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);
/* -- */
- /* open the standard libs (theoretically, this is not necessary as they can
- * be inherited like any global values, but without a proper support of
- * closures, iterators like ipairs don't work). */
- XBT_DEBUG("Metatable of globals and registry set, opening standard libraries now");
- luaL_openlibs(L);
+ /* opening the standard libs is not necessary as they are
+ * inherited like any global values */
+ /* luaL_openlibs(L); */
XBT_DEBUG("New state created");