From: Christophe Thiéry Date: Thu, 29 Sep 2011 11:05:05 +0000 (+0200) Subject: Lua: separate bindings, state cloning functions and helper functions X-Git-Tag: exp_20120216~558^2~15^2~8 X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/4610b103f5b664648c716031782165da1e6fbd41 Lua: separate bindings, state cloning functions and helper functions --- diff --git a/buildtools/Cmake/DefinePackages.cmake b/buildtools/Cmake/DefinePackages.cmake index ea1f093367..d363791d69 100644 --- a/buildtools/Cmake/DefinePackages.cmake +++ b/buildtools/Cmake/DefinePackages.cmake @@ -334,6 +334,8 @@ set(LUA_SRC src/bindings/lua/simgrid_lua.c src/bindings/lua/lua_stub_generator.c src/bindings/lua/lua_console.c + src/bindings/lua/lua_utils.c + src/bindings/lua/lua_state_cloner.c ) set(TRACING_SRC diff --git a/src/bindings/lua/lua_state_cloner.c b/src/bindings/lua/lua_state_cloner.c new file mode 100644 index 0000000000..d585d73b5d --- /dev/null +++ b/src/bindings/lua/lua_state_cloner.c @@ -0,0 +1,522 @@ +/* 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. */ + +/* SimGrid Lua state management */ + +#include "lua_state_cloner.h" +#include "lua_utils.h" +#include "xbt.h" +#include "xbt/log.h" +#include +#include + +XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua_state_cloner, lua, "Lua state management"); + +static lua_State* sglua_get_father(lua_State* L); +static void sglua_move_value_impl(lua_State* src, lua_State* dst, const char* name); +static int l_get_from_father(lua_State* L); + +/** + * @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() + */ +static lua_State* sglua_get_father(lua_State* L) { + + /* ... */ + lua_pushstring(L, "simgrid.father"); + /* ... "simgrid.father" */ + lua_rawget(L, LUA_REGISTRYINDEX); + /* ... father */ + lua_State* father = lua_touserdata(L, -1); + lua_pop(L, 1); + /* ... */ + return father; +} + +/** + * @brief Pops a value from a state and pushes it onto the stack of another + * state. + * + * @param src the source state + * @param dst the destination state + */ +void sglua_move_value(lua_State* src, lua_State* dst) { + + if (src != dst) { + + /* 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); + } +} + +/** + * @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. 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. + * + * TODO: add support of closures + * + * @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 + */ +static void sglua_move_value_impl(lua_State* src, lua_State *dst, const char* name) { + + 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); + indent += 2; + + sglua_stack_dump("src before copying a value (should be ... value): ", src); + sglua_stack_dump("dst before copying a value (should be visited ...): ", dst); + + switch (lua_type(src, -1)) { + /* TODO implement the copy of each type in a separate function */ + + case LUA_TNIL: + lua_pushnil(dst); + break; + + case LUA_TNUMBER: + lua_pushnumber(dst, lua_tonumber(src, -1)); + break; + + case LUA_TBOOLEAN: + lua_pushboolean(dst, lua_toboolean(src, -1)); + break; + + case LUA_TSTRING: + /* no worries about memory: lua_pushstring makes a copy */ + lua_pushstring(dst, lua_tostring(src, -1)); + break; + + case LUA_TFUNCTION: + /* it's a function that does not exist yet in L2 */ + + 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); + } + else { + /* it's a Lua function: dump it from src */ + XBT_DEBUG("%sDumping Lua function '%s'", sglua_get_spaces(indent), name); + + s_buffer_t buffer; + buffer.capacity = 64; + 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); + xbt_assert(!error, "Failed to dump function '%s' from the source state: error %d", + name, error); + + /* load the chunk into dst */ + error = luaL_loadbuffer(dst, buffer.data, buffer.size, name); + xbt_assert(!error, "Failed to load function '%s' into the destination state: %s", + name, lua_tostring(dst, -1)); + XBT_DEBUG("%sFunction '%s' successfully loaded", sglua_get_spaces(indent), name); + } + break; + + case LUA_TTABLE: + + /* 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 */ + } + else { + XBT_DEBUG("%sFirst visit of this table (%p)", sglua_get_spaces(indent), + lua_topointer(src, -1)); + /* dst: visited ... nil */ + lua_pop(dst, 1); + /* dst: visited ... */ + + /* first visit: create the new table in dst */ + lua_newtable(dst); + /* dst: visited ... table */ + + /* mark the table as visited 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); + + /* copy the metatable if any */ + int has_meta_table = lua_getmetatable(src, -1); + /* src: ... table mt? */ + if (has_meta_table) { + XBT_DEBUG("%sCopying metatable", sglua_get_spaces(indent)); + /* src: ... table mt */ + sglua_move_value_impl(src, dst, "metatable"); + /* src: ... table + dst: visited ... table mt */ + lua_setmetatable(dst, -2); + /* dst: visited ... table */ + } + else { + 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); + + /* 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 visited ... 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_impl(src, dst, sglua_tostring(src, -1)); + /* src: ... table key value + dst: visited ... 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 */ + 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 */ + + /* 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); + + XBT_DEBUG("%sTable element copied", sglua_get_spaces(indent)); + } + XBT_DEBUG("%sFinished traversing the table", sglua_get_spaces(indent)); + } + break; + + case LUA_TLIGHTUSERDATA: + lua_pushlightuserdata(dst, lua_touserdata(src, -1)); + break; + + case LUA_TUSERDATA: + { + /* copy the data */ + /* src: ... udata + dst: visited ... */ + size_t size = lua_objlen(src, -1); + void* src_block = lua_touserdata(src, -1); + void* dst_block = lua_newuserdata(dst, size); + /* dst: visited ... 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 */ + 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); + /* 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 */ + + XBT_DEBUG("%sMetatable of userdata copied", sglua_get_spaces(indent)); + } + else { + XBT_DEBUG("%sNo metatable for this userdata", + sglua_get_spaces(indent)); + /* src: ... udata */ + } + } + break; + + case LUA_TTHREAD: + XBT_WARN("Cannot copy a thread from the source state."); + lua_pushnil(dst); + break; + } + + /* pop the value from src */ + lua_pop(src, 1); + + 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); +} + +/** + * @brief Copies a global value or a registry value from the father state. + * + * The state L must have a father, i.e. it should have been created by + * clone_lua_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. + * + * 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_father(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); + + /* 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; + } + /* 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 */ + + /* 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 */ + + /* 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 an existing state. + * + * The state created is independent from the existing one 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) { + + /* 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_father); /* 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_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); + + XBT_DEBUG("New state created"); + + return L; +} diff --git a/src/bindings/lua/lua_state_cloner.h b/src/bindings/lua/lua_state_cloner.h new file mode 100644 index 0000000000..eb97fd8db0 --- /dev/null +++ b/src/bindings/lua/lua_state_cloner.h @@ -0,0 +1,13 @@ +/* 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. */ + +/* SimGrid Lua state management */ + + +#include + +void sglua_move_value(lua_State* src, lua_State* dst); +lua_State* sglua_clone_state(lua_State* L); diff --git a/src/bindings/lua/lua_utils.c b/src/bindings/lua/lua_utils.c new file mode 100644 index 0000000000..55721bc7c4 --- /dev/null +++ b/src/bindings/lua/lua_utils.c @@ -0,0 +1,162 @@ +/* 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. */ + +/* SimGrid Lua helper functions */ + +#include "lua_utils.h" +#include "xbt.h" +#include "xbt/log.h" + +XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua_utils, lua, "Lua helper functions"); + +/** + * @brief Returns a string representation of a value in the Lua stack. + * + * This function is for debugging purposes. + * It always returns the same pointer. + * + * @param L the Lua state + * @param index index in the stack + * @return a string representation of the value at this index + */ +const char* sglua_tostring(lua_State* L, int index) { + + static char buff[64]; + + switch (lua_type(L, index)) { + + case LUA_TNIL: + sprintf(buff, "nil"); + break; + + case LUA_TNUMBER: + sprintf(buff, "%.3f", lua_tonumber(L, index)); + break; + + case LUA_TBOOLEAN: + sprintf(buff, "%s", lua_toboolean(L, index) ? "true" : "false"); + break; + + case LUA_TSTRING: + snprintf(buff, 63, "'%s'", lua_tostring(L, index)); + break; + + case LUA_TFUNCTION: + if (lua_iscfunction(L, index)) { + sprintf(buff, "C-function"); + } + else { + sprintf(buff, "function"); + } + break; + + case LUA_TTABLE: + sprintf(buff, "table(%p)", lua_topointer(L, index)); + break; + + case LUA_TLIGHTUSERDATA: + case LUA_TUSERDATA: + sprintf(buff, "userdata(%p)", lua_touserdata(L, index)); + break; + + case LUA_TTHREAD: + sprintf(buff, "thread"); + break; + } + return buff; +} + +/** + * @brief Returns a string representation of a key-value pair. + * + * This function is for debugging purposes. + * It always returns the same pointer. + * + * @param L the Lua state + * @param key_index index of the key + * @param value_index index of the value + * @return a string representation of the key-value pair + */ +const char* sglua_keyvalue_tostring(lua_State* L, int key_index, int value_index) { + + static char buff[64]; + /* value_tostring also always returns the same pointer */ + int len = snprintf(buff, 63, "[%s] -> ", sglua_tostring(L, key_index)); + snprintf(buff + len, 63 - len, "%s", sglua_tostring(L, value_index)); + return buff; +} + +/** + * @brief Returns a string composed of the specified number of spaces. + * + * This function can be used to indent strings for debugging purposes. + * It always returns the same pointer. + * + * @param length length of the string + * @return a string of this length with only spaces + */ +const char* sglua_get_spaces(int length) { + + static char spaces[128]; + + xbt_assert(length < 128); + memset(spaces, ' ', length); + spaces[length] = '\0'; + return spaces; +} + +/** + * @brief Dumps the Lua stack if debug logs are enabled. + * @param msg a message to print + * @param L a Lua state + */ +void sglua_stack_dump(const char* msg, lua_State* L) +{ + if (XBT_LOG_ISENABLED(lua_utils, xbt_log_priority_debug)) { + char buff[2048]; + char* p = buff; + int i; + int top = lua_gettop(L); + + //if (1) return; + + fflush(stdout); + + p[0] = '\0'; + for (i = 1; i <= top; i++) { /* repeat for each level */ + + p += sprintf(p, "%s", sglua_tostring(L, i)); + p += sprintf(p, " "); /* put a separator */ + } + XBT_DEBUG("%s%s", msg, buff); + } +} + +/** + * @brief Writes the specified data into a memory buffer. + * + * This function is a valid lua_Writer that writes into a memory buffer passed + * as userdata. + * TODO: use a dynar as userdata + * + * @param L a lua state + * @param source some data + * @param sz number of bytes of data + * @param user_data the memory buffer to write + */ +int sglua_memory_writer(lua_State* L, const void* source, size_t size, + void* userdata) { + + buffer_t buffer = (buffer_t) userdata; + while (buffer->capacity < buffer->size + size) { + buffer->capacity *= 2; + buffer->data = xbt_realloc(buffer->data, buffer->capacity); + } + memcpy(buffer->data + buffer->size, source, size); + buffer->size += size; + + return 0; +} diff --git a/src/bindings/lua/lua_utils.h b/src/bindings/lua/lua_utils.h new file mode 100644 index 0000000000..b36e217d6e --- /dev/null +++ b/src/bindings/lua/lua_utils.h @@ -0,0 +1,26 @@ +/* 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. */ + +/* SimGrid Lua helper functions */ + +#include + +/** + * @brief A chunk of memory. + * + * TODO replace this by a dynar + */ +typedef struct s_buffer { + char* data; + size_t size; + size_t capacity; +} s_buffer_t, *buffer_t; + +const char* sglua_tostring(lua_State* L, int index); +const char* sglua_keyvalue_tostring(lua_State* L, int key_index, int value_index); +void sglua_stack_dump(const char *msg, lua_State* L); +const char* sglua_get_spaces(int length); +int sglua_memory_writer(lua_State* L, const void* source, size_t size, void* userdata); diff --git a/src/bindings/lua/simgrid_lua.c b/src/bindings/lua/simgrid_lua.c index 17dda691fc..2dbb971a4b 100644 --- a/src/bindings/lua/simgrid_lua.c +++ b/src/bindings/lua/simgrid_lua.c @@ -1,14 +1,15 @@ -/* 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. */ + +/* SimGrid Lua bindings */ + #include "simgrid_lua.h" -#include // memcpy +#include "lua_state_cloner.h" -XBT_LOG_NEW_DEFAULT_SUBCATEGORY(lua, bindings, "Lua Bindings"); +XBT_LOG_NEW_DEFAULT_CATEGORY(lua, "Lua Bindings"); static lua_State *lua_maestro_state; @@ -20,673 +21,8 @@ static lua_State *lua_maestro_state; #define AS_MODULE_NAME "simgrid.AS" #define TRACE_MODULE_NAME "simgrid.Trace" -/** - * @brief A chunk of memory. - * - * TODO replace this by a dynar - */ -typedef struct s_buffer { - char* data; - size_t size; - size_t capacity; -} s_buffer_t, *buffer_t; - -static const char* value_tostring(lua_State* L, int index); -static const char* keyvalue_tostring(lua_State* L, int key_index, int value_index); -static void stack_dump(const char *msg, lua_State* L); -static int writer(lua_State* L, const void* source, size_t size, void* userdata); -static lua_State* get_father(lua_State* L); -static void move_value(lua_State* src, lua_State* dst); -static void move_value_impl(lua_State* src, lua_State* dst, const char* name); -static int l_get_from_father(lua_State* L); -static lua_State *clone_lua_state(lua_State* L); -static m_task_t check_task(lua_State *L, int index); static void register_c_functions(lua_State *L); -/* ********************************************************************************* */ -/* helper functions */ -/* ********************************************************************************* */ - -/** - * @brief Returns a string representation of a value in the Lua stack. - * - * This function is for debugging purposes. - * It always returns the same pointer. - * - * @param L the Lua state - * @param index index in the stack - * @return a string representation of the value at this index - */ -static const char* value_tostring(lua_State* L, int index) { - - static char buff[64]; - - switch (lua_type(L, index)) { - - case LUA_TNIL: - sprintf(buff, "nil"); - break; - - case LUA_TNUMBER: - sprintf(buff, "%.3f", lua_tonumber(L, index)); - break; - - case LUA_TBOOLEAN: - sprintf(buff, "%s", lua_toboolean(L, index) ? "true" : "false"); - break; - - case LUA_TSTRING: - snprintf(buff, 63, "'%s'", lua_tostring(L, index)); - break; - - case LUA_TFUNCTION: - if (lua_iscfunction(L, index)) { - sprintf(buff, "C-function"); - } - else { - sprintf(buff, "function"); - } - break; - - case LUA_TTABLE: - sprintf(buff, "table(%p)", lua_topointer(L, index)); - break; - - case LUA_TLIGHTUSERDATA: - case LUA_TUSERDATA: - sprintf(buff, "userdata(%p)", lua_touserdata(L, index)); - break; - - case LUA_TTHREAD: - sprintf(buff, "thread"); - break; - } - return buff; -} - -/** - * @brief Returns a string representation of a key-value pair. - * - * This function is for debugging purposes. - * It always returns the same pointer. - * - * @param L the Lua state - * @param key_index index of the key - * @param value_index index of the value - * @return a string representation of the key-value pair - */ -static const char* keyvalue_tostring(lua_State* L, int key_index, int value_index) { - - static char buff[64]; - /* value_tostring also always returns the same pointer */ - int len = snprintf(buff, 63, "[%s] -> ", value_tostring(L, key_index)); - snprintf(buff + len, 63 - len, "%s", value_tostring(L, value_index)); - return buff; -} - -/** - * @brief Returns a string composed of the specified number of spaces. - * - * This function is for debugging purposes. - * It always returns the same pointer. - * - * @param length length of the string - * @return a string of this length with only spaces - */ -static const char* get_spaces(int length) { - - static char spaces[128]; - - xbt_assert(length < 128); - memset(spaces, ' ', length); - spaces[length] = '\0'; - return spaces; -} - -/** - * @brief Dumps the Lua stack if debug logs are enabled. - * @param msg a message to print - * @param L a Lua state - */ -static void stack_dump(const char* msg, lua_State* L) -{ - if (XBT_LOG_ISENABLED(lua, xbt_log_priority_debug)) { - char buff[2048]; - char* p = buff; - int i; - int top = lua_gettop(L); - - //if (1) return; - - fflush(stdout); - - p[0] = '\0'; - for (i = 1; i <= top; i++) { /* repeat for each level */ - - p += sprintf(p, "%s", value_tostring(L, i)); - p += sprintf(p, " "); /* put a separator */ - } - XBT_DEBUG("%s%s", msg, buff); - } -} - -/** - * @brief Writes the specified data into a memory buffer. - * - * This function is a valid lua_Writer that writes into a memory buffer passed - * as userdata. - * - * @param L a lua state - * @param source some data - * @param sz number of bytes of data - * @param user_data the memory buffer to write - */ -static int writer(lua_State* L, const void* source, size_t size, void* userdata) { - - buffer_t buffer = (buffer_t) userdata; - while (buffer->capacity < buffer->size + size) { - buffer->capacity *= 2; - buffer->data = xbt_realloc(buffer->data, buffer->capacity); - } - memcpy(buffer->data + buffer->size, source, size); - buffer->size += size; - - return 0; -} - -/** - * @brief Returns the father of a state. - * @param L a Lua state - * @return its father - */ -static lua_State* get_father(lua_State* L) { - - /* ... */ - lua_pushstring(L, "simgrid.father"); - /* ... "simgrid.father" */ - lua_rawget(L, LUA_REGISTRYINDEX); - /* ... father */ - lua_State* father = lua_touserdata(L, -1); - lua_pop(L, 1); - /* ... */ - return father; -} - -/** - * @brief Pops a value from a state and pushes it onto the stack of another - * state. - * - * @param src the source state - * @param dst the destination state - */ -static void move_value(lua_State* src, lua_State* dst) { - - if (src != dst) { - - /* 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 ... */ - - move_value_impl(src, dst, value_tostring(src, -1)); - /* src: ... - dst: visited ... value */ - lua_remove(dst, 1); - /* dst: ... value */ - stack_dump("src after xmove: ", src); - stack_dump("dst after xmove: ", dst); - } -} - -/** - * @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. 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. - * - * TODO: add support of closures - * - * @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 - */ -static void move_value_impl(lua_State* src, lua_State *dst, const char* name) { - - 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", get_spaces(indent), name); - indent += 2; - - stack_dump("src before copying a value (should be ... value): ", src); - stack_dump("dst before copying a value (should be visited ...): ", dst); - - switch (lua_type(src, -1)) { - /* TODO implement the copy of each type in a separate function */ - - case LUA_TNIL: - lua_pushnil(dst); - break; - - case LUA_TNUMBER: - lua_pushnumber(dst, lua_tonumber(src, -1)); - break; - - case LUA_TBOOLEAN: - lua_pushboolean(dst, lua_toboolean(src, -1)); - break; - - case LUA_TSTRING: - /* no worries about memory: lua_pushstring makes a copy */ - lua_pushstring(dst, lua_tostring(src, -1)); - break; - - case LUA_TFUNCTION: - /* it's a function that does not exist yet in L2 */ - - 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); - } - else { - /* it's a Lua function: dump it from src */ - XBT_DEBUG("%sDumping Lua function '%s'", get_spaces(indent), name); - - s_buffer_t buffer; - buffer.capacity = 64; - buffer.size = 0; - buffer.data = xbt_new(char, buffer.capacity); - - /* copy the binary chunk from src into a buffer */ - int error = lua_dump(src, writer, &buffer); - xbt_assert(!error, "Failed to dump function '%s' from the source state: error %d", - name, error); - - /* load the chunk into dst */ - error = luaL_loadbuffer(dst, buffer.data, buffer.size, name); - xbt_assert(!error, "Failed to load function '%s' into the destination state: %s", - name, lua_tostring(dst, -1)); - XBT_DEBUG("%sFunction '%s' successfully loaded", get_spaces(indent), name); - } - break; - - case LUA_TTABLE: - - /* 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)", - get_spaces(indent), lua_topointer(src, -1)); - /* dst: visited ... table */ - } - else { - XBT_DEBUG("%sFirst visit of this table (%p)", get_spaces(indent), - lua_topointer(src, -1)); - /* dst: visited ... nil */ - lua_pop(dst, 1); - /* dst: visited ... */ - - /* first visit: create the new table in dst */ - lua_newtable(dst); - /* dst: visited ... table */ - - /* mark the table as visited 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", get_spaces(indent)); - - stack_dump("dst after marking the table as visited (should be visited ... 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 metatable", get_spaces(indent)); - /* src: ... table mt */ - move_value_impl(src, dst, "metatable"); - /* src: ... table - dst: visited ... table mt */ - lua_setmetatable(dst, -2); - /* dst: visited ... table */ - } - else { - XBT_DEBUG("%sNo metatable", get_spaces(indent)); - } - - stack_dump("src before traversing the table (should be ... table): ", src); - stack_dump("dst before traversing the table (should be visited ... 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", get_spaces(indent), keyvalue_tostring(src, -2, -1)); - - stack_dump("src before copying table element (should be ... table key value): ", src); - stack_dump("dst before copying table element (should be visited ... 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", get_spaces(indent)); - move_value_impl(src, dst, value_tostring(src, -1)); - /* src: ... table key value - dst: visited ... table key */ - XBT_DEBUG("%sCopied the key part of the table element", get_spaces(indent)); - - /* copy the value */ - XBT_DEBUG("%sCopying the value part of the table element", get_spaces(indent)); - move_value_impl(src, dst, value_tostring(src, -1)); - /* src: ... table key - dst: visited ... table key value */ - XBT_DEBUG("%sCopied the value part of the table element", get_spaces(indent)); - indent -= 2; - - /* set the table element */ - lua_settable(dst, -3); - /* dst: visited ... table */ - - /* the key stays on top of src for next iteration */ - stack_dump("src before next iteration (should be ... table key): ", src); - stack_dump("dst before next iteration (should be visited ... table): ", dst); - - XBT_DEBUG("%sTable element copied", get_spaces(indent)); - } - XBT_DEBUG("%sFinished traversing the table", get_spaces(indent)); - } - break; - - case LUA_TLIGHTUSERDATA: - lua_pushlightuserdata(dst, lua_touserdata(src, -1)); - break; - - case LUA_TUSERDATA: - { - /* copy the data */ - /* src: ... udata - dst: visited ... */ - size_t size = lua_objlen(src, -1); - void* src_block = lua_touserdata(src, -1); - void* dst_block = lua_newuserdata(dst, size); - /* dst: visited ... 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)", get_spaces(indent), - lua_topointer(src, -1)); - /* src: ... udata mt */ - lua_State* father = get_father(dst); - - if (father != NULL && src != father && get_father(src) == father) { - XBT_DEBUG("%sGet the metatable from my father", 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 */ - move_value_impl(father, dst, "(father metatable)"); - /* father: ... visited - dst: visited ... udata mt */ - lua_pop(father, 1); - /* father: ... */ - lua_pop(src, 3); - /* src: ... udata */ - - /* TODO make helper functions for this kind of operations */ - } - else { - XBT_DEBUG("%sI have no father", get_spaces(indent)); - move_value_impl(src, dst, "metatable"); - /* src: ... udata - dst: visited ... udata mt */ - } - lua_setmetatable(dst, -2); - /* dst: visited ... udata */ - - XBT_DEBUG("%sMetatable of userdata copied", get_spaces(indent)); - } - else { - XBT_DEBUG("%sNo metatable for this userdata", get_spaces(indent)); - /* src: ... udata */ - } - } - break; - - case LUA_TTHREAD: - XBT_WARN("Cannot copy a thread from the source state."); - lua_pushnil(dst); - break; - } - - /* pop the value from src */ - lua_pop(src, 1); - - indent -= 2; - XBT_DEBUG("%sData copied", get_spaces(indent)); - - stack_dump("src after copying a value (should be ...): ", src); - stack_dump("dst after copying a value (should be visited ... value): ", dst); -} - -/** - * @brief Copies a global value or a registry value from the father state. - * - * The state L must have a father, i.e. it should have been created by - * clone_lua_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. - * - * 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_father(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); - - /* 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 = get_father(L); - - if (father == NULL) { - XBT_WARN("This state has no father"); - lua_pop(L, 3); - lua_pushnil(L); - return 1; - } - /* 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 */ - - /* get the value from the father */ - lua_getfield(father, pseudo_index, key); - /* father: ... value */ - - /* push the value onto the stack of L */ - move_value_impl(father, L, key); - /* father: ... - L: visited table key value */ - lua_remove(L, 1); - /* 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, value_tostring(L, -1)); - - return 1; -} - -/** - * @brief Creates a new Lua state and get its environment from an existing state. - * - * The state created is independent from the existing one and has its own - * copies of global variables and functions. - * However, the global variables and functions 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. - * - * @param father an existing state - * @return the state created - */ -static lua_State* clone_lua_state(lua_State *father) { - - /* 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_father); /* 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_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); - - XBT_DEBUG("New state created"); - - return L; -} - /* static void *my_checkudata (lua_State *L, int ud, const char *tname) { void *p = lua_touserdata(L, ud); @@ -847,15 +183,7 @@ static int Task_recv_with_timeout(lua_State *L) if (res == MSG_OK) { lua_State *sender_stack = MSG_task_get_data(tk); - - stack_dump("sender before moving data: ", sender_stack); - stack_dump("receiver before moving data: ", L); - - move_value(sender_stack, L); // copy the data directly from sender's stack - - stack_dump("sender after moving data: ", sender_stack); - stack_dump("receiver after moving data: ", L); - + sglua_move_value(sender_stack, L); // copy the data directly from sender's stack MSG_task_set_data(tk, NULL); } else { @@ -1194,7 +522,7 @@ static int run_lua_code(int argc, char **argv) { XBT_DEBUG("Run lua code %s", argv[0]); - lua_State *L = clone_lua_state(lua_maestro_state); + lua_State *L = sglua_clone_state(lua_maestro_state); int res = 1; /* start the function */