diff options
Diffstat (limited to 'examples/redis-unstable/src/function_lua.c')
| -rw-r--r-- | examples/redis-unstable/src/function_lua.c | 513 |
1 files changed, 0 insertions, 513 deletions
diff --git a/examples/redis-unstable/src/function_lua.c b/examples/redis-unstable/src/function_lua.c deleted file mode 100644 index 785f825..0000000 --- a/examples/redis-unstable/src/function_lua.c +++ /dev/null @@ -1,513 +0,0 @@ -/* - * Copyright (c) 2021-Present, Redis Ltd. - * All rights reserved. - * - * Licensed under your choice of (a) the Redis Source Available License 2.0 - * (RSALv2); or (b) the Server Side Public License v1 (SSPLv1); or (c) the - * GNU Affero General Public License v3 (AGPLv3). - */ - -/* - * function_lua.c unit provides the Lua engine functionality. - * Including registering the engine and implementing the engine - * callbacks: - * * Create a function from blob (usually text) - * * Invoke a function - * * Free function memory - * * Get memory usage - * - * Uses script_lua.c to run the Lua code. - */ - -#include "functions.h" -#include "script_lua.h" -#include <lua.h> -#include <lauxlib.h> -#include <lualib.h> -#if defined(USE_JEMALLOC) -#include <lstate.h> -#endif - -#define LUA_ENGINE_NAME "LUA" -#define REGISTRY_ENGINE_CTX_NAME "__ENGINE_CTX__" -#define REGISTRY_ERROR_HANDLER_NAME "__ERROR_HANDLER__" -#define REGISTRY_LOAD_CTX_NAME "__LIBRARY_CTX__" -#define LIBRARY_API_NAME "__LIBRARY_API__" -#define GLOBALS_API_NAME "__GLOBALS_API__" - -static int gc_count = 0; /* Counter for the number of GC requests, reset after each GC execution */ - -/* Lua engine ctx */ -typedef struct luaEngineCtx { - lua_State *lua; -} luaEngineCtx; - -/* Lua function ctx */ -typedef struct luaFunctionCtx { - /* Special ID that allows getting the Lua function object from the Lua registry */ - int lua_function_ref; -} luaFunctionCtx; - -typedef struct loadCtx { - functionLibInfo *li; - monotime start_time; - size_t timeout; -} loadCtx; - -typedef struct registerFunctionArgs { - sds name; - sds desc; - luaFunctionCtx *lua_f_ctx; - uint64_t f_flags; -} registerFunctionArgs; - -/* Hook for FUNCTION LOAD execution. - * Used to cancel the execution in case of a timeout (500ms). - * This execution should be fast and should only register - * functions so 500ms should be more than enough. */ -static void luaEngineLoadHook(lua_State *lua, lua_Debug *ar) { - UNUSED(ar); - loadCtx *load_ctx = luaGetFromRegistry(lua, REGISTRY_LOAD_CTX_NAME); - serverAssert(load_ctx); /* Only supported inside script invocation */ - uint64_t duration = elapsedMs(load_ctx->start_time); - if (load_ctx->timeout > 0 && duration > load_ctx->timeout) { - lua_sethook(lua, luaEngineLoadHook, LUA_MASKLINE, 0); - - luaPushError(lua,"FUNCTION LOAD timeout"); - luaError(lua); - } -} - -/* - * Compile a given blob and save it on the registry. - * Return a function ctx with Lua ref that allows to later retrieve the - * function from the registry. - * - * Return NULL on compilation error and set the error to the err variable - */ -static int luaEngineCreate(void *engine_ctx, functionLibInfo *li, sds blob, size_t timeout, sds *err) { - int ret = C_ERR; - luaEngineCtx *lua_engine_ctx = engine_ctx; - lua_State *lua = lua_engine_ctx->lua; - - /* set load library globals */ - lua_getmetatable(lua, LUA_GLOBALSINDEX); - lua_enablereadonlytable(lua, -1, 0); /* disable global protection */ - lua_getfield(lua, LUA_REGISTRYINDEX, LIBRARY_API_NAME); - lua_setfield(lua, -2, "__index"); - lua_enablereadonlytable(lua, LUA_GLOBALSINDEX, 1); /* enable global protection */ - lua_pop(lua, 1); /* pop the metatable */ - - /* compile the code */ - if (luaL_loadbuffer(lua, blob, sdslen(blob), "@user_function")) { - *err = sdscatprintf(sdsempty(), "Error compiling function: %s", lua_tostring(lua, -1)); - lua_pop(lua, 1); /* pops the error */ - goto done; - } - serverAssert(lua_isfunction(lua, -1)); - - loadCtx load_ctx = { - .li = li, - .start_time = getMonotonicUs(), - .timeout = timeout, - }; - luaSaveOnRegistry(lua, REGISTRY_LOAD_CTX_NAME, &load_ctx); - - lua_sethook(lua,luaEngineLoadHook,LUA_MASKCOUNT,100000); - /* Run the compiled code to allow it to register functions */ - if (lua_pcall(lua,0,0,0)) { - errorInfo err_info = {0}; - luaExtractErrorInformation(lua, &err_info); - *err = sdscatprintf(sdsempty(), "Error registering functions: %s", err_info.msg); - lua_pop(lua, 1); /* pops the error */ - luaErrorInformationDiscard(&err_info); - goto done; - } - - ret = C_OK; - -done: - /* restore original globals */ - lua_getmetatable(lua, LUA_GLOBALSINDEX); - lua_enablereadonlytable(lua, -1, 0); /* disable global protection */ - lua_getfield(lua, LUA_REGISTRYINDEX, GLOBALS_API_NAME); - lua_setfield(lua, -2, "__index"); - lua_enablereadonlytable(lua, LUA_GLOBALSINDEX, 1); /* enable global protection */ - lua_pop(lua, 1); /* pop the metatable */ - - lua_sethook(lua,NULL,0,0); /* Disable hook */ - luaSaveOnRegistry(lua, REGISTRY_LOAD_CTX_NAME, NULL); - luaGC(lua, &gc_count); - return ret; -} - -/* - * Invole the give function with the given keys and args - */ -static void luaEngineCall(scriptRunCtx *run_ctx, - void *engine_ctx, - void *compiled_function, - robj **keys, - size_t nkeys, - robj **args, - size_t nargs) -{ - luaEngineCtx *lua_engine_ctx = engine_ctx; - lua_State *lua = lua_engine_ctx->lua; - luaFunctionCtx *f_ctx = compiled_function; - - /* Push error handler */ - lua_pushstring(lua, REGISTRY_ERROR_HANDLER_NAME); - lua_gettable(lua, LUA_REGISTRYINDEX); - - lua_rawgeti(lua, LUA_REGISTRYINDEX, f_ctx->lua_function_ref); - - serverAssert(lua_isfunction(lua, -1)); - - luaCallFunction(run_ctx, lua, keys, nkeys, args, nargs, 0); - lua_pop(lua, 1); /* Pop error handler */ - luaGC(lua, &gc_count); -} - -static size_t luaEngineGetUsedMemoy(void *engine_ctx) { - luaEngineCtx *lua_engine_ctx = engine_ctx; - return luaMemory(lua_engine_ctx->lua); -} - -static size_t luaEngineFunctionMemoryOverhead(void *compiled_function) { - return zmalloc_size(compiled_function); -} - -static size_t luaEngineMemoryOverhead(void *engine_ctx) { - luaEngineCtx *lua_engine_ctx = engine_ctx; - return zmalloc_size(lua_engine_ctx); -} - -static void luaEngineFreeFunction(void *engine_ctx, void *compiled_function) { - luaEngineCtx *lua_engine_ctx = engine_ctx; - lua_State *lua = lua_engine_ctx->lua; - luaFunctionCtx *f_ctx = compiled_function; - lua_unref(lua, f_ctx->lua_function_ref); - zfree(f_ctx); -} - -static void luaEngineFreeCtx(void *engine_ctx) { - luaEngineCtx *lua_engine_ctx = engine_ctx; -#if defined(USE_JEMALLOC) - /* When lua is closed, destroy the previously used private tcache. */ - void *ud = (global_State*)G(lua_engine_ctx->lua)->ud; - unsigned int lua_tcache = (unsigned int)(uintptr_t)ud; -#endif - - lua_gc(lua_engine_ctx->lua, LUA_GCCOLLECT, 0); - lua_close(lua_engine_ctx->lua); - zfree(lua_engine_ctx); - -#if defined(USE_JEMALLOC) - je_mallctl("tcache.destroy", NULL, NULL, (void *)&lua_tcache, sizeof(unsigned int)); -#endif -} - -static void luaRegisterFunctionArgsInitialize(registerFunctionArgs *register_f_args, - sds name, - sds desc, - luaFunctionCtx *lua_f_ctx, - uint64_t flags) -{ - *register_f_args = (registerFunctionArgs){ - .name = name, - .desc = desc, - .lua_f_ctx = lua_f_ctx, - .f_flags = flags, - }; -} - -static void luaRegisterFunctionArgsDispose(lua_State *lua, registerFunctionArgs *register_f_args) { - sdsfree(register_f_args->name); - if (register_f_args->desc) sdsfree(register_f_args->desc); - lua_unref(lua, register_f_args->lua_f_ctx->lua_function_ref); - zfree(register_f_args->lua_f_ctx); -} - -/* Read function flags located on the top of the Lua stack. - * On success, return C_OK and set the flags to 'flags' out parameter - * Return C_ERR if encounter an unknown flag. */ -static int luaRegisterFunctionReadFlags(lua_State *lua, uint64_t *flags) { - int j = 1; - int ret = C_ERR; - int f_flags = 0; - while(1) { - lua_pushnumber(lua,j++); - lua_gettable(lua,-2); - int t = lua_type(lua,-1); - if (t == LUA_TNIL) { - lua_pop(lua,1); - break; - } - if (!lua_isstring(lua, -1)) { - lua_pop(lua,1); - goto done; - } - - const char *flag_str = lua_tostring(lua, -1); - int found = 0; - for (scriptFlag *flag = scripts_flags_def; flag->str ; ++flag) { - if (!strcasecmp(flag->str, flag_str)) { - f_flags |= flag->flag; - found = 1; - break; - } - } - /* pops the value to continue the iteration */ - lua_pop(lua,1); - if (!found) { - /* flag not found */ - goto done; - } - } - - *flags = f_flags; - ret = C_OK; - -done: - return ret; -} - -static int luaRegisterFunctionReadNamedArgs(lua_State *lua, registerFunctionArgs *register_f_args) { - char *err = NULL; - sds name = NULL; - sds desc = NULL; - luaFunctionCtx *lua_f_ctx = NULL; - uint64_t flags = 0; - if (!lua_istable(lua, 1)) { - err = "calling redis.register_function with a single argument is only applicable to Lua table (representing named arguments)."; - goto error; - } - - /* Iterating on all the named arguments */ - lua_pushnil(lua); - while (lua_next(lua, -2)) { - /* Stack now: table, key, value */ - if (!lua_isstring(lua, -2)) { - err = "named argument key given to redis.register_function is not a string"; - goto error; - } - const char *key = lua_tostring(lua, -2); - if (!strcasecmp(key, "function_name")) { - if (!(name = luaGetStringSds(lua, -1))) { - err = "function_name argument given to redis.register_function must be a string"; - goto error; - } - } else if (!strcasecmp(key, "description")) { - if (!(desc = luaGetStringSds(lua, -1))) { - err = "description argument given to redis.register_function must be a string"; - goto error; - } - } else if (!strcasecmp(key, "callback")) { - if (!lua_isfunction(lua, -1)) { - err = "callback argument given to redis.register_function must be a function"; - goto error; - } - int lua_function_ref = luaL_ref(lua, LUA_REGISTRYINDEX); - - lua_f_ctx = zmalloc(sizeof(*lua_f_ctx)); - lua_f_ctx->lua_function_ref = lua_function_ref; - continue; /* value was already popped, so no need to pop it out. */ - } else if (!strcasecmp(key, "flags")) { - if (!lua_istable(lua, -1)) { - err = "flags argument to redis.register_function must be a table representing function flags"; - goto error; - } - if (luaRegisterFunctionReadFlags(lua, &flags) != C_OK) { - err = "unknown flag given"; - goto error; - } - } else { - /* unknown argument was given, raise an error */ - err = "unknown argument given to redis.register_function"; - goto error; - } - lua_pop(lua, 1); /* pop the value to continue the iteration */ - } - - if (!name) { - err = "redis.register_function must get a function name argument"; - goto error; - } - - if (!lua_f_ctx) { - err = "redis.register_function must get a callback argument"; - goto error; - } - - luaRegisterFunctionArgsInitialize(register_f_args, name, desc, lua_f_ctx, flags); - - return C_OK; - -error: - if (name) sdsfree(name); - if (desc) sdsfree(desc); - if (lua_f_ctx) { - lua_unref(lua, lua_f_ctx->lua_function_ref); - zfree(lua_f_ctx); - } - luaPushError(lua, err); - return C_ERR; -} - -static int luaRegisterFunctionReadPositionalArgs(lua_State *lua, registerFunctionArgs *register_f_args) { - char *err = NULL; - sds name = NULL; - sds desc = NULL; - luaFunctionCtx *lua_f_ctx = NULL; - if (!(name = luaGetStringSds(lua, 1))) { - err = "first argument to redis.register_function must be a string"; - goto error; - } - - if (!lua_isfunction(lua, 2)) { - err = "second argument to redis.register_function must be a function"; - goto error; - } - - int lua_function_ref = luaL_ref(lua, LUA_REGISTRYINDEX); - - lua_f_ctx = zmalloc(sizeof(*lua_f_ctx)); - lua_f_ctx->lua_function_ref = lua_function_ref; - - luaRegisterFunctionArgsInitialize(register_f_args, name, NULL, lua_f_ctx, 0); - - return C_OK; - -error: - if (name) sdsfree(name); - if (desc) sdsfree(desc); - luaPushError(lua, err); - return C_ERR; -} - -static int luaRegisterFunctionReadArgs(lua_State *lua, registerFunctionArgs *register_f_args) { - int argc = lua_gettop(lua); - if (argc < 1 || argc > 2) { - luaPushError(lua, "wrong number of arguments to redis.register_function"); - return C_ERR; - } - - if (argc == 1) { - return luaRegisterFunctionReadNamedArgs(lua, register_f_args); - } else { - return luaRegisterFunctionReadPositionalArgs(lua, register_f_args); - } -} - -static int luaRegisterFunction(lua_State *lua) { - registerFunctionArgs register_f_args = {0}; - - loadCtx *load_ctx = luaGetFromRegistry(lua, REGISTRY_LOAD_CTX_NAME); - if (!load_ctx) { - luaPushError(lua, "redis.register_function can only be called on FUNCTION LOAD command"); - return luaError(lua); - } - - if (luaRegisterFunctionReadArgs(lua, ®ister_f_args) != C_OK) { - return luaError(lua); - } - - sds err = NULL; - if (functionLibCreateFunction(register_f_args.name, register_f_args.lua_f_ctx, load_ctx->li, register_f_args.desc, register_f_args.f_flags, &err) != C_OK) { - luaRegisterFunctionArgsDispose(lua, ®ister_f_args); - luaPushError(lua, err); - sdsfree(err); - return luaError(lua); - } - - return 0; -} - -/* Initialize Lua engine, should be called once on start. */ -int luaEngineInitEngine(void) { - luaEngineCtx *lua_engine_ctx = zmalloc(sizeof(*lua_engine_ctx)); - lua_engine_ctx->lua = createLuaState(); - - luaRegisterRedisAPI(lua_engine_ctx->lua); - - /* Register the library commands table and fields and store it to registry */ - lua_newtable(lua_engine_ctx->lua); /* load library globals */ - lua_newtable(lua_engine_ctx->lua); /* load library `redis` table */ - - lua_pushstring(lua_engine_ctx->lua, "register_function"); - lua_pushcfunction(lua_engine_ctx->lua, luaRegisterFunction); - lua_settable(lua_engine_ctx->lua, -3); - - luaRegisterLogFunction(lua_engine_ctx->lua); - luaRegisterVersion(lua_engine_ctx->lua); - - luaSetErrorMetatable(lua_engine_ctx->lua); - lua_setfield(lua_engine_ctx->lua, -2, REDIS_API_NAME); - - luaSetErrorMetatable(lua_engine_ctx->lua); - luaSetTableProtectionRecursively(lua_engine_ctx->lua); /* protect load library globals */ - lua_setfield(lua_engine_ctx->lua, LUA_REGISTRYINDEX, LIBRARY_API_NAME); - - /* Save error handler to registry */ - lua_pushstring(lua_engine_ctx->lua, REGISTRY_ERROR_HANDLER_NAME); - char *errh_func = "local dbg = debug\n" - "debug = nil\n" - "local error_handler = function (err)\n" - " local i = dbg.getinfo(2,'nSl')\n" - " if i and i.what == 'C' then\n" - " i = dbg.getinfo(3,'nSl')\n" - " end\n" - " if type(err) ~= 'table' then\n" - " err = {err='ERR ' .. tostring(err)}" - " end" - " if i then\n" - " err['source'] = i.source\n" - " err['line'] = i.currentline\n" - " end" - " return err\n" - "end\n" - "return error_handler"; - luaL_loadbuffer(lua_engine_ctx->lua, errh_func, strlen(errh_func), "@err_handler_def"); - lua_pcall(lua_engine_ctx->lua,0,1,0); - lua_settable(lua_engine_ctx->lua, LUA_REGISTRYINDEX); - - lua_pushvalue(lua_engine_ctx->lua, LUA_GLOBALSINDEX); - luaSetErrorMetatable(lua_engine_ctx->lua); - luaSetTableProtectionRecursively(lua_engine_ctx->lua); /* protect globals */ - lua_pop(lua_engine_ctx->lua, 1); - - /* Save default globals to registry */ - lua_pushvalue(lua_engine_ctx->lua, LUA_GLOBALSINDEX); - lua_setfield(lua_engine_ctx->lua, LUA_REGISTRYINDEX, GLOBALS_API_NAME); - - /* save the engine_ctx on the registry so we can get it from the Lua interpreter */ - luaSaveOnRegistry(lua_engine_ctx->lua, REGISTRY_ENGINE_CTX_NAME, lua_engine_ctx); - - /* Create new empty table to be the new globals, we will be able to control the real globals - * using metatable */ - lua_newtable(lua_engine_ctx->lua); /* new globals */ - lua_newtable(lua_engine_ctx->lua); /* new globals metatable */ - lua_pushvalue(lua_engine_ctx->lua, LUA_GLOBALSINDEX); - lua_setfield(lua_engine_ctx->lua, -2, "__index"); - lua_enablereadonlytable(lua_engine_ctx->lua, -1, 1); /* protect the metatable */ - lua_setmetatable(lua_engine_ctx->lua, -2); - lua_enablereadonlytable(lua_engine_ctx->lua, -1, 1); /* protect the new global table */ - lua_replace(lua_engine_ctx->lua, LUA_GLOBALSINDEX); /* set new global table as the new globals */ - - /* Set metatables of basic types (string, number, nil etc.) readonly. */ - luaSetTableProtectionForBasicTypes(lua_engine_ctx->lua); - - engine *lua_engine = zmalloc(sizeof(*lua_engine)); - *lua_engine = (engine) { - .engine_ctx = lua_engine_ctx, - .create = luaEngineCreate, - .call = luaEngineCall, - .get_used_memory = luaEngineGetUsedMemoy, - .get_function_memory_overhead = luaEngineFunctionMemoryOverhead, - .get_engine_memory_overhead = luaEngineMemoryOverhead, - .free_function = luaEngineFreeFunction, - .free_ctx = luaEngineFreeCtx, - }; - return functionsRegisterEngine(LUA_ENGINE_NAME, lua_engine); -} |