/*

 * SPDX-License-Identifier: ISC

 *

 * Copyright 2023, Sergey Bronnikov.

 */

#include <stdint.h>

#include <stdlib.h> /* malloc, free */

#include <string.h> /* memcpy */

#include "lua.h"

#include "lualib.h"

#include "lauxlib.h"

/*

 * The main purpose of the test is testing Lua frontend (lexer, parser).

 * The test doesn't execute a loaded chunk to be quite fast.

 */

int

LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)

{

  lua_State *L = luaL_newstate();

  if (L == NULL)

    return 0;

  /*

   * The string "mode" controls whether the chunk can be text or binary

   * (that is, a precompiled chunk). It may be the string "b" (only binary

   * chunks), "t" (only text chunks), or "bt" (both binary and text). The

   * default is "bt".

   * Lua runtime (at least PUC Rio Lua and LuaJIT) has bytecode and Lua

   * parsers. It is desired to test both parsers, however, in LuaJIT

   * bytecode parser failed with assertion:

   *

   * LuaJIT ASSERT lj_bcread.c:123: bcread_byte: buffer read overflow

   *

   * so in LuaJIT only text mode is used and therefore only text parser is

   * tested.

   */

#ifdef LUAJIT

  const char *mode = "t";

#else

  const char *mode = "bt";

#endif /* LUAJIT */

  luaL_loadbufferx(L, (const char *)data, size, "fuzz", mode);

  lua_settop(L, 0);

  lua_close(L);

  return 0;

}