lj_lex.h

/*
** Lexical analyzer.
** Copyright (C) 2005-2017 Mike Pall. See Copyright Notice in luajit.h
*/

#ifndef _LJ_LEX_H
#define _LJ_LEX_H

#include <stdarg.h>

#include "lj_obj.h"
#include "lj_err.h"

/* Lua lexer tokens. */
#define TKDEF(_, __) \
  _(and) _(break) _(do) _(else) _(elseif) _(end) _(false) \
  _(for) _(function) _(goto) _(if) _(in) _(local) _(nil) _(not) _(or) \
  _(repeat) _(return) _(then) _(true) _(until) _(while) \
  __(concat, ..) __(dots, ...) __(eq, ==) __(ge, >=) __(le, <=) __(ne, ~=) \
  __(label, ::) __(number, <number>) __(name, <name>) __(string, <string>) \
  __(eof, <eof>)

enum {
  TK_OFS = 256,
#define TKENUM1(name)       TK_##name,
#define TKENUM2(name, sym)  TK_##name,
TKDEF(TKENUM1, TKENUM2)
#undef TKENUM1
#undef TKENUM2
  TK_RESERVED = TK_while - TK_OFS
};

typedef int LexToken;

/* Combined bytecode ins/line. Only used during bytecode generation. */
typedef struct BCInsLine {
  BCIns ins;        /* Bytecode instruction. */
  BCLine line;      /* Line number for this bytecode. */
} BCInsLine;

/* Info for local variables. Only used during bytecode generation. */
typedef struct VarInfo {
  GCRef name;       /* Local variable name or goto/label name. */
  BCPos startpc;    /* First point where the local variable is active. */
  BCPos endpc;      /* First point where the local variable is dead. */
  uint8_t slot;     /* Variable slot. */
  uint8_t info;     /* Variable/goto/label info. */
} VarInfo;

/* Lua lexer state. */
typedef struct LexState {
  struct FuncState *fs; /* Current FuncState. Defined in lj_parse.c. */
  struct lua_State *L;  /* Lua state. */
  TValue tokenval;  /* Current token value. */
  TValue lookaheadval;  /* Lookahead token value. */
  int current;      /* Current character (charint). */
  LexToken token;   /* Current token. */
  LexToken lookahead;   /* Lookahead token. */
  MSize n;      /* Bytes left in input buffer. */
  const char *p;    /* Current position in input buffer. */
  SBuf sb;      /* String buffer for tokens. */
  lua_Reader rfunc; /* Reader callback. */
  void *rdata;      /* Reader callback data. */
  BCLine linenumber;    /* Input line counter. */
  BCLine lastline;  /* Line of last token. */
  GCstr *chunkname; /* Current chunk name (interned string). */
  const char *chunkarg; /* Chunk name argument. */
  const char *mode; /* Allow loading bytecode (b) and/or source text (t). */
  VarInfo *vstack;  /* Stack for names and extents of local variables. */
  MSize sizevstack; /* Size of variable stack. */
  MSize vtop;       /* Top of variable stack. */
  BCInsLine *bcstack;   /* Stack for bytecode instructions/line numbers. */
  MSize sizebcstack;    /* Size of bytecode stack. */
  uint32_t level;   /* Syntactical nesting level. */
} LexState;

LJ_FUNC int lj_lex_setup(lua_State *L, LexState *ls);
LJ_FUNC void lj_lex_cleanup(lua_State *L, LexState *ls);
LJ_FUNC void lj_lex_next(LexState *ls);
LJ_FUNC LexToken lj_lex_lookahead(LexState *ls);
LJ_FUNC const char *lj_lex_token2str(LexState *ls, LexToken token);
LJ_FUNC_NORET void lj_lex_error(LexState *ls, LexToken token, ErrMsg em, ...);
LJ_FUNC void lj_lex_init(lua_State *L);

#endif