text:
/*
** $Id: lvm.c,v 2.155.1.1 2013/04/12 18:48:47 roberto Exp $
** Lua virtual machine
** See Copyright Notice in lua.h
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define lvm_c
#define LUA_CORE

#include "lua.h"

#include "ldebug.h"
#include "ldo.h"
#include "lfunc.h"
#include "lgc.h"
#include "lobject.h"
#include "lopcodes.h"
#include "lstate.h"
#include "lstring.h"
#include "ltable.h"
#include "ltm.h"
#include "lvm.h"

/* limit for table tag-method chains (to avoid loops) */
#define MAXTAGLOOP	100

const TValue *luaV_tonumber (const TValue *obj, TValue *n) {
  lua_Number num;
  if (ttisnumber(obj)) return obj;
  if (ttisstring(obj) && luaO_str2d(svalue(obj), tsvalue(obj)->len, &num)) {
    setnvalue(n, num);
    return n;
  }
  else
    return NULL;
}

int luaV_tostring (lua_State *L, StkId obj) {
  if (!ttisnumber(obj))
    return 0;
  else {
    char s[LUAI_MAXNUMBER2STR];
    lua_Number n = nvalue(obj);
    int l = lua_number2str(s, n);
    setsvalue2s(L, obj, luaS_newlstr(L, s, l));
    return 1;
  }
}

static void traceexec (lua_State *L) {
  CallInfo *ci = L->ci;
  lu_byte mask = L->hookmask;
  int counthook = ((mask & LUA_MASKCOUNT) && L->hookcount == 0);
  if (counthook)
    resethookcount(L);  /* reset count */
  if (ci->callstatus & CIST_HOOKYIELD) {  /* called hook last time? */
    ci->callstatus &= ~CIST_HOOKYIELD;  /* erase mark */
    return;  /* do not call hook again (VM yielded, so it did not move) */
  }
  if (counthook)
    luaD_hook(L, LUA_HOOKCOUNT, -1);  /* call count hook */
  if (mask & LUA_MASKLINE) {
    Proto *p = ci_func(ci)->p;
    int npc = pcRel(ci->u.l.savedpc, p);
    int newline = getfuncline(p, npc);
    if (npc == 0 ||  /* call linehook when enter a new function, */
        ci->u.l.savedpc <= L->oldpc ||  /* when jump back (loop), or when */
        newline != getfuncline(p, pcRel(L->oldpc, p)))  /* enter a new line */
      luaD_hook(L, LUA_HOOKLINE, newline);  /* call line hook */
  }
  L->oldpc = ci->u.l.savedpc;
  if (L->status == LUA_YIELD) {  /* did hook yield? */
    if (counthook)
      L->hookcount = 1;  /* undo decrement to zero */
    ci->u.l.savedpc--;  /* undo increment (resume will increment it again) */
    ci->callstatus |= CIST_HOOKYIELD;  /* mark that it yielded */
    ci->func = L->top - 1;  /* protect stack below results */
    luaD_throw(L, LUA_YIELD);
  }
}

static void callTM (lua_State *L, const TValue *f, const TValue *p1,
                    const TValue *p2, TValue *p3, int hasres) {
  ptrdiff_t result = savestack(L, p3);
  setobj2s(L, L->top++, f);  /* push function */
  setobj2s(L, L->top++, p1);  /* 1st argument */
  setobj2s(L, L->top++, p2);  /* 2nd argument */
  if (!hasres)  /* no result? 'p3' is third argument */
    setobj2s(L, L->top++, p3);  /* 3rd argument */
  /* metamethod may yield only when called from Lua code */
  luaD_call(L, L->top - (4 - hasres), hasres, isLua(L->ci));
  if (hasres) {  /* if has result, move it to its place */
    p3 = restorestack(L, result);
    setobjs2s(L, p3, --L->top);
  }
}

void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) {
  int loop;
  for (loop = 0; loop < MAXTAGLOOP; loop++) {
    const TValue *tm;
    if (ttistable(t)) {  /* `t' is a table? */
      Table *h = hvalue(t);
      const TValue *res = luaH_get(h, key); /* do a primitive get */
      if (!ttisnil(res) ||  /* result is not nil? */
          (tm = fasttm(L, h->metatable, TM_INDEX)) == NULL) { /* or no TM? */
        setobj2s(L, val, res);
        return;
      }
      /* else will try the tag method */
    }
    else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_INDEX)))
      luaG_typeerror(L, t, "index");
    if (ttisfunction(tm)) {
      callTM(L, tm, t, key, val, 1);
      return;
    }
    t = tm;  /* else repeat with 'tm' */
  }
  luaG_runerror(L, "loop in gettable");
}

void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
  int loop;
  for (loop = 0; loop < MAXTAGLOOP; loop++) {
    const TValue *tm;
    if (ttistable(t)) {  /* `t' is a table? */
      Table *h = hvalue(t);
      TValue *oldval = cast(TValue *, luaH_get(h, key));
      /* if previous value is not nil, there must be a previous entry
         in the table; moreover, a metamethod has no relevance */
      if (!ttisnil(oldval) ||
         /* previous value is nil; must check the metamethod */
         ((tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL &&
         /* no metamethod; is there a previous entry in the table? */
         (oldval != luaO_nilobject ||
         /* no previous entry; must create one. (The next test is
            always true; we only need the assignment.) */
         (oldval = luaH_newkey(L, h, key), 1)))) {
        /* no metamethod and (now) there is an entry with given key */
        setobj2t(L, oldval, val);  /* assign new value to that entry */
        invalidateTMcache(h);
        luaC_barrierback(L, obj2gco(h), val);
        return;
      }
      /* else will try the metamethod */
    }
    else  /* not a table; check metamethod */
      if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
        luaG_typeerror(L, t, "index");
    /* there is a metamethod */
    if (ttisfunction(tm)) {
      callTM(L, tm, t, key, val, 0);
      return;
    }
    t = tm;  /* else repeat with 'tm' */
  }
  luaG_runerror(L, "loop in settable");
}

static int call_binTM (lua_State *L, const TValue *p1, const TValue *p2,
                       StkId res, TMS event) {
  const TValue *tm = luaT_gettmbyobj(L, p1, event);  /* try first operand */
  if (ttisnil(tm))
    tm = luaT_gettmbyobj(L, p2, event);  /* try second operand */
  if (ttisnil(tm)) return 0;
  callTM(L, tm, p1, p2, res, 1);
  return 1;
}

static const TValue *get_equalTM (lua_State *L, Table *mt1, Table *mt2,
                                  TMS event) {
  const TValue *tm1 = fasttm(L, mt1, event);
  const TValue *tm2;
  if (tm1 == NULL) return NULL;  /* no metamethod */
  if (mt1 == mt2) return tm1;  /* same metatables => same metamethods */
  tm2 = fasttm(L, mt2, event);
  if (tm2 == NULL) return NULL;  /* no metamethod */
  if (luaV_rawequalobj(tm1, tm2))  /* same metamethods? */
    return tm1;
  return NULL;
}

static int call_orderTM (lua_State *L, const TValue *p1, const TValue *p2,
                         TMS event) {
  if (!call_binTM(L, p1, p2, L->top, event))
    return -1;  /* no metamethod */
  else
    return !l_isfalse(L->top);
}

static int l_strcmp (const TString *ls, const TString *rs) {
  const char *l = getstr(ls);
  size_t ll = ls->tsv.len;
  const char *r = getstr(rs);
  size_t lr = rs->tsv.len;
  for (;;) {
    int temp = strcoll(l, r);
    if (temp != 0) return temp;
    else {  /* strings are equal up to a `\0' */
      size_t len = strlen(l);  /* index of first `\0' in both strings */
      if (len == lr)  /* r is finished? */
        return (len == ll) ? 0 : 1;
      else if (len == ll)  /* l is finished? */
        return -1;  /* l is smaller than r (because r is not finished) */
      /* both strings longer than `len'; go on comparing (after the `\0') */
      len++;
      l += len; ll -= len; r += len; lr -= len;
    }
  }
}

int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) {
  int res;
  if (ttisnumber(l) && ttisnumber(r))
    return luai_numlt(L, nvalue(l), nvalue(r));
  else if (ttisstring(l) && ttisstring(r))
    return l_strcmp(rawtsvalue(l), rawtsvalue(r)) < 0;
  else if ((res = call_orderTM(L, l, r, TM_LT)) < 0)
    luaG_ordererror(L, l, r);
  return res;
}

int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) {
  int res;
  if (ttisnumber(l) && ttisnumber(r))
    return luai_numle(L, nvalue(l), nvalue(r));
  else if (ttisstring(l) && ttisstring(r))
    return l_strcmp(rawtsvalue(l), rawtsvalue(r)) <= 0;
  else if ((res = call_orderTM(L, l, r, TM_LE)) >= 0)  /* first try `le' */
    return res;
  else if ((res = call_orderTM(L, r, l, TM_LT)) < 0)  /* else try `lt' */
    luaG_ordererror(L, l, r);
  return !res;
}

/*
** equality of Lua values. L == NULL means raw equality (no metamethods)
*/
int luaV_equalobj_ (lua_State *L, const TValue *t1, const TValue *t2) {
  const TValue *tm;
  lua_assert(ttisequal(t1, t2));
  switch (ttype(t1)) {
    case LUA_TNIL: return 1;
    case LUA_TNUMBER: return luai_numeq(nvalue(t1), nvalue(t2));
    case LUA_TBOOLEAN: return bvalue(t1) == bvalue(t2);  /* true must be 1 !! */
    case LUA_TLIGHTUSERDATA: return pvalue(t1) == pvalue(t2);
    case LUA_TLCF: return fvalue(t1) == fvalue(t2);
    case LUA_TSHRSTR: return eqshrstr(rawtsvalue(t1), rawtsvalue(t2));
    case LUA_TLNGSTR: return luaS_eqlngstr(rawtsvalue(t1), rawtsvalue(t2));
    case LUA_TUSERDATA: {
      if (uvalue(t1) == uvalue(t2)) return 1;
      else if (L == NULL) return 0;
      tm = get_equalTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable, TM_EQ);
      break;  /* will try TM */
    }
    case LUA_TTABLE: {
      if (hvalue(t1) == hvalue(t2)) return 1;
      else if (L == NULL) return 0;
      tm = get_equalTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ);
      break;  /* will try TM */
    }
    default:
      lua_assert(iscollectable(t1));
      return gcvalue(t1) == gcvalue(t2);
  }
  if (tm == NULL) return 0;  /* no TM? */
  callTM(L, tm, t1, t2, L->top, 1);  /* call TM */
  return !l_isfalse(L->top);
}

void luaV_concat (lua_State *L, int total) {
  lua_assert(total >= 2);
  do {
    StkId top = L->top;
    int n = 2;  /* number of elements handled in this pass (at least 2) */
    if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) {
      if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT))
        luaG_concaterror(L, top-2, top-1);
    }
    else if (tsvalue(top-1)->len == 0)  /* second operand is empty? */
      (void)tostring(L, top - 2);  /* result is first operand */
    else if (ttisstring(top-2) && tsvalue(top-2)->len == 0) {
      setobjs2s(L, top - 2, top - 1);  /* result is second op. */
    }
    else {
      /* at least two non-empty string values; get as many as possible */
      size_t tl = tsvalue(top-1)->len;
      char *buffer;
      int i;
      /* collect total length */
      for (i = 1; i < total && tostring(L, top-i-1); i++) {
        size_t l = tsvalue(top-i-1)->len;
        if (l >= (MAX_SIZET/sizeof(char)) - tl)
          luaG_runerror(L, "string length overflow");
        tl += l;
      }
      buffer = luaZ_openspace(L, &G(L)->buff, tl);
      tl = 0;
      n = i;
      do {  /* concat all strings */
        size_t l = tsvalue(top-i)->len;
        memcpy(buffer+tl, svalue(top-i), l * sizeof(char));
        tl += l;
      } while (--i > 0);
      setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl));
    }
    total -= n-1;  /* got 'n' strings to create 1 new */
    L->top -= n-1;  /* popped 'n' strings and pushed one */
  } while (total > 1);  /* repeat until only 1 result left */
}

void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) {
  const TValue *tm;
  switch (ttypenv(rb)) {
    case LUA_TTABLE: {
      Table *h = hvalue(rb);
      tm = fasttm(L, h->metatable, TM_LEN);
      if (tm) break;  /* metamethod? break switch to call it */
      setnvalue(ra, cast_num(luaH_getn(h)));  /* else primitive len */
      return;
    }
    case LUA_TSTRING: {
      setnvalue(ra, cast_num(tsvalue(rb)->len));
      return;
    }
    default: {  /* try metamethod */
      tm = luaT_gettmbyobj(L, rb, TM_LEN);
      if (ttisnil(tm))  /* no metamethod? */
        luaG_typeerror(L, rb, "get length of");
      break;
    }
  }
  callTM(L, tm, rb, rb, ra, 1);
}

void luaV_arith (lua_State *L, StkId ra, const TValue *rb,
                 const TValue *rc, TMS op) {
  TValue tempb, tempc;
  const TValue *b, *c;
  if ((b = luaV_tonumber(rb, &tempb)) != NULL &&
      (c = luaV_tonumber(rc, &tempc)) != NULL) {
    lua_Number res = luaO_arith(op - TM_ADD + LUA_OPADD, nvalue(b), nvalue(c));
    setnvalue(ra, res);
  }
  else if (!call_binTM(L, rb, rc, ra, op))
    luaG_aritherror(L, rb, rc);
}

/*
** check whether cached closure in prototype 'p' may be reused, that is,
** whether there is a cached closure with the same upvalues needed by
** new closure to be created.
*/
static Closure *getcached (Proto *p, UpVal **encup, StkId base) {
  Closure *c = p->cache;
  if (c != NULL) {  /* is there a cached closure? */
    int nup = p->sizeupvalues;
    Upvaldesc *uv = p->upvalues;
    int i;
    for (i = 0; i < nup; i++) {  /* check whether it has right upvalues */
      TValue *v = uv[i].instack ? base + uv[i].idx : encup[uv[i].idx]->v;
      if (c->l.upvals[i]->v != v)
        return NULL;  /* wrong upvalue; cannot reuse closure */
    }
  }
  return c;  /* return cached closure (or NULL if no cached closure) */
}

/*
** create a new Lua closure, push it in the stack, and initialize
** its upvalues. Note that the call to 'luaC_barrierproto' must come
** before the assignment to 'p->cache', as the function needs the
** original value of that field.
*/
static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base,
                         StkId ra) {
  int nup = p->sizeupvalues;
  Upvaldesc *uv = p->upvalues;
  int i;
  Closure *ncl = luaF_newLclosure(L, nup);
  ncl->l.p = p;
  setclLvalue(L, ra, ncl);  /* anchor new closure in stack */
  for (i = 0; i < nup; i++) {  /* fill in its upvalues */
    if (uv[i].instack)  /* upvalue refers to local variable? */
      ncl->l.upvals[i] = luaF_findupval(L, base + uv[i].idx);
    else  /* get upvalue from enclosing function */
      ncl->l.upvals[i] = encup[uv[i].idx];
  }
  luaC_barrierproto(L, p, ncl);
  p->cache = ncl;  /* save it on cache for reuse */
}

/*
** finish execution of an opcode interrupted by an yield
*/
void luaV_finishOp (lua_State *L) {
  CallInfo *ci = L->ci;
  StkId base = ci->u.l.base;
  Instruction inst = *(ci->u.l.savedpc - 1);  /* interrupted instruction */
  OpCode op = GET_OPCODE(inst);
  switch (op) {  /* finish its execution */
    case OP_ADD: case OP_SUB: case OP_MUL: case OP_DIV:
    case OP_MOD: case OP_POW: case OP_UNM: case OP_LEN:
    case OP_GETTABUP: case OP_GETTABLE: case OP_SELF: {
      setobjs2s(L, base + GETARG_A(inst), --L->top);
      break;
    }
    case OP_LE: case OP_LT: case OP_EQ: {
      int res = !l_isfalse(L->top - 1);
      L->top--;
      /* metamethod should not be called when operand is K */
      lua_assert(!ISK(GETARG_B(inst)));
      if (op == OP_LE &&  /* "<=" using "<" instead? */
          ttisnil(luaT_gettmbyobj(L, base + GETARG_B(inst), TM_LE)))
        res = !res;  /* invert result */
      lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP);
      if (res != GETARG_A(inst))  /* condition failed? */
        ci->u.l.savedpc++;  /* skip jump instruction */
      break;
    }
    case OP_CONCAT: {
      StkId top = L->top - 1;  /* top when 'call_binTM' was called */
      int b = GETARG_B(inst);      /* first element to concatenate */
      int total = cast_int(top - 1 - (base + b));  /* yet to concatenate */
      setobj2s(L, top - 2, top);  /* put TM result in proper position */
      if (total > 1) {  /* are there elements to concat? */
        L->top = top - 1;  /* top is one after last element (at top-2) */
        luaV_concat(L, total);  /* concat them (may yield again) */
      }
      /* move final result to final position */
      setobj2s(L, ci->u.l.base + GETARG_A(inst), L->top - 1);
      L->top = ci->top;  /* restore top */
      break;
    }
    case OP_TFORCALL: {
      lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_TFORLOOP);
      L->top = ci->top;  /* correct top */
      break;
    }
    case OP_CALL: {
      if (GETARG_C(inst) - 1 >= 0)  /* nresults >= 0? */
        L->top = ci->top;  /* adjust results */
      break;
    }
    case OP_TAILCALL: case OP_SETTABUP: case OP_SETTABLE:
      break;
    default: lua_assert(0);
  }
}

/*
** some macros for common tasks in `luaV_execute'
*/

#if !defined luai_runtimecheck
#define luai_runtimecheck(L, c)		/* void */
#endif

#define RA(i)	(base+GETARG_A(i))
/* to be used after possible stack reallocation */
#define RB(i)	check_exp(getBMode(GET_OPCODE(i)) == OpArgR, base+GETARG_B(i))
#define RC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgR, base+GETARG_C(i))
#define RKB(i)	check_exp(getBMode(GET_OPCODE(i)) == OpArgK, \
	ISK(GETARG_B(i)) ? k+INDEXK(GETARG_B(i)) : base+GETARG_B(i))
#define RKC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \
	ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i))
#define KBx(i)  \
  (k + (GETARG_Bx(i) != 0 ? GETARG_Bx(i) - 1 : GETARG_Ax(*ci->u.l.savedpc++)))

/* execute a jump instruction */
#define dojump(ci,i,e) \
  { int a = GETARG_A(i); \
    if (a > 0) luaF_close(L, ci->u.l.base + a - 1); \
    ci->u.l.savedpc += GETARG_sBx(i) + e; }

/* for test instructions, execute the jump instruction that follows it */
#define donextjump(ci)	{ i = *ci->u.l.savedpc; dojump(ci, i, 1); }

#define Protect(x)	{ {x;}; base = ci->u.l.base; }

#define checkGC(L,c)  \
  Protect( luaC_condGC(L,{L->top = (c);  /* limit of live values */ \
                          luaC_step(L); \
                          L->top = ci->top;})  /* restore top */ \
           luai_threadyield(L); )

#define arith_op(op,tm) { \
        TValue *rb = RKB(i); \
        TValue *rc = RKC(i); \
        if (ttisnumber(rb) && ttisnumber(rc)) { \
          lua_Number nb = nvalue(rb), nc = nvalue(rc); \
          setnvalue(ra, op(L, nb, nc)); \
        } \
        else { Protect(luaV_arith(L, ra, rb, rc, tm)); } }

#define vmdispatch(o)	switch(o)
#define vmcase(l,b)	case l: {b}  break;
#define vmcasenb(l,b)	case l: {b}		/* nb = no break */

void luaV_execute (lua_State *L) {
  CallInfo *ci = L->ci;
  LClosure *cl;
  TValue *k;
  StkId base;
 newframe:  /* reentry point when frame changes (call/return) */
  lua_assert(ci == L->ci);
  cl = clLvalue(ci->func);
  k = cl->p->k;
  base = ci->u.l.base;
  /* main loop of interpreter */
  for (;;) {
    Instruction i = *(ci->u.l.savedpc++);
    StkId ra;
    if ((L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) &&
        (--L->hookcount == 0 || L->hookmask & LUA_MASKLINE)) {
      Protect(traceexec(L));
    }
    /* WARNING: several calls may realloc the stack and invalidate `ra' */
    ra = RA(i);
    lua_assert(base == ci->u.l.base);
    lua_assert(base <= L->top && L->top < L->stack + L->stacksize);
    vmdispatch (GET_OPCODE(i)) {
      vmcase(OP_MOVE,
        setobjs2s(L, ra, RB(i));
      )
      vmcase(OP_LOADK,
        TValue *rb = k + GETARG_Bx(i);
        setobj2s(L, ra, rb);
      )
      vmcase(OP_LOADKX,
        TValue *rb;
        lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG);
        rb = k + GETARG_Ax(*ci->u.l.savedpc++);
        setobj2s(L, ra, rb);
      )
      vmcase(OP_LOADBOOL,
        setbvalue(ra, GETARG_B(i));
        if (GETARG_C(i)) ci->u.l.savedpc++;  /* skip next instruction (if C) */
      )
      vmcase(OP_LOADNIL,
        int b = GETARG_B(i);
        do {
          setnilvalue(ra++);
        } while (b--);
      )
      vmcase(OP_GETUPVAL,
        int b = GETARG_B(i);
        setobj2s(L, ra, cl->upvals[b]->v);
      )
      vmcase(OP_GETTABUP,
        int b = GETARG_B(i);
        Protect(luaV_gettable(L, cl->upvals[b]->v, RKC(i), ra));
      )
      vmcase(OP_GETTABLE,
        Protect(luaV_gettable(L, RB(i), RKC(i), ra));
      )
      vmcase(OP_SETTABUP,
        int a = GETARG_A(i);
        Protect(luaV_settable(L, cl->upvals[a]->v, RKB(i), RKC(i)));
      )
      vmcase(OP_SETUPVAL,
        UpVal *uv = cl->upvals[GETARG_B(i)];
        setobj(L, uv->v, ra);
        luaC_barrier(L, uv, ra);
      )
      vmcase(OP_SETTABLE,
        Protect(luaV_settable(L, ra, RKB(i), RKC(i)));
      )
      vmcase(OP_NEWTABLE,
        int b = GETARG_B(i);
        int c = GETARG_C(i);
        Table *t = luaH_new(L);
        sethvalue(L, ra, t);
        if (b != 0 || c != 0)
          luaH_resize(L, t, luaO_fb2int(b), luaO_fb2int(c));
        checkGC(L, ra + 1);
      )
      vmcase(OP_SELF,
        StkId rb = RB(i);
        setobjs2s(L, ra+1, rb);
        Protect(luaV_gettable(L, rb, RKC(i), ra));
      )
      vmcase(OP_ADD,
        arith_op(luai_numadd, TM_ADD);
      )
      vmcase(OP_SUB,
        arith_op(luai_numsub, TM_SUB);
      )
      vmcase(OP_MUL,
        arith_op(luai_nummul, TM_MUL);
      )
      vmcase(OP_DIV,
        arith_op(luai_numdiv, TM_DIV);
      )
      vmcase(OP_MOD,
        arith_op(luai_nummod, TM_MOD);
      )
      vmcase(OP_POW,
        arith_op(luai_numpow, TM_POW);
      )
      vmcase(OP_UNM,
        TValue *rb = RB(i);
        if (ttisnumber(rb)) {
          lua_Number nb = nvalue(rb);
          setnvalue(ra, luai_numunm(L, nb));
        }
        else {
          Protect(luaV_arith(L, ra, rb, rb, TM_UNM));
        }
      )
      vmcase(OP_NOT,
        TValue *rb = RB(i);
        int res = l_isfalse(rb);  /* next assignment may change this value */
        setbvalue(ra, res);
      )
      vmcase(OP_LEN,
        Protect(luaV_objlen(L, ra, RB(i)));
      )
      vmcase(OP_CONCAT,
        int b = GETARG_B(i);
        int c = GETARG_C(i);
        StkId rb;
        L->top = base + c + 1;  /* mark the end of concat operands */
        Protect(luaV_concat(L, c - b + 1));
        ra = RA(i);  /* 'luav_concat' may invoke TMs and move the stack */
        rb = b + base;
        setobjs2s(L, ra, rb);
        checkGC(L, (ra >= rb ? ra + 1 : rb));
        L->top = ci->top;  /* restore top */
      )
      vmcase(OP_JMP,
        dojump(ci, i, 0);
      )
      vmcase(OP_EQ,
        TValue *rb = RKB(i);
        TValue *rc = RKC(i);
        Protect(
          if (cast_int(equalobj(L, rb, rc)) != GETARG_A(i))
            ci->u.l.savedpc++;
          else
            donextjump(ci);
        )
      )
      vmcase(OP_LT,
        Protect(
          if (luaV_lessthan(L, RKB(i), RKC(i)) != GETARG_A(i))
            ci->u.l.savedpc++;
          else
            donextjump(ci);
        )
      )
      vmcase(OP_LE,
        Protect(
          if (luaV_lessequal(L, RKB(i), RKC(i)) != GETARG_A(i))
            ci->u.l.savedpc++;
          else
            donextjump(ci);
        )
      )
      vmcase(OP_TEST,
        if (GETARG_C(i) ? l_isfalse(ra) : !l_isfalse(ra))
            ci->u.l.savedpc++;
          else
          donextjump(ci);
      )
      vmcase(OP_TESTSET,
        TValue *rb = RB(i);
        if (GETARG_C(i) ? l_isfalse(rb) : !l_isfalse(rb))
          ci->u.l.savedpc++;
        else {
          setobjs2s(L, ra, rb);
          donextjump(ci);
        }
      )
      vmcase(OP_CALL,
        int b = GETARG_B(i);
        int nresults = GETARG_C(i) - 1;
        if (b != 0) L->top = ra+b;  /* else previous instruction set top */
        if (luaD_precall(L, ra, nresults)) {  /* C function? */
          if (nresults >= 0) L->top = ci->top;  /* adjust results */
          base = ci->u.l.base;
        }
        else {  /* Lua function */
          ci = L->ci;
          ci->callstatus |= CIST_REENTRY;
          goto newframe;  /* restart luaV_execute over new Lua function */
        }
      )
      vmcase(OP_TAILCALL,
        int b = GETARG_B(i);
        if (b != 0) L->top = ra+b;  /* else previous instruction set top */
        lua_assert(GETARG_C(i) - 1 == LUA_MULTRET);
        if (luaD_precall(L, ra, LUA_MULTRET))  /* C function? */
          base = ci->u.l.base;
        else {
          /* tail call: put called frame (n) in place of caller one (o) */
          CallInfo *nci = L->ci;  /* called frame */
          CallInfo *oci = nci->previous;  /* caller frame */
          StkId nfunc = nci->func;  /* called function */
          StkId ofunc = oci->func;  /* caller function */
          /* last stack slot filled by 'precall' */
          StkId lim = nci->u.l.base + getproto(nfunc)->numparams;
          int aux;
          /* close all upvalues from previous call */
          if (cl->p->sizep > 0) luaF_close(L, oci->u.l.base);
          /* move new frame into old one */
          for (aux = 0; nfunc + aux < lim; aux++)
            setobjs2s(L, ofunc + aux, nfunc + aux);
          oci->u.l.base = ofunc + (nci->u.l.base - nfunc);  /* correct base */
          oci->top = L->top = ofunc + (L->top - nfunc);  /* correct top */
          oci->u.l.savedpc = nci->u.l.savedpc;
          oci->callstatus |= CIST_TAIL;  /* function was tail called */
          ci = L->ci = oci;  /* remove new frame */
          lua_assert(L->top == oci->u.l.base + getproto(ofunc)->maxstacksize);
          goto newframe;  /* restart luaV_execute over new Lua function */
        }
      )
      vmcasenb(OP_RETURN,
        int b = GETARG_B(i);
        if (b != 0) L->top = ra+b-1;
        if (cl->p->sizep > 0) luaF_close(L, base);
        b = luaD_poscall(L, ra);
        if (!(ci->callstatus & CIST_REENTRY))  /* 'ci' still the called one */
          return;  /* external invocation: return */
        else {  /* invocation via reentry: continue execution */
          ci = L->ci;
          if (b) L->top = ci->top;
          lua_assert(isLua(ci));
          lua_assert(GET_OPCODE(*((ci)->u.l.savedpc - 1)) == OP_CALL);
          goto newframe;  /* restart luaV_execute over new Lua function */
        }
      )
      vmcase(OP_FORLOOP,
        lua_Number step = nvalue(ra+2);
        lua_Number idx = luai_numadd(L, nvalue(ra), step); /* increment index */
        lua_Number limit = nvalue(ra+1);
        if (luai_numlt(L, 0, step) ? luai_numle(L, idx, limit)
                                   : luai_numle(L, limit, idx)) {
          ci->u.l.savedpc += GETARG_sBx(i);  /* jump back */
          setnvalue(ra, idx);  /* update internal index... */
          setnvalue(ra+3, idx);  /* ...and external index */
        }
      )
      vmcase(OP_FORPREP,
        const TValue *init = ra;
        const TValue *plimit = ra+1;
        const TValue *pstep = ra+2;
        if (!tonumber(init, ra))
          luaG_runerror(L, LUA_QL("for") " initial value must be a number");
        else if (!tonumber(plimit, ra+1))
          luaG_runerror(L, LUA_QL("for") " limit must be a number");
        else if (!tonumber(pstep, ra+2))
          luaG_runerror(L, LUA_QL("for") " step must be a number");
        setnvalue(ra, luai_numsub(L, nvalue(ra), nvalue(pstep)));
        ci->u.l.savedpc += GETARG_sBx(i);
      )
      vmcasenb(OP_TFORCALL,
        StkId cb = ra + 3;  /* call base */
        setobjs2s(L, cb+2, ra+2);
        setobjs2s(L, cb+1, ra+1);
        setobjs2s(L, cb, ra);
        L->top = cb + 3;  /* func. + 2 args (state and index) */
        Protect(luaD_call(L, cb, GETARG_C(i), 1));
        L->top = ci->top;
        i = *(ci->u.l.savedpc++);  /* go to next instruction */
        ra = RA(i);
        lua_assert(GET_OPCODE(i) == OP_TFORLOOP);
        goto l_tforloop;
      )
      vmcase(OP_TFORLOOP,
        l_tforloop:
        if (!ttisnil(ra + 1)) {  /* continue loop? */
          setobjs2s(L, ra, ra + 1);  /* save control variable */
           ci->u.l.savedpc += GETARG_sBx(i);  /* jump back */
        }
      )
      vmcase(OP_SETLIST,
        int n = GETARG_B(i);
        int c = GETARG_C(i);
        int last;
        Table *h;
        if (n == 0) n = cast_int(L->top - ra) - 1;
        if (c == 0) {
          lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG);
          c = GETARG_Ax(*ci->u.l.savedpc++);
        }
        luai_runtimecheck(L, ttistable(ra));
        h = hvalue(ra);
        last = ((c-1)*LFIELDS_PER_FLUSH) + n;
        if (last > h->sizearray)  /* needs more space? */
          luaH_resizearray(L, h, last);  /* pre-allocate it at once */
        for (; n > 0; n--) {
          TValue *val = ra+n;
          luaH_setint(L, h, last--, val);
          luaC_barrierback(L, obj2gco(h), val);
        }
        L->top = ci->top;  /* correct top (in case of previous open call) */
      )
      vmcase(OP_CLOSURE,
        Proto *p = cl->p->p[GETARG_Bx(i)];
        Closure *ncl = getcached(p, cl->upvals, base);  /* cached closure */
        if (ncl == NULL)  /* no match? */
          pushclosure(L, p, cl->upvals, base, ra);  /* create a new one */
        else
          setclLvalue(L, ra, ncl);  /* push cashed closure */
        checkGC(L, ra + 1);
      )
      vmcase(OP_VARARG,
        int b = GETARG_B(i) - 1;
        int j;
        int n = cast_int(base - ci->func) - cl->p->numparams - 1;
        if (b < 0) {  /* B == 0? */
          b = n;  /* get all var. arguments */
          Protect(luaD_checkstack(L, n));
          ra = RA(i);  /* previous call may change the stack */
          L->top = ra + n;
        }
        for (j = 0; j < b; j++) {
          if (j < n) {
            setobjs2s(L, ra + j, base - n + j);
          }
          else {
            setnilvalue(ra + j);
          }
        }
      )
      vmcase(OP_EXTRAARG,
        lua_assert(0);
      )
    }
  }
}


text:
/*
** $Id: llex.h,v 1.72.1.1 2013/04/12 18:48:47 roberto Exp $
** Lexical Analyzer
** See Copyright Notice in lua.h
*/

#ifndef llex_h
#define llex_h

#include "lobject.h"
#include "lzio.h"

#define FIRST_RESERVED	257

/*
* WARNING: if you change the order of this enumeration,
* grep "ORDER RESERVED"
*/
enum RESERVED {
  /* terminal symbols denoted by reserved words */
  TK_AND = FIRST_RESERVED, TK_BREAK,
  TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,
  TK_GOTO, TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
  TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,
  /* other terminal symbols */
  TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE, TK_DBCOLON, TK_EOS,
  TK_NUMBER, TK_NAME, TK_STRING
};

/* number of reserved words */
#define NUM_RESERVED	(cast(int, TK_WHILE-FIRST_RESERVED+1))

typedef union {
  lua_Number r;
  TString *ts;
} SemInfo;  /* semantics information */

typedef struct Token {
  int token;
  SemInfo seminfo;
} Token;

/* state of the lexer plus state of the parser when shared by all
   functions */
typedef struct LexState {
  int current;  /* current character (charint) */
  int linenumber;  /* input line counter */
  int lastline;  /* line of last token `consumed' */
  Token t;  /* current token */
  Token lookahead;  /* look ahead token */
  struct FuncState *fs;  /* current function (parser) */
  struct lua_State *L;
  ZIO *z;  /* input stream */
  Mbuffer *buff;  /* buffer for tokens */
  struct Dyndata *dyd;  /* dynamic structures used by the parser */
  TString *source;  /* current source name */
  TString *envn;  /* environment variable name */
  char decpoint;  /* locale decimal point */
} LexState;

LUAI_FUNC void luaX_init (lua_State *L);
LUAI_FUNC void luaX_setinput (lua_State *L, LexState *ls, ZIO *z,
                              TString *source, int firstchar);
LUAI_FUNC TString *luaX_newstring (LexState *ls, const char *str, size_t l);
LUAI_FUNC void luaX_next (LexState *ls);
LUAI_FUNC int luaX_lookahead (LexState *ls);
LUAI_FUNC l_noret luaX_syntaxerror (LexState *ls, const char *s);
LUAI_FUNC const char *luaX_token2str (LexState *ls, int token);

#endif

repo_language: C

mime_type: text/x-c


text:
/*
** $Id: llimits.h,v 1.103.1.1 2013/04/12 18:48:47 roberto Exp $
** Limits, basic types, and some other `installation-dependent' definitions
** See Copyright Notice in lua.h
*/

#ifndef llimits_h
#define llimits_h

#include <limits.h>
#include <stddef.h>

#include "lua.h"

typedef unsigned LUA_INT32 lu_int32;

typedef LUAI_UMEM lu_mem;

typedef LUAI_MEM l_mem;

/* chars used as small naturals (so that `char' is reserved for characters) */
typedef unsigned char lu_byte;

#define MAX_SIZET	((size_t)(~(size_t)0)-2)

#define MAX_LUMEM	((lu_mem)(~(lu_mem)0)-2)

#define MAX_LMEM	((l_mem) ((MAX_LUMEM >> 1) - 2))

#define MAX_INT (INT_MAX-2)  /* maximum value of an int (-2 for safety) */

/*
** conversion of pointer to integer
** this is for hashing only; there is no problem if the integer
** cannot hold the whole pointer value
*/
#define IntPoint(p)  ((unsigned int)(lu_mem)(p))

/* type to ensure maximum alignment */
#if !defined(LUAI_USER_ALIGNMENT_T)
#define LUAI_USER_ALIGNMENT_T	union { double u; void *s; long l; }
#endif

typedef LUAI_USER_ALIGNMENT_T L_Umaxalign;

/* result of a `usual argument conversion' over lua_Number */
typedef LUAI_UACNUMBER l_uacNumber;

/* internal assertions for in-house debugging */
#if defined(lua_assert)
#define check_exp(c,e)		(lua_assert(c), (e))
/* to avoid problems with conditions too long */
#define lua_longassert(c)	{ if (!(c)) lua_assert(0); }
#else
#define lua_assert(c)		((void)0)
#define check_exp(c,e)		(e)
#define lua_longassert(c)	((void)0)
#endif

/*
** assertion for checking API calls
*/
#if !defined(luai_apicheck)

#if defined(LUA_USE_APICHECK)
#include <assert.h>
#define luai_apicheck(L,e)	assert(e)
#else
#define luai_apicheck(L,e)	lua_assert(e)
#endif

#endif

#define api_check(l,e,msg)	luai_apicheck(l,(e) && msg)

#if !defined(UNUSED)
#define UNUSED(x)	((void)(x))	/* to avoid warnings */
#endif

#define cast(t, exp)	((t)(exp))

#define cast_byte(i)	cast(lu_byte, (i))
#define cast_num(i)	cast(lua_Number, (i))
#define cast_int(i)	cast(int, (i))
#define cast_uchar(i)	cast(unsigned char, (i))

/*
** non-return type
*/
#if defined(__GNUC__)
#define l_noret		void __attribute__((noreturn))
#elif defined(_MSC_VER)
#define l_noret		void __declspec(noreturn)
#else
#define l_noret		void
#endif

/*
** maximum depth for nested C calls and syntactical nested non-terminals
** in a program. (Value must fit in an unsigned short int.)
*/
#if !defined(LUAI_MAXCCALLS)
#define LUAI_MAXCCALLS		200
#endif

/*
** maximum number of upvalues in a closure (both C and Lua). (Value
** must fit in an unsigned char.)
*/
#define MAXUPVAL	UCHAR_MAX

/*
** type for virtual-machine instructions
** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
*/
typedef lu_int32 Instruction;

/* maximum stack for a Lua function */
#define MAXSTACK	250

/* minimum size for the string table (must be power of 2) */
#if !defined(MINSTRTABSIZE)
#define MINSTRTABSIZE	32
#endif

/* minimum size for string buffer */
#if !defined(LUA_MINBUFFER)
#define LUA_MINBUFFER	32
#endif

#if !defined(lua_lock)
#define lua_lock(L)     ((void) 0)
#define lua_unlock(L)   ((void) 0)
#endif

#if !defined(luai_threadyield)
#define luai_threadyield(L)     {lua_unlock(L); lua_lock(L);}
#endif

/*
** these macros allow user-specific actions on threads when you defined
** LUAI_EXTRASPACE and need to do something extra when a thread is
** created/deleted/resumed/yielded.
*/
#if !defined(luai_userstateopen)
#define luai_userstateopen(L)		((void)L)
#endif

#if !defined(luai_userstateclose)
#define luai_userstateclose(L)		((void)L)
#endif

#if !defined(luai_userstatethread)
#define luai_userstatethread(L,L1)	((void)L)
#endif

#if !defined(luai_userstatefree)
#define luai_userstatefree(L,L1)	((void)L)
#endif

#if !defined(luai_userstateresume)
#define luai_userstateresume(L,n)       ((void)L)
#endif

#if !defined(luai_userstateyield)
#define luai_userstateyield(L,n)        ((void)L)
#endif

/*
** lua_number2int is a macro to convert lua_Number to int.
** lua_number2integer is a macro to convert lua_Number to lua_Integer.
** lua_number2unsigned is a macro to convert a lua_Number to a lua_Unsigned.
** lua_unsigned2number is a macro to convert a lua_Unsigned to a lua_Number.
** luai_hashnum is a macro to hash a lua_Number value into an integer.
** The hash must be deterministic and give reasonable values for
** both small and large values (outside the range of integers).
*/

#if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK)	/* { */
/* trick with Microsoft assembler for X86 */

#define lua_number2int(i,n)  __asm {__asm fld n   __asm fistp i}
#define lua_number2integer(i,n)		lua_number2int(i, n)
#define lua_number2unsigned(i,n)  \
  {__int64 l; __asm {__asm fld n   __asm fistp l} i = (unsigned int)l;}

#elif defined(LUA_IEEE754TRICK)		/* }{ */
/* the next trick should work on any machine using IEEE754 with
   a 32-bit int type */

union luai_Cast { double l_d; LUA_INT32 l_p[2]; };

#if !defined(LUA_IEEEENDIAN)	/* { */
#define LUAI_EXTRAIEEE	\
  static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)};
#define LUA_IEEEENDIANLOC	(ieeeendian.l_p[1] == 33)
#else
#define LUA_IEEEENDIANLOC	LUA_IEEEENDIAN
#define LUAI_EXTRAIEEE		/* empty */
#endif				/* } */

#define lua_number2int32(i,n,t) \
  { LUAI_EXTRAIEEE \
    volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \
    (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; }

#define luai_hashnum(i,n)  \
  { volatile union luai_Cast u; u.l_d = (n) + 1.0;  /* avoid -0 */ \
    (i) = u.l_p[0]; (i) += u.l_p[1]; }  /* add double bits for his hash */

#define lua_number2int(i,n)		lua_number2int32(i, n, int)
#define lua_number2unsigned(i,n)	lua_number2int32(i, n, lua_Unsigned)

/* the trick can be expanded to lua_Integer when it is a 32-bit value */
#if defined(LUA_IEEELL)
#define lua_number2integer(i,n)		lua_number2int32(i, n, lua_Integer)
#endif

#endif				/* } */

/* the following definitions always work, but may be slow */

#if !defined(lua_number2int)
#define lua_number2int(i,n)	((i)=(int)(n))
#endif

#if !defined(lua_number2integer)
#define lua_number2integer(i,n)	((i)=(lua_Integer)(n))
#endif

#if !defined(lua_number2unsigned)	/* { */
/* the following definition assures proper modulo behavior */
#if defined(LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_FLOAT)
#include <math.h>
#define SUPUNSIGNED	((lua_Number)(~(lua_Unsigned)0) + 1)
#define lua_number2unsigned(i,n)  \
	((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED))
#else
#define lua_number2unsigned(i,n)	((i)=(lua_Unsigned)(n))
#endif
#endif				/* } */

#if !defined(lua_unsigned2number)
/* on several machines, coercion from unsigned to double is slow,
   so it may be worth to avoid */
#define lua_unsigned2number(u)  \
    (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u))
#endif

#if defined(ltable_c) && !defined(luai_hashnum)

#include <float.h>
#include <math.h>

#define luai_hashnum(i,n) { int e;  \
  n = l_mathop(frexp)(n, &e) * (lua_Number)(INT_MAX - DBL_MAX_EXP);  \
  lua_number2int(i, n); i += e; }

#endif

/*
** macro to control inclusion of some hard tests on stack reallocation
*/
#if !defined(HARDSTACKTESTS)
#define condmovestack(L)	((void)0)
#else
/* realloc stack keeping its size */
#define condmovestack(L)	luaD_reallocstack((L), (L)->stacksize)
#endif

#if !defined(HARDMEMTESTS)
#define condchangemem(L)	condmovestack(L)
#else
#define condchangemem(L)  \
	((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1)))
#endif

#endif


text:
/*
** $Id: lbitlib.c,v 1.18.1.2 2013/07/09 18:01:41 roberto Exp $
** Standard library for bitwise operations
** See Copyright Notice in lua.h
*/

#define lbitlib_c
#define LUA_LIB

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"

/* number of bits to consider in a number */
#if !defined(LUA_NBITS)
#define LUA_NBITS	32
#endif

#define ALLONES		(~(((~(lua_Unsigned)0) << (LUA_NBITS - 1)) << 1))

/* macro to trim extra bits */
#define trim(x)		((x) & ALLONES)

/* builds a number with 'n' ones (1 <= n <= LUA_NBITS) */
#define mask(n)		(~((ALLONES << 1) << ((n) - 1)))

typedef lua_Unsigned b_uint;

static b_uint andaux (lua_State *L) {
  int i, n = lua_gettop(L);
  b_uint r = ~(b_uint)0;
  for (i = 1; i <= n; i++)
    r &= luaL_checkunsigned(L, i);
  return trim(r);
}

static int b_and (lua_State *L) {
  b_uint r = andaux(L);
  lua_pushunsigned(L, r);
  return 1;
}

static int b_test (lua_State *L) {
  b_uint r = andaux(L);
  lua_pushboolean(L, r != 0);
  return 1;
}

static int b_or (lua_State *L) {
  int i, n = lua_gettop(L);
  b_uint r = 0;
  for (i = 1; i <= n; i++)
    r |= luaL_checkunsigned(L, i);
  lua_pushunsigned(L, trim(r));
  return 1;
}

static int b_xor (lua_State *L) {
  int i, n = lua_gettop(L);
  b_uint r = 0;
  for (i = 1; i <= n; i++)
    r ^= luaL_checkunsigned(L, i);
  lua_pushunsigned(L, trim(r));
  return 1;
}

static int b_not (lua_State *L) {
  b_uint r = ~luaL_checkunsigned(L, 1);
  lua_pushunsigned(L, trim(r));
  return 1;
}

static int b_shift (lua_State *L, b_uint r, int i) {
  if (i < 0) {  /* shift right? */
    i = -i;
    r = trim(r);
    if (i >= LUA_NBITS) r = 0;
    else r >>= i;
  }
  else {  /* shift left */
    if (i >= LUA_NBITS) r = 0;
    else r <<= i;
    r = trim(r);
  }
  lua_pushunsigned(L, r);
  return 1;
}

static int b_lshift (lua_State *L) {
  return b_shift(L, luaL_checkunsigned(L, 1), luaL_checkint(L, 2));
}

static int b_rshift (lua_State *L) {
  return b_shift(L, luaL_checkunsigned(L, 1), -luaL_checkint(L, 2));
}

static int b_arshift (lua_State *L) {
  b_uint r = luaL_checkunsigned(L, 1);
  int i = luaL_checkint(L, 2);
  if (i < 0 || !(r & ((b_uint)1 << (LUA_NBITS - 1))))
    return b_shift(L, r, -i);
  else {  /* arithmetic shift for 'negative' number */
    if (i >= LUA_NBITS) r = ALLONES;
    else
      r = trim((r >> i) | ~(~(b_uint)0 >> i));  /* add signal bit */
    lua_pushunsigned(L, r);
    return 1;
  }
}

static int b_rot (lua_State *L, int i) {
  b_uint r = luaL_checkunsigned(L, 1);
  i &= (LUA_NBITS - 1);  /* i = i % NBITS */
  r = trim(r);
  if (i != 0)  /* avoid undefined shift of LUA_NBITS when i == 0 */
    r = (r << i) | (r >> (LUA_NBITS - i));
  lua_pushunsigned(L, trim(r));
  return 1;
}

static int b_lrot (lua_State *L) {
  return b_rot(L, luaL_checkint(L, 2));
}

static int b_rrot (lua_State *L) {
  return b_rot(L, -luaL_checkint(L, 2));
}

/*
** get field and width arguments for field-manipulation functions,
** checking whether they are valid.
** ('luaL_error' called without 'return' to avoid later warnings about
** 'width' being used uninitialized.)
*/
static int fieldargs (lua_State *L, int farg, int *width) {
  int f = luaL_checkint(L, farg);
  int w = luaL_optint(L, farg + 1, 1);
  luaL_argcheck(L, 0 <= f, farg, "field cannot be negative");
  luaL_argcheck(L, 0 < w, farg + 1, "width must be positive");
  if (f + w > LUA_NBITS)
    luaL_error(L, "trying to access non-existent bits");
  *width = w;
  return f;
}

static int b_extract (lua_State *L) {
  int w;
  b_uint r = luaL_checkunsigned(L, 1);
  int f = fieldargs(L, 2, &w);
  r = (r >> f) & mask(w);
  lua_pushunsigned(L, r);
  return 1;
}

static int b_replace (lua_State *L) {
  int w;
  b_uint r = luaL_checkunsigned(L, 1);
  b_uint v = luaL_checkunsigned(L, 2);
  int f = fieldargs(L, 3, &w);
  int m = mask(w);
  v &= m;  /* erase bits outside given width */
  r = (r & ~(m << f)) | (v << f);
  lua_pushunsigned(L, r);
  return 1;
}

static const luaL_Reg bitlib[] = {
  {"arshift", b_arshift},
  {"band", b_and},
  {"bnot", b_not},
  {"bor", b_or},
  {"bxor", b_xor},
  {"btest", b_test},
  {"extract", b_extract},
  {"lrotate", b_lrot},
  {"lshift", b_lshift},
  {"replace", b_replace},
  {"rrotate", b_rrot},
  {"rshift", b_rshift},
  {NULL, NULL}
};

LUAMOD_API int luaopen_bit32 (lua_State *L) {
  luaL_newlib(L, bitlib);
  return 1;
}


text:
/*
** $Id: luac.c,v 1.69 2011/11/29 17:46:33 lhf Exp $
** Lua compiler (saves bytecodes to files; also list bytecodes)
** See Copyright Notice in lua.h
*/

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define luac_c
#define LUA_CORE

#include "lua.h"
#include "lauxlib.h"

#include "lobject.h"
#include "lstate.h"
#include "lundump.h"

static void PrintFunction(const Proto* f, int full);
#define luaU_print	PrintFunction

#define PROGNAME	"luac"		/* default program name */
#define OUTPUT		PROGNAME ".out"	/* default output file */

static int listing=0;			/* list bytecodes? */
static int dumping=1;			/* dump bytecodes? */
static int stripping=0;			/* strip debug information? */
static char Output[]={ OUTPUT };	/* default output file name */
static const char* output=Output;	/* actual output file name */
static const char* progname=PROGNAME;	/* actual program name */

static void fatal(const char* message)
{
 fprintf(stderr,"%s: %s\n",progname,message);
 exit(EXIT_FAILURE);
}

static void cannot(const char* what)
{
 fprintf(stderr,"%s: cannot %s %s: %s\n",progname,what,output,strerror(errno));
 exit(EXIT_FAILURE);
}

static void usage(const char* message)
{
 if (*message=='-')
  fprintf(stderr,"%s: unrecognized option " LUA_QS "\n",progname,message);
 else
  fprintf(stderr,"%s: %s\n",progname,message);
 fprintf(stderr,
  "usage: %s [options] [filenames]\n"
  "Available options are:\n"
  "  -l       list (use -l -l for full listing)\n"
  "  -o name  output to file " LUA_QL("name") " (default is \"%s\")\n"
  "  -p       parse only\n"
  "  -s       strip debug information\n"
  "  -v       show version information\n"
  "  --       stop handling options\n"
  "  -        stop handling options and process stdin\n"
  ,progname,Output);
 exit(EXIT_FAILURE);
}

#define IS(s)	(strcmp(argv[i],s)==0)

static int doargs(int argc, char* argv[])
{
 int i;
 int version=0;
 if (argv[0]!=NULL && *argv[0]!=0) progname=argv[0];
 for (i=1; i<argc; i++)
 {
  if (*argv[i]!='-')			/* end of options; keep it */
   break;
  else if (IS("--"))			/* end of options; skip it */
  {
   ++i;
   if (version) ++version;
   break;
  }
  else if (IS("-"))			/* end of options; use stdin */
   break;
  else if (IS("-l"))			/* list */
   ++listing;
  else if (IS("-o"))			/* output file */
  {
   output=argv[++i];
   if (output==NULL || *output==0 || (*output=='-' && output[1]!=0))
    usage(LUA_QL("-o") " needs argument");
   if (IS("-")) output=NULL;
  }
  else if (IS("-p"))			/* parse only */
   dumping=0;
  else if (IS("-s"))			/* strip debug information */
   stripping=1;
  else if (IS("-v"))			/* show version */
   ++version;
  else					/* unknown option */
   usage(argv[i]);
 }
 if (i==argc && (listing || !dumping))
 {
  dumping=0;
  argv[--i]=Output;
 }
 if (version)
 {
  printf("%s\n",LUA_COPYRIGHT);
  if (version==argc-1) exit(EXIT_SUCCESS);
 }
 return i;
}

#define FUNCTION "(function()end)();"

static const char* reader(lua_State *L, void *ud, size_t *size)
{
 UNUSED(L);
 if ((*(int*)ud)--)
 {
  *size=sizeof(FUNCTION)-1;
  return FUNCTION;
 }
 else
 {
  *size=0;
  return NULL;
 }
}

#define toproto(L,i) getproto(L->top+(i))

static const Proto* combine(lua_State* L, int n)
{
 if (n==1)
  return toproto(L,-1);
 else
 {
  Proto* f;
  int i=n;
  if (lua_load(L,reader,&i,"=(" PROGNAME ")",NULL)!=LUA_OK) fatal(lua_tostring(L,-1));
  f=toproto(L,-1);
  for (i=0; i<n; i++)
  {
   f->p[i]=toproto(L,i-n-1);
   if (f->p[i]->sizeupvalues>0) f->p[i]->upvalues[0].instack=0;
  }
  f->sizelineinfo=0;
  return f;
 }
}

static int writer(lua_State* L, const void* p, size_t size, void* u)
{
 UNUSED(L);
 return (fwrite(p,size,1,(FILE*)u)!=1) && (size!=0);
}

static int pmain(lua_State* L)
{
 int argc=(int)lua_tointeger(L,1);
 char** argv=(char**)lua_touserdata(L,2);
 const Proto* f;
 int i;
 if (!lua_checkstack(L,argc)) fatal("too many input files");
 for (i=0; i<argc; i++)
 {
  const char* filename=IS("-") ? NULL : argv[i];
  if (luaL_loadfile(L,filename)!=LUA_OK) fatal(lua_tostring(L,-1));
 }
 f=combine(L,argc);
 if (listing) luaU_print(f,listing>1);
 if (dumping)
 {
  FILE* D= (output==NULL) ? stdout : fopen(output,"wb");
  if (D==NULL) cannot("open");
  lua_lock(L);
  luaU_dump(L,f,writer,D,stripping);
  lua_unlock(L);
  if (ferror(D)) cannot("write");
  if (fclose(D)) cannot("close");
 }
 return 0;
}

int main(int argc, char* argv[])
{
 lua_State* L;
 int i=doargs(argc,argv);
 argc-=i; argv+=i;
 if (argc<=0) usage("no input files given");
 L=luaL_newstate();
 if (L==NULL) fatal("cannot create state: not enough memory");
 lua_pushcfunction(L,&pmain);
 lua_pushinteger(L,argc);
 lua_pushlightuserdata(L,argv);
 if (lua_pcall(L,2,0,0)!=LUA_OK) fatal(lua_tostring(L,-1));
 lua_close(L);
 return EXIT_SUCCESS;
}

/*
** $Id: print.c,v 1.69 2013/07/04 01:03:46 lhf Exp $
** print bytecodes
** See Copyright Notice in lua.h
*/

#include <ctype.h>
#include <stdio.h>

#define luac_c
#define LUA_CORE

#include "ldebug.h"
#include "lobject.h"
#include "lopcodes.h"

#define VOID(p)		((const void*)(p))

static void PrintString(const TString* ts)
{
 const char* s=getstr(ts);
 size_t i,n=ts->tsv.len;
 printf("%c",'"');
 for (i=0; i<n; i++)
 {
  int c=(int)(unsigned char)s[i];
  switch (c)
  {
   case '"':  printf("\\\""); break;
   case '\\': printf("\\\\"); break;
   case '\a': printf("\\a"); break;
   case '\b': printf("\\b"); break;
   case '\f': printf("\\f"); break;
   case '\n': printf("\\n"); break;
   case '\r': printf("\\r"); break;
   case '\t': printf("\\t"); break;
   case '\v': printf("\\v"); break;
   default:	if (isprint(c))
   			printf("%c",c);
		else
			printf("\\%03d",c);
  }
 }
 printf("%c",'"');
}

static void PrintConstant(const Proto* f, int i)
{
 const TValue* o=&f->k[i];
 switch (ttypenv(o))
 {
  case LUA_TNIL:
	printf("nil");
	break;
  case LUA_TBOOLEAN:
	printf(bvalue(o) ? "true" : "false");
	break;
  case LUA_TNUMBER:
	printf(LUA_NUMBER_FMT,nvalue(o));
	break;
  case LUA_TSTRING:
	PrintString(rawtsvalue(o));
	break;
  default:				/* cannot happen */
	printf("? type=%d",ttype(o));
	break;
 }
}

#define UPVALNAME(x) ((f->upvalues[x].name) ? getstr(f->upvalues[x].name) : "-")
#define MYK(x)		(-1-(x))

static void PrintCode(const Proto* f)
{
 const Instruction* code=f->code;
 int pc,n=f->sizecode;
 for (pc=0; pc<n; pc++)
 {
  Instruction i=code[pc];
  OpCode o=GET_OPCODE(i);
  int a=GETARG_A(i);
  int b=GETARG_B(i);
  int c=GETARG_C(i);
  int ax=GETARG_Ax(i);
  int bx=GETARG_Bx(i);
  int sbx=GETARG_sBx(i);
  int line=getfuncline(f,pc);
  printf("\t%d\t",pc+1);
  if (line>0) printf("[%d]\t",line); else printf("[-]\t");
  printf("%-9s\t",luaP_opnames[o]);
  switch (getOpMode(o))
  {
   case iABC:
    printf("%d",a);
    if (getBMode(o)!=OpArgN) printf(" %d",ISK(b) ? (MYK(INDEXK(b))) : b);
    if (getCMode(o)!=OpArgN) printf(" %d",ISK(c) ? (MYK(INDEXK(c))) : c);
    break;
   case iABx:
    printf("%d",a);
    if (getBMode(o)==OpArgK) printf(" %d",MYK(bx));
    if (getBMode(o)==OpArgU) printf(" %d",bx);
    break;
   case iAsBx:
    printf("%d %d",a,sbx);
    break;
   case iAx:
    printf("%d",MYK(ax));
    break;
  }
  switch (o)
  {
   case OP_LOADK:
    printf("\t; "); PrintConstant(f,bx);
    break;
   case OP_GETUPVAL:
   case OP_SETUPVAL:
    printf("\t; %s",UPVALNAME(b));
    break;
   case OP_GETTABUP:
    printf("\t; %s",UPVALNAME(b));
    if (ISK(c)) { printf(" "); PrintConstant(f,INDEXK(c)); }
    break;
   case OP_SETTABUP:
    printf("\t; %s",UPVALNAME(a));
    if (ISK(b)) { printf(" "); PrintConstant(f,INDEXK(b)); }
    if (ISK(c)) { printf(" "); PrintConstant(f,INDEXK(c)); }
    break;
   case OP_GETTABLE:
   case OP_SELF:
    if (ISK(c)) { printf("\t; "); PrintConstant(f,INDEXK(c)); }
    break;
   case OP_SETTABLE:
   case OP_ADD:
   case OP_SUB:
   case OP_MUL:
   case OP_DIV:
   case OP_POW:
   case OP_EQ:
   case OP_LT:
   case OP_LE:
    if (ISK(b) || ISK(c))
    {
     printf("\t; ");
     if (ISK(b)) PrintConstant(f,INDEXK(b)); else printf("-");
     printf(" ");
     if (ISK(c)) PrintConstant(f,INDEXK(c)); else printf("-");
    }
    break;
   case OP_JMP:
   case OP_FORLOOP:
   case OP_FORPREP:
   case OP_TFORLOOP:
    printf("\t; to %d",sbx+pc+2);
    break;
   case OP_CLOSURE:
    printf("\t; %p",VOID(f->p[bx]));
    break;
   case OP_SETLIST:
    if (c==0) printf("\t; %d",(int)code[++pc]); else printf("\t; %d",c);
    break;
   case OP_EXTRAARG:
    printf("\t; "); PrintConstant(f,ax);
    break;
   default:
    break;
  }
  printf("\n");
 }
}

#define SS(x)	((x==1)?"":"s")
#define S(x)	(int)(x),SS(x)

static void PrintHeader(const Proto* f)
{
 const char* s=f->source ? getstr(f->source) : "=?";
 if (*s=='@' || *s=='=')
  s++;
 else if (*s==LUA_SIGNATURE[0])
  s="(bstring)";
 else
  s="(string)";
 printf("\n%s <%s:%d,%d> (%d instruction%s at %p)\n",
 	(f->linedefined==0)?"main":"function",s,
	f->linedefined,f->lastlinedefined,
	S(f->sizecode),VOID(f));
 printf("%d%s param%s, %d slot%s, %d upvalue%s, ",
	(int)(f->numparams),f->is_vararg?"+":"",SS(f->numparams),
	S(f->maxstacksize),S(f->sizeupvalues));
 printf("%d local%s, %d constant%s, %d function%s\n",
	S(f->sizelocvars),S(f->sizek),S(f->sizep));
}

static void PrintDebug(const Proto* f)
{
 int i,n;
 n=f->sizek;
 printf("constants (%d) for %p:\n",n,VOID(f));
 for (i=0; i<n; i++)
 {
  printf("\t%d\t",i+1);
  PrintConstant(f,i);
  printf("\n");
 }
 n=f->sizelocvars;
 printf("locals (%d) for %p:\n",n,VOID(f));
 for (i=0; i<n; i++)
 {
  printf("\t%d\t%s\t%d\t%d\n",
  i,getstr(f->locvars[i].varname),f->locvars[i].startpc+1,f->locvars[i].endpc+1);
 }
 n=f->sizeupvalues;
 printf("upvalues (%d) for %p:\n",n,VOID(f));
 for (i=0; i<n; i++)
 {
  printf("\t%d\t%s\t%d\t%d\n",
  i,UPVALNAME(i),f->upvalues[i].instack,f->upvalues[i].idx);
 }
}

static void PrintFunction(const Proto* f, int full)
{
 int i,n=f->sizep;
 PrintHeader(f);
 PrintCode(f);
 if (full) PrintDebug(f);
 for (i=0; i<n; i++) PrintFunction(f->p[i],full);
}


text:
/*
** $Id: lopcodes.c,v 1.49.1.1 2013/04/12 18:48:47 roberto Exp $
** Opcodes for Lua virtual machine
** See Copyright Notice in lua.h
*/

#define lopcodes_c
#define LUA_CORE

#include "lopcodes.h"

/* ORDER OP */

LUAI_DDEF const char *const luaP_opnames[NUM_OPCODES+1] = {
  "MOVE",
  "LOADK",
  "LOADKX",
  "LOADBOOL",
  "LOADNIL",
  "GETUPVAL",
  "GETTABUP",
  "GETTABLE",
  "SETTABUP",
  "SETUPVAL",
  "SETTABLE",
  "NEWTABLE",
  "SELF",
  "ADD",
  "SUB",
  "MUL",
  "DIV",
  "MOD",
  "POW",
  "UNM",
  "NOT",
  "LEN",
  "CONCAT",
  "JMP",
  "EQ",
  "LT",
  "LE",
  "TEST",
  "TESTSET",
  "CALL",
  "TAILCALL",
  "RETURN",
  "FORLOOP",
  "FORPREP",
  "TFORCALL",
  "TFORLOOP",
  "SETLIST",
  "CLOSURE",
  "VARARG",
  "EXTRAARG",
  NULL
};

#define opmode(t,a,b,c,m) (((t)<<7) | ((a)<<6) | ((b)<<4) | ((c)<<2) | (m))

LUAI_DDEF const lu_byte luaP_opmodes[NUM_OPCODES] = {
/*       T  A    B       C     mode		   opcode	*/
  opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_MOVE */
 ,opmode(0, 1, OpArgK, OpArgN, iABx)		/* OP_LOADK */
 ,opmode(0, 1, OpArgN, OpArgN, iABx)		/* OP_LOADKX */
 ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_LOADBOOL */
 ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_LOADNIL */
 ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_GETUPVAL */
 ,opmode(0, 1, OpArgU, OpArgK, iABC)		/* OP_GETTABUP */
 ,opmode(0, 1, OpArgR, OpArgK, iABC)		/* OP_GETTABLE */
 ,opmode(0, 0, OpArgK, OpArgK, iABC)		/* OP_SETTABUP */
 ,opmode(0, 0, OpArgU, OpArgN, iABC)		/* OP_SETUPVAL */
 ,opmode(0, 0, OpArgK, OpArgK, iABC)		/* OP_SETTABLE */
 ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_NEWTABLE */
 ,opmode(0, 1, OpArgR, OpArgK, iABC)		/* OP_SELF */
 ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_ADD */
 ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_SUB */
 ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_MUL */
 ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_DIV */
 ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_MOD */
 ,opmode(0, 1, OpArgK, OpArgK, iABC)		/* OP_POW */
 ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_UNM */
 ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_NOT */
 ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_LEN */
 ,opmode(0, 1, OpArgR, OpArgR, iABC)		/* OP_CONCAT */
 ,opmode(0, 0, OpArgR, OpArgN, iAsBx)		/* OP_JMP */
 ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_EQ */
 ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_LT */
 ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_LE */
 ,opmode(1, 0, OpArgN, OpArgU, iABC)		/* OP_TEST */
 ,opmode(1, 1, OpArgR, OpArgU, iABC)		/* OP_TESTSET */
 ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_CALL */
 ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_TAILCALL */
 ,opmode(0, 0, OpArgU, OpArgN, iABC)		/* OP_RETURN */
 ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_FORLOOP */
 ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_FORPREP */
 ,opmode(0, 0, OpArgN, OpArgU, iABC)		/* OP_TFORCALL */
 ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_TFORLOOP */
 ,opmode(0, 0, OpArgU, OpArgU, iABC)		/* OP_SETLIST */
 ,opmode(0, 1, OpArgU, OpArgN, iABx)		/* OP_CLOSURE */
 ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_VARARG */
 ,opmode(0, 0, OpArgU, OpArgU, iAx)		/* OP_EXTRAARG */
};


text:
/*
** $Id: ltable.h,v 2.16.1.2 2013/08/30 15:49:41 roberto Exp $
** Lua tables (hash)
** See Copyright Notice in lua.h
*/

#ifndef ltable_h
#define ltable_h

#include "lobject.h"

#define gnode(t,i)	(&(t)->node[i])
#define gkey(n)		(&(n)->i_key.tvk)
#define gval(n)		(&(n)->i_val)
#define gnext(n)	((n)->i_key.nk.next)

#define invalidateTMcache(t)	((t)->flags = 0)

/* returns the key, given the value of a table entry */
#define keyfromval(v) \
  (gkey(cast(Node *, cast(char *, (v)) - offsetof(Node, i_val))))

LUAI_FUNC const TValue *luaH_getint (Table *t, int key);
LUAI_FUNC void luaH_setint (lua_State *L, Table *t, int key, TValue *value);
LUAI_FUNC const TValue *luaH_getstr (Table *t, TString *key);
LUAI_FUNC const TValue *luaH_get (Table *t, const TValue *key);
LUAI_FUNC TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key);
LUAI_FUNC TValue *luaH_set (lua_State *L, Table *t, const TValue *key);
LUAI_FUNC Table *luaH_new (lua_State *L);
LUAI_FUNC void luaH_resize (lua_State *L, Table *t, int nasize, int nhsize);
LUAI_FUNC void luaH_resizearray (lua_State *L, Table *t, int nasize);
LUAI_FUNC void luaH_free (lua_State *L, Table *t);
LUAI_FUNC int luaH_next (lua_State *L, Table *t, StkId key);
LUAI_FUNC int luaH_getn (Table *t);

#if defined(LUA_DEBUG)
LUAI_FUNC Node *luaH_mainposition (const Table *t, const TValue *key);
LUAI_FUNC int luaH_isdummy (Node *n);
#endif

#endif


text:
/*
** $Id: lualib.h,v 1.43.1.1 2013/04/12 18:48:47 roberto Exp $
** Lua standard libraries
** See Copyright Notice in lua.h
*/

#ifndef lualib_h
#define lualib_h

#include "lua.h"

LUAMOD_API int (luaopen_base) (lua_State *L);

#define LUA_COLIBNAME	"coroutine"
LUAMOD_API int (luaopen_coroutine) (lua_State *L);

#define LUA_TABLIBNAME	"table"
LUAMOD_API int (luaopen_table) (lua_State *L);

#define LUA_IOLIBNAME	"io"
LUAMOD_API int (luaopen_io) (lua_State *L);

#define LUA_OSLIBNAME	"os"
LUAMOD_API int (luaopen_os) (lua_State *L);

#define LUA_STRLIBNAME	"string"
LUAMOD_API int (luaopen_string) (lua_State *L);

#define LUA_BITLIBNAME	"bit32"
LUAMOD_API int (luaopen_bit32) (lua_State *L);

#define LUA_MATHLIBNAME	"math"
LUAMOD_API int (luaopen_math) (lua_State *L);

#define LUA_DBLIBNAME	"debug"
LUAMOD_API int (luaopen_debug) (lua_State *L);

#define LUA_LOADLIBNAME	"package"
LUAMOD_API int (luaopen_package) (lua_State *L);

/* open all previous libraries */
LUALIB_API void (luaL_openlibs) (lua_State *L);

#if !defined(lua_assert)
#define lua_assert(x)	((void)0)
#endif

#endif


text:
/*
** $Id: lcorolib.c,v 1.5.1.1 2013/04/12 18:48:47 roberto Exp $
** Coroutine Library
** See Copyright Notice in lua.h
*/

#include <stdlib.h>

#define lcorolib_c
#define LUA_LIB

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"

static int auxresume (lua_State *L, lua_State *co, int narg) {
  int status;
  if (!lua_checkstack(co, narg)) {
    lua_pushliteral(L, "too many arguments to resume");
    return -1;  /* error flag */
  }
  if (lua_status(co) == LUA_OK && lua_gettop(co) == 0) {
    lua_pushliteral(L, "cannot resume dead coroutine");
    return -1;  /* error flag */
  }
  lua_xmove(L, co, narg);
  status = lua_resume(co, L, narg);
  if (status == LUA_OK || status == LUA_YIELD) {
    int nres = lua_gettop(co);
    if (!lua_checkstack(L, nres + 1)) {
      lua_pop(co, nres);  /* remove results anyway */
      lua_pushliteral(L, "too many results to resume");
      return -1;  /* error flag */
    }
    lua_xmove(co, L, nres);  /* move yielded values */
    return nres;
  }
  else {
    lua_xmove(co, L, 1);  /* move error message */
    return -1;  /* error flag */
  }
}

static int luaB_coresume (lua_State *L) {
  lua_State *co = lua_tothread(L, 1);
  int r;
  luaL_argcheck(L, co, 1, "coroutine expected");
  r = auxresume(L, co, lua_gettop(L) - 1);
  if (r < 0) {
    lua_pushboolean(L, 0);
    lua_insert(L, -2);
    return 2;  /* return false + error message */
  }
  else {
    lua_pushboolean(L, 1);
    lua_insert(L, -(r + 1));
    return r + 1;  /* return true + `resume' returns */
  }
}

static int luaB_auxwrap (lua_State *L) {
  lua_State *co = lua_tothread(L, lua_upvalueindex(1));
  int r = auxresume(L, co, lua_gettop(L));
  if (r < 0) {
    if (lua_isstring(L, -1)) {  /* error object is a string? */
      luaL_where(L, 1);  /* add extra info */
      lua_insert(L, -2);
      lua_concat(L, 2);
    }
    return lua_error(L);  /* propagate error */
  }
  return r;
}

static int luaB_cocreate (lua_State *L) {
  lua_State *NL;
  luaL_checktype(L, 1, LUA_TFUNCTION);
  NL = lua_newthread(L);
  lua_pushvalue(L, 1);  /* move function to top */
  lua_xmove(L, NL, 1);  /* move function from L to NL */
  return 1;
}

static int luaB_cowrap (lua_State *L) {
  luaB_cocreate(L);
  lua_pushcclosure(L, luaB_auxwrap, 1);
  return 1;
}

static int luaB_yield (lua_State *L) {
  return lua_yield(L, lua_gettop(L));
}

static int luaB_costatus (lua_State *L) {
  lua_State *co = lua_tothread(L, 1);
  luaL_argcheck(L, co, 1, "coroutine expected");
  if (L == co) lua_pushliteral(L, "running");
  else {
    switch (lua_status(co)) {
      case LUA_YIELD:
        lua_pushliteral(L, "suspended");
        break;
      case LUA_OK: {
        lua_Debug ar;
        if (lua_getstack(co, 0, &ar) > 0)  /* does it have frames? */
          lua_pushliteral(L, "normal");  /* it is running */
        else if (lua_gettop(co) == 0)
            lua_pushliteral(L, "dead");
        else
          lua_pushliteral(L, "suspended");  /* initial state */
        break;
      }
      default:  /* some error occurred */
        lua_pushliteral(L, "dead");
        break;
    }
  }
  return 1;
}

static int luaB_corunning (lua_State *L) {
  int ismain = lua_pushthread(L);
  lua_pushboolean(L, ismain);
  return 2;
}

static const luaL_Reg co_funcs[] = {
  {"create", luaB_cocreate},
  {"resume", luaB_coresume},
  {"running", luaB_corunning},
  {"status", luaB_costatus},
  {"wrap", luaB_cowrap},
  {"yield", luaB_yield},
  {NULL, NULL}
};

LUAMOD_API int luaopen_coroutine (lua_State *L) {
  luaL_newlib(L, co_funcs);
  return 1;
}


text:
/*
** $Id: lstrlib.c,v 1.178.1.1 2013/04/12 18:48:47 roberto Exp $
** Standard library for string operations and pattern-matching
** See Copyright Notice in lua.h
*/

#include <ctype.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define lstrlib_c
#define LUA_LIB

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"

/*
** maximum number of captures that a pattern can do during
** pattern-matching. This limit is arbitrary.
*/
#if !defined(LUA_MAXCAPTURES)
#define LUA_MAXCAPTURES		32
#endif

/* macro to `unsign' a character */
#define uchar(c)	((unsigned char)(c))

static int str_len (lua_State *L) {
  size_t l;
  luaL_checklstring(L, 1, &l);
  lua_pushinteger(L, (lua_Integer)l);
  return 1;
}

/* translate a relative string position: negative means back from end */
static size_t posrelat (ptrdiff_t pos, size_t len) {
  if (pos >= 0) return (size_t)pos;
  else if (0u - (size_t)pos > len) return 0;
  else return len - ((size_t)-pos) + 1;
}

static int str_sub (lua_State *L) {
  size_t l;
  const char *s = luaL_checklstring(L, 1, &l);
  size_t start = posrelat(luaL_checkinteger(L, 2), l);
  size_t end = posrelat(luaL_optinteger(L, 3, -1), l);
  if (start < 1) start = 1;
  if (end > l) end = l;
  if (start <= end)
    lua_pushlstring(L, s + start - 1, end - start + 1);
  else lua_pushliteral(L, "");
  return 1;
}

static int str_reverse (lua_State *L) {
  size_t l, i;
  luaL_Buffer b;
  const char *s = luaL_checklstring(L, 1, &l);
  char *p = luaL_buffinitsize(L, &b, l);
  for (i = 0; i < l; i++)
    p[i] = s[l - i - 1];
  luaL_pushresultsize(&b, l);
  return 1;
}

static int str_lower (lua_State *L) {
  size_t l;
  size_t i;
  luaL_Buffer b;
  const char *s = luaL_checklstring(L, 1, &l);
  char *p = luaL_buffinitsize(L, &b, l);
  for (i=0; i<l; i++)
    p[i] = tolower(uchar(s[i]));
  luaL_pushresultsize(&b, l);
  return 1;
}

static int str_upper (lua_State *L) {
  size_t l;
  size_t i;
  luaL_Buffer b;
  const char *s = luaL_checklstring(L, 1, &l);
  char *p = luaL_buffinitsize(L, &b, l);
  for (i=0; i<l; i++)
    p[i] = toupper(uchar(s[i]));
  luaL_pushresultsize(&b, l);
  return 1;
}

/* reasonable limit to avoid arithmetic overflow */
#define MAXSIZE		((~(size_t)0) >> 1)

static int str_rep (lua_State *L) {
  size_t l, lsep;
  const char *s = luaL_checklstring(L, 1, &l);
  int n = luaL_checkint(L, 2);
  const char *sep = luaL_optlstring(L, 3, "", &lsep);
  if (n <= 0) lua_pushliteral(L, "");
  else if (l + lsep < l || l + lsep >= MAXSIZE / n)  /* may overflow? */
    return luaL_error(L, "resulting string too large");
  else {
    size_t totallen = n * l + (n - 1) * lsep;
    luaL_Buffer b;
    char *p = luaL_buffinitsize(L, &b, totallen);
    while (n-- > 1) {  /* first n-1 copies (followed by separator) */
      memcpy(p, s, l * sizeof(char)); p += l;
      if (lsep > 0) {  /* avoid empty 'memcpy' (may be expensive) */
        memcpy(p, sep, lsep * sizeof(char)); p += lsep;
      }
    }
    memcpy(p, s, l * sizeof(char));  /* last copy (not followed by separator) */
    luaL_pushresultsize(&b, totallen);
  }
  return 1;
}

static int str_byte (lua_State *L) {
  size_t l;
  const char *s = luaL_checklstring(L, 1, &l);
  size_t posi = posrelat(luaL_optinteger(L, 2, 1), l);
  size_t pose = posrelat(luaL_optinteger(L, 3, posi), l);
  int n, i;
  if (posi < 1) posi = 1;
  if (pose > l) pose = l;
  if (posi > pose) return 0;  /* empty interval; return no values */
  n = (int)(pose -  posi + 1);
  if (posi + n <= pose)  /* (size_t -> int) overflow? */
    return luaL_error(L, "string slice too long");
  luaL_checkstack(L, n, "string slice too long");
  for (i=0; i<n; i++)
    lua_pushinteger(L, uchar(s[posi+i-1]));
  return n;
}

static int str_char (lua_State *L) {
  int n = lua_gettop(L);  /* number of arguments */
  int i;
  luaL_Buffer b;
  char *p = luaL_buffinitsize(L, &b, n);
  for (i=1; i<=n; i++) {
    int c = luaL_checkint(L, i);
    luaL_argcheck(L, uchar(c) == c, i, "value out of range");
    p[i - 1] = uchar(c);
  }
  luaL_pushresultsize(&b, n);
  return 1;
}

static int writer (lua_State *L, const void* b, size_t size, void* B) {
  (void)L;
  luaL_addlstring((luaL_Buffer*) B, (const char *)b, size);
  return 0;
}

static int str_dump (lua_State *L) {
  luaL_Buffer b;
  luaL_checktype(L, 1, LUA_TFUNCTION);
  lua_settop(L, 1);
  luaL_buffinit(L,&b);
  if (lua_dump(L, writer, &b) != 0)
    return luaL_error(L, "unable to dump given function");
  luaL_pushresult(&b);
  return 1;
}

/*
** {======================================================
** PATTERN MATCHING
** =======================================================
*/

#define CAP_UNFINISHED	(-1)
#define CAP_POSITION	(-2)

typedef struct MatchState {
  int matchdepth;  /* control for recursive depth (to avoid C stack overflow) */
  const char *src_init;  /* init of source string */
  const char *src_end;  /* end ('\0') of source string */
  const char *p_end;  /* end ('\0') of pattern */
  lua_State *L;
  int level;  /* total number of captures (finished or unfinished) */
  struct {
    const char *init;
    ptrdiff_t len;
  } capture[LUA_MAXCAPTURES];
} MatchState;

/* recursive function */
static const char *match (MatchState *ms, const char *s, const char *p);

/* maximum recursion depth for 'match' */
#if !defined(MAXCCALLS)
#define MAXCCALLS	200
#endif

#define L_ESC		'%'
#define SPECIALS	"^$*+?.([%-"

static int check_capture (MatchState *ms, int l) {
  l -= '1';
  if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
    return luaL_error(ms->L, "invalid capture index %%%d", l + 1);
  return l;
}

static int capture_to_close (MatchState *ms) {
  int level = ms->level;
  for (level--; level>=0; level--)
    if (ms->capture[level].len == CAP_UNFINISHED) return level;
  return luaL_error(ms->L, "invalid pattern capture");
}

static const char *classend (MatchState *ms, const char *p) {
  switch (*p++) {
    case L_ESC: {
      if (p == ms->p_end)
        luaL_error(ms->L, "malformed pattern (ends with " LUA_QL("%%") ")");
      return p+1;
    }
    case '[': {
      if (*p == '^') p++;
      do {  /* look for a `]' */
        if (p == ms->p_end)
          luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")");
        if (*(p++) == L_ESC && p < ms->p_end)
          p++;  /* skip escapes (e.g. `%]') */
      } while (*p != ']');
      return p+1;
    }
    default: {
      return p;
    }
  }
}

static int match_class (int c, int cl) {
  int res;
  switch (tolower(cl)) {
    case 'a' : res = isalpha(c); break;
    case 'c' : res = iscntrl(c); break;
    case 'd' : res = isdigit(c); break;
    case 'g' : res = isgraph(c); break;
    case 'l' : res = islower(c); break;
    case 'p' : res = ispunct(c); break;
    case 's' : res = isspace(c); break;
    case 'u' : res = isupper(c); break;
    case 'w' : res = isalnum(c); break;
    case 'x' : res = isxdigit(c); break;
    case 'z' : res = (c == 0); break;  /* deprecated option */
    default: return (cl == c);
  }
  return (islower(cl) ? res : !res);
}

static int matchbracketclass (int c, const char *p, const char *ec) {
  int sig = 1;
  if (*(p+1) == '^') {
    sig = 0;
    p++;  /* skip the `^' */
  }
  while (++p < ec) {
    if (*p == L_ESC) {
      p++;
      if (match_class(c, uchar(*p)))
        return sig;
    }
    else if ((*(p+1) == '-') && (p+2 < ec)) {
      p+=2;
      if (uchar(*(p-2)) <= c && c <= uchar(*p))
        return sig;
    }
    else if (uchar(*p) == c) return sig;
  }
  return !sig;
}

static int singlematch (MatchState *ms, const char *s, const char *p,
                        const char *ep) {
  if (s >= ms->src_end)
    return 0;
  else {
    int c = uchar(*s);
    switch (*p) {
      case '.': return 1;  /* matches any char */
      case L_ESC: return match_class(c, uchar(*(p+1)));
      case '[': return matchbracketclass(c, p, ep-1);
      default:  return (uchar(*p) == c);
    }
  }
}

static const char *matchbalance (MatchState *ms, const char *s,
                                   const char *p) {
  if (p >= ms->p_end - 1)
    luaL_error(ms->L, "malformed pattern "
                      "(missing arguments to " LUA_QL("%%b") ")");
  if (*s != *p) return NULL;
  else {
    int b = *p;
    int e = *(p+1);
    int cont = 1;
    while (++s < ms->src_end) {
      if (*s == e) {
        if (--cont == 0) return s+1;
      }
      else if (*s == b) cont++;
    }
  }
  return NULL;  /* string ends out of balance */
}

static const char *max_expand (MatchState *ms, const char *s,
                                 const char *p, const char *ep) {
  ptrdiff_t i = 0;  /* counts maximum expand for item */
  while (singlematch(ms, s + i, p, ep))
    i++;
  /* keeps trying to match with the maximum repetitions */
  while (i>=0) {
    const char *res = match(ms, (s+i), ep+1);
    if (res) return res;
    i--;  /* else didn't match; reduce 1 repetition to try again */
  }
  return NULL;
}

static const char *min_expand (MatchState *ms, const char *s,
                                 const char *p, const char *ep) {
  for (;;) {
    const char *res = match(ms, s, ep+1);
    if (res != NULL)
      return res;
    else if (singlematch(ms, s, p, ep))
      s++;  /* try with one more repetition */
    else return NULL;
  }
}

static const char *start_capture (MatchState *ms, const char *s,
                                    const char *p, int what) {
  const char *res;
  int level = ms->level;
  if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
  ms->capture[level].init = s;
  ms->capture[level].len = what;
  ms->level = level+1;
  if ((res=match(ms, s, p)) == NULL)  /* match failed? */
    ms->level--;  /* undo capture */
  return res;
}

static const char *end_capture (MatchState *ms, const char *s,
                                  const char *p) {
  int l = capture_to_close(ms);
  const char *res;
  ms->capture[l].len = s - ms->capture[l].init;  /* close capture */
  if ((res = match(ms, s, p)) == NULL)  /* match failed? */
    ms->capture[l].len = CAP_UNFINISHED;  /* undo capture */
  return res;
}

static const char *match_capture (MatchState *ms, const char *s, int l) {
  size_t len;
  l = check_capture(ms, l);
  len = ms->capture[l].len;
  if ((size_t)(ms->src_end-s) >= len &&
      memcmp(ms->capture[l].init, s, len) == 0)
    return s+len;
  else return NULL;
}

static const char *match (MatchState *ms, const char *s, const char *p) {
  if (ms->matchdepth-- == 0)
    luaL_error(ms->L, "pattern too complex");
  init: /* using goto's to optimize tail recursion */
  if (p != ms->p_end) {  /* end of pattern? */
    switch (*p) {
      case '(': {  /* start capture */
        if (*(p + 1) == ')')  /* position capture? */
          s = start_capture(ms, s, p + 2, CAP_POSITION);
        else
          s = start_capture(ms, s, p + 1, CAP_UNFINISHED);
        break;
      }
      case ')': {  /* end capture */
        s = end_capture(ms, s, p + 1);
        break;
      }
      case '$': {
        if ((p + 1) != ms->p_end)  /* is the `$' the last char in pattern? */
          goto dflt;  /* no; go to default */
        s = (s == ms->src_end) ? s : NULL;  /* check end of string */
        break;
      }
      case L_ESC: {  /* escaped sequences not in the format class[*+?-]? */
        switch (*(p + 1)) {
          case 'b': {  /* balanced string? */
            s = matchbalance(ms, s, p + 2);
            if (s != NULL) {
              p += 4; goto init;  /* return match(ms, s, p + 4); */
            }  /* else fail (s == NULL) */
            break;
          }
          case 'f': {  /* frontier? */
            const char *ep; char previous;
            p += 2;
            if (*p != '[')
              luaL_error(ms->L, "missing " LUA_QL("[") " after "
                                 LUA_QL("%%f") " in pattern");
            ep = classend(ms, p);  /* points to what is next */
            previous = (s == ms->src_init) ? '\0' : *(s - 1);
            if (!matchbracketclass(uchar(previous), p, ep - 1) &&
               matchbracketclass(uchar(*s), p, ep - 1)) {
              p = ep; goto init;  /* return match(ms, s, ep); */
            }
            s = NULL;  /* match failed */
            break;
          }
          case '0': case '1': case '2': case '3':
          case '4': case '5': case '6': case '7':
          case '8': case '9': {  /* capture results (%0-%9)? */
            s = match_capture(ms, s, uchar(*(p + 1)));
            if (s != NULL) {
              p += 2; goto init;  /* return match(ms, s, p + 2) */
            }
            break;
          }
          default: goto dflt;
        }
        break;
      }
      default: dflt: {  /* pattern class plus optional suffix */
        const char *ep = classend(ms, p);  /* points to optional suffix */
        /* does not match at least once? */
        if (!singlematch(ms, s, p, ep)) {
          if (*ep == '*' || *ep == '?' || *ep == '-') {  /* accept empty? */
            p = ep + 1; goto init;  /* return match(ms, s, ep + 1); */
          }
          else  /* '+' or no suffix */
            s = NULL;  /* fail */
        }
        else {  /* matched once */
          switch (*ep) {  /* handle optional suffix */
            case '?': {  /* optional */
              const char *res;
              if ((res = match(ms, s + 1, ep + 1)) != NULL)
                s = res;
              else {
                p = ep + 1; goto init;  /* else return match(ms, s, ep + 1); */
              }
              break;
            }
            case '+':  /* 1 or more repetitions */
              s++;  /* 1 match already done */
              /* go through */
            case '*':  /* 0 or more repetitions */
              s = max_expand(ms, s, p, ep);
              break;
            case '-':  /* 0 or more repetitions (minimum) */
              s = min_expand(ms, s, p, ep);
              break;
            default:  /* no suffix */
              s++; p = ep; goto init;  /* return match(ms, s + 1, ep); */
          }
        }
        break;
      }
    }
  }
  ms->matchdepth++;
  return s;
}

static const char *lmemfind (const char *s1, size_t l1,
                               const char *s2, size_t l2) {
  if (l2 == 0) return s1;  /* empty strings are everywhere */
  else if (l2 > l1) return NULL;  /* avoids a negative `l1' */
  else {
    const char *init;  /* to search for a `*s2' inside `s1' */
    l2--;  /* 1st char will be checked by `memchr' */
    l1 = l1-l2;  /* `s2' cannot be found after that */
    while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
      init++;   /* 1st char is already checked */
      if (memcmp(init, s2+1, l2) == 0)
        return init-1;
      else {  /* correct `l1' and `s1' to try again */
        l1 -= init-s1;
        s1 = init;
      }
    }
    return NULL;  /* not found */
  }
}

static void push_onecapture (MatchState *ms, int i, const char *s,
                                                    const char *e) {
  if (i >= ms->level) {
    if (i == 0)  /* ms->level == 0, too */
      lua_pushlstring(ms->L, s, e - s);  /* add whole match */
    else
      luaL_error(ms->L, "invalid capture index");
  }
  else {
    ptrdiff_t l = ms->capture[i].len;
    if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture");
    if (l == CAP_POSITION)
      lua_pushinteger(ms->L, ms->capture[i].init - ms->src_init + 1);
    else
      lua_pushlstring(ms->L, ms->capture[i].init, l);
  }
}

static int push_captures (MatchState *ms, const char *s, const char *e) {
  int i;
  int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
  luaL_checkstack(ms->L, nlevels, "too many captures");
  for (i = 0; i < nlevels; i++)
    push_onecapture(ms, i, s, e);
  return nlevels;  /* number of strings pushed */
}

/* check whether pattern has no special characters */
static int nospecials (const char *p, size_t l) {
  size_t upto = 0;
  do {
    if (strpbrk(p + upto, SPECIALS))
      return 0;  /* pattern has a special character */
    upto += strlen(p + upto) + 1;  /* may have more after \0 */
  } while (upto <= l);
  return 1;  /* no special chars found */
}

static int str_find_aux (lua_State *L, int find) {
  size_t ls, lp;
  const char *s = luaL_checklstring(L, 1, &ls);
  const char *p = luaL_checklstring(L, 2, &lp);
  size_t init = posrelat(luaL_optinteger(L, 3, 1), ls);
  if (init < 1) init = 1;
  else if (init > ls + 1) {  /* start after string's end? */
    lua_pushnil(L);  /* cannot find anything */
    return 1;
  }
  /* explicit request or no special characters? */
  if (find && (lua_toboolean(L, 4) || nospecials(p, lp))) {
    /* do a plain search */
    const char *s2 = lmemfind(s + init - 1, ls - init + 1, p, lp);
    if (s2) {
      lua_pushinteger(L, s2 - s + 1);
      lua_pushinteger(L, s2 - s + lp);
      return 2;
    }
  }
  else {
    MatchState ms;
    const char *s1 = s + init - 1;
    int anchor = (*p == '^');
    if (anchor) {
      p++; lp--;  /* skip anchor character */
    }
    ms.L = L;
    ms.matchdepth = MAXCCALLS;
    ms.src_init = s;
    ms.src_end = s + ls;
    ms.p_end = p + lp;
    do {
      const char *res;
      ms.level = 0;
      lua_assert(ms.matchdepth == MAXCCALLS);
      if ((res=match(&ms, s1, p)) != NULL) {
        if (find) {
          lua_pushinteger(L, s1 - s + 1);  /* start */
          lua_pushinteger(L, res - s);   /* end */
          return push_captures(&ms, NULL, 0) + 2;
        }
        else
          return push_captures(&ms, s1, res);
      }
    } while (s1++ < ms.src_end && !anchor);
  }
  lua_pushnil(L);  /* not found */
  return 1;
}

static int str_find (lua_State *L) {
  return str_find_aux(L, 1);
}

static int str_match (lua_State *L) {
  return str_find_aux(L, 0);
}

static int gmatch_aux (lua_State *L) {
  MatchState ms;
  size_t ls, lp;
  const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls);
  const char *p = lua_tolstring(L, lua_upvalueindex(2), &lp);
  const char *src;
  ms.L = L;
  ms.matchdepth = MAXCCALLS;
  ms.src_init = s;
  ms.src_end = s+ls;
  ms.p_end = p + lp;
  for (src = s + (size_t)lua_tointeger(L, lua_upvalueindex(3));
       src <= ms.src_end;
       src++) {
    const char *e;
    ms.level = 0;
    lua_assert(ms.matchdepth == MAXCCALLS);
    if ((e = match(&ms, src, p)) != NULL) {
      lua_Integer newstart = e-s;
      if (e == src) newstart++;  /* empty match? go at least one position */
      lua_pushinteger(L, newstart);
      lua_replace(L, lua_upvalueindex(3));
      return push_captures(&ms, src, e);
    }
  }
  return 0;  /* not found */
}

static int gmatch (lua_State *L) {
  luaL_checkstring(L, 1);
  luaL_checkstring(L, 2);
  lua_settop(L, 2);
  lua_pushinteger(L, 0);
  lua_pushcclosure(L, gmatch_aux, 3);
  return 1;
}

static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
                                                   const char *e) {
  size_t l, i;
  const char *news = lua_tolstring(ms->L, 3, &l);
  for (i = 0; i < l; i++) {
    if (news[i] != L_ESC)
      luaL_addchar(b, news[i]);
    else {
      i++;  /* skip ESC */
      if (!isdigit(uchar(news[i]))) {
        if (news[i] != L_ESC)
          luaL_error(ms->L, "invalid use of " LUA_QL("%c")
                           " in replacement string", L_ESC);
        luaL_addchar(b, news[i]);
      }
      else if (news[i] == '0')
          luaL_addlstring(b, s, e - s);
      else {
        push_onecapture(ms, news[i] - '1', s, e);
        luaL_addvalue(b);  /* add capture to accumulated result */
      }
    }
  }
}

static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
                                       const char *e, int tr) {
  lua_State *L = ms->L;
  switch (tr) {
    case LUA_TFUNCTION: {
      int n;
      lua_pushvalue(L, 3);
      n = push_captures(ms, s, e);
      lua_call(L, n, 1);
      break;
    }
    case LUA_TTABLE: {
      push_onecapture(ms, 0, s, e);
      lua_gettable(L, 3);
      break;
    }
    default: {  /* LUA_TNUMBER or LUA_TSTRING */
      add_s(ms, b, s, e);
      return;
    }
  }
  if (!lua_toboolean(L, -1)) {  /* nil or false? */
    lua_pop(L, 1);
    lua_pushlstring(L, s, e - s);  /* keep original text */
  }
  else if (!lua_isstring(L, -1))
    luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1));
  luaL_addvalue(b);  /* add result to accumulator */
}

static int str_gsub (lua_State *L) {
  size_t srcl, lp;
  const char *src = luaL_checklstring(L, 1, &srcl);
  const char *p = luaL_checklstring(L, 2, &lp);
  int tr = lua_type(L, 3);
  size_t max_s = luaL_optinteger(L, 4, srcl+1);
  int anchor = (*p == '^');
  size_t n = 0;
  MatchState ms;
  luaL_Buffer b;
  luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
                   tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
                      "string/function/table expected");
  luaL_buffinit(L, &b);
  if (anchor) {
    p++; lp--;  /* skip anchor character */
  }
  ms.L = L;
  ms.matchdepth = MAXCCALLS;
  ms.src_init = src;
  ms.src_end = src+srcl;
  ms.p_end = p + lp;
  while (n < max_s) {
    const char *e;
    ms.level = 0;
    lua_assert(ms.matchdepth == MAXCCALLS);
    e = match(&ms, src, p);
    if (e) {
      n++;
      add_value(&ms, &b, src, e, tr);
    }
    if (e && e>src) /* non empty match? */
      src = e;  /* skip it */
    else if (src < ms.src_end)
      luaL_addchar(&b, *src++);
    else break;
    if (anchor) break;
  }
  luaL_addlstring(&b, src, ms.src_end-src);
  luaL_pushresult(&b);
  lua_pushinteger(L, n);  /* number of substitutions */
  return 2;
}

/* }====================================================== */

/*
** {======================================================
** STRING FORMAT
** =======================================================
*/

/*
** LUA_INTFRMLEN is the length modifier for integer conversions in
** 'string.format'; LUA_INTFRM_T is the integer type corresponding to
** the previous length
*/
#if !defined(LUA_INTFRMLEN)	/* { */
#if defined(LUA_USE_LONGLONG)

#define LUA_INTFRMLEN		"ll"
#define LUA_INTFRM_T		long long

#else

#define LUA_INTFRMLEN		"l"
#define LUA_INTFRM_T		long

#endif
#endif				/* } */

/*
** LUA_FLTFRMLEN is the length modifier for float conversions in
** 'string.format'; LUA_FLTFRM_T is the float type corresponding to
** the previous length
*/
#if !defined(LUA_FLTFRMLEN)

#define LUA_FLTFRMLEN		""
#define LUA_FLTFRM_T		double

#endif

/* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
#define MAX_ITEM	512
/* valid flags in a format specification */
#define FLAGS	"-+ #0"
/*
** maximum size of each format specification (such as '%-099.99d')
** (+10 accounts for %99.99x plus margin of error)
*/
#define MAX_FORMAT	(sizeof(FLAGS) + sizeof(LUA_INTFRMLEN) + 10)

static void addquoted (lua_State *L, luaL_Buffer *b, int arg) {
  size_t l;
  const char *s = luaL_checklstring(L, arg, &l);
  luaL_addchar(b, '"');
  while (l--) {
    if (*s == '"' || *s == '\\' || *s == '\n') {
      luaL_addchar(b, '\\');
      luaL_addchar(b, *s);
    }
    else if (*s == '\0' || iscntrl(uchar(*s))) {
      char buff[10];
      if (!isdigit(uchar(*(s+1))))
        sprintf(buff, "\\%d", (int)uchar(*s));
      else
        sprintf(buff, "\\%03d", (int)uchar(*s));
      luaL_addstring(b, buff);
    }
    else
      luaL_addchar(b, *s);
    s++;
  }
  luaL_addchar(b, '"');
}

static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
  const char *p = strfrmt;
  while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++;  /* skip flags */
  if ((size_t)(p - strfrmt) >= sizeof(FLAGS)/sizeof(char))
    luaL_error(L, "invalid format (repeated flags)");
  if (isdigit(uchar(*p))) p++;  /* skip width */
  if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
  if (*p == '.') {
    p++;
    if (isdigit(uchar(*p))) p++;  /* skip precision */
    if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
  }
  if (isdigit(uchar(*p)))
    luaL_error(L, "invalid format (width or precision too long)");
  *(form++) = '%';
  memcpy(form, strfrmt, (p - strfrmt + 1) * sizeof(char));
  form += p - strfrmt + 1;
  *form = '\0';
  return p;
}

/*
** add length modifier into formats
*/
static void addlenmod (char *form, const char *lenmod) {
  size_t l = strlen(form);
  size_t lm = strlen(lenmod);
  char spec = form[l - 1];
  strcpy(form + l - 1, lenmod);
  form[l + lm - 1] = spec;
  form[l + lm] = '\0';
}

static int str_format (lua_State *L) {
  int top = lua_gettop(L);
  int arg = 1;
  size_t sfl;
  const char *strfrmt = luaL_checklstring(L, arg, &sfl);
  const char *strfrmt_end = strfrmt+sfl;
  luaL_Buffer b;
  luaL_buffinit(L, &b);
  while (strfrmt < strfrmt_end) {
    if (*strfrmt != L_ESC)
      luaL_addchar(&b, *strfrmt++);
    else if (*++strfrmt == L_ESC)
      luaL_addchar(&b, *strfrmt++);  /* %% */
    else { /* format item */
      char form[MAX_FORMAT];  /* to store the format (`%...') */
      char *buff = luaL_prepbuffsize(&b, MAX_ITEM);  /* to put formatted item */
      int nb = 0;  /* number of bytes in added item */
      if (++arg > top)
        luaL_argerror(L, arg, "no value");
      strfrmt = scanformat(L, strfrmt, form);
      switch (*strfrmt++) {
        case 'c': {
          nb = sprintf(buff, form, luaL_checkint(L, arg));
          break;
        }
        case 'd': case 'i': {
          lua_Number n = luaL_checknumber(L, arg);
          LUA_INTFRM_T ni = (LUA_INTFRM_T)n;
          lua_Number diff = n - (lua_Number)ni;
          luaL_argcheck(L, -1 < diff && diff < 1, arg,
                        "not a number in proper range");
          addlenmod(form, LUA_INTFRMLEN);
          nb = sprintf(buff, form, ni);
          break;
        }
        case 'o': case 'u': case 'x': case 'X': {
          lua_Number n = luaL_checknumber(L, arg);
          unsigned LUA_INTFRM_T ni = (unsigned LUA_INTFRM_T)n;
          lua_Number diff = n - (lua_Number)ni;
          luaL_argcheck(L, -1 < diff && diff < 1, arg,
                        "not a non-negative number in proper range");
          addlenmod(form, LUA_INTFRMLEN);
          nb = sprintf(buff, form, ni);
          break;
        }
        case 'e': case 'E': case 'f':
#if defined(LUA_USE_AFORMAT)
        case 'a': case 'A':
#endif
        case 'g': case 'G': {
          addlenmod(form, LUA_FLTFRMLEN);
          nb = sprintf(buff, form, (LUA_FLTFRM_T)luaL_checknumber(L, arg));
          break;
        }
        case 'q': {
          addquoted(L, &b, arg);
          break;
        }
        case 's': {
          size_t l;
          const char *s = luaL_tolstring(L, arg, &l);
          if (!strchr(form, '.') && l >= 100) {
            /* no precision and string is too long to be formatted;
               keep original string */
            luaL_addvalue(&b);
            break;
          }
          else {
            nb = sprintf(buff, form, s);
            lua_pop(L, 1);  /* remove result from 'luaL_tolstring' */
            break;
          }
        }
        default: {  /* also treat cases `pnLlh' */
          return luaL_error(L, "invalid option " LUA_QL("%%%c") " to "
                               LUA_QL("format"), *(strfrmt - 1));
        }
      }
      luaL_addsize(&b, nb);
    }
  }
  luaL_pushresult(&b);
  return 1;
}

/* }====================================================== */

static const luaL_Reg strlib[] = {
  {"byte", str_byte},
  {"char", str_char},
  {"dump", str_dump},
  {"find", str_find},
  {"format", str_format},
  {"gmatch", gmatch},
  {"gsub", str_gsub},
  {"len", str_len},
  {"lower", str_lower},
  {"match", str_match},
  {"rep", str_rep},
  {"reverse", str_reverse},
  {"sub", str_sub},
  {"upper", str_upper},
  {NULL, NULL}
};

static void createmetatable (lua_State *L) {
  lua_createtable(L, 0, 1);  /* table to be metatable for strings */
  lua_pushliteral(L, "");  /* dummy string */
  lua_pushvalue(L, -2);  /* copy table */
  lua_setmetatable(L, -2);  /* set table as metatable for strings */
  lua_pop(L, 1);  /* pop dummy string */
  lua_pushvalue(L, -2);  /* get string library */
  lua_setfield(L, -2, "__index");  /* metatable.__index = string */
  lua_pop(L, 1);  /* pop metatable */
}

/*
** Open string library
*/
LUAMOD_API int luaopen_string (lua_State *L) {
  luaL_newlib(L, strlib);
  createmetatable(L);
  return 1;
}


text:
/*
** $Id: lmathlib.c,v 1.83.1.1 2013/04/12 18:48:47 roberto Exp $
** Standard mathematical library
** See Copyright Notice in lua.h
*/

#include <stdlib.h>
#include <math.h>

#define lmathlib_c
#define LUA_LIB

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"

#undef PI
#define PI	((lua_Number)(3.1415926535897932384626433832795))
#define RADIANS_PER_DEGREE	((lua_Number)(PI/180.0))

static int math_abs (lua_State *L) {
  lua_pushnumber(L, l_mathop(fabs)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_sin (lua_State *L) {
  lua_pushnumber(L, l_mathop(sin)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_sinh (lua_State *L) {
  lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_cos (lua_State *L) {
  lua_pushnumber(L, l_mathop(cos)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_cosh (lua_State *L) {
  lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_tan (lua_State *L) {
  lua_pushnumber(L, l_mathop(tan)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_tanh (lua_State *L) {
  lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_asin (lua_State *L) {
  lua_pushnumber(L, l_mathop(asin)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_acos (lua_State *L) {
  lua_pushnumber(L, l_mathop(acos)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_atan (lua_State *L) {
  lua_pushnumber(L, l_mathop(atan)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_atan2 (lua_State *L) {
  lua_pushnumber(L, l_mathop(atan2)(luaL_checknumber(L, 1),
                                luaL_checknumber(L, 2)));
  return 1;
}

static int math_ceil (lua_State *L) {
  lua_pushnumber(L, l_mathop(ceil)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_floor (lua_State *L) {
  lua_pushnumber(L, l_mathop(floor)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_fmod (lua_State *L) {
  lua_pushnumber(L, l_mathop(fmod)(luaL_checknumber(L, 1),
                               luaL_checknumber(L, 2)));
  return 1;
}

static int math_modf (lua_State *L) {
  lua_Number ip;
  lua_Number fp = l_mathop(modf)(luaL_checknumber(L, 1), &ip);
  lua_pushnumber(L, ip);
  lua_pushnumber(L, fp);
  return 2;
}

static int math_sqrt (lua_State *L) {
  lua_pushnumber(L, l_mathop(sqrt)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_pow (lua_State *L) {
  lua_Number x = luaL_checknumber(L, 1);
  lua_Number y = luaL_checknumber(L, 2);
  lua_pushnumber(L, l_mathop(pow)(x, y));
  return 1;
}

static int math_log (lua_State *L) {
  lua_Number x = luaL_checknumber(L, 1);
  lua_Number res;
  if (lua_isnoneornil(L, 2))
    res = l_mathop(log)(x);
  else {
    lua_Number base = luaL_checknumber(L, 2);
    if (base == (lua_Number)10.0) res = l_mathop(log10)(x);
    else res = l_mathop(log)(x)/l_mathop(log)(base);
  }
  lua_pushnumber(L, res);
  return 1;
}

#if defined(LUA_COMPAT_LOG10)
static int math_log10 (lua_State *L) {
  lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
  return 1;
}
#endif

static int math_exp (lua_State *L) {
  lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
  return 1;
}

static int math_deg (lua_State *L) {
  lua_pushnumber(L, luaL_checknumber(L, 1)/RADIANS_PER_DEGREE);
  return 1;
}

static int math_rad (lua_State *L) {
  lua_pushnumber(L, luaL_checknumber(L, 1)*RADIANS_PER_DEGREE);
  return 1;
}

static int math_frexp (lua_State *L) {
  int e;
  lua_pushnumber(L, l_mathop(frexp)(luaL_checknumber(L, 1), &e));
  lua_pushinteger(L, e);
  return 2;
}

static int math_ldexp (lua_State *L) {
  lua_Number x = luaL_checknumber(L, 1);
  int ep = luaL_checkint(L, 2);
  lua_pushnumber(L, l_mathop(ldexp)(x, ep));
  return 1;
}

static int math_min (lua_State *L) {
  int n = lua_gettop(L);  /* number of arguments */
  lua_Number dmin = luaL_checknumber(L, 1);
  int i;
  for (i=2; i<=n; i++) {
    lua_Number d = luaL_checknumber(L, i);
    if (d < dmin)
      dmin = d;
  }
  lua_pushnumber(L, dmin);
  return 1;
}

static int math_max (lua_State *L) {
  int n = lua_gettop(L);  /* number of arguments */
  lua_Number dmax = luaL_checknumber(L, 1);
  int i;
  for (i=2; i<=n; i++) {
    lua_Number d = luaL_checknumber(L, i);
    if (d > dmax)
      dmax = d;
  }
  lua_pushnumber(L, dmax);
  return 1;
}

static int math_random (lua_State *L) {
  /* the `%' avoids the (rare) case of r==1, and is needed also because on
     some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */
  lua_Number r = (lua_Number)(rand()%RAND_MAX) / (lua_Number)RAND_MAX;
  switch (lua_gettop(L)) {  /* check number of arguments */
    case 0: {  /* no arguments */
      lua_pushnumber(L, r);  /* Number between 0 and 1 */
      break;
    }
    case 1: {  /* only upper limit */
      lua_Number u = luaL_checknumber(L, 1);
      luaL_argcheck(L, (lua_Number)1.0 <= u, 1, "interval is empty");
      lua_pushnumber(L, l_mathop(floor)(r*u) + (lua_Number)(1.0));  /* [1, u] */
      break;
    }
    case 2: {  /* lower and upper limits */
      lua_Number l = luaL_checknumber(L, 1);
      lua_Number u = luaL_checknumber(L, 2);
      luaL_argcheck(L, l <= u, 2, "interval is empty");
      lua_pushnumber(L, l_mathop(floor)(r*(u-l+1)) + l);  /* [l, u] */
      break;
    }
    default: return luaL_error(L, "wrong number of arguments");
  }
  return 1;
}

static int math_randomseed (lua_State *L) {
  srand(luaL_checkunsigned(L, 1));
  (void)rand(); /* discard first value to avoid undesirable correlations */
  return 0;
}

static const luaL_Reg mathlib[] = {
  {"abs",   math_abs},
  {"acos",  math_acos},
  {"asin",  math_asin},
  {"atan2", math_atan2},
  {"atan",  math_atan},
  {"ceil",  math_ceil},
  {"cosh",   math_cosh},
  {"cos",   math_cos},
  {"deg",   math_deg},
  {"exp",   math_exp},
  {"floor", math_floor},
  {"fmod",   math_fmod},
  {"frexp", math_frexp},
  {"ldexp", math_ldexp},
#if defined(LUA_COMPAT_LOG10)
  {"log10", math_log10},
#endif
  {"log",   math_log},
  {"max",   math_max},
  {"min",   math_min},
  {"modf",   math_modf},
  {"pow",   math_pow},
  {"rad",   math_rad},
  {"random",     math_random},
  {"randomseed", math_randomseed},
  {"sinh",   math_sinh},
  {"sin",   math_sin},
  {"sqrt",  math_sqrt},
  {"tanh",   math_tanh},
  {"tan",   math_tan},
  {NULL, NULL}
};

/*
** Open math library
*/
LUAMOD_API int luaopen_math (lua_State *L) {
  luaL_newlib(L, mathlib);
  lua_pushnumber(L, PI);
  lua_setfield(L, -2, "pi");
  lua_pushnumber(L, HUGE_VAL);
  lua_setfield(L, -2, "huge");
  return 1;
}