eval.c

早期freebsd实现

	    anum = st[1]->str_cur;
	else {
	    anum = (int) str_gnum(st[3]) - arybase + st[2]->str_cur;
	    if (anum < 0)
		anum = 0;
	    else if (anum > st[1]->str_cur)
		anum = st[1]->str_cur;
	}
#ifndef lint
	if (!(tmps2 = rninstr(tmps,  tmps  + anum,
			      tmps2, tmps2 + st[2]->str_cur)))
#else
	if (tmps2 = rninstr(Nullch,Nullch,Nullch,Nullch))
#endif
	    value = (double)(-1 + arybase);
	else
	    value = (double)(tmps2 - tmps + arybase);
	goto donumset;
    case O_TIME:
#ifndef lint
	value = (double) time(Null(long*));
#endif
	goto donumset;
    case O_TMS:
	sp = do_tms(str,gimme,arglast);
	goto array_return;
    case O_LOCALTIME:
	if (maxarg < 1)
	    (void)time(&when);
	else
	    when = (time_t)str_gnum(st[1]);
	sp = do_time(str,localtime(&when),
	  gimme,arglast);
	goto array_return;
    case O_GMTIME:
	if (maxarg < 1)
	    (void)time(&when);
	else
	    when = (time_t)str_gnum(st[1]);
	sp = do_time(str,gmtime(&when),
	  gimme,arglast);
	goto array_return;
    case O_TRUNCATE:
	sp = do_truncate(str,arg,
	  gimme,arglast);
	goto array_return;
    case O_LSTAT:
    case O_STAT:
	sp = do_stat(str,arg,
	  gimme,arglast);
	goto array_return;
    case O_CRYPT:
#ifdef HAS_CRYPT
	tmps = str_get(st[1]);
#ifdef FCRYPT
	str_set(str,fcrypt(tmps,str_get(st[2])));
#else
	str_set(str,crypt(tmps,str_get(st[2])));
#endif
#else
	fatal(
	  "The crypt() function is unimplemented due to excessive paranoia.");
#endif
	break;
    case O_ATAN2:
	value = str_gnum(st[1]);
	value = atan2(value,str_gnum(st[2]));
	goto donumset;
    case O_SIN:
	if (maxarg < 1)
	    value = str_gnum(stab_val(defstab));
	else
	    value = str_gnum(st[1]);
	value = sin(value);
	goto donumset;
    case O_COS:
	if (maxarg < 1)
	    value = str_gnum(stab_val(defstab));
	else
	    value = str_gnum(st[1]);
	value = cos(value);
	goto donumset;
    case O_RAND:
	if (maxarg < 1)
	    value = 1.0;
	else
	    value = str_gnum(st[1]);
	if (value == 0.0)
	    value = 1.0;
#if RANDBITS == 31
	value = rand() * value / 2147483648.0;
#else
#if RANDBITS == 16
	value = rand() * value / 65536.0;
#else
#if RANDBITS == 15
	value = rand() * value / 32768.0;
#else
	value = rand() * value / (double)(((unsigned long)1) << RANDBITS);
#endif
#endif
#endif
	goto donumset;
    case O_SRAND:
	if (maxarg < 1) {
	    (void)time(&when);
	    anum = when;
	}
	else
	    anum = (int)str_gnum(st[1]);
	(void)srand(anum);
	goto say_yes;
    case O_EXP:
	if (maxarg < 1)
	    value = str_gnum(stab_val(defstab));
	else
	    value = str_gnum(st[1]);
	value = exp(value);
	goto donumset;
    case O_LOG:
	if (maxarg < 1)
	    value = str_gnum(stab_val(defstab));
	else
	    value = str_gnum(st[1]);
	if (value <= 0.0)
	    fatal("Can't take log of %g\n", value);
	value = log(value);
	goto donumset;
    case O_SQRT:
	if (maxarg < 1)
	    value = str_gnum(stab_val(defstab));
	else
	    value = str_gnum(st[1]);
	if (value < 0.0)
	    fatal("Can't take sqrt of %g\n", value);
	value = sqrt(value);
	goto donumset;
    case O_INT:
	if (maxarg < 1)
	    value = str_gnum(stab_val(defstab));
	else
	    value = str_gnum(st[1]);
	if (value >= 0.0)
	    (void)modf(value,&value);
	else {
	    (void)modf(-value,&value);
	    value = -value;
	}
	goto donumset;
    case O_ORD:
	if (maxarg < 1)
	    tmps = str_get(stab_val(defstab));
	else
	    tmps = str_get(st[1]);
#ifndef I286
	value = (double) (*tmps & 255);
#else
	anum = (int) *tmps;
	value = (double) (anum & 255);
#endif
	goto donumset;
    case O_ALARM:
#ifdef HAS_ALARM
	if (maxarg < 1)
	    tmps = str_get(stab_val(defstab));
	else
	    tmps = str_get(st[1]);
	if (!tmps)
	    tmps = "0";
	anum = alarm((unsigned int)atoi(tmps));
	if (anum < 0)
	    goto say_undef;
	value = (double)anum;
	goto donumset;
#else
	fatal("Unsupported function alarm");
	break;
#endif
    case O_SLEEP:
	if (maxarg < 1)
	    tmps = Nullch;
	else
	    tmps = str_get(st[1]);
	(void)time(&when);
	if (!tmps || !*tmps)
	    sleep((32767<<16)+32767);
	else
	    sleep((unsigned int)atoi(tmps));
#ifndef lint
	value = (double)when;
	(void)time(&when);
	value = ((double)when) - value;
#endif
	goto donumset;
    case O_RANGE:
	sp = do_range(gimme,arglast);
	goto array_return;
    case O_F_OR_R:
	if (gimme == G_ARRAY) {		/* it's a range */
	    /* can we optimize to constant array? */
	    if ((arg[1].arg_type & A_MASK) == A_SINGLE &&
	      (arg[2].arg_type & A_MASK) == A_SINGLE) {
		st[2] = arg[2].arg_ptr.arg_str;
		sp = do_range(gimme,arglast);
		st = stack->ary_array;
		maxarg = sp - arglast[0];
		str_free(arg[1].arg_ptr.arg_str);
		arg[1].arg_ptr.arg_str = Nullstr;
		str_free(arg[2].arg_ptr.arg_str);
		arg[2].arg_ptr.arg_str = Nullstr;
		arg->arg_type = O_ARRAY;
		arg[1].arg_type = A_STAB|A_DONT;
		arg->arg_len = 1;
		stab = arg[1].arg_ptr.arg_stab = aadd(genstab());
		ary = stab_array(stab);
		afill(ary,maxarg - 1);
		anum = maxarg;
		st += arglast[0]+1;
		while (maxarg-- > 0)
		    ary->ary_array[maxarg] = str_smake(st[maxarg]);
		st -= arglast[0]+1;
		goto array_return;
	    }
	    arg->arg_type = optype = O_RANGE;
	    maxarg = arg->arg_len = 2;
	    anum = 2;
	    arg[anum].arg_flags &= ~AF_ARYOK;
	    argflags = arg[anum].arg_flags;
	    argtype = arg[anum].arg_type & A_MASK;
	    arg[anum].arg_type = argtype;
	    argptr = arg[anum].arg_ptr;
	    sp = arglast[0];
	    st -= sp;
	    sp++;
	    goto re_eval;
	}
	arg->arg_type = O_FLIP;
	/* FALL THROUGH */
    case O_FLIP:
	if ((arg[1].arg_type & A_MASK) == A_SINGLE ?
	  last_in_stab && (int)str_gnum(st[1]) == stab_io(last_in_stab)->lines
	  :
	  str_true(st[1]) ) {
	    arg[2].arg_type &= ~A_DONT;
	    arg[1].arg_type |= A_DONT;
	    arg->arg_type = optype = O_FLOP;
	    if (arg->arg_flags & AF_COMMON) {
		str_numset(str,0.0);
		anum = 2;
		argflags = arg[2].arg_flags;
		argtype = arg[2].arg_type & A_MASK;
		argptr = arg[2].arg_ptr;
		sp = arglast[0];
		st -= sp++;
		goto re_eval;
	    }
	    else {
		str_numset(str,1.0);
		break;
	    }
	}
	str_set(str,"");
	break;
    case O_FLOP:
	str_inc(str);
	if ((arg[2].arg_type & A_MASK) == A_SINGLE ?
	  last_in_stab && (int)str_gnum(st[2]) == stab_io(last_in_stab)->lines
	  :
	  str_true(st[2]) ) {
	    arg->arg_type = O_FLIP;
	    arg[1].arg_type &= ~A_DONT;
	    arg[2].arg_type |= A_DONT;
	    str_cat(str,"E0");
	}
	break;
    case O_FORK:
#ifdef HAS_FORK
	anum = fork();
	if (anum < 0)
	    goto say_undef;
	if (!anum) {
	    /*SUPPRESS 560*/
	    if (tmpstab = stabent("$",allstabs))
		str_numset(STAB_STR(tmpstab),(double)getpid());
	    hclear(pidstatus, FALSE);	/* no kids, so don't wait for 'em */
	}
	value = (double)anum;
	goto donumset;
#else
	fatal("Unsupported function fork");
	break;
#endif
    case O_WAIT:
#ifdef HAS_WAIT
#ifndef lint
	anum = wait(&argflags);
	if (anum > 0)
	    pidgone(anum,argflags);
	value = (double)anum;
#endif
	statusvalue = (unsigned short)argflags;
	goto donumset;
#else
	fatal("Unsupported function wait");
	break;
#endif
    case O_WAITPID:
#ifdef HAS_WAIT
#ifndef lint
	anum = (int)str_gnum(st[1]);
	optype = (int)str_gnum(st[2]);
	anum = wait4pid(anum, &argflags,optype);
	value = (double)anum;
#endif
	statusvalue = (unsigned short)argflags;
	goto donumset;
#else
	fatal("Unsupported function wait");
	break;
#endif
    case O_SYSTEM:
#ifdef HAS_FORK
#ifdef TAINT
	if (arglast[2] - arglast[1] == 1) {
	    taintenv();
	    tainted |= st[2]->str_tainted;
	    taintproper("Insecure dependency in system");
	}
#endif
	while ((anum = vfork()) == -1) {
	    if (errno != EAGAIN) {
		value = -1.0;
		goto donumset;
	    }
	    sleep(5);
	}
	if (anum > 0) {
#ifndef lint
	    ihand = signal(SIGINT, SIG_IGN);
	    qhand = signal(SIGQUIT, SIG_IGN);
	    argtype = wait4pid(anum, &argflags, 0);
#else
	    ihand = qhand = 0;
#endif
	    (void)signal(SIGINT, ihand);
	    (void)signal(SIGQUIT, qhand);
	    statusvalue = (unsigned short)argflags;
	    if (argtype < 0)
		value = -1.0;
	    else {
		value = (double)((unsigned int)argflags & 0xffff);
	    }
	    do_execfree();	/* free any memory child malloced on vfork */
	    goto donumset;
	}
	if ((arg[1].arg_type & A_MASK) == A_STAB)
	    value = (double)do_aexec(st[1],arglast);
	else if (arglast[2] - arglast[1] != 1)
	    value = (double)do_aexec(Nullstr,arglast);
	else {
	    value = (double)do_exec(str_get(str_mortal(st[2])));
	}
	_exit(-1);
#else /* ! FORK */
	if ((arg[1].arg_type & A_MASK) == A_STAB)
	    value = (double)do_aspawn(st[1],arglast);
	else if (arglast[2] - arglast[1] != 1)
	    value = (double)do_aspawn(Nullstr,arglast);
	else {
	    value = (double)do_spawn(str_get(str_mortal(st[2])));
	}
	goto donumset;
#endif /* FORK */
    case O_EXEC_OP:
	if ((arg[1].arg_type & A_MASK) == A_STAB)
	    value = (double)do_aexec(st[1],arglast);
	else if (arglast[2] - arglast[1] != 1)
	    value = (double)do_aexec(Nullstr,arglast);
	else {
#ifdef TAINT
	    taintenv();
	    tainted |= st[2]->str_tainted;
	    taintproper("Insecure dependency in exec");
#endif
	    value = (double)do_exec(str_get(str_mortal(st[2])));
	}
	goto donumset;
    case O_HEX:
	if (maxarg < 1)
	    tmps = str_get(stab_val(defstab));
	else
	    tmps = str_get(st[1]);
	value = (double)scanhex(tmps, 99, &argtype);
	goto donumset;

    case O_OCT:
	if (maxarg < 1)
	    tmps = str_get(stab_val(defstab));
	else
	    tmps = str_get(st[1]);
	while (*tmps && (isSPACE(*tmps) || *tmps == '0'))
	    tmps++;
	if (*tmps == 'x')
	    value = (double)scanhex(++tmps, 99, &argtype);
	else
	    value = (double)scanoct(tmps, 99, &argtype);
	goto donumset;

/* These common exits are hidden here in the middle of the switches for the
   benefit of those machines with limited branch addressing.  Sigh.  */

array_return:
#ifdef DEBUGGING
    if (debug) {
	dlevel--;
	if (debug & 8) {
	    anum = sp - arglast[0];
	    switch (anum) {
	    case 0:
		deb("%s RETURNS ()\n",opname[optype]);
		break;
	    case 1:
		deb("%s RETURNS (\"%s\")\n",opname[optype],
		    st[1] ? str_get(st[1]) : "");
		break;
	    default:
		tmps = st[1] ? str_get(st[1]) : "";
		deb("%s RETURNS %d ARGS (\"%s\",%s\"%s\")\n",opname[optype],
		  anum,tmps,anum==2?"":"...,",
			st[anum] ? str_get(st[anum]) : "");
		break;
	    }
	}
    }
#endif
    return sp;

say_yes:
    str = &str_yes;
    goto normal_return;

say_no:
    str = &str_no;
    goto normal_return;

say_undef:
    str = &str_undef;
    goto normal_return;

say_zero:
    value = 0.0;
    /* FALL THROUGH */

donumset:
    str_numset(str,value);
    STABSET(str);
    st[1] = str;
#ifdef DEBUGGING
    if (debug) {
	dlevel--;
	if (debug & 8)
	    deb("%s RETURNS \"%f\"\n",opname[optype],value);
    }
#endif
    return arglast[0] + 1;
#ifdef SMALLSWITCHES
    }
    else
    switch (optype) {
#endif
    case O_CHOWN:
#ifdef HAS_CHOWN
	value = (double)apply(optype,arglast);
	goto donumset;
#else
	fatal("Unsupported function chown");
	break;
#endif
    case O_KILL:
#ifdef HAS_KILL
	value = (double)apply(optype,arglast);
	goto donumset;
#else
	fatal("Unsupported function kill");
	break;
#endif
    case O_UNLINK:
    case O_CHMOD:
    case O_UTIME:
	value = (double)apply(optype,arglast);
	goto donumset;
    case O_UMASK:
#ifdef HAS_UMASK
	if (maxarg < 1) {
	    anum = umask(0);
	    (void)umask(anum);
	}
	else
	    anum = umask((int)str_gnum(st[1]));
	value = (double)anum;
#ifdef TAINT
	taintproper("Insecure dependency in umask");
#endif
	goto donumset;
#else
	fatal("Unsupported function umask");
	break;
#endif
#if defined(HAS_MSG) || defined(HAS_SEM) || defined(HAS_SHM)
    case O_MSGGET:
    case O_SHMGET:
    case O_SEMGET:
	if ((anum = do_ipcget(optype, arglast)) == -1)
	    goto say_undef;
	value = (double)anum;
	goto donumset;
    case O_MSGCTL:
    case O_SHMCTL:
    case O_SEMCTL:
	anum = do_ipcctl(optype, arglast);
	if (anum == -1)
	    goto say_undef;
	if (anum != 0) {
	    value = (double)anum;
	    goto donumset;
	}
	str_set(str,"0 but true");
	STABSET(str);
	break;
    case O_MSGSND:
	value = (double)(do_msgsnd(arglast) >= 0);
	goto donumset;
    case O_MSGRCV:
	value = (double)(do_msgrcv(arglast) >= 0);
	goto donumset;
    case O_SEMOP:
	value = (double)(do_semop(arglast) >= 0);
	goto donumset;
    case O_SHMREAD:
    case O_SHMWRITE:
	value = (double)(do_shmio(optype, arglast) >= 0);
	goto donumset;
#else /* not SYSVIPC */
    case O_MSGGET:
    case O_MSGCTL:
    case O_MSGSND:
    case O_MSGRCV:
    case O_SEMGET:
    case O_SEMCTL:
    case O_SEMOP:
    case O_SHMGET: