673 lines
12 KiB
Plaintext
673 lines
12 KiB
Plaintext
%{
|
|
/* Written by Pace Willisson (pace@blitz.com)
|
|
* and placed in the public domain.
|
|
*
|
|
* Largely rewritten by J.T. Conklin (jtc@wimsey.com)
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
|
|
#include <ctype.h>
|
|
#include <err.h>
|
|
#include <errno.h>
|
|
#include <inttypes.h>
|
|
#include <limits.h>
|
|
#include <locale.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <regex.h>
|
|
#include <unistd.h>
|
|
|
|
/*
|
|
* POSIX specifies a specific error code for syntax errors. We exit
|
|
* with this code for all errors.
|
|
*/
|
|
#define ERR_EXIT 2
|
|
|
|
enum valtype {
|
|
integer, numeric_string, string
|
|
} ;
|
|
|
|
struct val {
|
|
enum valtype type;
|
|
union {
|
|
char *s;
|
|
intmax_t i;
|
|
} u;
|
|
} ;
|
|
|
|
struct val *result;
|
|
|
|
int chk_div(intmax_t, intmax_t);
|
|
int chk_minus(intmax_t, intmax_t, intmax_t);
|
|
int chk_plus(intmax_t, intmax_t, intmax_t);
|
|
int chk_times(intmax_t, intmax_t, intmax_t);
|
|
void free_value(struct val *);
|
|
int is_zero_or_null(struct val *);
|
|
int isstring(struct val *);
|
|
struct val *make_integer(intmax_t);
|
|
struct val *make_str(const char *);
|
|
struct val *op_and(struct val *, struct val *);
|
|
struct val *op_colon(struct val *, struct val *);
|
|
struct val *op_div(struct val *, struct val *);
|
|
struct val *op_eq(struct val *, struct val *);
|
|
struct val *op_ge(struct val *, struct val *);
|
|
struct val *op_gt(struct val *, struct val *);
|
|
struct val *op_le(struct val *, struct val *);
|
|
struct val *op_lt(struct val *, struct val *);
|
|
struct val *op_minus(struct val *, struct val *);
|
|
struct val *op_ne(struct val *, struct val *);
|
|
struct val *op_or(struct val *, struct val *);
|
|
struct val *op_plus(struct val *, struct val *);
|
|
struct val *op_rem(struct val *, struct val *);
|
|
struct val *op_times(struct val *, struct val *);
|
|
intmax_t to_integer(struct val *);
|
|
void to_string(struct val *);
|
|
int yyerror(const char *);
|
|
int yylex(void);
|
|
int yyparse(void);
|
|
|
|
static int eflag;
|
|
char **av;
|
|
%}
|
|
|
|
%union
|
|
{
|
|
struct val *val;
|
|
}
|
|
|
|
%left <val> '|'
|
|
%left <val> '&'
|
|
%left <val> '=' '>' '<' GE LE NE
|
|
%left <val> '+' '-'
|
|
%left <val> '*' '/' '%'
|
|
%left <val> ':'
|
|
|
|
%token <val> TOKEN
|
|
%type <val> start expr
|
|
|
|
%%
|
|
|
|
start: expr { result = $$; }
|
|
|
|
expr: TOKEN
|
|
| '(' expr ')' { $$ = $2; }
|
|
| expr '|' expr { $$ = op_or ($1, $3); }
|
|
| expr '&' expr { $$ = op_and ($1, $3); }
|
|
| expr '=' expr { $$ = op_eq ($1, $3); }
|
|
| expr '>' expr { $$ = op_gt ($1, $3); }
|
|
| expr '<' expr { $$ = op_lt ($1, $3); }
|
|
| expr GE expr { $$ = op_ge ($1, $3); }
|
|
| expr LE expr { $$ = op_le ($1, $3); }
|
|
| expr NE expr { $$ = op_ne ($1, $3); }
|
|
| expr '+' expr { $$ = op_plus ($1, $3); }
|
|
| expr '-' expr { $$ = op_minus ($1, $3); }
|
|
| expr '*' expr { $$ = op_times ($1, $3); }
|
|
| expr '/' expr { $$ = op_div ($1, $3); }
|
|
| expr '%' expr { $$ = op_rem ($1, $3); }
|
|
| expr ':' expr { $$ = op_colon ($1, $3); }
|
|
;
|
|
|
|
|
|
%%
|
|
|
|
struct val *
|
|
make_integer(intmax_t i)
|
|
{
|
|
struct val *vp;
|
|
|
|
vp = (struct val *) malloc (sizeof (*vp));
|
|
if (vp == NULL) {
|
|
errx(ERR_EXIT, "malloc() failed");
|
|
}
|
|
|
|
vp->type = integer;
|
|
vp->u.i = i;
|
|
return vp;
|
|
}
|
|
|
|
struct val *
|
|
make_str(const char *s)
|
|
{
|
|
struct val *vp;
|
|
char *ep;
|
|
|
|
vp = (struct val *) malloc (sizeof (*vp));
|
|
if (vp == NULL || ((vp->u.s = strdup (s)) == NULL)) {
|
|
errx(ERR_EXIT, "malloc() failed");
|
|
}
|
|
|
|
/*
|
|
* Previously we tried to scan the string to see if it ``looked like''
|
|
* an integer (erroneously, as it happened). Let strtoimax() do the
|
|
* dirty work. We could cache the value, except that we are using
|
|
* a union and need to preserve the original string form until we
|
|
* are certain that it is not needed.
|
|
*
|
|
* IEEE Std.1003.1-2001 says:
|
|
* /integer/ An argument consisting only of an (optional) unary minus
|
|
* followed by digits.
|
|
*
|
|
* This means that arguments which consist of digits followed by
|
|
* non-digits MUST NOT be considered integers. strtoimax() will
|
|
* figure this out for us.
|
|
*/
|
|
if (eflag)
|
|
(void)strtoimax(s, &ep, 10);
|
|
else
|
|
(void)strtol(s, &ep, 10);
|
|
|
|
if (*ep != '\0')
|
|
vp->type = string;
|
|
else
|
|
vp->type = numeric_string;
|
|
|
|
return vp;
|
|
}
|
|
|
|
|
|
void
|
|
free_value(struct val *vp)
|
|
{
|
|
if (vp->type == string || vp->type == numeric_string)
|
|
free (vp->u.s);
|
|
}
|
|
|
|
|
|
intmax_t
|
|
to_integer(struct val *vp)
|
|
{
|
|
intmax_t i;
|
|
|
|
if (vp->type == integer)
|
|
return 1;
|
|
|
|
if (vp->type == string)
|
|
return 0;
|
|
|
|
/* vp->type == numeric_string, make it numeric */
|
|
errno = 0;
|
|
if (eflag) {
|
|
i = strtoimax(vp->u.s, (char **)NULL, 10);
|
|
if (errno == ERANGE)
|
|
err(ERR_EXIT, NULL);
|
|
} else {
|
|
i = strtol(vp->u.s, (char **)NULL, 10);
|
|
}
|
|
|
|
free (vp->u.s);
|
|
vp->u.i = i;
|
|
vp->type = integer;
|
|
return 1;
|
|
}
|
|
|
|
void
|
|
to_string(struct val *vp)
|
|
{
|
|
char *tmp;
|
|
|
|
if (vp->type == string || vp->type == numeric_string)
|
|
return;
|
|
|
|
/*
|
|
* log_10(x) ~= 0.3 * log_2(x). Rounding up gives the number
|
|
* of digits; add one each for the sign and terminating null
|
|
* character, respectively.
|
|
*/
|
|
#define NDIGITS(x) (3 * (sizeof(x) * CHAR_BIT) / 10 + 1 + 1 + 1)
|
|
tmp = malloc(NDIGITS(vp->u.i));
|
|
if (tmp == NULL)
|
|
errx(ERR_EXIT, "malloc() failed");
|
|
|
|
sprintf(tmp, "%jd", vp->u.i);
|
|
vp->type = string;
|
|
vp->u.s = tmp;
|
|
}
|
|
|
|
|
|
int
|
|
isstring(struct val *vp)
|
|
{
|
|
/* only TRUE if this string is not a valid integer */
|
|
return (vp->type == string);
|
|
}
|
|
|
|
|
|
int
|
|
yylex(void)
|
|
{
|
|
char *p;
|
|
|
|
if (*av == NULL)
|
|
return (0);
|
|
|
|
p = *av++;
|
|
|
|
if (strlen (p) == 1) {
|
|
if (strchr ("|&=<>+-*/%:()", *p))
|
|
return (*p);
|
|
} else if (strlen (p) == 2 && p[1] == '=') {
|
|
switch (*p) {
|
|
case '>': return (GE);
|
|
case '<': return (LE);
|
|
case '!': return (NE);
|
|
}
|
|
}
|
|
|
|
yylval.val = make_str (p);
|
|
return (TOKEN);
|
|
}
|
|
|
|
int
|
|
is_zero_or_null(struct val *vp)
|
|
{
|
|
if (vp->type == integer) {
|
|
return (vp->u.i == 0);
|
|
} else {
|
|
return (*vp->u.s == 0 || (to_integer (vp) && vp->u.i == 0));
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
int c;
|
|
|
|
setlocale (LC_ALL, "");
|
|
if (getenv("EXPR_COMPAT") != NULL) {
|
|
av = argv + 1;
|
|
eflag = 1;
|
|
} else {
|
|
while ((c = getopt(argc, argv, "e")) != -1)
|
|
switch (c) {
|
|
case 'e':
|
|
eflag = 1;
|
|
break;
|
|
|
|
default:
|
|
fprintf(stderr,
|
|
"usage: expr [-e] expression\n");
|
|
exit(ERR_EXIT);
|
|
}
|
|
av = argv + optind;
|
|
}
|
|
|
|
yyparse();
|
|
|
|
if (result->type == integer)
|
|
printf("%jd\n", result->u.i);
|
|
else
|
|
printf("%s\n", result->u.s);
|
|
|
|
return (is_zero_or_null(result));
|
|
}
|
|
|
|
int
|
|
yyerror(const char *s __unused)
|
|
{
|
|
errx(ERR_EXIT, "syntax error");
|
|
}
|
|
|
|
|
|
struct val *
|
|
op_or(struct val *a, struct val *b)
|
|
{
|
|
if (is_zero_or_null (a)) {
|
|
free_value (a);
|
|
return (b);
|
|
} else {
|
|
free_value (b);
|
|
return (a);
|
|
}
|
|
}
|
|
|
|
struct val *
|
|
op_and(struct val *a, struct val *b)
|
|
{
|
|
if (is_zero_or_null (a) || is_zero_or_null (b)) {
|
|
free_value (a);
|
|
free_value (b);
|
|
return (make_integer ((intmax_t)0));
|
|
} else {
|
|
free_value (b);
|
|
return (a);
|
|
}
|
|
}
|
|
|
|
struct val *
|
|
op_eq(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (isstring (a) || isstring (b)) {
|
|
to_string (a);
|
|
to_string (b);
|
|
r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) == 0));
|
|
} else {
|
|
(void)to_integer(a);
|
|
(void)to_integer(b);
|
|
r = make_integer ((intmax_t)(a->u.i == b->u.i));
|
|
}
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
struct val *
|
|
op_gt(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (isstring (a) || isstring (b)) {
|
|
to_string (a);
|
|
to_string (b);
|
|
r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) > 0));
|
|
} else {
|
|
(void)to_integer(a);
|
|
(void)to_integer(b);
|
|
r = make_integer ((intmax_t)(a->u.i > b->u.i));
|
|
}
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
struct val *
|
|
op_lt(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (isstring (a) || isstring (b)) {
|
|
to_string (a);
|
|
to_string (b);
|
|
r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) < 0));
|
|
} else {
|
|
(void)to_integer(a);
|
|
(void)to_integer(b);
|
|
r = make_integer ((intmax_t)(a->u.i < b->u.i));
|
|
}
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
struct val *
|
|
op_ge(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (isstring (a) || isstring (b)) {
|
|
to_string (a);
|
|
to_string (b);
|
|
r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) >= 0));
|
|
} else {
|
|
(void)to_integer(a);
|
|
(void)to_integer(b);
|
|
r = make_integer ((intmax_t)(a->u.i >= b->u.i));
|
|
}
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
struct val *
|
|
op_le(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (isstring (a) || isstring (b)) {
|
|
to_string (a);
|
|
to_string (b);
|
|
r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) <= 0));
|
|
} else {
|
|
(void)to_integer(a);
|
|
(void)to_integer(b);
|
|
r = make_integer ((intmax_t)(a->u.i <= b->u.i));
|
|
}
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
struct val *
|
|
op_ne(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (isstring (a) || isstring (b)) {
|
|
to_string (a);
|
|
to_string (b);
|
|
r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) != 0));
|
|
} else {
|
|
(void)to_integer(a);
|
|
(void)to_integer(b);
|
|
r = make_integer ((intmax_t)(a->u.i != b->u.i));
|
|
}
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
int
|
|
chk_plus(intmax_t a, intmax_t b, intmax_t r)
|
|
{
|
|
|
|
/* sum of two positive numbers must be positive */
|
|
if (a > 0 && b > 0 && r <= 0)
|
|
return 1;
|
|
/* sum of two negative numbers must be negative */
|
|
if (a < 0 && b < 0 && r >= 0)
|
|
return 1;
|
|
/* all other cases are OK */
|
|
return 0;
|
|
}
|
|
|
|
struct val *
|
|
op_plus(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (!to_integer(a) || !to_integer(b)) {
|
|
errx(ERR_EXIT, "non-numeric argument");
|
|
}
|
|
|
|
if (eflag) {
|
|
r = make_integer(a->u.i + b->u.i);
|
|
if (chk_plus(a->u.i, b->u.i, r->u.i)) {
|
|
errx(ERR_EXIT, "overflow");
|
|
}
|
|
} else
|
|
r = make_integer((long)a->u.i + (long)b->u.i);
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
int
|
|
chk_minus(intmax_t a, intmax_t b, intmax_t r)
|
|
{
|
|
|
|
/* special case subtraction of INTMAX_MIN */
|
|
if (b == INTMAX_MIN) {
|
|
if (a >= 0)
|
|
return 1;
|
|
else
|
|
return 0;
|
|
}
|
|
/* this is allowed for b != INTMAX_MIN */
|
|
return chk_plus (a, -b, r);
|
|
}
|
|
|
|
struct val *
|
|
op_minus(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (!to_integer(a) || !to_integer(b)) {
|
|
errx(ERR_EXIT, "non-numeric argument");
|
|
}
|
|
|
|
if (eflag) {
|
|
r = make_integer(a->u.i - b->u.i);
|
|
if (chk_minus(a->u.i, b->u.i, r->u.i)) {
|
|
errx(ERR_EXIT, "overflow");
|
|
}
|
|
} else
|
|
r = make_integer((long)a->u.i - (long)b->u.i);
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
int
|
|
chk_times(intmax_t a, intmax_t b, intmax_t r)
|
|
{
|
|
/* special case: first operand is 0, no overflow possible */
|
|
if (a == 0)
|
|
return 0;
|
|
/* cerify that result of division matches second operand */
|
|
if (r / a != b)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
struct val *
|
|
op_times(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (!to_integer(a) || !to_integer(b)) {
|
|
errx(ERR_EXIT, "non-numeric argument");
|
|
}
|
|
|
|
if (eflag) {
|
|
r = make_integer(a->u.i * b->u.i);
|
|
if (chk_times(a->u.i, b->u.i, r->u.i)) {
|
|
errx(ERR_EXIT, "overflow");
|
|
}
|
|
} else
|
|
r = make_integer((long)a->u.i * (long)b->u.i);
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return (r);
|
|
}
|
|
|
|
int
|
|
chk_div(intmax_t a, intmax_t b)
|
|
{
|
|
/* div by zero has been taken care of before */
|
|
/* only INTMAX_MIN / -1 causes overflow */
|
|
if (a == INTMAX_MIN && b == -1)
|
|
return 1;
|
|
/* everything else is OK */
|
|
return 0;
|
|
}
|
|
|
|
struct val *
|
|
op_div(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (!to_integer(a) || !to_integer(b)) {
|
|
errx(ERR_EXIT, "non-numeric argument");
|
|
}
|
|
|
|
if (b->u.i == 0) {
|
|
errx(ERR_EXIT, "division by zero");
|
|
}
|
|
|
|
if (eflag) {
|
|
r = make_integer(a->u.i / b->u.i);
|
|
if (chk_div(a->u.i, b->u.i)) {
|
|
errx(ERR_EXIT, "overflow");
|
|
}
|
|
} else
|
|
r = make_integer((long)a->u.i / (long)b->u.i);
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
struct val *
|
|
op_rem(struct val *a, struct val *b)
|
|
{
|
|
struct val *r;
|
|
|
|
if (!to_integer(a) || !to_integer(b)) {
|
|
errx(ERR_EXIT, "non-numeric argument");
|
|
}
|
|
|
|
if (b->u.i == 0) {
|
|
errx(ERR_EXIT, "division by zero");
|
|
}
|
|
|
|
if (eflag)
|
|
r = make_integer(a->u.i % b->u.i);
|
|
/* chk_rem necessary ??? */
|
|
else
|
|
r = make_integer((long)a->u.i % (long)b->u.i);
|
|
|
|
free_value (a);
|
|
free_value (b);
|
|
return r;
|
|
}
|
|
|
|
struct val *
|
|
op_colon(struct val *a, struct val *b)
|
|
{
|
|
regex_t rp;
|
|
regmatch_t rm[2];
|
|
char errbuf[256];
|
|
int eval;
|
|
struct val *v;
|
|
|
|
/* coerce to both arguments to strings */
|
|
to_string(a);
|
|
to_string(b);
|
|
|
|
/* compile regular expression */
|
|
if ((eval = regcomp (&rp, b->u.s, 0)) != 0) {
|
|
regerror (eval, &rp, errbuf, sizeof(errbuf));
|
|
errx(ERR_EXIT, "%s", errbuf);
|
|
}
|
|
|
|
/* compare string against pattern */
|
|
/* remember that patterns are anchored to the beginning of the line */
|
|
if (regexec(&rp, a->u.s, (size_t)2, rm, 0) == 0 && rm[0].rm_so == 0) {
|
|
if (rm[1].rm_so >= 0) {
|
|
*(a->u.s + rm[1].rm_eo) = '\0';
|
|
v = make_str (a->u.s + rm[1].rm_so);
|
|
|
|
} else {
|
|
v = make_integer ((intmax_t)(rm[0].rm_eo - rm[0].rm_so));
|
|
}
|
|
} else {
|
|
if (rp.re_nsub == 0) {
|
|
v = make_integer ((intmax_t)0);
|
|
} else {
|
|
v = make_str ("");
|
|
}
|
|
}
|
|
|
|
/* free arguments and pattern buffer */
|
|
free_value (a);
|
|
free_value (b);
|
|
regfree (&rp);
|
|
|
|
return v;
|
|
}
|