+++ /dev/null
-/* $NetBSD: expr.c,v 1.9 1998/07/28 11:41:48 mycroft Exp $ */
-
-/*
- * Written by J.T. Conklin <jtc@netbsd.org>.
- * Public domain.
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <locale.h>
-#include <ctype.h>
-#include <regex.h>
-#include <err.h>
-
-
-enum token {
- OR, AND, EQ, LT, GT, ADD, SUB, MUL, DIV, MOD, MATCH, RP, LP,
- NE, LE, GE, OPERAND, EOI
-};
-
-struct val {
- enum {
- integer,
- string
- } type;
-
- union {
- char *s;
- int64_t i;
- } u;
-};
-
-enum token token;
-struct val *tokval;
-char **av;
-
-struct val *make_int __P((int64_t));
-struct val *make_str __P((char *));
-void free_value __P((struct val *));
-int is_integer __P((struct val *, int64_t *));
-int to_integer __P((struct val *));
-void to_string __P((struct val *));
-int is_null __P((struct val *));
-int is_zero_or_null __P((struct val *));
-void nexttoken __P((void));
-void error __P((void)) __attribute__((__noreturn__));
-struct val *eval6 __P((void));
-struct val *eval5 __P((void));
-struct val *eval4 __P((void));
-struct val *eval3 __P((void));
-struct val *eval2 __P((void));
-struct val *eval1 __P((void));
-struct val *eval0 __P((void));
-int main __P((int, char **));
-
-
-struct val *
-make_int(i)
- int64_t i;
-{
- struct val *vp;
-
- vp = (struct val *) malloc(sizeof(*vp));
- if (vp == NULL) {
- err(2, "%s", "");
- }
- vp->type = integer;
- vp->u.i = i;
- return vp;
-}
-
-
-struct val *
-make_str(s)
- char *s;
-{
- struct val *vp;
-
- vp = (struct val *) malloc(sizeof(*vp));
- if (vp == NULL || ((vp->u.s = strdup(s)) == NULL)) {
- err(2, "%s", "");
- }
- vp->type = string;
- return vp;
-}
-
-
-void
-free_value(vp)
- struct val *vp;
-{
- if (vp->type == string)
- free(vp->u.s);
- free(vp);
-}
-
-
-/* determine if vp is an integer; if so, return it's value in *r */
-int
-is_integer(vp, r)
- struct val *vp;
- int64_t *r;
-{
- char *s;
- int neg;
- int64_t i;
-
- if (vp->type == integer) {
- *r = vp->u.i;
- return 1;
- }
-
- /*
- * POSIX.2 defines an "integer" as an optional unary minus
- * followed by digits.
- */
- s = vp->u.s;
- i = 0;
-
- neg = (*s == '-');
- if (neg) {
- s++;
- /* the optional unary minus *must* be followed by digits to
- * be considered an integer. A '-' alone is not an integer.
- */
- if(!*s)
- return 0;
- }
-
- while (*s) {
- if (!isdigit(*s))
- return 0;
-
- i *= 10;
- i += *s - '0';
-
- s++;
- }
-
- if (neg)
- i *= -1;
-
- *r = i;
- return 1;
-}
-
-
-/* coerce to vp to an integer */
-int
-to_integer(vp)
- struct val *vp;
-{
- int64_t r;
-
- if (vp->type == integer)
- return 1;
-
- if (is_integer(vp, &r)) {
- free(vp->u.s);
- vp->u.i = r;
- vp->type = integer;
- return 1;
- }
-
- return 0;
-}
-
-
-/* coerce to vp to an string */
-void
-to_string(vp)
- struct val *vp;
-{
- char *tmp;
-
- if (vp->type == string)
- return;
-
- tmp = malloc(100);
- if (tmp == NULL) {
- err(2, "%s", "");
- }
- (void)snprintf(tmp, 100, "%lld", vp->u.i);
- vp->type = string;
- vp->u.s = tmp;
-}
-
-int is_null(vp)
- struct val *vp;
-{
- if ((vp->type != integer) && (*vp->u.s == 0))
- return 1;
- return 0;
-}
-
-int
-is_zero_or_null(vp)
- 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 */
-}
-
-void
-nexttoken()
-{
- char *p;
-
- if ((p = *av) == NULL) {
- token = EOI;
- return;
- }
- av++;
-
- if (p[0] != '\0') {
- if (p[1] == '\0') {
- const char *x = "|&=<>+-*/%:()";
- char *i; /* index */
-
- if ((i = strchr(x, *p)) != NULL) {
- token = i - x;
- return;
- }
- } else if (p[1] == '=' && p[2] == '\0') {
- switch (*p) {
- case '<':
- token = LE;
- return;
- case '>':
- token = GE;
- return;
- case '!':
- token = NE;
- return;
- }
- }
- }
- tokval = make_str(p);
- token = OPERAND;
- return;
-}
-
-void
-error()
-{
- errx(2, "syntax error");
- /* NOTREACHED */
-}
-
-struct val *
-eval6()
-{
- struct val *v;
-
- if (token == OPERAND) {
- nexttoken();
- return tokval;
-
- } else if (token == RP) {
- nexttoken();
- v = eval0();
-
- if (token != LP)
- error();
-
- nexttoken();
- return v;
- } else {
-
- switch (token) {
- case DIV:
- nexttoken();
- tokval = make_str("/");
- break;
- case MUL:
- nexttoken();
- tokval = make_str("*");
- break;
- case OR:
- nexttoken();
- tokval = make_str("|");
- break;
- case AND:
- nexttoken();
- tokval = make_str("&");
- break;
- case EQ:
- nexttoken();
- tokval = make_str("=");
- break;
- case LT:
- nexttoken();
- tokval = make_str("<");
- break;
- case GT:
- nexttoken();
- tokval = make_str(">");
- break;
- case ADD:
- nexttoken();
- tokval = make_str("+");
- break;
- case SUB:
- nexttoken();
- tokval = make_str("-");
- break;
- case MOD:
- nexttoken();
- tokval = make_str("%");
- break;
- case NE:
- nexttoken();
- tokval = make_str("!=");
- break;
- case LE:
- nexttoken();
- tokval = make_str("<=");
- break;
- case MATCH:
- nexttoken();
- tokval = make_str(":");
- break;
- case GE:
- nexttoken();
- tokval = make_str(">=");
- break;
- case EOI:
- error();
- }
- return tokval;
- }
- /* NOTREACHED */
-}
-
-/* Parse and evaluate match (regex) expressions */
-struct val *
-eval5()
-{
- regex_t rp;
- regmatch_t rm[2];
- char errbuf[256];
- int eval;
- struct val *l, *r;
- struct val *v;
-
- l = eval6();
- while (token == MATCH) {
- nexttoken();
- r = eval6();
-
- /* coerce to both arguments to strings */
- to_string(l);
- to_string(r);
-
- /* compile regular expression */
- if ((eval = regcomp(&rp, r->u.s, 0)) != 0) {
- (void)regerror(eval, &rp, errbuf, sizeof(errbuf));
- errx(2, "%s", errbuf);
- }
-
- /* compare string against pattern -- remember that patterns
- are anchored to the beginning of the line */
- if (regexec(&rp, l->u.s, 2, rm, 0) == 0 && rm[0].rm_so == 0) {
- if (rm[1].rm_so >= 0) {
- *(l->u.s + rm[1].rm_eo) = '\0';
- v = make_str(l->u.s + rm[1].rm_so);
-
- } else {
- v = make_int((int)(rm[0].rm_eo - rm[0].rm_so));
- }
- } else {
- if (rp.re_nsub == 0) {
- v = make_int(0);
- } else {
- v = make_str("");
- }
- }
-
- /* free arguments and pattern buffer */
- free_value(l);
- free_value(r);
- regfree(&rp);
-
- l = v;
- }
-
- return l;
-}
-
-/* Parse and evaluate multiplication and division expressions */
-struct val *
-eval4()
-{
- struct val *l, *r;
- enum token op;
-
- l = eval5();
- while ((op = token) == MUL || op == DIV || op == MOD) {
- nexttoken();
- r = eval5();
-
- if (!to_integer(l) || !to_integer(r)) {
- errx(2, "non-numeric argument");
- }
-
- if (op == MUL) {
- l->u.i *= r->u.i;
- } else {
- if (r->u.i == 0) {
- errx(2, "division by zero");
- }
- if (op == DIV) {
- l->u.i /= r->u.i;
- } else {
- l->u.i %= r->u.i;
- }
- }
-
- free_value(r);
- }
-
- return l;
-}
-
-/* Parse and evaluate addition and subtraction expressions */
-struct val *
-eval3()
-{
- struct val *l, *r;
- enum token op;
-
- l = eval4();
- while ((op = token) == ADD || op == SUB) {
- nexttoken();
- r = eval4();
-
- if (!to_integer(l) || !to_integer(r)) {
- errx(2, "non-numeric argument");
- }
-
- if (op == ADD) {
- l->u.i += r->u.i;
- } else {
- l->u.i -= r->u.i;
- }
-
- free_value(r);
- }
-
- return l;
-}
-
-/* Parse and evaluate comparison expressions */
-struct val *
-eval2()
-{
- struct val *l, *r;
- enum token op;
- int v = 0; /* pacify gcc */
- int64_t li, ri;
-
- l = eval3();
- while ((op = token) == EQ || op == NE || op == LT || op == GT || op == LE || op == GE) {
- nexttoken();
- r = eval3();
-
- if (is_integer(l, &li) && is_integer(r, &ri)) {
- switch (op) {
- case GT:
- v = (li > ri);
- break;
- case GE:
- v = (li >= ri);
- break;
- case LT:
- v = (li < ri);
- break;
- case LE:
- v = (li <= ri);
- break;
- case EQ:
- v = (li == ri);
- break;
- case NE:
- v = (li != ri);
- break;
- case MOD:
- case EOI:
- case OPERAND:
- case LP:
- case RP:
- case MATCH:
- case DIV:
- case MUL:
- case SUB:
- case ADD:
- case AND:
- case OR:
- /* Can't happen */
- abort();
- break;
- }
- } else {
- to_string(l);
- to_string(r);
-
- switch (op) {
- case GT:
- v = (strcoll(l->u.s, r->u.s) > 0);
- break;
- case GE:
- v = (strcoll(l->u.s, r->u.s) >= 0);
- break;
- case LT:
- v = (strcoll(l->u.s, r->u.s) < 0);
- break;
- case LE:
- v = (strcoll(l->u.s, r->u.s) <= 0);
- break;
- case EQ:
- v = (strcoll(l->u.s, r->u.s) == 0);
- break;
- case NE:
- v = (strcoll(l->u.s, r->u.s) != 0);
- break;
- case MUL:
- case SUB:
- case ADD:
- case AND:
- case OR:
- case DIV:
- case OPERAND:
- case EOI:
- case MOD:
- case RP:
- case MATCH:
- case LP:
- /* Can't happen */
- abort();
- break;
- }
- }
-
- free_value(l);
- free_value(r);
- l = make_int(v);
- }
-
- return l;
-}
-
-/* Parse and evaluate & expressions */
-struct val *
-eval1()
-{
- struct val *l, *r;
-
- l = eval2();
- while (token == AND) {
- nexttoken();
- r = eval2();
-
- if (is_zero_or_null(l) || is_zero_or_null(r)) {
- free_value(l);
- free_value(r);
- l = make_int(0);
- } else {
- free_value(r);
- }
- }
-
- return l;
-}
-
-/* Parse and evaluate | expressions */
-struct val *
-eval0()
-{
- struct val *l, *r;
-
- l = eval1();
- while (token == OR) {
- nexttoken();
- r = eval1();
-
- if (is_zero_or_null(l)) {
- free_value(l);
- l = r;
- if( is_null(r) ) {
- free_value(r);
- l = make_int(0);
- }
- } else {
- free_value(r);
- }
- }
-
- return l;
-}
-
-
-int
-main(argc, argv)
- int argc;
- char **argv;
-{
- struct val *vp;
-
- (void) setlocale(LC_ALL, "");
- av = argv + 1;
- if (*av && !strcmp(*av, "--"))
- av++;
- nexttoken();
- vp = eval0();
-
- if (token != EOI)
- error();
- if (vp->type == string && vp->u.s[0])
- to_integer(vp); /* -0 is not a string */
- if (vp->type == integer)
- (void)printf("%lld\n", vp->u.i);
- else
- (void)printf("%s\n", vp->u.s);
-
- exit(is_zero_or_null(vp));
- /* NOTREACHED */
-}
projects / apple / shell_cmds.git / blobdiff