cmd/basename/basename.c

	basename.c revision 55381082fdea0647bb5d44ceeed7d5af386f30d2
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef XPG4
#include <unistd.h>
#include <regex.h>
#include <libintl.h>
#endif

int
main(int argc, char **argv)
{
    char    *p;
    char    *string;
    char    *suffix;
#ifndef XPG4
    int r;
    char    suf_buf[256];
    char    *suf_pat;
    size_t  suf_len;
    regex_t reg;
    regmatch_t  pmatch[2];
#endif

    /*
     * For better performance, defer the setlocale()/textdomain()
     * calls until they get really required.
     */
#if !defined(TEXT_DOMAIN)
#define TEXT_DOMAIN "SYS_TEST"
#endif
    if (argc == 1) {
        (void) puts(".");
        return (0);
    }

#ifdef  XPG4
    if (strcmp(argv[1], "--") == 0) {
        argv++;
        argc--;
        if (argc == 1) {
            (void) puts(".");
            return (0);
        }
    }
#endif
    if (argc > 3) {
        (void) setlocale(LC_ALL, "");
        (void) textdomain(TEXT_DOMAIN);
        (void) fputs(gettext("Usage: basename string [ suffix ]\n"),
            stderr);
        return (1);
    }

    string = argv[1];
    suffix = (argc == 2) ? NULL : argv[2];

    if (*string == '\0') {
        (void) puts(".");
        return (0);
    }

    /* remove trailing slashes */
    p = string + strlen(string) - 1;
    while (p >= string && *p == '/')
        *p-- = '\0';

    if (*string == '\0') {
        (void) puts("/");
        return (0);
    }

    /* skip to one past last slash */
    if ((p = strrchr(string, '/')) != NULL)
        string = p + 1;

    if (suffix == NULL) {
        (void) puts(string);
        return (0);
    }

#ifdef  XPG4
    /*
     * if a suffix is present and is not the same as the remaining
     * string and is identical to the last characters in the remaining
     * string, remove those characters from the string.
     */
    if (strcmp(string, suffix) != 0) {
        p = string + strlen(string) - strlen(suffix);
        if (strcmp(p, suffix) == 0)
            *p = '\0';
    }
    (void) puts(string);
    return (0);
#else
    (void) setlocale(LC_ALL, "");
    (void) textdomain(TEXT_DOMAIN);

    suf_len = 6 + strlen(suffix) + 1 + 1; /* \(.*\)suffix$ */
    if (suf_len > sizeof (suf_buf)) {
        suf_pat = malloc(suf_len);
        if (suf_pat == NULL) {
            (void) fputs("malloc failed\n", stderr);
            return (1);
        }
    } else {
        suf_pat = suf_buf;
    }
    (void) strcpy(suf_pat, "\\(.*\\)");
    (void) strcpy(suf_pat + 6, suffix);
    *(suf_pat + suf_len - 1 - 1) = '$';
    *(suf_pat + suf_len - 1) = '\0';

    r = regcomp(&reg, suf_pat, 0);
    if (r != 0) {
        (void) fprintf(stderr,
            "Internal error: regcomp failed for \"%s\"\n",
            suf_pat);
        return (1);
    }
    r = regexec(&reg, string, 2, pmatch, 0);
    if (r == 0) {
        if (pmatch[0].rm_so == (regoff_t)-1 ||
            pmatch[1].rm_so == (regoff_t)-1 ||
            pmatch[1].rm_so != 0) {
            (void) fprintf(stderr, "Internal error: regexec did "
                "not set sub-expression for:\n");
            (void) fprintf(stderr, "path: \"%s\"\n", string);
            (void) fprintf(stderr, "pattern: \"%s\"", suf_pat);
            return (1);
        }
        if (pmatch[1].rm_so == pmatch[1].rm_eo) {
            /* a null string matched */
            (void) printf("%s\n", string);
            return (0);
        }
        string[pmatch[1].rm_eo] = '\0';
    }
    (void) puts(string);
    return (0);
#endif
}