/*

 * Copyright 2004-2023 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

/*

 * This file is dual-licensed and is also available under the following

 * terms:

 *

 * Copyright (c) 2004, 2018, Richard Levitte <richard@levitte.org>

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include <stddef.h>

#include <stdlib.h>

#include <limits.h>

#include <string.h>

#include <sys/types.h>

#include <dirent.h>

#include <errno.h>

#ifndef LPDIR_H

# include "LPdir.h"

#endif

#ifdef __VMS

# include <ctype.h>

#endif

/*

 * The POSIX macro for the maximum number of characters in a file path is

 * NAME_MAX.  However, some operating systems use PATH_MAX instead.

 * Therefore, it seems natural to first check for PATH_MAX and use that, and

 * if it doesn't exist, use NAME_MAX.

 */

#if defined(PATH_MAX)

# define LP_ENTRY_SIZE PATH_MAX

#elif defined(NAME_MAX)

# define LP_ENTRY_SIZE NAME_MAX

#endif

/*

 * Of course, there's the possibility that neither PATH_MAX nor NAME_MAX

 * exist.  It's also possible that NAME_MAX exists but is define to a very

 * small value (HP-UX offers 14), so we need to check if we got a result, and

 * if it meets a minimum standard, and create or change it if not.

 */

#if !defined(LP_ENTRY_SIZE) || LP_ENTRY_SIZE<255

# undef LP_ENTRY_SIZE

# define LP_ENTRY_SIZE 255

#endif

struct LP_dir_context_st {

    DIR *dir;

    char entry_name[LP_ENTRY_SIZE + 1];

#ifdef __VMS

    int expect_file_generations;

    char previous_entry_name[LP_ENTRY_SIZE + 1];

#endif

};

const char *LP_find_file(LP_DIR_CTX **ctx, const char *directory)

{

    struct dirent *direntry = NULL;

    if (ctx == NULL || directory == NULL) {

        errno = EINVAL;

        return 0;

    }

    errno = 0;

    if (*ctx == NULL) {

        *ctx = malloc(sizeof(**ctx));

        if (*ctx == NULL) {

            errno = ENOMEM;

            return 0;

        }

        memset(*ctx, 0, sizeof(**ctx));

#ifdef __VMS

        {

            char c = directory[strlen(directory) - 1];

            if (c == ']' || c == '>' || c == ':')

                (*ctx)->expect_file_generations = 1;

        }

#endif

        (*ctx)->dir = opendir(directory);

        if ((*ctx)->dir == NULL) {

            int save_errno = errno; /* Probably not needed, but I'm paranoid */

            free(*ctx);

            *ctx = NULL;

            errno = save_errno;

            return 0;

        }

    }

#ifdef __VMS

    strncpy((*ctx)->previous_entry_name, (*ctx)->entry_name,

            sizeof((*ctx)->previous_entry_name));

 again:

#endif

    direntry = readdir((*ctx)->dir);

    if (direntry == NULL) {

        return 0;

    }

    OPENSSL_strlcpy((*ctx)->entry_name, direntry->d_name,

                    sizeof((*ctx)->entry_name));

#ifdef __VMS

    if ((*ctx)->expect_file_generations) {

        char *p = (*ctx)->entry_name + strlen((*ctx)->entry_name);

        while (p > (*ctx)->entry_name && isdigit((unsigned char)p[-1]))

            p--;

        if (p > (*ctx)->entry_name && p[-1] == ';')

            p[-1] = '\0';

        if (OPENSSL_strcasecmp((*ctx)->entry_name,

                               (*ctx)->previous_entry_name) == 0)

            goto again;

    }

#endif

    return (*ctx)->entry_name;

}

int LP_find_file_end(LP_DIR_CTX **ctx)

{

    if (ctx != NULL && *ctx != NULL) {

        int ret = closedir((*ctx)->dir);

        free(*ctx);

        switch (ret) {

        case 0:

            return 1;

        case -1:

            return 0;

        default:

            break;

        }

    }

    errno = EINVAL;

    return 0;

}