crypto/LPdir_unix.c

   1 /*
   2  * Copyright 2004-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /*
  11  * This file is dual-licensed and is also available under the following
  12  * terms:
  13  *
  14  * Copyright (c) 2004, Richard Levitte <richard@levitte.org>
  15  * All rights reserved.
  16  *
  17  * Redistribution and use in source and binary forms, with or without
  18  * modification, are permitted provided that the following conditions
  19  * are met:
  20  * 1. Redistributions of source code must retain the above copyright
  21  *    notice, this list of conditions and the following disclaimer.
  22  * 2. Redistributions in binary form must reproduce the above copyright
  23  *    notice, this list of conditions and the following disclaimer in the
  24  *    documentation and/or other materials provided with the distribution.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  28  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  29  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  30  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  31  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  32  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  33  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  36  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 #include <stddef.h>
  40 #include <stdlib.h>
  41 #include <limits.h>
  42 #include <string.h>
  43 #include <sys/types.h>
  44 #include <dirent.h>
  45 #include <errno.h>
  46 #ifndef LPDIR_H
  47 # include "LPdir.h"
  48 #endif
  49
  50 /*
  51  * The POSIXly macro for the maximum number of characters in a file path is
  52  * NAME_MAX.  However, some operating systems use PATH_MAX instead.
  53  * Therefore, it seems natural to first check for PATH_MAX and use that, and
  54  * if it doesn't exist, use NAME_MAX.
  55  */
  56 #if defined(PATH_MAX)
  57 # define LP_ENTRY_SIZE PATH_MAX
  58 #elif defined(NAME_MAX)
  59 # define LP_ENTRY_SIZE NAME_MAX
  60 #endif
  61
  62 /*
  63  * Of course, there's the possibility that neither PATH_MAX nor NAME_MAX
  64  * exist.  It's also possible that NAME_MAX exists but is define to a very
  65  * small value (HP-UX offers 14), so we need to check if we got a result, and
  66  * if it meets a minimum standard, and create or change it if not.
  67  */
  68 #if !defined(LP_ENTRY_SIZE) || LP_ENTRY_SIZE<255
  69 # undef LP_ENTRY_SIZE
  70 # define LP_ENTRY_SIZE 255
  71 #endif
  72
  73 struct LP_dir_context_st {
  74     DIR *dir;
  75     char entry_name[LP_ENTRY_SIZE + 1];
  76 };
  77
  78 const char *LP_find_file(LP_DIR_CTX **ctx, const char *directory)
  79 {
  80     struct dirent *direntry = NULL;
  81
  82     if (ctx == NULL || directory == NULL) {
  83         errno = EINVAL;
  84         return 0;
  85     }
  86
  87     errno = 0;
  88     if (*ctx == NULL) {
  89         *ctx = malloc(sizeof(**ctx));
  90         if (*ctx == NULL) {
  91             errno = ENOMEM;
  92             return 0;
  93         }
  94         memset(*ctx, 0, sizeof(**ctx));
  95
  96         (*ctx)->dir = opendir(directory);
  97         if ((*ctx)->dir == NULL) {
  98             int save_errno = errno; /* Probably not needed, but I'm paranoid */
  99             free(*ctx);
 100             *ctx = NULL;
 101             errno = save_errno;
 102             return 0;
 103         }
 104     }
 105
 106     direntry = readdir((*ctx)->dir);
 107     if (direntry == NULL) {
 108         return 0;
 109     }
 110
 111     strncpy((*ctx)->entry_name, direntry->d_name,
 112             sizeof((*ctx)->entry_name) - 1);
 113     (*ctx)->entry_name[sizeof((*ctx)->entry_name) - 1] = '\0';
 114     return (*ctx)->entry_name;
 115 }
 116
 117 int LP_find_file_end(LP_DIR_CTX **ctx)
 118 {
 119     if (ctx != NULL && *ctx != NULL) {
 120         int ret = closedir((*ctx)->dir);
 121
 122         free(*ctx);
 123         switch (ret) {
 124         case 0:
 125             return 1;
 126         case -1:
 127             return 0;
 128         default:
 129             break;
 130         }
 131     }
 132     errno = EINVAL;
 133     return 0;
 134 }