release/src/router/openssl/crypto/LPdir_unix.c

   1 /* $LP: LPlib/source/LPdir_unix.c,v 1.11 2004/09/23 22:07:22 _cvs_levitte Exp $ */
   2 /*
   3  * Copyright (c) 2004, Richard Levitte <richard@levitte.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  18  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  19  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  20  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  21  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  25  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <stddef.h>
  29 #include <stdlib.h>
  30 #include <limits.h>
  31 #include <string.h>
  32 #include <sys/types.h>
  33 #include <dirent.h>
  34 #include <errno.h>
  35 #ifndef LPDIR_H
  36 #include "LPdir.h"
  37 #endif
  38
  39 /* The POSIXly macro for the maximum number of characters in a file path
  40    is NAME_MAX.  However, some operating systems use PATH_MAX instead.
  41    Therefore, it seems natural to first check for PATH_MAX and use that,
  42    and if it doesn't exist, use NAME_MAX. */
  43 #if defined(PATH_MAX)
  44 # define LP_ENTRY_SIZE PATH_MAX
  45 #elif defined(NAME_MAX)
  46 # define LP_ENTRY_SIZE NAME_MAX
  47 #endif
  48
  49 /* Of course, there's the possibility that neither PATH_MAX nor NAME_MAX
  50    exist.  It's also possible that NAME_MAX exists but is define to a
  51    very small value (HP-UX offers 14), so we need to check if we got a
  52    result, and if it meets a minimum standard, and create or change it
  53    if not. */
  54 #if !defined(LP_ENTRY_SIZE) || LP_ENTRY_SIZE<255
  55 # undef LP_ENTRY_SIZE
  56 # define LP_ENTRY_SIZE 255
  57 #endif
  58
  59 struct LP_dir_context_st
  60 {
  61   DIR *dir;
  62   char entry_name[LP_ENTRY_SIZE+1];
  63 };
  64
  65 const char *LP_find_file(LP_DIR_CTX **ctx, const char *directory)
  66 {
  67   struct dirent *direntry = NULL;
  68
  69   if (ctx == NULL || directory == NULL)
  70     {
  71       errno = EINVAL;
  72       return 0;
  73     }
  74
  75   errno = 0;
  76   if (*ctx == NULL)
  77     {
  78       *ctx = (LP_DIR_CTX *)malloc(sizeof(LP_DIR_CTX));
  79       if (*ctx == NULL)
  80         {
  81           errno = ENOMEM;
  82           return 0;
  83         }
  84       memset(*ctx, '\0', sizeof(LP_DIR_CTX));
  85
  86       (*ctx)->dir = opendir(directory);
  87       if ((*ctx)->dir == NULL)
  88         {
  89           int save_errno = errno; /* Probably not needed, but I'm paranoid */
  90           free(*ctx);
  91           *ctx = NULL;
  92           errno = save_errno;
  93           return 0;
  94         }
  95     }
  96
  97   direntry = readdir((*ctx)->dir);
  98   if (direntry == NULL)
  99     {
 100       return 0;
 101     }
 102
 103   strncpy((*ctx)->entry_name, direntry->d_name, sizeof((*ctx)->entry_name) - 1);
 104   (*ctx)->entry_name[sizeof((*ctx)->entry_name) - 1] = '\0';
 105   return (*ctx)->entry_name;
 106 }
 107
 108 int LP_find_file_end(LP_DIR_CTX **ctx)
 109 {
 110   if (ctx != NULL && *ctx != NULL)
 111     {
 112       int ret = closedir((*ctx)->dir);
 113
 114       free(*ctx);
 115       switch (ret)
 116         {
 117         case 0:
 118           return 1;
 119         case -1:
 120           return 0;
 121         default:
 122           break;
 123         }
 124     }
 125   errno = EINVAL;
 126   return 0;
 127 }