lib/roken/dirent.c

   1 /***********************************************************************
   2  * Copyright (c) 2009, Secure Endpoints Inc.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  *
  12  * - Redistributions in binary form must reproduce the above copyright
  13  *   notice, this list of conditions and the following disclaimer in
  14  *   the documentation and/or other materials provided with the
  15  *   distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  20  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  21  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  22  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  26  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  28  * OF THE POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  **********************************************************************/
  31
  32 #ifdef HAVE_CONFIG_H
  33 #include<config.h>
  34 #endif
  35
  36 #include <stdlib.h>
  37 #include <io.h>
  38 #include <string.h>
  39 #include <errno.h>
  40 #include "dirent.h"
  41
  42 #ifndef _WIN32
  43 #error Only implemented for Win32
  44 #endif
  45
  46 struct _dirent_dirinfo {
  47     int             magic;
  48     long            n_entries;
  49     long            nc_entries;
  50     long            cursor;
  51     struct dirent **entries;
  52 };
  53 #define DIRINFO_MAGIC 0xf8c0639d
  54 #define IS_DP(p) ((p) && ((DIR *)(p))->magic == DIRINFO_MAGIC)
  55
  56 #define INITIAL_ENTRIES 16
  57
  58 ROKEN_LIB_FUNCTION DIR * ROKEN_LIB_CALL
  59 opendir(const char * filespec)
  60 {
  61     DIR *              dp;
  62     struct _finddata_t fd;
  63     intptr_t           fd_handle;
  64
  65     memset(&fd, 0, sizeof(fd));
  66
  67     fd_handle = _findfirst(filespec, &fd);
  68
  69     if (fd_handle == -1)
  70         return NULL;
  71
  72     dp = malloc(sizeof(*dp));
  73     if (dp == NULL)
  74         goto done;
  75
  76     memset(dp, 0, sizeof(*dp));
  77     dp->magic      = DIRINFO_MAGIC;
  78     dp->cursor     = 0;
  79     dp->n_entries  = 0;
  80     dp->nc_entries = INITIAL_ENTRIES;
  81     dp->entries    = calloc(dp->nc_entries, sizeof(dp->entries[0]));
  82
  83     if (dp->entries == NULL) {
  84         closedir(dp);
  85         dp = NULL;
  86         goto done;
  87     }
  88
  89     do {
  90         size_t len = strlen(fd.name);
  91         struct dirent * e;
  92
  93         if (dp->n_entries == dp->nc_entries) {
  94             struct dirent ** ne;
  95
  96             dp->nc_entries *= 2;
  97             ne = realloc(dp->entries, sizeof(dp->entries[0]) * dp->nc_entries);
  98
  99             if (ne == NULL) {
 100                 closedir(dp);
 101                 dp = NULL;
 102                 goto done;
 103             }
 104
 105             dp->entries = ne;
 106         }
 107
 108         e = malloc(sizeof(*e) + len * sizeof(char));
 109         if (e == NULL) {
 110             closedir(dp);
 111             dp = NULL;
 112             goto done;
 113         }
 114
 115         e->d_ino = 0;           /* no inodes :( */
 116         strcpy_s(e->d_name, len + 1, fd.name);
 117
 118         dp->entries[dp->n_entries++] = e;
 119
 120     } while (_findnext(fd_handle, &fd) == 0);
 121
 122  done:
 123     if (fd_handle != -1)
 124         _findclose(fd_handle);
 125
 126     return dp;
 127 }
 128
 129 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
 130 closedir(DIR * dp)
 131 {
 132     if (!IS_DP(dp))
 133         return EINVAL;
 134
 135     if (dp->entries) {
 136         long i;
 137
 138         for (i=0; i < dp->n_entries; i++) {
 139             free(dp->entries[i]);
 140         }
 141
 142         free(dp->entries);
 143     }
 144
 145     free(dp);
 146
 147     return 0;
 148 }
 149
 150 ROKEN_LIB_FUNCTION struct dirent * ROKEN_LIB_CALL
 151 readdir(DIR * dp)
 152 {
 153     if (!IS_DP(dp) ||
 154         dp->cursor < 0 ||
 155         dp->cursor >= dp->n_entries)
 156
 157         return NULL;
 158
 159     return dp->entries[dp->cursor++];
 160 }
 161
 162 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
 163 rewinddir(DIR * dp)
 164 {
 165     if (IS_DP(dp))
 166         dp->cursor = 0;
 167 }
 168
 169 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
 170 seekdir(DIR * dp, long offset)
 171 {
 172     if (IS_DP(dp) && offset >= 0 && offset < dp->n_entries)
 173         dp->cursor = offset;
 174 }
 175
 176 ROKEN_LIB_FUNCTION long ROKEN_LIB_CALL
 177 telldir(DIR * dp)
 178 {
 179     return dp->cursor;
 180 }