compiler/posixc/scandir.c

   1 /*
   2     Copyright © 1995-2017, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     POSIX.1-2008 function scandir().
   6 */
   7
   8 #include <errno.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <dirent.h>
  16
  17         int scandir (
  18
  19 /*  SYNOPSIS */
  20         const char *dir,
  21         struct dirent ***namelist,
  22         int (*select)(const struct dirent *),
  23         int (*compar)(const struct dirent **, const struct dirent **)
  24         )
  25
  26 /*  FUNCTION
  27         Scan directory
  28
  29     INPUTS
  30         dir      - Directory to be scanned
  31         namelist - Array with the found entries.
  32         select   - Filter function which must return non-zero if entry shall be
  33                    added. If NULL all entries will be added.
  34         compar   - Function which will be used by qsort() for sorting of the
  35                    entries. The function alphasort() can be used for sorting
  36                    in alphabetical oder. If NULL sorting order isn't specified.
  37
  38     RESULT
  39         Number of entries
  40
  41     NOTES
  42
  43     EXAMPLE
  44
  45     BUGS
  46
  47     SEE ALSO
  48         alphasort()
  49
  50     INTERNALS
  51
  52 ******************************************************************************/
  53 {
  54     DIR *dirp = NULL;
  55     struct dirent *dp;
  56     struct dirent *newdp;
  57     int cnt = 0;
  58     struct dirent **darr = NULL;
  59     struct dirent **newdarr;
  60     int arrcnt = 0;
  61     int selected;
  62     int olderrno;
  63
  64     errno = 0;
  65
  66     if ((dirp = opendir(dir)) == NULL)
  67     {
  68         goto fail;
  69     }
  70
  71     do
  72     {
  73         if ((dp = readdir(dirp)) != NULL)
  74         {
  75             selected = 0;
  76             if (select != NULL)
  77             {
  78                 olderrno = errno;
  79                 selected = select(dp);
  80                 errno = olderrno;
  81             }
  82             if ((select == NULL) || selected)
  83             {
  84                 if ((darr == NULL) || cnt >= arrcnt)
  85                 {
  86                     arrcnt += 50;
  87                     newdarr = realloc(darr, arrcnt * sizeof(*darr));
  88                     if (newdarr == NULL)
  89                     {
  90                         goto fail;
  91                     }
  92                     darr = newdarr;
  93                 }
  94                 newdp = malloc(sizeof(*newdp));
  95                 if (newdp == NULL)
  96                 {
  97                     goto fail;
  98                 }
  99                 memcpy(newdp, dp, sizeof(*newdp));
 100                 darr[cnt] = newdp;
 101                 cnt++;
 102             }
 103         }
 104     } while (dp != NULL);
 105
 106     closedir(dirp);
 107
 108     if (compar != NULL)
 109     {
 110         olderrno = errno;
 111         qsort (darr, cnt, sizeof (*darr), (int (*) (const void *, const void *)) compar);
 112         errno = olderrno;
 113     }
 114     *namelist = darr;
 115     return cnt;
 116
 117 fail:
 118     while (cnt > 0)
 119     {
 120         free(darr[--cnt]);
 121     }
 122     free(darr);
 123     closedir(dirp);
 124     return -1;
 125 }