rm_/lib/readdir.c

99 lines
2.9 KiB
C
Raw Permalink Normal View History

2020-09-02 16:47:03 +08:00
/* Read the next entry of a directory.
Copyright (C) 2011-2020 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include <dirent.h>
#include <errno.h>
#include <stddef.h>
#include "dirent-private.h"
struct dirent *
readdir (DIR *dirp)
{
char type;
struct dirent *result;
/* There is no need to add code to produce entries for "." and "..".
According to the POSIX:2008 section "4.12 Pathname Resolution"
<https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html>
"." and ".." are syntactic entities.
POSIX also says:
"If entries for dot or dot-dot exist, one entry shall be returned
for dot and one entry shall be returned for dot-dot; otherwise,
they shall not be returned." */
switch (dirp->status)
{
case -2:
/* End of directory already reached. */
return NULL;
case -1:
break;
case 0:
if (!FindNextFile (dirp->current, &dirp->entry))
{
switch (GetLastError ())
{
case ERROR_NO_MORE_FILES:
dirp->status = -2;
return NULL;
default:
errno = EIO;
return NULL;
}
}
break;
default:
errno = dirp->status;
return NULL;
}
dirp->status = 0;
if (dirp->entry.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
type = DT_DIR;
else if (dirp->entry.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)
type = DT_LNK;
else if ((dirp->entry.dwFileAttributes
& ~(FILE_ATTRIBUTE_READONLY
| FILE_ATTRIBUTE_HIDDEN
| FILE_ATTRIBUTE_SYSTEM
| FILE_ATTRIBUTE_ARCHIVE
| FILE_ATTRIBUTE_NORMAL
| FILE_ATTRIBUTE_TEMPORARY
| FILE_ATTRIBUTE_SPARSE_FILE
| FILE_ATTRIBUTE_COMPRESSED
| FILE_ATTRIBUTE_NOT_CONTENT_INDEXED
| FILE_ATTRIBUTE_ENCRYPTED)) == 0)
/* Devices like COM1, LPT1, NUL would also have the attributes 0x20 but
they cannot occur here. */
type = DT_REG;
else
type = DT_UNKNOWN;
/* Reuse the memory of dirp->entry for the result. */
result =
(struct dirent *)
((char *) dirp->entry.cFileName - offsetof (struct dirent, d_name[0]));
result->d_type = type;
return result;
}