/* Work around platform bugs in stat.
Copyright (C) 2009-2021 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/>. */
/* Written by Eric Blake and Bruno Haible. */
/* If the user's config.h happens to include <sys/stat.h>, let it include only
the system's <sys/stat.h> here, so that orig_stat doesn't recurse to
rpl_stat. */
#define __need_system_sys_stat_h
#include <config.h>
/* Get the original definition of stat. It might be defined as a macro. */
#include <sys/types.h>
#include <sys/stat.h>
#undef __need_system_sys_stat_h
#if defined _WIN32 && ! defined __CYGWIN__
# define WINDOWS_NATIVE
#endif
#if !defined WINDOWS_NATIVE
static int
orig_stat (const char *filename, struct stat *buf)
{
return stat (filename, buf);
}
#endif
/* Specification. */
#ifdef __osf__
/* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
eliminates this include because of the preliminary #include <sys/stat.h>
above. */
# include "sys/stat.h"
#else
# include <sys/stat.h>
#endif
#include "stat-time.h"
#include <errno.h>
#include <limits.h>
#include <stdbool.h>
#include <string.h>
#include "filename.h"
#include "malloca.h"
#include "verify.h"
#ifdef WINDOWS_NATIVE
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
# include "stat-w32.h"
/* Don't assume that UNICODE is not defined. */
# undef WIN32_FIND_DATA
# define WIN32_FIND_DATA WIN32_FIND_DATAA
# undef CreateFile
# define CreateFile CreateFileA
# undef FindFirstFile
# define FindFirstFile FindFirstFileA
#endif
#ifdef WINDOWS_NATIVE
/* Return TRUE if the given file name denotes an UNC root. */
static BOOL
is_unc_root (const char *rname)
{
/* Test whether it has the syntax '\\server\share'. */
if (ISSLASH (rname[0]) && ISSLASH (rname[1]))
{
/* It starts with two slashes. Find the next slash. */
const char *p = rname + 2;
const char *q = p;
while (*q != '\0' && !ISSLASH (*q))
q++;
if (q > p && *q != '\0')
{
/* Found the next slash at q. */
q++;
const char *r = q;
while (*r != '\0' && !ISSLASH (*r))
r++;
if (r > q && *r == '\0')
return TRUE;
}
}
return FALSE;
}
#endif
/* Store information about NAME into ST. Work around bugs with
trailing slashes. Mingw has other bugs (such as st_ino always
being 0 on success) which this wrapper does not work around. But
at least this implementation provides the ability to emulate fchdir
correctly. */
int
rpl_stat (char const *name, struct stat *buf)
{
#ifdef WINDOWS_NATIVE
/* Fill the fields ourselves, because the original stat function returns
values for st_atime, st_mtime, st_ctime that depend on the current time
zone. See
<https://lists.gnu.org/r/bug-gnulib/2017-04/msg00134.html> */
/* XXX Should we convert to wchar_t* and prepend '\\?\', in order to work
around length limitations
<https://docs.microsoft.com/en-us/windows/desktop/FileIO/naming-a-file> ? */
/* POSIX <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13>
specifies: "More than two leading <slash> characters shall be treated as
a single <slash> character." */
if (ISSLASH (name[0]) && ISSLASH (name[1]) && ISSLASH (name[2]))
{
name += 2;
while (ISSLASH (name[1]))
name++;
}
size_t len = strlen (name);
size_t drive_prefix_len = (HAS_DEVICE (name) ? 2 : 0);
/* Remove trailing slashes (except the very first one, at position
drive_prefix_len), but remember their presence. */
size_t rlen;
bool check_dir = false;
rlen = len;
while (rlen > drive_prefix_len && ISSLASH (name[rlen-1]))
{
check_dir = true;
if (rlen == drive_prefix_len + 1)
break;
rlen--;
}
/* Handle '' and 'C:'. */
if (!check_dir && rlen == drive_prefix_len)
{
errno = ENOENT;
return -1;
}
/* Handle '\\'. */
if (rlen == 1 && ISSLASH (name[0]) && len >= 2)
{
errno = ENOENT;
return -1;
}
const char *rname;
char *malloca_rname;
if (rlen == len)
{
rname = name;
malloca_rname = NULL;
}
else
{
malloca_rname = malloca (rlen + 1);
if (malloca_rname == NULL)
{
errno = ENOMEM;
return -1;
}
memcpy (malloca_rname, name, rlen);
malloca_rname[rlen] = '\0';
rname = malloca_rname;
}
/* There are two ways to get at the requested information:
- by scanning the parent directory and examining the relevant
directory entry,
- by opening the file directly.
The first approach fails for root directories (e.g. 'C:\') and
UNC root directories (e.g. '\\server\share').
The second approach fails for some system files (e.g. 'C:\pagefile.sys'
and 'C:\hiberfil.sys'): ERROR_SHARING_VIOLATION.
The second approach gives more information (in particular, correct
st_dev, st_ino, st_nlink fields).
So we use the second approach and, as a fallback except for root and
UNC root directories, also the first approach. */
{
int ret;
{
/* Approach based on the file. */
/* Open a handle to the file.
CreateFile
<https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-createfilea>
<https://docs.microsoft.com/en-us/windows/desktop/FileIO/creating-and-opening-files> */
HANDLE h =
CreateFile (rname,
FILE_READ_ATTRIBUTES,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
NULL,
OPEN_EXISTING,
/* FILE_FLAG_POSIX_SEMANTICS (treat file names that differ only
in case as different) makes sense only when applied to *all*
filesystem operations. */
FILE_FLAG_BACKUP_SEMANTICS /* | FILE_FLAG_POSIX_SEMANTICS */,
NULL);
if (h != INVALID_HANDLE_VALUE)
{
ret = _gl_fstat_by_handle (h, rname, buf);
CloseHandle (h);
goto done;
}
}
/* Test for root and UNC root directories. */
if ((rlen == drive_prefix_len + 1 && ISSLASH (rname[drive_prefix_len]))
|| is_unc_root (rname))
goto failed;
/* Fallback. */
{
/* Approach based on the directory entry. */
if (strchr (rname, '?') != NULL || strchr (rname, '*') != NULL)
{
/* Other Windows API functions would fail with error
ERROR_INVALID_NAME. */
if (malloca_rname != NULL)
freea (malloca_rname);
errno = ENOENT;
return -1;
}
/* Get the details about the directory entry. This can be done through
FindFirstFile
<https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-findfirstfilea>
<https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-_win32_find_dataa>
or through
FindFirstFileEx with argument FindExInfoBasic
<https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-findfirstfileexa>
<https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ne-minwinbase-findex_info_levels>
<https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-_win32_find_dataa> */
WIN32_FIND_DATA info;
HANDLE h = FindFirstFile (rname, &info);
if (h == INVALID_HANDLE_VALUE)
goto failed;
/* Test for error conditions before starting to fill *buf. */
if (sizeof (buf->st_size) <= 4 && info.nFileSizeHigh > 0)
{
FindClose (h);
if (malloca_rname != NULL)
freea (malloca_rname);
errno = EOVERFLOW;
return -1;
}
# if _GL_WINDOWS_STAT_INODES
buf->st_dev = 0;
# if _GL_WINDOWS_STAT_INODES == 2
buf->st_ino._gl_ino[0] = buf->st_ino._gl_ino[1] = 0;
# else /* _GL_WINDOWS_STAT_INODES == 1 */
buf->st_ino = 0;
# endif
# else
/* st_ino is not wide enough for identifying a file on a device.
Without st_ino, st_dev is pointless. */
buf->st_dev = 0;
buf->st_ino = 0;
# endif
/* st_mode. */
unsigned int mode =
/* XXX How to handle FILE_ATTRIBUTE_REPARSE_POINT ? */
((info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) ? _S_IFDIR | S_IEXEC_UGO : _S_IFREG)
| S_IREAD_UGO
| ((info.dwFileAttributes & FILE_ATTRIBUTE_READONLY) ? 0 : S_IWRITE_UGO);
if (!(info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
{
/* Determine whether the file is executable by looking at the file
name suffix. */
if (info.nFileSizeHigh > 0 || info.nFileSizeLow > 0)
{
const char *last_dot = NULL;
const char *p;
for (p = info.cFileName; *p != '\0'; p++)
if (*p == '.')
last_dot = p;
if (last_dot != NULL)
{
const char *suffix = last_dot + 1;
if (_stricmp (suffix, "exe") == 0
|| _stricmp (suffix, "bat") == 0
|| _stricmp (suffix, "cmd") == 0
|| _stricmp (suffix, "com") == 0)
mode |= S_IEXEC_UGO;
}
}
}
buf->st_mode = mode;
/* st_nlink. Ignore hard links here. */
buf->st_nlink = 1;
/* There's no easy way to map the Windows SID concept to an integer. */
buf->st_uid = 0;
buf->st_gid = 0;
/* st_rdev is irrelevant for normal files and directories. */
buf->st_rdev = 0;
/* st_size. */
if (sizeof (buf->st_size) <= 4)
/* Range check already done above. */
buf->st_size = info.nFileSizeLow;
else
buf->st_size = ((long long) info.nFileSizeHigh << 32) | (long long) info.nFileSizeLow;
/* st_atime, st_mtime, st_ctime. */
# if _GL_WINDOWS_STAT_TIMESPEC
buf->st_atim = _gl_convert_FILETIME_to_timespec (&info.ftLastAccessTime);
buf->st_mtim = _gl_convert_FILETIME_to_timespec (&info.ftLastWriteTime);
buf->st_ctim = _gl_convert_FILETIME_to_timespec (&info.ftCreationTime);
# else
buf->st_atime = _gl_convert_FILETIME_to_POSIX (&info.ftLastAccessTime);
buf->st_mtime = _gl_convert_FILETIME_to_POSIX (&info.ftLastWriteTime);
buf->st_ctime = _gl_convert_FILETIME_to_POSIX (&info.ftCreationTime);
# endif
FindClose (h);
ret = 0;
}
done:
if (ret >= 0 && check_dir && !S_ISDIR (buf->st_mode))
{
errno = ENOTDIR;
ret = -1;
}
if (malloca_rname != NULL)
{
int saved_errno = errno;
freea (malloca_rname);
errno = saved_errno;
}
return ret;
}
failed:
{
DWORD error = GetLastError ();
#if 0
fprintf (stderr, "rpl_stat error 0x%x\n", (unsigned int) error);
#endif
if (malloca_rname != NULL)
freea (malloca_rname);
switch (error)
{
/* Some of these errors probably cannot happen with the specific flags
that we pass to CreateFile. But who knows... */
case ERROR_FILE_NOT_FOUND: /* The last component of rname does not exist. */
case ERROR_PATH_NOT_FOUND: /* Some directory component in rname does not exist. */
case ERROR_BAD_PATHNAME: /* rname is such as '\\server'. */
case ERROR_BAD_NET_NAME: /* rname is such as '\\server\nonexistentshare'. */
case ERROR_INVALID_NAME: /* rname contains wildcards, misplaced colon, etc. */
case ERROR_DIRECTORY:
errno = ENOENT;
break;
case ERROR_ACCESS_DENIED: /* rname is such as 'C:\System Volume Information\foo'. */
case ERROR_SHARING_VIOLATION: /* rname is such as 'C:\pagefile.sys' (second approach only). */
/* XXX map to EACCES or EPERM? */
errno = EACCES;
break;
case ERROR_OUTOFMEMORY:
errno = ENOMEM;
break;
case ERROR_WRITE_PROTECT:
errno = EROFS;
break;
case ERROR_WRITE_FAULT:
case ERROR_READ_FAULT:
case ERROR_GEN_FAILURE:
errno = EIO;
break;
case ERROR_BUFFER_OVERFLOW:
case ERROR_FILENAME_EXCED_RANGE:
errno = ENAMETOOLONG;
break;
case ERROR_DELETE_PENDING: /* XXX map to EACCES or EPERM? */
errno = EPERM;
break;
default:
errno = EINVAL;
break;
}
return -1;
}
#else
int result = orig_stat (name, buf);
if (result == 0)
{
# if REPLACE_FUNC_STAT_FILE
/* Solaris 9 mistakenly succeeds when given a non-directory with a
trailing slash. */
if (!S_ISDIR (buf->st_mode))
{
size_t len = strlen (name);
if (ISSLASH (name[len - 1]))
{
errno = ENOTDIR;
return -1;
}
}
# endif /* REPLACE_FUNC_STAT_FILE */
result = stat_time_normalize (result, buf);
}
return result;
#endif
}