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+/* Work around platform bugs in stat.
+ Copyright (C) 2009-2022 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ This file 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 Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser 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
+}