stat.c

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Hash : 26fd3545
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Date : 2025-09-16T23:08:01

stringeq: prefer streq to strcmp in other modules

* lib/acl-internal.c, lib/argmatch.c, lib/argp-help.c:
* lib/argp-parse.c, lib/bcp47.c, lib/c32_get_mapping.c:
* lib/c32_get_type_test.c, lib/concat-filename.c:
* lib/cpu-supports.h, lib/dfa.c, lib/duplocale.c, lib/exclude.c:
* lib/findprog-in.c, lib/findprog.c, lib/fopen.c, lib/freopen.c:
* lib/fts.c, lib/gen-uni-tables.c, lib/getfilecon.c:
* lib/getlogin.c, lib/getugroups.c, lib/hard-locale.c:
* lib/hashcode-named-file.c, lib/hashkey-string.c:
* lib/iconv_open.c, lib/idcache.c, lib/lc-charset-unicode.c:
* lib/localcharset.c, lib/localename-environ.c:
* lib/localename-unsafe.c, lib/mbs_endswith.c, lib/mountlist.c:
* lib/newlocale.c, lib/nl_langinfo.c, lib/nproc.c, lib/open.c:
* lib/os2-spawn.c, lib/parse-datetime.y, lib/popen.c:
* lib/progreloc.c, lib/propername.c, lib/pt_chown.c, lib/putenv.c:
* lib/qcopy-acl.c, lib/readutmp.c, lib/rpmatch.c:
* lib/setlocale-fixes.c, lib/setlocale.c, lib/sig2str.c:
* lib/spawni.c, lib/stat.c, lib/str_endswith.c, lib/streq.h:
* lib/striconveha.c, lib/struniq.h, lib/supersede.c:
* lib/time_rz.c, lib/unicodeio.c, lib/vasnprintf.c:
* lib/vc-mtime.c, lib/wctrans-impl.h, lib/wctype-impl.h:
Prefer streq to strcmp when either will do.
Do not make this change to files shared with glibc.
Do not make the change to test files, at least not for now.
* lib/gen-uni-tables.c (streq): New static function, in same style.
* modules/acl-permissions, modules/argp, modules/c32_get_mapping:
* modules/c32_get_type_test, modules/concat-filename:
* modules/cpu-supports, modules/dfa, modules/duplocale:
* modules/exclude, modules/findprog, modules/findprog-in:
* modules/fopen, modules/fopen-gnu, modules/freopen, modules/fts:
* modules/getlocalename_l-simple, modules/getlocalename_l-unsafe:
* modules/getlogin, modules/getugroups, modules/hard-locale:
* modules/hashcode-named-file, modules/hashkey-string:
* modules/iconv_open, modules/idcache, modules/localcharset:
* modules/localename, modules/localename-unsafe:
* modules/mbs_endswith, modules/mountlist, modules/newlocale:
* modules/nl_langinfo, modules/nproc, modules/open:
* modules/parse-datetime, modules/popen:
* modules/posix_spawn-internal, modules/propername:
* modules/pt_chown, modules/putenv-gnu, modules/qcopy-acl:
* modules/rpmatch, modules/selinux-h, modules/setenv:
* modules/setlocale, modules/setlocale-fixes, modules/sig2str:
* modules/spawn-pipe, modules/stat, modules/str_endswith:
* modules/streq, modules/striconveha, modules/supersede:
* modules/time_rz, modules/uchar-h, modules/unicodeio:
* modules/uniconv/base, modules/wctrans, modules/wctype:
(Depends-on): Add stringeq.

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lib/stat.c

/* Work around platform bugs in stat.
   Copyright (C) 2009-2025 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.  */
#include <sys/stat.h>

#include "stat-time.h"

#include <errno.h>
#include <limits.h>
#include <string.h>
#include "filename.h"
#include "malloca.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> ?  */

  /* To ease portability.  Like in open.c.  */
  if (streq (name, "/dev/null"))
    name = "NUL";

  /* 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
}

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kc3-lang/gnulib/lib/stat.c

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lib/stat.c