gnulib/lib/utime.c - toolchain/make - Git at Google

 /* Work around platform bugs in utime.
    Copyright (C) 2017-2020 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/>.  */

 /* Written by Bruno Haible.  */

 #include <config.h>

 /* Specification.  */
 #include <utime.h>

 #if defined _WIN32 && ! defined __CYGWIN__

 # include <errno.h>
 # include <stdbool.h>
 # include <windows.h>
 # include "filename.h"
 # include "malloca.h"

 int
 _gl_utimens_windows (const char *name, struct timespec ts[2])
 {
   /* 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--;
     }

   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;
     }

   DWORD error;

   /* 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 handle =
     CreateFile (rname,
                 FILE_READ_ATTRIBUTES | FILE_WRITE_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 (handle == INVALID_HANDLE_VALUE)
     {
       error = GetLastError ();
       goto failed;
     }

   if (check_dir)
     {
       /* GetFileAttributes
          <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-getfileattributesa>  */
       DWORD attributes = GetFileAttributes (rname);
       if (attributes == INVALID_FILE_ATTRIBUTES)
         {
           error = GetLastError ();
           CloseHandle (handle);
           goto failed;
         }
       if ((attributes & FILE_ATTRIBUTE_DIRECTORY) == 0)
         {
           CloseHandle (handle);
           if (malloca_rname != NULL)
             freea (malloca_rname);
           errno = ENOTDIR;
           return -1;
         }
     }

   {
     /* Use SetFileTime(). See
        <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-setfiletime>
        <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-filetime>  */
     FILETIME last_access_time;
     FILETIME last_write_time;
     if (ts == NULL)
       {
         /* GetSystemTimeAsFileTime is the same as
            GetSystemTime followed by SystemTimeToFileTime.
            <https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimeasfiletime>.
            It would be overkill to use
            GetSystemTimePreciseAsFileTime
            <https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimepreciseasfiletime>.  */
         FILETIME current_time;
         GetSystemTimeAsFileTime (&current_time);
         last_access_time = current_time;
         last_write_time = current_time;
       }
     else
       {
         {
           ULONGLONG time_since_16010101 =
             (ULONGLONG) ts[0].tv_sec * 10000000 + ts[0].tv_nsec / 100 + 116444736000000000LL;
           last_access_time.dwLowDateTime = (DWORD) time_since_16010101;
           last_access_time.dwHighDateTime = time_since_16010101 >> 32;
         }
         {
           ULONGLONG time_since_16010101 =
             (ULONGLONG) ts[1].tv_sec * 10000000 + ts[1].tv_nsec / 100 + 116444736000000000LL;
           last_write_time.dwLowDateTime = (DWORD) time_since_16010101;
           last_write_time.dwHighDateTime = time_since_16010101 >> 32;
         }
       }
     if (SetFileTime (handle, NULL, &last_access_time, &last_write_time))
       {
         CloseHandle (handle);
         if (malloca_rname != NULL)
           freea (malloca_rname);
         return 0;
       }
     else
       {
         #if 0
         DWORD sft_error = GetLastError ();
         fprintf (stderr, "utimens SetFileTime error 0x%x\n", (unsigned int) sft_error);
         #endif
         CloseHandle (handle);
         if (malloca_rname != NULL)
           freea (malloca_rname);
         errno = EINVAL;
         return -1;
       }
   }

  failed:
   {
     #if 0
     fprintf (stderr, "utimens CreateFile/GetFileAttributes 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_NETPATH:    /* rname is such as '\\nonexistentserver\share'.  */
       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'.  */
         errno = (ts != NULL ? EPERM : 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;
   }
 }

 int
 utime (const char *name, const struct utimbuf *ts)
 {
   if (ts == NULL)
     return _gl_utimens_windows (name, NULL);
   else
     {
       struct timespec ts_with_nanoseconds[2];
       ts_with_nanoseconds[0].tv_sec = ts->actime;
       ts_with_nanoseconds[0].tv_nsec = 0;
       ts_with_nanoseconds[1].tv_sec = ts->modtime;
       ts_with_nanoseconds[1].tv_nsec = 0;
       return _gl_utimens_windows (name, ts_with_nanoseconds);
     }
 }

 #endif
	/* Work around platform bugs in utime.
	Copyright (C) 2017-2020 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/>. */

	/* Written by Bruno Haible. */

	#include <config.h>

	/* Specification. */
	#include <utime.h>

	#if defined _WIN32 && ! defined __CYGWIN__

	# include <errno.h>
	# include <stdbool.h>
	# include <windows.h>
	# include "filename.h"
	# include "malloca.h"

	int
	_gl_utimens_windows (const char *name, struct timespec ts[2])
	{
	/* 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--;
	}

	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;
	}

	DWORD error;

	/* 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 handle =
	CreateFile (rname,
	FILE_READ_ATTRIBUTES \| FILE_WRITE_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 (handle == INVALID_HANDLE_VALUE)
	{
	error = GetLastError ();
	goto failed;
	}

	if (check_dir)
	{
	/* GetFileAttributes
	<https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-getfileattributesa> */
	DWORD attributes = GetFileAttributes (rname);
	if (attributes == INVALID_FILE_ATTRIBUTES)
	{
	error = GetLastError ();
	CloseHandle (handle);
	goto failed;
	}
	if ((attributes & FILE_ATTRIBUTE_DIRECTORY) == 0)
	{
	CloseHandle (handle);
	if (malloca_rname != NULL)
	freea (malloca_rname);
	errno = ENOTDIR;
	return -1;
	}
	}

	{
	/* Use SetFileTime(). See
	<https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-setfiletime>
	<https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-filetime> */
	FILETIME last_access_time;
	FILETIME last_write_time;
	if (ts == NULL)
	{
	/* GetSystemTimeAsFileTime is the same as
	GetSystemTime followed by SystemTimeToFileTime.
	<https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimeasfiletime>.
	It would be overkill to use
	GetSystemTimePreciseAsFileTime
	<https://docs.microsoft.com/en-us/windows/desktop/api/sysinfoapi/nf-sysinfoapi-getsystemtimepreciseasfiletime>. */
	FILETIME current_time;
	GetSystemTimeAsFileTime (&current_time);
	last_access_time = current_time;
	last_write_time = current_time;
	}
	else
	{
	{
	ULONGLONG time_since_16010101 =
	(ULONGLONG) ts[0].tv_sec * 10000000 + ts[0].tv_nsec / 100 + 116444736000000000LL;
	last_access_time.dwLowDateTime = (DWORD) time_since_16010101;
	last_access_time.dwHighDateTime = time_since_16010101 >> 32;
	}
	{
	ULONGLONG time_since_16010101 =
	(ULONGLONG) ts[1].tv_sec * 10000000 + ts[1].tv_nsec / 100 + 116444736000000000LL;
	last_write_time.dwLowDateTime = (DWORD) time_since_16010101;
	last_write_time.dwHighDateTime = time_since_16010101 >> 32;
	}
	}
	if (SetFileTime (handle, NULL, &last_access_time, &last_write_time))
	{
	CloseHandle (handle);
	if (malloca_rname != NULL)
	freea (malloca_rname);
	return 0;
	}
	else
	{
	#if 0
	DWORD sft_error = GetLastError ();
	fprintf (stderr, "utimens SetFileTime error 0x%x\n", (unsigned int) sft_error);
	#endif
	CloseHandle (handle);
	if (malloca_rname != NULL)
	freea (malloca_rname);
	errno = EINVAL;
	return -1;
	}
	}

	failed:
	{
	#if 0
	fprintf (stderr, "utimens CreateFile/GetFileAttributes 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_NETPATH: /* rname is such as '\\nonexistentserver\share'. */
	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'. */
	errno = (ts != NULL ? EPERM : 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;
	}
	}

	int
	utime (const char name, const struct utimbuf ts)
	{
	if (ts == NULL)
	return _gl_utimens_windows (name, NULL);
	else
	{
	struct timespec ts_with_nanoseconds[2];
	ts_with_nanoseconds[0].tv_sec = ts->actime;
	ts_with_nanoseconds[0].tv_nsec = 0;
	ts_with_nanoseconds[1].tv_sec = ts->modtime;
	ts_with_nanoseconds[1].tv_nsec = 0;
	return _gl_utimens_windows (name, ts_with_nanoseconds);
	}
	}

	#endif