476 lines
13 KiB
C
476 lines
13 KiB
C
/* Work around rename bugs in some systems.
|
|
|
|
Copyright (C) 2001-2003, 2005-2006, 2009-2016 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 <http://www.gnu.org/licenses/>. */
|
|
|
|
/* Written by Volker Borchert, Eric Blake. */
|
|
|
|
#include <config.h>
|
|
|
|
#include <stdio.h>
|
|
|
|
#undef rename
|
|
|
|
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
|
|
/* The mingw rename has problems with trailing slashes; it also
|
|
requires use of native Windows calls to allow atomic renames over
|
|
existing files. */
|
|
|
|
# include <errno.h>
|
|
# include <stdbool.h>
|
|
# include <stdlib.h>
|
|
# include <sys/stat.h>
|
|
# include <unistd.h>
|
|
|
|
# define WIN32_LEAN_AND_MEAN
|
|
# include <windows.h>
|
|
|
|
# include "dirname.h"
|
|
|
|
/* Rename the file SRC to DST. This replacement is necessary on
|
|
Windows, on which the system rename function will not replace
|
|
an existing DST. */
|
|
int
|
|
rpl_rename (char const *src, char const *dst)
|
|
{
|
|
int error;
|
|
size_t src_len = strlen (src);
|
|
size_t dst_len = strlen (dst);
|
|
char *src_base = last_component (src);
|
|
char *dst_base = last_component (dst);
|
|
bool src_slash;
|
|
bool dst_slash;
|
|
bool dst_exists;
|
|
struct stat src_st;
|
|
struct stat dst_st;
|
|
|
|
/* Filter out dot as last component. */
|
|
if (!src_len || !dst_len)
|
|
{
|
|
errno = ENOENT;
|
|
return -1;
|
|
}
|
|
if (*src_base == '.')
|
|
{
|
|
size_t len = base_len (src_base);
|
|
if (len == 1 || (len == 2 && src_base[1] == '.'))
|
|
{
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
}
|
|
if (*dst_base == '.')
|
|
{
|
|
size_t len = base_len (dst_base);
|
|
if (len == 1 || (len == 2 && dst_base[1] == '.'))
|
|
{
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* Presence of a trailing slash requires directory semantics. If
|
|
the source does not exist, or if the destination cannot be turned
|
|
into a directory, give up now. Otherwise, strip trailing slashes
|
|
before calling rename. There are no symlinks on mingw, so stat
|
|
works instead of lstat. */
|
|
src_slash = ISSLASH (src[src_len - 1]);
|
|
dst_slash = ISSLASH (dst[dst_len - 1]);
|
|
if (stat (src, &src_st))
|
|
return -1;
|
|
if (stat (dst, &dst_st))
|
|
{
|
|
if (errno != ENOENT || (!S_ISDIR (src_st.st_mode) && dst_slash))
|
|
return -1;
|
|
dst_exists = false;
|
|
}
|
|
else
|
|
{
|
|
if (S_ISDIR (dst_st.st_mode) != S_ISDIR (src_st.st_mode))
|
|
{
|
|
errno = S_ISDIR (dst_st.st_mode) ? EISDIR : ENOTDIR;
|
|
return -1;
|
|
}
|
|
dst_exists = true;
|
|
}
|
|
|
|
/* There are no symlinks, so if a file existed with a trailing
|
|
slash, it must be a directory, and we don't have to worry about
|
|
stripping strip trailing slash. However, mingw refuses to
|
|
replace an existing empty directory, so we have to help it out.
|
|
And canonicalize_file_name is not yet ported to mingw; however,
|
|
for directories, getcwd works as a viable alternative. Ensure
|
|
that we can get back to where we started before using it; later
|
|
attempts to return are fatal. Note that we can end up losing a
|
|
directory if rename then fails, but it was empty, so not much
|
|
damage was done. */
|
|
if (dst_exists && S_ISDIR (dst_st.st_mode))
|
|
{
|
|
char *cwd = getcwd (NULL, 0);
|
|
char *src_temp;
|
|
char *dst_temp;
|
|
if (!cwd || chdir (cwd))
|
|
return -1;
|
|
if (IS_ABSOLUTE_FILE_NAME (src))
|
|
{
|
|
dst_temp = chdir (dst) ? NULL : getcwd (NULL, 0);
|
|
src_temp = chdir (src) ? NULL : getcwd (NULL, 0);
|
|
}
|
|
else
|
|
{
|
|
src_temp = chdir (src) ? NULL : getcwd (NULL, 0);
|
|
if (!IS_ABSOLUTE_FILE_NAME (dst) && chdir (cwd))
|
|
abort ();
|
|
dst_temp = chdir (dst) ? NULL : getcwd (NULL, 0);
|
|
}
|
|
if (chdir (cwd))
|
|
abort ();
|
|
free (cwd);
|
|
if (!src_temp || !dst_temp)
|
|
{
|
|
free (src_temp);
|
|
free (dst_temp);
|
|
errno = ENOMEM;
|
|
return -1;
|
|
}
|
|
src_len = strlen (src_temp);
|
|
if (strncmp (src_temp, dst_temp, src_len) == 0
|
|
&& (ISSLASH (dst_temp[src_len]) || dst_temp[src_len] == '\0'))
|
|
{
|
|
error = dst_temp[src_len];
|
|
free (src_temp);
|
|
free (dst_temp);
|
|
if (error)
|
|
{
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
if (rmdir (dst))
|
|
{
|
|
error = errno;
|
|
free (src_temp);
|
|
free (dst_temp);
|
|
errno = error;
|
|
return -1;
|
|
}
|
|
free (src_temp);
|
|
free (dst_temp);
|
|
}
|
|
|
|
/* MoveFileEx works if SRC is a directory without any flags, but
|
|
fails with MOVEFILE_REPLACE_EXISTING, so try without flags first.
|
|
Thankfully, MoveFileEx handles hard links correctly, even though
|
|
rename() does not. */
|
|
if (MoveFileEx (src, dst, 0))
|
|
return 0;
|
|
|
|
/* Retry with MOVEFILE_REPLACE_EXISTING if the move failed
|
|
due to the destination already existing. */
|
|
error = GetLastError ();
|
|
if (error == ERROR_FILE_EXISTS || error == ERROR_ALREADY_EXISTS)
|
|
{
|
|
if (MoveFileEx (src, dst, MOVEFILE_REPLACE_EXISTING))
|
|
return 0;
|
|
|
|
error = GetLastError ();
|
|
}
|
|
|
|
switch (error)
|
|
{
|
|
case ERROR_FILE_NOT_FOUND:
|
|
case ERROR_PATH_NOT_FOUND:
|
|
case ERROR_BAD_PATHNAME:
|
|
case ERROR_DIRECTORY:
|
|
errno = ENOENT;
|
|
break;
|
|
|
|
case ERROR_ACCESS_DENIED:
|
|
case ERROR_SHARING_VIOLATION:
|
|
errno = EACCES;
|
|
break;
|
|
|
|
case ERROR_OUTOFMEMORY:
|
|
errno = ENOMEM;
|
|
break;
|
|
|
|
case ERROR_CURRENT_DIRECTORY:
|
|
errno = EBUSY;
|
|
break;
|
|
|
|
case ERROR_NOT_SAME_DEVICE:
|
|
errno = EXDEV;
|
|
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_HANDLE_DISK_FULL:
|
|
case ERROR_DISK_FULL:
|
|
case ERROR_DISK_TOO_FRAGMENTED:
|
|
errno = ENOSPC;
|
|
break;
|
|
|
|
case ERROR_FILE_EXISTS:
|
|
case ERROR_ALREADY_EXISTS:
|
|
errno = EEXIST;
|
|
break;
|
|
|
|
case ERROR_BUFFER_OVERFLOW:
|
|
case ERROR_FILENAME_EXCED_RANGE:
|
|
errno = ENAMETOOLONG;
|
|
break;
|
|
|
|
case ERROR_INVALID_NAME:
|
|
case ERROR_DELETE_PENDING:
|
|
errno = EPERM; /* ? */
|
|
break;
|
|
|
|
# ifndef ERROR_FILE_TOO_LARGE
|
|
/* This value is documented but not defined in all versions of windows.h. */
|
|
# define ERROR_FILE_TOO_LARGE 223
|
|
# endif
|
|
case ERROR_FILE_TOO_LARGE:
|
|
errno = EFBIG;
|
|
break;
|
|
|
|
default:
|
|
errno = EINVAL;
|
|
break;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
#else /* ! W32 platform */
|
|
|
|
# include <errno.h>
|
|
# include <stdio.h>
|
|
# include <stdlib.h>
|
|
# include <string.h>
|
|
# include <sys/stat.h>
|
|
# include <unistd.h>
|
|
|
|
# include "dirname.h"
|
|
# include "same-inode.h"
|
|
|
|
/* Rename the file SRC to DST, fixing any trailing slash bugs. */
|
|
|
|
int
|
|
rpl_rename (char const *src, char const *dst)
|
|
{
|
|
size_t src_len = strlen (src);
|
|
size_t dst_len = strlen (dst);
|
|
char *src_temp = (char *) src;
|
|
char *dst_temp = (char *) dst;
|
|
bool src_slash;
|
|
bool dst_slash;
|
|
bool dst_exists _GL_UNUSED;
|
|
int ret_val = -1;
|
|
int rename_errno = ENOTDIR;
|
|
struct stat src_st;
|
|
struct stat dst_st;
|
|
|
|
if (!src_len || !dst_len)
|
|
return rename (src, dst); /* Let strace see the ENOENT failure. */
|
|
|
|
# if RENAME_DEST_EXISTS_BUG
|
|
{
|
|
char *src_base = last_component (src);
|
|
char *dst_base = last_component (dst);
|
|
if (*src_base == '.')
|
|
{
|
|
size_t len = base_len (src_base);
|
|
if (len == 1 || (len == 2 && src_base[1] == '.'))
|
|
{
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
}
|
|
if (*dst_base == '.')
|
|
{
|
|
size_t len = base_len (dst_base);
|
|
if (len == 1 || (len == 2 && dst_base[1] == '.'))
|
|
{
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
# endif /* RENAME_DEST_EXISTS_BUG */
|
|
|
|
src_slash = src[src_len - 1] == '/';
|
|
dst_slash = dst[dst_len - 1] == '/';
|
|
|
|
# if !RENAME_HARD_LINK_BUG && !RENAME_DEST_EXISTS_BUG
|
|
/* If there are no trailing slashes, then trust the native
|
|
implementation unless we also suspect issues with hard link
|
|
detection or file/directory conflicts. */
|
|
if (!src_slash && !dst_slash)
|
|
return rename (src, dst);
|
|
# endif /* !RENAME_HARD_LINK_BUG && !RENAME_DEST_EXISTS_BUG */
|
|
|
|
/* Presence of a trailing slash requires directory semantics. If
|
|
the source does not exist, or if the destination cannot be turned
|
|
into a directory, give up now. Otherwise, strip trailing slashes
|
|
before calling rename. */
|
|
if (lstat (src, &src_st))
|
|
return -1;
|
|
if (lstat (dst, &dst_st))
|
|
{
|
|
if (errno != ENOENT || (!S_ISDIR (src_st.st_mode) && dst_slash))
|
|
return -1;
|
|
dst_exists = false;
|
|
}
|
|
else
|
|
{
|
|
if (S_ISDIR (dst_st.st_mode) != S_ISDIR (src_st.st_mode))
|
|
{
|
|
errno = S_ISDIR (dst_st.st_mode) ? EISDIR : ENOTDIR;
|
|
return -1;
|
|
}
|
|
# if RENAME_HARD_LINK_BUG
|
|
if (SAME_INODE (src_st, dst_st))
|
|
return 0;
|
|
# endif /* RENAME_HARD_LINK_BUG */
|
|
dst_exists = true;
|
|
}
|
|
|
|
# if (RENAME_TRAILING_SLASH_SOURCE_BUG || RENAME_DEST_EXISTS_BUG \
|
|
|| RENAME_HARD_LINK_BUG)
|
|
/* If the only bug was that a trailing slash was allowed on a
|
|
non-existing file destination, as in Solaris 10, then we've
|
|
already covered that situation. But if there is any problem with
|
|
a trailing slash on an existing source or destination, as in
|
|
Solaris 9, or if a directory can overwrite a symlink, as on
|
|
Cygwin 1.5, or if directories cannot be created with trailing
|
|
slash, as on NetBSD 1.6, then we must strip the offending slash
|
|
and check that we have not encountered a symlink instead of a
|
|
directory.
|
|
|
|
Stripping a trailing slash interferes with POSIX semantics, where
|
|
rename behavior on a symlink with a trailing slash operates on
|
|
the corresponding target directory. We prefer the GNU semantics
|
|
of rejecting any use of a symlink with trailing slash, but do not
|
|
enforce them, since Solaris 10 is able to obey POSIX semantics
|
|
and there might be clients expecting it, as counter-intuitive as
|
|
those semantics are.
|
|
|
|
Technically, we could also follow the POSIX behavior by chasing a
|
|
readlink trail, but that is harder to implement. */
|
|
if (src_slash)
|
|
{
|
|
src_temp = strdup (src);
|
|
if (!src_temp)
|
|
{
|
|
/* Rather than rely on strdup-posix, we set errno ourselves. */
|
|
rename_errno = ENOMEM;
|
|
goto out;
|
|
}
|
|
strip_trailing_slashes (src_temp);
|
|
if (lstat (src_temp, &src_st))
|
|
{
|
|
rename_errno = errno;
|
|
goto out;
|
|
}
|
|
if (S_ISLNK (src_st.st_mode))
|
|
goto out;
|
|
}
|
|
if (dst_slash)
|
|
{
|
|
dst_temp = strdup (dst);
|
|
if (!dst_temp)
|
|
{
|
|
rename_errno = ENOMEM;
|
|
goto out;
|
|
}
|
|
strip_trailing_slashes (dst_temp);
|
|
if (lstat (dst_temp, &dst_st))
|
|
{
|
|
if (errno != ENOENT)
|
|
{
|
|
rename_errno = errno;
|
|
goto out;
|
|
}
|
|
}
|
|
else if (S_ISLNK (dst_st.st_mode))
|
|
goto out;
|
|
}
|
|
# endif /* RENAME_TRAILING_SLASH_SOURCE_BUG || RENAME_DEST_EXISTS_BUG
|
|
|| RENAME_HARD_LINK_BUG */
|
|
|
|
# if RENAME_DEST_EXISTS_BUG
|
|
/* Cygwin 1.5 sometimes behaves oddly when moving a non-empty
|
|
directory on top of an empty one (the old directory name can
|
|
reappear if the new directory tree is removed). Work around this
|
|
by removing the target first, but don't remove the target if it
|
|
is a subdirectory of the source. Note that we can end up losing
|
|
a directory if rename then fails, but it was empty, so not much
|
|
damage was done. */
|
|
if (dst_exists && S_ISDIR (dst_st.st_mode))
|
|
{
|
|
if (src_st.st_dev != dst_st.st_dev)
|
|
{
|
|
rename_errno = EXDEV;
|
|
goto out;
|
|
}
|
|
if (src_temp != src)
|
|
free (src_temp);
|
|
src_temp = canonicalize_file_name (src);
|
|
if (dst_temp != dst)
|
|
free (dst_temp);
|
|
dst_temp = canonicalize_file_name (dst);
|
|
if (!src_temp || !dst_temp)
|
|
{
|
|
rename_errno = ENOMEM;
|
|
goto out;
|
|
}
|
|
src_len = strlen (src_temp);
|
|
if (strncmp (src_temp, dst_temp, src_len) == 0
|
|
&& dst_temp[src_len] == '/')
|
|
{
|
|
rename_errno = EINVAL;
|
|
goto out;
|
|
}
|
|
if (rmdir (dst))
|
|
{
|
|
rename_errno = errno;
|
|
goto out;
|
|
}
|
|
}
|
|
# endif /* RENAME_DEST_EXISTS_BUG */
|
|
|
|
ret_val = rename (src_temp, dst_temp);
|
|
rename_errno = errno;
|
|
|
|
out: _GL_UNUSED_LABEL;
|
|
|
|
if (src_temp != src)
|
|
free (src_temp);
|
|
if (dst_temp != dst)
|
|
free (dst_temp);
|
|
errno = rename_errno;
|
|
return ret_val;
|
|
}
|
|
#endif /* ! W32 platform */
|