X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Frename.c;h=2116028217178b2160010ba162fcea8d7fc54507;hb=1276a2c5f24c0c932426aca9c899fa524d2443f2;hp=3788e900eb482cc36b701d0e20885c81ead7cac6;hpb=2516905b58eead5c5285af06e09d350343b9f5fb;p=gnulib.git
diff --git a/lib/rename.c b/lib/rename.c
index 3788e900e..211602821 100644
--- a/lib/rename.c
+++ b/lib/rename.c
@@ -1,10 +1,11 @@
-/* rename.c -- BSD compatible directory function for System V
- Copyright (C) 1988, 1990 Free Software Foundation, Inc.
+/* Work around rename bugs in some systems.
- This program is free software; you can redistribute it and/or modify
+ Copyright (C) 2001-2003, 2005-2006, 2009-2014 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 2, or (at your option)
- any later version.
+ 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
@@ -12,94 +13,461 @@
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, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+ along with this program. If not, see . */
+
+/* Written by Volker Borchert, Eric Blake. */
-#ifdef HAVE_CONFIG_H
#include
-#endif
-#include
-#include
-#include
-#ifndef errno
-extern int errno;
-#endif
+#include
-#ifdef STAT_MACROS_BROKEN
-#undef S_ISDIR
-#endif /* STAT_MACROS_BROKEN. */
+#undef rename
-#if !defined(S_ISDIR) && defined(S_IFDIR)
-#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
-#endif
+#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 "safe-stat.h"
+# include
+# include
+# include
+# include
+# include
-/* Rename file FROM to file TO.
- Return 0 if successful, -1 if not. */
+# define WIN32_LEAN_AND_MEAN
+# include
+# 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
-rename (from, to)
- char *from;
- char *to;
+rpl_rename (char const *src, char const *dst)
{
- struct stat from_stats, to_stats;
- int pid, status;
+ 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;
- if (SAFE_STAT (from, &from_stats))
- return -1;
+ /* 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;
+ }
+ }
- /* Be careful not to unlink `from' if it happens to be equal to `to' or
- (on filesystems that silently truncate filenames after 14 characters)
- if `from' and `to' share the significant characters. */
- if (SAFE_STAT (to, &to_stats))
+ /* 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)
+ if (errno != ENOENT || (!S_ISDIR (src_st.st_mode) && dst_slash))
return -1;
+ dst_exists = false;
}
else
{
- if ((from_stats.st_dev == to_stats.st_dev)
- && (from_stats.st_ino == to_stats.st_dev))
- /* `from' and `to' designate the same file on that filesystem. */
- return 0;
+ 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;
+ }
- if (unlink (to) && errno != ENOENT)
+ /* 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;
}
- if (S_ISDIR (from_stats.st_mode))
+ return -1;
+}
+
+#else /* ! W32 platform */
+
+# include
+# include
+# include
+# include
+# include
+# include
+
+# 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;
+ 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))
{
- /* Need a setuid root process to link and unlink directories. */
- pid = fork ();
- switch (pid)
- {
- case -1: /* Error. */
- error (1, errno, "cannot fork");
-
- case 0: /* Child. */
- execl (MVDIR, "mvdir", from, to, (char *) 0);
- error (255, errno, "cannot run `%s'", MVDIR);
-
- default: /* Parent. */
- while (wait (&status) != pid)
- /* Do nothing. */ ;
-
- errno = 0; /* mvdir printed the system error message. */
- if (status)
- return -1;
- }
+ if (errno != ENOENT || (!S_ISDIR (src_st.st_mode) && dst_slash))
+ return -1;
+ dst_exists = false;
}
else
{
- if (link (from, to))
- return -1;
- if (unlink (from) && errno != ENOENT)
- {
- unlink (to);
- return -1;
- }
+ 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;
}
- return 0;
+
+# 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:
+ if (src_temp != src)
+ free (src_temp);
+ if (dst_temp != dst)
+ free (dst_temp);
+ errno = rename_errno;
+ return ret_val;
}
+#endif /* ! W32 platform */