X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Frename.c;h=3e463ea86a92ee8d5e27ba429043e94e142c4bd0;hb=3f5bf99e1290a6b46133385cc7c7515f96f4098b;hp=b6a5dabee25ab8f58d63bb768d4dbaf056b93397;hpb=33790590664b279853404bd753849b71a382ea0a;p=gnulib.git diff --git a/lib/rename.c b/lib/rename.c index b6a5dabee..3e463ea86 100644 --- a/lib/rename.c +++ b/lib/rename.c @@ -1,7 +1,6 @@ /* Work around rename bugs in some systems. - Copyright (C) 2001, 2002, 2003, 2005, 2006, 2009 Free Software - Foundation, Inc. + Copyright (C) 2001-2003, 2005-2006, 2009-2013 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 @@ -30,10 +29,16 @@ existing files. */ # include +# include +# include +# include +# include # 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. */ @@ -41,15 +46,140 @@ 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; - /* MoveFileEx works if SRC is a directory without any flags, - but fails with MOVEFILE_REPLACE_EXISTING, so try without - flags first. */ + /* 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. */ + due to the destination already existing. */ error = GetLastError (); if (error == ERROR_FILE_EXISTS || error == ERROR_ALREADY_EXISTS) { @@ -117,7 +247,7 @@ rpl_rename (char const *src, char const *dst) break; # ifndef ERROR_FILE_TOO_LARGE -/* This value is documented but not defined in all versions of windows.h. */ +/* 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: @@ -215,13 +345,13 @@ rpl_rename (char const *src, char const *dst) 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; - } + { + 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; + return 0; # endif /* RENAME_HARD_LINK_BUG */ dst_exists = true; } @@ -294,9 +424,16 @@ rpl_rename (char const *src, char const *dst) 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. */ + 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);