X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Frename.c;h=ca3a6696c842d4588cd1065fb540d26a6b8549b3;hb=718991da5f5026e1a8ce2efcca58359d9b67b2f5;hp=22310be330b281b3ad80f1a5f63fbfda6a28e725;hpb=2f45acc353ef4116714ea582434c7a8318e3e486;p=gnulib.git diff --git a/lib/rename.c b/lib/rename.c index 22310be33..ca3a6696c 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, 2009-2010 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; + + /* 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. */ + /* 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: @@ -134,17 +264,15 @@ rpl_rename (char const *src, char const *dst) #else /* ! W32 platform */ -# if RENAME_DEST_EXISTS_BUG -# error Please report your platform and this message to bug-gnulib@gnu.org. -# elif RENAME_TRAILING_SLASH_SOURCE_BUG || RENAME_TRAILING_SLASH_DEST_BUG - -# include -# include -# include -# include -# include +# include +# include +# include +# include +# include +# include -# include "dirname.h" +# include "dirname.h" +# include "same-inode.h" /* Rename the file SRC to DST, fixing any trailing slash bugs. */ @@ -157,6 +285,7 @@ rpl_rename (char const *src, char const *dst) 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; @@ -165,10 +294,41 @@ rpl_rename (char const *src, char const *dst) 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 @@ -178,27 +338,35 @@ rpl_rename (char const *src, char const *dst) return -1; if (lstat (dst, &dst_st)) { - if (errno != ENOENT || !S_ISDIR (src_st.st_mode)) + if (errno != ENOENT || (!S_ISDIR (src_st.st_mode) && dst_slash)) return -1; + dst_exists = false; } - else if (!S_ISDIR (dst_st.st_mode)) + else { - errno = ENOTDIR; - return -1; - } - else if (!S_ISDIR (src_st.st_mode)) - { - errno = EISDIR; - 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; } -# if RENAME_TRAILING_SLASH_SOURCE_BUG +# 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, then we must strip the offending slash and check that - we have not encountered a symlink instead of a directory. + 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 @@ -248,7 +416,49 @@ rpl_rename (char const *src, char const *dst) else if (S_ISLNK (dst_st.st_mode)) goto out; } -# endif /* RENAME_TRAILING_SLASH_SOURCE_BUG */ +# 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; @@ -260,5 +470,4 @@ rpl_rename (char const *src, char const *dst) errno = rename_errno; return ret_val; } -# endif /* RENAME_TRAILING_SLASH_*_BUG */ #endif /* ! W32 platform */