X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Ffchownat.c;h=4f6a44d040c642e8bf3196c02a2d8c35aff6990a;hb=0aa49ea72a8764e3065ebbfc55459232ca8fb021;hp=c217b5243680be3401f0b2b8e69dbb2e627cf298;hpb=52c658e92436e7ef2d7c7b6f7ee69ae4431b6d7d;p=gnulib.git diff --git a/lib/fchownat.c b/lib/fchownat.c index c217b5243..4f6a44d04 100644 --- a/lib/fchownat.c +++ b/lib/fchownat.c @@ -4,7 +4,7 @@ when the buggy fchownat-with-AT_SYMLINK_NOFOLLOW operates on a symlink, it mistakenly affects the symlink referent, rather than the symlink itself. - Copyright (C) 2006-2007, 2009 Free Software Foundation, Inc. + Copyright (C) 2006-2007, 2009-2012 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 @@ -25,23 +25,90 @@ #include -#include "dirname.h" /* solely for definition of IS_ABSOLUTE_FILE_NAME */ +#include +#include + #include "openat.h" -#include "openat-priv.h" -#include "save-cwd.h" + +#if !HAVE_FCHOWNAT /* Replacement for Solaris' function by the same name. Invoke chown or lchown on file, FILE, using OWNER and GROUP, in the directory open on descriptor FD. If FLAG is AT_SYMLINK_NOFOLLOW, then use lchown, otherwise, use chown. If possible, do it without changing the working directory. Otherwise, resort to using save_cwd/fchdir, - then mkdir/restore_cwd. If either the save_cwd or the restore_cwd - fails, then give a diagnostic and exit nonzero. */ - -#define AT_FUNC_NAME fchownat -#define AT_FUNC_F1 lchown -#define AT_FUNC_F2 chown -#define AT_FUNC_USE_F1_COND flag == AT_SYMLINK_NOFOLLOW -#define AT_FUNC_POST_FILE_PARAM_DECLS , uid_t owner, gid_t group, int flag -#define AT_FUNC_POST_FILE_ARGS , owner, group -#include "at-func.c" + then (chown|lchown)/restore_cwd. If either the save_cwd or the + restore_cwd fails, then give a diagnostic and exit nonzero. */ + +# define AT_FUNC_NAME fchownat +# define AT_FUNC_F1 lchown +# define AT_FUNC_F2 chown +# define AT_FUNC_USE_F1_COND AT_SYMLINK_NOFOLLOW +# define AT_FUNC_POST_FILE_PARAM_DECLS , uid_t owner, gid_t group, int flag +# define AT_FUNC_POST_FILE_ARGS , owner, group +# include "at-func.c" +# undef AT_FUNC_NAME +# undef AT_FUNC_F1 +# undef AT_FUNC_F2 +# undef AT_FUNC_USE_F1_COND +# undef AT_FUNC_POST_FILE_PARAM_DECLS +# undef AT_FUNC_POST_FILE_ARGS + +#else /* HAVE_FCHOWNAT */ + +# undef fchownat + +# if FCHOWNAT_NOFOLLOW_BUG + +/* Failure to handle AT_SYMLINK_NOFOLLOW requires the /proc/self/fd or + fchdir workaround to call lchown for lchownat, but there is no need + to penalize chownat. */ +static int +local_lchownat (int fd, char const *file, uid_t owner, gid_t group); + +# define AT_FUNC_NAME local_lchownat +# define AT_FUNC_F1 lchown +# define AT_FUNC_POST_FILE_PARAM_DECLS , uid_t owner, gid_t group +# define AT_FUNC_POST_FILE_ARGS , owner, group +# include "at-func.c" +# undef AT_FUNC_NAME +# undef AT_FUNC_F1 +# undef AT_FUNC_POST_FILE_PARAM_DECLS +# undef AT_FUNC_POST_FILE_ARGS + +# endif + +/* Work around bugs with trailing slash, using the same workarounds as + chown and lchown. */ + +int +rpl_fchownat (int fd, char const *file, uid_t owner, gid_t group, int flag) +{ +# if FCHOWNAT_NOFOLLOW_BUG + if (flag == AT_SYMLINK_NOFOLLOW) + return local_lchownat (fd, file, owner, group); +# endif +# if FCHOWNAT_EMPTY_FILENAME_BUG + if (file[0] == '\0') + { + errno = ENOENT; + return -1; + } +# endif +# if CHOWN_TRAILING_SLASH_BUG + { + size_t len = strlen (file); + struct stat st; + if (len && file[len - 1] == '/') + { + if (statat (fd, file, &st)) + return -1; + if (flag == AT_SYMLINK_NOFOLLOW) + return fchownat (fd, file, owner, group, 0); + } + } +# endif + return fchownat (fd, file, owner, group, flag); +} + +#endif /* HAVE_FCHOWNAT */