X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=lib%2Funlink.c;fp=lib%2Funlink.c;h=0000000000000000000000000000000000000000;hb=dc84183747ce1703eb99685b5dbde1f65a143c06;hp=3e42e28692c373861649eaea61675fc773bf0235;hpb=a2016c1de6e4884f6c8ed5cc498f3bf821c25ca4;p=debian%2Fgzip diff --git a/lib/unlink.c b/lib/unlink.c deleted file mode 100644 index 3e42e28..0000000 --- a/lib/unlink.c +++ /dev/null @@ -1,85 +0,0 @@ -/* Work around unlink bugs. - - Copyright (C) 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 - 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 . */ - -#include - -#include - -#include -#include -#include -#include - -#undef unlink - -/* Remove file NAME. - Return 0 if successful, -1 if not. */ - -int -rpl_unlink (char const *name) -{ - /* Work around Solaris 9 bug where unlink("file/") succeeds. */ - size_t len = strlen (name); - int result = 0; - if (len && ISSLASH (name[len - 1])) - { - /* We can't unlink(2) something if it doesn't exist. If it does - exist, then it resolved to a directory, due to the trailing - slash, and POSIX requires that the unlink attempt to remove - that directory (which would leave the symlink dangling). - Unfortunately, Solaris 9 is one of the platforms where the - root user can unlink directories, and we don't want to - cripple this behavior on real directories, even if it is - seldom needed (at any rate, it's nicer to let coreutils' - unlink(1) give the correct errno for non-root users). But we - don't know whether name was an actual directory, or a symlink - to a directory; and due to the bug of ignoring trailing - slash, Solaris 9 would end up successfully unlinking the - symlink instead of the directory. Technically, we could use - realpath to find the canonical directory name to attempt - deletion on. But that is a lot of work for a corner case; so - we instead just use an lstat on the shortened name, and - reject symlinks with trailing slashes. The root user of - unlink(1) will just have to live with the rule that they - can't delete a directory via a symlink. */ - struct stat st; - result = lstat (name, &st); - if (result == 0) - { - /* Trailing NUL will overwrite the trailing slash. */ - char *short_name = malloc (len); - if (!short_name) - { - errno = EPERM; - return -1; - } - memcpy (short_name, name, len); - while (len && ISSLASH (short_name[len - 1])) - short_name[--len] = '\0'; - if (len && (lstat (short_name, &st) || S_ISLNK (st.st_mode))) - { - free (short_name); - errno = EPERM; - return -1; - } - free (short_name); - } - } - if (!result) - result = unlink (name); - return result; -}