diff options
Diffstat (limited to 'lib/readlink.c')
| -rw-r--r-- | lib/readlink.c | 58 |
1 files changed, 41 insertions, 17 deletions
diff --git a/lib/readlink.c b/lib/readlink.c index 3cbdc1c..e6c3925 100644 --- a/lib/readlink.c +++ b/lib/readlink.c @@ -1,10 +1,10 @@ /* Stub for readlink(). - Copyright (C) 2003-2007 Free Software Foundation, Inc. + Copyright (C) 2003-2007, 2009-2016 Free Software Foundation, Inc. - This program is free software; you can redistribute it and/or modify + 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 @@ -12,8 +12,7 @@ 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <config.h> @@ -21,30 +20,55 @@ #include <unistd.h> #include <errno.h> -#include <sys/types.h> +#include <string.h> #include <sys/stat.h> -#include <stddef.h> #if !HAVE_READLINK /* readlink() substitute for systems that don't have a readlink() function, such as DJGPP 2.03 and mingw32. */ -/* The official POSIX return type of readlink() is ssize_t, but since here - we have no declaration in a public header file, we use 'int' as return - type. */ - -int -readlink (const char *path, char *buf, size_t bufsize) +ssize_t +readlink (const char *name, char *buf _GL_UNUSED, + size_t bufsize _GL_UNUSED) { struct stat statbuf; /* In general we should use lstat() here, not stat(). But on platforms - without symbolic links lstat() - if it exists - would be equivalent to + without symbolic links, lstat() - if it exists - would be equivalent to stat(), therefore we can use stat(). This saves us a configure check. */ - if (stat (path, &statbuf) >= 0) + if (stat (name, &statbuf) >= 0) errno = EINVAL; return -1; } -#endif +#else /* HAVE_READLINK */ + +# undef readlink + +/* readlink() wrapper that uses correct types, for systems like cygwin + 1.5.x where readlink returns int, and which rejects trailing slash, + for Solaris 9. */ + +ssize_t +rpl_readlink (const char *name, char *buf, size_t bufsize) +{ +# if READLINK_TRAILING_SLASH_BUG + size_t len = strlen (name); + if (len && name[len - 1] == '/') + { + /* Even if name without the slash is a symlink to a directory, + both lstat() and stat() must resolve the trailing slash to + the directory rather than the symlink. We can therefore + safely use stat() to distinguish between EINVAL and + ENOTDIR/ENOENT, avoiding extra overhead of rpl_lstat(). */ + struct stat st; + if (stat (name, &st) == 0) + errno = EINVAL; + return -1; + } +# endif /* READLINK_TRAILING_SLASH_BUG */ + return readlink (name, buf, bufsize); +} + +#endif /* HAVE_READLINK */ |