diff options
Diffstat (limited to 'sysdeps/mach/hurd')
-rw-r--r-- | sysdeps/mach/hurd/readlinkat.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/sysdeps/mach/hurd/readlinkat.c b/sysdeps/mach/hurd/readlinkat.c new file mode 100644 index 0000000000..b70f9c8dea --- /dev/null +++ b/sysdeps/mach/hurd/readlinkat.c @@ -0,0 +1,64 @@ +/* Copyright (C) 1991-2012 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <unistd.h> +#include <hurd.h> +#include <hurd/paths.h> +#include <hurd/fd.h> +#include <fcntl.h> +#include <string.h> + +/* Read the contents of the symbolic link FILE_NAME relative to FD into no more + than LEN bytes of BUF. The contents are not null-terminated. + Returns the number of characters read, or -1 for errors. */ +ssize_t +readlinkat (fd, file_name, buf, len) + int fd; + const char *file_name; + char *buf; + size_t len; +{ + error_t err; + file_t file; + struct stat64 st; + + file = __file_name_lookup_at (fd, 0, file_name, O_READ | O_NOLINK, 0); + if (file == MACH_PORT_NULL) + return -1; + + err = __io_stat (file, &st); + if (! err) + if (S_ISLNK (st.st_mode)) + { + char *rbuf = buf; + + err = __io_read (file, &rbuf, &len, 0, len); + if (!err && rbuf != buf) + { + memcpy (buf, rbuf, len); + __vm_deallocate (__mach_task_self (), (vm_address_t)rbuf, len); + } + } + else + err = EINVAL; + + __mach_port_deallocate (__mach_task_self (), file); + + return err ? __hurd_fail (err) : len; +} +libc_hidden_def (readlinkat) |