| /* Message-writing for the dynamic linker. Generic version. |
| Copyright (C) 2013-2018 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, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <sys/uio.h> |
| #include <ldsodefs.h> |
| #include <libc-lock.h> |
| |
| /* This is used from only one place: dl-misc.c:_dl_debug_vdprintf. |
| Hence it's in a header with the expectation it will be inlined. |
| |
| This is writev, but with a constraint added and others loosened: |
| |
| 1. Under RTLD_PRIVATE_ERRNO, it must not clobber the private errno |
| when another thread holds the dl_load_lock. |
| 2. It is not obliged to detect and report errors at all. |
| 3. It's not really obliged to deliver a single atomic write |
| (though it may be preferable). */ |
| |
| static inline void |
| _dl_writev (int fd, const struct iovec *iov, size_t niov) |
| { |
| /* Note that if __writev is an implementation that calls malloc, |
| this will cause linking problems building the dynamic linker. */ |
| |
| #if RTLD_PRIVATE_ERRNO |
| /* We have to take this lock just to be sure we don't clobber the private |
| errno when it's being used by another thread that cares about it. |
| Yet we must be sure not to try calling the lock functions before |
| the thread library is fully initialized. */ |
| if (__glibc_unlikely (_dl_starting_up)) |
| __writev (fd, iov, niov); |
| else |
| { |
| __rtld_lock_lock_recursive (GL(dl_load_lock)); |
| __writev (fd, iov, niov); |
| __rtld_lock_unlock_recursive (GL(dl_load_lock)); |
| } |
| #else |
| __writev (fd, iov, niov); |
| #endif |
| } |