diff options
| -rw-r--r-- | ChangeLog | 7 | ||||
| -rw-r--r-- | elf/dl-misc.c | 23 | ||||
| -rw-r--r-- | elf/dl-writev.h | 56 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/dl-writev.h | 38 |
4 files changed, 104 insertions, 20 deletions
diff --git a/ChangeLog b/ChangeLog index e7215def7f..1c43908d62 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2013-05-06 Roland McGrath <roland@hack.frob.com> + + * elf/dl-writev.h: New file. + * elf/dl-misc.c: Include it. + (_dl_debug_vdprintf): Call _dl_writev instead of __writev et al. + * sysdeps/unix/sysv/linux/dl-writev.h: New file. + 2013-05-04 Joseph Myers <joseph@codesourcery.com> * math/libm-test.inc (noXFails): Remove variable. diff --git a/elf/dl-misc.c b/elf/dl-misc.c index a8e9a3f2f0..e0e105b88f 100644 --- a/elf/dl-misc.c +++ b/elf/dl-misc.c @@ -31,7 +31,8 @@ #include <sys/uio.h> #include <sysdep.h> #include <_itoa.h> -#include <bits/libc-lock.h> +#include <dl-writev.h> + /* Read the whole contents of FILE into new mmap'd space with given protections. *SIZEP gets the size of the file. On error MAP_FAILED @@ -239,25 +240,7 @@ _dl_debug_vdprintf (int fd, int tag_p, const char *fmt, va_list arg) } /* Finally write the result. */ -#ifdef HAVE_INLINED_SYSCALLS - INTERNAL_SYSCALL_DECL (err); - INTERNAL_SYSCALL (writev, err, 3, fd, &iov, niov); -#elif 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 (__builtin_expect (INTUSE (_dl_starting_up), 0)) - __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 + _dl_writev (fd, iov, niov); } diff --git a/elf/dl-writev.h b/elf/dl-writev.h new file mode 100644 index 0000000000..0fc0b2b864 --- /dev/null +++ b/elf/dl-writev.h @@ -0,0 +1,56 @@ +/* Message-writing for the dynamic linker. Generic version. + Copyright (C) 2013 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 <bits/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 (__builtin_expect (INTUSE (_dl_starting_up), 0)) + __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 +} diff --git a/sysdeps/unix/sysv/linux/dl-writev.h b/sysdeps/unix/sysv/linux/dl-writev.h new file mode 100644 index 0000000000..b682e0c4b6 --- /dev/null +++ b/sysdeps/unix/sysv/linux/dl-writev.h @@ -0,0 +1,38 @@ +/* Message-writing for the dynamic linker. Linux version. + Copyright (C) 2013 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 <sysdep.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) +{ + INTERNAL_SYSCALL_DECL (err); + INTERNAL_SYSCALL (writev, err, 3, fd, iov, niov); +} |