Neither the <dlfcn.h> entry points, nor lazy symbol resolution, nor
initial shared library load-up, are cancellation points, so ld.so
should exclusively use I/O primitives that are not cancellable. We
currently achieve this by having the cancellation hooks compile as
no-ops when IS_IN(rtld); this patch changes to using exclusively
_nocancel primitives in the source code instead, which makes the
intent clearer and significantly reduces the amount of code compiled
under IS_IN(rtld) as well as IS_IN(libc) -- in particular,
elf/Makefile no longer thinks we require a copy of unwind.c in
rtld-libc.a. (The older mechanism is preserved as a backstop.)
The bulk of the change is splitting up the files that define the
_nocancel I/O functions, so they don't also define the variants that
*are* cancellation points; after which, the existing logic for picking
out the bits of libc that need to be recompiled as part of ld.so Just
Works. I did this for all of the _nocancel functions, not just the
ones used by ld.so, for consistency.
fcntl was a little tricky because it's only a cancellation point for
certain opcodes (F_SETLKW(64), which can block), and the existing
__fcntl_nocancel wasn't applying the FCNTL_ADJUST_CMD hook, which
strikes me as asking for trouble, especially as the only nontrivial
definition of FCNTL_ADJUST_CMD (for powerpc64) changes F_*LK* opcodes.
To fix this, fcntl_common moves to fcntl_nocancel.c along with
__fcntl_nocancel, and changes its name to the extern (but hidden)
symbol __fcntl_nocancel_adjusted, so that regular fcntl can continue
calling it. __fcntl_nocancel now applies FCNTL_ADJUST_CMD; so that
both both fcntl.c and fcntl_nocancel.c can see it, the only nontrivial
definition moves from sysdeps/u/s/l/powerpc/powerpc64/fcntl.c to
.../powerpc64/sysdep.h and becomes entirely a macro, instead of a macro
that calls an inline function.
The nptl version of libpthread also changes a little, because its
"compat-routines" formerly included files that defined all the
_nocancel functions it uses; instead of continuing to duplicate them,
I exported the relevant ones from libc.so as GLIBC_PRIVATE. Since the
Linux fcntl.c calls a function defined by fcntl_nocancel.c, it can no
longer be used from libpthread.so; instead, introduce a custom
forwarder, pt-fcntl.c, and export __libc_fcntl from libc.so as
GLIBC_PRIVATE. The nios2-linux ABI doesn't include a copy of vfork()
in libpthread, and it was handling that by manipulating
libpthread-routines in .../linux/nios2/Makefile; it is cleaner to do
what other such ports do, and have a pt-vfork.S that defines no symbols.
Right now, it appears that Hurd does not implement _nocancel I/O, so
sysdeps/generic/not-cancel.h will forward everything back to the
regular functions. This changed the names of some of the functions
that sysdeps/mach/hurd/dl-sysdep.c needs to interpose.
* elf/dl-load.c, elf/dl-misc.c, elf/dl-profile.c, elf/rtld.c
* sysdeps/unix/sysv/linux/dl-sysdep.c
Include not-cancel.h. Use __close_nocancel instead of __close,
__open64_nocancel instead of __open, __read_nocancel instead of
__libc_read, and __write_nocancel instead of __libc_write.
* csu/check_fds.c (check_one_fd)
* sysdeps/posix/fdopendir.c (__fdopendir)
* sysdeps/posix/opendir.c (__alloc_dir): Use __fcntl_nocancel
instead of __fcntl and/or __libc_fcntl.
* sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np)
* sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np)
* sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system):
Use __open64_nocancel instead of __open_nocancel.
* sysdeps/unix/sysv/linux/not-cancel.h: Move all of the
hidden_proto declarations to the end and issue them if either
IS_IN(libc) or IS_IN(rtld).
* sysdeps/unix/sysv/linux/Makefile [subdir=io] (sysdep_routines):
Add close_nocancel, fcntl_nocancel, nanosleep_nocancel,
open_nocancel, open64_nocancel, openat_nocancel, pause_nocancel,
read_nocancel, waitpid_nocancel, write_nocancel.
* io/Versions [GLIBC_PRIVATE]: Add __libc_fcntl,
__fcntl_nocancel, __open64_nocancel, __write_nocancel.
* posix/Versions: Add __nanosleep_nocancel, __pause_nocancel.
* nptl/pt-fcntl.c: New file.
* nptl/Makefile (pthread-compat-wrappers): Remove fcntl.
(libpthread-routines): Add pt-fcntl.
* include/fcntl.h (__fcntl_nocancel_adjusted): New function.
(__libc_fcntl): Remove attribute_hidden.
* sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Call
__fcntl_nocancel_adjusted, not fcntl_common.
(__fcntl_nocancel): Move to new file fcntl_nocancel.c.
(fcntl_common): Rename to __fcntl_nocancel_adjusted; also move
to fcntl_nocancel.c.
* sysdeps/unix/sysv/linux/fcntl_nocancel.c: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Remove file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h:
Define FCNTL_ADJUST_CMD here, as a self-contained macro.
* sysdeps/unix/sysv/linux/close.c: Move __close_nocancel to...
* sysdeps/unix/sysv/linux/close_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/nanosleep.c: Move __nanosleep_nocancel to...
* sysdeps/unix/sysv/linux/nanosleep_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/open.c: Move __open_nocancel to...
* sysdeps/unix/sysv/linux/open_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/open64.c: Move __open64_nocancel to...
* sysdeps/unix/sysv/linux/open64_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/openat.c: Move __openat_nocancel to...
* sysdeps/unix/sysv/linux/openat_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/openat64.c: Move __openat64_nocancel to...
* sysdeps/unix/sysv/linux/openat64_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/pause.c: Move __pause_nocancel to...
* sysdeps/unix/sysv/linux/pause_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/read.c: Move __read_nocancel to...
* sysdeps/unix/sysv/linux/read_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/waitpid.c: Move __waitpid_nocancel to...
* sysdeps/unix/sysv/linux/waitpid_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/write.c: Move __write_nocancel to...
* sysdeps/unix/sysv/linux/write_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/nios2/Makefile: Don't override
libpthread-routines.
* sysdeps/unix/sysv/linux/nios2/pt-vfork.S: New file which
defines nothing.
* sysdeps/mach/hurd/dl-sysdep.c: Define __read instead of
__libc_read, and __write instead of __libc_write. Define
__open64 in addition to __open.
There are 2 minimal strtoul implementations in ld.so:
1. __strtoul_internal in elf/dl-minimal.c.
2. tunables_strtoul in elf/dl-tunables.c.
This patch adds _dl_strtoul to replace them. Tested builds with and
without --enable-tunables.
[BZ #21528]
* elf/dl-minimal.c (__strtoul_internal): Removed.
(strtoul): Likewise.
* elf/dl-misc.c (_dl_strtoul): New function.
* elf/dl-tunables.c (tunables_strtoul): Removed.
(tunable_initialize): Replace tunables_strtoul with _dl_strtoul.
* elf/rtld.c (process_envvars): Likewise.
* sysdeps/unix/sysv/linux/dl-librecon.h (_dl_osversion_init):
Likewise.
* sysdeps/generic/ldsodefs.h (_dl_strtoul): New prototype.
This reverts commit 1f33d36a8a.
Conflicts:
elf/dl-misc.c
Also reverts the follow commits that were bug fixes to new code introduced
in the above commit:
063b2acbceb627fdd585e81c64bba1
2013-12-19 Paul Pluzhnikov <ppluzhnikov@google.com>
* elf/dl-misc.c (ptr_to_signal_safe_allocator_header): New function.
(__signal_safe_memalign, __signal_safe_free): Use it.
(__signal_safe_realloc): Likewise.
(_dl_lookup_symbol_x): Rename hash to old_hash and don't compute
value here. Compute new-style hash value. Pass new hash value
and reference to variable with the old value to do_lookup_x.
(_dl_setup_hash): If DT_GNU_HASH is defined, use it and not
old-style hash table.
(_dl_debug_bindings): Pass new hash value and reference to variable
with the old value to do_lookup_x.
* elf/do-lookup.h (do_lookup_x): Accept additional parameter with
new-style hash value and change old-style hash value parameter to
be a reference. Reoganize functions to determine whether
new-style hash table is available. Only fall back on old-style
table. If old-style hash value is needed, compute it here.
* elf/dynamic-link.h (elf_get_dynamic_info): Relocate DT_GNU_HASH
entry.
* elf/elf.h: Define SHT_GNU_HASH, DT_GNU_HASH, DT_TLSDEC_PLT,
DT_TLSDEC_GOT. Adjust DT_ADDRNUM.
* include/link.h (struct link_map): Add l_gnu_bitmask_idxbits,
l_gnu_shift, l_gnu_bitmask, l_gnu_buckets and l_gnu_chain_zero.
* Makeconfig: If linker supports --hash-style option add it to all
linker command lines to build DSOs.
* config.make.in: Define have-hash-style.
* configure.in: Test whether linker supports --hash-style option.
* elf/dl-misc.c (_dl_name_match_p): Make MAP parameter const.
* sysdeps/generic/ldsodefs.h: Adjust prototype.
2004-07-05 Ulrich Drepper <drepper@redhat.com>
* elf/dl-init.c: Don't define and use _dl_starting_up if
HAVE_INLINED_SYSCALLS is defined and the variable is not used.
* elf/dl-support.c: Likewise.
* elf/rtld.c: Likewise.
* elf/dl-misc.c (_dl_debug_vdprintf): Use writev syscall directly
if HAVE_INLINED_SYSCALLS is defined.
* sysdeps/powerpc/powerpc64/dl-machine.h: Don't rest _dl_starting_up
here.
* sysdeps/powerpc/powerpc32/dl-start.S: Likewise.
* sysdeps/unix/sysv/linux/configure.in: Define HAVE_INLINED_SYSCALLS.
* config.h.in: Add entry for HAVE_INLINED_SYSCALLS.
* sysdeps/posix/profil.c: If compiled for ld.so, omit code which
is needed to stop profiling.
* elf/dl-open.c (dl_open_worker): If a newly opened object is to be
profile make sure it cannot be unloaded.
* sysdeps/unix/sysv/linux/dl-origin.c: Inline readlink syscall.
* sysdeps/unix/sysv/linux/fcntl.c: If compiled without cancellation
support, make sure the helper function is inlined.
* sysdeps/unix/sysv/linux/pread.c: Likewise.
* sysdeps/unix/sysv/linux/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/i386/fcntl.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Likewise.
* sysdeps/generic/ldsodefs.h (struct rtld_global): Move
dl_debug_fd to rtld_global_ro.
* elf/rtld.c: Use GLRO instead of GL for dl_debug_fd.
* elf/dl-misc.c: Likewise.
(_dl_debug_vdprintf): Only take dl_load_lock if not _dl_starting_up.
* sysdeps/generic/ldsodefs.h (_dl_starting_up): Declare it here.
* sysdeps/unix/sysv/linux/init-first.c: Not here.
* sysdeps/powerpc/elf/libc-start.c: Or here.
* sysdeps/unix/sysv/aix/libc-start.c: Or here.
* sysdeps/unix/sysv/aix/start-libc.c: Or here.
* sysdeps/unix/sysv/aix/init-first.c: Or here.
* sysdeps/generic/libc-start.c: Or here.
* sysdeps/unix/sysv/linux/init-first.c (init): Protect _dl_starting_up
access with [! SHARED].
* sysdeps/unix/sysv/aix/init-first.c (init): Likewise.
changed from [USE_TLS && HAVE___THREAD].
* sysdeps/i386/dl-machine.h (elf_machine_type_class, elf_machine_rel):
Disable TLS relocs if [RTLD_BOOTSTRAP && !USE___THREAD].
* sysdeps/x86_64/dl-machine.h
(elf_machine_type_class, elf_machine_rela): Likewise.
* sysdeps/sh/dl-machine.h (elf_machine_type_class, elf_machine_rela):
Likewise.
* include/link.h (struct link_map): Remove member l_tls_tp_initialized.
* elf/rtld.c (_dl_start_final, dl_main): Don't use it.
(_dl_start): Conditionalize PT_TLS check on [USE___THREAD].
* sysdeps/i386/dl-tls.h (__TLS_GET_ADDR): Use ___tls_get_addr_internal
instead of ___tls_get_addr.
(___tls_get_addr_internal): Add attribute_hidden to decl.
* sysdeps/generic/ldsodefs.h (struct rtld_global): New variable
_dl_error_catch_tsd.
* elf/rtld.c (startup_error_tsd): New function.
(dl_main): Point _dl_error_catch_tsd at that.
* elf/dl-error.c: Don't use libc-tsd.h for DL_ERROR,
use new function pointer instead.
* elf/dl-tsd.c: New file.
* elf/Makefile (routines): Add it.
2002-10-07 Roland McGrath <roland@redhat.com>
* elf/dl-misc.c (_dl_debug_vdprintf): Use INTERNAL_SYSCALL macro for
writev if it's available. Otherwise if [RTLD_PRIVATE_ERRNO] then
take _dl_load_lock around calling __writev.
* sysdeps/unix/sysv/linux/i386/sysdep.h (INTERNAL_SYSCALL): New macro.
(INLINE_SYSCALL): Use that.
* sysdeps/generic/dl-sysdep.h: New file.
* sysdeps/mach/hurd/dl-sysdep.h: New file.
* sysdeps/generic/ldsodefs.h: Include <dl-sysdep.h>.
* include/errno.h [IS_IN_rtld]: Include <dl-sysdep.h> to define ...
[RTLD_PRIVATE_ERRNO]: Use a hidden global variable for errno and
access it directly.
* elf/dl-minimal.c (__errno_location): Removed.
* sysdeps/unix/i386/sysdep.S (__syscall_errno) [RTLD_PRIVATE_ERRNO]:
Use GOTOFF access for errno.
* sysdeps/unix/sysv/linux/i386/sysdep.h
[RTLD_PRIVATE_ERRNO] (SYSCALL_ERROR_HANDLER): Likewise.
* sysdeps/unix/x86_64/sysdep.S (__syscall_errno) [RTLD_PRIVATE_ERRNO]:
Use PC-relative access for errno.
* sysdeps/unix/sysv/linux/x86_64/sysdep.h
[RTLD_PRIVATE_ERRNO] (SYSCALL_ERROR_HANDLER): Likewise.
* include/tls.h: New file.
(USE___THREAD): New macro.
Define to 1 under [USE_TLS && HAVE___THREAD] and only when compiling
libc or libpthread.
* sysdeps/unix/sysv/linux/i386/sysdep.h [USE___THREAD]: Conditional
changed from [USE_TLS && HAVE___THREAD].
* sysdeps/unix/sysv/linux/x86_64/sysdep.h: Likewise.
* sysdeps/unix/i386/sysdep.S: Likewise.
* sysdeps/unix/x86_64/sysdep.S: Likewise.
* include/errno.h: Likewise.
* include/netdb.h: Likewise.
* include/resolv.h: Likewise.
* sysdeps/generic/errno.c: New file.
* csu/Makefile (aux): New variable, list errno.
* sysdeps/unix/sysv/linux/i386/sysdep.S (errno, _errno): Remove defns.
* sysdeps/unix/sysv/linux/m68k/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/arm/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/cris/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/hppa/sysdep.c: Likewise.
* sysdeps/unix/sysv/linux/ia64/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/sysdep.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/sh/sysdep.S: Likewise.
* sysdeps/unix/alpha/sysdep.S: Likewise.
* sysdeps/generic/start.c: Likewise.
* sysdeps/unix/start.c: Likewise.
* sysdeps/unix/arm/start.c: Likewise.
* sysdeps/unix/bsd/ultrix4/mips/start.S: Likewise.
* sysdeps/unix/sparc/start.c: Likewise.
* sysdeps/unix/sysv/irix4/start.c: Likewise.
* sysdeps/unix/sysv/linux/mips/sysdep.S: File removed.
* manual/search.texi (Tree Search Function, Hash Search Function):
Mention search.h clearly.
2002-10-05 Roland McGrath <roland@redhat.com>
* elf/dl-fxstat64.c: File removed.
* elf/dl-xstat64.c: File removed.
* elf/Makefile (rtld-routines): Remove them.
* sysdeps/unix/sysv/linux/xstat64.c: Remove RTLD_STAT64 conditionals.
Instead, use strong_alias instead of versioned_symbol in the
!SHLIB_COMPAT case.
* sysdeps/unix/sysv/linux/fxstat64.c: Likewise.
* sysdeps/unix/sysv/linux/lxstat64.c: Likewise.
* include/shlib-compat.h
(SHLIB_COMPAT): Require that IS_IN_##lib be defined nonzero.
[! NOT_IN_libc] (IS_IN_libc): Define it.
* cppflags-iterator.mk (CPPFLAGS-$(cpp-src)): Use -Dx=1 not just -Dx.
* elf/Makefile (CPPFLAGS-.os): Likewise.
* sunrpc/rpc_main.c (main): Don't declare with noreturn attribute.
Return the status instead of calling exit.
* Makeconfig (CFLAGS): Prepend -std=gnu99.
* Makerules (+make-deps): Use $(CFLAGS) only for .c sources.
Remove superfluous rm command, whose @ plus make bugs hid
all these commands from the make output.
* include/stubs-prologue.h: New file. Give #error under #ifdef _LIBC.
* Makefile ($(inst_includedir)/gnu/stubs.h): Depend on it.
Use that file's contents instead of literal echo's for the prologue.
* include/features.h: Include <gnu/stubs.h> unconditionally.
* include/gnu/stubs.h: New file.
2002-09-30 Roland McGrath <roland@redhat.com>
* elf/rtld-Rules: New file.
* elf/Makefile ($(objpfx)librtld.map, $(objpfx)librtld.mk,
$(objpfx)rtld-libc.a): New targets.
(generated): Add them.
(reloc-link): Remove -o $@ from the variable.
($(objpfx)dl-allobjs.os): Add -o $@ after $(reloc-link).
(distribute): Add rtld-Rules.
(CPPFLAGS-.os): Define this instead of CFLAGS-.os.
* Makerules ($(+sysdir_pfx)sysd-rules): Emit rules for rtld-% targets.
(common-mostlyclean, common-clean): Clean up rtld-* files.
* sysdeps/unix/make-syscalls.sh: Add rtld-*.os target name to rules.
2002-02-03 Andreas Schwab <schwab@suse.de>
* sysdeps/posix/readv.c: Use ssize_t for bytes_read.
* sysdeps/posix/writev.c: Use ssize_t for bytes_written. Fix comment.
2002-02-03 Thorsten Kukuk <kukuk@suse.de>
* sysdeps/posix/writev.c: Check for ssize_t overflow, don't use
alloca if the memory reqirements are too high.
2002-02-03 Ulrich Drepper <drepper@redhat.com>
* elf/dl-load.c (decompose_rpath): Avoid using strstr.
* elf/dl-minimal.c (_strerror_r): Use _itoa instead of _itoa_word since
the former is available anyway and speed isn't important here.
* elf/dl-misc.c (_dl_debug_vdprintf): Likewise.
* elf/dl-version.c (match_symbol): Likewise.
(_dl_check_map_versions): Likewise.
* elf/rtld.c (process_envvars): Likewise.
(print_statistics): Likewise.
* sysdeps/generic/dl-sysdep.c (_dl_show_auxv): Likewise.
* elf/dl-minimal.c (_itoa): Always define it. Make it work for all
bases. Add assert to catch uses of unimplemented features.
(__strsep): Add assert to catch uses of unimplemented features.
* elf/dl-object.c (_dl_new_object): Don't use rawmemchr. Use strchr
and avoid inline optimization.
* elf/rtld.c (process_envvars): Likewise.
* elf/dl-open.c: Don't include <stdio-common/_itoa.h>.
* elf/dl-profile.c (_dl_start_profile): Help compiler to avoid ffs.
* elf/rtld.c (dl_main): Avoid strsep inline optimization.
* stdio-common/_itoa.h: Minor simplifications of the code.
* stdio-common/_itoa.c: Likewise.
* elf/dl-reloc.c (_dl_relocate_object): Use _dl_debug_printf
instead of _dl_printf for debugging info output.
* sysdeps/mips/atomicity.h (exchange_and_add): Use branch likely.
2001-08-24 Ulrich Drepper <drepper@redhat.com>
* elf/rtld.c (print_statistics): Printf % after percent values.
* elf/dl-misc.c (_dl_debug_vdprintf): Implement %%.
* elf/dl-lookup.c (_dl_lookup_symbol): If we use the cache we
don't have to compute the hash value and initialize current_value.
Move reference_name variable to where it is needed.
(_dl_lookup_versioned_symbol): Likewise.
2001-07-06 Paul Eggert <eggert@twinsun.com>
* manual/argp.texi: Remove ignored LGPL copyright notice; it's
not appropriate for documentation anyway.
* manual/libc-texinfo.sh: "Library General Public License" ->
"Lesser General Public License".
2001-07-06 Andreas Jaeger <aj@suse.de>
* All files under GPL/LGPL version 2: Place under LGPL version
2.1.
2001-02-28 Ulrich Drepper <drepper@redhat.com>
* sysdeps/alpha/dl-machine.h (elf_machine_rela): Don't handle
relocations which are not in ld.so if RTLD_BOOTSTRAP is defined.
* sysdeps/powerpc/dl-machine.c (__process_machine_rela): Fix typo.
* elf/dl-misc.c (_dl_debug_vdprintf): Fix type visible on 64-bit
machines.
* sysdeps/unix/sysv/linux/powerpc/sysdep.h (C_TEXT): Define.