Previously, libc.so would initialize its notion of the break address
using _end, a special symbol emitted by the static linker following
the bss section. Compatibility issues between lld and ld.bfd could
cause the wrong definition of _end (libc.so's definition rather than
that of the executable) to be used, breaking the brk()/sbrk()
interface.
Avoid this problem and future interoperability issues by simply not
relying on _end. Instead, modify the break() system call to return
the kernel's view of the current break address, and have libc
initialize its state using an extra syscall upon the first use of the
interface. As a side effect, this appears to fix brk()/sbrk() usage
in executables run with rtld direct exec, since the kernel and libc.so
no longer maintain separate views of the process' break address.
PR: 228574
Reviewed by: kib (previous version)
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D15663
Originally, on the VAX exect() enable tracing once the new executable
image was loaded. This was possible because tracing was controllable
through user space code by setting the PSL_T flag. The following
instruction is a system call that activated tracing (as all
instructions do) by copying PSL_T to PSL_TP (trace pending). The
first instruction of the new executable image would trigger a trace
fault.
This is not portable to all platforms and the behavior was replaced with
ptrace(PT_TRACE_ME, ...) since FreeBSD forked off of the CSRG repository.
Platforms either incorrectly call execve(), trigger trace faults inside
the original executable, or do contain an implementation of this
function.
The exect() interfaces is deprecated or removed on NetBSD and OpenBSD.
Submitted by: Ali Mashtizadeh <ali@mashtizadeh.com>
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D14989
These files are identical to the generated system calls.
In the case of MIPS, the file was already disconnected from the build.
Submitted by: Ali Mashtizadeh <ali@mashtizadeh.com>
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D14976
The arm, mips, and riscv MD Symbol.map files listed some (but not all)
of the softfloat symbols that were actually defined in softfloat.c.
While here, also remove entries for __fixuns[sd]fsi which are provided
by libcompiler_rt and not by libc.
Sponsored by: DARPA / AFRL
The GP register can be clobbered by the callback, so save it in S1
while invoking the callback function.
While here, add a comment expounding on the treatment of GP for the
various ABIs and the assumptions made.
Reviewed by: jmallett (earlier version)
Sponsored by: DARPA / AFRL
Differential Revision: https://reviews.freebsd.org/D14179
This implementation spills additional arguments on the stack so works
fine with more than 6 arguments. I believe the check was just copied
over from sparc64 (which doesn't support spilling onto the stack)
Sponsored by: DARPA / AFRL
- Add a new <machine/abi.h> header to hold constants shared between C
and assembly such as CALLFRAME_SZ.
- Add a new STACK_ALIGN constant to <machine/abi.h> and use it to
replace hardcoded constants in the kernel and makecontext(). As a
result of this, ensure the stack pointer on N32 and N64 is 16-byte
aligned for N32 and N64 after exec(), after pthread_create(), and
when sending signals rather than 8-byte aligned.
Reviewed by: jmallett
Sponsored by: DARPA / AFRL
Differential Revision: https://reviews.freebsd.org/D13875
- N32 and N64 do not have a $a0-3 gap.
- Use 'sp += 4' to skip over the gap for O32 rather than '+= i'. It
doesn't make a functional change, but makes the code match the comment.
Sponsored by: DARPA / AFRL
It would previously return negative zero for -0.0 since -0.0 does not
compare less than 0. The issue was discovered when running the libc++
test suite on softfloat MIPS64.
I have verified that both clang and GCC generate sensible code for the
builtin. For soft float they clear the sign bit using integer operations
and in hard float mode they use abs.d.
Reviewed by: #mips, jhb, brooks, imp, emaste
Approved by: jhb (mentor)
Differential Revision: https://reviews.freebsd.org/D13135
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
Initially, only tag files that use BSD 4-Clause "Original" license.
RelNotes: yes
Differential Revision: https://reviews.freebsd.org/D13133
These builtins were listed in the mips-specific Symbol.map for libc but
were not implemented. Compiling mips with recent clang requires these
symbols.
Sponsored by: DARPA / AFRL
D8376 extended softfloat/hardfloat support, but used a macro that never
actually gets set except in libc and msun's Makefile.inc. So libc and libm
got built correctly, but any program including fenv.h itself assumed it was
on a hardfloat systen and emitted inline fpu instructions for
fedisableexcept() and friends.
Using __mips_soft_float makes everything work in all cases, since it's a
compiler-internal macro that is always set correctly for the target
PR: 217845
Submitted by: Dan Nelson <dnelson_1901@yahoo.com>
MFC after: 1 week
MDSRCS it intended to allow assembly versions of funtions with C
implementations listed in MISRCS. The selection of the correct
machdep_ldis?.c for a given architecture does not follow this pattern
and the file should be added to SRCS directly.
Reviewed by: emaste, imp, jhb
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9841
- Remove .c files which duplicate entries in MISRCS.
- Use the same, less merge conflict prone style in all cases.
- Use MDSRCS for mips (.c and .S files both ended up in SRCS).
- Remove pointless sparc64 Makefile.inc.
- Remove uninformative foreign VCS ID entries.
Reviewed by: emaste, imp, jhb
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9841
The initial value of NOASM is nearly the same in all cases and the
initial value of PSEUDO is the same in all cases so reduce duplication
(and hopefully, future merge conflicts) by machine independent defaults.
Also document the PSEUDO variable.
Reviewed by: jhb, kib
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D7820
Besides removing hand-translation to assembler, this also adds missing
wrappers for arm64 and risc-v.
Reviewed by: emaste, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D7694
value.
This eliminates the need for machine dependant assembly wrappers for
pipe(2).
It also make passing an invalid address to pipe(2) return EFAULT rather
than triggering a segfault. Document this behavior (which was already
true for pipe2(2), but undocumented).
Reviewed by: andrew
Approved by: re (gjb)
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D6815
i386 stopped exporting .cerror in r240152, and likewise for amd64 in
r240178. It is not used by other libraries on any platform, so apply
the same change to the remaining architectures.
Reviewed by: jhibbits, jilles
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5774
They are not used anywhere else in the base system and are an internal
implementation detail that does not need to be exposed.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5728
The PSEUDO* macros should not declare <syscall>, only _<syscall> and
__sys_<syscall>. This was causing the interposing C wrappers to be
ignored due to link order.
Reviewed by: kib
Obtained from: CheriBSD (4e8e13c90fc6a80e1520de44a6864cfd78b3b56d)
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D4097
The arm version hasn't been used in ages.
The mips version uses a valid, but pointless check of v1 and has been
unhooked from the build since r276630.
Differential Revision: https://reviews.freebsd.org/D2592
Reviewed by: emaste
Sponsored by: DARPA, AFRL
pwrite(2) syscalls are wrapped to provide compatibility with pre-7.x
kernels which required padding before the off_t parameter. The
fcntl(2) contains compatibility code to handle kernels before the
struct flock was changed during the 8.x CURRENT development. The
shims were reasonable to allow easier revert to the older kernel at
that time.
Now, two or three major releases later, shims do not serve any
purpose. Such old kernels cannot handle current libc, so revert the
compatibility code.
Make padded syscalls support conditional under the COMPAT6 config
option. For COMPAT32, the syscalls were under COMPAT6 already.
Remove WITHOUT_SYSCALL_COMPAT build option, which only purpose was to
(partially) disable the removed shims.
Reviewed by: jhb, imp (previous versions)
Discussed with: peter
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
It seems GAS makes the substitution automatically, but Clang's
integrated assembler does not (yet). It fails with "invalid operand for
instruction."
Reported by: sbruno
Only i386 and amd64 provide a non-trivial __getcontextx(). Use a common
trivial implementation in gen/ for other architectures, rather than
copying the file to each MD subdirectory.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1472
This change saves/restores the callee-saved MIPS floating point
registers as documented by the o32/n32/n64 spec ("MIPSpro N32
ABI Handbook", Table 2-1) for the _setjmp(3), _longjmp(3),
setjmp(3) and longjmp(3) C library functions. This is only
included when the C library is built with hardware floating point
support (or when "SOFTFLOAT" is not defined).
Submitted by: sson
MFC after: 1 month
Sponsored by: DARPA, AFRL
This includes:
o All directories named *ia64*
o All files named *ia64*
o All ia64-specific code guarded by __ia64__
o All ia64-specific makefile logic
o Mention of ia64 in comments and documentation
This excludes:
o Everything under contrib/
o Everything under crypto/
o sys/xen/interface
o sys/sys/elf_common.h
Discussed at: BSDcan
if not already defined. This allows building libc from outside of
lib/libc using a reach-over makefile.
A typical use-case is to build a standard ILP32 version and a COMPAT32
version in a single iteration by building the COMPAT32 version using a
reach-over makefile.
Obtained from: Juniper Networks, Inc.
Per the NetBSD Foundation statement
Third parties are encouraged to change the license on any files which
have a 4-clause license contributed to the NetBSD Foundation to a
2-clause license.
check_deferred_signal() returns twice, since handle_signal() emulates
the return from the normal signal handler by sigreturn(2)ing the
passed context. Second return is performed on the destroyed stack
frame, because __fillcontextx() has already returned. This causes
undefined and bad behaviour, usually the victim thread gets SIGSEGV.
Avoid nested frame and the need to return from it by doing direct call
to getcontext() in the check_deferred_signal() and using a new private
libc helper __fillcontextx2() to complement the context with the
extended CPU state if the deferred signal is still present.
The __fillcontextx() is now unused, but is kept to allow older
libthr.so to be used with the new libc.
Mark __fillcontextx() as returning twice [1].
Reported by: pgj
Pointy hat to: kib
Discussed with: dim
Tested by: pgj, dim
Suggested by: jilles [1]
MFC after: 1 week
but use normal references instead of weak. This makes the statically
linked binaries to use fast gettimeofday(2) by forcing the linker to
resolve references and providing the neccessary functions.
Reported by: bde
Tested by: marius (sparc64)
MFC after: 2 weeks
fit into existing mcontext_t.
On i386 and amd64 do return the extended FPU states using
getcontextx(3). For other architectures, getcontextx(3) returns the
same information as getcontext(2).
Tested by: pho
MFC after: 1 month
This allows people to still write statically linked applications that
call strchr() or strrchr() and have a local variable or function called
index.
Discussed with: bde@
As I looked through the C library, I noticed the FreeBSD MIPS port has a
hand-written version of index(). This is nice, if it weren't for the
fact that most applications call strchr() instead.
Also, on the other architectures index() and strchr() are identical,
meaning we have two identical pieces of code in the C library and
statically linked applications.
Solve this by naming the actual file strchr.[cS] and let it use
__strong_reference()/STRONG_ALIAS() to provide the index() routine. Do
the same for rindex()/strrchr().
This seems to make the C libraries and static binaries slightly smaller,
but this reduction in size seems negligible.
working MI one. The MI one only needs to be overridden on machines
with non-IEEE754 arithmetic. (The last supported one was the VAX.)
It can also be overridden if someone comes up with a faster one that
actually passes the regression tests -- but this is harder than it sounds.
The existing implementation of bzero incorrectly clears bytes when the
start address is not word aligned. Fix it by using REG_SHI macro which
works on both 32 and 64 bit.
Submitted by: Artem Belevich (fbsdlist at src cx)
