testing and real-life applications:
1) If you returned from the thread function, you got a segv instead of
calling _exit() with your return code.
2) clean up some bogus stack management. There was also an underflow
on function return.
3) when making syscalls, the kernel is expecting to have to leave space
for the function's return address. We need to duplicate this. It was
an accident that the rfork syscall actually worked here. :-/
the number of times I have given this to people and got asked: why isn't
it in libc? It is impossible to do this without assembler glue to reset
the stack for the new child process.
int rfork_thread(flags, stack_addr, start_fnc, start_arg)
int flags; Flags to rfork system call. See rfork(2).
void *stack_addr; Top of stack for thread.
int (*start_fnc)(void *); Address of thread function to call in child.
void *start_arg; Argument to pass to the thread function in child.
This is deliberately not documented or prototyped in includes until the
corresponding alpha version is written.
For libc_r renamed syscalls, correct symbol naming from
_thread_sys_foo() <-- _foo() to _thread_sys_foo() <-- _foo() <-- foo(). This
is necessary for system calls which libc_r doesn't define foo().
Some weak symbols such as poll() are defined twice. From what I understand,
depending on one weak symbol or the other to be used is a bad idea. All
such weak symbols defined in the libc_r-specific code should therefore be
made strong (non-weak?).
Simplify PSEUDO() to not define any weak symbols, since they aren't ever
needed.
alpha/SYS.h:
Correct reversed usage of WEAK_ALIAS(), which has reversed arguments from
__weak_reference(). Also, fix reversal of symbols, so that syscall foo()
is a weak alias for _foo().
Add WEAK_ALIAS() call to PRSYSCALL(), which unlike the i386 version of
PRSYSCALL(), is not defined in terms of PSYSCALL().
Make PSEUDO() equivalent to the i386 version.
just use _foo() <-- foo(). In the case of a libpthread that doesn't do
call conversion (such as linuxthreads and our upcoming libpthread), this
is adequate. In the case of libc_r, we still need three names, which are
now _thread_sys_foo() <-- _foo() <-- foo().
Convert all internal libc usage of: aio_suspend(), close(), fsync(), msync(),
nanosleep(), open(), fcntl(), read(), and write() to _foo() instead of foo().
Remove all internal libc usage of: creat(), pause(), sleep(), system(),
tcdrain(), wait(), and waitpid().
Make thread cancellation fully POSIX-compliant.
Suggested by: deischen
points. For library functions, the pattern is __sleep() <--
_libc_sleep() <-- sleep(). The arrows represent weak aliases. For
system calls, the pattern is _read() <-- _libc_read() <-- read().
Doing the "right thing" here is difficult, so create two ENTRY points for
each function (for example, __setjmp and setjmp are equivalent). This
isn't pretty, but it works for both aout and ELF.
libc symbol naming needs an overhaul in order to properly support function
wrapping, specifically in the case of a real libpthread, and these
duplicate entry points should be fixed as part of that overhaul.
Pointed out by: bde
__setjmp, __longjmp, __sigsetjmp, and __siglongjmp, respectively.
This supports cancellation in the linuxthreads port. In the long run,
a much more comprehensive solution will necessitate more dramatic changes
to libc symbol naming, and these aliases will probably need modification
at that time.
setjmp() gets the jmp_buf pointer from the wrong place (the place
where the return address is) in the shlib case, and uses it (only)
to fetch the current signal mask to address (return_address + 28).
This address is normally read-only (I hope), so the sigprocmask()
call has no effect except to return an error code.
\end{quote}
Submitted by: bde
-----------------------------
Most of the userland changes are in libc. For both the alpha
and the i386 setjmp has been changed to accomodate for the
new sigset_t. Internally, libc is mostly rewritten to use the
new syscalls. The exception is in compat-43/sigcompat.c
The POSIX thread library has also been rewritten to use the
new sigset_t. Except, that it currently only handles NSIG
signals instead of the maximum _SIG_MAXSIG. This should not
be a problem because current applications don't use any
signals higher than NSIG.
There are version bumps for the following libraries:
libdialog
libreadline
libc
libc_r
libedit
libftpio
libss
These libraries either a) have one of the modified structures
visible in the interface, or b) use sigset_t internally and
may cause breakage if new binaries are used against libraries
that don't have the sigset_t change. This not an immediate
issue, but will be as soon as applications start using the
new range to its fullest.
NOTE: libncurses already had an version bump and has not been
given one now.
NOTE: doscmd is a real casualty and has been disconnected for
the moment. Reconnection will eventually happen after
doscmd has been fixed. I'm aware that being the last one
to touch it, I'm automaticly promoted to being maintainer.
According to good taste this means that I will receive a
badge which either will be glued or mechanically stapled,
drilled or otherwise violently forced onto me :-)
NOTE: pcvt/vttest cannot be compiled with -traditional. The
change cause sys/types to be included along the way which
contains the const and volatile modifiers. I don't consider
this a solution, but more a workaround.
Submitted by: "Richard Seaman, Jr." <lists@tar.com>
Obtained from: linux :-)
Code to allow Linux Threads to run under FreeBSD.
By default not enabled
This code is dependent on the conditional
COMPAT_LINUX_THREADS (suggested by Garret)
This is not yet a 'real' option but will be within some number of hours.
to fork. It is difficult to do real vfork in libc_r, since almost every
operation with file descriptsor changes _thread_fd_table and friends.
popen(3) works much better with this change.
default syscall asm, so add it to NOASM. The other syscalls that manipulate
kernel threads use the default asm code, so they just get built
automatically.
List non-default asm sources in MDASM so that they replace the defaults.
For funny or incomplete syscalls, list them in NOASM to stop them
from getting built as defaults.
This fixes bugs in the manual handling. abs.[cS] was handled too
specially and the wrong (.c) variant for each of div.[cS], labs.[cS]
and ldiv.[cS] was added to SRCS. This caused the .c variant to be
used if `depend' was made and the .S version to be used otherwise.
The names of m-d variants are now added (manually) to MDSRCS instead
of to SRCS, and the names of all machine-independent (m-i) variants
that can reasonably be replaced by an m-d variant are now added
(manually) to MISRCS instead of to SRCS, so that a simple substitution
can be used to discard the unused m-i variants. MISRCS is potentially
all m-i sources, but the substitution is too simple to be fast, so
MISRCS should be kept reasonably small.
libc/Makefile.inc:
Do the substitution.
libc/i386/string/Makefile.inc:
Add to MDSRCS instead of to SRCS. Add the names of all sources in this
directory, but no others.
libc/string/Makefile.inc
Add to MISRCS instead of to SRCS. Add the names of all sources in this
directory. Don't use (broken) explicit rules for special cases.
so that all these makefiles can be used to build libc_r too.
Added .if ${LIB} == "c" tests to restrict man page builds to libc
to avoid needlessly building them with libc_r too.
Split libc Makefile into Makefile and Makefile.inc to allow the
libc_r Makefile to include Makefile.inc too.
the (buggy) support for alternative entry points. ALTENTRY() was only
used for memmove(). Optimizing for space was particularly silly because
memcpy() is rarely used (gcc normally inlines it).
Obtained from: NetBSD
the (buggy) support for alternative entry points. ALTENTRY() was only
used for memmove(). Optimizing for space was particularly silly because
memcpy() is rarely used (gcc normally inlines it).
Obtained from: NetBSD
- use a slightly less bogus copyright. This file was never contributed
to Berkeley. It still claims to be copright by the Regents.
- use <machine/asm.h> instead of "DEFS.h".
- use RCSID($Id$) instead of explicit assembly code and messy ifdefs.
The rcsid won't be put into the object file until we make RCSID()
non-null. NetBSD uses a LIBC_SCCS ifdef here. We used a LIBC_RCS
instead, but I want RCSID() to be controlled directly by LIBC_RCS
(actually by LIB_RCS). This is the only difference with the NetBSD
version.
- added ifdefs to support generation of memcpy() and memmove(). The
other changes are "while I'm here" to get this.
- improved style of the copy backwards case.
doesn't need to be included in files that have nothing to do with
syscalls.
Added missing `.text' to START_ENTRY so that ENTRY() works when
invoked in the data section.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
Here are the diffs for libc_r to get it one step closer to P1003.1c
These make most of the thread/mutex/condvar structures opaque to the
user. There are three functions which have been renamed with _np
suffixes because they are extensions to P1003.1c (I did them for JAVA,
which needs to suspend/resume threads and also start threads suspended).
I've created a new header (pthread_np.h) for the non-POSIX stuff.
The egrep tags stuff in /usr/src/lib/libc_r/Makefile that I uncommented
doesn't work. I think its best to delete it. I don't think libc_r needs
tags anyway, 'cause most of the source is in libc which does have tags.
also:
Here's the first batch of man pages for the thread functions.
The diff to /usr/src/lib/libc_r/Makefile removes some stuff that was
inherited from /usr/src/lib/libc/Makefile that should only be done with
libc.
also:
I should have sent this diff with the pthread(3) man page.
It allows people to type
make -DWANT_LIBC_R world
to get libc_r built with the rest of the world. I put this in the
pthread(3) man page. The default is still not to build libc_r.
also:
The diff attached adds a pthread(3) man page to /usr/src/share/man/man3.
The idea is that without libc_r installed, this man page will give people
enough info to know that they have to build libc_r.
aren't silently converted to minbrk. This stops malloc(INT_MAX) from
dumping core. Small values are still silently converted. They should
be an error. sbrk() doesn't do any range checking or conversions or
overflow checking.
Moved PIC_EPILOGUE invocation to a more natural place where it
obviously doesn't interfere with the comparison.
In a nutshell, this macroizes the local/global symbol scoping rules
that are different in a.out and ELF. It also makes the i386 assembler
stubs conform to i386 PIC calling conventions - the a.out ld.so didn't
object, but the ELF one needs it as it implements PIC jumps via PLT's as
well as calls. The a.out rtld only worked because it was accidently
snooping the grandparent calling function's return address off the stack..
This also affects the libc_r code a little, because of cpp macro nesting.
is really necessary. Going backwards on a P6 is much slower than forwards
and it's a little slower on a P5. Also moved the count mask and 'std'
down a few lines - it's a couple percent faster this way on a P5.
1) Changed LIB_SCCS and SYSLIB_SCCS to LIB_RCS and SYSLIB_RCS.
2) Changed sccsid[] variables to rcsid[]
3) Moved all RCSID strings into .text
4) Converted all SCCSID's to RCS $Id$'s
5) Added missing $Id$'s after copyright.
Embalm. Rewrite to do things much the same as gcc-2: use fistpq for speed
and elegance, and mishandle overflow consistently. __fixunsdfsi() is no
longer called by gcc.
pointer if len is 0. I should have looked at the revision history - I would
have found that Bruce already fixed the bug with len=0 over a month ago.
Whoever said that the bug was in 2.0 was wrong.
long long. Done by plugging both eax and edx with -1. This will clobber
edx unnecessarily when the return value is only 32bit...though probably
always an okay thing to do, it could stand a better fix.
This was the cause of gawk being broken (boy was THAT ever a subtle
bug!!!).
