Corinna Vinschen [Thu, 19 Aug 2021 14:08:34 +0000 (16:08 +0200)]
Cygwin: return better inode numbers for block device entries in /proc/sys
Commit 3434d35a64736f0b77a12f61784c2caa33ac44cf fixed a problem when
accessing block devices via their /proc/sys/Device entries. This
changed the way stat info is generated for these devices, resulting
in identical inode numbers for all block devices under /proc/sys/Device.
This patch fixes that by faking a device number for these devices, just as
before.
Keith Packard [Tue, 17 Aug 2021 18:51:52 +0000 (11:51 -0700)]
svfwscanf: Simplify _sungetwc_r to eliminate apparent buffer overflow
svfwscanf replaces getwc and ungetwc_r. The comments in the code talk
about avoiding file operations, but they also need to bypass the
mbtowc calls as svfwscanf operates on wchar_t, not multibyte data,
which is a more important reason here; they would not work correctly
otherwise.
The ungetwc replacement has code which uses the 3 byte FILE _ubuf
field, but if wchar_t is 32-bits, this field is not large enough to
hold even one wchar_t value. Building in this mode generates warnings
about array overflow:
In file included from ../../newlib/libc/stdio/svfiwscanf.c:35:
../../newlib/libc/stdio/vfwscanf.c: In function '_sungetwc_r.isra':
../../newlib/libc/stdio/vfwscanf.c:316:12: warning: array subscript 4294967295 is above array bounds of 'unsigned char[3]' [-Warray-bounds]
316 | fp->_p = &fp->_ubuf[sizeof (fp->_ubuf) - sizeof (wchar_t)];
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../../newlib/libc/stdio/stdio.h:46,
from ../../newlib/libc/stdio/vfwscanf.c:82,
from ../../newlib/libc/stdio/svfiwscanf.c:35:
../../newlib/libc/include/sys/reent.h:216:17: note: while referencing '_ubuf'
216 | unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */
| ^~~~~
However, the vfwscanf code *never* ungets data before the start of the
scanning operation, and *always* ungets data which matches the input
at that point, so the code always hits the block which backs up over
the input data and never hits the block which uses the _ubuf field.
In addition, the svfwscanf code will always start with the unget
buffer empty, so the ungetwc replacement never needs to support an
unget buffer at all.
Simplify the code by removing support for everything other than
backing up over the input data, leaving the check to make sure it
doesn't get underflowed in case the vfscanf code has a bug in it.
Matt Joyce [Fri, 6 Aug 2021 20:04:42 +0000 (22:04 +0200)]
libc: Added prototypes for new POSIX APIs
Added function prototypes to newlib/libc/include/pthread.h
for the following Issue 8 Standard APIs:
pthread_cond_clockwait()
pthread_mutex_clocklock()
pthread_rwlock_clockrdlock()
pthread_rwlock_clockwrlock()
The current implementation does not reliably initialize t0 once.
Additionally the initialization requires two calls to _gettimeofday().
Let's sacrifice a byte to keep the initialization status
and reduce the maximum number of calls to _gettimeofday().
This has caused issues in an application that invokes clock().
The problematic situation is as follows:
1) The program calls clock() which calls _times().
2) _gettimeofday(&t0, 0) puts 0 in t0.tv_usec (because less than 1 us has
elapsed since the beginning of time).
3) _gettimeofday(&t, 0) puts 1 in t.tv_usec (since now more than 1 us has
elapsed since the beginning of time).
4) That call to clock() returns 1 (the value from step 3 minus the value in
step 2).
5) The program does a second call to clock().
6) The code above still sees 0 in t0 so it tries to update t0 again and
_gettimeofday(&t0, 0) puts 1 in t0.tv_usec.
7) The _gettimeofday(&t, 0) puts 1 in t.tv_usec (since less than 1us has
elapsed since step 3).
8) clock() returns 0 (step 7 minus step 6) and indicates that time is
moving backwards.
Signed-off-by: Christoph Muellner <cmuellner@gcc.gnu.org>
Mark Geisert [Mon, 2 Aug 2021 06:52:31 +0000 (23:52 -0700)]
Cygwin: More profiler format + small issue fixes
Make sure to cast to ulong all DWORD values displayed with format "%lu".
More instances are fixed here than in either my earlier unused patch or
Corinna's patch. I decided to use typedef..ulong for more compact code.
Address jturney's reported small issues:
- Remove explicit external ref for cygwin_internal() as it is already
provided by <sys/cygwin.h>.
- Leave intact ref for cygwin_dll_path[] as it is required by function(s)
in path.cc that profiler uses. Added comment to that effect.
- Delete existing main() wrapper. Rename main2() to main(). This because
profiler is now a Cygwin program and doesn't need to dynamically load
cygwin1.dll.
- Documentation issues will be addressed in a separate xml patch.
(I would have linked message-ids of Corinna's and Jon's messages for
proper theading but I no longer have their original emails and the mail
archives don't show msgids any more.)
Mark Geisert [Mon, 2 Aug 2021 09:25:53 +0000 (02:25 -0700)]
Cygwin: Make gmondump conform to its doc + adjust doc
The doc for gmondump says 1 or more FILENAME are expected, but 0 is
handled. That's an oversight. Make invocation with 0 FILENAMEs print a
one-line help message.
Reword the beginning of profiler's description doc to clarify target's
child processes are run but only optionally profiled.
libc: Fix compilation for new sig2str/str2sig implementation
A recent patch introduced new code for sig2str/str2sig.
This code does not properly exclude code that requires
SIGRTMIN/SIGRTMAX to be defined and triggers the following
compile error:
Matt Joyce [Sat, 31 Jul 2021 13:22:05 +0000 (15:22 +0200)]
libc: Added implementation for sig2str/str2sig.
Added implementations for sig2str() and str2sig() in libc/signal
in order to improve POSIX compliance. Added fucntion prototypes
in libc/include/sys/signal.h.
Cygwin: getaddrinfo: return valid ai_socktype and ai_protocol values
If a service is supported as TCP and UDP service, GetAddrInfo does not
return two entries, one for TCP, one for UDP, as on Linux. Rather, it
just returns a single entry with ai_socktype and ai_protocol set to 0.
If the service only exists as TCP or UDP service, then ai->ai_socktype
is set, but ai_protocol isn't.
Fortunately we copy over the result from Windows into local storage
anyway, so this patch adds code to fix up the fields neglected by
Windows. In case ai_socktype as well as ai_protocol are 0, duplicate
the entry with valid values for ai_socktype and ai_protocol.
Ken Brown [Mon, 26 Jul 2021 14:27:53 +0000 (10:27 -0400)]
Cygwin: getifaddrs: don't return a zero IPv4 address
If an interface is disconnected, net.cc:get_ifs tries to fetch IPv4
addresses from the registry. If it fails, it currently returns
pointers to sockaddr structs with zero address. Return a NULL pointer
instead, to signal the caller of getifaddrs that we do not have a
valid struct sockaddr.
riscv64-unknown-elf-g++-11.1.0 regression suite reports the following
failures for
$ make check-gcc-c++ RUNTESTFLAGS='dg.exp=Wstringop-overflow-6.C'
```
FAIL: g++.dg/warn/Wstringop-overflow-6.C -std=gnu++14 (test for excess errors)
FAIL: g++.dg/warn/Wstringop-overflow-6.C -std=gnu++17 (test for excess errors)
FAIL: g++.dg/warn/Wstringop-overflow-6.C -std=gnu++2a (test for excess errors)
UNSUPPORTED: g++.dg/warn/Wstringop-overflow-6.C -std=gnu++98
```
The "excess errors" being
```
output is In file included from /home/maxim/prj/riscv-upstream/install/riscv64-unknown-elf/include/wchar.h:6,
from /home/maxim/prj/riscv-upstream/build/gcc-stage2/riscv64-unknown-elf/libstdc++-v3/include/cwchar:44,
from /home/maxim/prj/riscv-upstream/build/gcc-stage2/riscv64-unknown-elf/libstdc++-v3/include/bits/postypes.h:40,
from /home/maxim/prj/riscv-upstream/build/gcc-stage2/riscv64-unknown-elf/libstdc++-v3/include/iosfwd:40,
from /home/maxim/prj/riscv-upstream/build/gcc-stage2/riscv64-unknown-elf/libstdc++-v3/include/ios:38,
from /home/maxim/prj/riscv-upstream/build/gcc-stage2/riscv64-unknown-elf/libstdc++-v3/include/ostream:38,
from /home/maxim/prj/riscv-upstream/build/gcc-stage2/riscv64-unknown-elf/libstdc++-v3/include/iostream:39,
from /home/maxim/prj/riscv-upstream/gcc-11.1.0/gcc/testsuite/g++.dg/warn/Wstringop-overflow-6.C:6:
/home/maxim/prj/riscv-upstream/install/riscv64-unknown-elf/include/sys/reent.h:685:11: warning: unnecessary parentheses in declaration of '_sig_func' [-Wparentheses]
```
David Allsopp [Tue, 20 Jul 2021 15:07:00 +0000 (16:07 +0100)]
Ensure nanosleep(2) never returns negative rem
It appears to be the case that NtQueryTimer can return a negative time
remaining for an unsignalled timer. The value appears to be less than
the timer resolution.
Signed-off-by: David Allsopp <david.allsopp@metastack.com>
Kito Cheng [Mon, 19 Jul 2021 08:50:22 +0000 (16:50 +0800)]
libm: Fixing overflow handling issue for scalbnf and scalbn
cc Aldy Hernandez <aldyh@redhat.com> and Andrew MacLeod <amacleod@redhat.com>,
they are author of new VRP analysis for GCC, just to make sure I didn't
mis-understanding or mis-interpreting anything on GCC site.
GCC 11 have better value range analysis, that give GCC more confidence
to perform more aggressive optimization, but it cause scalbn/scalbnf get
wrong result.
Using scalbn to demostrate what happened on GCC 11, see comments with VRP
prefix:
```c
double scalbn (double x, int n)
{
/* VRP RESULT: n = [-INF, +INF] */
__int32_t k,hx,lx;
...
k = (hx&0x7ff00000)>>20;
/* VRP RESULT: k = [0, 2047] */
if (k==0) {
/* VRP RESULT: k = 0 */
...
k = ((hx&0x7ff00000)>>20) - 54;
if (n< -50000) return tiny*x; /*underflow*/
/* VRP RESULT: k = -54 */
}
/* VRP RESULT: k = [-54, 2047] */
if (k==0x7ff) return x+x; /* NaN or Inf */
/* VRP RESULT: k = [-54, 2046] */
k = k+n;
if (k > 0x7fe) return huge*copysign(huge,x); /* overflow */
/* VRP RESULT: k = [-INF, 2046] */
/* VRP RESULT: n = [-INF, 2100],
because k + n <= 0x7fe is false, so:
1. -INF < [-54, 2046] + n <= 0x7fe(2046) < INF
2. -INF < [-54, 2046] + n <= 2046 < INF
3. -INF < n <= 2046 - [-54, 2046] < INF
4. -INF < n <= [0, 2100] < INF
5. n = [-INF, 2100] */
if (k > 0) /* normal result */
{SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;}
if (k <= -54) {
/* VRP OPT: Evaluate n > 50000 as true...*/
if (n > 50000) /* in case integer overflow in n+k */
return huge*copysign(huge,x); /*overflow*/
else return tiny*copysign(tiny,x); /*underflow*/
}
k += 54; /* subnormal result */
SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20));
return x*twom54;
}
```
However give the input n = INT32_MAX, k = k+n will overflow, and then we
expect got `huge*copysign(huge,x)`, but new VRP optimization think
`n > 50000` is never be true, so optimize that into `tiny*copysign(tiny,x)`.
so the solution here is to moving the overflow handle logic before `k = k + n`.
Mark Geisert [Fri, 16 Jul 2021 04:49:57 +0000 (21:49 -0700)]
Cygwin: updates to wire in profiler, gmondump
These are updates to wire into the build tree the new tools profiler and
gmondump, and to supply documentation for the tools.
The documentation for profiler and ssp now mention each other but do not
discuss their similarities or differences. That will be handled in a
future update to the "Profiling Cygwin Programs" section of the Cygwin
User's Guide, to be supplied.
Mark Geisert [Fri, 16 Jul 2021 04:49:56 +0000 (21:49 -0700)]
Cygwin: New tool: gmondump
This new tool was formerly part of 'profiler' but was spun out thanks to
Jon T's reasonable review comment. Gmondump is more of a debugging tool
than something users might have need for. Users would more likely use
gprof to make use of symbolic info like function names and source line
numbers.
Mark Geisert [Fri, 16 Jul 2021 04:49:55 +0000 (21:49 -0700)]
Cygwin: New tool: profiler
The new tool formerly known as cygmon is renamed to 'profiler'. For the
name I considered 'ipsampler' and could not think of any others. I'm open
to a different name if any is suggested.
I decided that a discussion of the pros and cons of this profiler vs the
existing ssp should probably be in the "Profiling Cygwin Programs" section
of the Cygwin User's Guide rather than in the help for either. That
material will be supplied at some point.
CONTEXT buffers are made child-specific and thus thread-specific since
there is one profiler thread for each child program being profiled.
The SetThreadPriority() warning comment has been expanded.
chmod() works on Cygwin so the "//XXX ineffective" comment is gone.
I decided to make the "sample all executable sections" and "sample
dynamically generated code" suggestions simply expanded comments for now.
The profiler program is now a Cygwin exe rather than a native exe.
Ken Brown [Sun, 11 Jul 2021 11:04:58 +0000 (07:04 -0400)]
Cygwin: cfsetspeed: allow speed to be a numerical baud rate
The Linux man page for cfsetspeed(3) specifies that the speed argument
must be one of the constants Bnnn (e.g., B9600) defined in termios.h.
But Linux in fact allows the speed to be the numerical baud rate
(e.g., 9600). For consistency with Linux, we now do the same.
Kito Cheng [Mon, 12 Jul 2021 09:17:21 +0000 (17:17 +0800)]
Minimal support for ISO/IEC TS 18661-3.
- GCC will set __FLT_EVAL_METHOD__ to 16 if __fp16 supported, e.g.
cortex-a55/aarch64.
- $ aarch64-unknown-elf-gcc -v 2>&1 |grep version
gcc version 9.2.0 (GCC)
- $ aarch64-unknown-elf-gcc -E -dM -mcpu=cortex-a55 - < /dev/null |grep FLT_EVAL_METHOD
#define __FLT_EVAL_METHOD__ 16
#define __FLT_EVAL_METHOD_TS_18661_3__ 16
#define __FLT_EVAL_METHOD_C99__ 16
- The behavior of __FLT_EVAL_METHOD__ == 16 is same as
__FLT_EVAL_METHOD__ == 0 except for float16_t, but newlib didn't
support float16_t.
Jon Turney [Thu, 20 May 2021 17:28:01 +0000 (18:28 +0100)]
Cygwin: Define PSAPI_VERSION as 1 before including psapi.h
The default PSAPI_VERSION is controlled by WIN32_WINNT, which we set to
0x0a00 when building utils since 48a76190 (and is the default in w32api
>= 9.0.0)
In order for the built executables to run on Windows Vista, we must also
define PSAPI_VERSION as 1 (otherwise '#define GetModuleFileNameExA
K32GetModuleFileNameExA' causes a 'The procedure entry point
K32GetModuleFilenameExA could not be located in the dynamic link library
kernel32.dll' error at run time).
Also drop uneeded psapi.h from dlfcn.cc (31ddf45d), resource.cc
(34a6eeab) and ps.cc (1def2148).
Jon Turney [Mon, 14 Jun 2021 12:51:41 +0000 (13:51 +0100)]
Cygwin: Use cmdsynopsis element in utils documentation
Use <cmdsynopsis> element markup in utils docbook documentation, rather
than some preformatted text inside <screen>.
(This didn't happen as part of 646745cb, when we first started using
refentry elements to make it possible to generate manpages)
This helps produce better looking manpages:
* uses bold (for command names) and italic (for replaceable items)
* different output formats inconsistently treat tabs inside <screen>
(so we have to be careful to not use them in that preformatted text)
Also clean up various issues:
* Replace '[OPTIONS]' with a real synopsis of the options
* Consistently use 'ITEM...' rather than 'ITEM1 [ITEM2...]' for an item
which should appear 1 or more times (cygcheck -f, getfacl, kill)
* Consistently document the '-h | -V' invocation form
* Since replaceable items are now marked up so they have some formatting
indicating they are replaceable, we can drop wrapping them in angle
brackets, as is done in some places
* Add missing '-W' and '-p PID' options to ps synopsis
* Adjust cygpath synopsis to show that only one 'System information'
option is allowed, possibly modified by -A
Future work:
* Sync up the actual help emitted by the util, where it's been improved
* Also don't use <screen> for formatting 'OPTIONS' section of manpage
* pldd inconsistently uses '-?' rather than '-h'!
Jon Turney [Mon, 14 Jun 2021 20:18:49 +0000 (21:18 +0100)]
Cygwin: Various minor fixes to utils documentation
* Drop duplicate 'Options:' headers (mkgroup, mkpassword)
* Add missing indication that MACHINE is optional with -L (mkgroup, mkpassword)
* Tweak some <refpurpose> which try to be a synopsis, rather than a decription (passwd, ssp)
* Drop some stray '\n' in setfacl options
* Move 'Original Author' note in ssp to an AUTHORS section
* Use <para> to improve formatting of tzset manpage
Keith Packard [Tue, 22 Jun 2021 17:26:26 +0000 (10:26 -0700)]
stdlib: Make strtod/strtof set ERANGE consistently for underflow.
The C standard says that errno may acquire the value ERANGE if the
result from strtod underflows. According to IEEE 754, underflow occurs
whenever the value cannot be represented in normalized form.
Newlib is inconsistent in this, setting errno to ERANGE only if the
value underflows to zero, but not for denorm values, and never for hex
format floats.
This patch attempts to consistently set errno to ERANGE for all
'underflow' conditions, which is to say all values which are not
exactly zero and which cannot be represented in normalized form.
This matches glibc behavior, as well as the Linux, Mac OS X, OpenBSD,
FreeBSD and SunOS strtod man pages.
Thomas Wolff [Fri, 2 Jul 2021 22:00:00 +0000 (00:00 +0200)]
tty/pty: support TIOCSWINSZ pixel-size-only change notification
xterm 368 and mintty 3.5.1 implement a new feature to support
notification of terminal scaling via font zooming also if the terminal
text dimensions (rows/columns) stay unchanged, using
ioctl(TIOCSWINSZ), raising SIGWINCH;
this patches cygwin to support that scenario
Jeremy Drake [Sat, 29 May 2021 18:48:11 +0000 (11:48 -0700)]
Cygwin: respect PC_SYM_FOLLOW and PC_SYM_NOFOLLOW_REP with inner links.
The new GetFinalPathNameW handling for native symlinks in inner path
components is disabled if caller doesn't want to follow symlinks, or
doesn't want to follow reparse points.
Jeff Law [Tue, 6 Jul 2021 14:46:09 +0000 (10:46 -0400)]
Fix builds on iq2000 and visium
visium and iq2000 have libgloss configure bits that reference
target_makefile_frag, but it's never set. This leads to failures during the
configure process and an empty libgloss/<target>/Makefile. Naturally bad
things happen with an empty Makefile.
This patch initializes target_makefile_frag for both targets in their
configure.in files and updates the generated configure files. This fixes the
build failures. I've been using it in my tester for about a week and both
targets have flipped from consistently failing to consistently passing.
These have been defined incorrectly, as per specification and CPU
implementations SXE is bit 6 and UXE is bit 7. This was noticed when
tracking down our test suite mmu test failures.
Test Suite: https://github.com/openrisc/or1k-tests/blob/master/native/or1k/or1k-mmu.c#L68-L72
Spec: https://raw.githubusercontent.com/openrisc/doc/master/openrisc-arch-1.3-rev1.pdf
See section 8.4.8 Instruction Translation Lookaside Buffer Way y Translate
Registers where these are defined.
Binutils LD default linker script was recently fixed to allow memory
sizes to be set via command line. Use this feature to remove the special
sim linker script in libgloss.
It is acceptable to require newer Binutils version here because simulator
target is only used for regression testing the toolchain. Real HW
targets are not affected.
Jeff Johnston [Fri, 4 Jun 2021 18:36:38 +0000 (14:36 -0400)]
Fix rounding issues with sqrt/sqrtf
- compiler is sometimes optimizing out the rounding check in
e_sqrt.c and ef_sqrt.c which uses two constants to create
an inexact operation
- there is a similar constant operation in s_tanh.c/sf_tanh.c
- make the one and tiny constants volatile to stop this
Richard Earnshaw [Wed, 26 May 2021 14:17:11 +0000 (15:17 +0100)]
aarch64: support binary mode for opening files
Newlib for aarch64 uses libgloss for the backend. One common libgloss
implementation is the 'rdimon' implementation, which uses the Arm
Semihosting protocol. In order to support a remote host that runs on
Windows we need to know whether a file is to be opened in binary or
text mode. That means that we need to preserve this information via
O_BINARY until we know what the libgloss binding will be.
This patch simply copies the arm implementation from sys/arm/sys and
puts it in machine/aarch64/sys, because we don't have a 'sys' subtree
on aarch64.
Corinna Vinschen [Tue, 25 May 2021 20:03:36 +0000 (22:03 +0200)]
Cygwin: path_conv: fix mqueue path check
The check for a file or dir within /dev/mqueue is accidentally using
the incoming path, which could be a relative path. Make sure to
restore the absolute POSIX path in path_copy and only then test the
path.
Also, move the actual check for a valid path below /dev/mqueue into
the fhandler_mqueue class.
Corinna Vinschen [Tue, 25 May 2021 19:46:13 +0000 (21:46 +0200)]
Cygwin: cwdstuff: check if /dev exists
/dev has been handled as virtual dir in cwdstuff, thus not allowing
to start native apps from /dev as CWD, even if /dev actually exists
on disk. Unfortunately this also affects Cygwin executables started
from a debugger.
When chdir'ing to /dev, check if /dev exists on disk. If so, treat
it as any other existing path.
reuse fhandler_virtual implementation to implement read and lseek.
The output from read(2) is modelled after the output when reading
from an mq file on Linux.
Corinna Vinschen [Tue, 25 May 2021 18:15:16 +0000 (20:15 +0200)]
Cygwin: POSIX msg queues: move all mq_* functionality into fhandler_mqueue
The POSIX entry points are just wrappers now, calling into
fhandler_mqueue. While at it, eliminate mqi_flags, replace with
standard fhandler nonblocking flag.
Corinna Vinschen [Tue, 25 May 2021 14:49:04 +0000 (16:49 +0200)]
Cygwin: POSIX msg queues: implement open/mq_open entirely in fhandler
The mq_open call is just a framework now. This patch moves the
entire functionality into fhandler_mqueue. To support standard
OS calls (as on Linux), make fhandler_mqueue a derived class from
fhandler_disk_file and keep the base handle the handle to the
default stream, to allow implementing O_PATH functionlaity as well
as reading from the file and NOT reading binary message queue data.
Implement a standard fhandler_mqueue::open method, allowing, for
instance, to touch a file under /dev/mqueue and if it doesn't exist,
to create a message queue file.
FIXME: This introduces a BAD HACK into path_conv::check, which needs
reviewing.
Keep the posix path intact in the fhandler, and change get_proc_fd_name
accordingly to return only the basename plus leading slash for
/proc/<PID>/fd.
Corinna Vinschen [Tue, 25 May 2021 14:24:58 +0000 (16:24 +0200)]
Cygwin: get_nt_native_path: allow to append suffix
POSIX message queues will be moved into NTFS streams.
Extend get_nt_native_path to provide a filename suffix which is not
subject to special character transposition, to allow specifying
a colon.
Corinna Vinschen [Fri, 21 May 2021 13:21:29 +0000 (15:21 +0200)]
Cygwin: POSIX ipc: fix evaluation of naming rules
The function evaluating correctness of ipc object names was a
bit half-hearted. Fix the tests to follow more closely the
desriptions in the Linux man pages.
Corinna Vinschen [Fri, 21 May 2021 10:01:56 +0000 (12:01 +0200)]
Cygwin: POSIX msg queues: Convert mqd_t to a descriptor
So far, the mqd_t type returned a pointer to an allocated
area under the hood. The mutex and event objects attached
to the message queue were implemented as inheritable types.
As unfortunate side effect the HANDLEs to these objects
were inherited by exec'd child processes, even though all
other message queue properties are not inherted, per POSIX.
Fix this by converting an mqd_t to a descriptor, and create a
matching fhandler_mqueue object to handle various aspects of
the message queues inside the fhandler. Especially, create the
IPC objects as non-inheritable and duplicate the HANDLEs as
part of the fixup_after_fork mechanism.
Drop using mmap and create the memory map with NT functions.
This allows to control duplication of handle and mapping in the
forked child process, without the requirement to regenerate the
map in the same spot. It also allows to dup() the descriptor,
as on Linux, albeit this isn't implemented yet.
This patch is the first cut. There's a bit more to do, like
moving more functionality from the POSIX functions into the
fhandler and making sure the mqd_t type can't be used in other
descriptor-related functions willy-nilly.
git://sourceware.org / newlib-cygwin.git / log