lock: Avoid use of undefined DISPATCH_INTERNAL_CRASH 

build: add a cmake based build system

(Radar 31585625)

tests: adjust printf for size types

Use the z modifier for the size_t type conversion in printf specifiers.

libdispatch: Avoid submodules for headers that should not be included

libdispatch has an umbrella header, dispatch.h, that should be used for
including all of the other headers.  This is enforced via
__DISPATCH_INDIRECT__.

Since it isn't legal to include one of the other headers on their own,
it isn't logical to have submodules for them.  Moreover, submodules
*should* have local visibility (be unaware of the context they're
included from); meaning that __DISPATCH_INDIRECT__ will never be
defined.

Logically, all of the headers are part of a single module/interface.

Patch by me & Duncan P. Exon Smith

Fix compile error on s390x in shims/lock.h

Building swift-corelibs-libdispatch on powerpc64le under Linux lead to
the following build failure:

	/bin/bash ../libtool  --tag=CXX   --mode=compile /home/ubuntu/swift-dev/build/buildbot_incremental/llvm-linux-powerpc64le/bin/clang++ -DHAVE_CONFIG_H -I. -I../config  -I.. -I.. -I../private -DDISPATCH_USE_DTRACE=0 -I../libpwq/include -Wall -fvisibility=hidden -momit-leaf-frame-pointer  -isystem /usr/include/bsd -DLIBBSD_OVERLAY  -fblocks -I../src/BlocksRuntime -std=gnu++11 -fno-exceptions -O2 -c -o libdispatch_la-block.lo `test -f 'block.cpp' || echo './'`block.cpp
	libtool: compile:  /home/ubuntu/swift-dev/build/buildbot_incremental/llvm-linux-powerpc64le/bin/clang++ -DHAVE_CONFIG_H -I. -I../config -I.. -I.. -I../private -DDISPATCH_USE_DTRACE=0 -I../libpwq/include -Wall -fvisibility=hidden -momit-leaf-frame-pointer -isystem /usr/include/bsd -DLIBBSD_OVERLAY -fblocks -I../src/BlocksRuntime -std=gnu++11 -fno-exce
	ptions -O2 -c block.cpp  -fPIC -DPIC -o .libs/libdispatch_la-block.o
	In file included from block.cpp:32:
	In file included from ./internal.h:628:
	In file included from ./shims.h:171:
	./shims/lock.h:550:3: error: use of undeclared identifier 'DISPATCH_INTERNAL_CRASH'
			DISPATCH_INTERNAL_CRASH(errno, "sys_membarrier not supported");
			^
	1 error generated.
	Makefile:701: recipe for target 'libdispatch_la-block.lo' failed
	make[2]: *** [libdispatch_la-block.lo] Error 1
	make[2]: Leaving directory '/home/ubuntu/swift-dev/swift-corelibs-libdispatch/src'
	Makefile:541: recipe for target 'all' failed
	make[1]: *** [all] Error 2
	make[1]: Leaving directory '/home/ubuntu/swift-dev/swift-corelibs-libdispatch/src'
	Makefile:457: recipe for target 'all-recursive' failed
	make: *** [all-recursive] Error 1

Include ordering in internal.h is tightly constrained, so open-code the macro
to avoid the dependency problem.
Signed-off-by: Andrew Jeffery andrew@aj.id.au>

Fix compile error on s390x in shims/lock.h.  s390x has a strong memory model and does not require membarrier.

Makes the DispatchIO initializer that accepts a path failable, reflecting the fact that a relative or non-existent path is invalid.

(Radar 31115994)

(Radar 30699743)

(Radar rdar://problem/30518517)

This is far from complete, but is sufficient to build a Linux version of
libdispatch.  It shows what a potential cmake based build system could
look like, and if desired can be completed to build all the various
flavours with cmake.

SR-4026: dispatch_test_check_evfilt_read_for_fd for epoll

fixes for compiler warnings

Collection of small fixes to eliminate compiler
warnings when building libdispatch and its tests.

queue_specific_queue is missing its do_push vtable entry

Implement dispatch_test_check_evfilt_read_for_fd test method
for the event_epoll backend.

Also reorder all vtable entries to be in the same order (push, invoke,
wakeup).

Reenable dispatch_context_for_key.

SR: SR-4039

remove unused dependency on linux/membarrier.h for intel to fix CI build

add dependency on linux-libc-dev to INSTALL.md for other architectures

Temporarily move dispatch_context_for_key test into the unreliable tests

temporarily move dispatch_context_for_key test into the unreliable tests since it started failing in the CI

provide fallback definitions for all API_* macros

Merge darwin/libdispatch-806 to master and apply Linux build fixes

Linux fixes for dispatch-806 merge

Collection of small fixes to dispatch-806 merge to
allow code to compile/link/run on Linux.

Signed-off-by: Daniel A. Steffen dsteffen@apple.com>

Signed-off-by: Daniel A. Steffen dsteffen@apple.com>

Signed-off-by: Daniel A. Steffen dsteffen@apple.com>

Remove unused include of sys/user.h
Signed-off-by: Daniel A. Steffen dsteffen@apple.com>

The include of sys/user.h is not needed; it
is a leftover from the initial linux port.
Eliminating it avoids a build problem for
the Swift dispatch overlay on ubuntu 14.04
powerpc64le because the content of sys/user.h
confuses the clang module importer when it
attempts to import CDispatch.
Signed-off-by: Daniel A. Steffen dsteffen@apple.com>

Remove ObjC support functions not needed on non-ObjC platforms
Signed-off-by: Daniel A. Steffen dsteffen@apple.com>