As acfac7a#r124469888 mentioned, LibeventConfig.cmake is looking for MBedTLS package, even if libevent is not configured to use MBedTLS.
This PR makes MbedTLS and OpenSSL dependencies configurable.
Fixes: #1543
Previous settings caused install outside CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES
to use install_name "lib/" in place of the expected (and useful) "@rpath/".
After rebasing I broke the initial intention of this patch, so it simply
should be reverted.
This reverts commit 81c6b8823c1b58d7837e827bb1098aa5f9e5956b.
The generated configurations for both CMake and pkg-config included
absolute paths to dependencies (OpenSSL, MbedTLS). This is contrary
to the general CMake advise to create relocatable packages [1].
Additionally, when building both mbedtls and libevent via CMake's
FetchContent in the same project, loading the project would fail with
INTERFACE_INCLUDE_DIRECTORIES property contains path:
"/home/user/project/cmake-build/_deps/mbedtls-build/include"
which is prefixed in the source directory.
The required changes include:
- Adding the outer includes only to the BUILD_INTERFACE solves the
makes the CMake paths relocatable and thus solves the FetchContent
problem.
- Updates to libevent_*.pc.in fixes the relocatable issues for
pkg-config and properly declares currently missing dependencies.
- Using components for linking to OpenSSL (requiring CMake 3.4)
and MbedTLS. The new MbedTLS target names now match the component
names of the MbedTLS' CMake project.
- Use the Threads CMake library reference instead of a direct
reference to support both built-in pthread and -lpthread.
v2 (azat): get back CMAKE_REQUIRED_LIBRARIES
[1] https://cmake.org/cmake/help/v3.25/manual/cmake-packages.7.html#creating-relocatable-packages
As described in #1404, the explicit use of CMAKE_INSTALL_PREFIX conflicts with using command-line --prefix.
This simply removes all explicit use of CMAKE_INSTALL_PREFIX.
Otherwise this path will be duplicated:
$ cmake -DCMAKE_BUILD_TYPE=debug -DCMAKE_EXPORT_COMPILE_COMMANDS=ON -DCMAKE_INSTALL_PREFIX=inst ..
$ DESTDIR=inst ninja install
...
-- Installing: inst/src/le/libevent/.cmake-debug/inst/include/event2/util.h
-- Installing: inst/src/le/libevent/.cmake-debug/inst/include/event2/ws.h
...
Fixes: #1404
Co-authored-by: Jeremy Murphy <jeremymu@blackmagicdesign.com>
CMake config files don't need any logic to detect the location of
installed headers or DSOs, because these locations are already
determined at project configuration time. They also don't need
to distinguish between build and install trees, because that is
already handled by the generated `LibeventTargets-*.cmake` files.
mingw has upgraded to Mbed-TLS 3.1.0, so all the mingw tests that need
Mbed-TLS currently don't work.
v2: add missing mbedtls/version.h into test/regress_mbedtls.c
v3: suppress #warning "Including compat-2.x.h is deprecated" for mbedtls/compat-2.x.h
When add_event_library macro was called without the INNER_LIBRARIES parameter, it reused the
value set by a previous call, since the INNER_LIBRARIES variable was not reset.
As pointed by @kloczek:
"With only two characters it would be harder to guess under what kind of name are libevent lvl 3 man pages.
Longer name with bash/fix/zsh tab competition should not be a problem :)"
Refs: #1099
This will:
- avoid overlapping (since there is util.h.3 page)
- group everything under some prefix (man le_<TAB><TAB> will show everything)
Fixes: #1099
Checking functions with `CheckFunctionExists` may
get wrong results, we should replace it with
`CheckSymbolExists`, which is recommended by the cmake
official documentation.
Before using `CheckSymbolExists`, we use
`CheckIncludeFiles` to check header files and save the
available header files in a variable that guarantees
`CheckSymbolExists` and `CheckTypeSize` to work correctly.
This approach is modeled after the cmake scripts of `curl`.
The following functions or files were not found before
modification, they can now be found:
- msys2 + mingw-8.1.0 on Windows10 or mingw-7.3.0 on Ubuntu-18.04
timerclear
timercmp
timerisset
- windows10
getaddrinfo
getnameinfo
getprotobynumber
getservbyname
putenv
strtoll
timerclear
timercmp
timerisset
- ubuntu-18.04
sys/sysctl.h
timeradd
timerclear
timercmp
timerisset
- MacOS 10.13
sys/random.h
timeradd
timerclear
timercmp
timerisset
The current cmake/LibeventConfig.cmake.in has a few problems and I'm not
sure how cleanly developed it is. It seems rater complex for the little
things I would assume it needs to do.
I found two problems that are fixed in this PR:
- If the downstream user does not explicitly set LIBEVENT_STATIC_LINK
before calling find_package(libevent) then they will not be able to
detect the static library, even if its the only one that exists. Since
this may be rather strict, I've changed the behavior so that
LIBEVENT_STATIC_LINK can be set to ON or OFF, but if unset, it defaults
to whatever configuration libevent was built as.
- The other problem is a bug. The package configuration needs to unset
CMAKE_FIND_LIBRARY_SUFFIXES after use, otherwise all packages that are
detected after libevent will be "infected" by this setting. This was a
significant problem for us, and is very hard to detect in downstream
project, because the order of dependencies will lead to different search
results.
Using `CheckFunctionExists` on Windows to check `getaddrinfo`
will get `not found`, but it actually exists. Using `CheckSymbolExists`
with headers will get correct results. Other functions such as
`getnameinfo`,`inet_ntop`,etc. have the same issue.
`CheckFunctionExistsEx` is copied from the cmake modules before
3.1.2, which is the minimum required version of libevent.
The internal module `CheckFunctionExists`of cmake can completely
replace it.
- Documentation for `bufferevent_compat.h` and `rpc.h` is not generated
since the `@file` command is missing. It can be fixed by adding
`@file` in file comment block.
- The briefs of buffer.h,bufferevent.h and some other files are missing.
Adding `@brief` command can fix it.
- The parameters in the function declaration are different from the
parameters following the `@param` command.We should change them to the
same.
- Documentation of `watch.h` is not generated since `watch.h` has not
been added to the Doxyfile `INPUT` tag.
- Add link to the watch.h in event.h
$ cmake -DEVENT__LIBRARY_TYPE=static ..
...
CMake Error:
Error evaluating generator expression:
$<TARGET_FILE_DIR:event_core_shared>
No target "event_core_shared"
Fixes: #853
Fixes: 669a53f3 ("cmake: set library names to be the same as with autotools")
libtool has VERSION_INFO [1], cmake has SOVERSION/VERSION instead
(although it has different format). Also libtool has RELEASE [2] while
cmake do not have analog yet [3], hence manual symlinks should be
created.
[1]: https://www.gnu.org/software/libtool/manual/html_node/Libtool-versioning.html
[2]: https://www.gnu.org/software/libtool/manual/html_node/Release-numbers.html
[3]: https://gitlab.kitware.com/cmake/cmake/issues/17652
Plus osx has compatibility_version/current_version dylib properties and
cmake do not have separate properties for them [4], hence manual LINK_FLAGS.
And also there INSTALL_NAME_DIR property which should be adjusted too.
[4]: https://public.kitware.com/Bug/view.php?id=4383
So after all changes, here is an example before/after for osx and linux:
# osx
# autotools
.libs/libevent_pthreads-2.2.1.dylib
.libs/libevent_pthreads.dylib -> libevent_pthreads-2.2.1.dylib
/usr/local/lib/libevent_pthreads-2.2.1.dylib (compatibility version 2.0.0, current version 2.0.0)
# cmake
# before patch
lib/libevent_pthreads.2.2.0.dylib
lib/libevent_pthreads.dylib -> libevent_pthreads.2.2.0.dylib
@rpath/libevent_pthreads.2.2.0.dylib (compatibility version 2.2.0, current version 0.0.0)
# after patch
lib/libevent_pthreads-2.2.1.dylib
lib/libevent_pthreads.dylib -> libevent_pthreads-2.2.1.dylib
/vagrant/.cmake/inst/lib/libevent_pthreads-2.2.1.dylib (compatibility version 2.0.0, current version 2.0.0)
# linux
# autotools
.libs/libevent_pthreads-2.2.so.1 -> libevent_pthreads-2.2.so.1.0.0
.libs/libevent_pthreads-2.2.so.1.0.0
.libs/libevent_pthreads.so -> libevent_pthreads-2.2.so.1.0.0
# cmake
# before patch
lib/libevent_pthreads.so -> libevent_pthreads.so.2.2.0
lib/libevent_pthreads.so.2.2.0
# after patch
lib/libevent_pthreads-2.2.so -> libevent_pthreads-2.2.so.1
lib/libevent_pthreads-2.2.so.1 -> libevent_pthreads-2.2.so.1.0.0
lib/libevent_pthreads-2.2.so.1.0.0
lib/libevent_pthreads.so -> libevent_pthreads-2.2.so.1.0.0
Closes: #838 (cherry-picked)
Closes: #760
Long time ago in [1] cmake build was forced to compile both libraries
(SHARED and STATIC), since this is how our autotools build works.
[1]: 7182c2f561570cd9ceb704623ebe9ae3608c7b43 ("cmake: build SHARED and STATIC libraries (like autoconf does)")
And there is no way to configure this (and indeed you need to do this
for MSVC for example), so let's introduce option for this --
EVENT__LIBRARY_TYPE.
Plus now we have INTERFACE libraries, that we can use internally in
libevent's cmake rules to avoid strict to _shared/_static variant of the
libraries to link with samples/tests (we prefer SHARED over STATIC for
linking).
Also bump minimal cmake required version to 3.1 by the following
reasons:
- 3.1 is required for RPATH configuration under APPLE
- 3.0 is required for add_library(INTERFACE) (did not found it in 2.8.x
documentation)
- remove extra conditions
(anyway 3.1 was release 4 years ago, so I guess that most of the systems
will have it)
For example under mingw64 it could not detect that strtok_r() exists,
because it checks with:
void *p = func_name;
And for this you need the function to be defined, so just sync our
CheckFunctionExistsEx.c with CheckFunctionExists.c from cmake (and later
we should drop them out) since it does correct things to detech
functions existence.
Also for WIN32 there is -FIwinsock2.h -FIws2tcpip.h, and I guess that is
not works for mingw gcc (since -F in gcc is framework, and in windows
-FI is like -include in gcc). But looks like we do not need them
already (due to fixed CheckFunctionExistsEx()).
Refs: #605
by default, the max buffer size is 16K and histeresis is at 50%, so
a bigger read is needed to unlock writes than you would expect from
other BSD (512 bytes)
this doesn't introduce any regression on FreeBSD 11.1, OpenBSD 6.1, NetBSD 7.1,
macOS 10.12.6 and of course DragonFlyBSD 4.8.1, and most of them show
a max pipe size of 64K, so the read call should drain them all regardless
of how conservative they are on the free pipe space they will require
(usually 512 bytes) before kevent reports the fd as ready for write.
I couldn't find a reference to which bug this code was trying to look for
and it seems to be there from the beginning of git history so it might be
no longer relevant.
Issue: #548
On centos with cmake 2.8.12.2:
CMake Error at cmake/AddEventLibrary.cmake:92 (export):
export called with target "event_extra_shared" which requires target
"event_core_shared" that is not in the export list.
If the required target is not easy to reference in this call, consider
using the APPEND option with multiple separate calls.
But on newer cmake I guess everything is ok.
Fixes: 7182c2f561570cd9ceb704623ebe9ae3608c7b43 ("cmake: build SHARED
and STATIC libraries (like autoconf does)")
Remove next vars, since I don't think that somebody want to change it:
- bin
- lib
- include
And fix exports problem:
CMake Error: INSTALL(EXPORT "LibeventTargets") given absolute DESTINATION "/usr/lib/cmake/libevent" but the export references an installation of target "event_core_static" which has relative DESTINATION "lib".
Since they are useful for debugging, and if autotools build them then
cmamke has to do this too, to make migration more simple.
And now:
- tests: uses shared libraries (since this is upstreams one)
- other binaries: uses static libraries
This removes next private config:
- EVENT__NEED_DLLIMPORT
This will remove openssl requirement if you don't use it (i.e. if you
not link with openssl_pthreads).
Plus it fixes some linking dependencies:
- libm required only for test-ratelim
And fix some coding style alignment issues.
Refs: #246
