* Problem: Android build environment variables need clarifications.
Reason: All are spread and initialized throughout the code.
Solution: Declare, initialize and document environment variables on top of build.sh.
Side effect: This participates to documentation.
* Problem: Android APP fails to load ZMQ (ARM64 only)
Seen with physical Android devices running ARM64.
Not seen with ARM, X86 or X86_64.
Any Android APP loading ZMQ fails with:
```
[FATAL] Couldn't load library library zmq from jar. Dependency is required!
```
Unpack zyre-android-2.0.1.jar, find libzmq.so for ARM64 and look for missing
symbols:
```
prompt> unzip zyre-android-2.0.1.jar
prompt> cd lib/arm64-v8a
prompt> nm --undefined-only ./libzmq.so | head
U __aarch64_ldadd4_acq
U __aarch64_ldadd4_acq_rel
U __aarch64_ldadd4_rel
U __aarch64_ldadd4_relax
U __aarch64_ldadd8_acq_rel
U __aarch64_ldadd8_relax
U __aarch64_swp8_acq
U __aarch64_swp8_acq_rel
U __aarch64_swp8_rel
U __aarch64_swp8_relax
prompt>
```
Some more symbols are missing, but those are relevant for this issue.
OK.
These symbols are present in libc++_shared, but not exported ...:
```
prompt> nm libc++_shared.so | grep aarch64
00000000000ee6d0 t __aarch64_cas1_acq_rel
00000000000ee7a0 t __aarch64_cas8_acq_rel
00000000001028f0 b __aarch64_have_lse_atomics
00000000000ee840 t __aarch64_ldadd4_acq_rel
00000000000ee810 t __aarch64_ldadd4_rel
00000000000ee8a0 t __aarch64_ldadd8_acq_rel
00000000000ee870 t __aarch64_ldadd8_relax
00000000000ee7e0 t __aarch64_swp8_acq_rel
prompt>
```
Issue seen also on the WEB, with GCC & CLANG:
- https://bugzilla.redhat.com/show_bug.cgi?id=1830472
- cea175b838
- ...
Solution: Add `-mno-outline-atomics` to CXXFLAGS (FLUTTER fix).
Additionaly, had to introduce NDK_NUMBER.
This variable is calculated in `android_build_helper.sh`.
It represents the numeric form of NDK_VERSION:
```
NDK_VERSION --> NDK_NUMBER
android-ndk-r25 --> 2500
android-ndk-r23c --> 2303
android-ndk-r22 --> 2200
android-ndk-r21e --> 2105
... and so on
```
This will help a few other things (NDK download ?).
Scenario:
```
export CURL=libsodium
cd zyre/builds/android
./ci_build.sh
```
Result:
```
Android (arm) build failed for the following reasons:
Found no library named libzmq.so libsodium.so
/home/stephan/git/zproject-android-testing/libzmq/builds/android/prefix/arm/lib/libzmq.so libsodium.so
```
Caused by PR #4437, where the 2nd commit was to fix Sonatype findings.
Lesson learnt: Not always a good idea to add double quotes around variables ...
Solution: Make VERIFY an array, so that Sonatype won't complain.
Seen when someone has to relaunch `ci_build.sh` manually, for troubleshooting,
or experiment(s), ci_build.sh stops as libraries are already built.
Solution: Clean more temporary/build folders before build.
Note:
To be reported in ZYRE/CZMQ via ZProject.
When called from ZYRE/CZMQ, it's difficult to identify which build script is
being executed
Solution: Modify each `echo` trace to show the project name and Android architecture in progress.
Note:
To be reported in ZYRE/CZMQ via ZProject.
* Problem: Android APP fails to load ZMQ since NDK r25.x
With the help of the dump of ./configure options (former PR):
```
LIBZMQ (arm) - ./configure options to build 'LIBZMQ':
> --quiet
> TOOLCHAIN=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64
> CC=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/armv7a-linux-androideabi21-clang
> CXX=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/armv7a-linux-androideabi21-clang++
> LD=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/ld
> AS=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-as
> AR=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-ar
> RANLIB=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-ranlib
> STRIP=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-strip
> CFLAGS= -D_GNU_SOURCE -D_REENTRANT -D_THREAD_SAFE
> CPPFLAGS= -I/home/stephan/git/zproject-android-testing/libzmq/builds/android/prefix/arm/include
> CXXFLAGS=
> LDFLAGS=-L/home/stephan/git/zproject-android-testing/libzmq/builds/android/prefix/arm/lib -L/tmp/android-ndk-r25/sour\
ces/cxx-stl/llvm-libc++/libs/armeabi-v7a
> LIBS=-lc -ldl -lm -llog -lc++_shared
> PKG_CONFIG_LIBDIR=/tmp/android-ndk-r25/prebuilt/linux-x86_64/lib/pkgconfig
> PKG_CONFIG_PATH=/home/stephan/git/zproject-android-testing/libzmq/builds/android/prefix/arm/lib/pkgconfig
> PKG_CONFIG_SYSROOT_DIR=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/sysroot
> PKG_CONFIG_DIR=
> --with-sysroot=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/sysroot
> --host=arm-linux-androideabi
> --prefix=/home/stephan/git/zproject-android-testing/libzmq/builds/android/prefix/arm
> --disable-curve
> --without-docs
```
We can observe that LDFLAGS has invalid `-L<path_to_libc++_shared.so>`:
```
-L/tmp/android-ndk-r25/sources/cxx-stl/llvm-libc++/libs/armeabi-v7a
```
This path is no more valid, since NDK r25, where one should use LLVM path.
Ok, once this is fixed, ./configure requires also the path to libc.so.
I don't understand why libc.so is now required, actually, but without this, ./configure fails
to build its conftest.
Solution: Fix invalid LDFLAGS.
Notes:
- To be reported to CZMQ/ZYRE via ZPROJECT.
- Tested successfully with Android Emulator (x86 & x86_64).
- Still need some more work, as execution still fails with physical devices (observed on arm64).
- Introduced `ANDROID_STL`, `ANDROID_STL_ROOT` & `ANDROID_LIBC_ROOT`. All are initialized in `android_build_helper.sh`.
- New mechanism **MUST** be compatible with former NDK versions.
Proposal is to dump ./configure options to have an output like below:
```
LIBZMQ (x86_64) - ./configure options to build 'LIBZMQ':
> --quiet
> TOOLCHAIN=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64
> CC=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/x86_64-linux-android21-clang
> CXX=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/x86_64-linux-android21-clang++
> LD=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/ld
> AS=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-as
> AR=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-ar
> RANLIB=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-ranlib
> STRIP=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-strip
> CFLAGS= -D_GNU_SOURCE -D_REENTRANT -D_THREAD_SAFE
> CPPFLAGS= -I/builds/CrisalidBox/zproject-android-testing/libzmq/builds/android/prefix/x86_64/include
> CXXFLAGS=
> LDFLAGS=-L/builds/CrisalidBox/zproject-android-testing/libzmq/builds/android/prefix/x86_64/lib -L/tmp/android-ndk-r25/sources/cxx-stl/llvm-libc++/libs/x86_64
> LIBS=-lc -ldl -lm -llog -lc++_shared
> PKG_CONFIG_LIBDIR=/tmp/android-ndk-r25/prebuilt/linux-x86_64/lib/pkgconfig
> PKG_CONFIG_PATH=/builds/CrisalidBox/zproject-android-testing/libzmq/builds/android/prefix/x86_64/lib/pkgconfig
> PKG_CONFIG_SYSROOT_DIR=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/sysroot
> PKG_CONFIG_DIR=
> --with-sysroot=/tmp/android-ndk-r25/toolchains/llvm/prebuilt/linux-x86_64/sysroot
> --host=x86_64-linux-android
> --prefix=/builds/CrisalidBox/zproject-android-testing/libzmq/builds/android/prefix/x86_64
> --disable-curve
> --without-docs
```
Note:
This mechanism is currently in use to identify/fix a bug in a recent PR for NDK update.
This mechanism is added before every call of `./configure`.
To be reported to CZMQ/ZYRE (via ZPROJECT).
Solution: Use `set -e`
Note:
To be reported in ZPROJECT, when generating the same for CZMQ & ZYRE.
Note:
`make clean` may fail when Makefile is not yet generated
(case of 1st call of build.sh after git clone).
Additionnaly, cleaned the dependency folder
(report of ZPROJECT generated scripts).
Seen in the code:
```
function android_build_verify_so {
...
for dep_soname do
if [[ $elfoutput != *"library: [${dep_soname}]"* ]]; then
ANDROID_BUILD_FAIL+=("Library ${soname} was expected to be linked to library with soname:")
ANDROID_BUILD_FAIL+=(" ${dep_soname}")
fi
done
```
The `for xxx` syntax is wrong, most probably a typo somewhere.
Solution: Fix & complete the `for xxx` loop.
Tested with & without LIBSODIUM (only available dependent library for LIBZMQ).
Note: The same has to be done in ZPROJECT, for CZMQ & ZYRE.
Solution: Replace incorrect underline pattern in zmq_udp.txt that
makes part of the text show up as pre-formatted code block with
regular underline pattern.
* Problem: In rare cases, afunix.h doesn't contain a definition for struct sockaddr_un
According to https://github.com/microsoft/vcpkg/issues/21623,
struct sockaddr_un might be unavailable on some machines even afunix.h exists.
For example, on some machines, the content of afunix.h looks like this:
typedef struct _SOCKADDR_UN
{
ADDRESS_FAMILY Family;
wchar_t Path[63];
} SOCKADDR_UN, *PSOCKADDR_UN;
but on other machines, it may looks like this:
#define UNIX_PATH_MAX 108
typedef struct sockaddr_un
{
ADDRESS_FAMILY sun_family;
char sun_path[UNIX_PATH_MAX];
} SOCKADDR_UN, *PSOCKADDR_UN;
Fixes#3949
References:
- [Enable Unix-domain sockets support on Windows](8f3ec75de4)
- [AF_UNIX equivalent for Windows](https://stackoverflow.com/questions/9029174/af-unix-equivalent-for-windows)
- https://devblogs.microsoft.com/commandline/af_unix-comes-to-windows/
Solution: When compiling with gcc 7 and newer, the program produced by
AC_CHECK_FUNCS(fork) produces a warning, which results in configure
incorrectly disabling fork support. Fix the issue by using an
AC_COMPILE_IFELSE which correctly detects fork availability.
Tested by running configure and make check on a system with gcc 7
installed, and verifying that HAVE_FORK was defined correctly.
See issue #3313.
