Speed up cibuildwheel builds

This is done by removing the need to compile or install anything from
boost. For quite a while, boost_system has been header-only (and only
indirectly used, via asio), so references to it are removed. That left
boost_program_options as the only library that spead2 depends on - and
only for command-line tools, not the wheel. So add
`--without-program-options` configure option to allow that dependency to
be skipped, and use it from the Python build.

That allowed the unpacked boost to be "installed" just with a symlink to
the include files rather than a proper installation.

Closes #145.

configure.ac

@@ -38,18 +38,25 @@ CXXFLAGS="$save_CXXFLAGS"
 
 ### Required libraries
 
-SPEAD2_CHECK_LIB([boost/program_options.hpp], [boost_program_options],
-                 [boost::program_options::option_description foo],
-                 [], [AC_MSG_ERROR([boost_program_options is required])])
-SPEAD2_CHECK_LIB([boost/system/system_error.hpp], [boost_system], [boost::system::error_code ec],
-                 [], [AC_MSG_ERROR([boost_system is required])])
-SPEAD2_CHECK_HEADER([boost/asio.hpp], [boost_system,pthread], [boost::asio::io_service io_service],
+SPEAD2_CHECK_HEADER([boost/asio.hpp], [pthread], [boost::asio::io_service io_service],
                     [], [AC_MSG_ERROR([boost_asio is required])])
 SPEAD2_CHECK_HEADER([libdivide.h], [], [libdivide::divider<unsigned long long> div],
                     [], [AC_MSG_ERROR([libdivide is required])])
 
 ### Optional libraries/features
 
+SPEAD2_ARG_WITH(
+    [program_options],
+    [AS_HELP_STRING([--without-program-options], [Do not build utility programs])],
+    [SPEAD2_USE_PROGRAM_OPTIONS],
+    [SPEAD2_CHECK_LIB(
+        [boost/program_options.hpp], [boost_program_options],
+        [boost::program_options::option_description foo],
+        [SPEAD2_USE_PROGRAM_OPTIONS=1],
+        [AC_MSG_ERROR([boost_program_options is required unless --without-program-options is given])]
+    )]
+)
+
 # pkg-config files for libibverbs are quite new, so fall back to searching
 # system paths.
 IBV_CFLAGS=""
@@ -219,7 +226,7 @@ SPEAD2_ARG_WITH(
 
 ### Determine libraries to link against and include paths
 
-LIBS="-lboost_system -lpthread -ldl"
+LIBS="-lpthread -ldl"
 SPEAD2_CFLAGS=""
 AS_IF([test "x$SPEAD2_USE_PCAP" = "x1"], [
     LIBS="$PCAP_LIBS $LIBS"
@@ -266,6 +273,7 @@ AM_CONDITIONAL([SPEAD2_USE_IBV], [test "x$SPEAD2_USE_IBV" = "x1"])
 AM_CONDITIONAL([SPEAD2_USE_CUDA], [test "x$SPEAD2_USE_CUDA" = "x1"])
 AM_CONDITIONAL([SPEAD2_USE_GDRAPI], [test "x$SPEAD2_USE_GDRAPI" = "x1"])
 AM_CONDITIONAL([SPEAD2_USE_CAP], [test "x$SPEAD2_USE_CAP" = "x1"])
+AM_CONDITIONAL([SPEAD2_USE_PROGRAM_OPTIONS], [test "x$SPEAD2_USE_PROGRAM_OPTIONS" = "x1"])
 
 AC_SUBST(SPEAD2_MAJOR, m4_esyscmd([python3 gen/get_version.py major]))
 AC_SUBST(SPEAD2_MINOR, m4_esyscmd([python3 gen/get_version.py minor]))

doc/introduction.rst

@@ -72,19 +72,20 @@ Python install from source
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
 Installing from source requires a modern C++ compiler supporting C++11 (GCC
 4.8+ or Clang 3.5+, although only GCC 11.2 and Clang 14.0 are tested and support
-for older compilers may be dropped) as well as Boost (including compiled
-libraries), libdivide, and the Python development headers. At the moment only
-GNU/Linux and OS X get tested but other POSIX-like systems should work too.
-There are no plans to support Windows.
+for older compilers may be dropped) as well as Boost 1.69+
+(only headers are required), libdivide, and the Python development headers.
+At the moment only GNU/Linux and OS X get tested but other POSIX-like systems
+should work too.  There are no plans to support Windows.
 
 Installation works with standard Python installation methods.
 
 Installing spead2 for C++
 -------------------------
 spead2 requires a modern C++ compiler supporting C++11 (see above for supported
-compilers) as well as Boost (including compiled libraries) and libdivide. At
-the moment only GNU/Linux and OS X get tested but other POSIX-like systems
-should work too.  There are no plans to support Windows.
+compilers) as well as Boost 1.69+ (including the compiled boost_program_options
+library) and libdivide. At the moment only GNU/Linux and OS X get tested but
+other POSIX-like systems should work too. There are no plans to support
+Windows.
 
 The C++ API uses the standard autoconf installation flow i.e.:
 

manylinux/before_all.sh

@@ -23,9 +23,8 @@ unset LDFLAGS
 # Install boost
 wget --progress=dot:mega https://boostorg.jfrog.io/artifactory/main/release/1.81.0/source/boost_1_81_0.tar.bz2 -O /tmp/boost_1_81_0.tar.bz2
 tar -C /tmp -jxf /tmp/boost_1_81_0.tar.bz2
-cd /tmp/boost_1_81_0
-./bootstrap.sh --prefix=/usr --with-libraries=program_options,system
-./b2 cxxflags=-fPIC link=static install
+# Quick-n-dirty approach (much faster than doing the install, which copies thousands of files)
+ln -s /tmp/boost_1_81_0/boost /usr/include/boost
 
 # Install rdma-core
 wget --progress=dot:mega https://github.com/linux-rdma/rdma-core/releases/download/v44.0/rdma-core-44.0.tar.gz -O /tmp/rdma-core-44.0.tar.gz

setup.py

@@ -43,7 +43,9 @@ def initialize_options(self):
 
     def run(self):
         self.mkpath(self.build_temp)
-        subprocess.check_call(os.path.abspath("configure"), cwd=self.build_temp)
+        subprocess.check_call(
+            [os.path.abspath("configure"), "--without-program-options"], cwd=self.build_temp
+        )
         config = configparser.ConfigParser()
         config.read(os.path.join(self.build_temp, "python-build.cfg"))
         for extension in self.extensions:

src/Makefile.am

@@ -20,6 +20,8 @@ bin_PROGRAMS = spead2_recv spead2_send spead2_bench
 check_PROGRAMS = spead2_unittest
 TESTS = spead2_unittest
 
+if SPEAD2_USE_PROGRAM_OPTIONS
+
 if SPEAD2_USE_IBV
 bin_PROGRAMS += mcdump
 mcdump_SOURCES = mcdump.cpp
@@ -35,6 +37,8 @@ spead2_send_LDADD = -lboost_program_options $(LDADD)
 spead2_bench_SOURCES = spead2_bench.cpp spead2_cmdline.cpp
 spead2_bench_LDADD = -lboost_program_options $(LDADD)
 
+endif
+
 if SPEAD2_USE_CAP
 bin_PROGRAMS += spead2_net_raw
 spead2_net_raw_SOURCES = spead2_net_raw.cpp