Use Meson's pkg-config generator

The .pc file is now generated using Meson generator, so there's no need
anymore to store a .pc.in file in the project root and then configure it
manually. All dependencies and libraries are automatically set based on
what the build target actually uses, so there's no need to manually
track all the required libs and flags. As a result, code is much cleaner

CMakeModules/CheckAtomic.cmake

-# Source: https://github.com/llvm-mirror/llvm/blob/master/cmake/modules/CheckAtomic.cmake
-# atomic builtins are required for threading support.
-
-INCLUDE(CheckCXXSourceCompiles)
-INCLUDE(CheckLibraryExists)
-
-# Sometimes linking against libatomic is required for atomic ops, if
-# the platform doesn't support lock-free atomics.
-
-function(check_working_cxx_atomics varname)
-  set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
-  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++11")
-  CHECK_CXX_SOURCE_COMPILES("
-#include <atomic>
-std::atomic<int> x;
-int main() {
-  return x;
-}
-" ${varname})
-  set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
-endfunction(check_working_cxx_atomics)
-
-function(check_working_cxx_atomics64 varname)
-  set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
-  set(CMAKE_REQUIRED_FLAGS "-std=c++11 ${CMAKE_REQUIRED_FLAGS}")
-  CHECK_CXX_SOURCE_COMPILES("
-#include <atomic>
-#include <cstdint>
-std::atomic<uint64_t> x (0);
-int main() {
-  uint64_t i = x.load(std::memory_order_relaxed);
-  return 0;
-}
-" ${varname})
-  set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
-endfunction(check_working_cxx_atomics64)
-
-
-# This isn't necessary on MSVC, so avoid command-line switch annoyance
-# by only running on GCC-like hosts.
-if (CMAKE_CXX_COMPILER_ID MATCHES "Clang|GNU")
-  # First check if atomics work without the library.
-  check_working_cxx_atomics(HAVE_CXX_ATOMICS_WITHOUT_LIB)
-  # If not, check if the library exists, and atomics work with it.
-  if(NOT HAVE_CXX_ATOMICS_WITHOUT_LIB)
-    check_library_exists(atomic __atomic_fetch_add_4 "" HAVE_LIBATOMIC)
-    if( HAVE_LIBATOMIC )
-      list(APPEND CMAKE_REQUIRED_LIBRARIES "atomic")
-      check_working_cxx_atomics(HAVE_CXX_ATOMICS_WITH_LIB)
-      if (NOT HAVE_CXX_ATOMICS_WITH_LIB)
-	message(FATAL_ERROR "Host compiler must support std::atomic!")
-      endif()
-    else()
-      message(FATAL_ERROR "Host compiler appears to require libatomic, but cannot find it.")
-    endif()
-  endif()
-endif()
-
-# Check for 64 bit atomic operations.
-if(MSVC)
-  set(HAVE_CXX_ATOMICS64_WITHOUT_LIB True)
-else()
-  check_working_cxx_atomics64(HAVE_CXX_ATOMICS64_WITHOUT_LIB)
-endif()
-
-# If not, check if the library exists, and atomics work with it.
-if(NOT HAVE_CXX_ATOMICS64_WITHOUT_LIB)
-  check_library_exists(atomic __atomic_load_8 "" HAVE_CXX_LIBATOMICS64)
-  if(HAVE_CXX_LIBATOMICS64)
-    list(APPEND CMAKE_REQUIRED_LIBRARIES "atomic")
-    check_working_cxx_atomics64(HAVE_CXX_ATOMICS64_WITH_LIB)
-    if (NOT HAVE_CXX_ATOMICS64_WITH_LIB)
-      message(FATAL_ERROR "Host compiler must support 64-bit std::atomic!")
-    endif()
-  else()
-    message(FATAL_ERROR "Host compiler appears to require libatomic for 64-bit operations, but cannot find it.")
-  endif()
-endif()

include/pistache/meson.build

+prefix = get_option('prefix')
+
 configure_file(input: 'version.h.in', output: 'version.h', configuration: version_data_conf, install: get_option('PISTACHE_INSTALL'), install_dir: prefix/get_option('includedir')/'pistache')
 
 install_headers([

libpistache.pc.in

-prefix=@prefix@
-exec_prefix=@exec_prefix@
-libdir=@libdir@
-includedir=@includedir@
-
-Name: libpistache
-URL: http://pistache.io/
-Description: An elegant C++ REST framework.
-Version: @version@
-Libs: -L'${libdir}/' @libs@
-Libs.private: @libs_private@
-Cflags: -I'${includedir}/'

meson.build

@@ -15,9 +15,6 @@ project(
 
 compiler = meson.get_compiler('cpp')
 compiler_id = compiler.get_id()
-prefix = get_option('prefix')
-pc_lib = '-lpistache'
-pc_libs_private = ['-pthread']
 
 # Wrapping arguments inside a call to get_supported_arguments so that only supported arguments get applied
 # No need for -Wall -Wextra -Wpedantic, since warning_level is 3
@@ -28,49 +25,10 @@ if get_option('b_coverage')
 	add_project_arguments(compiler.get_supported_arguments(['-fstack-protector-all', '--param=ssp-buffer-size=4']), language: 'cpp')
 endif
 
-##### BEGIN CheckAtomic.cmake
-is_libatomic_needed = false
-
-cxx_atomics_check_code = '''
-#include <atomic>
-std::atomic<int> x;
-int main(){return x;}
-'''
-has_working_cxx_atomics = compiler.compiles(cxx_atomics_check_code, name: 'std::atomic')
-if (compiler_id.contains('clang') or compiler_id.contains('gcc')) and not has_working_cxx_atomics
-	assert(compiler.has_function('__atomic_fetch_add_4', args: '-latomic'), 'Host compiler appears to require libatomic, but cannot find it.')
-	has_working_cxx_atomics = compiler.compiles(cxx_atomics_check_code, args: '-latomic', name: 'std::atomic with libatomic')
-	assert(has_working_cxx_atomics, 'Host compiler must support std::atomic!')
-	is_libatomic_needed = true
-endif
-
-cxx_atomics64_check_code = '''
-#include <atomic>
-#include <cstdint>
-std::atomic<uint64_t> x(0);
-int main() {
-uint64_t i = x.load(std::memory_order_relaxed);
-return 0;
-}
-'''
-has_working_cxx_atomics64 = compiler.compiles(cxx_atomics64_check_code, name: 'std::atomic<uint64_t>')
-if not has_working_cxx_atomics64
-	assert(compiler.has_function('__atomic_load_8', args: '-latomic'), 'Host compiler appears to require libatomic for 64-bit operations, but cannot find it.')
-	has_working_cxx_atomics = compiler.compiles(cxx_atomics_check_code, args: '-latomic', name: 'std::atomic<uint64_t> with libatomic')
-	assert(has_working_cxx_atomics, 'Host compiler must support 64-bit std::atomic')
-	is_libatomic_needed = true
-endif
-##### END CheckAtomic.cmake
-
-if is_libatomic_needed
-	pc_libs_private += '-latomic'
-endif
-
 deps_libpistache = [dependency('threads'), dependency('RapidJSON', fallback: ['rapidjson', 'rapidjson_dep'])]
 
 if get_option('PISTACHE_USE_SSL')
 	deps_libpistache += dependency('openssl')
-	pc_libs_private += ['-lssl', '-lcrypto']
 endif
 
 version_data_raw = ''
@@ -94,16 +52,6 @@ endforeach
 pistache_version_str = '.'.join([version_data_conf.get_unquoted('VERSION_MAJOR'), version_data_conf.get_unquoted('VERSION_MINOR'), version_data_conf.get_unquoted('VERSION_PATCH')])
 pistache_soversion_str = '.'.join([version_data_conf.get_unquoted('SONAME_VERSION_MAJOR'), version_data_conf.get_unquoted('SONAME_VERSION_MINOR')])
 
-configure_file(input: 'libpistache.pc.in', output: 'libpistache.pc', install: get_option('PISTACHE_INSTALL'), install_dir: get_option('libdir')/'pkgconfig', configuration: {
-	'prefix': prefix,
-	'exec_prefix': prefix/get_option('bindir'),
-	'libdir': prefix/get_option('libdir'),
-	'libs': pc_lib,
-	'libs_private': ' '.join(pc_libs_private),
-	'includedir': prefix/get_option('includedir'),
-	'version': pistache_version_str+'-git'+version_data_conf.get_unquoted('VERSION_GIT_DATE')
-})
-
 incl_pistache = include_directories('include')
 
 subdir('include')

src/meson.build

@@ -47,3 +47,13 @@ pistache_dep = declare_dependency(link_with: libpistache, include_directories: i
 if meson.version().version_compare('>=0.54.0')
 	meson.override_dependency('pistache', pistache_dep)
 endif
+
+pkg = import('pkgconfig')
+pkg.generate(
+   libpistache,
+   name: 'Pistache',
+   description: 'An elegant C++ REST framework.',
+   url: 'http://pistache.io',
+   version: pistache_version_str+'-git'+version_data_conf.get_unquoted('VERSION_GIT_DATE'),
+   filebase: 'libpistache'
+)