Merge pull request #4173 from mapnik/c++17

Support for C++17 builds

SConstruct

@@ -56,8 +56,9 @@ ICU_LIBS_DEFAULT='/usr/'
 
 DEFAULT_CC = "cc"
 DEFAULT_CXX = "c++"
-DEFAULT_CXX14_CXXFLAGS = " -std=c++14 -DU_USING_ICU_NAMESPACE=0"
+DEFAULT_CXX_STD = "14"
-DEFAULT_CXX14_LINKFLAGS = ""
+DEFAULT_CXX_CXXFLAGS = " -DU_USING_ICU_NAMESPACE=0"
+DEFAULT_CXX_LINKFLAGS = ""
 if sys.platform == 'darwin':
     # homebrew default
     ICU_INCLUDES_DEFAULT='/usr/local/opt/icu4c/include/'
@@ -355,6 +356,7 @@ opts = Variables()
 opts.AddVariables(
     # Compiler options
     ('CXX', 'The C++ compiler to use to compile mapnik', DEFAULT_CXX),
+    ('CXX_STD', 'The C++ compiler standard (string).', DEFAULT_CXX_STD),
     ('CC', 'The C compiler used for configure checks of C libs.', DEFAULT_CC),
     ('CUSTOM_CXXFLAGS', 'Custom C++ flags, e.g. -I<include dir> if you have headers in a nonstandard directory <include dir>', ''),
     ('CUSTOM_DEFINES', 'Custom Compiler DEFINES, e.g. -DENABLE_THIS', ''),
@@ -487,6 +489,7 @@ opts.AddVariables(
 pickle_store = [# Scons internal variables
         'CC', # compiler user to check if c deps compile during configure
         'CXX', # C++ compiler to compile mapnik
+        'CXX_STD', # C++ standard e.g 17 (as in -std=c++17)
         'CFLAGS',
         'CPPDEFINES',
         'CPPFLAGS', # c preprocessor flags
@@ -1227,28 +1230,29 @@ int main()
     context.Result(ret)
     return ret
 
-def supports_cxx14(context,silent=False):
+__cplusplus = {'14':'201402L', '17':'201703L'}
+
+def supports_cxx_std (context, silent=False):
+    cplusplus_string = __cplusplus[env['CXX_STD']]
     if not silent:
-        context.Message('Checking if compiler (%s) supports -std=c++14 flag... ' % context.env.get('CXX','CXX'))
+        context.Message('Checking if compiler (%s) supports -std=c++%s flag... ' % (context.env.get('CXX','CXX'), env['CXX_STD']))
     ret, out = context.TryRun("""
 
 int main()
 {
-#if __cplusplus >= 201402L
+#if __cplusplus >= %s
     return 0;
 #else
     return -1;
 #endif
 }
 
-""", '.cpp')
+""" % cplusplus_string ,'.cpp')
     if silent:
         context.did_show_result=1
     context.Result(ret)
     return ret
 
-
-
 conf_tests = { 'prioritize_paths'      : prioritize_paths,
                'CheckPKGConfig'        : CheckPKGConfig,
                'CheckPKG'              : CheckPKG,
@@ -1270,7 +1274,7 @@ conf_tests = { 'prioritize_paths'      : prioritize_paths,
                'harfbuzz_with_freetype_support': harfbuzz_with_freetype_support,
                'boost_regex_has_icu'   : boost_regex_has_icu,
                'sqlite_has_rtree'      : sqlite_has_rtree,
-               'supports_cxx14'        : supports_cxx14,
+               'supports_cxx_std'      : supports_cxx_std,
                'CheckBoostScopedEnum'  : CheckBoostScopedEnum,
                }
 
@@ -1414,13 +1418,13 @@ if not preconfigured:
 
     # set any custom cxxflags and ldflags to come first
     if sys.platform == 'darwin' and not env['HOST']:
-        DEFAULT_CXX14_CXXFLAGS += ' -stdlib=libc++'
+        DEFAULT_CXX_CXXFLAGS += ' -stdlib=libc++'
-        DEFAULT_CXX14_LINKFLAGS = ' -stdlib=libc++'
+        DEFAULT_CXX_LINKFLAGS = ' -stdlib=libc++'
     env.Append(CPPDEFINES = env['CUSTOM_DEFINES'])
-    env.Append(CXXFLAGS = DEFAULT_CXX14_CXXFLAGS)
+    env.Append(CXXFLAGS = "-std=c++%s %s" % (env['CXX_STD'], DEFAULT_CXX_CXXFLAGS))
     env.Append(CXXFLAGS = env['CUSTOM_CXXFLAGS'])
     env.Append(CFLAGS = env['CUSTOM_CFLAGS'])
-    env.Append(LINKFLAGS = DEFAULT_CXX14_LINKFLAGS)
+    env.Append(LINKFLAGS = DEFAULT_CXX_LINKFLAGS)
 
     custom_ldflags = env.ParseFlags(env['CUSTOM_LDFLAGS'])
     env.Append(LINKFLAGS = custom_ldflags.pop('LINKFLAGS'),
@@ -1600,9 +1604,10 @@ if not preconfigured:
     if env['PRIORITIZE_LINKING']:
         conf.prioritize_paths(silent=True)
 
-    # test for C++14 support, which is required
+    # test for CXX_STD support, which is required
-    if not env['HOST'] and not conf.supports_cxx14():
+    if not env['HOST'] and not conf.supports_cxx_std():
-        color_print(1,"C++ compiler does not support C++14 standard (-std=c++14), which is required. Please upgrade your compiler")
+        color_print(1,"C++ compiler does not support C++%s standard (-std=c++%s), which is required."
+                      " Please upgrade your compiler" % (env['CXX_STD'], env['CXX_STD']))
         Exit(1)
 
     if not env['HOST']:

src/image_util.cpp

@@ -53,6 +53,10 @@
 #include <sstream>
 #include <algorithm>
 
+#if __cplusplus >= 201703L
+#include <execution>
+#endif
+
 namespace mapnik
 {
 
@@ -420,19 +424,18 @@ struct is_solid_visitor
     {
         return true;
     }
-
     template <typename T>
-    bool operator() (T const & data) const
+    bool operator() (image_view<T> const& view) const
     {
         using pixel_type = typename T::pixel_type;
-        if (data.width() > 0 && data.height() > 0)
+        if (view.width() > 0 && view.height() > 0)
         {
-            pixel_type const* first_row = data.get_row(0);
+            pixel_type const* first_row = view.get_row(0);
             pixel_type const first_pixel = first_row[0];
-            for (std::size_t y = 0; y < data.height(); ++y)
+            for (std::size_t y = 0; y < view.height(); ++y)
             {
-                pixel_type const * row = data.get_row(y);
+                pixel_type const * row = view.get_row(y);
-                for (std::size_t x = 0; x < data.width(); ++x)
+                for (std::size_t x = 0; x < view.width(); ++x)
                 {
                     if (first_pixel != row[x])
                     {
@@ -443,6 +446,24 @@ struct is_solid_visitor
         }
         return true;
     }
+
+    template <typename T>
+    bool operator() (T const& image) const
+    {
+        using pixel_type = typename T::pixel_type;
+        if (image.size() > 0)
+        {
+            pixel_type const first_p = *image.begin();
+            auto itr = std::find_if(/*std::execution::par_unseq,*/ // still missing on ubuntu with
+                                                                   // clang++10/libc++ (!)
+                                    image.begin(), image.end(),
+                                    [first_p](pixel_type const p) {
+                                        return first_p != p;
+                                    });
+            return (itr == image.end());
+        }
+        return true;
+    }
 };
 
 } // end detail ns

test/unit/datasource/geojson.cpp

@@ -67,6 +67,16 @@ std::pair<mapnik::datasource_ptr,mapnik::feature_ptr> fetch_first_feature(std::s
     return std::make_pair(ds,feature);
 }
 
+
+void iterate_over_features(mapnik::featureset_ptr features)
+{
+    auto feature = features->next();
+    while (feature != nullptr)
+    {
+        feature = features->next();
+    }
+}
+
 }
 
 TEST_CASE("geojson") {
@@ -673,12 +683,7 @@ TEST_CASE("geojson") {
                 auto fields = ds->get_descriptor().get_descriptors();
                 mapnik::query query(ds->envelope());
                 auto features = ds->features(query);
-                REQUIRE_THROWS(
+                REQUIRE_THROWS(iterate_over_features(features));
-                    auto feature = features->next();
-                    while (feature != nullptr)
-                    {
-                        feature = features->next();
-                    });
             }
 
             // cleanup

test/unit/imaging/image_filter.cpp

@@ -19,16 +19,14 @@ SECTION("test bad filter input") {
     mapnik::fill(im,mapnik::color("blue"));
     mapnik::set_pixel(im, 1, 1, mapnik::color("red"));
 
-    REQUIRE_THROWS( mapnik::filter::filter_image(im, "foo,asdfasdf()"); );
+    REQUIRE_THROWS( mapnik::filter::filter_image(im, "foo,asdfasdf()"));
-    REQUIRE_THROWS( mapnik::filter::filter_image(im, "colorize-alpha("); );
+    REQUIRE_THROWS( mapnik::filter::filter_image(im, "colorize-alpha("));
-    REQUIRE_THROWS( mapnik::filter::filter_image(im, "color-to-alpha(blue"); );
+    REQUIRE_THROWS( mapnik::filter::filter_image(im, "color-to-alpha(blue"));
-    REQUIRE_THROWS( mapnik::filter::filter_image(im, "color-to-alpha(,blue)"); );
+    REQUIRE_THROWS( mapnik::filter::filter_image(im, "color-to-alpha(,blue)"));
-    REQUIRE_THROWS( mapnik::filter::filter_image(im, "colorize-alpha()"); );
+    REQUIRE_THROWS( mapnik::filter::filter_image(im, "colorize-alpha()"));
 
-    REQUIRE_THROWS(
     mapnik::image_rgba8 const& im2 = im;
-        mapnik::image_rgba8 new_im = mapnik::filter::filter_image(im2, "foo");
+    REQUIRE_THROWS(mapnik::filter::filter_image(im2, "foo"));
-    );
 
     CHECK(im(0,0) == 0xffff0000);
     CHECK(im(0,1) == 0xffff0000);
@@ -158,7 +156,7 @@ SECTION("test scale-hsla 2") {
 
     // Should not throw on values out of [0, 1]
     // https://github.com/mapnik/mapnik/issues/3052
-    REQUIRE_NOTHROW(mapnik::filter::filter_image(im, "scale-hsla(0.0,1.5,-1.0,1.0,-1.0,2.0,1.0,1.0)"););
+    REQUIRE_NOTHROW(mapnik::filter::filter_image(im, "scale-hsla(0.0,1.5,-1.0,1.0,-1.0,2.0,1.0,1.0)"));
 
     CHECK(im(0,0) == 0xff0000ff);
     CHECK(im(0,1) == 0xffefeff4);

test/unit/imaging/image_io_test.cpp

@@ -16,6 +16,7 @@
 #include <mapnik/warning_ignore.hpp>
 #include <boost/format.hpp>
 #include <boost/filesystem/convenience.hpp>
+#include <boost/optional/optional_io.hpp>
 #pragma GCC diagnostic pop
 
 inline void make_directory(std::string const& dir) {
@@ -65,7 +66,7 @@ SECTION("readers") {
         REQUIRE( mapnik::util::exists( should_throw ) );
         type = mapnik::type_from_filename(should_throw);
         REQUIRE( type );
-        REQUIRE_THROWS(std::unique_ptr<mapnik::image_reader> reader(mapnik::get_image_reader(should_throw,*type)));
+        REQUIRE_THROWS(mapnik::get_image_reader(should_throw,*type));
 
         // actually a png so jpeg reader should throw
         should_throw = "./test/data/images/landusepattern.jpg";
@@ -84,7 +85,7 @@ SECTION("readers") {
 
 #endif
 
-        REQUIRE_THROWS(mapnik::image_rgba8 im(-10,-10)); // should throw rather than overflow
+        REQUIRE_THROWS(mapnik::image_rgba8(-10,-10)); // should throw rather than overflow
 
 #if defined(HAVE_CAIRO)
         mapnik::cairo_surface_ptr image_surface(
@@ -103,13 +104,13 @@ SECTION("readers") {
         REQUIRE( mapnik::util::exists( should_throw ) );
         type = mapnik::type_from_filename(should_throw);
         REQUIRE( type );
-        REQUIRE_THROWS(std::unique_ptr<mapnik::image_reader> reader(mapnik::get_image_reader(should_throw,*type)));
+        REQUIRE_THROWS(mapnik::get_image_reader(should_throw,*type));
 
         should_throw = "./test/data/images/xcode-CgBI.png";
         REQUIRE( mapnik::util::exists( should_throw ) );
         type = mapnik::type_from_filename(should_throw);
         REQUIRE( type );
-        REQUIRE_THROWS(std::unique_ptr<mapnik::image_reader> reader(mapnik::get_image_reader(should_throw,*type)));
+        REQUIRE_THROWS(mapnik::get_image_reader(should_throw,*type));
 #endif
 
 #if defined(HAVE_TIFF)
@@ -117,7 +118,7 @@ SECTION("readers") {
         REQUIRE( mapnik::util::exists( should_throw ) );
         type = mapnik::type_from_filename(should_throw);
         REQUIRE( type );
-        REQUIRE_THROWS(std::unique_ptr<mapnik::image_reader> reader(mapnik::get_image_reader(should_throw,*type)));
+        REQUIRE_THROWS(mapnik::get_image_reader(should_throw,*type));
 #endif
 
 #if defined(HAVE_WEBP)
@@ -125,7 +126,7 @@ SECTION("readers") {
         REQUIRE( mapnik::util::exists( should_throw ) );
         type = mapnik::type_from_filename(should_throw);
         REQUIRE( type );
-        REQUIRE_THROWS(std::unique_ptr<mapnik::image_reader> reader(mapnik::get_image_reader(should_throw,*type)));
+        REQUIRE_THROWS(mapnik::get_image_reader(should_throw,*type));
 #endif
     }
     catch (std::exception const & ex)

test/unit/run.cpp

@@ -8,33 +8,22 @@
 
 #include "cleanup.hpp" // run_cleanup()
 
-std::string plugin_path;
 
-inline void set_plugin_path(Catch::ConfigData&, std::string const& _plugin_path ) {
+int main (int argc, char** argv)
-    plugin_path = _plugin_path;
-}
-
-std::string working_dir;
-
-inline void set_working_dir(Catch::ConfigData&, std::string const& _working_dir ) {
-    working_dir = _working_dir;
-}
-
-
-int main (int argc, char* const argv[])
 {
     Catch::Session session;
+    std::string plugin_path;
+    std::string working_dir;
+    auto cli = session.cli()
+        |
+        Catch::clara::Opt(plugin_path, "plugins")
+        ["-p"]["--plugins"] ("path to mapnik plugins")
+        |
+        Catch::clara::Opt(working_dir, "working directory")
+        ["-C"]["--working-directory"] ("change working directory")
+        ;
 
-    auto & cli = session.cli();
+    session.cli(cli);
-
-    cli["-p"]["--plugins"]
-        .describe("path to mapnik plugins")
-        .bind(&set_plugin_path, "plugins");
-
-    cli["-C"]["--working-directory"]
-        .describe("change working directory")
-        .bind(&set_working_dir, "working directory");
-
     int result = session.applyCommandLine(argc, argv);
 
     if (!plugin_path.empty())