4 files changed, 106 insertions, 0 deletions
diff --git a/libhello/buildfile b/libhello/buildfile
new file mode 100644
index 0000000..e65edde
--- /dev/null
+++ b/libhello/buildfile
@@ -0,0 +1,26 @@
+import int_libs = libformat%lib{format}
+import imp_libs = libprint%lib{print}
+
+lib{hello}: {hxx cxx}{hello} hxx{export} $imp_libs $int_libs
+
+# For pre-releases use the complete version to make sure they cannot be used
+# in place of another pre-release or the final version.
+#
+if $version.pre_release
+  lib{hello}: bin.lib.version = @"-$version.project_id"
+else
+  lib{hello}: bin.lib.version = @"-$version.major.$version.minor"
+
+cxx.poptions =+ "-I$out_root" "-I$src_root"
+obja{*}: cxx.poptions += -DLIBHELLO_STATIC_BUILD
+objs{*}: cxx.poptions += -DLIBHELLO_SHARED_BUILD
+
+lib{hello}: cxx.export.poptions = "-I$out_root" "-I$src_root"
+liba{hello}: cxx.export.poptions += -DLIBHELLO_STATIC
+libs{hello}: cxx.export.poptions += -DLIBHELLO_SHARED
+
+lib{hello}: cxx.export.libs = $int_libs
+
+# Install into the libhello/ subdirectory of, say, /usr/include/.
+#
+install.include = $install.include/libhello/
diff --git a/libhello/export.hxx b/libhello/export.hxx
new file mode 100644
index 0000000..e6c723e
--- /dev/null
+++ b/libhello/export.hxx
@@ -0,0 +1,36 @@
+// file: libhello/export.hxx -*- C++ -*-
+
+#pragma once
+
+// Normally we don't export class templates (but do complete specializations),
+// inline functions, and classes with only inline member functions. Exporting
+// classes that inherit from non-exported/imported bases (e.g., std::string)
+// will end up badly. The only known workarounds are to not inherit or to not
+// export. Also, MinGW GCC doesn't like seeing non-exported function being
+// used before their inline definition. The workaround is to reorder code. In
+// the end it's all trial and error.
+
+#if defined(LIBHELLO_STATIC)         // Using static.
+#  define LIBHELLO_EXPORT
+#elif defined(LIBHELLO_STATIC_BUILD) // Building static.
+#  define LIBHELLO_EXPORT
+#elif defined(LIBHELLO_SHARED)       // Using shared.
+#  ifdef _WIN32
+#    define LIBHELLO_EXPORT __declspec(dllimport)
+#  else
+#    define LIBHELLO_EXPORT
+#  endif
+#elif defined(LIBHELLO_SHARED_BUILD) // Building shared.
+#  ifdef _WIN32
+#    define LIBHELLO_EXPORT __declspec(dllexport)
+#  else
+#    define LIBHELLO_EXPORT
+#  endif
+#else
+// If none of the above macros are defined, then we assume we are being used
+// by some third-party build system that cannot/doesn't signal the library
+// type. Note that this fallback works for both static and shared but in case
+// of shared will be sub-optimal compared to having dllimport.
+//
+#  define LIBHELLO_EXPORT            // Using static or shared.
+#endif
diff --git a/libhello/hello.cxx b/libhello/hello.cxx
new file mode 100644
index 0000000..f7e3b7f
--- /dev/null
+++ b/libhello/hello.cxx
@@ -0,0 +1,16 @@
+// file: libhello/hello.cxx -*- C++ -*-
+
+#include <libhello/hello.hxx>
+
+#include <libprint/print.hxx>
+
+using namespace std;
+
+namespace hello
+{
+  void
+  say_formatted (const string& m)
+  {
+    print (m);
+  }
+}
diff --git a/libhello/hello.hxx b/libhello/hello.hxx
new file mode 100644
index 0000000..ccc43c2
--- /dev/null
+++ b/libhello/hello.hxx
@@ -0,0 +1,28 @@
+// file: libhello/hello.hxx -*- C++ -*-
+
+#pragma once
+
+#include <string>
+
+#include <libformat/format.hxx>
+
+#include <libhello/export.hxx>
+
+namespace hello
+{
+  // If you compare this interface to version 1.0, then you will notice that
+  // while it is API/source-compatible (the signature of say() is unchanged)
+  // it is not ABI/binary-compatible (say() is now inline).
+  //
+  // Notice also that inline say() calls format() which means libformat is an
+  // interface dependency of libhello.
+
+  LIBHELLO_EXPORT void
+  say_formatted (const std::string& message);
+
+  inline void
+  say (const std::string& name)
+  {
+    say_formatted (format ("Hello", name));
+  }
+}