ENH: Added test for executables with plugins that use an API exported by the executable itself.

Tests/Plugin/CMakeLists.txt

+PROJECT(Plugin)
+
+# Test per-target output directory properties.
+SET(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${Plugin_BINARY_DIR}/bin)
+SET(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${Plugin_BINARY_DIR}/lib/plugin)
+SET(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${Plugin_BINARY_DIR}/lib/static)
+
+# We need the dynamic loader support from KWSys to load the plugin in
+# the executable.
+SET(KWSYS_NAMESPACE kwsys)
+SET(KWSYS_HEADER_ROOT ${Plugin_BINARY_DIR}/include)
+SET(KWSYS_USE_DynamicLoader 1)
+ADD_SUBDIRECTORY(${Plugin_SOURCE_DIR}/../../Source/kwsys src/kwsys)
+INCLUDE_DIRECTORIES(
+  ${Plugin_BINARY_DIR}/include
+  ${Plugin_SOURCE_DIR}/include
+  )
+
+# Create an executable that exports an API for use by plugins.
+ADD_EXECUTABLE(example_exe src/example_exe.cxx)
+SET_TARGET_PROPERTIES(example_exe PROPERTIES
+  ENABLE_EXPORTS 1
+  OUTPUT_NAME example
+  )
+TARGET_LINK_LIBRARIES(example_exe kwsys)
+
+# Create a plugin that uses the API provided by the executable.
+# This module "links" to the executable to use the symbols.
+ADD_LIBRARY(example_mod_1 MODULE src/example_mod_1.c)
+TARGET_LINK_LIBRARIES(example_mod_1 example_exe)
+
+# TODO:
+#  - create a plugin that links to a static lib
+#  - create a plugin that links to a shared lib

Tests/Plugin/include/example.h

+#ifndef example_h
+#define example_h
+
+#if defined(_WIN32)
+# if defined(example_exe_EXPORTS)
+#  define EXAMPLE_EXPORT __declspec(dllexport)
+# else
+#  define EXAMPLE_EXPORT __declspec(dllimport)
+# endif
+#else
+# define EXAMPLE_EXPORT
+#endif
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+EXAMPLE_EXPORT int example_exe_function(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

Tests/Plugin/src/example_exe.cxx

+#include <example.h>
+
+#include <kwsys/DynamicLoader.hxx>
+#include <kwsys/ios/iostream>
+#include <kwsys/stl/string>
+
+#include <stdio.h>
+
+// Implement the ABI used by plugins.
+extern "C" int example_exe_function()
+{
+  kwsys_ios::cout << "hello" << kwsys_ios::endl;
+  return 123;
+}
+
+#ifdef CMAKE_INTDIR
+# define CONFIG_DIR "/" CMAKE_INTDIR
+#else
+# define CONFIG_DIR ""
+#endif
+
+int main()
+{
+  kwsys_stl::string libName = "lib/plugin" CONFIG_DIR "/";
+  libName += kwsys::DynamicLoader::LibPrefix();
+  libName += "example_mod_1";
+  libName += kwsys::DynamicLoader::LibExtension();
+  kwsys::DynamicLoader::LibraryHandle handle =
+    kwsys::DynamicLoader::OpenLibrary(libName.c_str());
+  if(!handle)
+    {
+    kwsys_ios::cerr << "Could not open plugin \""
+                    << libName << "\"!" << kwsys_ios::endl;
+    return 1;
+    }
+  kwsys::DynamicLoader::SymbolPointer sym =
+    kwsys::DynamicLoader::GetSymbolAddress(handle, "example_mod_1_function");
+  if(!sym)
+    {
+    kwsys_ios::cerr
+      << "Could not get plugin symbol \"example_mod_1_function\"!"
+      << kwsys_ios::endl;
+    return 1;
+    }
+  int(*f)() = reinterpret_cast<int(*)()>(sym);
+  if(f() != (123+456))
+    {
+    kwsys_ios::cerr << "Incorrect return value from plugin!"
+                    << kwsys_ios::endl;
+    return 1;
+    }
+  return 0;
+}

Tests/Plugin/src/example_mod_1.c

+#include <example.h>
+
+#include <stdio.h>
+
+#if defined(_WIN32)
+# define MODULE_EXPORT __declspec(dllexport)
+#else
+# define MODULE_EXPORT
+#endif
+
+MODULE_EXPORT int example_mod_1_function()
+{
+  int result = example_exe_function() + 456;
+  printf("world\n");
+  return result;
+}