Improve gotcha download/install process

CMakeLists.txt

@@ -116,9 +116,8 @@ endif()
 
 if (WITH_GOTCHA)
   set(CALIPER_HAVE_GOTCHA TRUE)
-  set(GOTCHA_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR}/ext/gotcha/gotcha-build/include)
-  set(GOTCHA_LIBRARY ${CMAKE_CURRENT_BINARY_DIR}/ext/gotcha/gotcha-build/lib/libgotcha.so)
-  list(APPEND CALIPER_EXTERNAL_LIBS ${GOTCHA_LIBRARY})
+  set(GOTCHA_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR}/ext/gotcha/gotcha-download/gotcha-src/include)
+  list(APPEND CALIPER_EXTERNAL_LIBS gotcha)
 endif()
 
 find_package(Threads)

ext/gotcha/CMakeLists.txt

@@ -1,8 +1,26 @@
-include(ExternalProject)
+#
+# --- gotcha: download gotcha at configure time
+#
+
+configure_file(gotcha-download_CMakeLists.txt.in gotcha-download/CMakeLists.txt)
 
-ExternalProject_Add(gotcha
-  GIT_REPOSITORY "https://www.github.com/LLNL/gotcha"
-  CMAKE_ARGS     -DCMAKE_INSTALL_PREFIX=${CMAKE_CURRENT_BINARY_DIR}/gotcha-build -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER} -DGOTCHA_ENABLE_TESTS=Off
-  BUILD_COMMAND "make"
-)
+execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
+  RESULT_VARIABLE   result
+  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/gotcha-download)
 
+if (result)
+  message(FATAL_ERROR "CMake step for gotcha failed: ${result}")
+endif()
+
+execute_process(COMMAND ${CMAKE_COMMAND} --build .
+  RESULT_VARIABLE   result
+  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/gotcha-download)
+
+if (result)
+  message(FATAL_ERROR "Build step for gotcha failed: ${result}")
+endif()
+
+# Add gotcha directories. Defines gtest and gtest-main targets.
+add_subdirectory(
+  ${CMAKE_CURRENT_BINARY_DIR}/gotcha-download/gotcha-src
+  ${CMAKE_CURRENT_BINARY_DIR}/gotcha-download/gotcha-build)

ext/gotcha/gotcha-download_CMakeLists.txt.in

@@ -0,0 +1,15 @@
+cmake_minimum_required(VERSION 3.0)
+
+project(libgotcha NONE)
+
+include(ExternalProject)
+ExternalProject_Add(libgotcha
+  GIT_REPOSITORY    "https://github.com/LLNL/gotcha.git"
+  SOURCE_DIR        "${CMAKE_CURRENT_BINARY_DIR}/gotcha-download/gotcha-src"
+  BINARY_DIR        "${CMAKE_CURRENT_BINARY_DIR}/gotcha-download/gotcha-build"
+  CMAKE_ARGS        ""
+  CONFIGURE_COMMAND ""
+  BUILD_COMMAND     ""
+  INSTALL_COMMAND   ""
+  TEST_COMMAND      ""
+)