Improve CMake build system

New build options
-----------------

* Add option BUILD_TESTING by default ON
See https://cmake.org/cmake/help/v2.8.12/cmake.html#module:CTest

* Simplify library type selection using standard option BUILD_SHARED_LIBS
See https://cmake.org/cmake/help/v3.0/variable/BUILD_SHARED_LIBS.html

yamlConfig.cmake
----------------

* Generate and install yamlConfig.cmake, yamlConfigVersion.cmake and yamlTargets.cmake

* Bump CMake version and explicitly associate include dirs with targets
See https://cmake.org/cmake/help/v3.0/manual/cmake-buildsystem.7.html#include-directories-and-usage-requirements

* Ensure building against libyaml using "find_package(yaml)" uses expected compile options: Set HAVE_CONFIG_H
as private compile option, YAML_DECLARE_STATIC as public

Testing
-------

* Build all examples from "tests" directory

CMake Best practices
--------------------

* configure "config.h" based on version info found in CMakeLists.txt

* Ensure buildsystem re-generation listing sources (best-practice)

It is not recommended to use GLOB to collect a list of source files from
the source tree. If no CMakeLists.txt file changes when a source is added
or removed then the generated build system cannot know when to ask CMake
to regenerate.

See https://cmake.org/cmake/help/v3.8/command/file.html

Compilation warnings
--------------------

* Set _CRT_SECURE_NO_WARNINGS if building using VisualStudio

This will avoid warnings like this one:

```
C:\projects\libyaml\tests\run-emitter.c(268): warning C4996: 'fopen':
This function or variable may be unsafe. Consider using fopen_s instead.
To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for
details.
```

Continuous Integration
----------------------

* travis: Install CMake >= 3.x using scikit-ci-addons

* Add comments to appveyor.yml and run-tests.sh

1 files changed, 147 insertions, 15 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e47f5ef..5e85aef 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,5 @@
-# Minimal CMake project for building a static library under Windows.
 
-cmake_minimum_required (VERSION 2.8)
+cmake_minimum_required(VERSION 3.0)
 project (yaml C)
 
 set (YAML_VERSION_MAJOR 0)
@@ -8,21 +7,154 @@ set (YAML_VERSION_MINOR 1)
 set (YAML_VERSION_PATCH 7)
 set (YAML_VERSION_STRING "${YAML_VERSION_MAJOR}.${YAML_VERSION_MINOR}.${YAML_VERSION_PATCH}")
 
-file (GLOB SRC src/*.c)
+option(BUILD_SHARED_LIBS "Build libyaml as a shared library" OFF)
 
-include_directories (include win32)
-add_library (yaml SHARED ${SRC})
-set_target_properties(yaml PROPERTIES COMPILE_FLAGS "-DYAML_DECLARE_EXPORT -DHAVE_CONFIG_H")
+#
+# Output directories for a build tree
+#
+if(NOT DEFINED CMAKE_RUNTIME_OUTPUT_DIRECTORY)
+  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+endif()
 
-add_library (yaml_static STATIC ${SRC})
-set_target_properties(yaml_static PROPERTIES COMPILE_FLAGS "-DYAML_DECLARE_STATIC -DHAVE_CONFIG_H")
+#
+# Install relative directories
+#
+if(NOT DEFINED INSTALL_LIB_DIR)
+  set(INSTALL_LIB_DIR lib)
+endif()
+if(NOT DEFINED INSTALL_BIN_DIR)
+  set(INSTALL_BIN_DIR bin)
+endif()
+if(NOT DEFINED INSTALL_INCLUDE_DIR)
+  set(INSTALL_INCLUDE_DIR include)
+endif()
+if(NOT DEFINED INSTALL_CMAKE_DIR)
+  set(INSTALL_CMAKE_DIR cmake)
+endif()
 
-add_executable (test-version tests/test-version.c)
-target_link_libraries(test-version yaml)
-add_test(NAME version COMMAND test-version)
+#
+# Build library
+#
+set(SRCS
+  src/api.c
+  src/dumper.c
+  src/emitter.c
+  src/loader.c
+  src/parser.c
+  src/reader.c
+  src/scanner.c
+  src/writer.c
+  )
 
-add_executable (test-reader tests/test-reader.c)
-target_link_libraries(test-reader yaml)
-add_test(NAME reader COMMAND test-reader)
+set(config_h ${CMAKE_CURRENT_BINARY_DIR}/include/config.h)
+configure_file(
+  cmake/config.h.in
+  ${config_h}
+  )
 
-enable_testing()
+add_library(yaml ${SRCS})
+
+if(NOT BUILD_SHARED_LIBS)
+  set_target_properties(yaml
+    PROPERTIES OUTPUT_NAME yaml_static
+    )
+endif()
+
+set_target_properties(yaml
+  PROPERTIES DEFINE_SYMBOL YAML_DECLARE_EXPORT
+  )
+
+target_compile_definitions(yaml
+  PRIVATE HAVE_CONFIG_H
+  PUBLIC
+    $<$<NOT:$<BOOL:${BUILD_SHARED_LIBS}>>:YAML_DECLARE_STATIC>
+    $<$<BOOL:${MSVC}>:_CRT_SECURE_NO_WARNINGS>
+  )
+
+target_include_directories(yaml PUBLIC
+  $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+  $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>
+  $<INSTALL_INTERFACE:${INSTALL_INCLUDE_DIR}>
+  )
+
+#
+# Install rules
+#
+install(
+  FILES
+    include/yaml.h
+    ${config_h}
+  DESTINATION include COMPONENT Development
+  )
+
+install(
+  TARGETS yaml
+  EXPORT yamlTargets
+  RUNTIME DESTINATION "${INSTALL_BIN_DIR}" COMPONENT Runtime
+  LIBRARY DESTINATION "${INSTALL_LIB_DIR}" COMPONENT Development
+  ARCHIVE DESTINATION "${INSTALL_LIB_DIR}" COMPONENT Development
+  )
+
+#
+# Add tests
+#
+include(CTest) # This module defines BUILD_TESTING option
+if(BUILD_TESTING)
+  add_subdirectory(tests)
+endif()
+
+#
+# Generate 'yamlConfig.cmake', 'yamlConfigVersion.cmake' and 'yamlTargets.cmake'
+#
+include(CMakePackageConfigHelpers)
+
+# Configure 'yamlConfig.cmake' for a build tree
+set(CONFIG_DIR_CONFIG ${PROJECT_BINARY_DIR})
+set(config_file ${PROJECT_BINARY_DIR}/yamlConfig.cmake)
+configure_package_config_file(
+  yamlConfig.cmake.in
+  ${config_file}
+  INSTALL_DESTINATION ${PROJECT_BINARY_DIR}
+  PATH_VARS CONFIG_DIR_CONFIG
+  NO_CHECK_REQUIRED_COMPONENTS_MACRO
+  )
+
+# Configure 'yamlTargets.cmake' for a build tree
+export(TARGETS yaml
+  FILE ${PROJECT_BINARY_DIR}/yamlTargets.cmake
+  )
+
+# Configure and install 'yamlConfig.cmake' for an install tree
+set(CONFIG_DIR_CONFIG ${INSTALL_CMAKE_DIR})
+set(install_config_file ${PROJECT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/yamlConfig.cmake )
+configure_package_config_file(
+  yamlConfig.cmake.in
+  ${install_config_file}
+  INSTALL_DESTINATION ${CMAKE_INSTALL_PREFIX}/${INSTALL_CMAKE_DIR}
+  PATH_VARS CONFIG_DIR_CONFIG
+  NO_CHECK_REQUIRED_COMPONENTS_MACRO
+  )
+install(
+  FILES ${install_config_file}
+  DESTINATION ${INSTALL_CMAKE_DIR} COMPONENT Development
+  )
+
+# Configure and install 'yamlTargets.cmake' for an install tree
+install(EXPORT yamlTargets
+  FILE yamlTargets.cmake
+  DESTINATION ${INSTALL_CMAKE_DIR}
+  COMPONENT Development
+  )
+
+# Configure 'yamlConfigVersion.cmake' for a build tree
+set(config_version_file ${PROJECT_BINARY_DIR}/yamlConfigVersion.cmake)
+write_basic_package_version_file(
+    ${config_version_file}
+    VERSION ${YAML_VERSION_STRING}
+    COMPATIBILITY AnyNewerVersion
+)
+# ... and install for an install tree
+install(
+  FILES ${config_version_file}
+  DESTINATION ${INSTALL_CMAKE_DIR} COMPONENT Development
+  )