Fixed issues when including Polaris in an external CMake project.

.github/workflows/release_build.yml

@@ -117,6 +117,14 @@ jobs:
  cd cmake_build
  MSBuild.exe p1_polaris_client.sln
 
+ - name: Build External Project Example (CMake, Linux)
+ if: matrix.tool == 'cmake' && matrix.os == 'ubuntu-latest'
+ run: |
+ mkdir examples/external_cmake_project/build
+ cd examples/external_cmake_project/build
+ cmake ..
+ make
+
  # Bazel build support.
  - name: Use Bazel 4.2.2
  if: matrix.tool == 'bazel'
@@ -205,11 +213,11 @@ jobs:
  make -j
 
  # CMake build support.
- - name: Install CMake 3.16.x
+ - name: Install CMake 3.18.x
  if: matrix.tool == 'cmake'
  uses: jwlawson/actions-setup-cmake@v1.4
  with:
- cmake-version: '3.16.x'
+ cmake-version: '3.18.x'
 
  - name: Setup Build (CMake)
  if: matrix.tool == 'cmake'
@@ -231,6 +239,14 @@ jobs:
  cd cmake_build
  MSBuild.exe p1_polaris_c_client.sln
 
+ - name: Build External Project Example (CMake, Linux)
+ if: matrix.tool == 'cmake' && matrix.os == 'ubuntu-latest'
+ run: |
+ mkdir examples/external_cmake_project/build
+ cd examples/external_cmake_project/build
+ cmake ..
+ make
+
  # Bazel build support.
  - name: Use Bazel 4.2.2
  if: matrix.tool == 'bazel'

.gitignore

@@ -6,6 +6,8 @@ build/
 
 # Python
 *.pyc
+.idea/
+venv/
 
 # Visual Studio Code
 .vscode

CMakeLists.txt

@@ -1,15 +1,25 @@
 # Copyright (C) Point One Navigation - All Rights Reserved
-project(p1_polaris_client)
-
-cmake_minimum_required(VERSION 3.3.2)
+cmake_minimum_required(VERSION 3.6)
 
-set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/")
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_SOURCE_DIR}/cmake/")
 
 # Option definitions.
 option(BUILD_SHARED_LIBS "Build shared libraries instead of static libraries."
  ON)
 
-option(BUILD_EXAMPLES "Build example applications." ON)
+option(POLARIS_BUILD_EXAMPLES "Build example applications." ON)
+
+# Backwards compatibility. BUILD_EXAMPLES is deprecated and may be removed in a
+# future release.
+if (DEFINED BUILD_EXAMPLES AND BUILD_EXAMPLES)
+ set(POLARIS_BUILD_EXAMPLES ${BUILD_EXAMPLES})
+endif()
+
+# Set toolchain parameters before calling project().
+set(CMAKE_CXX_STANDARD 11)
+
+# Define the project and setup the compiler toolchain.
+project(p1_polaris_client)
 
 # Set compilation flags.
 if (MSVC)
@@ -39,15 +49,12 @@ include_directories(${GLOG_INCLUDE_DIRS})
 
 # Add the C library, used by the C++ library.
 add_subdirectory(c)
-include_directories(${PROJECT_SOURCE_DIR}/c/src)
-
-# Add the source directory to the include path.
-include_directories(${PROJECT_SOURCE_DIR}/src)
 
 # Polaris client C++ library - all messages and supporting code.
 add_library(polaris_cpp_client
  src/point_one/polaris/polaris_client.cc
  src/point_one/polaris/polaris_interface.cc)
+target_include_directories(polaris_client PUBLIC ${PROJECT_SOURCE_DIR}/src)
 if (MSVC)
  target_compile_definitions(polaris_cpp_client PRIVATE BUILDING_DLL)
 endif()
@@ -69,6 +76,6 @@ install(DIRECTORY src/point_one DESTINATION include
 # Example Applications
 ################################################################################
 
-if (BUILD_EXAMPLES)
+if (POLARIS_BUILD_EXAMPLES)
  add_subdirectory(examples)
 endif()

c/CMakeLists.txt

@@ -1,19 +1,26 @@
 # Copyright (C) Point One Navigation - All Rights Reserved
-project(p1_polaris_c_client)
-
-cmake_minimum_required(VERSION 3.3.2)
+cmake_minimum_required(VERSION 3.6)
 
 # Option definitions.
 option(BUILD_SHARED_LIBS "Build shared libraries instead of static libraries."
  ON)
 
-option(BUILD_EXAMPLES "Build example applications." ON)
+option(POLARIS_BUILD_EXAMPLES "Build example applications." ON)
 
 option(POLARIS_ENABLE_PRINT
  "Enable Polaris debug/trace print messages." ON)
 
 option(POLARIS_ENABLE_TLS "Enable TLS support when connecting to Polaris." ON)
 
+# Backwards compatibility. BUILD_EXAMPLES is deprecated and may be removed in a
+# future release.
+if (DEFINED BUILD_EXAMPLES AND BUILD_EXAMPLES)
+ set(POLARIS_BUILD_EXAMPLES ${BUILD_EXAMPLES})
+endif()
+
+# Define the project and setup the compiler toolchain.
+project(p1_polaris_c_client)
+
 # Set compilation flags.
 if (MSVC)
  add_compile_options(/W4 /WX)
@@ -38,13 +45,11 @@ endif()
 # Library Definitions
 ################################################################################
 
-# Add the source directory to the include path.
-include_directories(${PROJECT_SOURCE_DIR}/src)
-
 # Polaris client C library - all messages and supporting code.
 add_library(polaris_client
  src/point_one/polaris/polaris.c
  src/point_one/polaris/polaris_internal.c)
+target_include_directories(polaris_client PUBLIC ${PROJECT_SOURCE_DIR}/src)
 if (MSVC)
  target_compile_definitions(polaris_client PRIVATE BUILDING_DLL)
 endif()
@@ -65,6 +70,6 @@ install(DIRECTORY src/point_one DESTINATION include
 # Example Applications
 ################################################################################
 
-if (BUILD_EXAMPLES)
+if (POLARIS_BUILD_EXAMPLES)
  add_subdirectory(examples)
 endif()

c/examples/external_cmake_project/CMakeLists.txt

@@ -0,0 +1,52 @@
+################################################################################
+# This is a simple example of how to import the Polaris client library in
+# your own project using the CMake FetchContent feature. We strongly encourage
+# you to use FetchContent to download Polaris client from the publicly available
+# source code.
+#
+# Alternatively, you may choose to use a git submodule to import the source code
+# into your repository. We do not recommend copying the Polaris client souce
+# code directly into your repository. Doing so makes it much more difficult to
+# receive updates as new features and improvements are released.
+################################################################################
+
+# Note: CMake 3.18 or newer required to use SOURCE_SUBDIR below in order to
+# include just the Polaris C library and not the top-level C++ library.
+cmake_minimum_required(VERSION 3.18)
+
+project(polaris_usage_example C)
+
+# Use FetchContent to import the Polaris client C library using Git.
+#
+# Note that we always recommend using a specific version of the library in your
+# code by specifying a git tag (e.g., `GIT_TAG v1.3.1`), and updating that as
+# new versions are released. That way, you can be sure that your code is always
+# built with a known version of Polaris client. If you prefer, however, you can
+# set the GIT_TAG to track the latest changes by setting `GIT_TAG master` below.
+#
+# We explicitly disable example applications from the Polaris client library by
+# setting POLARIS_BUILD_EXAMPLES to OFF below. We only want to build the library
+# and make the fusion_engine_client CMake target available here. By default, if
+# we do not tell it otherwise, FetchContent_MakeAvailable() will also import all
+# of the example applications in polaris/c/examples/.
+#
+# It is important to specify it as an INTERNAL variable. If you do not do this,
+# the option definition in the fusion-engine-client CMakeLists.txt file will
+# override this value and enable the example applications anyway. This is a
+# result of CMP0077, which was added in CMake 3.13.
+include(FetchContent)
+FetchContent_Declare(
+ polaris
+ #GIT_REPOSITORY https://github.com/PointOneNav/polaris.git
+ #GIT_TAG v1.3.1
+ SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../../..
+ SOURCE_SUBDIR c
+)
+set(POLARIS_BUILD_EXAMPLES OFF CACHE INTERNAL "")
+FetchContent_MakeAvailable(polaris)
+
+# Now we define an example application that uses the Polaris client library.
+# In your own code, you can link any add_executable() or add_library() target
+# with polaris_client by calling target_link_libraries() as shown.
+add_executable(example_app main.c)
+target_link_libraries(example_app PUBLIC polaris_client)

c/examples/external_cmake_project/main.c

@@ -0,0 +1,12 @@
+/**************************************************************************/ /**
+ * @brief Example external cmake project.
+ *
+ * Copyright (c) Point One Navigation - All Rights Reserved
+ ******************************************************************************/
+
+#include <point_one/polaris/portability.h>
+
+int main(int argc, const char* argv[]) {
+ P1_printf("Hello, world!\n");
+ return 0;
+}

examples/external_cmake_project/CMakeLists.txt

@@ -0,0 +1,51 @@
+################################################################################
+# This is a simple example of how to import the Polaris client library in
+# your own project using the CMake FetchContent feature. We strongly encourage
+# you to use FetchContent to download Polaris client from the publicly available
+# source code.
+#
+# Alternatively, you may choose to use a git submodule to import the source code
+# into your repository. We do not recommend copying the Polaris client souce
+# code directly into your repository. Doing so makes it much more difficult to
+# receive updates as new features and improvements are released.
+################################################################################
+
+cmake_minimum_required(VERSION 3.6)
+
+set(CMAKE_CXX_STANDARD 11)
+
+project(polaris_usage_example C CXX)
+
+# Use FetchContent to import the Polaris client C library using Git.
+#
+# Note that we always recommend using a specific version of the library in your
+# code by specifying a git tag (e.g., `GIT_TAG v1.3.1`), and updating that as
+# new versions are released. That way, you can be sure that your code is always
+# built with a known version of Polaris client. If you prefer, however, you can
+# set the GIT_TAG to track the latest changes by setting `GIT_TAG master` below.
+#
+# We explicitly disable example applications from the Polaris client library by
+# setting POLARIS_BUILD_EXAMPLES to OFF below. We only want to build the library
+# and make the fusion_engine_client CMake target available here. By default, if
+# we do not tell it otherwise, FetchContent_MakeAvailable() will also import all
+# of the example applications in polaris/examples/.
+#
+# It is important to specify it as an INTERNAL variable. If you do not do this,
+# the option definition in the fusion-engine-client CMakeLists.txt file will
+# override this value and enable the example applications anyway. This is a
+# result of CMP0077, which was added in CMake 3.13.
+include(FetchContent)
+FetchContent_Declare(
+ polaris
+ #GIT_REPOSITORY https://github.com/PointOneNav/polaris.git
+ #GIT_TAG v1.3.1
+ SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../..
+)
+set(POLARIS_BUILD_EXAMPLES OFF CACHE INTERNAL "")
+FetchContent_MakeAvailable(polaris)
+
+# Now we define an example application that uses the Polaris client library.
+# In your own code, you can link any add_executable() or add_library() target
+# with polaris_client by calling target_link_libraries() as shown.
+add_executable(example_app main.cc)
+target_link_libraries(example_app PUBLIC polaris_cpp_client)

examples/external_cmake_project/main.cc

@@ -0,0 +1,16 @@
+/**************************************************************************/ /**
+ * @brief Example external cmake project.
+ *
+ * Copyright (c) Point One Navigation - All Rights Reserved
+ ******************************************************************************/
+
+#include <point_one/polaris/portability.h>
+#include <point_one/polaris/polaris_client.h>
+
+using namespace point_one::polaris;
+
+int main(int argc, const char* argv[]) {
+ P1_printf("Hello, world!\n");
+ P1_printf("sizeof(PolarisClient): %zu B\n", sizeof(PolarisClient));
+ return 0;
+}