9. CMake

CMake

The library can also be installed using CMake. Version of CMake must be 3.0+ and can be checked by --version:

> cmake --version
cmake version 3.3.1

CMake suite maintained and supported by Kitware (kitware.com/cmake).

Generate

Generate project in _builds directory using CMakeLists.txt from current (.) directory, run one of the commands depending on the OS and generator you need:

> cmake -H. -B_builds -DCMAKE_BUILD_TYPE=Release # Default generator is Makefile for *nix platform
> cmake -H. -B_builds -GXcode # Xcode generator on OS X (multi-config, no need for CMAKE_BUILD_TYPE)
> cmake -H. -B_builds -G"Visual Studio 12 2013" # Visual Studio IDE, Windows, multi-config

or toolchains:

> cmake -H. -B_builds -DCMAKE_TOOLCHAIN_FILE=/path/to/iOS.cmake -GXcode
> cmake -H. -B_builds -DCMAKE_TOOLCHAIN_FILE=/path/to/android.cmake -DCMAKE_BUILD_TYPE=Release

To add examples use SPDLOG_BUILD_EXAMPLES=ON option:

> cmake -H. -B_builds -DSPDLOG_BUILD_EXAMPLES=ON -DCMAKE_BUILD_TYPE=Release

Build/test

Open generated project and run build/test targets. Also command line can be used too:

> cmake --build _builds --config Release
> cd _builds && ctest -VV -C Release

Install

Headers can be installed along with the config files so library can be found by find_package(spdlog CONFIG REQUIRED):

[spdlog]> cmake -H. -B_builds -DCMAKE_INSTALL_PREFIX=/path/to/install -DCMAKE_BUILD_TYPE=Release
[spdlog]> cmake --build _builds --target install

Usage can be tested by building examples as a stand-alone project:

[spdlog/examples]> cmake -H. -B_builds -DCMAKE_PREFIX_PATH=/path/to/install -DCMAKE_BUILD_TYPE=Release
[spdlog/examples]> cmake --build _builds

Cross-compiling for Android with CMake 3.7

Cross-compiling with CMake is reported working using CMake version 3.7 which includes native support for configuring the toolchain with Android NDK and SDK (https://cmake.org/cmake/help/v3.7/manual/cmake-toolchains.7.html#cross-compiling-for-android). Please note that spdlog targets older versions of CMake and this example is a community contribution.

Below is an example on to configure and build spdlog using the Android NDK:

> git clone https://github.com/gabime/spdlog
> mkdir build
> cd build 
> cmake ../spdlog \
  -DCMAKE_SYSTEM_NAME=Android \
  -DCMAKE_SYSTEM_VERSION=21 \
  -DCMAKE_ANDROID_ARCH_ABI="armeabi-v7a" \
  -DCMAKE_ANDROID_ARM_NEON=ON \
  -DCMAKE_ANDROID_NDK=$HOME/Android/Ndk/android-ndk-r13b/
> cmake --build .

See the CMake documentation (link above) for the meaning of the CMake configuration options used in the example.

Use as static library with ExternalProject_Add as git submodule

This is a short example if you want to use a static library, actually called libspdlogd.a, in your project using CMake.

cd project_dir\lib
git submodule add https://github.com/gabime/spdlog
cd spdlog
git checkout v1.9.2
...

ExternalProject_Add(spdlog
    PREFIX spdlog
    SOURCE_DIR ${PROJECT_SOURCE_DIR}/lib/spdlog
    CMAKE_ARGS -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}
    -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
    -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
    -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE}
    -DCMAKE_INSTALL_PREFIX=${STAGING_DIR}
    -DSPDLOG_BUILD_SHARED=OFF
)

later also add:

add_dependencies(${PROJECT_NAME} spdlog)

And finally use it like this:

PUBLIC ${STAGING_DIR}/include/ # spdlog

Inside the C++/H files you can:

#include "spdlog/spdlog.h"

Using spdlog in a shared library

When building a shared library, CMAKE_POSITION_INDEPENDENT_CODE has to be set to TRUE before adding the spdlog subdirectory.

Full example:

cmake_minimum_required(VERSION 3.10)

project(cmake_test)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED TRUE)
set(CMAKE_POSITION_INDEPENDENT_CODE TRUE)

add_subdirectory("${CMAKE_SOURCE_DIR}/spdlog")

file(GLOB_RECURSE SOURCES "${CMAKE_CURRENT_SOURCE_DIR}/src/*.cpp")
add_library(test SHARED ${SOURCES})
target_include_directories(test PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/src")

target_link_libraries(test PRIVATE spdlog::spdlog)