cpp-httplib/CMakeLists.txt

294 lines
12 KiB
CMake

#[[
Build options:
* BUILD_SHARED_LIBS (default off) builds as a shared library (if HTTPLIB_COMPILE is ON)
* HTTPLIB_USE_OPENSSL_IF_AVAILABLE (default on)
* HTTPLIB_USE_ZLIB_IF_AVAILABLE (default on)
* HTTPLIB_REQUIRE_OPENSSL (default off)
* HTTPLIB_REQUIRE_ZLIB (default off)
* HTTPLIB_USE_BROTLI_IF_AVAILABLE (default on)
* HTTPLIB_REQUIRE_BROTLI (default off)
* HTTPLIB_COMPILE (default off)
* BROTLI_USE_STATIC_LIBS - tells Cmake to use the static Brotli libs (only works if you have them installed).
* OPENSSL_USE_STATIC_LIBS - tells Cmake to use the static OpenSSL libs (only works if you have them installed).
-------------------------------------------------------------------------------
After installation with Cmake, a find_package(httplib) is available.
This creates a httplib::httplib target (if found).
It can be linked like so:
target_link_libraries(your_exe httplib::httplib)
The following will build & install for later use.
Linux/macOS:
mkdir -p build
cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
sudo cmake --build . --target install
Windows:
mkdir build
cd build
cmake ..
runas /user:Administrator "cmake --build . --config Release --target install"
-------------------------------------------------------------------------------
These variables are available after you run find_package(httplib)
* HTTPLIB_HEADER_PATH - this is the full path to the installed header (e.g. /usr/include/httplib.h).
* HTTPLIB_IS_USING_OPENSSL - a bool for if OpenSSL support is enabled.
* HTTPLIB_IS_USING_ZLIB - a bool for if ZLIB support is enabled.
* HTTPLIB_IS_USING_BROTLI - a bool for if Brotli support is enabled.
* HTTPLIB_IS_COMPILED - a bool for if the library is compiled, or otherwise header-only.
* HTTPLIB_INCLUDE_DIR - the root path to httplib's header (e.g. /usr/include).
* HTTPLIB_LIBRARY - the full path to the library if compiled (e.g. /usr/lib/libhttplib.so).
* httplib_VERSION or HTTPLIB_VERSION - the project's version string.
* HTTPLIB_FOUND - a bool for if the target was found.
Want to use precompiled headers (Cmake feature since v3.16)?
It's as simple as doing the following (before linking):
target_precompile_headers(httplib::httplib INTERFACE "${HTTPLIB_HEADER_PATH}")
-------------------------------------------------------------------------------
FindPython3 requires Cmake v3.12
ARCH_INDEPENDENT option of write_basic_package_version_file() requires Cmake v3.14
]]
cmake_minimum_required(VERSION 3.14.0 FATAL_ERROR)
# Get the user agent and use it as a version
# This gets the string with the user agent from the header.
# This is so the maintainer doesn't actually need to update this manually.
file(STRINGS httplib.h _raw_version_string REGEX "User\-Agent.*cpp\-httplib/([0-9]+\.?)+")
# Needed since git tags have "v" prefixing them.
# Also used if the fallback to user agent string is being used.
string(REGEX MATCH "([0-9]+\\.?)+" _httplib_version "${_raw_version_string}")
project(httplib VERSION ${_httplib_version} LANGUAGES CXX)
# Change as needed to set an OpenSSL minimum version.
# This is used in the installed Cmake config file.
set(_HTTPLIB_OPENSSL_MIN_VER "1.1.1")
# Allow for a build to require OpenSSL to pass, instead of just being optional
option(HTTPLIB_REQUIRE_OPENSSL "Requires OpenSSL to be found & linked, or fails build." OFF)
option(HTTPLIB_REQUIRE_ZLIB "Requires ZLIB to be found & linked, or fails build." OFF)
# Allow for a build to casually enable OpenSSL/ZLIB support, but silenty continue if not found.
# Make these options so their automatic use can be specifically disabled (as needed)
option(HTTPLIB_USE_OPENSSL_IF_AVAILABLE "Uses OpenSSL (if available) to enable HTTPS support." ON)
option(HTTPLIB_USE_ZLIB_IF_AVAILABLE "Uses ZLIB (if available) to enable Zlib compression support." ON)
# Lets you compile the program as a regular library instead of header-only
option(HTTPLIB_COMPILE "If ON, uses a Python script to split the header into a compilable header & source file (requires Python v3)." OFF)
# Just setting this variable here for people building in-tree
if(HTTPLIB_COMPILE)
set(HTTPLIB_IS_COMPILED TRUE)
endif()
option(HTTPLIB_REQUIRE_BROTLI "Requires Brotli to be found & linked, or fails build." OFF)
option(HTTPLIB_USE_BROTLI_IF_AVAILABLE "Uses Brotli (if available) to enable Brotli decompression support." ON)
# Defaults to static library
option(BUILD_SHARED_LIBS "Build the library as a shared library instead of static. Has no effect if using header-only." OFF)
if (BUILD_SHARED_LIBS AND WIN32 AND HTTPLIB_COMPILE)
# Necessary for Windows if building shared libs
# See https://stackoverflow.com/a/40743080
set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS ON)
endif()
# Threads needed for <thread> on some systems, and for <pthread.h> on Linux
find_package(Threads REQUIRED)
# Since Cmake v3.11, Crypto & SSL became optional when not specified as COMPONENTS.
if(HTTPLIB_REQUIRE_OPENSSL)
find_package(OpenSSL ${_HTTPLIB_OPENSSL_MIN_VER} COMPONENTS Crypto SSL REQUIRED)
elseif(HTTPLIB_USE_OPENSSL_IF_AVAILABLE)
find_package(OpenSSL ${_HTTPLIB_OPENSSL_MIN_VER} COMPONENTS Crypto SSL QUIET)
endif()
# Just setting this variable here for people building in-tree
if(OPENSSL_FOUND)
set(HTTPLIB_IS_USING_OPENSSL TRUE)
endif()
if(HTTPLIB_REQUIRE_ZLIB)
find_package(ZLIB REQUIRED)
elseif(HTTPLIB_USE_ZLIB_IF_AVAILABLE)
find_package(ZLIB QUIET)
endif()
# Just setting this variable here for people building in-tree
# FindZLIB doesn't have a ZLIB_FOUND variable, so check the target.
if(TARGET ZLIB::ZLIB)
set(HTTPLIB_IS_USING_ZLIB TRUE)
endif()
# Adds our cmake folder to the search path for find_package
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
if(HTTPLIB_REQUIRE_BROTLI)
find_package(Brotli COMPONENTS encoder decoder common REQUIRED)
elseif(HTTPLIB_USE_BROTLI_IF_AVAILABLE)
find_package(Brotli COMPONENTS encoder decoder common QUIET)
endif()
# Just setting this variable here for people building in-tree
if(Brotli_FOUND)
set(HTTPLIB_IS_USING_BROTLI TRUE)
endif()
# Used for default, common dirs that the end-user can change (if needed)
# like CMAKE_INSTALL_INCLUDEDIR or CMAKE_INSTALL_DATADIR
include(GNUInstallDirs)
if(HTTPLIB_COMPILE)
# Put the split script into the build dir
configure_file(split.py "${CMAKE_CURRENT_BINARY_DIR}/split.py"
COPYONLY
)
# Needs to be in the same dir as the python script
configure_file(httplib.h "${CMAKE_CURRENT_BINARY_DIR}/httplib.h"
COPYONLY
)
# Used outside of this if-else
set(_INTERFACE_OR_PUBLIC PUBLIC)
# Brings in the Python3_EXECUTABLE path we can use.
find_package(Python3 REQUIRED)
# Actually split the file
# Keeps the output in the build dir to not pollute the main dir
execute_process(COMMAND ${Python3_EXECUTABLE} "${CMAKE_CURRENT_BINARY_DIR}/split.py"
WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
ERROR_VARIABLE _httplib_split_error
)
if(_httplib_split_error)
message(FATAL_ERROR "Failed when trying to split Cpp-httplib with the Python script.\n${_httplib_split_error}")
endif()
# split.py puts output in "out"
set(_httplib_build_includedir "${CMAKE_CURRENT_BINARY_DIR}/out")
# This will automatically be either static or shared based on the value of BUILD_SHARED_LIBS
add_library(${PROJECT_NAME} "${_httplib_build_includedir}/httplib.cc")
target_sources(${PROJECT_NAME}
PUBLIC
$<BUILD_INTERFACE:${_httplib_build_includedir}/httplib.h>
$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/httplib.h>
)
else()
# This is for header-only.
set(_INTERFACE_OR_PUBLIC INTERFACE)
add_library(${PROJECT_NAME} INTERFACE)
set(_httplib_build_includedir "${CMAKE_CURRENT_SOURCE_DIR}")
endif()
# Lets you address the target with httplib::httplib
# Only useful if building in-tree, versus using it from an installation.
add_library(${PROJECT_NAME}::${PROJECT_NAME} ALIAS ${PROJECT_NAME})
# Might be missing some, but this list is somewhat comprehensive
target_compile_features(${PROJECT_NAME} ${_INTERFACE_OR_PUBLIC}
cxx_std_11
cxx_nullptr
cxx_lambdas
cxx_override
cxx_defaulted_functions
cxx_attribute_deprecated
cxx_auto_type
cxx_decltype
cxx_deleted_functions
cxx_range_for
cxx_sizeof_member
)
target_include_directories(${PROJECT_NAME} ${_INTERFACE_OR_PUBLIC}
$<BUILD_INTERFACE:${_httplib_build_includedir}>
$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
)
# Always require threads
target_link_libraries(${PROJECT_NAME} ${_INTERFACE_OR_PUBLIC}
Threads::Threads
# Needed for Windows libs on Mingw, as the pragma comment(lib, "xyz") aren't triggered.
$<$<PLATFORM_ID:Windows>:ws2_32>
$<$<PLATFORM_ID:Windows>:crypt32>
$<$<PLATFORM_ID:Windows>:cryptui>
# Can't put multiple targets in a single generator expression or it bugs out.
$<$<BOOL:${HTTPLIB_IS_USING_BROTLI}>:Brotli::common>
$<$<BOOL:${HTTPLIB_IS_USING_BROTLI}>:Brotli::encoder>
$<$<BOOL:${HTTPLIB_IS_USING_BROTLI}>:Brotli::decoder>
$<$<BOOL:${HTTPLIB_IS_USING_ZLIB}>:ZLIB::ZLIB>
$<$<BOOL:${HTTPLIB_IS_USING_OPENSSL}>:OpenSSL::SSL>
$<$<BOOL:${HTTPLIB_IS_USING_OPENSSL}>:OpenSSL::Crypto>
)
# Set the definitions to enable optional features
target_compile_definitions(${PROJECT_NAME} ${_INTERFACE_OR_PUBLIC}
$<$<BOOL:${HTTPLIB_IS_USING_BROTLI}>:CPPHTTPLIB_BROTLI_SUPPORT>
$<$<BOOL:${HTTPLIB_IS_USING_ZLIB}>:CPPHTTPLIB_ZLIB_SUPPORT>
$<$<BOOL:${HTTPLIB_IS_USING_OPENSSL}>:CPPHTTPLIB_OPENSSL_SUPPORT>
)
# Cmake's find_package search path is different based on the system
# See https://cmake.org/cmake/help/latest/command/find_package.html for the list
if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
set(_TARGET_INSTALL_CMAKEDIR "${CMAKE_INSTALL_PREFIX}/cmake/${PROJECT_NAME}")
else()
# On Non-Windows, it should be /usr/lib/cmake/<name>/<name>Config.cmake
# NOTE: This may or may not work for macOS...
set(_TARGET_INSTALL_CMAKEDIR "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}")
endif()
include(CMakePackageConfigHelpers)
# Configures the meta-file httplibConfig.cmake.in to replace variables with paths/values/etc.
configure_package_config_file("${PROJECT_NAME}Config.cmake.in"
"${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
INSTALL_DESTINATION "${_TARGET_INSTALL_CMAKEDIR}"
# Passes the includedir install path
PATH_VARS CMAKE_INSTALL_FULL_INCLUDEDIR
# There aren't any components, so don't use the macro
NO_CHECK_REQUIRED_COMPONENTS_MACRO
)
if(HTTPLIB_COMPILE)
write_basic_package_version_file("${PROJECT_NAME}ConfigVersion.cmake"
# Example: if you find_package(httplib 0.5.4)
# then anything >= 0.5 and <= 1.0 is accepted
COMPATIBILITY SameMajorVersion
)
else()
write_basic_package_version_file("${PROJECT_NAME}ConfigVersion.cmake"
# Example: if you find_package(httplib 0.5.4)
# then anything >= 0.5 and <= 1.0 is accepted
COMPATIBILITY SameMajorVersion
# Tells Cmake that it's a header-only lib
# Mildly useful for end-users :)
ARCH_INDEPENDENT
)
endif()
# Creates the export httplibTargets.cmake
# This is strictly what holds compilation requirements
# and linkage information (doesn't find deps though).
install(TARGETS ${PROJECT_NAME}
EXPORT httplibTargets
LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
)
install(FILES "${_httplib_build_includedir}/httplib.h" DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
install(FILES
"${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
"${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}ConfigVersion.cmake"
# Install it so it can be used later by the httplibConfig.cmake file.
# Put it in the same dir as our config file instead of a global path so we don't potentially stomp on other packages.
"${CMAKE_CURRENT_SOURCE_DIR}/cmake/FindBrotli.cmake"
DESTINATION ${_TARGET_INSTALL_CMAKEDIR}
)
# NOTE: This path changes depending on if it's on Windows or Linux
install(EXPORT httplibTargets
# Puts the targets into the httplib namespace
# So this makes httplib::httplib linkable after doing find_package(httplib)
NAMESPACE ${PROJECT_NAME}::
DESTINATION ${_TARGET_INSTALL_CMAKEDIR}
)