CMakeLists.txt

# Copyright (c) the JPEG XL Project Authors.
#
# Use of this source code is governed by a BSD-style
# license that can be found in the LICENSE file or at
# https://developers.google.com/open-source/licenses/bsd

# Ubuntu bionic ships with cmake 3.10.
cmake_minimum_required(VERSION 3.10)
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")

# Honor VISIBILITY_INLINES_HIDDEN on all types of targets.
if(POLICY CMP0063)
  cmake_policy(SET CMP0063 NEW)
endif()
# Pass CMAKE_EXE_LINKER_FLAGS to CC and CXX compilers when testing if they work.
if(POLICY CMP0065)
  cmake_policy(SET CMP0065 NEW)
endif()

# Set PIE flags for POSITION_INDEPENDENT_CODE targets, added in 3.14.
if(POLICY CMP0083)
  cmake_policy(SET CMP0083 NEW)
endif()

project(LIBJXL LANGUAGES C CXX)

include(CheckCXXSourceCompiles)
check_cxx_source_compiles(
   "int main() {
      #if !defined(__EMSCRIPTEN__)
      static_assert(false, \"__EMSCRIPTEN__ is not defined\");
      #endif
      return 0;
    }"
  JPEGXL_EMSCRIPTEN
)

message(STATUS "CMAKE_SYSTEM_PROCESSOR is ${CMAKE_SYSTEM_PROCESSOR}")
include(CheckCXXCompilerFlag)
check_cxx_compiler_flag("-fsanitize=fuzzer-no-link" CXX_FUZZERS_SUPPORTED)
check_cxx_compiler_flag("-Xclang -mconstructor-aliases" CXX_CONSTRUCTOR_ALIASES_SUPPORTED)
check_cxx_compiler_flag("-fmacro-prefix-map=OLD=NEW" CXX_MACRO_PREFIX_MAP)
check_cxx_compiler_flag("-fno-rtti" CXX_NO_RTTI_SUPPORTED)

# Enabled PIE binaries by default if supported.
include(CheckPIESupported OPTIONAL RESULT_VARIABLE CHECK_PIE_SUPPORTED)
if(CHECK_PIE_SUPPORTED)
  check_pie_supported(LANGUAGES CXX)
  if(CMAKE_CXX_LINK_PIE_SUPPORTED)
    set(CMAKE_POSITION_INDEPENDENT_CODE TRUE)
  endif()
endif()

### Project build options:
if(CXX_FUZZERS_SUPPORTED)
  # Enabled by default except on arm64, Windows and Apple builds.
  set(ENABLE_FUZZERS_DEFAULT true)
endif()
find_package(PkgConfig)
if(NOT APPLE AND NOT WIN32 AND NOT HAIKU AND CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64")
  pkg_check_modules(TCMallocMinimalVersionCheck QUIET IMPORTED_TARGET
      libtcmalloc_minimal)
  if(TCMallocMinimalVersionCheck_FOUND AND
     NOT TCMallocMinimalVersionCheck_VERSION VERSION_EQUAL 2.8.0)
    # Enabled by default except on Windows and Apple builds for
    # tcmalloc != 2.8.0. tcmalloc 2.8.1 already has a fix for this issue.
    set(ENABLE_TCMALLOC_DEFAULT true)
  else()
    message(STATUS
        "tcmalloc version ${TCMallocMinimalVersionCheck_VERSION} -- "
        "tcmalloc 2.8.0 disabled due to "
        "https://github.com/gperftools/gperftools/issues/1204")
  endif()
endif()

set(WARNINGS_AS_ERRORS_DEFAULT false)

if((SANITIZER STREQUAL "msan") OR JPEGXL_EMSCRIPTEN)
  set(BUNDLE_LIBPNG_DEFAULT YES)
else()
  set(BUNDLE_LIBPNG_DEFAULT NO)
endif()

# Standard cmake naming for building shared libraries.
get_property(SHARED_LIBS_SUPPORTED GLOBAL PROPERTY TARGET_SUPPORTS_SHARED_LIBS)
option(BUILD_SHARED_LIBS "Build shared libraries instead of static ones" ${SHARED_LIBS_SUPPORTED})

set(JPEGXL_ENABLE_FUZZERS ${ENABLE_FUZZERS_DEFAULT} CACHE BOOL
    "Build JPEGXL fuzzer targets.")
set(JPEGXL_ENABLE_DEVTOOLS false CACHE BOOL
    "Build JPEGXL developer tools.")
set(JPEGXL_ENABLE_TOOLS true CACHE BOOL
    "Build JPEGXL user tools: cjxl and djxl.")
set(JPEGXL_ENABLE_BENCHMARK true CACHE BOOL
    "Build JPEGXL benchmark tools.")
set(JPEGXL_ENABLE_EXAMPLES true CACHE BOOL
    "Build JPEGXL library usage examples.")
set(JPEGXL_BUNDLE_LIBPNG ${BUNDLE_LIBPNG_DEFAULT} CACHE BOOL
    "Build libpng from source and link it statically.")
set(JPEGXL_ENABLE_JNI true CACHE BOOL
    "Build JPEGXL JNI Java wrapper, if Java dependencies are installed.")
set(JPEGXL_ENABLE_SJPEG true CACHE BOOL
    "Build JPEGXL with support for encoding with sjpeg.")
set(JPEGXL_ENABLE_OPENEXR true CACHE BOOL
    "Build JPEGXL with support for OpenEXR if available.")
set(JPEGXL_ENABLE_SKCMS true CACHE BOOL
    "Build with skcms instead of lcms2.")
set(JPEGXL_BUNDLE_SKCMS true CACHE BOOL
    "When building with skcms, bundle it into libjxl.a.")
set(JPEGXL_ENABLE_VIEWERS false CACHE BOOL
    "Build JPEGXL viewer tools for evaluation.")
set(JPEGXL_ENABLE_TCMALLOC ${ENABLE_TCMALLOC_DEFAULT} CACHE BOOL
    "Build JPEGXL using gperftools (tcmalloc) allocator.")
set(JPEGXL_ENABLE_PLUGINS false CACHE BOOL
    "Build third-party plugins to support JPEG XL in other applications.")
set(JPEGXL_ENABLE_COVERAGE false CACHE BOOL
    "Enable code coverage tracking for libjxl. This also enables debug and disables optimizations.")
set(JPEGXL_ENABLE_PROFILER false CACHE BOOL
    "Builds in support for profiling (printed by tools if extra flags given")
set(JPEGXL_ENABLE_TRANSCODE_JPEG true CACHE BOOL
    "Builds in support for decoding transcoded JXL files back to JPEG,\
 disabling it makes the decoder reject JXL_DEC_JPEG_RECONSTRUCTION events,\
 (default enabled)")
set(JPEGXL_STATIC false CACHE BOOL
    "Build tools as static binaries.")
set(JPEGXL_WARNINGS_AS_ERRORS ${WARNINGS_AS_ERRORS_DEFAULT} CACHE BOOL
    "Treat warnings as errors during compilation.")
set(JPEGXL_DEP_LICENSE_DIR "" CACHE STRING
    "Directory where to search for system dependencies \"copyright\" files.")
set(JPEGXL_FORCE_NEON false CACHE BOOL
    "Set flags to enable NEON in arm if not enabled by your toolchain.")


# Force system dependencies.
set(JPEGXL_FORCE_SYSTEM_BROTLI false CACHE BOOL
    "Force using system installed brotli instead of third_party/brotli source.")
set(JPEGXL_FORCE_SYSTEM_GTEST false CACHE BOOL
    "Force using system installed googletest (gtest/gmock) instead of third_party/googletest source.")
set(JPEGXL_FORCE_SYSTEM_LCMS2 false CACHE BOOL
    "Force using system installed lcms2 instead of third_party/lcms source.")
set(JPEGXL_FORCE_SYSTEM_HWY false CACHE BOOL
    "Force using system installed highway (libhwy-dev) instead of third_party/highway source.")

# Check minimum compiler versions. Older compilers are not supported and fail
# with hard to understand errors.
if (NOT CMAKE_C_COMPILER_ID STREQUAL CMAKE_CXX_COMPILER_ID)
  message(FATAL_ERROR "Different C/C++ compilers set: "
          "${CMAKE_C_COMPILER_ID} vs ${CMAKE_CXX_COMPILER_ID}")
endif()
if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
  # Android NDK's toolchain.cmake fakes the clang version in
  # CMAKE_CXX_COMPILER_VERSION with an incorrect number, so ignore this.
  if (NOT CMAKE_ANDROID_NDK_TOOLCHAIN_VERSION MATCHES "clang"
      AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5)
    message(FATAL_ERROR
      "Minimum Clang version required is Clang 5, please update.")
  endif()
elseif (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7)
    message(FATAL_ERROR
      "Minimum GCC version required is 7, please update.")
  endif()
endif()

message(STATUS
    "Compiled IDs C:${CMAKE_C_COMPILER_ID}, C++:${CMAKE_CXX_COMPILER_ID}")

# CMAKE_EXPORT_COMPILE_COMMANDS is used to generate the compilation database
# used by clang-tidy.
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

if(JPEGXL_STATIC)
  set(BUILD_SHARED_LIBS 0)
  # Clang developers say that in case to use "static" we have to build stdlib
  # ourselves; for real use case we don't care about stdlib, as it is "granted",
  # so just linking all other libraries is fine.
  if (NOT MSVC AND NOT APPLE)
    set(CMAKE_FIND_LIBRARY_SUFFIXES .a)
    set(CMAKE_EXE_LINKER_FLAGS
        "${CMAKE_EXE_LINKER_FLAGS} -static -static-libgcc -static-libstdc++")
  endif()
endif()  # JPEGXL_STATIC

# Threads
set(THREADS_PREFER_PTHREAD_FLAG YES)
find_package(Threads REQUIRED)

# These settings are important to drive check_cxx_source_compiles
# See CMP0067 (min cmake version is 3.10 anyway)
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_EXTENSIONS OFF)
set(CMAKE_CXX_STANDARD_REQUIRED YES)

# Atomics
find_package(Atomics REQUIRED)

if(JPEGXL_STATIC)
  if (MINGW)
    # In MINGW libstdc++ uses pthreads directly. When building statically a
    # program (regardless of whether the source code uses pthread or not) the
    # toolchain will add stdc++ and pthread to the linking step but stdc++ will
    # be linked statically while pthread will be linked dynamically.
    # To avoid this and have pthread statically linked with need to pass it in
    # the command line with "-Wl,-Bstatic -lpthread -Wl,-Bdynamic" but the
    # linker will discard it if not used by anything else up to that point in
    # the linker command line. If the program or any dependency don't use
    # pthread directly -lpthread is discarded and libstdc++ (added by the
    # toolchain later) will then use the dynamic version. For this we also need
    # to pass -lstdc++ explicitly before -lpthread. For pure C programs -lstdc++
    # will be discarded anyway.
    # This adds these flags as dependencies for *all* targets. Adding this to
    # CMAKE_EXE_LINKER_FLAGS instead would cause them to be included before any
    # object files and therefore discarded. This should be set in the
    # INTERFACE_LINK_LIBRARIES of Threads::Threads but some third_part targets
    # don't depend on it.
    link_libraries(-Wl,-Bstatic -lstdc++ -lpthread -Wl,-Bdynamic)
  elseif(CMAKE_USE_PTHREADS_INIT)
    # "whole-archive" is not supported on OSX.
    if (NOT APPLE)
      # Set pthreads as a whole-archive, otherwise weak symbols in the static
      # libraries will discard pthreads symbols leading to segmentation fault at
      # runtime.
      message(STATUS "Using -lpthread as --whole-archive")
      set_target_properties(Threads::Threads PROPERTIES
        INTERFACE_LINK_LIBRARIES
            "-Wl,--whole-archive;-lpthread;-Wl,--no-whole-archive")
    endif()
  endif()
endif()  # JPEGXL_STATIC

if (JPEGXL_EMSCRIPTEN)
  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -pthread")
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pthread")
  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pthread")
endif()

if (CXX_MACRO_PREFIX_MAP)
  add_compile_options(-fmacro-prefix-map=${CMAKE_CURRENT_SOURCE_DIR}=.)
endif()

if (CXX_NO_RTTI_SUPPORTED)
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
endif()

if (MSVC)
# TODO(janwas): add flags
else ()

# Global compiler flags for all targets here and in subdirectories.
add_definitions(
  # Avoid changing the binary based on the current time and date.
  -D__DATE__="redacted"
  -D__TIMESTAMP__="redacted"
  -D__TIME__="redacted"
)

# Avoid log spam from fopen etc.
if(MSVC)
  add_definitions(-D_CRT_SECURE_NO_WARNINGS)
endif()

# In CMake before 3.12 it is problematic to pass repeated flags like -Xclang.
# For this reason we place them in CMAKE_CXX_FLAGS instead.
# See https://gitlab.kitware.com/cmake/cmake/issues/15826

# Machine flags.
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -funwind-tables")
if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Xclang -mrelax-all")
endif()
if (CXX_CONSTRUCTOR_ALIASES_SUPPORTED)
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Xclang -mconstructor-aliases")
endif()

if(WIN32)
# Not supported by clang-cl, but frame pointers are default on Windows
else()
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-omit-frame-pointer")
endif()

# CPU flags - remove once we have NEON dynamic dispatch

# TODO(janwas): this also matches M1, but only ARMv7 is intended/needed.
if(CMAKE_SYSTEM_PROCESSOR MATCHES "arm")
if(JPEGXL_FORCE_NEON)
# GCC requires these flags, otherwise __ARM_NEON is undefined.
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} \
   -mfpu=neon-vfpv4 -mfloat-abi=hard")
endif()
endif()

# Force build with optimizations in release mode.
set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O2")

add_compile_options(
  # Ignore this to allow redefining __DATE__ and others.
  -Wno-builtin-macro-redefined

  # Global warning settings.
  -Wall
)

if (JPEGXL_WARNINGS_AS_ERRORS)
add_compile_options(-Werror)
endif ()
endif ()  # !MSVC

include(GNUInstallDirs)

# Separately build/configure testing frameworks and other third_party libraries
# to allow disabling tests in those libraries.
include(third_party/testing.cmake)
add_subdirectory(third_party)
# Copy the JXL license file to the output build directory.
configure_file("${CMAKE_CURRENT_SOURCE_DIR}/LICENSE"
               ${PROJECT_BINARY_DIR}/LICENSE.jpeg-xl COPYONLY)

# Enable tests regardless of where they are defined.
enable_testing()
include(CTest)
# Specify default location of `testdata`:
if(NOT DEFINED JPEGXL_TEST_DATA_PATH)
  set(JPEGXL_TEST_DATA_PATH "${PROJECT_SOURCE_DIR}/testdata")
endif()

if(BUILD_TESTING)
# Script to run tests over the source code in bash.
find_program (BASH_PROGRAM bash)
if(BASH_PROGRAM)
  add_test(
    NAME bash_test
    COMMAND ${BASH_PROGRAM} ${CMAKE_CURRENT_SOURCE_DIR}/bash_test.sh)
endif()
endif() # BUILD_TESTING

# Encoder only sources
add_subdirectory(encoder)