cmake_minimum_required(VERSION 3.8)
project(snmalloc C CXX)

if (NOT CMAKE_BUILD_TYPE)
  message(STATUS "No build type selected, default to: Release")
  set(CMAKE_BUILD_TYPE "Release")
endif()

include(CheckCXXCompilerFlag)
include(CheckCSourceCompiles)

option(USE_SNMALLOC_STATS "Track allocation stats" OFF)
option(SNMALLOC_CI_BUILD "Disable features not sensible for CI" OFF)
option(EXPOSE_EXTERNAL_PAGEMAP "Expose the global pagemap" OFF)
option(EXPOSE_EXTERNAL_RESERVE "Expose an interface to reserve memory using the default memory provider" OFF)
option(SNMALLOC_RUST_SUPPORT "Build static library for rust" OFF)
option(SNMALLOC_STATIC_LIBRARY   "Build static libraries" ON)
option(SNMALLOC_QEMU_WORKAROUND "Disable using madvise(DONT_NEED) to zero memory on Linux" Off)
option(SNMALLOC_OPTIMISE_FOR_CURRENT_MACHINE "Compile for current machine architecture" Off)
set(SNMALLOC_STATIC_LIBRARY_PREFIX "sn_" CACHE STRING "Static library function prefix")
option(SNMALLOC_USE_CXX17 "Build as C++17 for legacy support." OFF)

# malloc.h will error if you include it on FreeBSD, so this test must not
# unconditionally include it.
CHECK_C_SOURCE_COMPILES("
#if __has_include(<malloc_np.h>)
#include <malloc_np.h>
#if __has_include(<malloc/malloc.h>)
#include <malloc/malloc.h>
#else
#include <malloc.h>
#endif
size_t malloc_usable_size(const void* ptr) { return 0; }
int main() { return 0; }
" CONST_QUALIFIED_MALLOC_USABLE_SIZE)

# older libcs might not have getentropy, e.g. it appeared in gliobc 2.25
# so we need to fallback if we cannot compile this
CHECK_C_SOURCE_COMPILES("
#if __has_include(<unistd.h>)
#  include <unistd.h>
#endif
#if __has_include(<sys/random.h>)
#include <sys/random.h>
#endif
int main() {
  int entropy = 0;
  int res = getentropy(&entropy, sizeof(entropy));
  return res;
}
" SNMALLOC_PLATFORM_HAS_GETENTROPY)

if (NOT SNMALLOC_CI_BUILD)
  option(USE_POSIX_COMMIT_CHECKS "Instrument Posix PAL to check for access to unused blocks of memory." Off)
else ()
  # This is enabled in every bit of CI to detect errors.
  option(USE_POSIX_COMMIT_CHECKS "Instrument Posix PAL to check for access to unused blocks of memory." On)
endif ()

# Provide as macro so other projects can reuse
macro(warnings_high)
  if(MSVC)
    # Force to always compile with W4
    if(CMAKE_CXX_FLAGS MATCHES "/W[0-4]")
      string(REGEX REPLACE "/W[0-4]" "/W4" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
    else()
      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /W4")
    endif()
    # /Wv18 is required for the annotation to force inline a lambda.
    add_compile_options(/WX /wd4127 /wd4324 /wd4201)
  else()
    if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
      add_compile_options(-Wsign-conversion -Wconversion)
    endif ()
    add_compile_options(-Wall -Wextra -Werror -Wundef)
  endif()
endmacro()

macro(clangformat_targets)
  # The clang-format tool is installed under a variety of different names.  Try
  # to find a sensible one.  Only look for versions 9 explicitly - we don't
  # know whether our clang-format file will work with newer versions of the
  # tool.  It does not work with older versions as AfterCaseLabel is not supported
  # in earlier versions.
  find_program(CLANG_FORMAT NAMES
    clang-format90 clang-format-9)

  # If we've found a clang-format tool, generate a target for it, otherwise emit
  # a warning.
  if (${CLANG_FORMAT} STREQUAL "CLANG_FORMAT-NOTFOUND")
    message(WARNING "Not generating clangformat target, no clang-format tool found")
  else ()
    message(STATUS "Generating clangformat target using ${CLANG_FORMAT}")
    file(GLOB_RECURSE ALL_SOURCE_FILES CONFIGURE_DEPENDS src/*.cc src/*.h src/*.hh)
    # clangformat does not yet understand concepts well; for the moment, don't
    # ask it to format them.  See https://reviews.llvm.org/D79773
    list(FILTER ALL_SOURCE_FILES EXCLUDE REGEX "src/[^/]*/[^/]*_concept\.h$")
    add_custom_target(
      clangformat
      COMMAND ${CLANG_FORMAT}
      -i
      ${ALL_SOURCE_FILES})
  endif()
endmacro()

# Have to set this globally, as can't be set on an interface target.
if(SNMALLOC_USE_CXX17)
  set(CMAKE_CXX_STANDARD 17)
else()
  set(CMAKE_CXX_STANDARD 20)
endif()

# The main target for snmalloc
add_library(snmalloc_lib INTERFACE)
target_include_directories(snmalloc_lib INTERFACE src/)

if(NOT MSVC)
  find_package(Threads REQUIRED COMPONENTS snmalloc_lib)
  target_link_libraries(snmalloc_lib INTERFACE ${CMAKE_THREAD_LIBS_INIT})
  if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
    target_link_libraries(snmalloc_lib INTERFACE atomic)
  endif()
  if(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "x86_64")
   target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  elseif(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "amd64")
   target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  elseif(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "AMD64")
   target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  elseif(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "x86")
   target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  # XXX elseif ARM?
  endif()
endif()

if (WIN32)
  set(WIN8COMPAT FALSE CACHE BOOL "Avoid Windows 10 APIs")
  if (WIN8COMPAT)
    target_compile_definitions(snmalloc_lib INTERFACE -DWINVER=0x0603)
    message(STATUS "snmalloc: Avoiding Windows 10 APIs")
  else()
    message(STATUS "snmalloc: Using Windows 10 APIs")
    # VirtualAlloc2 is exposed by mincore.lib, not Kernel32.lib (as the
    # documentation says)
    target_link_libraries(snmalloc_lib INTERFACE mincore)
  endif()
endif()

if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
  if(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "x86_64")
    target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  elseif(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "amd64")
   target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  elseif(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "AMD64")
   target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  elseif(${CMAKE_SYSTEM_PROCESSOR} STREQUAL "x86")
   target_compile_options(snmalloc_lib INTERFACE $<$<COMPILE_LANGUAGE:CXX>:-mcx16>)
  endif()
endif ()

if(USE_SNMALLOC_STATS)
  target_compile_definitions(snmalloc_lib INTERFACE -DUSE_SNMALLOC_STATS)
endif()

if(SNMALLOC_QEMU_WORKAROUND)
  target_compile_definitions(snmalloc_lib INTERFACE -DSNMALLOC_QEMU_WORKAROUND)
endif()

if(SNMALLOC_CI_BUILD)
  target_compile_definitions(snmalloc_lib INTERFACE -DSNMALLOC_CI_BUILD)
endif()

if(USE_POSIX_COMMIT_CHECKS)
  target_compile_definitions(snmalloc_lib INTERFACE -DUSE_POSIX_COMMIT_CHECKS)
endif()

if(SNMALLOC_PLATFORM_HAS_GETENTROPY)
  target_compile_definitions(snmalloc_lib INTERFACE -DSNMALLOC_PLATFORM_HAS_GETENTROPY)
endif()

if(CONST_QUALIFIED_MALLOC_USABLE_SIZE)
  target_compile_definitions(snmalloc_lib INTERFACE -DMALLOC_USABLE_SIZE_QUALIFIER=const)
endif()


# To build with just the header library target define SNMALLOC_ONLY_HEADER_LIBRARY
# in containing Cmake file.
if(NOT DEFINED SNMALLOC_ONLY_HEADER_LIBRARY)

  warnings_high()

  if(MSVC)
    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /Zi")
    set(CMAKE_EXE_LINKER_FLAGS_RELEASE "${CMAKE_EXE_LINKER_FLAGS_RELEASE} /DEBUG")
    target_compile_definitions(snmalloc_lib INTERFACE -D_HAS_EXCEPTIONS=0)
    add_compile_options(/std:c++latest)
  else()
    add_compile_options(-fno-exceptions -fno-rtti -fomit-frame-pointer -ffunction-sections)
    # Static TLS model is unsupported on Haiku.
    # All symbols are always dynamic on haiku and -rdynamic is redundant (and unsupported).
    if (NOT CMAKE_SYSTEM_NAME MATCHES "Haiku")
	    add_compile_options(-ftls-model=initial-exec)
    	    if(SNMALLOC_CI_BUILD OR (${CMAKE_BUILD_TYPE} MATCHES "Debug"))
      		  # Get better stack traces in CI and Debug.
      		  target_link_libraries(snmalloc_lib INTERFACE "-rdynamic")
            add_compile_options(-g)
    	    endif()
    endif()

    if(SNMALLOC_OPTIMISE_FOR_CURRENT_MACHINE)
      check_cxx_compiler_flag(-march=native SUPPORT_MARCH_NATIVE)
      if (SUPPORT_MARCH_NATIVE)
        add_compile_options(-march=native)
      else()
        message(WARNING "Compiler does not support `-march=native` required by SNMALLOC_OPTIMISE_FOR_CURRENT_MACHINE")
      endif()
    endif()

    find_package(Backtrace)
    if(${Backtrace_FOUND})
      target_compile_definitions(snmalloc_lib INTERFACE -DBACKTRACE_HEADER="${Backtrace_HEADER}")
      target_link_libraries(snmalloc_lib INTERFACE ${Backtrace_LIBRARIES})
      target_include_directories(snmalloc_lib INTERFACE ${Backtrace_INCLUDE_DIRS})
    endif()

  endif()

  macro(subdirlist result curdir)
    file(GLOB children CONFIGURE_DEPENDS LIST_DIRECTORIES true RELATIVE ${curdir} ${curdir}/* )
    set(dirlist "")
    foreach(child ${children})
      if(IS_DIRECTORY ${curdir}/${child})
        list(APPEND dirlist ${child})
      endif()
    endforeach()
    set(${result} ${dirlist})
  endmacro()

  if(CMAKE_VERSION VERSION_LESS 3.14)
    set(CMAKE_REQUIRED_LIBRARIES -fuse-ld=lld)
  else()
    set(CMAKE_REQUIRED_LINK_OPTIONS -fuse-ld=lld)
  endif()
  check_cxx_source_compiles("int main() { return 1; }" LLD_WORKS)

  macro(add_shim name type)
    add_library(${name} ${type} ${ARGN})
    target_link_libraries(${name} snmalloc_lib)
    if(NOT MSVC)
      target_compile_definitions(${name} PRIVATE "SNMALLOC_EXPORT=__attribute__((visibility(\"default\")))")
    endif()
    set_target_properties(${name} PROPERTIES CXX_VISIBILITY_PRESET hidden)

    # Ensure that we do not link against C++ stdlib when compiling shims.
    if(NOT MSVC)
      set_target_properties(${name} PROPERTIES LINKER_LANGUAGE C)
      if (LLD_WORKS)
        message("Using LLD.")

        # Only include the dependencies that actually are touched.
        # Required so C++ library is not included with direct pthread access.
        target_link_libraries(${name} -Wl,--as-needed)

        # Remove all the duplicate new/malloc and free/delete definitions
        target_link_libraries(${name} -Wl,--icf=all -fuse-ld=lld)
      endif()
    endif()

  endmacro()

  if (SNMALLOC_STATIC_LIBRARY)
    add_shim(snmallocshim-static STATIC src/override/malloc.cc)
    target_compile_definitions(snmallocshim-static PRIVATE
            SNMALLOC_STATIC_LIBRARY_PREFIX=${SNMALLOC_STATIC_LIBRARY_PREFIX})
  endif ()

  if(NOT WIN32)
    set(SHARED_FILES src/override/new.cc)
    add_shim(snmallocshim SHARED ${SHARED_FILES})
    add_shim(snmallocshim-checks SHARED ${SHARED_FILES})
    target_compile_definitions(snmallocshim-checks PRIVATE CHECK_CLIENT)
  endif()

  if(SNMALLOC_RUST_SUPPORT)
    add_shim(snmallocshim-rust STATIC src/override/rust.cc)
    add_shim(snmallocshim-checks-rust STATIC src/override/rust.cc)
    target_compile_definitions(snmallocshim-checks-rust PRIVATE CHECK_CLIENT)
  endif()

  enable_testing()

  set(TESTDIR ${CMAKE_CURRENT_SOURCE_DIR}/src/test)
  subdirlist(TEST_CATEGORIES ${TESTDIR})
  list(REVERSE TEST_CATEGORIES)
  foreach(TEST_CATEGORY ${TEST_CATEGORIES})
    subdirlist(TESTS ${TESTDIR}/${TEST_CATEGORY})
    foreach(TEST ${TESTS})
      if (WIN32
          OR (CMAKE_SYSTEM_NAME STREQUAL NetBSD)
          OR (CMAKE_SYSTEM_NAME STREQUAL OpenBSD)
          OR (CMAKE_SYSTEM_NAME STREQUAL DragonFly)
          OR (CMAKE_SYSTEM_NAME STREQUAL SunOS))
        # Windows does not support aligned allocation well enough
        # for pass through.
        # NetBSD, OpenBSD and DragonFlyBSD do not support malloc*size calls.
        set(FLAVOURS fast;check)
      else()
        set(FLAVOURS fast;check) #malloc - TODO-need to add pass through back
      endif()
      foreach(FLAVOUR ${FLAVOURS})
        unset(SRC)
        aux_source_directory(${TESTDIR}/${TEST_CATEGORY}/${TEST} SRC)
        set(TESTNAME "${TEST_CATEGORY}-${TEST}-${FLAVOUR}")

        add_executable(${TESTNAME} ${SRC})

        # For all tests enable commit checking.
        target_compile_definitions(${TESTNAME} PRIVATE -DUSE_POSIX_COMMIT_CHECKS)

        if (${FLAVOUR} STREQUAL "malloc")
          target_compile_definitions(${TESTNAME} PRIVATE SNMALLOC_PASS_THROUGH)
        endif()
        if (${FLAVOUR} STREQUAL "check")
          target_compile_definitions(${TESTNAME} PRIVATE CHECK_CLIENT)
        endif()
        target_link_libraries(${TESTNAME} snmalloc_lib)
        if (${TEST} MATCHES "release-.*")
          message(STATUS "Adding test: ${TESTNAME} only for release configs")
          add_test(NAME ${TESTNAME} COMMAND ${TESTNAME} CONFIGURATIONS "Release")
        else()
          message(STATUS "Adding test: ${TESTNAME}")
          add_test(${TESTNAME} ${TESTNAME})
        endif()
        if (${TEST_CATEGORY} MATCHES "perf")
          message(STATUS "Single threaded test: ${TESTNAME}")
          set_tests_properties(${TESTNAME} PROPERTIES PROCESSORS 4)
        endif()
        if(WIN32)
          # On Windows these tests use a lot of memory as it doesn't support
          # lazy commit.
          if (${TEST} MATCHES "two_alloc_types")
            message(STATUS "Single threaded test: ${TESTNAME}")
            set_tests_properties(${TESTNAME} PROPERTIES PROCESSORS 4)
          endif()
          if (${TEST} MATCHES "fixed_region")
            message(STATUS "Single threaded test: ${TESTNAME}")
            set_tests_properties(${TESTNAME} PROPERTIES PROCESSORS 4)
          endif()
          if (${TEST} MATCHES "memory")
            message(STATUS "Single threaded test: ${TESTNAME}")
            set_tests_properties(${TESTNAME} PROPERTIES PROCESSORS 4)
          endif()
        endif()
        # if (${TEST_CATEGORY} MATCHES "func")
        #   target_compile_definitions(${TESTNAME} PRIVATE -DUSE_SNMALLOC_STATS)
        # endif ()
      endforeach()
    endforeach()
  endforeach()

  clangformat_targets()
endif()