project(musl C ASM )
cmake_minimum_required(VERSION 3.0)

if(NOT DEFINED MUSL_ARCH)
        set(MUSL_ARCH ${CMAKE_SYSTEM_PROCESSOR} )
endif()

if(NOT DEFINED MUSL_SYSLIBDIR)
        set(MUSL_SYSLIBDIR "$ENV{DESTDIR}/lib" )
endif()

set(CMAKE_C_FLAGS
        "${CMAKE_C_FLAGS} \
        -fPIC \
        -nodefaultlibs \
        -fexceptions\
        -Wall \
        -std=c99 \
        -isysroot${CMAKE_SOURCE_DIR}/include \
        -D_XOPEN_SOURCE=700\
        -Os\
        -pipe\
        -ffreestanding"
)

set(CMAKE_C_OUTPUT_EXTENSION_REPLACE 1)

include_directories(
    "${CMAKE_SOURCE_DIR}/arch/generic/"
    "${CMAKE_SOURCE_DIR}/arch/${MUSL_ARCH}"
    "${CMAKE_BINARY_DIR}"
    "${CMAKE_BINARY_DIR}/arch"
)

file(MAKE_DIRECTORY "${CMAKE_BINARY_DIR}/arch/bits/")

add_custom_target(alltypes
    COMMAND
        sed -f "${CMAKE_SOURCE_DIR}/tools/mkalltypes.sed" "${CMAKE_SOURCE_DIR}/arch/${MUSL_ARCH}/bits/alltypes.h.in" "${CMAKE_SOURCE_DIR}/include/alltypes.h.in" >  "${CMAKE_CURRENT_BINARY_DIR}/arch/bits/alltypes.h"
)

add_custom_target(syscall
    COMMAND
        sed -n -e s/__NR_/SYS_/p < "${CMAKE_SOURCE_DIR}/arch/${MUSL_ARCH}/bits/syscall.h.in" >  "${CMAKE_CURRENT_BINARY_DIR}/arch/bits/syscall.h"
)

execute_process(
    COMMAND
        sh tools/version.sh
    COMMAND_ECHO
        STDOUT
    RESULT_VARIABLE
        version
    WORKING_DIRECTORY
        ${CMAKE_SOURCE_DIR}
)

file(WRITE "${CMAKE_BINARY_DIR}/version.h" "#define VERSION \"${version}\"")

if(EXISTS "${CMAKE_SOURCE_DIR}/src/thread/${MUSL_ARCH}")
    list(APPEND muslSrcs
       "${CMAKE_SOURCE_DIR}/src/thread/${MUSL_ARCH}/syscall_cp.s"
    )
    file(GLOB thread_arch_src
        "${CMAKE_SOURCE_DIR}/src/thread/${MUSL_ARCH}/*.s"
    )
endif()

file(GLOB crtSrcs
    "${CMAKE_SOURCE_DIR}/crt/*.c"
)

file(GLOB crtArchSrcs
    "${CMAKE_SOURCE_DIR}/crt/${MUSL_ARCH}/*.s"
)

file( GLOB muslSrcs
    "${CMAKE_SOURCE_DIR}/ldso/*.c"
    "${CMAKE_SOURCE_DIR}/src/*/*.c"
    "${CMAKE_SOURCE_DIR}/src/malloc/mallocng/*.c"
)

file(GLOB muslArchSrcs
    "${CMAKE_SOURCE_DIR}/src/*/${MUSL_ARCH}/*.c"
    "${CMAKE_SOURCE_DIR}/src/*/${MUSL_ARCH}/*.s"
)

list(FILTER muslSrcs EXCLUDE REGEX "${CMAKE_SOURCE_DIR}/src/malloc/oldmalloc*")

macro(replace_list_item LIST OLD_VALUE NEW_VALUE)
    list(FIND ${LIST} ${OLD_VALUE} OLD_VALUE_INDEX)
    if(OLD_VALUE_INDEX GREATER_EQUAL 0)
        list(REMOVE_AT ${LIST} ${OLD_VALUE_INDEX})
        list(INSERT ${LIST} ${OLD_VALUE_INDEX} ${NEW_VALUE})
    endif()
endmacro()

foreach(srcf ${muslSrcs})
    get_filename_component(srcfname ${srcf} NAME_WLE)
    foreach(acsrcf ${muslArchSrcs})
        get_filename_component(acsrcfname ${acsrcf} NAME_WLE)
        if(${srcfname} STREQUAL ${acsrcfname})
            replace_list_item(muslSrcs ${srcf} ${acsrcf})
        endif()
    endforeach()
endforeach()

file (GLOB arch_mathsrc
    "${CMAKE_SOURCE_DIR}/src/math/${MUSL_ARCH}/*.c"
    "${CMAKE_SOURCE_DIR}/src/math/${MUSL_ARCH}/*.s"
)

file (GLOB mathsrc
    "${CMAKE_SOURCE_DIR}/src/math/*.c"
)

foreach(arfp ${arch_mathsrc})
    get_filename_component(arfname ${arfp} NAME_WLE)
    foreach(fp ${mathsrc})
        get_filename_component(fpfname ${fp} NAME_WLE)
        if(${fpfname} STREQUAL ${arfname})
            replace_list_item(mathsrc ${fp} ${arfp})
        endif()
    endforeach()
endforeach()

add_library( crt OBJECT
    ${crtSrcs}
)

target_include_directories( crt PRIVATE
    "${CMAKE_SOURCE_DIR}/src/internal"
    "${CMAKE_SOURCE_DIR}/src/include"
    "${CMAKE_SOURCE_DIR}/include"
    "${CMAKE_SOURCE_DIR}/src/internal/dynlink.h"
    "${CMAKE_SOURCE_DIR}/arch/${MUSL_ARCH}/reloc.h"
    "${CMAKE_SOURCE_DIR}/arch/${MUSL_ARCH}/crt_arch.h"
)

target_compile_definitions(crt PRIVATE
    "-DCRT"
)

list(APPEND NOSSP_OBJS ${muslSrcs})

list(FILTER NOSSP_OBJS EXCLUDE REGEX "/*/__libc_start_main.c|/*/__init_tls.c|/*/__stack_chk_fail.c|/*/__set_thread_area.c|/*/memset.c|/*/memcpy.c")

add_library(muslobj OBJECT
    ${muslSrcs}
)

add_dependencies(muslobj syscall alltypes)

target_include_directories(muslobj
PRIVATE
    "${CMAKE_SOURCE_DIR}/src/include"
    "${CMAKE_SOURCE_DIR}/src/internal"
    "${CMAKE_SOURCE_DIR}/src/internal/stdio_impl.h"
    "${CMAKE_SOURCE_DIR}/src/internal/pthread_impl.h"
    "${CMAKE_SOURCE_DIR}/src/internal/locale_impl.h"
    "${CMAKE_SOURCE_DIR}/src/internal/libc.h"
    "${CMAKE_BINARY_DIR}/arch"
PUBLIC
    "${CMAKE_SOURCE_DIR}/include"
)

#shared build
add_library(musl SHARED
    $<TARGET_OBJECTS:muslobj>
)

SET_SOURCE_FILES_PROPERTIES(
  "${CMAKE_SOURCE_DIR}/crt/crt1.c"  PROPERTIES GENERATED TRUE
)

target_include_directories(musl PUBLIC
     "${CMAKE_SOURCE_DIR}/include"
)

target_link_options(musl PUBLIC
    "-Wl,-e,_dlstart"
)

target_link_libraries(musl PRIVATE
  "gcc"
)

set_target_properties(musl PROPERTIES OUTPUT_NAME c)

add_dependencies(musl muslobj)

#statiuc build
add_library(musl-static STATIC
    $<TARGET_OBJECTS:muslobj>
)



target_include_directories(musl-static
PRIVATE
    "${CMAKE_SOURCE_DIR}/src/include"
    "${CMAKE_SOURCE_DIR}/src/internal"
PUBLIC
    "${CMAKE_SOURCE_DIR}/include"
)

set_target_properties(musl-static PROPERTIES OUTPUT_NAME c)

add_dependencies(musl-static muslobj)

target_link_libraries(musl PRIVATE
  "gcc"
)

file(CREATE_LINK ${MUSL_SYSLIBDIR}/libc.so ${CMAKE_BINARY_DIR}/ld-musl-${MUSL_ARCH}.so.1 SYMBOLIC)

add_dependencies(musl-static syscall alltypes)

file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/libm.so SYMBOLIC)
file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/librt.so SYMBOLIC)
file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/libpthread.so SYMBOLIC)
file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/libcrypt.so SYMBOLIC)
file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/libutil.so SYMBOLIC)
file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/libxnet.so SYMBOLIC)
file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/libresolv.so SYMBOLIC)
file(CREATE_LINK libc.so ${CMAKE_BINARY_DIR}/libdl.so SYMBOLIC)

install(
FILES
    "${CMAKE_BINARY_DIR}/libm.so"
    "${CMAKE_BINARY_DIR}/librt.so"
    "${CMAKE_BINARY_DIR}/libpthread.so"
    "${CMAKE_BINARY_DIR}/libcrypt.so"
    "${CMAKE_BINARY_DIR}/libutil.so"
    "${CMAKE_BINARY_DIR}/libxnet.so"
    "${CMAKE_BINARY_DIR}/libresolv.so"
    "${CMAKE_BINARY_DIR}/libdl.so"
DESTINATION lib
COMPONENT lib
)

install(
TARGETS
    musl
    musl-static
DESTINATION
    lib
)

install(
FILES
    ${CMAKE_BINARY_DIR}/ld-musl-${MUSL_ARCH}.so.1
DESTINATION
    ${MUSL_SYSLIBDIR}
)

install(
FILES
    "${CMAKE_BINARY_DIR}/arch/bits/syscall.h"
    "${CMAKE_BINARY_DIR}/arch/bits/alltypes.h"
DESTINATION
    include/bits
)

install(
DIRECTORY
    ${CMAKE_SOURCE_DIR}/include/
    ${CMAKE_SOURCE_DIR}/arch/generic/
    ${CMAKE_SOURCE_DIR}/arch/${MUSL_ARCH}/
DESTINATION
    include
)

install(
    FILES
    $<TARGET_OBJECTS:crt>
    DESTINATION lib
)