# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
# vim: set filetype=python:
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.


@template
def check_clock_monotonic_support(lib=None, when=None):
    check_msg = "for clock_gettime(CLOCK_MONOTONIC)"
    flags = []

    if lib is not None:
        check_msg += f" in {lib}"
        flags.append(f"-l{lib}")

    check_when = building_with_gnu_compatible_cc
    if when is not None:
        check_when &= when

    return try_link(
        includes=["time.h"],
        body="struct timespec ts; clock_gettime(CLOCK_MONOTONIC, &ts);",
        check_msg=check_msg,
        flags=flags,
        when=check_when,
    )


have_raw_clock_monotonic_support = check_clock_monotonic_support()
have_rt_clock_monotonic_support = check_clock_monotonic_support(
    lib="rt", when=~have_raw_clock_monotonic_support
)

set_define(
    "HAVE_CLOCK_MONOTONIC",
    have_raw_clock_monotonic_support | have_rt_clock_monotonic_support,
)
set_config(
    "HAVE_CLOCK_MONOTONIC",
    have_raw_clock_monotonic_support | have_rt_clock_monotonic_support,
)

set_config("REALTIME_LIBS", ["-lrt"], when=have_rt_clock_monotonic_support)


have_res_ninit = try_link(
    includes=["sys/types.h", "netinet/in.h", "arpa/nameser.h", "resolv.h"],
    body="int foo = res_ninit(&_res);",
    check_msg="for res_ninit()",
    flags=depends(when=building_linux)(["-D_BSD_SOURCE=1"]),
    when=building_with_gnu_compatible_cc & ~target_is_netbsd & ~target_is_openbsd,
)

set_define("HAVE_RES_NINIT", have_res_ninit)

# We don't want to link with libdl even if it's present on OS X, since
# it's not used and not part of the default installation.
# We don't want to link against libm or libpthread on Darwin since
# they both are just symlinks to libSystem and explicitly linking
# against libSystem causes issues when debugging (see bug 299601).
with only_when(building_with_gnu_compatible_cc):
    dladdr_check = check_symbol_in_libs([None, "dl"], symbol="dladdr")
    set_define(
        "HAVE_DLADDR", depends(dladdr_check)(lambda check: "1" if check.found else "0")
    )

    with only_when(~target_is_darwin):
        check_header("dlfcn.h")
        dlopen_check = check_symbol_in_libs(["dl", None], symbol="dlopen")
        set_config(
            "DL_LIBS", ["-ldl"], when=depends(dlopen_check)(lambda check: check.lib)
        )


set_config(
    "C_R_LIBS",
    ["-lc_r"],
    when=check_symbol_in_lib(
        "c_r", symbol="gethostbyname_r", when=building_with_gnu_compatible_cc
    ),
)
set_config(
    "SOCKET_LIBS",
    ["-lsocket"],
    when=check_symbol_in_lib(
        "socket", symbol="socket", when=building_with_gnu_compatible_cc
    ),
)

moz_use_pthreads = (
    target_is_darwin
    | check_symbol_in_libs(
        [None, "pthread"],
        symbol="pthread_create",
        when=building_with_gnu_compatible_cc & ~target_is_darwin,
    ).found
)

with only_when(moz_use_pthreads):
    check_header("pthread.h")

    pthread_flags = dependable(lambda: namespace(cflags=[]))

    (have_pthread_cflag,) = check_and_add_flags(
        "-pthread",
        pthread_flags,
        ["-Werror", "-pthread"],
        compiler=c_compiler,
    )

    @depends(pthread_flags, compilation_flags)
    def add_pthread_linker_flags(pthread_flags, compilation_flags):
        # Handle compilation flags update
        compilation_flags.cflags.extend(pthread_flags.cflags)
        compilation_flags.cxxflags.extend(pthread_flags.cflags)

    set_config("MOZ_USE_PTHREADS", True)


with only_when(building_with_gnu_compatible_cc):

    @template
    def check_std_atomic_requirements(flag=None, when=None):
        return try_link(
            includes=["cstdint", "atomic"],
            body="std::atomic<uint64_t> foo; foo = 1;",
            flags=flag or [],
            when=when,
        )

    is_libatomic_optional = check_std_atomic_requirements()
    is_libatomic_required = check_std_atomic_requirements(
        flag=["-latomic"], when=~is_libatomic_optional
    )

    @depends(is_libatomic_optional, is_libatomic_required)
    @checking("whether 64-bits std::atomic requires -latomic")
    def checking_needs_libatomic(is_libatomic_optional, is_libatomic_required):
        if is_libatomic_optional:
            return False
        if is_libatomic_required:
            return True
        return "do not know; assuming no"

    set_config(
        "LIBATOMIC_LIBS",
        ["-latomic"],
        when=depends(checking_needs_libatomic)(lambda c: c is True),
    )