# This file contains the functions common to glibc and eglibc

# Build and install headers and start files
do_libc_start_files() {
    local src_dir="${CT_SRC_DIR}/${CT_LIBC}-${CT_LIBC_VERSION}"

    CT_DoStep INFO "Installing C library headers & start files"

    mkdir -p "${CT_BUILD_DIR}/build-libc-startfiles"
    cd "${CT_BUILD_DIR}/build-libc-startfiles"

    CT_DoLog EXTRA "Configuring C library"

    case "${CT_LIBC}" in
        eglibc)
            if [ "${CT_EGLIBC_CUSTOM_CONFIG}" = "y" ]; then
                CT_DoExecLog ALL cp "${CT_CONFIG_DIR}/eglibc.config" option-groups.config
            fi
            ;;
    esac

    cross_cc=$(CT_Which "${CT_TARGET}-gcc")
    cross_cxx=$(CT_Which "${CT_TARGET}-g++")
    cross_ar=$(CT_Which "${CT_TARGET}-ar")
    cross_ranlib=$(CT_Which "${CT_TARGET}-ranlib")

    CT_DoLog DEBUG "Using gcc for target: '${cross_cc}'"
    CT_DoLog DEBUG "Using g++ for target: '${cross_cxx}'"
    CT_DoLog DEBUG "Using ar for target: '${cross_ar}'"
    CT_DoLog DEBUG "Using ranlib for target: '${cross_ranlib}'"

    touch config.cache
    if [ "${CT_LIBC_GLIBC_FORCE_UNWIND}" = "y" ]; then
        echo "libc_cv_forced_unwind=yes" >>config.cache
        echo "libc_cv_c_cleanup=yes" >>config.cache
    fi

    # Pre-seed the configparms file with values from the config option
    printf "${CT_LIBC_GLIBC_CONFIGPARMS}\n" > configparms

    CT_DoExecLog CFG                                    \
    BUILD_CC="${CT_BUILD}-gcc"                          \
    CC=${cross_cc}                                      \
    CXX=${cross_cxx}                                    \
    AR=${cross_ar}                                      \
    RANLIB=${cross_ranlib}                              \
    "${src_dir}/configure"                              \
        --prefix=/usr                                   \
        --with-headers="${CT_HEADERS_DIR}"              \
        --build="${CT_BUILD}"                           \
        --host="${CT_TARGET}"                           \
        --cache-file="$(pwd)/config.cache"              \
        --disable-profile                               \
        --without-gd                                    \
        --without-cvs                                   \
        --enable-add-ons

    CT_DoLog EXTRA "Installing C library headers"

    # use the 'install-headers' makefile target to install the
    # headers
    CT_DoExecLog ALL make ${JOBSFLAGS}              \
                     install_root=${CT_SYSROOT_DIR} \
                     install-bootstrap-headers=yes  \
                     install-headers

    # For glibc, a few headers need to be manually installed
    if [ "${CT_LIBC}" = "glibc" ]; then
        # Two headers -- stubs.h and features.h -- aren't installed by install-headers,
        # so do them by hand.  We can tolerate an empty stubs.h for the moment.
        # See e.g. http://gcc.gnu.org/ml/gcc/2002-01/msg00900.html
        mkdir -p "${CT_HEADERS_DIR}/gnu"
        CT_DoExecLog ALL touch "${CT_HEADERS_DIR}/gnu/stubs.h"
        CT_DoExecLog ALL cp -v "${CT_SRC_DIR}/glibc-${CT_LIBC_VERSION}/include/features.h"  \
                               "${CT_HEADERS_DIR}/features.h"

        # Building the bootstrap gcc requires either setting inhibit_libc, or
        # having a copy of stdio_lim.h... see
        # http://sources.redhat.com/ml/libc-alpha/2003-11/msg00045.html
        CT_DoExecLog ALL cp -v bits/stdio_lim.h "${CT_HEADERS_DIR}/bits/stdio_lim.h"

        # Following error building gcc-4.0.0's gcj:
        #  error: bits/syscall.h: No such file or directory
        # solved by following copy; see http://sourceware.org/ml/crossgcc/2005-05/msg00168.html
        # but it breaks arm, see http://sourceware.org/ml/crossgcc/2006-01/msg00091.html
        case "${CT_ARCH}" in
            arm)    ;;
            *)  CT_DoExecLog ALL cp -v "misc/syscall-list.h"            \
                                       "${CT_HEADERS_DIR}/bits/syscall.h"
                ;;
        esac
    fi

    if [ "${CT_THREADS}" = "nptl" ]; then
        CT_DoLog EXTRA "Installing C library start files"

        # there are a few object files needed to link shared libraries,
        # which we build and install by hand
        CT_DoExecLog ALL mkdir -p "${CT_SYSROOT_DIR}/usr/lib"
        CT_DoExecLog ALL make ${JOBSFLAGS} csu/subdir_lib
        CT_DoExecLog ALL cp csu/crt1.o csu/crti.o csu/crtn.o \
                            "${CT_SYSROOT_DIR}/usr/lib"

        # Finally, 'libgcc_s.so' requires a 'libc.so' to link against.
        # However, since we will never actually execute its code,
        # it doesn't matter what it contains.  So, treating '/dev/null'
        # as a C source file, we produce a dummy 'libc.so' in one step
        CT_DoExecLog ALL "${cross_cc}" -nostdlib        \
                                       -nostartfiles    \
                                       -shared          \
                                       -x c /dev/null   \
                                       -o "${CT_SYSROOT_DIR}/usr/lib/libc.so"
    fi # threads == nptl

    CT_EndStep
}

# This function builds and install the full C library
do_libc() {
    local src_dir="${CT_SRC_DIR}/${CT_LIBC}-${CT_LIBC_VERSION}"
    local extra_cc_args
    local -a extra_config
    local -a extra_make_args
    local glibc_cflags

    CT_DoStep INFO "Installing C library"

    mkdir -p "${CT_BUILD_DIR}/build-libc"
    cd "${CT_BUILD_DIR}/build-libc"

    CT_DoLog EXTRA "Configuring C library"

    case "${CT_LIBC}" in
        eglibc)
            if [ "${CT_EGLIBC_CUSTOM_CONFIG}" = "y" ]; then
                CT_DoExecLog ALL cp "${CT_CONFIG_DIR}/eglibc.config" option-groups.config
            fi
            if [ "${CT_EGLIBC_OPT_SIZE}" = "y" ]; then
                OPTIMIZE=-Os
            else
                OPTIMIZE=-O2
            fi
            ;;
        glibc)
            # glibc can't be built without -O2 (reference needed!)
            OPTIMIZE=-O2
            # Also, if those two are missing, iconv build breaks
            extra_config+=( --disable-debug --disable-sanity-checks )
            ;;
    esac

    # Add some default glibc config options if not given by user.
    # We don't need to be conditional on wether the user did set different
    # values, as they CT_LIBC_GLIBC_EXTRA_CONFIG is passed after extra_config

    extra_config+=("$(do_libc_min_kernel_config)")

    case "${CT_THREADS}" in
        nptl)           extra_config+=("--with-__thread" "--with-tls");;
        linuxthreads)   extra_config+=("--with-__thread" "--without-tls" "--without-nptl");;
        none)           extra_config+=("--without-__thread" "--without-nptl")
                        case "${CT_LIBC_GLIBC_EXTRA_CONFIG}" in
                            *-tls*) ;;
                            *) extra_config+=("--without-tls");;
                        esac
                        ;;
    esac

    case "${CT_SHARED_LIBS}" in
        y) extra_config+=("--enable-shared");;
        *) extra_config+=("--disable-shared");;
    esac

    case "${CT_ARCH_FLOAT_HW},${CT_ARCH_FLOAT_SW}" in
        y,) extra_config+=("--with-fp");;
        ,y) extra_config+=("--without-fp");;
    esac

    if [ "${CT_LIBC_DISABLE_VERSIONING}" = "y" ]; then
        extra_config+=("--disable-versioning")
    fi

    if [ "${CT_LIBC_OLDEST_ABI}" != "" ]; then
        extra_config+=("--enable-oldest-abi=${CT_LIBC_OLDEST_ABI}")
    fi

    case "$(do_libc_add_ons_list ,)" in
        "") ;;
        *)  extra_config+=("--enable-add-ons=$(do_libc_add_ons_list ,)");;
    esac

    extra_cc_args="${extra_cc_args} ${CT_ARCH_ENDIAN_OPT}"

    touch config.cache
    if [ "${CT_LIBC_GLIBC_FORCE_UNWIND}" = "y" ]; then
        echo "libc_cv_forced_unwind=yes" >>config.cache
        echo "libc_cv_c_cleanup=yes" >>config.cache
    fi

    # Pre-seed the configparms file with values from the config option
    printf "${CT_LIBC_GLIBC_CONFIGPARMS}\n" > configparms

    cross_cc=$(CT_Which "${CT_TARGET}-gcc")    

    CT_DoLog DEBUG "Using gcc for target:     '${cross_cc}'"
    CT_DoLog DEBUG "Configuring with addons : '$(do_libc_add_ons_list ,)'"
    CT_DoLog DEBUG "Extra config args passed: '${extra_config[*]}'"
    CT_DoLog DEBUG "Extra CC args passed    : '${extra_cc_args}'"

    glibc_cflags="${CT_TARGET_CFLAGS} ${CT_LIBC_GLIBC_EXTRA_CFLAGS} ${OPTIMIZE}"
    case "${CT_LIBC_ENABLE_FORTIFIED_BUILD}" in
        y)  ;;
        *)  glibc_cflags+=" -U_FORTIFY_SOURCE";;
    esac

    # ./configure is mislead by our tools override wrapper for bash
    # so just tell it where the real bash is _on_the_target_!
    # Notes:
    # - ${ac_cv_path_BASH_SHELL} is only used to set BASH_SHELL
    # - ${BASH_SHELL}            is only used to set BASH
    # - ${BASH}                  is only used to set the shebang
    #                            in two scripts to run on the target
    # So we can safely bypass bash detection at compile time.
    # Should this change in a future eglibc release, we'd better
    # directly mangle the generated scripts _after_ they get built,
    # or even after they get installed... eglibc is such a sucker...
    echo "ac_cv_path_BASH_SHELL=/bin/bash" >>config.cache

    # Configure with --prefix the way we want it on the target...
    # There are a whole lot of settings here.  You'll probably want
    # to read up on what they all mean, and customize a bit, possibly by setting GLIBC_EXTRA_CONFIG
    # Compare these options with the ones used when installing the glibc headers above - they're different.
    # Adding "--without-gd" option to avoid error "memusagestat.c:36:16: gd.h: No such file or directory"
    # See also http://sources.redhat.com/ml/libc-alpha/2000-07/msg00024.html.
    # Set BUILD_CC, or we won't be able to build datafiles

    CT_DoExecLog CFG                                                \
    BUILD_CC="${CT_BUILD}-gcc"                                      \
    CFLAGS="${glibc_cflags}"                                        \
    CC="${CT_TARGET}-gcc ${CT_LIBC_EXTRA_CC_ARGS} ${extra_cc_args}" \
    AR=${CT_TARGET}-ar                                              \
    RANLIB=${CT_TARGET}-ranlib                                      \
    "${src_dir}/configure"                                          \
        --prefix=/usr                                               \
        --build=${CT_BUILD}                                         \
        --host=${CT_TARGET}                                         \
        --cache-file="$(pwd)/config.cache"                          \
        --without-cvs                                               \
        --disable-profile                                           \
        --without-gd                                                \
        --with-headers="${CT_HEADERS_DIR}"                          \
        "${extra_config[@]}"                                        \
        ${CT_LIBC_GLIBC_EXTRA_CONFIG}
    
    # build hacks
    case "${CT_ARCH},${CT_ARCH_CPU}" in
        powerpc,8??)
            # http://sourceware.org/ml/crossgcc/2008-10/msg00068.html
            CT_DoLog DEBUG "Activating support for memset on broken ppc-8xx (CPU15 erratum)"
            extra_make_args+=( ASFLAGS="-DBROKEN_PPC_8xx_CPU15" )
            ;;
    esac

    CT_DoLog EXTRA "Building C library"
    CT_DoExecLog ALL make ${JOBSFLAGS}                      \
                          "${extra_make_args[@]}"           \
                          all

    CT_DoLog EXTRA "Installing C library"
    CT_DoExecLog ALL make ${JOBSFLAGS}                      \
                          "${extra_make_args[@]}"           \
                          install_root="${CT_SYSROOT_DIR}"  \
                          install

    CT_EndStep
}

# This function finishes the C library install
# This is a no-op
do_libc_finish() {
    :
}

# Build up the addons list, separated with $1
do_libc_add_ons_list() {
    local sep="$1"
    local addons_list="$( echo "${CT_LIBC_ADDONS_LIST}"         \
                          |sed -r -e "s/[[:space:],]/${sep}/g;" \
                        )"
    case "${CT_THREADS}" in
        none)   ;;
        *)      addons_list="${addons_list}${sep}${CT_THREADS}";;
    esac
    [ "${CT_LIBC_GLIBC_USE_PORTS}" = "y" ] && addons_list="${addons_list}${sep}ports"
    # Remove duplicate, leading and trailing separators
    echo "${addons_list}" |sed -r -e "s/${sep}+/${sep}/g; s/^${sep}//; s/${sep}\$//;"
}

# Compute up the minimum supported Linux kernel version
do_libc_min_kernel_config() {
    local min_kernel_config

    case "${CT_LIBC_GLIBC_EXTRA_CONFIG}" in
        *--enable-kernel*) ;;
        *)  if [ "${CT_LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS}" = "y" ]; then
                # We can't rely on the kernel version from the configuration,
                # because it might not be available if the user uses pre-installed
                # headers. On the other hand, both method will have the kernel
                # version installed in "usr/include/linux/version.h" in the sysroot.
                # Parse that instead of having two code-paths.
                version_code_file="${CT_SYSROOT_DIR}/usr/include/linux/version.h"
                if [ ! -f "${version_code_file}" -o ! -r "${version_code_file}" ]; then
                    CT_Abort "Linux version is unavailable in installed headers files"
                fi
                version_code="$( grep -E LINUX_VERSION_CODE "${version_code_file}"  \
                                 |cut -d ' ' -f 3                                   \
                               )"
                version=$(((version_code>>16)&0xFF))
                patchlevel=$(((version_code>>8)&0xFF))
                sublevel=$((version_code&0xFF))
                min_kernel_config="${version}.${patchlevel}.${sublevel}"
            elif [ "${CT_LIBC_GLIBC_KERNEL_VERSION_CHOSEN}" = "y" ]; then
                # Trim the fourth part of the linux version, keeping only the first three numbers
                min_kernel_config="$( echo "${CT_LIBC_GLIBC_MIN_KERNEL_VERSION}"            \
                                      |sed -r -e 's/^([^.]+\.[^.]+\.[^.]+)(|\.[^.]+)$/\1/;' \
                                    )"
            fi
            echo "--enable-kernel=${min_kernel_config}"
            ;;
    esac
}