crosstool-ng/scripts/functions

# This file contains some usefull common functions
# Copyright 2007 Yann E. MORIN
# Licensed under the GPL v2. See COPYING in the root of this package

# Prepare the fault handler
CT_OnError() {
    ret=$?
    # Bail out early in subshell, the upper level shell will act accordingly.
    [ ${BASH_SUBSHELL} -eq 0 ] || exit $ret
    CT_DoLog ERROR "Build failed in step '${CT_STEP_MESSAGE[${CT_STEP_COUNT}]}'"
    for((step=(CT_STEP_COUNT-1); step>1; step--)); do
        CT_DoLog ERROR "      called in step '${CT_STEP_MESSAGE[${step}]}'"
    done
    CT_DoLog ERROR "Error happened in '${BASH_SOURCE[1]}' in function '${FUNCNAME[1]}' (line unknown, sorry)"
    for((depth=2; ${BASH_LINENO[$((${depth}-1))]}>0; depth++)); do
        CT_DoLog ERROR "      called from '${BASH_SOURCE[${depth}]}' at line # ${BASH_LINENO[${depth}-1]} in function '${FUNCNAME[${depth}]}'"
    done
    [ "${CT_LOG_TO_FILE}" = "y" ] && CT_DoLog ERROR "Look at '${CT_LOG_FILE}' for more info on this error."
    CT_STEP_COUNT=1
    CT_DoEnd ERROR
    exit $ret
}

# Install the fault handler
trap CT_OnError ERR

# Inherit the fault handler in subshells and functions
set -E

# Make pipes fail on the _first_ failed command
# Not supported on bash < 3.x, but we need it, so drop the obsoleting bash-2.x
set -o pipefail

# Don't hash commands' locations, and search every time it is requested.
# This is slow, but needed because of the static/shared core gcc which shall
# always match to shared if it exists, and only fallback to static if the
# shared is not found
set +o hashall

# Log policy:
#  - first of all, save stdout so we can see the live logs: fd #6
exec 6>&1
#  - then point stdout to the log file (temporary for now)
tmp_log_file="${CT_TOP_DIR}/log.$$"
exec >>"${tmp_log_file}"

# The different log levels:
CT_LOG_LEVEL_ERROR=0
CT_LOG_LEVEL_WARN=1
CT_LOG_LEVEL_INFO=2
CT_LOG_LEVEL_EXTRA=3
CT_LOG_LEVEL_CFG=4
CT_LOG_LEVEL_FILE=5
CT_LOG_LEVEL_ALL=6
CT_LOG_LEVEL_DEBUG=7

# Make it easy to use \n and !
CR=$(printf "\n")
BANG='!'

# A function to log what is happening
# Different log level are available:
#   - ERROR:   A serious, fatal error occurred
#   - WARN:    A non fatal, non serious error occurred, take your responsbility with the generated build
#   - INFO:    Informational messages
#   - EXTRA:   Extra informational messages
#   - DEBUG:   Debug messages
#   - CFG:     Output of various "./configure"-type scripts
#   - FILE:    File / archive unpacking.
#   - ALL:     Component's build messages
# Usage: CT_DoLog <level> [message]
# If message is empty, then stdin will be logged.
CT_DoLog() {
    local max_level LEVEL level cur_l cur_L
    local l
    eval max_level="\${CT_LOG_LEVEL_${CT_LOG_LEVEL_MAX}}"
    # Set the maximum log level to DEBUG if we have none
    [ -z "${max_level}" ] && max_level=${CT_LOG_LEVEL_DEBUG}

    LEVEL="$1"; shift
    eval level="\${CT_LOG_LEVEL_${LEVEL}}"

    if [ $# -eq 0 ]; then
        cat -
    else
        printf "%s\n" "${*}"
    fi |( IFS="${CR}" # We want the full lines, even leading spaces
          _prog_bar_cpt=0
          _prog_bar[0]='/'
          _prog_bar[1]='-'
          _prog_bar[2]='\'
          _prog_bar[3]='|'
          indent=$((2*CT_STEP_COUNT))
          while read line; do
              case "${CT_LOG_SEE_TOOLS_WARN},${line}" in
                y,*"warning:"*)         cur_L=WARN; cur_l=${CT_LOG_LEVEL_WARN};;
                y,*"WARNING:"*)         cur_L=WARN; cur_l=${CT_LOG_LEVEL_WARN};;
                *"error:"*)             cur_L=ERROR; cur_l=${CT_LOG_LEVEL_ERROR};;
                *"make["*"]: *** ["*)   cur_L=ERROR; cur_l=${CT_LOG_LEVEL_ERROR};;
                *)                      cur_L="${LEVEL}"; cur_l="${level}";;
              esac
              # There will always be a log file (stdout, fd #1), be it /dev/null
              printf "[%-5s]%*s%s%s\n" "${cur_L}" "${indent}" " " "${line}"
              if [ ${cur_l} -le ${max_level} ]; then
                  # Only print to console (fd #6) if log level is high enough.
                  printf "\r[%-5s]%*s%s%s\n" "${cur_L}" "${indent}" " " "${line}" >&6
              fi
              if [ "${CT_LOG_PROGRESS_BAR}" = "y" ]; then
                  printf "\r[%02d:%02d] %s " $((SECONDS/60)) $((SECONDS%60)) "${_prog_bar[$((_prog_bar_cpt/10))]}" >&6
                  _prog_bar_cpt=$(((_prog_bar_cpt+1)%40))
              fi
          done
        )

    return 0
}

# Execute an action, and log its messages
# Usage: [VAR=val...] CT_DoExecLog <level> <command [parameters...]>
CT_DoExecLog() {
    local level="$1"
    shift
    CT_DoLog DEBUG "==> Executing: '${*}'"
    "${@}" 2>&1 |CT_DoLog "${level}"
}

# Tail message to be logged whatever happens
# Usage: CT_DoEnd <level>
CT_DoEnd()
{
    local level="$1"
    CT_STOP_DATE=$(CT_DoDate +%s%N)
    CT_STOP_DATE_HUMAN=$(CT_DoDate +%Y%m%d.%H%M%S)
    if [ "${level}" != "ERROR" ]; then
        CT_DoLog "${level:-INFO}" "Build completed at ${CT_STOP_DATE_HUMAN}"
    fi
    elapsed=$((CT_STOP_DATE-CT_STAR_DATE))
    elapsed_min=$((elapsed/(60*1000*1000*1000)))
    elapsed_sec=$(printf "%02d" $(((elapsed%(60*1000*1000*1000))/(1000*1000*1000))))
    elapsed_csec=$(printf "%02d" $(((elapsed%(1000*1000*1000))/(10*1000*1000))))
    CT_DoLog ${level:-INFO} "(elapsed: ${elapsed_min}:${elapsed_sec}.${elapsed_csec})"
}

# Remove entries referring to . and other relative paths
# Usage: CT_SanitizePath
CT_SanitizePath() {
    local new
    local p
    local IFS=:
    for p in $PATH; do
        # Only accept absolute paths;
        # Note: as a special case the empty string in PATH is equivalent to .
        if [ -n "${p}" -a -z "${p%%/*}" ]; then
            new="${new}${new:+:}${p}"
        fi
    done
    PATH="${new}"
}

# Abort the execution with an error message
# Usage: CT_Abort <message>
CT_Abort() {
    CT_DoLog ERROR "$1"
    exit 1
}

# Test a condition, and print a message if satisfied
# Usage: CT_Test <message> <tests>
CT_Test() {
    local ret
    local m="$1"
    shift
    CT_DoLog DEBUG "Testing '! ( $* )'"
    test "$@" && CT_DoLog WARN "$m"
    return 0
}

# Test a condition, and abort with an error message if satisfied
# Usage: CT_TestAndAbort <message> <tests>
CT_TestAndAbort() {
    local m="$1"
    shift
    CT_DoLog DEBUG "Testing '! ( $* )'"
    test "$@" && CT_Abort "$m"
    return 0
}

# Test a condition, and abort with an error message if not satisfied
# Usage: CT_TestAndAbort <message> <tests>
CT_TestOrAbort() {
    local m="$1"
    shift
    CT_DoLog DEBUG "Testing '$*'"
    test "$@" || CT_Abort "$m"
    return 0
}

# Test the presence of a tool, or abort if not found
# Usage: CT_HasOrAbort <tool>
CT_HasOrAbort() {
    CT_TestAndAbort "'${1}' not found and needed for successful toolchain build." -z "$(CT_Which "${1}")"
    return 0
}

# Search a program: wrap "which" for those system where
# "which" verbosely says there is no match (Mandriva is
# such a sucker...)
# Usage: CT_Which <filename>
CT_Which() {
  which "$1" 2>/dev/null || true
}

# Get current date with nanosecond precision
# On those system not supporting nanosecond precision, faked with rounding down
# to the highest entire second
# Usage: CT_DoDate <fmt>
CT_DoDate() {
    date "$1" |sed -r -e 's/N$/000000000/;'
}

CT_STEP_COUNT=1
CT_STEP_MESSAGE[${CT_STEP_COUNT}]="<none>"
# Memorise a step being done so that any error is caught
# Usage: CT_DoStep <loglevel> <message>
CT_DoStep() {
    local start=$(CT_DoDate +%s%N)
    CT_DoLog "$1" "================================================================="
    CT_DoLog "$1" "$2"
    CT_STEP_COUNT=$((CT_STEP_COUNT+1))
    CT_STEP_LEVEL[${CT_STEP_COUNT}]="$1"; shift
    CT_STEP_START[${CT_STEP_COUNT}]="${start}"
    CT_STEP_MESSAGE[${CT_STEP_COUNT}]="$1"
    return 0
}

# End the step just being done
# Usage: CT_EndStep
CT_EndStep() {
    local stop=$(CT_DoDate +%s%N)
    local duration=$(printf "%032d" $((stop-${CT_STEP_START[${CT_STEP_COUNT}]})) |sed -r -e 's/([[:digit:]]{2})[[:digit:]]{7}$/\.\1/; s/^0+//; s/^\./0\./;')
    local elapsed=$(printf "%02d:%02d" $((SECONDS/60)) $((SECONDS%60)))
    local level="${CT_STEP_LEVEL[${CT_STEP_COUNT}]}"
    local message="${CT_STEP_MESSAGE[${CT_STEP_COUNT}]}"
    CT_STEP_COUNT=$((CT_STEP_COUNT-1))
    CT_DoLog "${level}" "${message}: done in ${duration}s (at ${elapsed})"
    return 0
}

# Pushes into a directory, and pops back
CT_Pushd() {
    pushd "$1" >/dev/null 2>&1
}
CT_Popd() {
    popd >/dev/null 2>&1
}

# Creates a temporary directory
# $1: variable to assign to
# Usage: CT_MktempDir foo
CT_MktempDir() {
    # Some mktemp do not allow more than 6 Xs
    eval "$1"=$(mktemp -q -d "${CT_BUILD_DIR}/tmp.XXXXXX")
    CT_TestOrAbort "Could not make temporary directory" -n "${!1}" -a -d "${!1}"
    CT_DoLog DEBUG "Made temporary directory '${!1}'"
    return 0
}

# Removes one or more directories, even if it is read-only, or its parent is
# Usage: CT_DoForceRmdir dir [...]
CT_DoForceRmdir() {
    local dir
    local mode
    for dir in "${@}"; do
        [ -d "${dir}" ] || continue
        case "$CT_SYS_OS" in
            Linux|CYGWIN*)
                mode="$(stat -c '%a' "$(dirname "${dir}")")"
                ;;
            Darwin|*BSD)
                mode="$(stat -f '%Lp' "$(dirname "${dir}")")"
                ;;
            *)
                CT_Abort "Unhandled host OS $CT_SYS_OS"
                ;;
        esac
        CT_DoExecLog ALL chmod u+w "$(dirname "${dir}")"
        CT_DoExecLog ALL chmod -R u+w "${dir}"
        CT_DoExecLog ALL rm -rf "${dir}"
        CT_DoExecLog ALL chmod ${mode} "$(dirname "${dir}")"
    done
}

# Echoes the specified string on stdout until the pipe breaks.
# Doesn't fail
# $1: string to echo
# Usage: CT_DoYes "" |make oldconfig
CT_DoYes() {
    yes "$1" || true
}

# Add the specified directory to LD_LIBRARY_PATH, and export it
# If the specified patch is already present, just export
# $1: path to add
# $2: add as 'first' or 'last' path, 'first' is assumed if $2 is empty
# Usage CT_SetLibPath /some/where/lib [first|last]
CT_SetLibPath() {
    local path="$1"
    local pos="$2"

    case ":${LD_LIBRARY_PATH}:" in
        *:"${path}":*)  ;;
        *)  case "${pos}" in
                last)
                    CT_DoLog DEBUG "Adding '${path}' at end of LD_LIBRARY_PATH"
                    LD_LIBRARY_PATH="${LD_LIBRARY_PATH:+${LD_LIBRARY_PATH}:}${path}"
                    ;;
                first|"")
                    CT_DoLog DEBUG "Adding '${path}' at start of LD_LIBRARY_PATH"
                    LD_LIBRARY_PATH="${path}${LD_LIBRARY_PATH:+:${LD_LIBRARY_PATH}}"
                    ;;
                *)
                    CT_Abort "Incorrect position '${pos}' to add '${path}' to LD_LIBRARY_PATH"
                    ;;
            esac
            ;;
    esac
    CT_DoLog DEBUG "==> LD_LIBRARY_PATH='${LD_LIBRARY_PATH}'"
    export LD_LIBRARY_PATH
}

# Get the file name extension of a component
# Usage: CT_GetFileExtension <component_name-component_version> [extension]
# If found, echoes the extension to stdout, and return 0
# If not found, echoes nothing on stdout, and return !0.
CT_GetFileExtension() {
    local ext
    local file="$1"
    shift
    local first_ext="$1"

    # we need to also check for an empty extension for those very
    # peculiar components that don't have one (such as sstrip from
    # buildroot).
    for ext in ${first_ext} .tar.gz .tar.bz2 .tgz .tar /.git ''; do
        if [ -e "${CT_TARBALLS_DIR}/${file}${ext}" ]; then
            echo "${ext}"
            exit 0
        fi
    done

    exit 1
}

# Download an URL using wget
# Usage: CT_DoGetFileWget <URL>
CT_DoGetFileWget() {
    # Need to return true because it is legitimate to not find the tarball at
    # some of the provided URLs (think about snapshots, different layouts for
    # different gcc versions, etc...)
    # Some (very old!) FTP server might not support the passive mode, thus
    # retry without
    # With automated download as we are doing, it can be very dangerous to use
    # -c to continue the downloads. It's far better to simply overwrite the
    # destination file
    # Some company networks have firewalls to connect to the internet, but it's
    # not easy to detect them, and wget does not timeout by default while
    # connecting, so force a global ${CT_CONNECT_TIMEOUT}-second timeout.
    CT_DoExecLog ALL wget -T ${CT_CONNECT_TIMEOUT} -nc --progress=dot:binary --tries=3 --passive-ftp "$1"    \
    || CT_DoExecLog ALL wget -T ${CT_CONNECT_TIMEOUT} -nc --progress=dot:binary --tries=3 "$1"               \
    || rm -f "${1##*/}"
}

# Download an URL using curl
# Usage: CT_DoGetFileCurl <URL>
CT_DoGetFileCurl() {
    # Note: comments about wget method (above) are also valid here
    # Plus: no good progress indicator is available with curl,
    #       so, be silent.
    CT_DoExecLog ALL curl -s --ftp-pasv -O --retry 3 "$1" --connect-timeout ${CT_CONNECT_TIMEOUT} -L -f  \
    || CT_DoExecLog ALL curl -s -O --retry 3 "$1" --connect-timeout ${CT_CONNECT_TIMEOUT} -L -f          \
    || rm -f "${1##*/}"
}

# Download using aria2
# Usage: CT_DoGetFileAria2 <URL>
CT_DoGetFileAria2() {
    # Note: comments about curl method (above) are also valid here
    # Plus: default progress indicator is a single line, so use verbose log
    #       so that the CT-NG's ouput is 'live'.
    CT_DoExecLog ALL aria2c --summary-interval=1 -s ${CT_DOWNLOAD_MAX_CHUNKS} -m 3 -t ${CT_CONNECT_TIMEOUT} -p "$1" \
    || CT_DoExecLog ALL aria2c --summary-interval=1 -s ${CT_DOWNLOAD_MAX_CHUNKS} -m 3 -t ${CT_CONNECT_TIMEOUT} "$1" \
    || rm -f "${1##*/}"
}

# OK, just look if we have them...
_aria2c=$(CT_Which aria2c)
_wget=$(CT_Which wget)
_curl=$(CT_Which curl)

# Wrapper function to call one of, in order of preference:
#   aria2
#   curl
#   wget
# Usage: CT_DoGetFile <URL>
CT_DoGetFile() {
    if   [ -n "${_aria2c}" -a ${CT_DOWNLOAD_MAX_CHUNKS} -gt 1 ]; then
        CT_DoGetFileAria2 "$1"
    elif [ -n "${_curl}" ]; then
        CT_DoGetFileCurl "$1"
    elif [ -n "${_wget}" ]; then
        CT_DoGetFileWget "$1"
    else
        CT_Abort "Could find neither wget nor curl"
    fi
}

# This function tries to retrieve a tarball form a local directory
# Usage: CT_GetLocal <basename> [.extension]
CT_GetLocal() {
    local basename="$1"
    local first_ext="$2"
    local ext

    # Do we already have it in *our* tarballs dir?
    if ext="$( CT_GetFileExtension "${basename}" ${first_ext} )"; then
        CT_DoLog DEBUG "Already have '${basename}'"
        return 0
    fi

    if [ -n "${CT_LOCAL_TARBALLS_DIR}" ]; then
        CT_DoLog DEBUG "Trying to retrieve an already downloaded copy of '${basename}'"
        # We'd rather have a bzip2'ed tarball, then gzipped tarball, plain tarball,
        # or, as a failover, a file without extension.
        for ext in ${first_ext} .tar.bz2 .tar.gz .tgz .tar ''; do
            CT_DoLog DEBUG "Trying '${CT_LOCAL_TARBALLS_DIR}/${basename}${ext}'"
            if [ -r "${CT_LOCAL_TARBALLS_DIR}/${basename}${ext}" -a \
                 "${CT_FORCE_DOWNLOAD}" != "y" ]; then
                CT_DoLog DEBUG "Got '${basename}' from local storage"
                CT_DoExecLog ALL ln -s "${CT_LOCAL_TARBALLS_DIR}/${basename}${ext}" "${CT_TARBALLS_DIR}/${basename}${ext}"
                return 0
            fi
        done
    fi
    return 1
}

# This function saves the specified to local storage if possible,
# and if so, symlinks it for later usage
# Usage: CT_SaveLocal </full/path/file.name>
CT_SaveLocal() {
    local file="$1"
    local basename="${file##*/}"

    if [ "${CT_SAVE_TARBALLS}" = "y" ]; then
        CT_DoLog EXTRA "Saving '${basename}' to local storage"
        # The file may already exist if downloads are forced: remove it first
        CT_DoExecLog ALL rm -f "${CT_LOCAL_TARBALLS_DIR}/${basename}"
        CT_DoExecLog ALL mv -f "${file}" "${CT_LOCAL_TARBALLS_DIR}"
        CT_DoExecLog ALL ln -s "${CT_LOCAL_TARBALLS_DIR}/${basename}" "${file}"
    fi
}

# Download the file from one of the URLs passed as argument
# Usage: CT_GetFile <basename> [.extension] <url> [url ...]
CT_GetFile() {
    local ext
    local url URLS LAN_URLS
    local file="$1"
    local first_ext
    shift
    # If next argument starts with a dot, then this is not an URL,
    # and we can consider that it is a preferred extension.
    case "$1" in
        .*) first_ext="$1"
            shift
            ;;
    esac

    # Does it exist localy?
    CT_GetLocal "${file}" ${first_ext} && return 0 || true
    # No, it does not...

    # Try to retrieve the file
    CT_DoLog EXTRA "Retrieving '${file}'"
    CT_Pushd "${CT_TARBALLS_DIR}"

    URLS="$@"

    # Add URLs on the LAN mirror
    LAN_URLS=
    if [ "${CT_USE_MIRROR}" = "y" ]; then
        CT_TestOrAbort "Please set the mirror base URL" -n "${CT_MIRROR_BASE_URL}"
        LAN_URLS="${LAN_URLS} ${CT_MIRROR_BASE_URL}/${file%-*}"
        LAN_URLS="${LAN_URLS} ${CT_MIRROR_BASE_URL}"

        if [ "${CT_PREFER_MIRROR}" = "y" ]; then
            CT_DoLog DEBUG "Pre-pending LAN mirror URLs"
            URLS="${LAN_URLS} ${URLS}"
        else
            CT_DoLog DEBUG "Appending LAN mirror URLs"
            URLS="${URLS} ${LAN_URLS}"
        fi
    fi

    # Scan all URLs in turn, and try to grab a tarball from there
    # Do *not* try git trees (ext=/.git), this is handled in a specific
    # wrapper, below
    for ext in ${first_ext} .tar.bz2 .tar.gz .tgz .tar ''; do
        # Try all urls in turn
        for url in ${URLS}; do
            CT_DoLog DEBUG "Trying '${url}/${file}${ext}'"
            CT_DoGetFile "${url}/${file}${ext}"
            if [ -f "${file}${ext}" ]; then
                CT_DoLog DEBUG "Got '${file}' from the Internet"
                CT_SaveLocal "${CT_TARBALLS_DIR}/${file}${ext}"
                return 0
            fi
        done
    done
    CT_Popd

    CT_Abort "Could not retrieve '${file}'."
}

# Checkout from CVS, and build the associated tarball
# The tarball will be called ${basename}.tar.bz2
# Prerequisite: either the server does not require password,
# or the user must already be logged in.
# 'tag' is the tag to retrieve. Must be specified, but can be empty.
# If dirname is specified, then module will be renamed to dirname
# prior to building the tarball.
# Usage: CT_GetCVS <basename> <url> <module> <tag> [dirname[=subdir]]
# Note: if '=subdir' is given, then it is used instead of 'module'.
CT_GetCVS() {
    local basename="$1"
    local uri="$2"
    local module="$3"
    local tag="${4:+-r ${4}}"
    local dirname="$5"
    local tmp_dir

    # Does it exist localy?
    CT_GetLocal "${basename}" && return 0 || true
    # No, it does not...

    CT_DoLog EXTRA "Retrieving '${basename}'"

    CT_MktempDir tmp_dir
    CT_Pushd "${tmp_dir}"

    CT_DoExecLog ALL cvs -z 9 -d "${uri}" co -P ${tag} "${module}"
    if [ -n "${dirname}" ]; then
        case "${dirname}" in
            *=*)
                CT_DoExecLog DEBUG mv "${dirname#*=}" "${dirname%%=*}"
                CT_DoExecLog ALL tar cjf "${CT_TARBALLS_DIR}/${basename}.tar.bz2" "${dirname%%=*}"
                ;;
            *)
                CT_DoExecLog ALL mv "${module}" "${dirname}"
                CT_DoExecLog ALL tar cjf "${CT_TARBALLS_DIR}/${basename}.tar.bz2" "${dirname:-${module}}"
                ;;
        esac
    fi
    CT_SaveLocal "${CT_TARBALLS_DIR}/${basename}.tar.bz2"

    CT_Popd
    CT_DoExecLog ALL rm -rf "${tmp_dir}"
}

# Check out from SVN, and build the associated tarball
# The tarball will be called ${basename}.tar.bz2
# Prerequisite: either the server does not require password,
# or the user must already be logged in.
# 'rev' is the revision to retrieve
# Usage: CT_GetSVN <basename> <url> [rev]
CT_GetSVN() {
    local basename="$1"
    local uri="$2"
    local rev="$3"

    # Does it exist localy?
    CT_GetLocal "${basename}" && return 0 || true
    # No, it does not...

    CT_DoLog EXTRA "Retrieving '${basename}'"

    CT_MktempDir tmp_dir
    CT_Pushd "${tmp_dir}"

    CT_DoExecLog ALL svn export ${rev:+-r ${rev}} "${uri}" "${basename}"
    CT_DoExecLog ALL tar cjf "${CT_TARBALLS_DIR}/${basename}.tar.bz2" "${basename}"
    CT_SaveLocal "${CT_TARBALLS_DIR}/${basename}.tar.bz2"

    CT_Popd
    CT_DoExecLog ALL rm -rf "${tmp_dir}"
}

# Clone a git tree
# Tries the given URLs in turn until one can get cloned. No tarball will be created.
# Prerequisites: either the server does not require password,
# or the user has already taken any action to authenticate to the server.
# The cloned tree will *not* be stored in the local tarballs dir!
# Usage: CT_GetGit <basename> <url [url ...]>
CT_GetGit() {
    local basename="$1"; shift
    local url
    local cloned=0

    # Do we have it in our tarballs dir?
    if [ -d "${CT_TARBALLS_DIR}/${basename}/.git" ]; then
        CT_DoLog EXTRA "Updating git tree '${basename}'"
        CT_Pushd "${CT_TARBALLS_DIR}/${basename}"
        CT_DoExecLog ALL git pull
        CT_Popd
    else
        CT_DoLog EXTRA "Retrieving git tree '${basename}'"
        for url in "${@}"; do
            CT_DoLog ALL "Trying to clone from '${url}'"
            CT_DoForceRmdir "${CT_TARBALLS_DIR}/${basename}"
            if git clone "${url}" "${CT_TARBALLS_DIR}/${basename}" 2>&1 |CT_DoLog ALL; then
                cloned=1
                break
            fi
        done
        CT_TestOrAbort "Could not clone '${basename}'" ${cloned} -ne 0
    fi
}

# Extract a tarball
# Some tarballs need to be extracted in specific places. Eg.: glibc addons
# must be extracted in the glibc directory; uCLibc locales must be extracted
# in the extra/locale sub-directory of uClibc. This is taken into account
# by the caller, that did a 'cd' into the correct path before calling us
# and sets nochdir to 'nochdir'.
# Note also that this function handles the git trees!
# Usage: CT_Extract <basename> [nochdir] [options]
# where 'options' are dependent on the source (eg. git branch/tag...)
CT_Extract() {
    local nochdir="$1"
    local basename
    local ext

    if [ "${nochdir}" = "nochdir" ]; then
        shift
        nochdir="$(pwd)"
    else
        nochdir="${CT_SRC_DIR}"
    fi

    basename="$1"
    shift

    if ! ext="$(CT_GetFileExtension "${basename}")"; then
      CT_Abort "'${basename}' not found in '${CT_TARBALLS_DIR}'"
    fi
    local full_file="${CT_TARBALLS_DIR}/${basename}${ext}"

    # Check if already extracted
    if [ -e "${CT_SRC_DIR}/.${basename}.extracted" ]; then
        CT_DoLog DEBUG "Already extracted '${basename}'"
        return 0
    fi

    # Check if previously partially extracted
    if [ -e "${CT_SRC_DIR}/.${basename}.extracting" ]; then
        CT_DoLog ERROR "The '${basename}' sources were partially extracted."
        CT_DoLog ERROR "Please remove first:"
        CT_DoLog ERROR " - the source dir for '${basename}', in '${CT_SRC_DIR}'"
        CT_DoLog ERROR " - the file '${CT_SRC_DIR}/.${basename}.extracting'"
        CT_Abort "I'll stop now to avoid any carnage..."
    fi
    CT_DoExecLog DEBUG touch "${CT_SRC_DIR}/.${basename}.extracting"

    CT_Pushd "${nochdir}"

    CT_DoLog EXTRA "Extracting '${basename}'"
    case "${ext}" in
        .tar.bz2)     CT_DoExecLog FILE tar xvjf "${full_file}";;
        .tar.gz|.tgz) CT_DoExecLog FILE tar xvzf "${full_file}";;
        .tar)         CT_DoExecLog FILE tar xvf  "${full_file}";;
        /.git)        CT_ExtractGit "${basename}" "${@}";;
        *)            CT_Abort "Don't know how to handle '${basename}${ext}': unknown extension";;
    esac

    # Some tarballs have read-only files... :-(
    # Because of nochdir, we don't know where we are, so chmod all
    # the src tree
    CT_DoExecLog DEBUG chmod -R u+w "${CT_SRC_DIR}"

    # Don't mark as being extracted for git
    case "${ext}" in
        /.git)  ;;
        *)      CT_DoExecLog DEBUG touch "${CT_SRC_DIR}/.${basename}.extracted";;
    esac
    CT_DoExecLog DEBUG rm -f "${CT_SRC_DIR}/.${basename}.extracting"

    CT_Popd
}

# Create a working git clone
# Usage: CT_ExtractGit <basename> [ref]
# where 'ref' is the reference to use:
#   the full name of a branch, like "remotes/origin/branch_name"
#   a date as understandable by git, like "YYYY-MM-DD[ hh[:mm[:ss]]]"
#   a tag name
CT_ExtractGit() {
    local basename="${1}"
    local ref="${2}"
    local clone_dir
    local ref_type

    # pushd now to be able to get git revlist in case ref is a date
    clone_dir="${CT_TARBALLS_DIR}/${basename}"
    CT_Pushd "${clone_dir}"

    # What kind of reference is ${ref} ?
    if [ -z "${ref}" ]; then
        # Don't update the clone, keep as-is
        ref_type=none
    elif git tag |grep -E "^${ref}$" >/dev/null 2>&1; then
        ref_type=tag
    elif git branch -a --no-color |grep -E "^. ${ref}$" >/dev/null 2>&1; then
        ref_type=branch
    elif date -d "${ref}" >/dev/null 2>&1; then
        ref_type=date
        ref=$(git rev-list -n1 --before="${ref}")
    else
        CT_Abort "Reference '${ref}' is an incorrect git reference: neither tag, branch nor date"
    fi

    CT_DoExecLog DEBUG rm -f "${CT_SRC_DIR}/${basename}"
    CT_DoExecLog ALL ln -sf "${clone_dir}" "${CT_SRC_DIR}/${basename}"

    case "${ref_type}" in
        none)   ;;
        *)      CT_DoExecLog FILE git checkout "${ref}";;
    esac

    CT_Popd
}

# Patches the specified component
# See CT_Extract, above, for explanations on 'nochdir'
# Usage: CT_Patch [nochdir] <packagename> <packageversion>
# If the package directory is *not* packagename-packageversion, then
# the caller must cd into the proper directory first, and call us
# with nochdir
CT_Patch() {
    local nochdir="$1"
    local pkgname
    local version
    local pkgdir
    local base_file
    local ver_file
    local d
    local -a patch_dirs
    local bundled_patch_dir
    local local_patch_dir

    if [ "${nochdir}" = "nochdir" ]; then
        shift
        pkgname="$1"
        version="$2"
        pkgdir="${pkgname}-${version}"
        nochdir="$(pwd)"
    else
        pkgname="$1"
        version="$2"
        pkgdir="${pkgname}-${version}"
        nochdir="${CT_SRC_DIR}/${pkgdir}"
    fi

    # Check if already patched
    if [ -e "${CT_SRC_DIR}/.${pkgdir}.patched" ]; then
        CT_DoLog DEBUG "Already patched '${pkgdir}'"
        return 0
    fi

    # Check if already partially patched
    if [ -e "${CT_SRC_DIR}/.${pkgdir}.patching" ]; then
        CT_DoLog ERROR "The '${pkgdir}' sources were partially patched."
        CT_DoLog ERROR "Please remove first:"
        CT_DoLog ERROR " - the source dir for '${pkgdir}', in '${CT_SRC_DIR}'"
        CT_DoLog ERROR " - the file '${CT_SRC_DIR}/.${pkgdir}.extracted'"
        CT_DoLog ERROR " - the file '${CT_SRC_DIR}/.${pkgdir}.patching'"
        CT_Abort "I'll stop now to avoid any carnage..."
    fi
    touch "${CT_SRC_DIR}/.${pkgdir}.patching"

    CT_Pushd "${nochdir}"

    CT_DoLog EXTRA "Patching '${pkgdir}'"

    bundled_patch_dir="${CT_LIB_DIR}/patches/${pkgname}/${version}"
    local_patch_dir="${CT_LOCAL_PATCH_DIR}/${pkgname}/${version}"

    case "${CT_PATCH_ORDER}" in
        bundled)        patch_dirs=("${bundled_patch_dir}");;
        local)          patch_dirs=("${local_patch_dir}");;
        bundled,local)  patch_dirs=("${bundled_patch_dir}" "${local_patch_dir}");;
        local,bundled)  patch_dirs=("${local_patch_dir}" "${bundled_patch_dir}");;
        none)           patch_dirs=;;
    esac

    for d in "${patch_dirs[@]}"; do
        CT_DoLog DEBUG "Looking for patches in '${d}'..."
        if [ -n "${d}" -a -d "${d}" ]; then
            for p in "${d}"/*.patch; do
                if [ -f "${p}" ]; then
                    CT_DoLog DEBUG "Applying patch '${p}'"
                    CT_DoExecLog ALL patch --no-backup-if-mismatch -g0 -F1 -p1 -f <"${p}"
                fi
            done
            if [ "${CT_PATCH_SINGLE}" = "y" ]; then
                break
            fi
        fi
    done

    if [ "${CT_OVERIDE_CONFIG_GUESS_SUB}" = "y" ]; then
        CT_DoLog ALL "Overiding config.guess and config.sub"
        for cfg in config_guess config_sub; do
            eval ${cfg}="${CT_LIB_DIR}/scripts/${cfg/_/.}"
            [ -e "${CT_TOP_DIR}/scripts/${cfg/_/.}" ] && eval ${cfg}="${CT_TOP_DIR}/scripts/${cfg/_/.}"
            # Can't use CT_DoExecLog because of the '{} \;' to be passed un-mangled to find
            find . -type f -name "${cfg/_/.}" -exec cp -v "${!cfg}" {} \; |CT_DoLog ALL
        done
    fi

    CT_DoExecLog DEBUG touch "${CT_SRC_DIR}/.${pkgdir}.patched"
    CT_DoExecLog DEBUG rm -f "${CT_SRC_DIR}/.${pkgdir}.patching"

    CT_Popd
}

# Two wrappers to call config.(guess|sub) either from CT_TOP_DIR or CT_LIB_DIR.
# Those from CT_TOP_DIR, if they exist, will be be more recent than those from CT_LIB_DIR.
CT_DoConfigGuess() {
    if [ -x "${CT_TOP_DIR}/scripts/config.guess" ]; then
        "${CT_TOP_DIR}/scripts/config.guess"
    else
        "${CT_LIB_DIR}/scripts/config.guess"
    fi
}

CT_DoConfigSub() {
    if [ -x "${CT_TOP_DIR}/scripts/config.sub" ]; then
        "${CT_TOP_DIR}/scripts/config.sub" "$@"
    else
        "${CT_LIB_DIR}/scripts/config.sub" "$@"
    fi
}

# Compute the target tuple from what is provided by the user
# Usage: CT_DoBuildTargetTuple
# In fact this function takes the environment variables to build the target
# tuple. It is needed both by the normal build sequence, as well as the
# sample saving sequence.
CT_DoBuildTargetTuple() {
    # Set the endianness suffix, and the default endianness gcc option
    case "${CT_ARCH_BE},${CT_ARCH_LE}" in
        y,) target_endian_eb=eb
            target_endian_el=
            CT_ARCH_ENDIAN_CFLAG="-mbig-endian"
            CT_ARCH_ENDIAN_LDFLAG="-EB"
            ;;
        ,y) target_endian_eb=
            target_endian_el=el
            CT_ARCH_ENDIAN_CFLAG="-mlittle-endian"
            CT_ARCH_ENDIAN_LDFLAG="-EL"
            ;;
    esac

    # Build the default architecture tuple part
    CT_TARGET_ARCH="${CT_ARCH}"

    # Set defaults for the system part of the tuple. Can be overriden
    # by architecture-specific values.
    case "${CT_LIBC}" in
        *glibc) CT_TARGET_SYS=gnu;;
        uClibc) CT_TARGET_SYS=uclibc;;
        *)      CT_TARGET_SYS=elf;;
    esac

    # Set the default values for ARCH, ABI, CPU, TUNE, FPU and FLOAT
    unset CT_ARCH_ARCH_CFLAG CT_ARCH_ABI_CFLAG CT_ARCH_CPU_CFLAG CT_ARCH_TUNE_CFLAG CT_ARCH_FPU_CFLAG CT_ARCH_FLOAT_CFLAG
    unset CT_ARCH_WITH_ARCH CT_ARCH_WITH_ABI CT_ARCH_WITH_CPU CT_ARCH_WITH_TUNE CT_ARCH_WITH_FPU CT_ARCH_WITH_FLOAT
    [ "${CT_ARCH_ARCH}"     ] && { CT_ARCH_ARCH_CFLAG="-march=${CT_ARCH_ARCH}";  CT_ARCH_WITH_ARCH="--with-arch=${CT_ARCH_ARCH}"; }
    [ "${CT_ARCH_ABI}"      ] && { CT_ARCH_ABI_CFLAG="-mabi=${CT_ARCH_ABI}";     CT_ARCH_WITH_ABI="--with-abi=${CT_ARCH_ABI}";    }
    [ "${CT_ARCH_CPU}"      ] && { CT_ARCH_CPU_CFLAG="-mcpu=${CT_ARCH_CPU}";     CT_ARCH_WITH_CPU="--with-cpu=${CT_ARCH_CPU}";    }
    [ "${CT_ARCH_TUNE}"     ] && { CT_ARCH_TUNE_CFLAG="-mtune=${CT_ARCH_TUNE}";  CT_ARCH_WITH_TUNE="--with-tune=${CT_ARCH_TUNE}"; }
    [ "${CT_ARCH_FPU}"      ] && { CT_ARCH_FPU_CFLAG="-mfpu=${CT_ARCH_FPU}";     CT_ARCH_WITH_FPU="--with-fpu=${CT_ARCH_FPU}";    }
    [ "${CT_ARCH_FLOAT_SW}" ] && { CT_ARCH_FLOAT_CFLAG="-msoft-float";           CT_ARCH_WITH_FLOAT="--with-float=soft";          }

    # Build the default kernel tuple part
    CT_TARGET_KERNEL="${CT_KERNEL}"

    # Overide the default values with the components specific settings
    CT_DoArchTupleValues
    CT_DoKernelTupleValues

    # Finish the target tuple construction
    CT_TARGET="${CT_TARGET_ARCH}"
    CT_TARGET="${CT_TARGET}${CT_TARGET_VENDOR:+-${CT_TARGET_VENDOR}}"
    CT_TARGET="${CT_TARGET}${CT_TARGET_KERNEL:+-${CT_TARGET_KERNEL}}"
    CT_TARGET="${CT_TARGET}${CT_TARGET_SYS:+-${CT_TARGET_SYS}}"

    # Sanity checks
    __sed_alias=""
    if [ -n "${CT_TARGET_ALIAS_SED_EXPR}" ]; then
        __sed_alias=$(echo "${CT_TARGET}" |sed -r -e "${CT_TARGET_ALIAS_SED_EXPR}")
    fi
    case ":${CT_TARGET_VENDOR}:${CT_TARGET_ALIAS}:${__sed_alias}:" in
      :*" "*:*:*:) CT_Abort "Don't use spaces in the vendor string, it breaks things.";;
      :*"-"*:*:*:) CT_Abort "Don't use dashes in the vendor string, it breaks things.";;
      :*:*" "*:*:) CT_Abort "Don't use spaces in the target alias, it breaks things.";;
      :*:*:*" "*:) CT_Abort "Don't use spaces in the target sed transform, it breaks things.";;
    esac

    # Canonicalise it
    CT_TARGET=$(CT_DoConfigSub "${CT_TARGET}")
    # Prepare the target CFLAGS
    CT_ARCH_TARGET_CFLAGS="${CT_ARCH_TARGET_CFLAGS} ${CT_ARCH_ENDIAN_CFLAG}"
    CT_ARCH_TARGET_CFLAGS="${CT_ARCH_TARGET_CFLAGS} ${CT_ARCH_ARCH_CFLAG}"
    CT_ARCH_TARGET_CFLAGS="${CT_ARCH_TARGET_CFLAGS} ${CT_ARCH_ABI_CFLAG}"
    CT_ARCH_TARGET_CFLAGS="${CT_ARCH_TARGET_CFLAGS} ${CT_ARCH_CPU_CFLAG}"
    CT_ARCH_TARGET_CFLAGS="${CT_ARCH_TARGET_CFLAGS} ${CT_ARCH_TUNE_CFLAG}"
    CT_ARCH_TARGET_CFLAGS="${CT_ARCH_TARGET_CFLAGS} ${CT_ARCH_FPU_CFLAG}"
    CT_ARCH_TARGET_CFLAGS="${CT_ARCH_TARGET_CFLAGS} ${CT_ARCH_FLOAT_CFLAG}"

    # Now on for the target LDFLAGS
    CT_ARCH_TARGET_LDFLAGS="${CT_ARCH_TARGET_LDFLAGS} ${CT_ARCH_ENDIAN_LDFLAG}"
}

# This function does pause the build until the user strikes "Return"
# Usage: CT_DoPause [optional_message]
CT_DoPause() {
    local foo
    local message="${1:-Pausing for your pleasure}"
    CT_DoLog INFO "${message}"
    read -p "Press 'Enter' to continue, or Ctrl-C to stop..." foo >&6
    return 0
}

# This function creates a tarball of the specified directory, but
# only if it exists
# Usage: CT_DoTarballIfExists <dir> <tarball_basename> [extra_tar_options [...]]
CT_DoTarballIfExists() {
    local dir="$1"
    local tarball="$2"
    shift 2
    local -a extra_tar_opts=( "$@" )
    local -a compress

    case "${CT_DEBUG_CT_SAVE_STEPS_GZIP}" in
        y)  compress=( gzip -c -3 - ); tar_ext=.gz;;
        *)  compress=( cat - );        tar_ext=;;
    esac

    if [ -d "${dir}" ]; then
        CT_DoLog DEBUG "  Saving '${dir}'"
        { tar c -C "${dir}" -v -f - "${extra_tar_opts[@]}" .    \
          |"${compress[@]}" >"${tarball}.tar${tar_ext}"         ;
        } 2>&1 |sed -r -e 's/^/    /;' |CT_DoLog DEBUG
    else
        CT_DoLog DEBUG "  Not saving '${dir}': does not exist"
    fi
}

# This function extracts a tarball to the specified directory, but
# only if the tarball exists
# Usage: CT_DoTarballIfExists <tarball_basename> <dir> [extra_tar_options [...]]
CT_DoExtractTarballIfExists() {
    local tarball="$1"
    local dir="$2"
    shift 2
    local -a extra_tar_opts=( "$@" )
    local -a uncompress

    case "${CT_DEBUG_CT_SAVE_STEPS_GZIP}" in
        y)  uncompress=( gzip -c -d ); tar_ext=.gz;;
        *)  uncompress=( cat );        tar_ext=;;
    esac

    if [ -f "${tarball}.tar${tar_ext}" ]; then
        CT_DoLog DEBUG "  Restoring '${dir}'"
        CT_DoForceRmdir "${dir}"
        CT_DoExecLog DEBUG mkdir -p "${dir}"
        { "${uncompress[@]}" "${tarball}.tar${tar_ext}"     \
          |tar x -C "${dir}" -v -f - "${extra_tar_opts[@]}" ;
        } 2>&1 |sed -r -e 's/^/    /;' |CT_DoLog DEBUG
    else
        CT_DoLog DEBUG "  Not restoring '${dir}': does not exist"
    fi
}

# This function saves the state of the toolchain to be able to restart
# at any one point
# Usage: CT_DoSaveState <next_step_name>
CT_DoSaveState() {
	[ "${CT_DEBUG_CT_SAVE_STEPS}" = "y" ] || return 0
    local state_name="$1"
    local state_dir="${CT_STATE_DIR}/${state_name}"

    # Log this to the log level required by the user
    CT_DoLog ${CT_LOG_LEVEL_MAX} "Saving state to restart at step '${state_name}'..."

    rm -rf "${state_dir}"
    mkdir -p "${state_dir}"

    CT_DoLog DEBUG "  Saving environment and aliases"
    # We must omit shell functions, and some specific bash variables
    # that break when restoring the environment, later. We could do
    # all the processing in the awk script, but a sed is easier...
    set |awk '
              BEGIN { _p = 1; }
              $0~/^[^ ]+ \(\)/ { _p = 0; }
              _p == 1
              $0 == "}" { _p = 1; }
              ' |sed -r -e '/^BASH_(ARGC|ARGV|LINENO|SOURCE|VERSINFO)=/d;
                           /^(UID|EUID)=/d;
                           /^(FUNCNAME|GROUPS|PPID|SHELLOPTS)=/d;' >"${state_dir}/env.sh"

    if [ "${CT_COMPLIBS_BACKUP}" = "y" ]; then
        CT_DoTarballIfExists "${CT_COMPLIBS_DIR}" "${state_dir}/complibs_dir"
    fi
    CT_DoTarballIfExists "${CT_CONFIG_DIR}" "${state_dir}/config_dir"
    CT_DoTarballIfExists "${CT_CC_CORE_STATIC_PREFIX_DIR}" "${state_dir}/cc_core_static_prefix_dir"
    CT_DoTarballIfExists "${CT_CC_CORE_SHARED_PREFIX_DIR}" "${state_dir}/cc_core_shared_prefix_dir"
    CT_DoTarballIfExists "${CT_PREFIX_DIR}" "${state_dir}/prefix_dir" --exclude '*.log'

    if [ "${CT_LOG_TO_FILE}" = "y" ]; then
        CT_DoLog DEBUG "  Saving log file"
        exec >/dev/null
        case "${CT_DEBUG_CT_SAVE_STEPS_GZIP}" in
            y)  gzip -3 -c "${CT_LOG_FILE}"  >"${state_dir}/log.gz";;
            *)  cat "${CT_LOG_FILE}" >"${state_dir}/log";;
        esac
        exec >>"${CT_LOG_FILE}"
    fi
}

# This function restores a previously saved state
# Usage: CT_DoLoadState <state_name>
CT_DoLoadState(){
    local state_name="$1"
    local state_dir="${CT_STATE_DIR}/${state_name}"
    local old_RESTART="${CT_RESTART}"
    local old_STOP="${CT_STOP}"

    CT_TestOrAbort "The previous build did not reach the point where it could be restarted at '${CT_RESTART}'" -d "${state_dir}"

    # We need to do something special with the log file!
    if [ "${CT_LOG_TO_FILE}" = "y" ]; then
        exec >"${state_dir}/tail.log"
    fi

    # Log this to the log level required by the user
    CT_DoLog ${CT_LOG_LEVEL_MAX} "Restoring state at step '${state_name}', as requested."

    CT_DoExtractTarballIfExists "${state_dir}/prefix_dir" "${CT_PREFIX_DIR}"
    CT_DoExtractTarballIfExists "${state_dir}/cc_core_shared_prefix_dir" "${CT_CC_CORE_SHARED_PREFIX_DIR}"
    CT_DoExtractTarballIfExists "${state_dir}/cc_core_static_prefix_dir" "${CT_CC_CORE_STATIC_PREFIX_DIR}"
    CT_DoExtractTarballIfExists "${state_dir}/config_dir" "${CT_CONFIG_DIR}"
    if [ "${CT_COMPLIBS_BACKUP}" = "y" ]; then
        CT_DoExtractTarballIfExists "${state_dir}/complibs_dir" "${CT_COMPLIBS_DIR}"
    fi

    # Restore the environment, discarding any error message
    # (for example, read-only bash internals)
    CT_DoLog DEBUG "  Restoring environment"
    . "${state_dir}/env.sh" >/dev/null 2>&1 || true

    # Restore the new RESTART and STOP steps
    CT_RESTART="${old_RESTART}"
    CT_STOP="${old_STOP}"
    unset old_stop old_restart

    if [ "${CT_LOG_TO_FILE}" = "y" ]; then
        CT_DoLog DEBUG "  Restoring log file"
        exec >/dev/null
        case "${CT_DEBUG_CT_SAVE_STEPS_GZIP}" in
            y)  zcat "${state_dir}/log.gz" >"${CT_LOG_FILE}";;
            *)  cat "${state_dir}/log" >"${CT_LOG_FILE}";;
        esac
        cat "${state_dir}/tail.log" >>"${CT_LOG_FILE}"
        exec >>"${CT_LOG_FILE}"
        rm -f "${state_dir}/tail.log"
    fi
}