configure

#!/bin/bash 

# defaults
prefix=/usr/local
VERSION="0.6.0"
ERRORS=0

# Parse Arguments
Usage()
{
    echo "$0 [options]"
    echo ""
    echo "Options:"
    echo "  --help|-h       Print this usage note."
    echo "  --prefix|-p     Insallation prefix."
}

while :
do
    case $1 in
        -h | --help)
            Usage
            exit 0
            ;;
        -p | --prefix)
            file=$2     # You might want to check if you really got FILE
            shift 2
            ;;
        --prefix=*)
            prefix=${1#*=}        # Delete everything up till "="
            shift
            ;;
        -*)
            echo "unknown option: $1" >&2
            echo ""
            Usage
            exit 0
            ;;
        *)  # no more options. Stop while loop
            break
            ;;
    esac
done

# test

# 1: the rest running
echo_test()
{
    printf "%-40s" "$1"
}

# 1: result to display
echo_result()
{
    printf "%10s\n" "$1"
}

# 1: command to check
check_tool()
{
    echo_test "checking for $1 "
    if command -v $1  >/dev/null 2>&1; then 
        echo_result "yes"
    else    
        echo_result "no"
        ERRORS=1
    fi
}

# 1: name
# 2: module signature
check_pkg_module()
{
    echo_test "checking for $2 "
    if pkg-config "$2" --modversion >/dev/null 2>&1; then
        echo_result "`pkg-config "$2" --modversion`"
        export $1_CFLAGS="`pkg-config --cflags "$2"`"
        export $1_LIBS="`pkg-config --libs "$2"`"
    else
        echo_result "no"
        ERRORS=1
    fi
}

# 1: header
# 2: compiler flags
check_header_c()
{
    echo_test "checking for header $1 "
    echo "#include <$1>" > conftest.c
    if gcc -c conftest.c $CFLAGS $2 >/dev/null 2>&1; then
        echo_result "yes"
    else
        echo_result "no"
        ERRORS=1
    fi
    rm -f conftest.c conftest.o
}

# 1: lib to check
# 2: compiler flags
# 3: linker flags
check_lib_c()
{
    echo_test "checking for library $1 "
    echo "int main(int argc, char* argv[]) { }" >> conftest.c
    if gcc conftest.c $CFLAGS -l$1 $2 $3 $LDFLAGS -o conftest.exe >/dev/null 2>&1; then
        echo_result "yes"
    else
        echo_result "no"
        ERRORS=1
    fi
    rm -f conftest.c conftest.exe
}

# 1: variable to hold result
# 2: libs to check for
# 3: compiler flags
# 4: linker flags
check_libs_c()
{
    local LIBS=$2
    local FOUND=0
    for LIB in $LIBS; do
        echo_test "checking for library $LIB "
        echo "int main(int argc, char* argv[]) { }" >> conftest.c
        if gcc conftest.c $CFLAGS -l$LIB $3 $4 $LDFLAGS -o conftest.exe >/dev/null 2>&1; then
            echo_result "yes"
            export $1=$LIB
            FOUND=1
            break 
        else
            echo_result "no"            
        fi
        rm -f conftest.c conftest.exe
    done
    
    if test $FOUND = 0; then
        ERRORS=1
    fi
}

# actual checks

check_tool "g++"
check_tool "make"
check_tool "pkg-config"

check_pkg_module "XML2" "libxml-2.0 >= 2.9.0" 

#output

export_variable()
{
    echo $1=${!1} >> config.mk
}

if test $ERRORS = 0; then
    rm -f config.mk
    
    echo ""
    echo "Writing config.mk"
    echo "CONFIG_MK_INCLUDED = 1" >> config.mk    
    echo "prefix ?= $prefix" >> config.mk      
    export_variable VERSION
    export_variable XML2_CFLAGS
    export_variable XML2_LIBS

    echo "Writing libxmlmm.pc"
    prefix_e=`echo "$prefix" | sed -e 's/[]\\\/()$*.^|[]/\\\\&/g'`   
    VERSION_e=`echo "$VERSION" | sed -e 's/[]\\\/()$*.^|[]/\\\\&/g'`   
    sed -e "s/@prefix@/$prefix_e/g" -e "s/@VERSION@/$VERSION_e/g"  libxmlmm.pc.in > libxmlmm.pc
    
    echo ""
    echo "Everything OK."
    echo ""
else
    echo ""
    echo "There where errors. Check output."
    echo ""
fi