source: ps/trunk/build/premake/pkgconfig/pkgconfig.lua

local m = {}
m._VERSION = "1.1.2-dev"

m.additional_pc_path = nil
m.static_link_libs = false

local function os_capture(cmd)
    return io.popen(cmd, 'r'):read('*a'):gsub("\n", " ")
end

function m.add_includes(lib, alternative_cmd, alternative_flags)
    local result
    if not alternative_cmd then
        local pc_path = m.additional_pc_path and "PKG_CONFIG_PATH="..m.additional_pc_path or ""
        result = os_capture(pc_path.." pkg-config --cflags "..lib)
    else
        if not alternative_flags then
            result = os_capture(alternative_cmd.." --cflags")
        else
            result = os_capture(alternative_cmd.." "..alternative_flags)
        end
    end

    -- Small trick: delete the space after -include so that we can detect
    -- which files have to be force-included without difficulty.
    result = result:gsub("%-include +(%g+)", "-include%1")

    local dirs = {}
    local files = {}
    local options = {}
    for w in string.gmatch(result, "[^' ']+") do
        if string.sub(w,1,2) == "-I" then
            table.insert(dirs, string.sub(w,3))
        elseif string.sub(w,1,8) == "-include" then
            table.insert(files, string.sub(w,9))
        else
            table.insert(options, w)
        end
    end

    -- As of premake5-beta2, `sysincludedirs` has been deprecated in favour of
    -- `externalincludedirs`, and continuing to use it causes warnings to be emitted.
    -- We use `externalincludedirs` when available to prevent the warnings, falling back
    -- to `sysincludedirs` when not to prevent breakage of the `--with-system-premake5`
    -- build argument.
    if externalincludedirs then
        externalincludedirs(dirs)
    else
        sysincludedirs(dirs)
    end

    forceincludes(files)
    buildoptions(options)
end

function m.add_links(lib, alternative_cmd, alternative_flags)
    local result
    if not alternative_cmd then
        local pc_path = m.additional_pc_path and "PKG_CONFIG_PATH="..m.additional_pc_path or ""
        local static = m.static_link_libs and " --static " or ""
        result = os_capture(pc_path.." pkg-config --libs "..static..lib)
    else
        if not alternative_flags then
            result = os_capture(alternative_cmd.." --libs")
        else
            result = os_capture(alternative_cmd.." "..alternative_flags)
        end
    end

    -- On OSX, wx-config outputs "-framework foo" instead of "-Wl,-framework,foo"
    -- which doesn't fare well with the splitting into libs, libdirs and options
    -- we perform afterwards.
    result = result:gsub("%-framework +(%g+)", "-Wl,-framework,%1")

    local libs = {}
    local dirs = {}
    local options = {}
    for w in string.gmatch(result, "[^' ']+") do
        if string.sub(w,1,2) == "-l" then
            table.insert(libs, string.sub(w,3))
        elseif string.sub(w,1,2) == "-L" then
            table.insert(dirs, string.sub(w,3))
        else
            table.insert(options, w)
        end
    end

    links(libs)
    libdirs(dirs)
    linkoptions(options)
end

return m