def populate_lic_qa_checksum(d):
    """
    Check for changes in the license files.
    """
    import tempfile
    sane = True

    lic_files = d.getVar('LIC_FILES_CHKSUM') or ''
    lic = d.getVar('LICENSE')
    pn = d.getVar('PN')

    if lic == "CLOSED":
        return

    if not lic_files and d.getVar('SRC_URI'):
        sane = package_qa_handle_error("license-checksum", pn + ": Recipe file fetches files and does not have license file information (LIC_FILES_CHKSUM)", d)

    srcdir = d.getVar('S')
    corebase_licensefile = d.getVar('COREBASE') + "/LICENSE"
    for url in lic_files.split():
        try:
            (type, host, path, user, pswd, parm) = bb.fetch.decodeurl(url)
        except bb.fetch.MalformedUrl:
            sane = package_qa_handle_error("license-checksum", pn + ": LIC_FILES_CHKSUM contains an invalid URL: " + url, d)
            continue
        srclicfile = os.path.join(srcdir, path)
        if not os.path.isfile(srclicfile):
            package_qa_handle_error("license-checksum", pn + ": LIC_FILES_CHKSUM points to an invalid file: " + srclicfile, d)
            continue

        if (srclicfile == corebase_licensefile):
            bb.warn("${COREBASE}/LICENSE is not a valid license file, please use '${COMMON_LICENSE_DIR}/MIT' for a MIT License file in LIC_FILES_CHKSUM. This will become an error in the future")

        recipemd5 = parm.get('md5', '')
        beginline, endline = 0, 0
        if 'beginline' in parm:
            beginline = int(parm['beginline'])
        if 'endline' in parm:
            endline = int(parm['endline'])

        if (not beginline) and (not endline):
            md5chksum = bb.utils.md5_file(srclicfile)
            with open(srclicfile, 'rb') as f:
                license = f.read()
        else:
            fi = open(srclicfile, 'rb')
            fo = tempfile.NamedTemporaryFile(mode='wb', prefix='poky.', suffix='.tmp', delete=False)
            tmplicfile = fo.name;
            lineno = 0
            linesout = 0
            license = []
            for line in fi:
                lineno += 1
                if (lineno >= beginline):
                    if ((lineno <= endline) or not endline):
                        fo.write(line)
                        license.append(line)
                        linesout += 1
                    else:
                        break
            fo.flush()
            fo.close()
            fi.close()
            md5chksum = bb.utils.md5_file(tmplicfile)
            license = b''.join(license)
            os.unlink(tmplicfile)

        if recipemd5 == md5chksum:
            bb.note (pn + ": md5 checksum matched for ", url)
        else:
            if recipemd5:
                msg = pn + ": The LIC_FILES_CHKSUM does not match for " + url
                msg = msg + "\n" + pn + ": The new md5 checksum is " + md5chksum
                try:
                    license_lines = license.decode('utf-8').split('\n')
                except:
                    # License text might not be valid UTF-8, in which
                    # case we don't know how to include it in our output
                    # and have to skip it.
                    pass
                else:
                    max_lines = int(d.getVar('QA_MAX_LICENSE_LINES') or 20)
                    if not license_lines or license_lines[-1] != '':
                        # Ensure that our license text ends with a line break
                        # (will be added with join() below).
                        license_lines.append('')
                    remove = len(license_lines) - max_lines
                    if remove > 0:
                        start = max_lines // 2
                        end = start + remove - 1
                        del license_lines[start:end]
                        license_lines.insert(start, '...')
                    msg = msg + "\n" + pn + ": Here is the selected license text:" + \
                          "\n" + \
                          "{:v^70}".format(" beginline=%d " % beginline if beginline else "") + \
                          "\n" + "\n".join(license_lines) + \
                          "{:^^70}".format(" endline=%d " % endline if endline else "")
                if beginline:
                    if endline:
                        srcfiledesc = "%s (lines %d through to %d)" % (srclicfile, beginline, endline)
                    else:
                        srcfiledesc = "%s (beginning on line %d)" % (srclicfile, beginline)
                elif endline:
                    srcfiledesc = "%s (ending on line %d)" % (srclicfile, endline)
                else:
                    srcfiledesc = srclicfile
                msg = msg + "\n" + pn + ": Check if the license information has changed in %s to verify that the LICENSE value \"%s\" remains valid" % (srcfiledesc, lic)

            else:
                msg = pn + ": LIC_FILES_CHKSUM is not specified for " +  url
                msg = msg + "\n" + pn + ": The md5 checksum is " + md5chksum
            sane = package_qa_handle_error("license-checksum", msg, d)

    if not sane:
        bb.fatal("Fatal QA errors found, failing task.")

populate_lic_qa_checksum(d)

def package_qa_handle_error(error_class, error_msg, d):
    if error_class in (d.getVar("ERROR_QA") or "").split():
        package_qa_write_error(error_class, error_msg, d)
        bb.error("QA Issue: %s [%s]" % (error_msg, error_class))
        d.setVar("QA_SANE", False)
        return False
    elif error_class in (d.getVar("WARN_QA") or "").split():
        package_qa_write_error(error_class, error_msg, d)
        bb.warn("QA Issue: %s [%s]" % (error_msg, error_class))
    else:
        bb.note("QA Issue: %s [%s]" % (error_msg, error_class))
    return True

def package_qa_write_error(type, error, d):
    logfile = d.getVar('QA_LOGFILE')
    if logfile:
        p = d.getVar('P')
        with open(logfile, "a+") as f:
            f.write("%s: %s [%s]\n" % (p, error, type))