add a script to update waf; it will come in handy now and in the future

waf-update.sh

@@ -0,0 +1,94 @@
+#/bin/sh
+# This script eases updating the waf build system. Make sure wget and gpg are
+# installed and run:
+# $ ./waf-update.sh <version>
+# This script will deploy the build system in source form as to ease downtream
+# maintainence at Debian/Ubuntu. For example see [1] and the pages it links to.
+# [1] https://wiki.debian.org/UnpackWaf
+
+script=`basename ${0}`
+
+msg() {
+    echo "${script}: ${@}"
+}
+
+die() {
+    msg "${@}"
+    exit 1
+}
+
+test $# -ne 1 && die "usage: ${script} <version>"
+version=${1}
+
+homepage=https://waf.io
+
+# Fetch the pubkey from the main homepage.
+pubkey=tnagy1024.asc
+if ! test -e ${pubkey}
+then
+    wget ${homepage}/${pubkey} || die "wget failed"
+fi
+
+# The key can also be found at freehackers.
+pubkey2=${pubkey}.2
+if ! test -e ${pubkey2}
+then
+    wget http://freehackers.org/~tnagy/${pubkey} -O ${pubkey2} || die "wget failed"
+fi
+
+# Make sure the keys are identic.
+cmp ${pubkey} ${pubkey2}
+status=$?
+if test $status -eq 0
+then
+    msg "${pubkey} and ${pubkey2} match"
+elif test $status -eq 1
+then
+    die "${pubkey} and ${pubkey2} did not match"
+else
+    die "cmp failed"
+fi
+
+# Now that the keys match, it is likely that this key is the real key so import
+# it.
+gpg --import ${pubkey} || die "could not import public key"
+
+waf_dir=waf-${version}
+waf_tar=${waf_dir}.tar.bz2
+waf_asc=${waf_tar}.asc
+
+if ! test -e ${waf_tar}
+then
+    wget ${homepage}/${waf_tar} || die "wget failed"
+fi
+
+if ! test -e ${waf_asc}
+then
+    wget ${homepage}/${waf_asc} || die "wget failed"
+fi
+
+gpg --verify ${waf_asc}
+if test $? -eq 0
+then
+    msg "tarball verification succeeded"
+else
+    die "tarball verificatin failed"
+fi
+
+if test -d ${waf_dir}
+then
+    rm -rf ${waf_dir} || die "could not remove old waf directory"
+fi
+
+tar xjf ${waf_tar} || die "could not unpack tarball"
+
+# Remove the old waflib directory and replace it with the new.
+git rm -rf waflib || die "could not remove old waflib directory"
+cp -R ${waf_dir}/waflib . || die "could not copy waflib directory"
+git add waflib || die "could not add waflib to version control"
+
+# Copy the waf-light script to the toplevel directory and rename it to waf so
+# that the usual ./waf [args] can be used.
+cp ${waf_dir}/waf-light waf || die "could not copy waf-light"
+
+exit 0