New RPM provides for the varnishd and VMODs

The find-provides script takes the original script and forwards almost
all lines to the original find-provides command provided by RPM. In
order for this to work, %global needs to be used instead of %define to
ensure immediate expansion and avoid infinite recursion.

VMODs are not forwared to find-provides because it matters little to
advertise them as shared objects in the traditional sense.

The output looks like this:

    vmod(blob)
    vmod(directors)
    vmod(purge)
    vmod(std)
    vmod(vtc)
    varnishd(abi) = <sha1>
    varnishd(vrt) = x.y

Partially fixes #8 because in order to make this useful for VMODs
without forcing package maintainers to manually require either the
exact ABI or a given VRT version, a means for automatic requires
for VMOD builds is missing. This doesn't address the NOGIT case,
but we don't support packaging not originating from a git commit.

This would make #92 obsolete once something similar is done on the
DPKG side.

redhat/find-provides

-#!/bin/bash
+#!/bin/sh
+#
 # This script is used to inject the Varnish ABI into the RPM Provides.
 
-set -o errexit
+#set -e
 
-if [ -x /usr/lib/rpm/redhat/find-provides ]; then
-    /usr/lib/rpm/redhat/find-provides "$@"
-elif [ -x /usr/lib/rpm/find-provides ]; then
-    /usr/lib/rpm/find-provides "$@"
-fi
+BUILD_DIR=$(dirname "$0")
+FIND_PROVIDES="$1"
+shift
 
-# We don't install vcs_version.h, so we can't use RPM_BUILD_ROOT directly.
-cd /builddir/build/BUILD/varnish* || true
-cd ${RPM_BUILD_ROOT}/../../BUILD/varnish* || true
+expand_macro() {
+	cpp - -Iinclude <<-EOF |
+	#include "vcs_version.h"
+	#include "vdef.h"
+	#include "vrt.h"
+	$1
+	EOF
+	tail -1
+}
 
-printf '#include "vcs_version.h"\nVCS_Version\n' \
-        | cpp - -Iinclude | sed -e '/^"/!d' -e 's/\"//g' -e 's/^/varnishabi-strict-/'
+varnishd_provides() (
+	cd "$BUILD_DIR"
 
-printf '#include "vrt.h"\nvarnishabi- VRT_MAJOR_VERSION . VRT_MINOR_VERSION\n' \
-	| cpp - -Iinclude \
-	| sed -e '/^varnishabi-/!d' -e 's/U//g' -e 's/ //g'
+	ABI=$(expand_macro VCS_Version | tr -d '"')
+	VRT_MAJOR=$(expand_macro VRT_MAJOR_VERSION | tr -c -d '[0-9]')
+	VRT_MINOR=$(expand_macro VRT_MINOR_VERSION | tr -c -d '[0-9]')
+
+	cat <<-EOF
+	varnishd(abi) = $ABI
+	varnishd(vrt) = $VRT_MAJOR.$VRT_MINOR
+	EOF
+)
+
+while read -r FILE
+do
+	case $FILE in
+	*bin/varnishd)
+		varnishd_provides
+		printf "%s\n" "$FILE" | $FIND_PROVIDES "$@"
+		;;
+	*/libvmod_*.so)
+		VMOD=${FILE##*/libvmod_}
+		VMOD=${VMOD%.so}
+		printf 'vmod(%s)\n' "$VMOD"
+		;;
+	*)
+		printf "%s\n" "$FILE" | $FIND_PROVIDES "$@"
+		;;
+	esac
+done

redhat/varnish.spec

-%define vd_rc %{?v_rc:-%{?v_rc}}
+%global vd_rc %{?v_rc:-%{?v_rc}}
 
-%define _use_internal_dependency_generator 0
-%define __find_provides %{_builddir}/%{srcname}/find-provides
+%global _use_internal_dependency_generator 0
+%global __find_provides %{_builddir}/%{srcname}/find-provides %__find_provides
 
-%define debug_package %{nil}
+%global debug_package %{nil}
 
 
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