Merge r4146: Add if-none-match support

Add if-none-match support to allow people with compliant browsers to
save a decent chunk of bandwidth


git-svn-id: http://www.varnish-cache.org/svn/branches/2.0@4294 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache_response.c

@@ -56,8 +56,10 @@ res_do_304(struct sess *sp)
 	http_PrintfHeader(sp->wrk, sp->fd, sp->http, "Date: %s", lm);
 	http_SetHeader(sp->wrk, sp->fd, sp->http, "Via: 1.1 varnish");
 	http_PrintfHeader(sp->wrk, sp->fd, sp->http, "X-Varnish: %u", sp->xid);
-	TIM_format(sp->obj->last_modified, lm);
-	http_PrintfHeader(sp->wrk, sp->fd, sp->http, "Last-Modified: %s", lm);
+	if (sp->obj->last_modified) {
+		TIM_format(sp->obj->last_modified, lm);
+		http_PrintfHeader(sp->wrk, sp->fd, sp->http, "Last-Modified: %s", lm);
+	}
 	http_PrintfHeader(sp->wrk, sp->fd, sp->http, "Connection: %s",
 	    sp->doclose ? "close" : "keep-alive");
 	sp->wantbody = 0;
@@ -68,17 +70,33 @@ res_do_304(struct sess *sp)
 static int
 res_do_conds(struct sess *sp)
 {
-	char *p;
+	char *p, *e;
 	double ims;
+	int do_cond = 0;
+
+	/* RFC 2616 13.3.4 states we need to match both ETag
+	   and If-Modified-Since if present*/
 
-	if (sp->obj->last_modified > 0 &&
-	    http_GetHdr(sp->http, H_If_Modified_Since, &p)) {
+	if (http_GetHdr(sp->http, H_If_Modified_Since, &p) ) {
+		if (!sp->obj->last_modified)
+			return (0);
 		ims = TIM_parse(p);
 		if (ims > sp->t_req)	/* [RFC2616 14.25] */
 			return (0);
 		if (sp->obj->last_modified > ims) {
 			return (0);
 		}
+		do_cond = 1;
+	}
+
+	if (http_GetHdr(sp->http, H_If_None_Match, &p) &&
+	    http_GetHdr(sp->obj->http, H_ETag, &e)) {
+		if (strcmp(p,e) != 0)
+			return (0);
+		do_cond = 1;
+	}
+
+	if (do_cond == 1) { 
 		res_do_304(sp);
 		return (1);
 	}

bin/varnishtest/tests/c00025.vtc

+# $Id$
+
+test "Test If-None-Match"
+
+server s1 {
+	rxreq
+	expect req.url == "/foo"
+	txresp -hdr "ETag: 123456789" \
+	    -body "11111\n"
+} -start
+
+varnish v1 -vcl+backend { } -start
+
+client c1 {
+	txreq -url "/foo"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.content-length == 6
+
+	txreq -url "/foo" \
+	    -hdr "If-None-Match: 12345678"
+	rxresp
+	expect resp.status == 200
+
+	txreq -url "/foo" \
+	    -hdr "If-None-Match: 123456789"
+	rxresp
+	expect resp.status == 304
+} 
+
+client c1 -run
+
+client c1 -run

bin/varnishtest/tests/c00026.vtc

+# $Id$
+
+test "Test Combination of If-None-Match and If-Modified-Since"
+
+server s1 {
+	rxreq
+	expect req.url == "/foo"
+	txresp -hdr "ETag: 123456789" \
+	       -hdr "Last-Modified: Thu, 26 Jun 2008 12:00:01 GMT" \
+	    -body "11111\n"
+} -start
+
+varnish v1 -vcl+backend { } -start
+
+client c1 {
+	txreq -url "/foo"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.content-length == 6
+
+	txreq -url "/foo" \
+	    -hdr "If-None-Match: 123456789"
+	rxresp
+	expect resp.status == 304
+
+	txreq -url "/foo" \
+	    -hdr "If-Modified-Since: Thu, 26 Jun 2008 12:00:01 GMT"
+	rxresp
+	expect resp.status == 304
+
+	txreq -url "/foo" \
+	    -hdr "If-Modified-Since: Thu, 26 Jun 2008 12:00:00 GMT" \
+	    -hdr "If-None-Match: 123456789"
+	rxresp
+	expect resp.status == 200
+
+	txreq -url "/foo" \
+	    -hdr "If-Modified-Since: Thu, 26 Jun 2008 12:00:01 GMT" \
+	    -hdr "If-None-Match: 12345678"
+	rxresp
+	expect resp.status == 200
+
+	txreq -url "/foo" \
+	    -hdr "If-Modified-Since: Thu, 26 Jun 2008 12:00:01 GMT" \
+	    -hdr "If-None-Match: 123456789"
+	rxresp
+	expect resp.status == 304
+
+} 
+
+client c1 -run
+
+client c1 -run