[master] 278d90f Update the documentation for obj.hits to reflect code reality.

[Poul-Henning Kamp]

commit 278d90fdc0008a55405550482ccf9bc4d74f18dc
Author: Poul-Henning Kamp <phk at FreeBSD.org>
Date:   Mon May 5 07:00:56 2014 +0000

    Update the documentation for obj.hits to reflect code reality.
    
    In 4.x we changed obj.hits to be read-only, and to count all variants
    under the same hash-key (= same objhdr).
    
    Since we cannot trivially tell if a ban hits all Vary: values or
    just some of them, there is no sane heuristic to fiddle obj.hits
    on bans that would Do The Right Thing.
    
    Fixes #1492

diff --git a/bin/varnishtest/tests/v00039.vtc b/bin/varnishtest/tests/v00039.vtc
new file mode 100644
index 0000000..90bc865
--- /dev/null
+++ b/bin/varnishtest/tests/v00039.vtc
@@ -0,0 +1,58 @@
+varnishtest "obj.hits vs Vary"
+
+server s1 {
+	rxreq
+	txresp -hdr "Vary: bar" -body "foobar"
+	rxreq
+	txresp -hdr "Vary: bar" -body "barf"
+} -start
+
+varnish v1 \
+	-arg "-p ban_lurker_sleep=0.01" \
+	-arg "-p ban_lurker_age=0.01" \
+	-vcl+backend {
+		sub vcl_deliver {
+			set resp.http.hits = obj.hits;
+		}
+	} -start
+
+client c1 {
+	# This is a miss -> hits == 0
+	txreq -url "/" -hdr "Bar: 1"
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 6
+	expect resp.http.hits == 0
+
+	# This is a hit -> hits == 1
+	txreq -url "/" -hdr "Bar: 1"
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 6
+	expect resp.http.hits == 1
+
+	# This is a miss on different vary -> hits still == 1
+	txreq -url "/" -hdr "Bar: 2"
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 4
+	expect resp.http.hits == 1
+
+	# This is a hit -> hits == 2
+	txreq -url "/" -hdr "Bar: 2"
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 4
+	expect resp.http.hits == 2
+
+} -run
+
+# Ban everything on this hash-key
+varnish v1 -cliok "ban obj.http.vary ~ ."
+delay 1
+
+# And run the entire test again to see that obj.hits got reset.
+
+server s1 -start
+
+client c1 -run
diff --git a/lib/libvcc/generate.py b/lib/libvcc/generate.py
index 57f22ca..1e523f1 100755
--- a/lib/libvcc/generate.py
+++ b/lib/libvcc/generate.py
@@ -511,9 +511,12 @@ sp_variables = [
 		'INT',
 		( 'hit', 'deliver',),
 		( ), """
-		The approximate number of times the object has been
-		delivered. A value of 0 indicates a cache miss.
-		This variable is also available in vcl_deliver.
+		The count of cache-hits on this hash-key since it was
+		last instantiated.  This counts cache-hits across all
+		Vary:-ants on this hash-key.
+		The counter will only be reset to zero if/when all objects
+		with this hash-key have disappeared from cache.
+		NB: obj.hits == 0 does *not* indicate a cache miss.
 		"""
 	),
 	('obj.http.',