[PATCH 01/10] Maintain an offset into the persisted ban list pointing to the first non-dropped ban.

[Martin Blix Grydeland]

---
 bin/varnishd/storage/storage_persistent.c |   37 +++++++++++++++++++++++++++++
 bin/varnishd/storage/storage_persistent.h |    1 +
 2 files changed, 38 insertions(+)

diff --git a/bin/varnishd/storage/storage_persistent.c b/bin/varnishd/storage/storage_persistent.c
index 5f756b7..f5398b9 100644
--- a/bin/varnishd/storage/storage_persistent.c
+++ b/bin/varnishd/storage/storage_persistent.c
@@ -90,6 +90,37 @@ smp_appendban(struct smp_sc *sc, struct smp_signspace *spc,
 	smp_append_signspace(spc, ptr - ptr2);
 }
 
+/*--------------------------------------------------------------------
+ * Update *offset with the offset of the first ban record past ban
+ */
+
+static void
+smp_offset_banlist(struct smp_sc *sc, struct smp_signspace *spc,
+		   uint64_t *offset, const uint8_t *ban, unsigned ln)
+{
+	uint8_t *ptr, *ptr2;
+	uint32_t len;
+
+	(void)sc;
+	ptr = ptr2 = (uint8_t *)SIGNSPACE_DATA(spc) + *offset;
+	assert(ptr <= (uint8_t *)SIGNSPACE_FRONT(spc));
+
+	while (ptr < (uint8_t *)SIGNSPACE_FRONT(spc)) {
+		AZ(memcmp(ptr, "BAN", 4));
+		ptr += 4;
+
+		len = vbe32dec(ptr);
+		ptr += 4;
+
+		ptr += len;
+
+		if (len == ln && !memcmp(ptr - len, ban, len)) {
+			*offset += ptr - ptr2;
+			return;
+		}
+	}
+}
+
 /* Trust that cache_ban.c takes care of locking */
 
 static void
@@ -106,6 +137,12 @@ smp_baninfo(struct stevedore *stv, enum baninfo event,
 			smp_appendban(sc, &sc->ban2, len, ban);
 		}
 		break;
+	case BI_DROP:
+		VTAILQ_FOREACH(sc, &silos, list) {
+			smp_offset_banlist(sc, &sc->ban1, &sc->ban1_offset,
+					   ban, len);
+		}
+		break;
 	default:
 		/* Ignored */
 		break;
diff --git a/bin/varnishd/storage/storage_persistent.h b/bin/varnishd/storage/storage_persistent.h
index cb2efb3..c2cbac3 100644
--- a/bin/varnishd/storage/storage_persistent.h
+++ b/bin/varnishd/storage/storage_persistent.h
@@ -139,6 +139,7 @@ struct smp_sc {
 	struct smp_signspace	seg2;
 
 	struct ban		*tailban;
+	uint64_t		ban1_offset;
 
 	struct lock		mtx;
 
-- 
1.7.9.5