lib/resolve: use begin layer for resolution start

this provides a useful callback for per-request operations that can’t wait until the query is completed (e.g. blocking or logging started queries)

diff --git a/lib/layer/iterate.c b/lib/layer/iterate.c
index fb4e38c6a58b3e39a5914c6a88067bc1b680ee37..8ca1f8054228f5acde901f263a1be2c46007a6e2 100644 (file)
--- a/lib/layer/iterate.c
+++ b/lib/layer/iterate.c
@@ -351,7 +351,9 @@ static int finish(knot_layer_t *ctx) { return KNOT_STATE_NOOP; }
 /* Set resolution context and parameters. */
 static int begin(knot_layer_t *ctx, void *module_param)
 {
-       ctx->data = module_param;
+       if (ctx->state & (KNOT_STATE_DONE|KNOT_STATE_FAIL)) {
+               return ctx->state;
+       }
        return reset(ctx);
 }
 

diff --git a/lib/layer/pktcache.c b/lib/layer/pktcache.c
index eb62571cb84f0899956cbbaff83d2bc880d8b1d2..0193772f902cf6a2addf78f90f0941b9625c5ad1 100644 (file)
--- a/lib/layer/pktcache.c
+++ b/lib/layer/pktcache.c
@@ -31,12 +31,6 @@ static inline uint8_t get_tag(knot_pkt_t *pkt)
        return knot_pkt_has_dnssec(pkt) ? KR_CACHE_SEC : KR_CACHE_PKT;
 }
 
-static int begin(knot_layer_t *ctx, void *module_param)
-{
-       ctx->data = module_param;
-       return ctx->state;
-}
-
 static uint32_t limit_ttl(uint32_t ttl)
 {
        /* @todo Configurable limit */
@@ -217,7 +211,6 @@ static int stash(knot_layer_t *ctx, knot_pkt_t *pkt)
 const knot_layer_api_t *pktcache_layer(struct kr_module *module)
 {
        static const knot_layer_api_t _layer = {
-               .begin   = &begin,
                .produce = &peek,
                .consume  = &stash
        };

diff --git a/lib/layer/rrcache.c b/lib/layer/rrcache.c
index 9d017caf64d2a1d17c44e3acc921406e253d7272..1025d434ed2f171245e91eac8ab7403c6eabe648 100644 (file)
--- a/lib/layer/rrcache.c
+++ b/lib/layer/rrcache.c
@@ -28,12 +28,6 @@
 #define DEBUG_MSG(fmt...) QRDEBUG(kr_rplan_current(rplan), " rc ",  fmt)
 #define DEFAULT_MINTTL (5) /* Short-time "no data" retention to avoid bursts */
 
-static int begin(knot_layer_t *ctx, void *module_param)
-{
-       ctx->data = module_param;
-       return ctx->state;
-}
-
 /** Record is expiring if it has less than 1% TTL (or less than 5s) */
 static inline bool is_expiring(const knot_rrset_t *rr, uint32_t drift)
 {
@@ -312,7 +306,6 @@ static int stash(knot_layer_t *ctx, knot_pkt_t *pkt)
 const knot_layer_api_t *rrcache_layer(struct kr_module *module)
 {
        static const knot_layer_api_t _layer = {
-               .begin = &begin,
                .produce = &peek,
                .consume = &stash
        };

diff --git a/lib/resolve.c b/lib/resolve.c
index 75f0d7bb40bf5f5767dbd05bf409ec5d49e8d5c8..919b74c4dc7d17c63892f6ab827676e55db55b08 100644 (file)
--- a/lib/resolve.c
+++ b/lib/resolve.c
@@ -32,9 +32,11 @@
 #define ITERATE_LAYERS(req, func, ...) \
        for (unsigned i = 0; i < (req)->ctx->modules->len; ++i) { \
                struct kr_module *mod = (req)->ctx->modules->at[i]; \
-               if (mod->layer) { \
+               if (mod->layer ) { \
                        struct knot_layer layer = {.state = (req)->state, .api = mod->layer(mod), .data = (req)}; \
-                       (req)->state = (func)(&layer, ##__VA_ARGS__); \
+                       if (layer.api && layer.api->func) { \
+                               (req)->state = layer.api->func(&layer, ##__VA_ARGS__); \
+                       } \
                } \
        }
 
@@ -368,7 +370,8 @@ int kr_resolve_query(struct kr_request *request, const knot_dname_t *qname, uint
        knot_wire_set_rcode(answer->wire, KNOT_RCODE_NOERROR);
 
        /* Expect answer */
-       return KNOT_STATE_PRODUCE;
+       ITERATE_LAYERS(request, begin, request);
+       return request->state;
 }
 
 int kr_resolve_consume(struct kr_request *request, knot_pkt_t *packet)
@@ -404,7 +407,7 @@ int kr_resolve_consume(struct kr_request *request, knot_pkt_t *packet)
                if (qname_raw && qry->secret != 0) {
                        randomized_qname_case(qname_raw, qry->secret);
                }
-               ITERATE_LAYERS(request, knot_layer_consume, packet);
+               ITERATE_LAYERS(request, consume, packet);
        }
 
        /* Resolution failed, invalidate current NS. */
@@ -427,7 +430,7 @@ int kr_resolve_consume(struct kr_request *request, knot_pkt_t *packet)
                qry->flags &= ~(QUERY_CACHED|QUERY_TCP);
        }
 
-       ITERATE_LAYERS(request, knot_layer_reset);
+       ITERATE_LAYERS(request, reset);
        return kr_rplan_empty(&request->rplan) ? KNOT_STATE_DONE : KNOT_STATE_PRODUCE;
 }
 
@@ -450,12 +453,12 @@ int kr_resolve_produce(struct kr_request *request, struct sockaddr **dst, int *t
 #endif
 
        /* Resolve current query and produce dependent or finish */
-       ITERATE_LAYERS(request, knot_layer_produce, packet);
+       ITERATE_LAYERS(request, produce, packet);
        if (request->state != KNOT_STATE_FAIL && knot_wire_get_qr(packet->wire)) {
                /* Produced an answer, consume it. */
                qry->secret = 0;
                request->state = KNOT_STATE_CONSUME;
-               ITERATE_LAYERS(request, knot_layer_consume, packet);
+               ITERATE_LAYERS(request, consume, packet);
        }
        switch(request->state) {
        case KNOT_STATE_FAIL: return request->state; break;
@@ -465,7 +468,7 @@ int kr_resolve_produce(struct kr_request *request, struct sockaddr **dst, int *t
                if (qry->flags & QUERY_RESOLVED) {
                        kr_rplan_pop(rplan, qry);
                }
-               ITERATE_LAYERS(request, knot_layer_reset);
+               ITERATE_LAYERS(request, reset);
                return kr_rplan_empty(rplan) ? KNOT_STATE_DONE : KNOT_STATE_PRODUCE;
        }
 
@@ -498,7 +501,7 @@ ns_election:
                kr_nsrep_elect(qry, request->ctx);
                if (qry->ns.score > KR_NS_MAX_SCORE) {
                        DEBUG_MSG("=> no valid NS left\n");
-                       ITERATE_LAYERS(request, knot_layer_reset);
+                       ITERATE_LAYERS(request, reset);
                        kr_rplan_pop(rplan, qry);
                        return KNOT_STATE_PRODUCE;
                }
@@ -510,7 +513,7 @@ ns_election:
                        qry->flags &= ~(QUERY_AWAIT_IPV6|QUERY_AWAIT_IPV4|QUERY_TCP);
                        goto ns_election; /* Must try different NS */
                }
-               ITERATE_LAYERS(request, knot_layer_reset);
+               ITERATE_LAYERS(request, reset);
                return KNOT_STATE_PRODUCE;
        }
 
@@ -552,7 +555,7 @@ int kr_resolve_finish(struct kr_request *request, int state)
                        knot_wire_set_rcode(answer->wire, KNOT_RCODE_SERVFAIL);
                }
        }
-       ITERATE_LAYERS(request, knot_layer_finish);
+       ITERATE_LAYERS(request, finish);
        /* Clean up. */
        kr_rplan_deinit(&request->rplan);
        return KNOT_STATE_DONE;

diff --git a/modules/stats/stats.c b/modules/stats/stats.c
index 81263984c970c33976e2a127ad1eeebf743beaa5..7b747101db11a06ecff78bb18df7d09b4f4c95c1 100644 (file)
--- a/modules/stats/stats.c
+++ b/modules/stats/stats.c
@@ -89,12 +89,6 @@ static inline void stat_const_add(struct stat_data *data, enum const_metric key,
        const_metrics[key].val += incr;
 }
 
-static int begin(knot_layer_t *ctx, void *module_param)
-{
-       ctx->data = module_param;
-       return ctx->state;
-}
-
 static int collect_answer(struct stat_data *data, knot_pkt_t *pkt)
 {
        stat_const_add(data, metric_answer_total, 1);
@@ -341,7 +335,6 @@ static char* clear_expiring(void *env, struct kr_module *module, const char *arg
 const knot_layer_api_t *stats_layer(struct kr_module *module)
 {
        static knot_layer_api_t _layer = {
-               .begin = &begin,
                .finish = &collect,
        };
        /* Store module reference */