Adding upstream version 5.6.0.upstream/5.6.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 291 insertions, 0 deletions

diff --git a/lib/rplan.c b/lib/rplan.c
new file mode 100644
index 0000000..0bedd8a
--- /dev/null
+++ b/lib/rplan.c
@@ -0,0 +1,291 @@
+/*  Copyright (C) CZ.NIC, z.s.p.o. <knot-resolver@labs.nic.cz>
+ *  SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include <libknot/descriptor.h>
+#include <libknot/errcode.h>
+
+#include "lib/rplan.h"
+#include "lib/resolve.h"
+
+#define VERBOSE_MSG(qry, ...) kr_log_q(qry, PLAN,  __VA_ARGS__)
+
+inline static unsigned char chars_or(const unsigned char a, const unsigned char b)
+{
+	return a | b;
+}
+
+/** Bits set to 1 in variable b will be set to zero in variable a. */
+inline static unsigned char chars_mask(const unsigned char a, const unsigned char b)
+{
+	return a & ~b;
+}
+
+/** Apply mod(a, b) to every byte a, b from fl1, fl2 and return result in fl1. */
+inline static void kr_qflags_mod(struct kr_qflags *fl1, struct kr_qflags fl2,
+			unsigned char mod(const unsigned char a, const unsigned char b))
+{
+	kr_require(fl1);
+	union {
+		struct kr_qflags flags;
+		/* C99 section 6.5.3.4: sizeof(char) == 1 */
+		unsigned char chars[sizeof(struct kr_qflags)];
+	} tmp1, tmp2;
+	/* The compiler should be able to optimize all this into simple ORs. */
+	tmp1.flags = *fl1;
+	tmp2.flags = fl2;
+	for (size_t i = 0; i < sizeof(struct kr_qflags); ++i) {
+		tmp1.chars[i] = mod(tmp1.chars[i], tmp2.chars[i]);
+	}
+	*fl1 = tmp1.flags;
+}
+
+/**
+ * Set bits from variable fl2 in variable fl1.
+ * Bits which are not set in fl2 are not modified in fl1.
+ *
+ * @param[in,out] fl1
+ * @param[in] fl2
+ */
+void kr_qflags_set(struct kr_qflags *fl1, struct kr_qflags fl2)
+{
+	kr_qflags_mod(fl1, fl2, chars_or);
+}
+
+/**
+ * Clear bits from variable fl2 in variable fl1.
+ * Bits which are not set in fl2 are not modified in fl1.
+ *
+ * @param[in,out] fl1
+ * @param[in] fl2
+ */
+void kr_qflags_clear(struct kr_qflags *fl1, struct kr_qflags fl2)
+{
+	kr_qflags_mod(fl1, fl2, chars_mask);
+}
+
+static struct kr_query *query_create(knot_mm_t *pool, const knot_dname_t *name, uint32_t uid)
+{
+	struct kr_query *qry = mm_calloc(pool, 1, sizeof(*qry));
+	if (qry == NULL) {
+		return NULL;
+	}
+
+	if (name != NULL) {
+		qry->sname = knot_dname_copy(name, pool);
+		if (qry->sname == NULL) {
+			mm_free(pool, qry);
+			return NULL;
+		}
+	}
+
+	knot_dname_to_lower(qry->sname);
+	qry->uid = uid;
+	return qry;
+}
+
+static void query_free(knot_mm_t *pool, struct kr_query *qry)
+{
+	kr_zonecut_deinit(&qry->zone_cut);
+	mm_free(pool, qry->sname);
+	mm_free(pool, qry);
+}
+
+int kr_rplan_init(struct kr_rplan *rplan, struct kr_request *request, knot_mm_t *pool)
+{
+	if (rplan == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	memset(rplan, 0, sizeof(struct kr_rplan));
+
+	rplan->pool = pool;
+	rplan->request = request;
+	array_init(rplan->pending);
+	array_init(rplan->resolved);
+	rplan->next_uid = 0;
+	return KNOT_EOK;
+}
+
+void kr_rplan_deinit(struct kr_rplan *rplan)
+{
+	if (rplan == NULL) {
+		return;
+	}
+
+	for (size_t i = 0; i < rplan->pending.len; ++i) {
+		query_free(rplan->pool, rplan->pending.at[i]);
+	}
+	for (size_t i = 0; i < rplan->resolved.len; ++i) {
+		query_free(rplan->pool, rplan->resolved.at[i]);
+	}
+	array_clear_mm(rplan->pending, mm_free, rplan->pool);
+	array_clear_mm(rplan->resolved, mm_free, rplan->pool);
+}
+
+bool kr_rplan_empty(struct kr_rplan *rplan)
+{
+	if (rplan == NULL) {
+		return true;
+	}
+
+	return rplan->pending.len == 0;
+}
+
+static struct kr_query *kr_rplan_push_query(struct kr_rplan *rplan,
+                                            struct kr_query *parent,
+                                            const knot_dname_t *name)
+{
+	if (rplan == NULL) {
+		return NULL;
+	}
+
+	/* Make sure there's enough space */
+	int ret = array_reserve_mm(rplan->pending, rplan->pending.len + 1, kr_memreserve, rplan->pool);
+	if (ret != 0) {
+		return NULL;
+	}
+
+	struct kr_query *qry = query_create(rplan->pool, name, rplan->next_uid);
+	if (qry == NULL) {
+		return NULL;
+	}
+	rplan->next_uid += 1;
+	/* Class and type must be set outside this function. */
+	qry->flags = rplan->request->options;
+	qry->parent = parent;
+	qry->request = rplan->request;
+
+	gettimeofday(&qry->timestamp, NULL);
+	qry->timestamp_mono = kr_now();
+	qry->creation_time_mono = parent ? parent->creation_time_mono : qry->timestamp_mono;
+	kr_zonecut_init(&qry->zone_cut, (const uint8_t *)"", rplan->pool);
+	qry->reorder = qry->flags.REORDER_RR ? kr_rand_bytes(sizeof(qry->reorder)) : 0;
+
+
+	kr_assert((rplan->pending.len == 0 && rplan->resolved.len == 0)
+			 == (rplan->initial == NULL));
+	if (rplan->initial == NULL) {
+		rplan->initial = qry;
+	}
+
+	array_push(rplan->pending, qry);
+
+	return qry;
+}
+
+struct kr_query *kr_rplan_push_empty(struct kr_rplan *rplan, struct kr_query *parent)
+{
+	if (rplan == NULL) {
+		return NULL;
+	}
+
+	struct kr_query *qry = kr_rplan_push_query(rplan, parent, NULL);
+	if (qry == NULL) {
+		return NULL;
+	}
+
+	VERBOSE_MSG(qry, "plan '%s' type '%s'  uid [%05u.%02u]\n", "", "",
+		    qry->request ? qry->request->uid : 0, qry->uid);
+	return qry;
+}
+
+struct kr_query *kr_rplan_push(struct kr_rplan *rplan, struct kr_query *parent,
+                               const knot_dname_t *name, uint16_t cls, uint16_t type)
+{
+	if (rplan == NULL || name == NULL) {
+		return NULL;
+	}
+
+	struct kr_query *qry = kr_rplan_push_query(rplan, parent, name);
+	if (qry == NULL) {
+		return NULL;
+	}
+
+	qry->sclass = cls;
+	qry->stype = type;
+
+	if (kr_log_is_debug_qry(PLAN, qry)) {
+		KR_DNAME_GET_STR(name_str, name);
+		KR_RRTYPE_GET_STR(type_str, type);
+		VERBOSE_MSG(parent, "plan '%s' type '%s' uid [%05u.%02u]\n",
+			    name_str, type_str,
+			    qry->request ? qry->request->uid : 0, qry->uid);
+	}
+	return qry;
+}
+
+int kr_rplan_pop(struct kr_rplan *rplan, struct kr_query *qry)
+{
+	if (rplan == NULL || qry == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	/* Make sure there's enough space */
+	int ret = array_reserve_mm(rplan->resolved, rplan->resolved.len + 1, kr_memreserve, rplan->pool);
+	if (ret != 0) {
+		return ret;
+	}
+
+	/* Find the query, it will likely be on top */
+	for (size_t i = rplan->pending.len; i > 0; i--) {
+		if (rplan->pending.at[i - 1] == qry) {
+			/* Delete i-1 element by *sliding* the rest,
+			 * contrary to array_del() */
+			for (size_t j = i; j < rplan->pending.len; ++j)
+				rplan->pending.at[j - 1] = rplan->pending.at[j];
+			array_pop(rplan->pending);
+
+			array_push(rplan->resolved, qry);
+			break;
+		}
+	}
+	return KNOT_EOK;
+}
+
+bool kr_rplan_satisfies(struct kr_query *closure, const knot_dname_t *name, uint16_t cls, uint16_t type)
+{
+	while (name && closure) {
+		if (closure->sclass == cls && closure->stype == type
+		    && knot_dname_is_equal(closure->sname, name)) {
+			return true;
+		}
+		closure = closure->parent;
+	}
+	return false;
+}
+
+struct kr_query *kr_rplan_resolved(struct kr_rplan *rplan)
+{
+	if (rplan->resolved.len == 0) {
+		return NULL;
+	}
+	return array_tail(rplan->resolved);
+}
+
+struct kr_query *kr_rplan_last(struct kr_rplan *rplan)
+{
+	if (!kr_rplan_empty(rplan)) {
+		return array_tail(rplan->pending);
+	}
+
+	return kr_rplan_resolved(rplan);
+}
+
+struct kr_query *kr_rplan_find_resolved(struct kr_rplan *rplan, struct kr_query *parent,
+                               const knot_dname_t *name, uint16_t cls, uint16_t type)
+{
+	struct kr_query *ret = NULL;
+	for (int i = 0; i < rplan->resolved.len; ++i) {
+		struct kr_query *q = rplan->resolved.at[i];
+		if (q->stype == type && q->sclass == cls &&
+		    (parent == NULL || q->parent == parent) &&
+		    knot_dname_is_equal(q->sname, name)) {
+			ret = q;
+			break;
+		}
+	}
+	return ret;
+}
+
+#undef VERBOSE_MSG