1 files changed, 172 insertions, 0 deletions
diff --git a/src/encoder.c b/src/encoder.c
new file mode 100644
index 0000000..4b7ad27
--- /dev/null
+++ b/src/encoder.c
@@ -0,0 +1,172 @@
+/*
+ * Author Jerry Lundström <jerry@dns-oarc.net>
+ * Copyright (c) 2019, OARC, Inc.
+ * All rights reserved.
+ *
+ * This file is part of the dnswire library.
+ *
+ * dnswire library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * dnswire library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with dnswire library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "dnswire/encoder.h"
+#include "dnswire/trace.h"
+
+#include <assert.h>
+
+const char* const dnswire_encoder_state_string[] = {
+    "control_ready",
+    "control_start",
+    "control_accept",
+    "control_finish",
+    "frames",
+    "control_stop",
+    "done",
+};
+
+#define __state(h, s)                                                                                     \
+    __trace("state %s => %s", dnswire_encoder_state_string[(h)->state], dnswire_encoder_state_string[s]); \
+    (h)->state = s;
+
+static struct tinyframe_control_field _content_type = {
+    TINYFRAME_CONTROL_FIELD_CONTENT_TYPE,
+    DNSTAP_PROTOBUF_CONTENT_TYPE_LENGTH,
+    (uint8_t*)DNSTAP_PROTOBUF_CONTENT_TYPE,
+};
+
+enum dnswire_result dnswire_encoder_encode(struct dnswire_encoder* handle, uint8_t* out, size_t len)
+{
+    assert(handle);
+    assert(out);
+    assert(len);
+
+    switch (handle->state) {
+    case dnswire_encoder_control_ready:
+        switch (tinyframe_write_control(&handle->writer, out, len, TINYFRAME_CONTROL_READY, &_content_type, 1)) {
+        case tinyframe_ok:
+            __state(handle, dnswire_encoder_control_start);
+            return dnswire_again;
+
+        case tinyframe_need_more:
+            return dnswire_need_more;
+
+        default:
+            break;
+        }
+        return dnswire_error;
+
+    case dnswire_encoder_control_start:
+        switch (tinyframe_write_control_start(&handle->writer, out, len, DNSTAP_PROTOBUF_CONTENT_TYPE, DNSTAP_PROTOBUF_CONTENT_TYPE_LENGTH)) {
+        case tinyframe_ok:
+            __state(handle, dnswire_encoder_frames);
+            return dnswire_again;
+
+        case tinyframe_need_more:
+            return dnswire_need_more;
+
+        default:
+            break;
+        }
+        return dnswire_error;
+
+    case dnswire_encoder_control_accept:
+        switch (tinyframe_write_control(&handle->writer, out, len, TINYFRAME_CONTROL_ACCEPT, &_content_type, 1)) {
+        case tinyframe_ok:
+            __state(handle, dnswire_encoder_control_finish);
+            return dnswire_again;
+
+        case tinyframe_need_more:
+            return dnswire_need_more;
+
+        default:
+            break;
+        }
+        return dnswire_error;
+
+    case dnswire_encoder_control_finish:
+        switch (tinyframe_write_control(&handle->writer, out, len, TINYFRAME_CONTROL_FINISH, 0, 0)) {
+        case tinyframe_ok:
+            __state(handle, dnswire_encoder_done);
+            return dnswire_endofdata;
+
+        case tinyframe_need_more:
+            return dnswire_need_more;
+
+        default:
+            break;
+        }
+        return dnswire_error;
+
+    case dnswire_encoder_frames: {
+        if (!handle->dnstap) {
+            return dnswire_error;
+        }
+
+        size_t frame_len = dnstap_encode_protobuf_size(handle->dnstap);
+        if (len < tinyframe_frame_size(frame_len)) {
+            return dnswire_need_more;
+        }
+        uint8_t frame[frame_len];
+        dnstap_encode_protobuf(handle->dnstap, frame);
+
+        switch (tinyframe_write_frame(&handle->writer, out, len, frame, sizeof(frame))) {
+        case tinyframe_ok:
+            return dnswire_ok;
+
+        case tinyframe_need_more:
+            return dnswire_need_more;
+
+        default:
+            break;
+        }
+        return dnswire_error;
+    }
+
+    case dnswire_encoder_control_stop:
+        switch (tinyframe_write_control_stop(&handle->writer, out, len)) {
+        case tinyframe_ok:
+            __state(handle, dnswire_encoder_done);
+            return dnswire_endofdata;
+
+        case tinyframe_need_more:
+            return dnswire_need_more;
+
+        default:
+            break;
+        }
+        return dnswire_error;
+
+    case dnswire_encoder_done:
+        break;
+    }
+
+    return dnswire_error;
+}
+
+enum dnswire_result dnswire_encoder_stop(struct dnswire_encoder* handle)
+{
+    assert(handle);
+
+    switch (handle->state) {
+    case dnswire_encoder_frames:
+        __state(handle, dnswire_encoder_control_stop);
+        return dnswire_ok;
+
+    default:
+        break;
+    }
+
+    return dnswire_error;
+}