From 4daaaaf4a7707e290af6e7fc23e8e03fde946a74 Mon Sep 17 00:00:00 2001
From: "Roger A. Light" <roger@atchoo.org>
Date: Tue, 16 Oct 2018 14:35:37 +0100
Subject: [PATCH] Add property writing support, untested.

---
 lib/packet_datatypes.c | 24 +++++++++++++
 lib/packet_mosq.h      |  1 +
 lib/property_mosq.c    | 81 ++++++++++++++++++++++++++++++++++++++++--
 lib/property_mosq.h    |  2 +-
 4 files changed, 105 insertions(+), 3 deletions(-)

diff --git a/lib/packet_datatypes.c b/lib/packet_datatypes.c
index dd15d673..a07a9f54 100644
--- a/lib/packet_datatypes.c
+++ b/lib/packet_datatypes.c
@@ -225,3 +225,27 @@ int packet__read_varint(struct mosquitto__packet *packet, int32_t *word, int8_t
 	return MOSQ_ERR_PROTOCOL;
 }
 
+
+int packet__write_varint(struct mosquitto__packet *packet, int32_t word)
+{
+	uint8_t byte;
+	int count = 0;
+
+	packet->payload = NULL;
+	packet->remaining_count = 0;
+	do{
+		byte = word % 128;
+		word = word / 128;
+		/* If there are more digits to encode, set the top bit of this digit */
+		if(word > 0){
+			byte = byte | 0x80;
+		}
+		packet__write_byte(packet, byte);
+		count++;
+	}while(word > 0 && count < 5);
+
+	if(count == 5){
+		return MOSQ_ERR_PROTOCOL;
+	}
+	return MOSQ_ERR_SUCCESS;
+}
diff --git a/lib/packet_mosq.h b/lib/packet_mosq.h
index 8c44d6ab..04855327 100644
--- a/lib/packet_mosq.h
+++ b/lib/packet_mosq.h
@@ -40,6 +40,7 @@ void packet__write_bytes(struct mosquitto__packet *packet, const void *bytes, ui
 void packet__write_string(struct mosquitto__packet *packet, const char *str, uint16_t length);
 void packet__write_uint16(struct mosquitto__packet *packet, uint16_t word);
 void packet__write_uint32(struct mosquitto__packet *packet, uint32_t word);
+int packet__write_varint(struct mosquitto__packet *packet, int32_t word);
 
 int packet__write(struct mosquitto *mosq);
 #ifdef WITH_BROKER
diff --git a/lib/property_mosq.c b/lib/property_mosq.c
index 74fbd662..5bb7331a 100644
--- a/lib/property_mosq.c
+++ b/lib/property_mosq.c
@@ -358,9 +358,86 @@ int property__get_length_all(struct mqtt5__property *property)
 }
 
 
-int property__write_all(struct mosquitto__packet *packet, struct mqtt5__property **property)
+int property__write(struct mosquitto__packet *packet, struct mqtt5__property *property)
 {
-	packet__write_byte(packet, 0);
+	int rc;
+
+	rc = packet__write_varint(packet, property->identifier);
+	if(rc) return rc;
+
+	switch(property->identifier){
+		case PROP_PAYLOAD_FORMAT_INDICATOR:
+		case PROP_REQUEST_PROBLEM_INFO:
+		case PROP_REQUEST_RESPONSE_INFO:
+		case PROP_MAXIMUM_QOS:
+		case PROP_RETAIN_AVAILABLE:
+		case PROP_WILDCARD_SUB_AVAILABLE:
+		case PROP_SUBSCRIPTION_ID_AVAILABLE:
+		case PROP_SHARED_SUB_AVAILABLE:
+			packet__write_byte(packet, property->value.i8);
+			break;
+
+		case PROP_SERVER_KEEP_ALIVE:
+		case PROP_RECEIVE_MAXIMUM:
+		case PROP_TOPIC_ALIAS_MAXIMUM:
+		case PROP_TOPIC_ALIAS:
+			packet__write_uint16(packet, property->value.i16);
+			break;
+
+		case PROP_MESSAGE_EXPIRY_INTERVAL:
+		case PROP_SESSION_EXPIRY_INTERVAL:
+		case PROP_WILL_DELAY_INTERVAL:
+		case PROP_MAXIMUM_PACKET_SIZE:
+			packet__write_uint32(packet, property->value.i32);
+			break;
+
+		case PROP_SUBSCRIPTION_IDENTIFIER:
+			return packet__write_varint(packet, property->value.varint);
+
+		case PROP_CONTENT_TYPE:
+		case PROP_RESPONSE_TOPIC:
+		case PROP_ASSIGNED_CLIENT_IDENTIFIER:
+		case PROP_AUTHENTICATION_METHOD:
+		case PROP_RESPONSE_INFO:
+		case PROP_SERVER_REFERENCE:
+		case PROP_REASON_STRING:
+			packet__write_string(packet, property->value.s.v, property->value.s.len);
+			break;
+
+		case PROP_AUTHENTICATION_DATA:
+		case PROP_CORRELATION_DATA:
+			packet__write_uint16(packet, property->value.bin.len);
+			packet__write_bytes(packet, property->value.bin.v, property->value.bin.len);
+
+		case PROP_USER_PROPERTY:
+			packet__write_string(packet, property->name.v, property->name.len);
+			packet__write_string(packet, property->value.s.v, property->value.s.len);
+			break;
+
+		default:
+			log__printf(NULL, MOSQ_LOG_DEBUG, "Unsupported property type: %d", property->identifier);
+			return MOSQ_ERR_INVAL;
+	}
+
+	return MOSQ_ERR_SUCCESS;
+}
+
+
+int property__write_all(struct mosquitto__packet *packet, struct mqtt5__property *properties)
+{
+	int rc;
+	struct mqtt5__property *p;
+
+	rc = packet__write_varint(packet, property__get_length_all(properties));
+	if(rc) return rc;
+
+	p = properties;
+	while(p){
+		rc = property__write(packet, p);
+		if(rc) return rc;
+		p = p->next;
+	}
+
 	return MOSQ_ERR_SUCCESS;
 }
 
diff --git a/lib/property_mosq.h b/lib/property_mosq.h
index 7f7ea548..9e913f99 100644
--- a/lib/property_mosq.h
+++ b/lib/property_mosq.h
@@ -40,7 +40,7 @@ struct mqtt5__property {
 
 
 int property__read_all(struct mosquitto__packet *packet, struct mqtt5__property **property);
-int property__write_all(struct mosquitto__packet *packet, struct mqtt5__property **property);
+int property__write_all(struct mosquitto__packet *packet, struct mqtt5__property *property);
 void property__free(struct mqtt5__property **property);
 void property__free_all(struct mqtt5__property **property);