Merge branch 'master' into compile-server2

Author: Zachary Crockett

src/coap.cpp

@@ -32,6 +32,7 @@ CoAPCode::Enum CoAP::code(const unsigned char *message)
     case 0x01: return CoAPCode::GET;
     case 0x02: return CoAPCode::POST;
     case 0x03: return CoAPCode::PUT;
+    case 0x45: return CoAPCode::CONTENT;
     default: return CoAPCode::ERROR;
   }
 }
@@ -47,3 +48,31 @@ CoAPType::Enum CoAP::type(const unsigned char *message)
     case 0x30: return CoAPType::RESET;
   }
 }
+
+size_t CoAP::option_decode(unsigned char **option)
+{
+  unsigned char nibble = **option & 0x0f;
+  size_t option_length;
+  if (13 > nibble)
+  {
+    option_length = nibble;
+    (*option)++;
+  }
+  else if (13 == nibble)
+  {
+    (*option)++;
+    option_length = **option + 13;
+    (*option)++;
+  }
+  else if (14 == nibble)
+  {
+    option_length = ((*(*option + 1) << 8) | *(*option + 2)) + 269;
+    (*option) += 3;
+  }
+  else
+  {
+    // 15 == nibble, reserved value in CoAP spec
+    option_length = 0;
+  }
+  return option_length;
+}

src/coap.h

@@ -22,6 +22,9 @@
   License along with this library; if not, see <http://www.gnu.org/licenses/>.
   ******************************************************************************
   */
+
+#include <string.h>
+
 namespace CoAPMessageType {
   enum Enum {
     HELLO,
@@ -31,9 +34,11 @@ namespace CoAPMessageType {
     UPDATE_BEGIN,
     UPDATE_DONE,
     CHUNK,
+    EVENT,
     KEY_CHANGE,
     SIGNAL_START,
     SIGNAL_STOP,
+    TIME,
     EMPTY_ACK,
     PING,
     ERROR
@@ -46,6 +51,7 @@ namespace CoAPCode {
     POST,
     PUT,
     EMPTY,
+    CONTENT,
     ERROR
   };
 }
@@ -64,4 +70,5 @@ class CoAP
   public:
     static CoAPCode::Enum code(const unsigned char *message);
     static CoAPType::Enum type(const unsigned char *message);
+    static size_t option_decode(unsigned char **option);
 };

src/events.cpp

@@ -33,7 +33,7 @@ size_t event(uint8_t buf[], uint16_t message_id, const char *event_name,
   *p++ = 0x02; // code 0.02 POST request
   *p++ = message_id >> 8;
   *p++ = message_id & 0xff;
-  *p++ = 0xb1;
+  *p++ = 0xb1; // one-byte Uri-Path option
   *p++ = event_type;
 
   size_t name_data_len = strnlen(event_name, 63);
@@ -59,9 +59,74 @@ size_t event(uint8_t buf[], uint16_t message_id, const char *event_name,
   return p - buf;
 }
 
+// Private, used by two subscription variants below
+uint8_t *subscription_prelude(uint8_t buf[], uint16_t message_id,
+                              const char *event_name)
+{
+  uint8_t *p = buf;
+  *p++ = 0x40; // confirmable, no token
+  *p++ = 0x01; // code 0.01 GET request
+  *p++ = message_id >> 8;
+  *p++ = message_id & 0xff;
+  *p++ = 0xb1; // one-byte Uri-Path option
+  *p++ = 'e';
+
+  if (NULL != event_name)
+  {
+    size_t len = strnlen(event_name, 63);
+    p += event_name_uri_path(p, event_name, len);
+  }
+
+  return p;
+}
+
+size_t subscription(uint8_t buf[], uint16_t message_id,
+                    const char *event_name, const char *device_id)
+{
+  uint8_t *p = subscription_prelude(buf, message_id, event_name);
+
+  if (NULL != device_id)
+  {
+    size_t len = strnlen(device_id, 63);
+
+    *p++ = 0xff;
+    memcpy(p, device_id, len);
+    p += len;
+  }
+
+  return p - buf;
+}
+
+size_t subscription(uint8_t buf[], uint16_t message_id,
+                    const char *event_name, SubscriptionScope::Enum scope)
+{
+  uint8_t *p = subscription_prelude(buf, message_id, event_name);
+
+  switch (scope)
+  {
+    case SubscriptionScope::MY_DEVICES:
+      *p++ = 0x41; // one-byte Uri-Query option
+      *p++ = 'u';
+      break;
+    case SubscriptionScope::FIREHOSE:
+    default:
+      // unfiltered firehose is not allowed
+      if (NULL == event_name || 0 == *event_name)
+      {
+        return -1;
+      }
+  }
+
+  return p - buf;
+}
+
 size_t event_name_uri_path(uint8_t buf[], const char *name, size_t name_len)
 {
-  if (name_len < 13)
+  if (0 == name_len)
+  {
+    return 0;
+  }
+  else if (name_len < 13)
   {
     buf[0] = name_len;
     memcpy(buf + 1, name, name_len);

src/events.h

@@ -35,9 +35,30 @@ namespace EventType {
   };
 }
 
+namespace SubscriptionScope {
+  enum Enum {
+    MY_DEVICES,
+    FIREHOSE
+  };
+}
+
+typedef void (*EventHandler)(const char *event_name, const char *data);
+
+struct FilteringEventHandler
+{
+  char filter[64];
+  EventHandler handler;
+};
+
 size_t event(uint8_t buf[], uint16_t message_id, const char *event_name,
              const char *data, int ttl, EventType::Enum event_type);
 
+size_t subscription(uint8_t buf[], uint16_t message_id,
+                    const char *event_name, const char *device_id);
+
+size_t subscription(uint8_t buf[], uint16_t message_id,
+                    const char *event_name, SubscriptionScope::Enum scope);
+
 size_t event_name_uri_path(uint8_t buf[], const char *name, size_t name_len);
 
 #endif // __EVENTS_H