Move output parameters to end and add defines for buffer sizes

wrappers/libnimbus.h

@@ -50,6 +50,12 @@ typedef struct {
 
 typedef void (*received_msg_handler)(received_message* msg, void* udata);
 
+/** Buffer lengths, can be used in go for convenience */
+#define ID_LEN 32
+#define SYMKEY_LEN 32
+#define PRIVKEY_LEN 32
+#define BLOOM_LEN 64
+
 /** Initialize Nim and the Status library. Must be called before anything else
  * of the API. Also, all following calls must come from the same thread as from
  * which this call was done.
@@ -77,19 +83,20 @@ void nimbus_poll();
 
 /** Raw 32 byte arrays are passed as IDs. The caller needs to provide a pointer
  * to 32 bytes allocation for this. */
-bool nimbus_new_keypair(uint8_t id[32]);
-bool nimbus_add_keypair(uint8_t id[32], const uint8_t privkey[32]);
-bool nimbus_delete_keypair(const uint8_t id[32]);
-bool nimbus_get_private_key(const uint8_t id[32], uint8_t privkey[32]);
+bool nimbus_new_keypair(uint8_t id[ID_LEN]);
+bool nimbus_add_keypair(const uint8_t privkey[PRIVKEY_LEN], uint8_t id[ID_LEN]);
+bool nimbus_delete_keypair(const uint8_t id[ID_LEN]);
+bool nimbus_get_private_key(const uint8_t id[ID_LEN],
+  uint8_t privkey[PRIVKEY_LEN]);
 
 /** Symmetric Keys API */
 
 /** Raw 32 byte arrays are passed as IDs. The caller needs to provide a pointer
  * to 32 bytes allocation for this. */
-bool nimbus_add_symkey(uint8_t id[32], const uint8_t symkey[32]);
-bool nimbus_add_symkey_from_password(uint8_t id[32], const char* password);
-bool nimbus_delete_symkey(const uint8_t id[32]);
-bool nimbus_get_symkey(const uint8_t id[32], uint8_t symkey[32]);
+bool nimbus_add_symkey(const uint8_t symkey[SYMKEY_LEN], uint8_t id[ID_LEN]);
+bool nimbus_add_symkey_from_password(const char* password, uint8_t id[ID_LEN]);
+bool nimbus_delete_symkey(const uint8_t id[ID_LEN]);
+bool nimbus_get_symkey(const uint8_t id[ID_LEN], uint8_t symkey[SYMKEY_LEN]);
 
 /** Whisper message posting and receiving API */
 
@@ -98,9 +105,9 @@ bool nimbus_post(post_message* msg);
 /** Subscribe to given filter. The void pointer udata will be passed to the
  * received_msg_handler callback.
  */
-bool nimbus_subscribe_filter(uint8_t id[32], filter_options* filter_options,
-  received_msg_handler msg, void* udata);
-bool nimbus_unsubscribe_filter(const uint8_t id[32]);
+bool nimbus_subscribe_filter(filter_options* filter_options,
+  received_msg_handler msg, void* udata, uint8_t id[ID_LEN]);
+bool nimbus_unsubscribe_filter(const uint8_t id[ID_LEN]);
 
 /** Get the minimum required PoW of this node */
 double nimbus_get_min_pow();
@@ -108,7 +115,7 @@ double nimbus_get_min_pow();
 /** Get the currently set bloom filter of this node. This will automatically
  *update for each filter subsribed to.
  */
-void nimbus_get_bloom_filter(uint8_t bloomfilter[64]);
+void nimbus_get_bloom_filter(uint8_t bloomfilter[BLOOM_LEN]);
 
 /** Example helper, can be removed */
 topic nimbus_channel_to_topic(const char* channel);

wrappers/libnimbus.nim

@@ -176,7 +176,7 @@ proc nimbus_new_keypair(id: var Identifier): bool {.exportc, raises: [].} =
     # in `newKeyPair`
     discard
 
-proc nimbus_add_keypair(id: var Identifier, privateKey: ptr byte):
+proc nimbus_add_keypair(privateKey: ptr byte, id: var Identifier):
     bool {.exportc, raises: [OSError, IOError, ValueError].} =
   ## Caller needs to provide as id a pointer to 32 bytes allocation.
   doAssert(not (unsafeAddr id).isNil, "Key id cannot be nil.")
@@ -213,7 +213,7 @@ proc nimbus_get_private_key(id: Identifier, privateKey: var PrivateKey):
 
 # Symmetric Keys
 
-proc nimbus_add_symkey(id: var Identifier, symKey: ptr SymKey): bool
+proc nimbus_add_symkey(symKey: ptr SymKey, id: var Identifier): bool
     {.exportc, raises: [].} =
   ## Caller needs to provide as id a pointer to 32 bytes allocation.
   doAssert(not (unsafeAddr id).isNil, "Key id cannot be nil.")
@@ -225,7 +225,7 @@ proc nimbus_add_symkey(id: var Identifier, symKey: ptr SymKey): bool
   # Copy of key happens at add
   whisperKeys.symKeys.add(id.toHex, symKey[])
 
-proc nimbus_add_symkey_from_password(id: var Identifier, password: cstring):
+proc nimbus_add_symkey_from_password(password: cstring, id: var Identifier):
     bool {.exportc, raises: [].} =
   ## Caller needs to provide as id a pointer to 32 bytes allocation.
   doAssert(not (unsafeAddr id).isNil, "Key id cannot be nil.")
@@ -321,9 +321,9 @@ proc nimbus_post(message: ptr CPostMessage): bool {.exportc.} =
                             powTime = message.powTime,
                             powTarget = message.powTarget)
 
-proc nimbus_subscribe_filter(id: var Identifier, options: ptr CFilterOptions,
+proc nimbus_subscribe_filter(options: ptr CFilterOptions,
     handler: proc (msg: ptr CReceivedMessage, udata: pointer) {.gcsafe, cdecl.},
-    udata: pointer = nil): bool {.exportc.} =
+    udata: pointer = nil, id: var Identifier): bool {.exportc.} =
   ## Encryption is mandatory.
   ## A symmetric key or an asymmetric key must be provided. Both is not allowed.
   ## In case of a passed handler, the received msg needs to be copied before the

wrappers/wrapper_whisper_example.go

@@ -60,25 +60,24 @@ func StatusListenAndPost(channel string) {
 	channelC := C.CString(channel)
 	defer C.free(unsafe.Pointer(channelC))
 
-	tmp := C.malloc(C.size_t(32))
-	if C.nimbus_add_symkey_from_password((*C.uint8_t)(tmp), channelC) == false {
+	tmp := C.malloc(C.size_t(C.ID_LEN))
+	if C.nimbus_add_symkey_from_password(channelC, (*C.uint8_t)(tmp)) == false {
 		panic("Cannot create symmetric key")
 	}
 	// No need to do this back and forth GO <-> C, just showing how it might work
 	// in implementations (when wrapped in calls passing Go Bytes or Strings).
-	symKeyId := C.GoBytes(tmp, 32)
+	symKeyId := C.GoBytes(tmp, C.ID_LEN)
 	C.free(unsafe.Pointer(tmp))
 	symKeyIdC := (*C.uint8_t)(C.CBytes(symKeyId))
 	defer C.free(unsafe.Pointer(symKeyIdC))
 
-
-	tmp = C.malloc(C.size_t(32))
+	tmp = C.malloc(C.size_t(C.ID_LEN))
 	if C.nimbus_new_keypair((*C.uint8_t)(tmp)) == false {
 		panic("Cannot create asymmetric keypair")
 	}
 	// No need to do this back and forth GO <-> C, just showing how it might work
 	// in implementations (when wrapped in calls passing Go Bytes or Strings).
-	asymKeyId := C.GoBytes(tmp, 32)
+	asymKeyId := C.GoBytes(tmp, C.ID_LEN)
 	C.free(unsafe.Pointer(tmp))
 	asymKeyIdC := (*C.uint8_t)(C.CBytes(asymKeyId))
 	defer C.free(unsafe.Pointer(asymKeyIdC))
@@ -89,13 +88,13 @@ func StatusListenAndPost(channel string) {
 		minPow: 0.002,
 		topic: C.nimbus_channel_to_topic(channelC).topic}
 
-	tmp = C.malloc(C.size_t(32))
-	if C.nimbus_subscribe_filter((*C.uint8_t)(tmp), &options,
+	tmp = C.malloc(C.size_t(C.ID_LEN))
+	if C.nimbus_subscribe_filter(&options,
 			(C.received_msg_handler)(unsafe.Pointer(C.receiveHandler_cgo)),
-			unsafe.Pointer(&msgCount)) == false {
+			unsafe.Pointer(&msgCount), (*C.uint8_t)(tmp)) == false {
 		panic("Cannot subscribe filter")
 	}
-	filterId := C.GoBytes(tmp, 32)
+	filterId := C.GoBytes(tmp, C.ID_LEN)
 	C.free(unsafe.Pointer(tmp))
 	fmt.Printf("[nim-status] filter subscribed, id: %s\n",
 		hex.EncodeToString(filterId))