Added ZTS_ERR_GENERAL, also minor updates to JNI layer

include/ZeroTierConstants.h

@@ -44,6 +44,8 @@
 #define ZTS_ERR_INVALID_OP                 -3
 // The call succeeded, but no object or relevant result was available
 #define ZTS_ERR_NO_RESULT                  -4
+// General internal failure
+#define ZTS_ERR_GENERAL                    -5
 
 /**
  * The system port upon which ZT traffic is sent and received

src/Controls.cpp

@@ -75,21 +75,15 @@ int _port;
 std::string _path;
 
 /*
- * A lock used to protect any call which relies on the presence of a valid pointer
+ * A lock used to protect any call which relies on the presence of a valid
- * to the ZeroTier service.
+ * pointer to the ZeroTier service.
  */
 Mutex _service_lock;
 
 /*
- * A lock which protects flags and state variables used during the startup and
+ * A lock used to protect callback method pointers. With a coarser-grained
- * shutdown phase.
+ * lock it would be possible for one thread to alter the callback method
- */
+ * pointer causing undefined behaviour.
-Mutex _startup_lock;
-
-/*
- * A lock used to protect callback method pointers. With a coarser-grained lock it
- * would be possible for one thread to alter the callback method pointer causing 
- * undefined behaviour.
  */
 Mutex _callback_lock;
 
@@ -425,13 +419,14 @@ extern "C" {
 
 #ifdef SDK_JNI
 /*
- * Called from Java, saves a static reference to the VM so it can be used later to call
+ * Called from Java, saves a static reference to the VM so it can be used
- * a user-specified callback method from C.
+ * later to call a user-specified callback method from C.
  */
-JNIEXPORT void JNICALL Java_com_zerotier_libzt_ZeroTier_init(JNIEnv *env, jobject thisObj)
+JNIEXPORT int JNICALL Java_com_zerotier_libzt_ZeroTier_init(
+	JNIEnv *env, jobject thisObj)
 {
     jint rs = env->GetJavaVM(&jvm);
-    assert (rs == JNI_OK);
+	return rs != JNI_OK ? ZTS_ERR_GENERAL : ZTS_ERR_OK;
 }
 #endif
 
@@ -515,7 +510,8 @@ int zts_deorbit(uint64_t moonWorldId)
 #ifdef SDK_JNI
 #endif
 
-int zts_start(const char *path, void (*callback)(struct zts_callback_msg*), int port)
+int zts_start(
+	const char *path, void (*callback)(struct zts_callback_msg*), int port)
 {
 	Mutex::Lock _l(_service_lock);
 	lwip_driver_init();
@@ -524,7 +520,8 @@ int zts_start(const char *path, void (*callback)(struct zts_callback_msg*), int
 		return ZTS_ERR_INVALID_OP;
 	}
 	if (_freeHasBeenCalled) {
-		// Stack (presumably lwIP) has been dismantled, an application restart is required now
+		// Stack (presumably lwIP) has been dismantled,
+		// an application restart is required now
 		return ZTS_ERR_INVALID_OP;
 	}
 #ifdef SDK_JNI
@@ -607,10 +604,15 @@ JNIEXPORT int JNICALL Java_com_zerotier_libzt_ZeroTier_start(
 		DEBUG_ERROR("Couldn't find onZeroTierEvent method");
 		return ZTS_ERR_INVALID_ARG;
 	}
-	objRef = env->NewGlobalRef(callback); // Reference used for later calls
+	// Reference used for later calls
+	objRef = env->NewGlobalRef(callback);
 	_userCallbackMethodRef = eventListenerCallbackMethod;
 	const char* utf_string = env->GetStringUTFChars(path, NULL);
-	int retval = zts_start(utf_string, NULL, port); // using _userCallbackMethodRef
+	if (!utf_string) {
+		return ZTS_ERR_GENERAL;
+	}
+	// using _userCallbackMethodRef
+	int retval = zts_start(utf_string, NULL, port);
 	env->ReleaseStringUTFChars(path, utf_string);
 	return retval;
 }

src/Sockets.cpp

@@ -186,7 +186,7 @@ int zts_setsockopt(int fd, int level, int optname, const void *optval, socklen_t
 JNIEXPORT jint JNICALL Java_com_zerotier_libzt_ZeroTier_setsockopt(
 	JNIEnv *env, jobject thisObj, jint fd, jint level, jint optname, jobject optval)
 {
-	jclass c = (*env).GetObjectClass(optval);
+	jclass c = env->GetObjectClass(optval);
 	if (!c) {
 		return ZTS_ERR_INVALID_OP;
 	}
@@ -198,8 +198,8 @@ JNIEXPORT jint JNICALL Java_com_zerotier_libzt_ZeroTier_setsockopt(
 		|| optname == SO_REUSEPORT
 		|| optname == TCP_NODELAY)
 	{
-		jfieldID fid = (*env).GetFieldID(c, "booleanValue", "Z");
+		jfieldID fid = env->GetFieldID(c, "booleanValue", "Z");
-		optval_int = (int)(*env).GetBooleanField(optval, fid);
+		optval_int = (int)(env->GetBooleanField(optval, fid));
 	}
 	if (optname == IP_TTL
 		|| optname == SO_RCVTIMEO
@@ -208,8 +208,8 @@ JNIEXPORT jint JNICALL Java_com_zerotier_libzt_ZeroTier_setsockopt(
 		|| optname == SO_RCVBUF
 		|| optname == SO_SNDBUF)
 	{
-		jfieldID fid = (*env).GetFieldID(c, "integerValue", "I");
+		jfieldID fid = env->GetFieldID(c, "integerValue", "I");
-		optval_int = (*env).GetIntField(optval, fid);
+		optval_int = env->GetIntField(optval, fid);
 	}
 
 	int retval = ZTS_ERR_OK;
@@ -236,7 +236,7 @@ int zts_getsockopt(int fd, int level, int optname, void *optval, socklen_t *optl
 JNIEXPORT jint JNICALL Java_com_zerotier_libzt_ZeroTier_getsockopt(
 	JNIEnv *env, jobject thisObj, jint fd, jint level, jint optname, jobject optval)
 {
-	jclass c = (*env).GetObjectClass(optval);
+	jclass c = env->GetObjectClass(optval);
 	if (!c) {
 		return ZTS_ERR_INVALID_OP;
 	}
@@ -262,10 +262,10 @@ JNIEXPORT jint JNICALL Java_com_zerotier_libzt_ZeroTier_getsockopt(
 		|| optname == SO_REUSEPORT
 		|| optname == TCP_NODELAY)
 	{
-		jfieldID fid = (*env).GetFieldID(c, "isBoolean", "Z");
+		jfieldID fid = env->GetFieldID(c, "isBoolean", "Z");
-		(*env).SetBooleanField(optval, fid, true);
+		env->SetBooleanField(optval, fid, true);
-		fid = (*env).GetFieldID(c, "booleanValue", "Z");
+		fid = env->GetFieldID(c, "booleanValue", "Z");
-		(*env).SetBooleanField(optval, fid, (bool)optval_int);
+		env->SetBooleanField(optval, fid, (bool)optval_int);
 	}
 	if (optname == IP_TTL
 		|| optname == SO_RCVTIMEO
@@ -274,10 +274,10 @@ JNIEXPORT jint JNICALL Java_com_zerotier_libzt_ZeroTier_getsockopt(
 		|| optname == SO_RCVBUF
 		|| optname == SO_SNDBUF)
 	{
-		jfieldID fid = (*env).GetFieldID(c, "isInteger", "Z");
+		jfieldID fid = env->GetFieldID(c, "isInteger", "Z");
-		(*env).SetBooleanField(optval, fid, true);
+		env->SetBooleanField(optval, fid, true);
-		fid = (*env).GetFieldID(c, "integerValue", "I");
+		fid = env->GetFieldID(c, "integerValue", "I");
-		(*env).SetIntField(optval, fid, optval_int);
+		env->SetIntField(optval, fid, optval_int);
 	}
 	return retval > -1 ? retval : -(zts_errno);
 }
@@ -461,12 +461,12 @@ JNIEXPORT int JNICALL Java_com_zerotier_libzt_ZeroTier_ioctl(
 		int bytesRemaining = 0;
 		retval = zts_ioctl(fd, request, &bytesRemaining);	
 		// set value in general object
-		jclass c = (*env).GetObjectClass(argp);
+		jclass c = env->GetObjectClass(argp);
 		if (!c) {
 			return ZTS_ERR_INVALID_ARG;
 		}
-		jfieldID fid = (*env).GetFieldID(c, "integer", "I");
+		jfieldID fid = env->GetFieldID(c, "integer", "I");
-		(*env).SetIntField(argp, fid, bytesRemaining);
+		env->SetIntField(argp, fid, bytesRemaining);
 	}
 	if (request == FIONBIO) {
 		// TODO: double check
@@ -678,40 +678,40 @@ int zts_del_dns_nameserver(struct sockaddr *addr)
 #ifdef SDK_JNI
 void ztfdset2fdset(JNIEnv *env, int nfds, jobject src_ztfd_set, fd_set *dest_fd_set)
 {
-	jclass c = (*env).GetObjectClass(src_ztfd_set);
+	jclass c = env->GetObjectClass(src_ztfd_set);
 	if (!c) {
 		return;
 	}
 	FD_ZERO(dest_fd_set);
 	jfieldID fid = env->GetFieldID(c, "fds_bits", "[B");
-	jobject fdData = (*env).GetObjectField (src_ztfd_set, fid);
+	jobject fdData = env->GetObjectField (src_ztfd_set, fid);
 	jbyteArray * arr = reinterpret_cast<jbyteArray*>(&fdData);
-	char *data = (char*)(*env).GetByteArrayElements(*arr, NULL);	
+	char *data = (char*)env->GetByteArrayElements(*arr, NULL);
 	for (int i=0; i<nfds; i++) {
 		if (data[i] == 0x01)  {
 			FD_SET(i, dest_fd_set);
 		}
 	}
-	(*env).ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
+	env->ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
 	return;
 }
 
 void fdset2ztfdset(JNIEnv *env, int nfds, fd_set *src_fd_set, jobject dest_ztfd_set)
 {
-	jclass c = (*env).GetObjectClass(dest_ztfd_set);
+	jclass c = env->GetObjectClass(dest_ztfd_set);
 	if (!c) {
 		return;
 	}
 	jfieldID fid = env->GetFieldID(c, "fds_bits", "[B");
-	jobject fdData = (*env).GetObjectField (dest_ztfd_set, fid);
+	jobject fdData = env->GetObjectField (dest_ztfd_set, fid);
 	jbyteArray * arr = reinterpret_cast<jbyteArray*>(&fdData);
-	char *data = (char*)(*env).GetByteArrayElements(*arr, NULL);
+	char *data = (char*)env->GetByteArrayElements(*arr, NULL);
 	for (int i=0; i<nfds; i++) {
 		if (FD_ISSET(i, src_fd_set)) {
 			data[i] = 0x01;
 		}
 	}
-	(*env).ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
+	env->ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
 	return;
 }
 
@@ -721,78 +721,78 @@ void fdset2ztfdset(JNIEnv *env, int nfds, fd_set *src_fd_set, jobject dest_ztfd_
 
 void ss2zta(JNIEnv *env, struct sockaddr_storage *ss, jobject addr)
 {
-	jclass c = (*env).GetObjectClass(addr);
+	jclass c = env->GetObjectClass(addr);
 	if (!c) {
 		return;
 	}
 	if(ss->ss_family == AF_INET)
 	{
 		struct sockaddr_in *in4 = (struct sockaddr_in*)ss;
-		jfieldID fid = (*env).GetFieldID(c, "_port", "I");
+		jfieldID fid = env->GetFieldID(c, "_port", "I");
-		(*env).SetIntField(addr, fid, lwip_ntohs(in4->sin_port));
+		env->SetIntField(addr, fid, lwip_ntohs(in4->sin_port));
-		fid = (*env).GetFieldID(c,"_family", "I");
+		fid = env->GetFieldID(c,"_family", "I");
-		(*env).SetIntField(addr, fid, (in4->sin_family));
+		env->SetIntField(addr, fid, (in4->sin_family));
 		fid = env->GetFieldID(c, "_ip4", "[B");
-		jobject ipData = (*env).GetObjectField (addr, fid);
+		jobject ipData = env->GetObjectField (addr, fid);
 		jbyteArray * arr = reinterpret_cast<jbyteArray*>(&ipData);
-		char *data = (char*)(*env).GetByteArrayElements(*arr, NULL);
+		char *data = (char*)env->GetByteArrayElements(*arr, NULL);
 		memcpy(data, &(in4->sin_addr.s_addr), 4);
-		(*env).ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
+		env->ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
 
 		return;
 	}
 	if(ss->ss_family == AF_INET6)
 	{
 		struct sockaddr_in6 *in6 = (struct sockaddr_in6*)ss;
-		jfieldID fid = (*env).GetFieldID(c, "_port", "I");
+		jfieldID fid = env->GetFieldID(c, "_port", "I");
-		(*env).SetIntField(addr, fid, lwip_ntohs(in6->sin6_port));
+		env->SetIntField(addr, fid, lwip_ntohs(in6->sin6_port));
-		fid = (*env).GetFieldID(c,"_family", "I");
+		fid = env->GetFieldID(c,"_family", "I");
-		(*env).SetIntField(addr, fid, (in6->sin6_family));
+		env->SetIntField(addr, fid, (in6->sin6_family));
 		fid = env->GetFieldID(c, "_ip6", "[B");
-		jobject ipData = (*env).GetObjectField (addr, fid);
+		jobject ipData = env->GetObjectField (addr, fid);
 		jbyteArray * arr = reinterpret_cast<jbyteArray*>(&ipData);
-		char *data = (char*)(*env).GetByteArrayElements(*arr, NULL);
+		char *data = (char*)env->GetByteArrayElements(*arr, NULL);
 		memcpy(data, &(in6->sin6_addr.s6_addr), 16);
-		(*env).ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
+		env->ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
 		return;
 	}
 }
 
 void zta2ss(JNIEnv *env, struct sockaddr_storage *ss, jobject addr)
 {
-	jclass c = (*env).GetObjectClass(addr);
+	jclass c = env->GetObjectClass(addr);
 	if (!c) {
 		return;
 	}
-	jfieldID fid = (*env).GetFieldID(c, "_family", "I");
+	jfieldID fid = env->GetFieldID(c, "_family", "I");
-	int family = (*env).GetIntField(addr, fid);
+	int family = env->GetIntField(addr, fid);
 	if (family == AF_INET)
 	{
 		struct sockaddr_in *in4 = (struct sockaddr_in*)ss;
-		fid = (*env).GetFieldID(c, "_port", "I");
+		fid = env->GetFieldID(c, "_port", "I");
-		in4->sin_port = lwip_htons((*env).GetIntField(addr, fid));
+		in4->sin_port = lwip_htons(env->GetIntField(addr, fid));
 		in4->sin_family = AF_INET;
 		fid = env->GetFieldID(c, "_ip4", "[B");
-		jobject ipData = (*env).GetObjectField (addr, fid);
+		jobject ipData = env->GetObjectField (addr, fid);
 		jbyteArray * arr = reinterpret_cast<jbyteArray*>(&ipData);
-		char *data = (char*)(*env).GetByteArrayElements(*arr, NULL);
+		char *data = (char*)env->GetByteArrayElements(*arr, NULL);
 		memcpy(&(in4->sin_addr.s_addr), data, 4);
-		(*env).ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
+		env->ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
 		return;
 	}
 	if (family == AF_INET6)
 	{
 		struct sockaddr_in6 *in6 = (struct sockaddr_in6*)ss;
-		jfieldID fid = (*env).GetFieldID(c, "_port", "I");
+		jfieldID fid = env->GetFieldID(c, "_port", "I");
-		in6->sin6_port = lwip_htons((*env).GetIntField(addr, fid));
+		in6->sin6_port = lwip_htons(env->GetIntField(addr, fid));
-		fid = (*env).GetFieldID(c,"_family", "I");
+		fid = env->GetFieldID(c,"_family", "I");
 		in6->sin6_family = AF_INET6;
 		fid = env->GetFieldID(c, "_ip6", "[B");
-		jobject ipData = (*env).GetObjectField (addr, fid);
+		jobject ipData = env->GetObjectField (addr, fid);
 		jbyteArray * arr = reinterpret_cast<jbyteArray*>(&ipData);
-		char *data = (char*)(*env).GetByteArrayElements(*arr, NULL);
+		char *data = (char*)env->GetByteArrayElements(*arr, NULL);
 		memcpy(&(in6->sin6_addr.s6_addr), data, 16);
-		(*env).ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
+		env->ReleaseByteArrayElements(*arr, (jbyte*)data, 0);
 		return;
 	}
 }