feat: add dump functionality

libsession-util/src/androidTest/java/network/loki/messenger/libsession_util/InstrumentedTests.kt

@@ -89,7 +89,21 @@ class InstrumentedTests {
 
         assertEquals(1, newSeqNo)
         assertArrayEquals(expectedPush1, newToPush)
+        // We haven't dumped, so still need to dump:
+        assertTrue(userProfile.needsDump())
+        // We did call push but we haven't confirmed it as stored yet, so this will still return true:
+        assertTrue(userProfile.needsPush())
 
+        val dump = userProfile.dump()
+        // (in a real client we'd now store this to disk)
+        assertFalse(userProfile.needsDump())
+        val expectedDump = ("d" +
+                "1:!i2e" +
+                "1:$").encodeToByteArray() + expectedPush1.size.toString().encodeToByteArray() +
+                ":".encodeToByteArray() + expectedPush1 +
+                "e".encodeToByteArray()
+
+        assertArrayEquals(expectedDump, dump)
 
         userProfile.free()
     }

libsession-util/src/main/cpp/session_util.cpp

@@ -137,4 +137,12 @@ Java_network_loki_messenger_libsession_1util_UserProfile_setPic(JNIEnv *env, job
     auto* pic_string = new std::string(pic_chars);
 
     profile->set_profile_pic(*pic_string, key_str);
+}
+extern "C"
+JNIEXPORT jbyteArray JNICALL
+Java_network_loki_messenger_libsession_1util_ConfigBase_dump(JNIEnv *env, jobject thiz) {
+    auto config = ptrToConfigBase(env, thiz);
+    std::string dumped = config->dump();
+    jbyteArray bytes = bytes_from_string(env, dumped);
+    return bytes;
 }

libsession-util/src/main/java/network/loki/messenger/libsession_util/Config.kt

@@ -13,6 +13,7 @@ sealed class ConfigBase(protected val /* yucky */ pointer: Long) {
     external fun needsPush(): Boolean
     external fun needsDump(): Boolean
     external fun push(): ConfigWithSeqNo
+    external fun dump(): ByteArray
 }
 
 class UserProfile(pointer: Long): ConfigBase(pointer) {