Fix the decrypt issue (crash on V5.1.1) when the message to decrypt contains emojis:AndroidSdk_v0.2.0

- add an internal specific JNI function (javaCStringToUtf8()) to perform the UTF-8 conversion
- the SDK is configured to enable/disable the use of javaCStringToUtf8()

3 files changed, 26 insertions, 4 deletions

diff --git a/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java b/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java
index 50e77f7..fa4ca1d 100644
--- a/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java
+++ b/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java
@@ -123,16 +123,26 @@ public class OlmInboundGroupSession extends CommonSerializeUtils implements Seri
     private native int initInboundGroupSessionWithSessionKeyJni(String aSessionKey);
 
 
+    /**
+     * Retrieve the base64-encoded identifier for this inbound group session.
+     * @return the session ID if operation succeed, null otherwise
+     */
     public String sessionIdentifier() {
         return sessionIdentifierJni();
     }
     private native String sessionIdentifierJni();
 
 
+    /**
+     * Decrypt the message passed in parameter.
+     * @param aEncryptedMsg the message to be decrypted
+     * @return the decrypted message if operation succeed, null otherwise.
+     */
     public String decryptMessage(String aEncryptedMsg) {
-        return decryptMessageJni(aEncryptedMsg);
+        String decryptedMessage = decryptMessageJni(aEncryptedMsg, OlmManager.ENABLE_STRING_UTF8_SPECIFIC_CONVERSION);
+        return decryptedMessage;
     }
-    private native String decryptMessageJni(String aEncryptedMsg);
+    private native String decryptMessageJni(String aEncryptedMsg, boolean aIsUtf8ConversionRequired);
 
 
     /**
diff --git a/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmManager.java b/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmManager.java
index 92fbe2b..5170ee9 100644
--- a/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmManager.java
+++ b/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmManager.java
@@ -25,6 +25,18 @@ import android.util.Log;
 public class OlmManager {
     private static final String LOG_TAG = "OlmManager";
     private static final String SDK_OLM_VERSION = "V0.1.0_1";
+    /** specific flag to enable UTF-8 specific conversion for pre Marshmallow(23) android versions.<br>
+     * <a href="https://github.com/eclipsesource/J2V8/issues/142">NDK NewStringUTF() UTF8 issue</a>
+     **/
+    public static boolean ENABLE_STRING_UTF8_SPECIFIC_CONVERSION;
+
+    /**
+     * Constructor.
+     * @param aIsUtf8SpecificConversionEnabled true to enable JNI specific UTF-8 conversion, false otherwie
+     */
+    public OlmManager(boolean aIsUtf8SpecificConversionEnabled) {
+        ENABLE_STRING_UTF8_SPECIFIC_CONVERSION = aIsUtf8SpecificConversionEnabled;
+    }
 
     static {
         try {
diff --git a/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmSession.java b/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmSession.java
index 6d570d1..dddc588 100644
--- a/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmSession.java
+++ b/java/android/OlmLibSdk/olm-sdk/src/main/java/org/matrix/olm/OlmSession.java
@@ -361,10 +361,10 @@ public class OlmSession extends CommonSerializeUtils implements Serializable {
      * @return the decrypted message if operation succeed, null otherwise
      */
     public String decryptMessage(OlmMessage aEncryptedMsg) {
-        return decryptMessageJni(aEncryptedMsg);
+        return decryptMessageJni(aEncryptedMsg, OlmManager.ENABLE_STRING_UTF8_SPECIFIC_CONVERSION);
     }
 
-    private native String decryptMessageJni(OlmMessage aEncryptedMsg);
+    private native String decryptMessageJni(OlmMessage aEncryptedMsg, boolean aIsUtf8ConversionRequired);
 
     /**
      * Return the number of unreleased OlmSession instances.<br>