Improved logging

app/src/main/java/eu/faircode/email/Log.java

@@ -532,7 +532,7 @@ public class Log {
                             if (element instanceof Long)
                                 elements[i] = element.toString() + " (0x" + Long.toHexString((Long) element) + ")";
                             else
-                                elements[i] = (element == null ? null : element.toString());
+                                elements[i] = (element == null ? null : printableString(element.toString()));
                         }
                         value = TextUtils.join(",", elements);
                     } else
@@ -550,6 +550,22 @@ public class Log {
         return result;
     }
 
+    private static String printableString(String value) {
+        StringBuilder result = new StringBuilder();
+        for (int i = 0; i < value.length(); i++) {
+            char kar = value.charAt(i);
+            if (kar == '\n')
+                result.append('|');
+            else if (kar == ' ')
+                result.append('_');
+            else if (!Helper.isPrintableChar(kar))
+                result.append('{').append(Integer.toHexString(kar)).append('}');
+            else
+                result.append(kar);
+        }
+        return result.toString();
+    }
+
     static void logMemory(Context context, String message) {
         ActivityManager.MemoryInfo mi = new ActivityManager.MemoryInfo();
         ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);