Fixed bug with % encoding

The app crashes when %25 exists in the body of mailto (actually also
crashes if it's in the subject). This is caused by attempting to
decode % encoding twice through getQueryParameters and URLDecoder.decode.

e.g. body=Bye%25Bye, after getQueryParameters. the string turns into
Bye%Bye, then passing that into URLDecoder.decode will throw error
because %Bye is not a valid % encoding.

To fix, we manually re-encode %, then run it through URLDecoder to
get the correct message.

Added unit tests to test full functionality of initFromMailTo with
various inputs to make sure that they are displayed correctly. Tested
original bug on phone, and % sign is rendered correctly with no crashes.

b/12441256

Change-Id: I06b2a4378f11de58d59b4978db1af751928570c7

1 files changed, 28 insertions, 13 deletions

diff --git a/src/com/android/mail/compose/ComposeActivity.java b/src/com/android/mail/compose/ComposeActivity.java
index c0768edb3..3a285a556 100644
--- a/src/com/android/mail/compose/ComposeActivity.java
+++ b/src/com/android/mail/compose/ComposeActivity.java
@@ -1465,6 +1465,31 @@ public class ComposeActivity extends Activity implements OnClickListener, OnNavi
     }
 
     /**
+     * Replaces all occurrences of '%' with "%25", to prevent URLDecode.decode from
+     * crashing on decoded '%' symbols
+     *
+     * @param toReplace Input string
+     * @return The string with all "%" characters replaced with "%25"
+     */
+    private static String replacePercent(String toReplace) {
+        return toReplace.replace("%", "%25");
+    }
+
+    /**
+     * Helper function to encapsulate encoding/decoding string from Uri.getQueryParameters
+     * @param content Input string
+     * @return The string that's properly escaped to be shown in mail subject/content
+     */
+    private static String decodeContentFromQueryParam(String content) {
+        try {
+            return URLDecoder.decode(replacePlus(replacePercent(content)), UTF8_ENCODING_NAME);
+        } catch (UnsupportedEncodingException e) {
+            LogUtils.e(LOG_TAG, "%s while decoding '%s'", e.getMessage(), content);
+            return "";  // Default to empty string so setText/setBody has same behavior as before.
+        }
+    }
+
+    /**
      * Initialize the compose view from a String representing a mailTo uri.
      * @param mailToString The uri as a string.
      */
@@ -1502,25 +1527,15 @@ public class ComposeActivity extends Activity implements OnClickListener, OnNavi
         List<String> bcc = uri.getQueryParameters("bcc");
         addBccAddresses(Arrays.asList(bcc.toArray(new String[bcc.size()])));
 
+        // NOTE: Uri.getQueryParameters already decodes % encoded characters
         List<String> subject = uri.getQueryParameters("subject");
         if (subject.size() > 0) {
-            try {
-                mSubject.setText(URLDecoder.decode(replacePlus(subject.get(0)),
-                        UTF8_ENCODING_NAME));
-            } catch (UnsupportedEncodingException e) {
-                LogUtils.e(LOG_TAG, "%s while decoding subject '%s'",
-                        e.getMessage(), subject);
-            }
+            mSubject.setText(decodeContentFromQueryParam(subject.get(0)));
         }
 
         List<String> body = uri.getQueryParameters("body");
         if (body.size() > 0) {
-            try {
-                setBody(URLDecoder.decode(replacePlus(body.get(0)), UTF8_ENCODING_NAME),
-                        true /* with signature */);
-            } catch (UnsupportedEncodingException e) {
-                LogUtils.e(LOG_TAG, "%s while decoding body '%s'", e.getMessage(), body);
-            }
+            setBody(decodeContentFromQueryParam(body.get(0)), true /* with signature */);
         }
     }