[Filesystem] Fix SMP support in UTF-8 encoding on write

Support supplementary planes, including Emoji.

[Verification] readASText() is working correctly for P170111-07658 issue.

Change-Id: I6f75f397e167ea9c89b4298edcaa19352586c90d
Signed-off-by: Jakub Skowron <j.skowron@samsung.com>

diff --git a/src/filesystem/js/base64.js b/src/filesystem/js/base64.js
index 034ce33..d2868f3 100755 (executable)
--- a/src/filesystem/js/base64.js
+++ b/src/filesystem/js/base64.js
@@ -16,13 +16,8 @@
 
 var Base64 = {
   _b64: 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=',
-  encodeString: function(data) {
-    data = this._utf8_encode(data);
-    var input = [];
-    for (var i = 0; i < data.length; ++i) {
-      input.push(data.charCodeAt(i));
-    }
-    return this.encode(input);
+  encodeString: function(str) {
+    return this.encode(this._utf8_encode(str));
   },
   encode: function(data) {
     var output = '';
@@ -90,28 +85,29 @@ var Base64 = {
   },
   _utf8_encode: function(str) {
     str = str.replace(/\r\n/g, '\n');
-    var utftext = '';
-
-    for (var n = 0; n < str.length; n++) {
+    var utfarray = [];
 
-      var c = str.charCodeAt(n);
+    //TODO: use for( var c of str ) in future versions
+    for (var offset = 0; offset < str.length; offset++) {
+      var code = str.codePointAt(offset);
 
-      if (c < 128) {
-        utftext += String.fromCharCode(c);
+      if (code <= 0x7F) {
+        utfarray.push(code);
       }
-      else if ((c > 127) && (c < 2048)) {
-        utftext += String.fromCharCode((c >> 6) | 192);
-        utftext += String.fromCharCode((c & 63) | 128);
+      else if (code <= 0x7FF) {
+        utfarray.push( 0xC0 | (code >> 6), 0x80 | (code & 0x3F) );
+      }
+      else if (code <= 0xFFFF) {
+        utfarray.push( 0xE0 | (code >> 12), 0x80 | ((code >> 6) & 0x3F), 0x80 | (code & 0x3F) );
       }
       else {
-        utftext += String.fromCharCode((c >> 12) | 224);
-        utftext += String.fromCharCode(((c >> 6) & 63) | 128);
-        utftext += String.fromCharCode((c & 63) | 128);
+        utfarray.push( 0xF0 | (code >> 18), 0x80 | ((code >> 12) & 0x3F),
+                       0x80 | ((code >> 6) & 0x3F), 0x80 | (code & 0x3F) );
+        offset++; //there is a UTF16 surrogate pair in str, so jump two elements
       }
-
     }
 
-    return utftext;
+    return utfarray;
   },
   _utf8_decode: function(utfarray) {
     var str = '';
@@ -125,12 +121,12 @@ var Base64 = {
         str += String.fromCharCode(c);
         i++;
       }
-      else if ((c > 191) && (c < 224)) {
+      else if ((c >= 192) && (c < 224)) {
         c1 = utfarray[i + 1];
         str += String.fromCharCode(((c & 31) << 6) | (c1 & 63));
         i += 2;
       }
-      else if((c > 223) && (c < 240)) {
+      else if((c >= 224) && (c < 240)) {
         c1 = utfarray[i + 1];
         c2 = utfarray[i + 2];
         str += String.fromCharCode(((c & 15) << 12) | ((c1 & 63) << 6) | (c2 & 63));