migrate 9pfs to use TextEncoder to fix 3 byte utf bug (#1139)

Makefile

@@ -84,7 +84,7 @@ CORE_FILES=const.js config.js io.js main.js lib.js buffer.js ide.js pci.js flopp
 	   state.js ne2k.js sb16.js virtio.js virtio_console.js bus.js log.js \
 	   cpu.js debug.js \
 	   elf.js kernel.js
-LIB_FILES=9p.js filesystem.js jor1k.js marshall.js utf8.js
+LIB_FILES=9p.js filesystem.js jor1k.js marshall.js
 BROWSER_FILES=screen.js keyboard.js mouse.js speaker.js serial.js \
 	      network.js starter.js worker_bus.js dummy_screen.js \
 	      fake_network.js wisp_network.js fetch_network.js print_stats.js filestorage.js

lib/filesystem.js

@@ -1338,7 +1338,7 @@ FS.prototype.FillDirectory = function(dirid) {
     let size = 0;
     for(const name of inode.direntries.keys())
     {
-        size += 13 + 8 + 1 + 2 + UTF8.UTF8Length(name);
+        size += 13 + 8 + 1 + 2 + texten.encode(name).length;
     }
     const data = this.inodedata[dirid] = new Uint8Array(size);
     inode.size = size;
@@ -1350,7 +1350,7 @@ FS.prototype.FillDirectory = function(dirid) {
         offset += marshall.Marshall(
             ["Q", "d", "b", "s"],
             [child.qid,
-            offset+13+8+1+2+UTF8.UTF8Length(name),
+            offset+13+8+1+2+texten.encode(name).length,
             child.mode >> 12,
             name],
             data, offset);

lib/marshall.js

@@ -7,6 +7,8 @@
 
 var marshall = {};
 
+const textde = new TextDecoder();
+const texten = new TextEncoder();
 
 // Inserts data from an array to a byte aligned struct in memory
 marshall.Marshall = function(typelist, input, struct, offset) {
@@ -48,14 +50,13 @@ marshall.Marshall = function(typelist, input, struct, offset) {
                 struct[offset++] = 0; // set the length later
                 struct[offset++] = 0;
                 size += 2;
-                for(var j of item) {
-                    var utf8 = UnicodeToUTF8Stream(j.charCodeAt(0));
-                    utf8.forEach( function(c) {
-                        struct[offset++] = c;
-                        size += 1;
-                        length++;
-                    });
-                }
+
+                var stringBytes = texten.encode(item);
+                size += stringBytes.byteLength;
+                length += stringBytes.byteLength;
+                struct.set(stringBytes, offset);
+                offset += stringBytes.byteLength;
+
                 struct[lengthoffset+0] = length & 0xFF;
                 struct[lengthoffset+1] = (length >> 8) & 0xFF;
                 break;
@@ -104,14 +105,10 @@ marshall.Unmarshall = function(typelist, struct, state) {
             case "s":
                 var len = struct[offset++];
                 len += struct[offset++] << 8;
-                var str = "";
-                var utf8converter = new UTF8StreamToUnicode();
-                for(var j=0; j < len; j++) {
-                    var c = utf8converter.Put(struct[offset++]);
-                    if(c === -1) continue;
-                    str += String.fromCharCode(c);
-                }
-                output.push(str);
+
+                var stringBytes = struct.slice(offset, offset + len);
+                offset += len;
+                output.push(textde.decode(stringBytes));
                 break;
             case "Q":
                 state.offset = offset;