fix mtp serial

examples/device/mtp/src/mtp_fs_example.c

@@ -351,9 +351,10 @@ static int32_t fs_get_device_info(tud_mtp_cb_data_t* cb_data) {
   mtp_container_add_cstring(io_container, DEV_INFO_MODEL);
   mtp_container_add_cstring(io_container, DEV_INFO_VERSION);
 
-  uint16_t serial_utf16[32];
-  size_t nchars = board_usb_get_serial(serial_utf16, 32);
-  serial_utf16[tu_min32(nchars, 31u)] = 0; // ensure null termination
+  enum { MAX_SERIAL_NCHARS = 32 };
+  uint16_t serial_utf16[MAX_SERIAL_NCHARS+1];
+  size_t nchars = board_usb_get_serial(serial_utf16, MAX_SERIAL_NCHARS);
+  serial_utf16[tu_min32(nchars, MAX_SERIAL_NCHARS)] = 0; // ensure null termination
   mtp_container_add_string(io_container, serial_utf16);
 
   tud_mtp_data_send(io_container);

test/hil/hil_test.py

@@ -142,6 +142,7 @@ def open_mtp_dev(uid):
     mtp = MTP()
     timeout = ENUM_TIMEOUT
     while timeout > 0:
+        # run_cmd(f"gio mount -u mtp://TinyUsb_TinyUsb_Device_{uid}/")
         for raw in mtp.detect_devices():
             mtp.device = mtp.mtp.LIBMTP_Open_Raw_Device(ctypes.byref(raw))
             if mtp.device and mtp.get_serialnumber().decode('utf-8') == uid:
@@ -526,42 +527,44 @@ def test_device_mtp(board):
     if mtp is None or mtp.device is None:
         assert False, 'MTP device not found'
 
-    assert b"TinyUSB" == mtp.get_manufacturer(), 'MTP wrong manufacturer'
-    assert b"MTP Example" == mtp.get_modelname(), 'MTP wrong model'
-    assert b'1.0' == mtp.get_deviceversion(), 'MTP wrong version'
-    assert b'TinyUSB MTP' == mtp.get_devicename(), 'MTP wrong device name'
-
-    # read and compare readme.txt and logo.png
-    f1_expect = b'TinyUSB MTP Filesystem example'
-    f2_md5_expect = '40ef23fc2891018d41a05d4a0d5f822f' # md5sum of logo.png
-    f1 = uid.encode("utf-8") + b'_file1'
-    f2 = uid.encode("utf-8") + b'_file2'
-    f3 = uid.encode("utf-8") + b'_file3'
-    mtp.get_file_to_file(1, f1)
-    with open(f1, 'rb') as file:
-        f1_data = file.read()
-        os.remove(f1)
-        assert f1_data == f1_expect, 'MTP file1 wrong data'
-    mtp.get_file_to_file(2, f2)
-    with open(f2, 'rb') as file:
-        f2_data = file.read()
-        os.remove(f2)
-        assert f2_md5_expect == hashlib.md5(f2_data).hexdigest(), 'MTP file2 wrong data'
-    # test send file
-    with open(f3, "wb") as file:
-        f3_data = os.urandom(random.randint(1024, 3*1024))
-        file.write(f3_data)
-        file.close()
-        fid = mtp.send_file_from_file(f3, b'file3')
-        f3_readback = f3 + b'_readback'
-        mtp.get_file_to_file(fid, f3_readback)
-        with open(f3_readback, 'rb') as f:
-            f3_rb_data = f.read()
-            os.remove(f3_readback)
-            assert f3_rb_data == f3_data, 'MTP file3 wrong data'
-        os.remove(f3)
-        mtp.delete_object(fid)
+    try:
+        assert b"TinyUSB" == mtp.get_manufacturer(), 'MTP wrong manufacturer'
+        assert b"MTP Example" == mtp.get_modelname(), 'MTP wrong model'
+        assert b'1.0' == mtp.get_deviceversion(), 'MTP wrong version'
+        assert b'TinyUSB MTP' == mtp.get_devicename(), 'MTP wrong device name'
 
+        # read and compare readme.txt and logo.png
+        f1_expect = b'TinyUSB MTP Filesystem example'
+        f2_md5_expect = '40ef23fc2891018d41a05d4a0d5f822f' # md5sum of logo.png
+        f1 = uid.encode("utf-8") + b'_file1'
+        f2 = uid.encode("utf-8") + b'_file2'
+        f3 = uid.encode("utf-8") + b'_file3'
+        mtp.get_file_to_file(1, f1)
+        with open(f1, 'rb') as file:
+            f1_data = file.read()
+            os.remove(f1)
+            assert f1_data == f1_expect, 'MTP file1 wrong data'
+        mtp.get_file_to_file(2, f2)
+        with open(f2, 'rb') as file:
+            f2_data = file.read()
+            os.remove(f2)
+            assert f2_md5_expect == hashlib.md5(f2_data).hexdigest(), 'MTP file2 wrong data'
+        # test send file
+        with open(f3, "wb") as file:
+            f3_data = os.urandom(random.randint(1024, 3*1024))
+            file.write(f3_data)
+            file.close()
+            fid = mtp.send_file_from_file(f3, b'file3')
+            f3_readback = f3 + b'_readback'
+            mtp.get_file_to_file(fid, f3_readback)
+            with open(f3_readback, 'rb') as f:
+                f3_rb_data = f.read()
+                os.remove(f3_readback)
+                assert f3_rb_data == f3_data, 'MTP file3 wrong data'
+            os.remove(f3)
+            mtp.delete_object(fid)
+    finally:
+        mtp.disconnect()
 
 
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