cid tweaks, tests

Author: robamu

src/sdcard/cid.rs

@@ -17,16 +17,16 @@ pub struct Cid {
     manufacturer_id: u8,
     /// OID.
     #[bits(104..=119, rw)]
-    application_id: u16,
+    oem_id: u16,
     /// PVM.
     #[bits(64..=103, rw)]
-    product_name: u40,
+    product_name_raw: u40,
     /// PSN.
     #[bits(24..=55, rw)]
     product_serial_number: u32,
     /// MDT.
     #[bits(8..=19, rw)]
-    manufacturing_data: u12,
+    manufacturing_date: u12,
     /// CRC.
     #[bits(1..=7, rw)]
     crc7: u7,
@@ -53,4 +53,56 @@ impl Cid {
         let calculated = crc7(&raw_bytes[0..15]);
         self.crc7().value() == calculated
     }
+
+    /// Product name as a byte array.
+    #[inline]
+    pub fn product_name_bytes(&self) -> [u8; 5] {
+        self.product_name_raw().to_be_bytes()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn basic_test() {
+        // CID retrieved from a real SD card.
+        let raw_cid = [
+            0x12, 0x34, 0x56, 0x41, 0x53, 0x54, 0x43, 0x0, 0x20, 0x0, 0x0, 0xc, 0xef, 0x1, 0x65,
+            0xef,
+        ];
+        // This also verifies the checksum.
+        let cid = Cid::new(&raw_cid);
+        assert!(cid.is_ok());
+
+        let cid = cid.unwrap();
+        // https://www.bahjeez.com/sd-card-manufacturer-ids/: Patriot.
+        assert_eq!(cid.manufacturer_id(), 0x12);
+        assert_eq!(cid.oem_id(), 0x3456);
+
+        let product_name_raw = cid.product_name_bytes();
+        let product_name = core::str::from_utf8(&product_name_raw).unwrap();
+        assert_eq!(product_name, "ASTC\0");
+    }
+
+    #[test]
+    fn basic_test_unchecked() {
+        // CID retrieved from a real SD card.
+        let raw_cid = [
+            0x12, 0x34, 0x56, 0x41, 0x53, 0x54, 0x43, 0x0, 0x20, 0x0, 0x0, 0xc, 0xef, 0x1, 0x65,
+            0x00,
+        ];
+        // Invalid checksum ignored.
+        let cid = Cid::new_unchecked(&raw_cid);
+        assert!(!cid.verify_crc7());
+
+        // https://www.bahjeez.com/sd-card-manufacturer-ids/: Patriot.
+        assert_eq!(cid.manufacturer_id(), 0x12);
+        assert_eq!(cid.oem_id(), 0x3456);
+
+        let product_name_raw = cid.product_name_bytes();
+        let product_name = core::str::from_utf8(&product_name_raw).unwrap();
+        assert_eq!(product_name, "ASTC\0");
+    }
 }