Merged in read_capacity (pull request #5)

Impl Read Capacity SCSI command. fixes issue #9.
alphadev-net · Sep 7, 2014 · 821df0b · 821df0b
2 parents fe8ba9c + d81708b
commit 821df0b
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Showing 3 changed files with 115 additions and 16 deletions.
diff --git a/lib/src/main/java/net/alphadev/usbstorage/bbb/BulkBlockDevice.java b/lib/src/main/java/net/alphadev/usbstorage/bbb/BulkBlockDevice.java
@@ -1,10 +1,12 @@
 package net.alphadev.usbstorage.bbb;
 
 import net.alphadev.usbstorage.api.BulkDevice;
+import net.alphadev.usbstorage.scsi.answer.ReadCapacityResponse;
 import net.alphadev.usbstorage.scsi.answer.ReadFormatCapacitiesEntry;
 import net.alphadev.usbstorage.scsi.answer.ReadFormatCapacitiesHeader;
 import net.alphadev.usbstorage.scsi.answer.StandardInquiryAnswer;
 import net.alphadev.usbstorage.scsi.command.Inquiry;
+import net.alphadev.usbstorage.scsi.command.ReadCapacity;
 import net.alphadev.usbstorage.scsi.command.ReadFormatCapacities;
 import net.alphadev.usbstorage.scsi.command.ScsiCommand;
 import net.alphadev.usbstorage.scsi.command.TestUnitReady;
@@ -30,39 +32,58 @@ public BulkBlockDevice(BulkDevice usbBlockDevice) throws IOException {
 
         setupInquiryPhase();
         setupCapacityPhase();
-        testReady();
+        testUnitReady();
     }
 
-    private void testReady() throws IOException {
+    private void testUnitReady() throws IOException {
         send_mass_storage_command(new TestUnitReady());
 
-        CommandStatusWrapper csw = retrieve_mass_storage_answer();
-        if (CommandStatusWrapper.Status.COMMAND_PASSED != csw.getStatus()) {
-            throw new IllegalStateException("device signaled error state!");
-        }
+        checkDeviceStatus();
     }
 
     private void setupCapacityPhase() throws IOException {
         try {
             send_mass_storage_command(new ReadFormatCapacities());
             byte[] answer = mAbstractBulkDevice.retrieve_data_packet(ReadFormatCapacitiesHeader.LENGTH);
             ReadFormatCapacitiesHeader capacity = new ReadFormatCapacitiesHeader(answer);
-            CommandStatusWrapper csw = retrieve_mass_storage_answer();
-            if (CommandStatusWrapper.Status.COMMAND_PASSED != csw.getStatus()) {
-                throw new IllegalStateException("device signaled error state!");
-            }
+            checkDeviceStatus();
 
             for (int i = 0; i < capacity.getCapacityEntryCount(); i++) {
                 byte[] capacityData = mAbstractBulkDevice.retrieve_data_packet(ReadFormatCapacitiesEntry.LENGTH);
                 new ReadFormatCapacitiesEntry(capacityData);
             }
 
             // determine the last addressable block
-            mDeviceBoundaries = capacity.getNumberOfBlocks();
-            mBlockSize = capacity.getBlockLength();
+            if (capacity.getNumberOfBlocks() != 0) {
+                mDeviceBoundaries = capacity.getNumberOfBlocks();
+            }
+
+            if (capacity.getBlockLength() != 0) {
+                mBlockSize = capacity.getBlockLength();
+            }
         } catch (IllegalArgumentException ex) {
             // do nothing as the read format capacities command is optional.
         }
+
+        try {
+            send_mass_storage_command(new ReadCapacity());
+            byte[] answer = mAbstractBulkDevice.retrieve_data_packet(ReadCapacityResponse.LENGTH);
+            ReadCapacityResponse capacity = new ReadCapacityResponse(answer);
+
+            checkDeviceStatus();
+
+            mDeviceBoundaries = capacity.getNumberOfBlocks();
+            mBlockSize = capacity.getBlockSize();
+        } catch (IllegalArgumentException e) {
+            // whaaat!
+        }
+    }
+
+    private void checkDeviceStatus() {
+        CommandStatusWrapper csw = retrieve_mass_storage_answer();
+        if (CommandStatusWrapper.Status.COMMAND_PASSED != csw.getStatus()) {
+            throw new IllegalStateException("device signaled error state!");
+        }
     }
 
     private void setupInquiryPhase() throws IOException {
@@ -71,10 +92,7 @@ private void setupInquiryPhase() throws IOException {
         byte[] answer = mAbstractBulkDevice.retrieve_data_packet(StandardInquiryAnswer.LENGTH);
         new StandardInquiryAnswer(answer);
 
-        CommandStatusWrapper csw = retrieve_mass_storage_answer();
-        if (CommandStatusWrapper.Status.COMMAND_PASSED != csw.getStatus()) {
-            throw new IllegalStateException("device signaled error state!");
-        }
+        checkDeviceStatus();
     }
 
     private CommandStatusWrapper retrieve_mass_storage_answer() {

diff --git a/lib/src/main/java/net/alphadev/usbstorage/scsi/answer/ReadCapacityResponse.java b/lib/src/main/java/net/alphadev/usbstorage/scsi/answer/ReadCapacityResponse.java
@@ -0,0 +1,26 @@
+package net.alphadev.usbstorage.scsi.answer;
+
+import static net.alphadev.usbstorage.util.BitStitching.convertToInt;
+
+/**
+ * @author Jan Seeger <[email protected]>
+ */
+public class ReadCapacityResponse {
+    public static final int LENGTH = 8;
+
+    private int mBlockSize;
+    private int mNumberOfBlocks;
+
+    public ReadCapacityResponse(byte[] answer) {
+        mNumberOfBlocks = convertToInt(answer, 0);
+        mBlockSize = convertToInt(answer, 4);
+    }
+
+    public int getBlockSize() {
+        return mBlockSize;
+    }
+
+    public int getNumberOfBlocks() {
+        return mNumberOfBlocks;
+    }
+}
diff --git a/lib/src/main/java/net/alphadev/usbstorage/scsi/command/ReadCapacity.java b/lib/src/main/java/net/alphadev/usbstorage/scsi/command/ReadCapacity.java
@@ -0,0 +1,55 @@
+package net.alphadev.usbstorage.scsi.command;
+
+import net.alphadev.usbstorage.bbb.CommandBlockWrapper;
+import net.alphadev.usbstorage.scsi.answer.ReadCapacityResponse;
+
+import static net.alphadev.usbstorage.util.BitStitching.setBytesFromInt;
+
+/**
+ * @author Jan Seeger <[email protected]>
+ */
+@SuppressWarnings("unused")
+public class ReadCapacity extends ScsiCommand {
+    public static final byte READ_CAPACITY = 0x25;
+
+    private int mLogicalBlockAddress;
+    private byte mControl;
+
+    public ReadCapacity() {
+        super(READ_CAPACITY);
+    }
+
+    @Override
+    public CommandBlockWrapper.Direction getDirection() {
+        return CommandBlockWrapper.Direction.DEVICE_TO_HOST;
+    }
+
+    @Override
+    public byte[] asBytes() {
+        byte[] retval = new byte[10];
+        retval[0] = READ_CAPACITY; // opcode
+        // retval[1] is reserved
+        setBytesFromInt(mLogicalBlockAddress, retval, 2);
+        // retval[6-8] is reserved
+        retval[9] = mControl;
+        return retval;
+    }
+
+
+    @Override
+    public int getExpectedAnswerLength() {
+        return ReadCapacityResponse.LENGTH;
+    }
+
+    public int getLogicalBlockAddress() {
+        return mLogicalBlockAddress;
+    }
+
+    public void setLogicalBlockAddress(int logicalBlockAddress) {
+        this.mLogicalBlockAddress = logicalBlockAddress;
+    }
+
+    public void setControl(byte control) {
+        this.mControl = control;
+    }
+}