Device: Add disk read driver framework

Allow access to the device's logical disk.

At the moment, no drivers are implemented, so all devices have Access::None.

include/icsneo/api/event.h

@@ -47,6 +47,7 @@ public:
 		UnsupportedTXNetwork = 0x1011,
 		MessageMaxLengthExceeded = 0x1012,
 		ValueNotYetPresent = 0x1013,
+		Timeout = 0x1014,
 		
 		// Device Events
 		PollingMessageOverflow = 0x2000,
@@ -80,6 +81,8 @@ public:
 		NoSerialNumber12V = 0x2028, // The device must be powered with 12V for communication to be established
 		NoSerialNumberFW12V = 0x2029, // The device must be powered with 12V for communication to be established, a firmware update was already attempted
 		EthPhyRegisterControlNotAvailable = 0x2030, //The device doesn't support Ethernet PHY MDIO access
+		DiskNotSupported = 0x2031,
+		EOFReached = 0x2032,
 		SettingsDefaultsUsed = 0x2033,
 
 		// Transport Events

include/icsneo/device/device.h

@@ -16,6 +16,8 @@
 #include "icsneo/device/nullsettings.h"
 #include "icsneo/device/devicetype.h"
 #include "icsneo/device/deviceversion.h"
+#include "icsneo/disk/diskreaddriver.h"
+#include "icsneo/disk/nulldiskreaddriver.h"
 #include "icsneo/communication/communication.h"
 #include "icsneo/communication/packetizer.h"
 #include "icsneo/communication/encoder.h"
@@ -139,6 +141,23 @@ public:
 	virtual size_t getNetworkCountByType(Network::Type) const;
 	virtual Network getNetworkByNumber(Network::Type, size_t) const;
 
+	/**
+	 * Read from the logical disk in this device, starting from byte `pos`
+	 * and reading up to `amount` bytes.
+	 * 
+	 * The number of bytes read will be returned in case of success.
+	 * 
+	 * If the number of bytes read is less than the amount requested,
+	 * an error will be set in icsneo::GetLastError() explaining why.
+	 * Likely, either the end of the logical disk has been reached, or
+	 * the timeout was reached while the read had only partially completed.
+	 *
+	 * Upon failure, icsneo::nullopt will be returned and an error will be
+	 * set in icsneo::GetLastError().
+	 */
+	optional<uint64_t> readLogicalDisk(uint64_t pos, uint8_t* into, uint64_t amount,
+		std::chrono::milliseconds timeout = DiskReadDriver::DefaultTimeout);
+
 	/**
 	 * Retrieve the number of Ethernet (DoIP) Activation lines present
 	 * on this device.
@@ -257,7 +276,7 @@ protected:
 		data.device = this;
 	}
 	
-	template<typename Driver, typename Settings = NullSettings>
+	template<typename Driver, typename Settings = NullSettings, typename DiskRead = NullDiskReadDriver>
 	void initialize() {
 		report = makeEventHandler();
 		auto driver = makeDriver<Driver>();
@@ -270,6 +289,7 @@ protected:
 		setupCommunication(*com);
 		settings = makeSettings<Settings>(com);
 		setupSettings(*settings);
+		diskReadDriver = std::make_unique<DiskRead>();
 		setupSupportedRXNetworks(supportedRXNetworks);
 		setupSupportedTXNetworks(supportedTXNetworks);
 		setupExtensions();
@@ -345,6 +365,7 @@ private:
 	neodevice_t data;
 	std::shared_ptr<ResetStatusMessage> latestResetStatus;
 	std::vector<optional<DeviceAppVersion>> versions;
+	std::unique_ptr<DiskReadDriver> diskReadDriver;
 
 	mutable std::mutex extensionsLock;
 	std::vector<std::shared_ptr<DeviceExtension>> extensions;

include/icsneo/disk/diskreaddriver.h

@@ -0,0 +1,47 @@
+#ifndef __DISKREADDRIVER_H__
+#define __DISKREADDRIVER_H__
+
+#ifdef __cplusplus
+
+#include "icsneo/platform/optional.h"
+#include "icsneo/communication/communication.h"
+#include "icsneo/api/eventmanager.h"
+#include <cstdint>
+#include <chrono>
+
+namespace icsneo {
+
+/**
+ * Interface for drivers which read block data from devices
+ */
+class DiskReadDriver {
+public:
+	static constexpr const std::chrono::milliseconds DefaultTimeout{2000};
+	static constexpr const size_t SectorSize = 512;
+	enum class Access {
+		None,
+		EntireCard,
+		VSA
+	};
+
+	virtual ~DiskReadDriver() = default;
+	virtual optional<uint64_t> readLogicalDisk(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout = DefaultTimeout);
+	virtual Access getAccess() const = 0;
+	virtual std::pair<uint32_t, uint32_t> getBlockSizeBounds() const = 0;
+
+protected:
+	/**
+	 * Perform a read which the driver can do in one shot.
+	 * 
+	 * The `pos` requested must be sector-aligned, and the `amount` must be
+	 * within the block size bounds provided by the driver.
+	 */
+	virtual optional<uint64_t> readLogicalDiskAligned(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout) = 0;
+};
+
+}
+
+#endif // __cplusplus
+#endif // __DISKREADDRIVER_H__

include/icsneo/disk/nulldiskreaddriver.h

@@ -0,0 +1,30 @@
+#ifndef __NULLDISKREADDRIVER_H__
+#define __NULLDISKREADDRIVER_H__
+
+#ifdef __cplusplus
+
+#include "icsneo/disk/diskreaddriver.h"
+
+namespace icsneo {
+
+/**
+ * A disk driver which always returns the requested disk as unsupported
+ * 
+ * Used for devices which do not have a disk, or do not provide any means for accessing it
+ */
+class NullDiskReadDriver : public DiskReadDriver {
+public:
+	optional<uint64_t> readLogicalDisk(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout = DefaultTimeout) override;
+	Access getAccess() const override { return Access::None; }
+	std::pair<uint32_t, uint32_t> getBlockSizeBounds() const override { return {SectorSize, SectorSize}; }
+
+private:
+	optional<uint64_t> readLogicalDiskAligned(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout) override;
+};
+
+}
+
+#endif // __cplusplus
+#endif // __NULLDISKREADDRIVER_H__