+// ***************************************************************************
+// IBamIODevice.h (c) 2011 Derek Barnett
+// Marth Lab, Department of Biology, Boston College
+// ---------------------------------------------------------------------------
+// Last modified: 7 October 2011 (DB)
+// ---------------------------------------------------------------------------
+// Base class for all BAM I/O devices (e.g. local file, pipe, HTTP, FTP, etc.)
+//
+// Derived classes should provide protocol-specific implementations for
+// reading/writing plain bytes, as well as other I/O-related behaviors.
+//
+// Since IBamIODevices may be defined in client code, the internal
+// BamExceptions are NOT allowed to be thrown from devices, including the
+// built-in ones. This keeps a consistent interface at the BgzfStream for
+// handling any device type. Use the error string for relaying error messages.
+// ***************************************************************************
+
+#ifndef IBAMIODEVICE_H
+#define IBAMIODEVICE_H
+
+#include <api/api_global.h>
+#include <string>
+
+namespace BamTools {
+
+class API_EXPORT IBamIODevice {
+
+ // enums
+ public: enum OpenMode { NotOpen = 0
+ , ReadOnly
+ , WriteOnly
+ };
+
+ // ctor & dtor
+ public:
+ virtual ~IBamIODevice(void) { }
+
+ // IBamIODevice interface
+ public:
+
+ // pure virtuals
+ virtual void Close(void) =0;
+ virtual bool IsRandomAccess(void) const =0;
+ virtual bool Open(const OpenMode mode) =0;
+ virtual size_t Read(char* data, const unsigned int numBytes) =0;
+ virtual bool Seek(const int64_t& position) =0;
+ virtual int64_t Tell(void) const =0;
+ virtual size_t Write(const char* data, const unsigned int numBytes) =0;
+
+ // default implementation provided
+ virtual std::string GetErrorString(void);
+ virtual bool IsOpen(void) const;
+ virtual OpenMode Mode(void) const;
+
+ // internal methods
+ protected:
+ IBamIODevice(void); // hidden ctor
+ void SetErrorString(const std::string& where, const std::string& what);
+
+ // data members
+ protected:
+ OpenMode m_mode;
+ std::string m_errorString;
+};
+
+inline
+IBamIODevice::IBamIODevice(void)
+ : m_mode(IBamIODevice::NotOpen)
+{ }
+
+inline
+std::string IBamIODevice::GetErrorString(void) {
+ return m_errorString;
+}
+
+inline
+bool IBamIODevice::IsOpen(void) const {
+ return ( m_mode != IBamIODevice::NotOpen );
+}
+
+inline
+IBamIODevice::OpenMode IBamIODevice::Mode(void) const {
+ return m_mode;
+}
+
+inline
+void IBamIODevice::SetErrorString(const std::string& where, const std::string& what) {
+ static const std::string SEPARATOR = ": ";
+ m_errorString = where + SEPARATOR + what;
+}
+
+} // namespace BamTools
+
+#endif // IBAMIODEVICE_H