soma-io  4.5.0
datasource.h
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33 
34 #ifndef SOMAIO_DATASOURCE_DATASOURCE_H
35 #define SOMAIO_DATASOURCE_DATASOURCE_H
36 //--- soma-io ----------------------------------------------------------------
38 //--- cartobase --------------------------------------------------------------
39 #include <cartobase/smart/rcptr.h> // declares base class RCObject
40 //--- system -----------------------------------------------------------------
41 #include <string>
42 //----------------------------------------------------------------------------
43 
44 namespace soma
45 {
46 
48  #if defined(__osf__)
49  typedef unsigned long offset_t;
50  #else
51  typedef unsigned long long offset_t;
52  #endif
53 
63 
64  class DataSource : public virtual carto::RCObject
65  {
66  public:
67  enum Mode
68  {
69  Read = 1,
70  Write = 2,
71  ReadWrite = 3,
72  };
73 
75  {
78  };
79 
80  DataSource();
81  virtual ~DataSource();
82 
84  int mode() const;
85 
86  virtual DataSource* clone() const = 0;
88  virtual int iterateMode() const = 0;
89  virtual bool isOpen() const = 0;
90  virtual bool eof() const;
91  virtual bool operator ! () const;
92  virtual operator bool () const;
93  virtual bool open ( int mode ) = 0;
94  virtual void close() = 0;
95  virtual void flush();
96  virtual offset_t size() const = 0;
97  virtual offset_t at() const = 0;
98  virtual bool at( offset_t pos ) = 0;
99  virtual bool atEnd() const;
100  bool reset();
101  virtual long readBlock( char * data, unsigned long maxlen ) = 0;
102  virtual long writeBlock( const char * data, unsigned long len ) = 0;
103  virtual int getch() = 0;
104  virtual int putch( int ch ) = 0;
105  virtual bool ungetch( int ch ) = 0;
106  virtual bool allowsMemoryMapping() const = 0;
107  virtual std::string url() const;
108 
111  static const carto::rc_ptr<DataSource> none();
112  protected:
113  int _mode;
114  };
115 
116 }
117 
118 #endif
virtual DataSource * clone() const =0
static const carto::rc_ptr< DataSource > none()
An empty ref-counter that is more convenient than calling a constructor of rc_ptr (useful...
virtual long writeBlock(const char *data, unsigned long len)=0
virtual bool eof() const
Abstraction layer for various data sources (file, buffer, socket...).
Definition: datasource.h:64
virtual bool operator!() const
virtual offset_t size() const =0
virtual long readBlock(char *data, unsigned long maxlen)=0
virtual void close()=0
virtual bool allowsMemoryMapping() const =0
virtual bool open(int mode)=0
int mode() const
access mode(s) (read/write): bitwise OR of Mode values
#define soma
Definition: soma_config.h:38
virtual ~DataSource()
virtual bool ungetch(int ch)=0
unsigned long long offset_t
Offsets are 64 bits if supported.
Definition: datasource.h:51
virtual int putch(int ch)=0
virtual std::string url() const
virtual bool isOpen() const =0
virtual int iterateMode() const =0
possible iteration mode(s): bitwise OR of IterateMode values
virtual bool atEnd() const
virtual void flush()
virtual int getch()=0
virtual offset_t at() const =0