#include <basicio.hpp>
Inheritance diagram for Exiv2::BasicIo:
Public Types | |
typedef std::auto_ptr< BasicIo > | AutoPtr |
BasicIo auto_ptr type. | |
enum | Position { beg, cur, end } |
Seek starting positions. | |
Public Member Functions | |
Creators | |
virtual | ~BasicIo () |
Destructor. | |
Manipulators | |
virtual int | open ()=0 |
Open the IO source using the default access mode. The default mode should allow for reading and writing. | |
virtual int | close ()=0 |
Close the IO source. After closing a BasicIo instance can not be read or written. Closing flushes any unwritten data. It is safe to call close on a closed instance. | |
virtual long | write (const byte *data, long wcount)=0 |
Write data to the IO source. Current IO position is advanced by the number of bytes written. | |
virtual long | write (BasicIo &src)=0 |
Write data that is read from another BasicIo instance to the IO source. Current IO position is advanced by the number of bytes written. | |
virtual int | putb (byte data)=0 |
Write one byte to the IO source. Current IO position is advanced by one byte. | |
virtual DataBuf | read (long rcount)=0 |
Read data from the IO source. Reading starts at the current IO position and the position is advanced by the number of bytes read. | |
virtual long | read (byte *buf, long rcount)=0 |
Read data from the IO source. Reading starts at the current IO position and the position is advanced by the number of bytes read. | |
virtual int | getb ()=0 |
Read one byte from the IO source. Current IO position is advanced by one byte. | |
virtual void | transfer (BasicIo &src)=0 |
Remove all data from this object's IO source and then transfer data from the src BasicIo object into this object. | |
virtual int | seek (long offset, Position pos)=0 |
Move the current IO position. | |
virtual byte * | mmap (bool isWriteable=false)=0 |
Direct access to the IO data. For files, this is done by mapping the file into the process's address space; for memory blocks, this allows direct access to the memory block. | |
virtual int | munmap ()=0 |
Remove a mapping established with mmap(). If the mapped area is writeable, this ensures that changes are written back. | |
Accessors | |
virtual long | tell () const =0 |
Get the current IO position. | |
virtual long | size () const =0 |
Get the current size of the IO source in bytes. | |
virtual bool | isopen () const =0 |
Returns true if the IO source is open, otherwise false. | |
virtual int | error () const =0 |
Returns 0 if the IO source is in a valid state, otherwise nonzero. | |
virtual bool | eof () const =0 |
Returns true if the IO position has reach the end, otherwise false. | |
virtual std::string | path () const =0 |
Return the path to the IO resource. Often used to form comprehensive error messages where only a BasicIo instance is available. | |
virtual BasicIo::AutoPtr | temporary () const =0 |
Returns a temporary data storage location. This is often needed to rewrite an IO source. | |
Protected Member Functions | |
Creators | |
BasicIo () | |
Default Constructor. |
Designed to have semantics and names similar to those of C style FILE* operations. Subclasses should all behave the same so that they can be interchanged.
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Close the IO source. After closing a BasicIo instance can not be read or written. Closing flushes any unwritten data. It is safe to call close on a closed instance.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Read one byte from the IO source. Current IO position is advanced by one byte.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Direct access to the IO data. For files, this is done by mapping the file into the process's address space; for memory blocks, this allows direct access to the memory block.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Remove a mapping established with mmap(). If the mapped area is writeable, this ensures that changes are written back.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Open the IO source using the default access mode. The default mode should allow for reading and writing. This method can also be used to "reopen" an IO source which will flush any unwritten data and reset the IO position to the start. Subclasses may provide custom methods to allow for opening IO sources differently.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Write one byte to the IO source. Current IO position is advanced by one byte.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Read data from the IO source. Reading starts at the current IO position and the position is advanced by the number of bytes read.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Read data from the IO source. Reading starts at the current IO position and the position is advanced by the number of bytes read.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Move the current IO position.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Get the current size of the IO source in bytes.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Get the current IO position.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Returns a temporary data storage location. This is often needed to rewrite an IO source. For example, data may be read from the original IO source, modified in some way, and then saved to the temporary instance. After the operation is complete, the BasicIo::transfer method can be used to replace the original IO source with the modified version. Subclasses are free to return any class that derives from BasicIo.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Remove all data from this object's IO source and then transfer data from the src BasicIo object into this object. The source object is invalidated by this operation and should not be used after this method returns. This method exists primarily to be used with the BasicIo::temporary() method.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Write data that is read from another BasicIo instance to the IO source. Current IO position is advanced by the number of bytes written.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |
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Write data to the IO source. Current IO position is advanced by the number of bytes written.
Implemented in Exiv2::FileIo, and Exiv2::MemIo. |