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SEmbeddedStreamReaderWriter Struct Reference

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+ Inheritance diagram for SEmbeddedStreamReaderWriter:
+ Collaboration diagram for SEmbeddedStreamReaderWriter:

Public Member Functions

 SEmbeddedStreamReaderWriter (SNetStorageObjectImpl &impl)
 
ERW_Result Read (void *b, size_t c, size_t *r) override
 Read as many as "count" bytes into a buffer pointed to by the "buf" argument. More...
 
ERW_Result PendingCount (size_t *c) override
 Via parameter "count" (which is guaranteed to be supplied non-NULL) return the number of bytes that are ready to be read from the input device without blocking. More...
 
ERW_Result Write (const void *b, size_t c, size_t *w) override
 Write up to "count" bytes from the buffer pointed to by the "buf" argument onto the output device. More...
 
ERW_Result Flush () override
 Flush pending data (if any) down to the output device. More...
 
void Close () override
 
void Abort () override
 
- Public Member Functions inherited from IReader
virtual ERW_Result Pushback (const void *buf, size_t count, void *del_ptr=0)
 This method gets called by RStream buffer destructor to return buffered yet still unread (from the stream) portion of data back to the device. More...
 
virtual ~IReader ()
 
- Public Member Functions inherited from IWriter
virtual ~IWriter ()
 

Private Attributes

SNetStorageObjectImplm_Impl
 

Detailed Description

Definition at line 41 of file netstorage.cpp.

Constructor & Destructor Documentation

◆ SEmbeddedStreamReaderWriter()

SEmbeddedStreamReaderWriter::SEmbeddedStreamReaderWriter ( SNetStorageObjectImpl impl)
inline

Definition at line 43 of file netstorage.cpp.

Member Function Documentation

◆ Abort()

void SEmbeddedStreamReaderWriter::Abort ( void  )
inlineoverridevirtual

Implements IEmbeddedStreamWriter.

Definition at line 50 of file netstorage.cpp.

References IEmbeddedStreamWriter::Abort(), and m_Impl.

◆ Close()

void SEmbeddedStreamReaderWriter::Close ( void  )
inlineoverridevirtual

Implements IEmbeddedStreamWriter.

Definition at line 49 of file netstorage.cpp.

References IEmbeddedStreamWriter::Close(), and m_Impl.

◆ Flush()

ERW_Result SEmbeddedStreamReaderWriter::Flush ( )
inlineoverridevirtual

Flush pending data (if any) down to the output device.

Implements IWriter.

Definition at line 48 of file netstorage.cpp.

References IWriter::Flush(), and m_Impl.

◆ PendingCount()

ERW_Result SEmbeddedStreamReaderWriter::PendingCount ( size_t *  count)
inlineoverridevirtual

Via parameter "count" (which is guaranteed to be supplied non-NULL) return the number of bytes that are ready to be read from the input device without blocking.

Return eRW_Success if the number of pending bytes has been stored at the location pointed to by "count". Return eRW_NotImplemented if the number cannot be determined. Otherwise, return other eRW_... condition to reflect the problem ("*count" does not need to be updated in the case of non-eRW_Success). Note that if reporting 0 bytes ready, the method may return either both eRW_Success and zero "*count", or return eRW_NotImplemented alone.

Implements IReader.

Definition at line 46 of file netstorage.cpp.

References m_Impl, and IReader::PendingCount().

◆ Read()

ERW_Result SEmbeddedStreamReaderWriter::Read ( void *  buf,
size_t  count,
size_t *  bytes_read 
)
inlineoverridevirtual

Read as many as "count" bytes into a buffer pointed to by the "buf" argument.

Always store the number of bytes actually read (0 if read none) via the pointer "bytes_read", if provided non-NULL. Return non-eRW_Success code if EOF / error condition has been encountered during the operation (some data may have been read, nevertheless, and reflected in "*bytes_read"). Special case: if "count" is passed as 0, then the value of "buf" must be ignored, and no change should be made to the state of the input device (but may return non-eRW_Success to indicate that the input device has already been in an error condition).

Note
Apparently, may not return eRW_Success if hasn't been able to read "count" bytes as requested, and "bytes_read" was provided as NULL.
When returning "*bytes_read" as zero for a non-zero "count" requested, the return status should not indicate eRW_Success.
Warning
"*bytes_read" may never be returned greater than "count".
Attention
It is implementation-dependent whether the call blocks until the entire buffer is read or the call returns when at least some data are available. In general, it is advised that this call is made within a loop that checks for EOF condition and proceeds with the reading until the required amount of data has been retrieved.

Implements IReader.

Definition at line 45 of file netstorage.cpp.

References b, m_Impl, r(), and IReader::Read().

◆ Write()

ERW_Result SEmbeddedStreamReaderWriter::Write ( const void *  buf,
size_t  count,
size_t *  bytes_written 
)
inlineoverridevirtual

Write up to "count" bytes from the buffer pointed to by the "buf" argument onto the output device.

Always store the number of bytes actually written, or 0 if "count" has been passed as 0 ("buf" must be ignored in this case), via the "bytes_written" pointer, if provided non-NULL. Note that the method can return non-eRW_Success in case of an I/O error along with indicating (some) data delivered to the output device (and reflected in "*bytes_written").

Note
Apparently, may not return eRW_Success if hasn't been able to write "count" bytes as requested, and "bytes_written" was passed as NULL.
When returning "*bytes_written" as zero for a non-zero "count" requested, the return status should not indicate eRW_Success.
Warning
"*bytes_written" may never be returned greater than "count".
Attention
It is implementation-dependent whether the call blocks until the entire buffer or only some data has been written out. In general, it is advised that this call is made within a loop that checks for errors and proceeds with the writing until the required amount of data has been sent.

Implements IWriter.

Reimplemented in SIoStreamEmbeddedStreamReaderWriter.

Definition at line 47 of file netstorage.cpp.

References b, m_Impl, and IWriter::Write().

Referenced by SIoStreamEmbeddedStreamReaderWriter::Write().

Member Data Documentation

◆ m_Impl

SNetStorageObjectImpl& SEmbeddedStreamReaderWriter::m_Impl
private

Definition at line 53 of file netstorage.cpp.

Referenced by Abort(), Close(), Flush(), PendingCount(), Read(), and Write().


The documentation for this struct was generated from the following file:
Modified on Fri Sep 20 14:57:56 2024 by modify_doxy.py rev. 669887