Skia
2D Graphics Library
SkStreamRewindable Class Referenceabstract

SkStreamRewindable is a SkStream for which rewind and duplicate are required. More...

#include <SkStream.h>

Inheritance diagram for SkStreamRewindable:

Public Member Functions

bool rewind () override=0
 Rewinds to the beginning of the stream. More...
 
std::unique_ptr< SkStreamRewindableduplicate () const
 
virtual size_t read (void *buffer, size_t size)=0
 Reads or skips size number of bytes. More...
 
size_t skip (size_t size)
 Skip size number of bytes. More...
 
virtual size_t peek (void *, size_t) const
 Attempt to peek at size bytes. More...
 
virtual bool isAtEnd () const =0
 Returns true when all the bytes in the stream have been read. More...
 
bool SK_WARN_UNUSED_RESULT readS8 (int8_t *)
 
bool SK_WARN_UNUSED_RESULT readS16 (int16_t *)
 
bool SK_WARN_UNUSED_RESULT readS32 (int32_t *)
 
bool SK_WARN_UNUSED_RESULT readU8 (uint8_t *i)
 
bool SK_WARN_UNUSED_RESULT readU16 (uint16_t *i)
 
bool SK_WARN_UNUSED_RESULT readU32 (uint32_t *i)
 
bool SK_WARN_UNUSED_RESULT readBool (bool *b)
 
bool SK_WARN_UNUSED_RESULT readScalar (SkScalar *)
 
bool SK_WARN_UNUSED_RESULT readPackedUInt (size_t *)
 
std::unique_ptr< SkStreamfork () const
 Duplicates this stream. More...
 
virtual bool hasPosition () const
 Returns true if this stream can report it's current position. More...
 
virtual size_t getPosition () const
 Returns the current position in the stream. More...
 
virtual bool seek (size_t)
 Seeks to an absolute position in the stream. More...
 
virtual bool move (long)
 Seeks to an relative offset in the stream. More...
 
virtual bool hasLength () const
 Returns true if this stream can report it's total length. More...
 
virtual size_t getLength () const
 Returns the total length of the stream. More...
 
virtual const void * getMemoryBase ()
 Returns the starting address for the data. More...
 

Static Public Member Functions

static std::unique_ptr< SkStreamAssetMakeFromFile (const char path[])
 Attempts to open the specified file as a stream, returns nullptr on failure. More...
 

Detailed Description

SkStreamRewindable is a SkStream for which rewind and duplicate are required.

Member Function Documentation

◆ duplicate()

std::unique_ptr<SkStreamRewindable> SkStreamRewindable::duplicate ( ) const
inline

◆ fork()

std::unique_ptr<SkStream> SkStream::fork ( ) const
inlineinherited

Duplicates this stream.

If this cannot be done, returns NULL. The returned stream will be positioned the same as this stream.

◆ getLength()

virtual size_t SkStream::getLength ( ) const
inlinevirtualinherited

Returns the total length of the stream.

If this cannot be done, returns 0.

Reimplemented in SkStreamAsset, SkMemoryStream, and SkFILEStream.

◆ getMemoryBase()

virtual const void* SkStream::getMemoryBase ( )
inlinevirtualinherited

Returns the starting address for the data.

If this cannot be done, returns NULL.

Reimplemented in SkStreamMemory, and SkMemoryStream.

◆ getPosition()

virtual size_t SkStream::getPosition ( ) const
inlinevirtualinherited

Returns the current position in the stream.

If this cannot be done, returns 0.

Reimplemented in SkStreamSeekable, SkMemoryStream, and SkFILEStream.

◆ hasLength()

virtual bool SkStream::hasLength ( ) const
inlinevirtualinherited

Returns true if this stream can report it's total length.

Reimplemented in SkStreamAsset.

◆ hasPosition()

virtual bool SkStream::hasPosition ( ) const
inlinevirtualinherited

Returns true if this stream can report it's current position.

Reimplemented in SkStreamSeekable.

◆ isAtEnd()

virtual bool SkStream::isAtEnd ( ) const
pure virtualinherited

Returns true when all the bytes in the stream have been read.

This may return true early (when there are no more bytes to be read) or late (after the first unsuccessful read).

Implemented in SkMemoryStream, and SkFILEStream.

◆ MakeFromFile()

static std::unique_ptr<SkStreamAsset> SkStream::MakeFromFile ( const char  path[])
staticinherited

Attempts to open the specified file as a stream, returns nullptr on failure.

◆ move()

virtual bool SkStream::move ( long  )
inlinevirtualinherited

Seeks to an relative offset in the stream.

If this cannot be done, returns false. If an attempt is made to move to a position outside the stream, the position will be set to the closest point within the stream (beginning or end).

Reimplemented in SkStreamSeekable, SkMemoryStream, and SkFILEStream.

◆ peek()

virtual size_t SkStream::peek ( void *  ,
size_t   
) const
inlinevirtualinherited

Attempt to peek at size bytes.

If this stream supports peeking, copy min(size, peekable bytes) into buffer, and return the number of bytes copied. If the stream does not support peeking, or cannot peek any bytes, return 0 and leave buffer unchanged. The stream is guaranteed to be in the same visible state after this call, regardless of success or failure.

Parameters
bufferMust not be NULL, and must be at least size bytes. Destination to copy bytes.
sizeNumber of bytes to copy.
Returns
The number of bytes peeked/copied.

Reimplemented in SkMemoryStream.

◆ read()

virtual size_t SkStream::read ( void *  buffer,
size_t  size 
)
pure virtualinherited

Reads or skips size number of bytes.

If buffer == NULL, skip size bytes, return how many were skipped. If buffer != NULL, copy size bytes into buffer, return how many were copied.

Parameters
bufferwhen NULL skip size bytes, otherwise copy size bytes into buffer
sizethe number of bytes to skip or copy
Returns
the number of bytes actually read.

Implemented in SkMemoryStream, and SkFILEStream.

◆ readBool()

bool SK_WARN_UNUSED_RESULT SkStream::readBool ( bool *  b)
inlineinherited

◆ readPackedUInt()

bool SK_WARN_UNUSED_RESULT SkStream::readPackedUInt ( size_t *  )
inherited

◆ readS16()

bool SK_WARN_UNUSED_RESULT SkStream::readS16 ( int16_t *  )
inherited

◆ readS32()

bool SK_WARN_UNUSED_RESULT SkStream::readS32 ( int32_t *  )
inherited

◆ readS8()

bool SK_WARN_UNUSED_RESULT SkStream::readS8 ( int8_t *  )
inherited

◆ readScalar()

bool SK_WARN_UNUSED_RESULT SkStream::readScalar ( SkScalar )
inherited

◆ readU16()

bool SK_WARN_UNUSED_RESULT SkStream::readU16 ( uint16_t *  i)
inlineinherited

◆ readU32()

bool SK_WARN_UNUSED_RESULT SkStream::readU32 ( uint32_t *  i)
inlineinherited

◆ readU8()

bool SK_WARN_UNUSED_RESULT SkStream::readU8 ( uint8_t *  i)
inlineinherited

◆ rewind()

bool SkStreamRewindable::rewind ( )
overridepure virtual

Rewinds to the beginning of the stream.

Returns true if the stream is known to be at the beginning after this call returns.

Reimplemented from SkStream.

Implemented in SkMemoryStream, and SkFILEStream.

◆ seek()

virtual bool SkStream::seek ( size_t  )
inlinevirtualinherited

Seeks to an absolute position in the stream.

If this cannot be done, returns false. If an attempt is made to seek past the end of the stream, the position will be set to the end of the stream.

Reimplemented in SkStreamSeekable, SkMemoryStream, and SkFILEStream.

◆ skip()

size_t SkStream::skip ( size_t  size)
inlineinherited

Skip size number of bytes.

Returns
the actual number bytes that could be skipped.

The documentation for this class was generated from the following file: