SkFILEStream Class Reference

#include <SkStream.h>

Inheritance diagram for SkFILEStream:

Public Member Functions
	SkFILEStream (const char path[]=nullptr)
	SkFILEStream (FILE *file)
	SkFILEStream (FILE *file, size_t size)
	~SkFILEStream () override
bool	isValid () const
void	close ()
size_t	read (void *buffer, size_t size) override
bool	isAtEnd () const override
bool	rewind () override
std::unique_ptr< SkStreamAsset >	duplicate () const
size_t	getPosition () const override
bool	seek (size_t position) override
bool	move (long offset) override
std::unique_ptr< SkStreamAsset >	fork () const
size_t	getLength () const override
Public Member Functions inherited from SkStreamAsset
bool	hasLength () const override
std::unique_ptr< SkStreamAsset >	duplicate () const
std::unique_ptr< SkStreamAsset >	fork () const
Public Member Functions inherited from SkStreamSeekable
std::unique_ptr< SkStreamSeekable >	duplicate () const
bool	hasPosition () const override
std::unique_ptr< SkStreamSeekable >	fork () const
Public Member Functions inherited from SkStreamRewindable
std::unique_ptr< SkStreamRewindable >	duplicate () const
Public Member Functions inherited from SkStream
virtual	~SkStream ()
	SkStream ()
size_t	skip (size_t size)
virtual size_t	peek (void *, size_t) const
bool	readS8 (int8_t *)
bool	readS16 (int16_t *)
bool	readS32 (int32_t *)
bool	readU8 (uint8_t *i)
bool	readU16 (uint16_t *i)
bool	readU32 (uint32_t *i)
bool	readBool (bool *b)
bool	readScalar (SkScalar *)
bool	readPackedUInt (size_t *)
std::unique_ptr< SkStream >	duplicate () const
std::unique_ptr< SkStream >	fork () const
virtual const void *	getMemoryBase ()
virtual sk_sp< SkData >	getData () const

Static Public Member Functions
static std::unique_ptr< SkFILEStream >	Make (const char path[])
Static Public Member Functions inherited from SkStream
static std::unique_ptr< SkStreamAsset >	MakeFromFile (const char path[])

Private Member Functions
SkStreamAsset *	onDuplicate () const override
SkStreamAsset *	onFork () const override

Detailed Description

A stream that wraps a C FILE* file stream.

Definition at line 291 of file SkStream.h.

Constructor & Destructor Documentation

SkFILEStream() [1/3]

SkFILEStream::SkFILEStream ( const char  path[] = nullptr )

explicit

Initialize the stream by calling sk_fopen on the specified path. This internal stream will be closed in the destructor.

Definition at line 190 of file SkStream.cpp.

    : SkFILEStream(path ? sk_fopen(path, kRead_SkFILE_Flag) : nullptr)
{ }

SkFILEStream() [2/3]

SkFILEStream::SkFILEStream ( FILE *  file )

explicit

Initialize the stream with an existing C FILE stream. The current position of the C FILE stream will be considered the beginning of the SkFILEStream and the current seek end of the FILE will be the end. The C FILE stream will be closed in the destructor.

Definition at line 184 of file SkStream.cpp.

    : SkFILEStream(std::shared_ptr<FILE>(file, sk_fclose),
                   file ? sk_fgetsize(file) : 0,
                   file ? sk_ftell(file) : 0)
{ }

SkFILEStream() [3/3]

SkFILEStream::SkFILEStream ( FILE *  file, size_t  size  )

explicit

Initialize the stream with an existing C FILE stream. The current position of the C FILE stream will be considered the beginning of the SkFILEStream and size bytes later will be the end. The C FILE stream will be closed in the destructor.

Definition at line 180 of file SkStream.cpp.

    : SkFILEStream(file, size, file ? sk_ftell(file) : 0)
{ }

~SkFILEStream()

SkFILEStream::~SkFILEStream ( )

override

Definition at line 194 of file SkStream.cpp.

                            {
    this->close();
}

Member Function Documentation

close()

void SkFILEStream::close

(

)

Close this SkFILEStream.

Definition at line 198 of file SkStream.cpp.

                         {
    fFILE.reset();
    fEnd = 0;
    fStart = 0;
    fCurrent = 0;
}

duplicate()

std::unique_ptr< SkStreamAsset > SkFILEStream::duplicate ( ) const

inline

Definition at line 329 of file SkStream.h.

                                                   {
        return std::unique_ptr<SkStreamAsset>(this->onDuplicate());
    }

fork()

std::unique_ptr< SkStreamAsset > SkFILEStream::fork ( ) const

inline

Definition at line 337 of file SkStream.h.

                                              {
        return std::unique_ptr<SkStreamAsset>(this->onFork());
    }

getLength()

size_t SkFILEStream::getLength ( ) const

overridevirtual

Returns the total length of the stream. If this cannot be done, returns 0.

Implements SkStreamAsset.

Definition at line 270 of file SkStream.cpp.

                                     {
    return fEnd - fStart;
}

getPosition()

size_t SkFILEStream::getPosition ( ) const

overridevirtual

Returns the current position in the stream. If this cannot be done, returns 0.

Implements SkStreamSeekable.

Definition at line 236 of file SkStream.cpp.

                                       {
    SkASSERT(fCurrent >= fStart);
    return fCurrent - fStart;
}

isAtEnd()

bool SkFILEStream::isAtEnd ( ) const

overridevirtual

Returns true when all the bytes in the stream have been read. As SkStream represents synchronous I/O, isAtEnd returns false when the final stream length isn't known yet, even when all the bytes available so far have been read. This may return true early (when there are no more bytes to be read) or late (after the first unsuccessful read).

Implements SkStream.

Definition at line 220 of file SkStream.cpp.

                                 {
    if (fCurrent == fEnd) {
        return true;
    }
    return fCurrent >= sk_fgetsize(fFILE.get());
}

isValid()

bool SkFILEStream::isValid ( ) const

inline

Returns true if the current path could be opened.

Definition at line 320 of file SkStream.h.

{ return fFILE != nullptr; }

Make()

static std::unique_ptr< SkFILEStream > SkFILEStream::Make ( const char  path[] )

inlinestatic

Definition at line 314 of file SkStream.h.

                                                               {
        std::unique_ptr<SkFILEStream> stream(new SkFILEStream(path));
        return stream->isValid() ? std::move(stream) : nullptr;
    }

move()

bool SkFILEStream::move ( long  )

overridevirtual

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).

Implements SkStreamSeekable.

Definition at line 246 of file SkStream.cpp.

                                   {
    if (offset < 0) {
        if (offset == std::numeric_limits<long>::min() ||
            !SkTFitsIn<size_t>(-offset) ||
            (size_t) (-offset) >= this->getPosition())
        {
            fCurrent = fStart;
        } else {
            fCurrent += offset;
        }
    } else if (!SkTFitsIn<size_t>(offset)) {
        fCurrent = fEnd;
    } else {
        fCurrent = std::min(SkSafeMath::Add(fCurrent, (size_t) offset), fEnd);
    }
 
    SkASSERT(fCurrent >= fStart && fCurrent <= fEnd);
    return true;
}

onDuplicate()

SkStreamAsset * SkFILEStream::onDuplicate ( ) const

overrideprivatevirtual

Implements SkStreamAsset.

Definition at line 232 of file SkStream.cpp.

                                               {
    return new SkFILEStream(fFILE, fEnd, fStart, fStart);
}

onFork()

SkStreamAsset * SkFILEStream::onFork ( ) const

overrideprivatevirtual

Implements SkStreamAsset.

Definition at line 266 of file SkStream.cpp.

                                          {
    return new SkFILEStream(fFILE, fEnd, fStart, fCurrent);
}

read()

size_t SkFILEStream::read ( void *  buffer, size_t  size  )

overridevirtual

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

buffer	when NULL skip size bytes, otherwise copy size bytes into buffer
size	the number of bytes to skip or copy

Returns

the number of bytes actually read.

Implements SkStream.

Definition at line 205 of file SkStream.cpp.

                                                   {
    if (size > fEnd - fCurrent) {
        size = fEnd - fCurrent;
    }
    size_t bytesRead = size;
    if (buffer) {
        bytesRead = sk_qread(fFILE.get(), buffer, size, fCurrent);
    }
    if (bytesRead == SIZE_MAX) {
        return 0;
    }
    fCurrent += bytesRead;
    return bytesRead;
}

rewind()

bool SkFILEStream::rewind ( )

overridevirtual

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

Implements SkStreamRewindable.

Definition at line 227 of file SkStream.cpp.

                          {
    fCurrent = fStart;
    return true;
}

seek()

bool SkFILEStream::seek ( size_t  )

overridevirtual

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.

Implements SkStreamSeekable.

Definition at line 241 of file SkStream.cpp.

                                       {
    fCurrent = std::min(SkSafeMath::Add(position, fStart), fEnd);
    return true;
}

---

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

• third_party/skia/include/core/SkStream.h
• third_party/skia/src/core/SkStream.cpp