pio

package
v0.4.134 Latest Latest
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 Go to latest Published: Nov 27, 2023 License: ISC Imports: 12 Imported by: 0

Documentation

Overview

EofReader is an empty reader returning EOF. Thread-safe

LineReader reads a stream one line per Read invocation.

LineReader reads a stream one line per Read invocation.

ReadWriteCloserSlice is a read-writer with a slice as intermediate storage. thread-safe.

TeeWriter is a writer that copies its writes to one or more other writers.

Index

Constants

This section is empty.

Variables

View Source 
var EofReader io.Reader = &eofReader{}

EofReader is an empty reader returning EOF. Thread-safe

View Source 
var ErrCopyShutdown = errors.New("Copy received Shutdown")
View Source 
var ErrFileAlreadyClosed = errors.New("file alread closed")

On write after close, ErrFileAlreadyClosed is returned. 

if errors.Is(err, pio.ErrFileAlreadyClosed)…
View Source 
var ErrInvalidWrite = errors.New("invalid write result")

errInvalidWrite means that a write returned an impossible count

Functions

func CopyContext added in v0.4.108 

func CopyContext(dst io.Writer, src io.Reader, buf []byte, ctx context.Context) (written int64, err error)

CopyContext is like io.Copy but is cancelable via context

  • CopyContext closes both reader and writer if their runtime type is closable
  • context cancel is on any Read or Write invocation and by parallel close if either reader or writer is closable

func CopyThread added in v0.4.95 

func CopyThread(
	label string, reader io.Reader, writer io.Writer,
	errCh chan<- error, ctx context.Context,
)

CopyThread copies from an io.Reader to an io.Writer.

  • label is used for thread identification on panics
  • errCh receives result and makes thread awaitable
  • if ctx, a CancelContext, is non-nil and error occurs, ctx is cancelled
  • CopyThread itself never fails

func InitWriteCloserToChan 

func InitWriteCloserToChan(wcp *WriteCloserToChan)

func NewReadCloserCallbacker added in v0.4.38 

func NewReadCloserCallbacker(closeCallback func(err error) (e error), readCloser io.ReadCloser) (readCloserCallbacker io.ReadCloser)

func NewTeeWriter added in v0.4.38 

func NewTeeWriter(closeCallback func() (err error), writers ...io.Writer) (teeWriter io.WriteCloser)

TeeWriter is a writer that copies its writes to one or more other writers.

func NewWriteCloserCallbacker added in v0.4.38 

func NewWriteCloserCallbacker(closeCallback func(err error) (e error), writeCloser io.WriteCloser) (writeCloserCallbacker io.WriteCloser)

func NewWriteCloserToChan 

func NewWriteCloserToChan() (writeCloser io.WriteCloser)

func NewWriteCloserToChanLine 

func NewWriteCloserToChanLine(withNewline ...bool) (writeCloser io.WriteCloser)

func NewWriteCloserToString 

func NewWriteCloserToString() io.WriteCloser

NewWriteCloserToString returns an io.WriteCloser that aggregates its oputput in a string. Thread-safe.

Types

type CloserCallbacker added in v0.4.38 

type CloserCallbacker struct {
	// contains filtered or unexported fields
}

CloserCallbacker implements a close callback for io.Closer

func (*CloserCallbacker) Close added in v0.4.38 

func (c *CloserCallbacker) Close(closer io.Closer) (err error)

func (*CloserCallbacker) IsClosed added in v0.4.38 

func (cc *CloserCallbacker) IsClosed() (isClosed bool)

func (*CloserCallbacker) Wait added in v0.4.38 

func (cc *CloserCallbacker) Wait()

type ContextCloser added in v0.4.108 

type ContextCloser struct {
	// contains filtered or unexported fields
}

ContextCloser is an idempotent io.Closer

func NewContextCloser added in v0.4.108 

func NewContextCloser(closer io.Closer) (contextCloser *ContextCloser)

NewContextCloser returns a an idempotent io.Closer

  • closer may be nil
  • panic-free idempotent observable

func (*ContextCloser) Close added in v0.4.108 

func (c *ContextCloser) Close() (err error)

Close closes the io.Closer

  • if Close has already been invoked, noop, no error
  • if io.Closer is nil, noop, no error
  • panic-free idempotent

func (*ContextCloser) IsCloseable added in v0.4.108 

func (c *ContextCloser) IsCloseable() (isCloseable bool)

IsCloseable indicates whether an io.Closer is present that can be closed

type ContextCopier added in v0.4.108 

type ContextCopier struct {
	// contains filtered or unexported fields
}

ContextCopier is an io.Copy cancelable via context

func NewContextCopier added in v0.4.108 

func NewContextCopier(buf ...[]byte) (copier *ContextCopier)

NewContextCopier copies src to dst aborting if context is canceled

  • buf is buffer that can be used
  • if reader implements WriteTo or writer implements ReadFrom, no buffer is required
  • if a buffer is reqiired ans missing, 1 MiB is allocated
  • Copy methods does copying
  • Shutdown method or context cancel aborts Copy in progress
  • if the runtime type of reader or writer is io.Closable, a thread is active during copying

func (*ContextCopier) Copy added in v0.4.134 

func (c *ContextCopier) Copy(
	dst io.Writer,
	src io.Reader,
	ctx context.Context,
) (n int64, err error)

Copy copies from src to dst until end of data, error, Shutdown or context cancel

  • Shutdown method or context cancel aborts copy in progress
  • on context cancel, error returned is context.Canceled
  • on Shutdown, error returned has ErrCopyShutdown
  • if the runtime type of dst or src is io.Closable, a thread is active during copying
  • such reader or writer will be closed

func (*ContextCopier) Shutdown added in v0.4.134 

func (c *ContextCopier) Shutdown()

Shutdown order the thread to exit and wait for its result

  • every Copy invocation will have a Shutdown either by consumer or the deferred copyEnd method

type ContextReader added in v0.4.108 

type ContextReader struct {

	// idempotent pannic-free closer if reader implemented [io.Closer]
	//	- Close() IsClosable()
	ContextCloser
	// contains filtered or unexported fields
}

ContextReader is an io.ReadCloser that aborts on context cancel

  • on context cancel, Read returns error context.Canceled
  • If the runtime type of reader implements io.Close, it ContextReader can close it

func NewContextReader added in v0.4.108 

func NewContextReader(reader io.Reader, ctx context.Context) (contextReader *ContextReader)

NewContextReader returns an io.ReadCloser that aborts on context cancel

  • on context cancel, Read returns error context.Canceled
  • If the runtime type of reader implements io.Close, it can be closed

func (*ContextReader) Read added in v0.4.108 

func (c *ContextReader) Read(p []byte) (n int, err error)

Read is like io.Reader.Read but cancels if the context is canceled

type ContextWriter added in v0.4.108 

type ContextWriter struct {

	// idempotent pannic-free closer if reader implemented [io.Closer]
	//	- Close() IsClosable()
	ContextCloser
	// contains filtered or unexported fields
}

ContextWriter is an io.WriteCloser that aborts on context cancel

  • on context cancel, Write returns error context.Canceled
  • If the runtime type of writer implements io.Close, it ContextWriter can close it

func NewContextWriter added in v0.4.108 

func NewContextWriter(writer io.Writer, ctx context.Context) (contextWriter *ContextWriter)

NewContextWriter returns an io.WriteCloser that aborts on context cancel

  • on context cancel, Write returns error context.Canceled
  • If the runtime type of reader implements io.Close, it can be closed

func (*ContextWriter) Write added in v0.4.108 

func (c *ContextWriter) Write(p []byte) (n int, err error)

Write is like io.Writer.Write but cancels if the context is canceled

type LineReader added in v0.4.38 

type LineReader struct {
	// contains filtered or unexported fields
}

LineReader reads a stream one line per Read invocation.

func NewLineReader added in v0.4.38 

func NewLineReader(reader io.Reader) (lineReader *LineReader)

func (*LineReader) Read added in v0.4.38 

func (rr *LineReader) Read(p []byte) (n int, err error)

Read returns a byte-sequence ending with newline if size of p is sufficient.

  • if size of p is too short, the text will not end with newline
  • if EOF without newline, text has no newline and err is io.EOF

func (*LineReader) ReadLine added in v0.4.38 

func (rr *LineReader) ReadLine(p []byte) (line []byte, isEOF bool, err error)

ReadLine returns full lines, extending p as necessary

  • len(line) is number of bytes
  • max line length 1 MiB
  • line will end with newLine unless 1 MiB or isEOF
  • EOF is returned as isEOF true

type LineWriter added in v0.4.38 

type LineWriter struct {
	// contains filtered or unexported fields
}

func NewLineWriter added in v0.4.38 

func NewLineWriter(writeCloser io.WriteCloser,
	filter func(line *[]byte, isLastLine bool) (skipLine bool, err error)) (lineWriter *LineWriter)

func (*LineWriter) Close added in v0.4.38 

func (wc *LineWriter) Close() (err error)

Close closes

func (*LineWriter) Write added in v0.4.38 

func (wc *LineWriter) Write(p []byte) (n int, err error)

Write saves data in slice and returns all bytes written or ErrFileAlreadyClosed

type ReadCloserCallbacker added in v0.4.38 

type ReadCloserCallbacker struct {
	io.ReadCloser
	CloserCallbacker
}

func (*ReadCloserCallbacker) Close added in v0.4.38 

func (cc *ReadCloserCallbacker) Close() (err error)

type ReadWriteCloserSlice 

type ReadWriteCloserSlice struct {
	// contains filtered or unexported fields
}

ReadWriteCloserSlice is a read-writer with a slice as intermediate storage. thread-safe.

  • Close closes the writer side indicating no further data will be added
  • Write and Close may return error that can be checked: errors.Is(err, pio.ErrFileAlreadyClosed)
  • read will eventually return io.EOF after a Close
  • there are no other errors

func NewReadWriteCloserSlice 

func NewReadWriteCloserSlice() (readWriteCloser *ReadWriteCloserSlice)

func (*ReadWriteCloserSlice) Buffer added in v0.4.95 

func (r *ReadWriteCloserSlice) Buffer() (buffer []byte)

func (*ReadWriteCloserSlice) Close 

func (r *ReadWriteCloserSlice) Close() (err error)

Close closes thw Write part, may return ErrFileAlreadyClosed

func (*ReadWriteCloserSlice) Read 

func (r *ReadWriteCloserSlice) Read(p []byte) (n int, err error)

Read returns at most len(p) bytes read in n and possibly io.EOF

  • Read is blocking
  • n may be less than len(p)
  • if len(p) > 0, non-error return will have n > 0

func (*ReadWriteCloserSlice) Write 

func (r *ReadWriteCloserSlice) Write(p []byte) (n int, err error)

Write saves data in slice and returns all bytes written or ErrFileAlreadyClosed

type TeeWriter added in v0.4.38 

type TeeWriter struct {
	// contains filtered or unexported fields
}

TeeWriter is a writer that copies its writes to one or more other writers.

func (*TeeWriter) Close added in v0.4.38 

func (w *TeeWriter) Close() (err error)

func (*TeeWriter) Write added in v0.4.38 

func (tw *TeeWriter) Write(p []byte) (n int, err error)

type WriteCloserCallbacker added in v0.4.38 

type WriteCloserCallbacker struct {
	io.WriteCloser
	CloserCallbacker
}

func (*WriteCloserCallbacker) Close added in v0.4.38 

func (cc *WriteCloserCallbacker) Close() (err error)

type WriteCloserToChan 

type WriteCloserToChan struct {
	// contains filtered or unexported fields
}

func (*WriteCloserToChan) Ch 

func (wc *WriteCloserToChan) Ch() (readCh <-chan []byte)

func (*WriteCloserToChan) Close 

func (wc *WriteCloserToChan) Close() (err error)

func (*WriteCloserToChan) Write 

func (wc *WriteCloserToChan) Write(p []byte) (n int, err error)

type WriteCloserToChanLine 

type WriteCloserToChanLine struct {
	// contains filtered or unexported fields
}

func (*WriteCloserToChanLine) Ch 

func (wc *WriteCloserToChanLine) Ch() (readCh <-chan string)

func (*WriteCloserToChanLine) Close 

func (wc *WriteCloserToChanLine) Close() (err error)

func (*WriteCloserToChanLine) Write 

func (wc *WriteCloserToChanLine) Write(p []byte) (n int, err error)

type WriteCloserToString 

type WriteCloserToString struct {
	// contains filtered or unexported fields
}

WriteCloserToString is an io.WriteCloser that aggregates its oputput in a string. Thread-safe.

  • the string is available using the Data method.

func (*WriteCloserToString) Close 

func (wc *WriteCloserToString) Close() (err error)

Close should only be invoked once. Close is not required for releasing resources.

func (*WriteCloserToString) Data 

func (wc *WriteCloserToString) Data() (s string)

Data returns current string data

func (*WriteCloserToString) Write 

func (wc *WriteCloserToString) Write(p []byte) (n int, err error)

Write always succeeds

Source Files

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