diff --git a/revid/Revid.go b/revid/Revid.go index c3c55b24..fbb9b1af 100644 --- a/revid/Revid.go +++ b/revid/Revid.go @@ -46,7 +46,7 @@ import ( "bitbucket.org/ausocean/av/generator" "bitbucket.org/ausocean/av/parser" - "bitbucket.org/ausocean/av/ringbuffer" + "bitbucket.org/ausocean/av/ring" "bitbucket.org/ausocean/av/rtmp" ) @@ -57,6 +57,8 @@ const ( mp2tMaxPackets = 2016 * clipDuration // # first multiple of 7 and 8 greater than 2000 ringBufferSize = 500 ringBufferElementSize = 150000 + writeTimeout = 10 * time.Millisecond + readTimeout = 10 * time.Millisecond httpTimeOut = 5 // s packetsPerFrame = 7 bitrateTime = 60 // s @@ -98,7 +100,7 @@ type Revid interface { type revid struct { ffmpegPath string tempDir string - ringBuffer ringbuffer.RingBuffer + ringBuffer *ring.Buffer config Config isRunning bool outputFile *os.File @@ -113,7 +115,7 @@ type revid struct { setupInput func() error setupOutput func() error getFrame func() []byte - sendClip func(clip []byte) error + sendClip func(*ring.Chunk) error rtmpInst rtmp.Session mutex sync.Mutex sendMutex sync.Mutex @@ -127,7 +129,7 @@ func NewRevid(config Config) (r *revid, err error) { r = new(revid) r.mutex = sync.Mutex{} r.sendMutex = sync.Mutex{} - r.ringBuffer = ringbuffer.NewRingBuffer(ringBufferSize, ringBufferElementSize) + r.ringBuffer = ring.NewBuffer(ringBufferSize, ringBufferElementSize, writeTimeout) err = r.changeState(config) if err != nil { r = nil @@ -161,8 +163,8 @@ func (r *revid) changeState(config Config) error { switch r.config.Output { case File: - r.sendClip = r.sendClipToFile r.setupOutput = r.setupOutputForFile + r.sendClip = r.sendClipToFile case FfmpegRtmp: r.setupOutput = r.setupOutputForFfmpegRtmp r.sendClip = r.sendClipToFfmpegRtmp @@ -339,59 +341,40 @@ done: func (r *revid) packClips() { clipSize := 0 packetCount := 0 - outputChanFullFlag := false for r.isRunning { - // Get some memory from the ring buffer for out clip - var clip []byte - var err error - if clip, err = r.ringBuffer.Get(); err != nil && r.isRunning { - if !outputChanFullFlag { + select { + // TODO: This is temporary, need to work out how to make this work + // for cases when there is not packetisation. + case frame := <-r.generator.GetOutputChan(): + lenOfFrame := len(frame) + if lenOfFrame > ringBufferElementSize { + r.Log(Warning, fmt.Sprintf("Frame was too big: %v bytes, getting another one!", lenOfFrame)) + frame = r.getFrame() + lenOfFrame = len(frame) + } + _, err := r.ringBuffer.Write(frame) + if err != nil { r.Log(Error, err.Error()) - r.Log(Warning, "Clearing output chan!") - outputChanFullFlag = true + if err == ring.ErrDropped { + r.Log(Warning, fmt.Sprintf("dropped %d byte frame", len(frame))) + } } - for clip, err = r.ringBuffer.Get(); err != nil && r.isRunning; { - time.Sleep(time.Duration(10) * time.Millisecond) - clip, err = r.ringBuffer.Get() + packetCount++ + clipSize += lenOfFrame + fpcAsInt, err := strconv.Atoi(r.config.FramesPerClip) + if err != nil { + r.Log(Error, "Frames per clip not quite right! Defaulting to 1!") + r.config.FramesPerClip = "1" } - r.Log(Debug, "Finally got mem from ringbuffer!") - outputChanFullFlag = false + if packetCount >= fpcAsInt { + r.ringBuffer.Flush() + clipSize = 0 + packetCount = 0 + continue + } + default: + time.Sleep(time.Duration(5) * time.Millisecond) } - - for r.isRunning { - select { - // TODO: This is temporary, need to work out how to make this work - // for cases when there is not packetisation. - case frame := <-(r.generator.GetOutputChan()): - lenOfFrame := len(frame) - if lenOfFrame > ringBufferElementSize { - r.Log(Warning, fmt.Sprintf("Frame was too big: %v bytes, getting another one!", lenOfFrame)) - frame = r.getFrame() - lenOfFrame = len(frame) - } - upperBound := clipSize + lenOfFrame - copy(clip[clipSize:upperBound], frame) - packetCount++ - clipSize += lenOfFrame - fpcAsInt, err := strconv.Atoi(r.config.FramesPerClip) - if err != nil { - r.Log(Error, "Frames per clip not quite right! Defaulting to 1!") - r.config.FramesPerClip = "1" - } - if packetCount >= fpcAsInt { - if err := r.ringBuffer.DoneWriting(clipSize); err != nil { - r.Log(Error, err.Error()) - r.Log(Warning, "Dropping clip!") - } - clipSize = 0 - packetCount = 0 - goto finishedWithClip - } - default: - time.Sleep(time.Duration(5) * time.Millisecond) - } - } - finishedWithClip: } } @@ -405,122 +388,136 @@ func (r *revid) outputClips() { for r.isRunning { // Here we slow things down as much as we can to decrease cpu usage switch { - case r.ringBuffer.GetNoOfElements() < 2: + case r.ringBuffer.Len() < 2: delay++ time.Sleep(time.Duration(delay) * time.Millisecond) case delay > 0: delay-- } // If the ringbuffer has something we can read and send off - if clip, err := r.ringBuffer.Read(); err == nil && r.isRunning { - bytes += len(clip) - r.Log(Detail, "About to send") - err2 := r.sendClip(clip) - if err2 == nil { - r.Log(Detail, "Sent clip") + chunk, err := r.ringBuffer.Next(readTimeout) + if err != nil || !r.isRunning { + if err == io.EOF { + break } + continue + } - if r.isRunning && err2 != nil && len(clip) > 11 { - r.Log(Debug, "Send failed! Trying again") - // Try and send again - err2 = r.sendClip(clip) + bytes += chunk.Len() + r.Log(Detail, "About to send") + err = r.sendClip(chunk) + if err == nil { + r.Log(Detail, "Sent clip") + } - // if there's still an error we try and reconnect, unless we're stopping - for r.isRunning && err2 != nil { - r.Log(Debug, "Send failed a again! Trying to reconnect...") - time.Sleep(time.Duration(sendFailedDelay) * time.Millisecond) - r.Log(Error, err2.Error()) + if r.isRunning && err != nil && chunk.Len() > 11 { + r.Log(Debug, "Send failed! Trying again") + // Try and send again + err = r.sendClip(chunk) - if r.config.Output == NativeRtmp { - r.Log(Debug, "Ending current rtmp session...") - r.rtmpInst.Close() - } - if r.ringBuffer.Full() { - r.Log(Debug, "Flushing incoming data...") - r.flushData() - } - - if r.config.Output == NativeRtmp { - r.Log(Info, "Restarting rtmp session...") - r.rtmpInst.StartSession() - } - - r.Log(Debug, "Trying to send again with new connection...") - // and if the ring buffer is full then we flush the incoming data - err2 = r.sendClip(clip) - } - } - - r.Log(Detail, "Done reading that clip from ringbuffer...") - // let the ringbuffer know that we're done with the memory we grabbed when - // we call ringBuffer.Get() - if err := r.ringBuffer.DoneReading(); err != nil { + // if there's still an error we try and reconnect, unless we're stopping + for r.isRunning && err != nil { + r.Log(Debug, "Send failed a again! Trying to reconnect...") + time.Sleep(time.Duration(sendFailedDelay) * time.Millisecond) r.Log(Error, err.Error()) + + if r.config.Output == NativeRtmp { + r.Log(Debug, "Ending current rtmp session...") + r.rtmpInst.Close() + } + + if r.config.Output == NativeRtmp { + r.Log(Info, "Restarting rtmp session...") + r.rtmpInst.StartSession() + } + + r.Log(Debug, "Trying to send again with new connection...") + r.sendClip(chunk) // TODO(kortschak): Log these errors? } - // Log some information regarding bitrate and ring buffer size if it's time - now = time.Now() - deltaTime := now.Sub(prevTime) - if deltaTime > time.Duration(bitrateTime)*time.Second { - r.currentBitrate = int64(float64(bytes*8) / float64(deltaTime/1e9)) - r.Log(Debug, fmt.Sprintf("Bitrate: %v bits/s\n", r.currentBitrate)) - r.Log(Debug, fmt.Sprintf("Ring buffer size: %v\n", r.ringBuffer.GetNoOfElements())) - prevTime = now - bytes = 0 - } + } + + chunk.Close() // ring.Chunk is an io.Closer, but Close alwats returns nil. + r.Log(Detail, "Done reading that clip from ringbuffer...") + + // Log some information regarding bitrate and ring buffer size if it's time + now = time.Now() + deltaTime := now.Sub(prevTime) + if deltaTime > time.Duration(bitrateTime)*time.Second { + r.currentBitrate = int64(float64(bytes*8) / float64(deltaTime/1e9)) + r.Log(Debug, fmt.Sprintf("Bitrate: %v bits/s\n", r.currentBitrate)) + r.Log(Debug, fmt.Sprintf("Ring buffer size: %v\n", r.ringBuffer.Len())) + prevTime = now + bytes = 0 } } r.Log(Info, "Not outputting clips anymore!") } // senClipToFile writes the passed clip to a file -func (r *revid) sendClipToFile(clip []byte) error { +func (r *revid) sendClipToFile(clip *ring.Chunk) error { r.sendMutex.Lock() - defer r.sendMutex.Unlock() - _, err := r.outputFile.Write(clip) - if err != nil { - return err - } - return nil + _, err := clip.WriteTo(r.outputFile) + r.sendMutex.Unlock() + return err } // sendClipToHTTP takes a clip and an output url and posts through http. -func (r *revid) sendClipToHTTP(clip []byte) error { - r.sendMutex.Lock() +func (r *revid) sendClipToHTTP(clip *ring.Chunk) error { defer r.sendMutex.Unlock() + r.sendMutex.Lock() + timeout := time.Duration(httpTimeOut * time.Second) client := http.Client{Timeout: timeout} - url := r.config.HttpAddress + strconv.Itoa(len(clip)) - r.Log(Debug, fmt.Sprintf("Posting %s (%d bytes)\n", url, len(clip))) - resp, err := client.Post(url, "video/mp2t", bytes.NewReader(clip)) + url := r.config.HttpAddress + strconv.Itoa(clip.Len()) + + // FIXME(kortschak): This is necessary because Post takes + // an io.Reader as a parameter and closes it if it is an + // io.Closer (which *ring.Chunk is), ... and because we + // use a method value for dispatching the sendClip work. + // So to save work in this case, sendClip should be made + // a proper method with a behaviour switch based on a + // revid field so that we can prepare these bytes only + // once for each clip (reusing a buffer field? or tt + // might be work using a sync.Pool for the bodies). + post := bytes.NewBuffer(make([]byte, 0, clip.Len())) + _, err := clip.WriteTo(post) + if err != nil { + return fmt.Errorf("Error buffering: %v", err) + } + + r.Log(Debug, fmt.Sprintf("Posting %s (%d bytes)\n", url, clip.Len())) + resp, err := client.Post(url, "video/mp2t", post) if err != nil { return fmt.Errorf("Error posting to %s: %s", url, err) } defer resp.Body.Close() + body, err := ioutil.ReadAll(resp.Body) if err == nil { r.Log(Debug, fmt.Sprintf("%s\n", body)) } else { r.Log(Error, err.Error()) } + return nil } // sendClipToFfmpegRtmp sends the clip over the current rtmp connection using // an ffmpeg process. -func (r *revid) sendClipToFfmpegRtmp(clip []byte) (err error) { +func (r *revid) sendClipToFfmpegRtmp(clip *ring.Chunk) error { r.sendMutex.Lock() - defer r.sendMutex.Unlock() - _, err = r.ffmpegStdin.Write(clip) - return + _, err := clip.WriteTo(r.ffmpegStdin) + r.sendMutex.Unlock() + return err } // sendClipToLibRtmp send the clip over the current rtmp connection using the // c based librtmp library -func (r *revid) sendClipToLibRtmp(clip []byte) (err error) { +func (r *revid) sendClipToLibRtmp(clip *ring.Chunk) error { r.sendMutex.Lock() - defer r.sendMutex.Unlock() - err = r.rtmpInst.Write(clip) - return + _, err := clip.WriteTo(r.rtmpInst) + r.sendMutex.Unlock() + return err } // setupOutputForFfmpegRtmp sets up output to rtmp using an ffmpeg process diff --git a/ringbuffer/Readme.md b/ring/README.md similarity index 81% rename from ringbuffer/Readme.md rename to ring/README.md index 7f112c29..3738922b 100644 --- a/ringbuffer/Readme.md +++ b/ring/README.md @@ -1,14 +1,14 @@ # Readme -The package av provides ... +Package ring provides a ring buffer of io.ReadWriters. # Author -Saxon Nelson-Milton +Dan Kortschak # License -ringbuffer is Copyright (C) 2017 the Australian Ocean Lab (AusOcean) +ring is Copyright (C) 2017 the Australian Ocean Lab (AusOcean) It is free software: you can redistribute it and/or modify them under the terms of the GNU General Public License as published by the diff --git a/ring/ring.go b/ring/ring.go new file mode 100644 index 00000000..40ae3be7 --- /dev/null +++ b/ring/ring.go @@ -0,0 +1,277 @@ +/* +NAME + ring.go - a structure that encapsulates a Buffer datastructure with conccurency + functionality + +DESCRIPTION + See Readme.md + +AUTHOR + Dan Kortschak + +LICENSE + ring.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean) + + It is free software: you can redistribute it and/or modify them + under the terms of the GNU General Public License as published by the + Free Software Foundation, either version 3 of the License, or (at your + option) any later version. + + It is distributed in the hope that it will be useful, but WITHOUT + ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + You should have received a copy of the GNU General Public License + along with revid in gpl.txt. If not, see http://www.gnu.org/licenses. +*/ + +// Package ring provides a ring buffer of io.ReadWriters. +package ring + +import ( + "errors" + "io" + "time" +) + +var ( + ErrTimeout = errors.New("ring: buffer cycle timeout") + ErrDropped = errors.New("ring: dropped old write") + ErrStall = errors.New("ring: unable to dump old write") + ErrTooLong = errors.New("ring: write to long for buffer element") +) + +// Buffer implements a ring buffer. +// +// The buffer has a writable head and a readable tail with a queue from the head +// to the tail. Concurrent read a write operations are safe. +type Buffer struct { + head, tail *Chunk + full, empty chan *Chunk + timeout time.Duration +} + +// NewBuffer returns a Buffer with len elements of the given size. The timeout +// parameter specifies how long a write operation will wait before failing with +// a temporary timeout error. +func NewBuffer(len, size int, timeout time.Duration) *Buffer { + if len <= 0 || size <= 0 { + return nil + } + b := Buffer{ + full: make(chan *Chunk, len), + empty: make(chan *Chunk, len), + timeout: timeout, + } + for i := 0; i < len; i++ { + b.empty <- newChunk(make([]byte, 0, size)) + } + return &b +} + +// Len returns the number of full buffer elements. +func (b *Buffer) Len() int { + return len(b.full) +} + +// Write writes the bytes in b to the next current or next available element of the ring buffer +// it returns the number of bytes written and any error. +// If no element can be gained within the timeout or stolen from the queue, ErrStall is returned +// and if the len(p) is greater than the buffer's element size, ErrTooLong is returned. If a +// write was successful but a previous write was dropped, ErrDropped is returned. +// +// Write is safe to use concurrently with Read, but may not be used concurrently with another +// write operation. +func (b *Buffer) Write(p []byte) (int, error) { + var dropped bool + if b.head == nil { + timer := time.NewTimer(b.timeout) + select { + case <-timer.C: + select { + case b.head = <-b.full: + b.head.reset() + dropped = true + default: + // This should never happen. + return 0, ErrStall + } + case b.head = <-b.empty: + timer.Stop() + } + } + if len(p) > b.head.cap() { + return 0, ErrTooLong + } + if len(p) > b.head.cap()-b.head.Len() { + b.full <- b.head + b.head = nil + return b.Write(p) + } + n, err := b.head.write(p) + if b.head.cap()-b.head.Len() == 0 { + b.full <- b.head + b.head = nil + } + if dropped && err == nil { + err = ErrDropped + } + return n, err +} + +// Flush puts the currently writing element of the buffer into the queue for reading. Flush +// is idempotent. +// +// Flush is safe to use concurrently with Read, but may not be used concurrently with another +// another write operation. +func (b *Buffer) Flush() { + if b.head == nil { + return + } + b.full <- b.head + b.head = nil +} + +// Close closes the buffer. The buffer may not be written to after a call to close, but can +// be drained by calls to Read. +// +// Flush is safe to use concurrently with Read, but may not be used concurrently with another +// another write operation. +func (b *Buffer) Close() error { + b.Flush() + close(b.full) + return nil +} + +// Next gets the next element from the queue ready for reading, returning ErrTimeout if no +// element is available within the timeout. If the Buffer has been closed Next returns io.EOF. +// +// Is it the responsibility of the caller to close the returned Chunk. +// +// Next is safe to use concurrently with write operations, but may not be used concurrently with +// another Read call or Next call. A goroutine calling Next must not call Flush or Close. +func (b *Buffer) Next(timeout time.Duration) (*Chunk, error) { + if b.tail == nil { + timer := time.NewTimer(timeout) + var ok bool + select { + case <-timer.C: + return nil, ErrTimeout + case b.tail, ok = <-b.full: + timer.Stop() + if !ok { + return nil, io.EOF + } + } + } + b.tail.owner = b + return b.tail, nil +} + +// Read reads bytes from the current tail of the ring buffer into p and returns the number of +// bytes read and any error. +// +// Read is safe to use concurrently with write operations, but may not be used concurrently with +// another Read call or Next call. A goroutine calling Read must not call Flush or Close. +func (b *Buffer) Read(p []byte) (int, error) { + if b.tail == nil { + return 0, io.EOF + } + n, err := b.tail.read(p) + if b.tail.Len() == 0 { + b.tail.reset() + b.empty <- b.tail + b.tail = nil + } + return n, err +} + +// Chunk is a simplified version of byte buffer without the capacity to grow beyond the +// buffer's original cap, and a modified WriteTo method that allows multiple calls without +// consuming the buffered data. +type Chunk struct { + buf []byte + off int + owner *Buffer +} + +func newChunk(buf []byte) *Chunk { + return &Chunk{buf: buf[:0]} +} + +// Len returns the number of bytes held in the chunk. +func (b *Chunk) Len() int { + return len(b.buf) - b.off +} + +func (b *Chunk) cap() int { + return cap(b.buf) +} + +func (b *Chunk) reset() { + b.buf = b.buf[:0] + b.off = 0 +} + +func (b *Chunk) write(p []byte) (n int, err error) { + if len(p) > cap(b.buf)-len(b.buf) { + err = ErrTooLong + } + l := len(b.buf) + m := l + len(p) + if m > cap(b.buf) { + m = cap(b.buf) + } + b.buf = b.buf[:m] + n = copy(b.buf[l:], p) + return n, err +} + +func (b *Chunk) read(p []byte) (n int, err error) { + if b.Len() <= 0 { + if len(p) == 0 { + return 0, nil + } + return 0, io.EOF + } + n = copy(p, b.buf[b.off:]) + b.off += n + return n, nil +} + +// WriteTo writes data to w until there's no more data to write or when an error occurs. +// The return value n is the number of bytes written. Any error encountered during the +// write is also returned. Repeated called to WriteTo will write the same data until +// the Chunk's Close method is called. +// +// WriteTo will panic if the Chunk has not been obtained through a call to Buffer.Next or +// has been closed. WriteTo must be used in the same goroutine as the call to Next. +func (b *Chunk) WriteTo(w io.Writer) (n int64, err error) { + if b.owner == nil || b.owner.tail != b { + panic("ring: invalid use of ring buffer chunk") + } + _n, err := w.Write(b.buf) + if _n > len(b.buf) { + panic("ring: invalid byte count") + } + if _n != len(b.buf) { + return int64(_n), io.ErrShortWrite + } + return int64(_n), nil +} + +// Close closes the Chunk, reseting its data and releasing it back to the Buffer. A Chunk +// may not be used after it has been closed. Close must be used in the same goroutine as +// the call to Next. +func (b *Chunk) Close() error { + if b.owner == nil || b.owner.tail != b { + panic("ring: invalid use of ring buffer chunk") + } + b.reset() + b.owner.tail = nil + empty := b.owner.empty + b.owner = nil + empty <- b + return nil +} diff --git a/ring/ring_test.go b/ring/ring_test.go new file mode 100644 index 00000000..13270fd3 --- /dev/null +++ b/ring/ring_test.go @@ -0,0 +1,489 @@ +/* +NAME + ring_test.go - a test suite adopting the golang testing library to test functionality of the + RingBuffer structure + +DESCRIPTION + See README.md + +AUTHOR + Dan Kortschak + +LICENSE + ring_test.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean) + + It is free software: you can redistribute it and/or modify them + under the terms of the GNU General Public License as published by the + Free Software Foundation, either version 3 of the License, or (at your + option) any later version. + + It is distributed in the hope that it will be useful, but WITHOUT + ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + You should have received a copy of the GNU General Public License + along with revid in gpl.txt. If not, see http://www.gnu.org/licenses. +*/ + +package ring + +import ( + "bytes" + "io" + "io/ioutil" + "reflect" + "strings" + "sync" + "testing" + "time" +) + +var roundTripTests = []struct { + name string + + len int + size int + timeout time.Duration + nextTimeout time.Duration + + data [][]string + readDelay time.Duration + writeDelay time.Duration +}{ + { + name: "happy", + len: 2, size: 50, + timeout: 100 * time.Millisecond, + nextTimeout: 100 * time.Millisecond, + + data: [][]string{ + {"frame1", "frame2", "frame3", "frame4"}, + {"frame5", "frame6"}, + {"frame5", "frame6", "frame7"}, + {"frame8", "frame9", "frame10"}, + {"frame11"}, + {"frame12", "frame13"}, + {"frame14", "frame15", "frame16", "frame17"}, + }, + }, + { + name: "slow write", + len: 2, size: 50, + timeout: 100 * time.Millisecond, + nextTimeout: 100 * time.Millisecond, + + data: [][]string{ + {"frame1", "frame2", "frame3", "frame4"}, + {"frame5", "frame6"}, + {"frame5", "frame6", "frame7"}, + {"frame8", "frame9", "frame10"}, + {"frame11"}, + {"frame12", "frame13"}, + {"frame14", "frame15", "frame16", "frame17"}, + }, + writeDelay: 500 * time.Millisecond, + }, + { + name: "slow read", + len: 2, size: 50, + timeout: 100 * time.Millisecond, + nextTimeout: 100 * time.Millisecond, + + data: [][]string{ + {"frame1", "frame2", "frame3", "frame4"}, + {"frame5", "frame6"}, + {"frame5", "frame6", "frame7"}, + {"frame8", "frame9", "frame10"}, + {"frame11"}, + {"frame12", "frame13"}, + {"frame14", "frame15", "frame16", "frame17"}, + }, + readDelay: 500 * time.Millisecond, + }, +} + +func TestRoundTrip(t *testing.T) { + const maxTimeouts = 100 + for _, test := range roundTripTests { + b := NewBuffer(test.len, test.size, test.timeout) + var wg sync.WaitGroup + wg.Add(2) + go func() { + defer wg.Done() + for _, c := range test.data { + var dropped int + for _, f := range c { + time.Sleep(test.writeDelay) // Simulate slow data capture. + _, err := b.Write([]byte(f)) + switch err { + case nil: + dropped = 0 + case ErrDropped: + if dropped > maxTimeouts { + t.Errorf("too many write drops for %q", test.name) + return + } + dropped++ + default: + t.Errorf("unexpected write error for %q: %v", test.name, err) + return + } + } + b.Flush() + } + b.Close() + }() + go func() { + buf := make([]byte, 1<<10) + defer wg.Done() + var got []string + var timeouts int + elements: + for { + _, err := b.Next(test.nextTimeout) + switch err { + case nil: + timeouts = 0 + case ErrTimeout: + if timeouts > maxTimeouts { + t.Errorf("too many timeouts for %q", test.name) + return + } + timeouts++ + case io.EOF: + break elements + default: + t.Errorf("unexpected read error for %q: %v", test.name, err) + return + } + reads: + for { + n, err := b.Read(buf) + if n != 0 { + time.Sleep(test.readDelay) // Simulate slow data processing. + got = append(got, string(buf[:n])) + } + switch err { + case nil: + case io.EOF: + break reads + default: + t.Errorf("unexpected read error for %q: %v", test.name, err) + return + } + } + } + var want []string + for _, c := range test.data { + want = append(want, strings.Join(c, "")) + } + if test.readDelay == 0 { + if !reflect.DeepEqual(got, want) { + t.Errorf("unexpected round-trip result for %q:\ngot: %#v\nwant:%#v", test.name, got, want) + } + } else { + // We may have dropped writes in this case. + // So just check that we can consume every + // received element with reference to what + // was sent. + // TODO(kortschak): Check that the number of + // missing elements matches the number of + // dropped writes. + var sidx, ridx int + var recd string + for ridx, recd = range got { + for ; sidx < len(want); sidx++ { + if recd == want[sidx] { + break + } + } + } + if ridx != len(got)-1 { + t.Errorf("unexpected round-trip result for %q (unexplained element received):\ngot: %#v\nwant:%#v", test.name, got, want) + } + } + }() + wg.Wait() + } +} + +func TestRoundTripWriterTo(t *testing.T) { + const maxTimeouts = 100 + for _, test := range roundTripTests { + b := NewBuffer(test.len, test.size, test.timeout) + var wg sync.WaitGroup + wg.Add(2) + go func() { + defer wg.Done() + for _, c := range test.data { + var dropped int + for _, f := range c { + time.Sleep(test.writeDelay) // Simulate slow data capture. + _, err := b.Write([]byte(f)) + switch err { + case nil: + dropped = 0 + case ErrDropped: + if dropped > maxTimeouts { + t.Errorf("too many write drops for %q", test.name) + return + } + dropped++ + default: + t.Errorf("unexpected write error for %q: %v", test.name, err) + return + } + } + b.Flush() + } + b.Close() + }() + go func() { + var buf bytes.Buffer + defer wg.Done() + var got []string + var timeouts int + elements: + for { + chunk, err := b.Next(test.nextTimeout) + switch err { + case nil: + timeouts = 0 + case ErrTimeout: + if timeouts > maxTimeouts { + t.Errorf("too many timeouts for %q", test.name) + return + } + timeouts++ + continue + case io.EOF: + break elements + default: + t.Errorf("unexpected read error for %q: %v", test.name, err) + return + } + + n, err := chunk.WriteTo(&buf) + if n != 0 { + time.Sleep(test.readDelay) // Simulate slow data processing. + got = append(got, buf.String()) + buf.Reset() + } + if err != nil { + t.Errorf("unexpected writeto error for %q: %v", test.name, err) + return + } + err = chunk.Close() + if err != nil { + t.Errorf("unexpected close error for %q: %v", test.name, err) + return + } + } + var want []string + for _, c := range test.data { + want = append(want, strings.Join(c, "")) + } + if test.readDelay == 0 { + if !reflect.DeepEqual(got, want) { + t.Errorf("unexpected round-trip result for %q:\ngot: %#v\nwant:%#v", test.name, got, want) + } + } else { + // We may have dropped writes in this case. + // So just check that we can consume every + // received element with reference to what + // was sent. + // TODO(kortschak): Check that the number of + // missing elements matches the number of + // dropped writes. + var sidx, ridx int + var recd string + for ridx, recd = range got { + for ; sidx < len(want); sidx++ { + if recd == want[sidx] { + break + } + } + } + if ridx != len(got)-1 { + t.Errorf("unexpected round-trip result for %q (unexplained element received):\ngot: %#v\nwant:%#v", test.name, got, want) + } + } + }() + wg.Wait() + } +} + +func BenchmarkRoundTrip(b *testing.B) { + const ( + maxTimeouts = 100 + + len = 50 + size = 150e3 + timeout = 10 * time.Millisecond + + frameLen = 30e3 + + writeDelay = 20 * time.Millisecond + readDelay = 50 * time.Millisecond + ) + + // Allocated prior to timer reset since it is an + // amortised cost. + rb := NewBuffer(len, size, timeout) + + var wg sync.WaitGroup + wg.Add(1) + go func() { + defer wg.Done() + var timeouts int + elements: + for { + _, err := rb.Next(timeout) + switch err { + case nil: + timeouts = 0 + case ErrTimeout: + if timeouts > maxTimeouts { + b.Error("too many timeouts") + return + } + timeouts++ + case io.EOF: + break elements + default: + b.Errorf("unexpected read error: %v", err) + return + } + + _, err = ioutil.ReadAll(rb) + time.Sleep(readDelay) // Simulate slow data processing. + if err != nil { + b.Errorf("unexpected read error: %v", err) + return + } + } + }() + + data := make([]byte, frameLen) + + b.ResetTimer() + b.SetBytes(frameLen) + + var dropped int + for i := 0; i < b.N; i++ { + time.Sleep(writeDelay) // Simulate slow data capture. + _, err := rb.Write(data) + switch err { + case nil: + dropped = 0 + case ErrDropped: + if dropped > maxTimeouts { + b.Error("too many write drops") + return + } + dropped++ + default: + b.Errorf("unexpected write error: %v", err) + return + } + } + + rb.Close() + + wg.Wait() +} + +func BenchmarkRoundTripWriterTo(b *testing.B) { + const ( + maxTimeouts = 100 + + len = 50 + size = 150e3 + timeout = 10 * time.Millisecond + + frameLen = 30e3 + + writeDelay = 20 * time.Millisecond + readDelay = 50 * time.Millisecond + ) + + // Allocated prior to timer reset since it is an + // amortised cost. + rb := NewBuffer(len, size, timeout) + + // This is hoisted here to ensure the allocation + // is not counted since this is outside the control + // of the ring buffer. + buf := bytes.NewBuffer(make([]byte, 0, size+1)) + + var wg sync.WaitGroup + wg.Add(1) + go func() { + defer wg.Done() + var timeouts int + elements: + for { + chunk, err := rb.Next(timeout) + switch err { + case nil: + timeouts = 0 + case ErrTimeout: + if timeouts > maxTimeouts { + b.Error("too many timeouts") + return + } + timeouts++ + continue + case io.EOF: + break elements + default: + b.Errorf("unexpected read error: %v", err) + return + } + + n, err := chunk.WriteTo(buf) + if n != 0 { + time.Sleep(readDelay) // Simulate slow data processing. + buf.Reset() + } + if err != nil { + b.Errorf("unexpected writeto error: %v", err) + return + } + err = chunk.Close() + if err != nil { + b.Errorf("unexpected close error: %v", err) + return + } + } + }() + + data := make([]byte, frameLen) + + b.ResetTimer() + b.SetBytes(frameLen) + + var dropped int + for i := 0; i < b.N; i++ { + time.Sleep(writeDelay) // Simulate slow data capture. + _, err := rb.Write(data) + switch err { + case nil: + dropped = 0 + case ErrDropped: + if dropped > maxTimeouts { + b.Error("too many write drops") + return + } + dropped++ + default: + b.Errorf("unexpected write error: %v", err) + return + } + } + + rb.Close() + + wg.Wait() +} diff --git a/ringbuffer/RingBuffer.go b/ringbuffer/RingBuffer.go deleted file mode 100644 index 7a077aff..00000000 --- a/ringbuffer/RingBuffer.go +++ /dev/null @@ -1,209 +0,0 @@ -/* -NAME - RingBuffer.go - a structure that encapsulates a RingBuffer datastructure with conccurency - functionality - -DESCRIPTION - See Readme.md - -AUTHOR - Saxon Nelson-Milton - -LICENSE - RingBuffer.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean) - - It is free software: you can redistribute it and/or modify them - under the terms of the GNU General Public License as published by the - Free Software Foundation, either version 3 of the License, or (at your - option) any later version. - - It is distributed in the hope that it will be useful, but WITHOUT - ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - for more details. - - You should have received a copy of the GNU General Public License - along with revid in gpl.txt. If not, see [GNU licenses](http://www.gnu.org/licenses). -*/ - -package ringbuffer - -import ( - "errors" - "sync" -) - -/* -RingBuffer aims to provide functionality of a RingBuffer data structure. -It may be used in concurrent routines. -*/ - -type RingBuffer interface { - Get() ([]byte, error) - DoneWriting(size int) error - Read() ([]byte, error) - DoneReading() error - IsReadable() bool - IsWritable() bool - GetNoOfElements() int - Full() bool -} - -func (rb *ringBuffer) GetNoOfElements() int { - return rb.noOfElements -} - -// ringBuffer implements the RingBuffer interface -type ringBuffer struct { - dataMemory [][]byte - sizeMemory []int - size int - noOfElements int - first int - last int - currentlyWriting bool - currentlyReading bool - mutex sync.Mutex - full bool -} - -/* -New returns a pointer to a newly allocated RingBuffer with the parameters specified. -It initialises fields and allocates the required dataMemory. -*/ -func NewRingBuffer(bufferSize int, elementSize int) (rb *ringBuffer) { - if bufferSize <= 0 || elementSize <= 0 { - return nil - } - rb = new(ringBuffer) - rb.dataMemory = make([][]byte, bufferSize) - for i := range rb.dataMemory { - rb.dataMemory[i] = make([]byte, elementSize) - } - rb.sizeMemory = make([]int, bufferSize) - rb.size = bufferSize - rb.noOfElements = 0 - rb.first = -1 - rb.last = -1 - rb.currentlyWriting = false - rb.currentlyReading = false - rb.mutex = sync.Mutex{} - rb.full = false - return -} - -/* -Get provides the address to the next empty element in the RingBuffer. -An error is returned if the buffer is full, or there has already been -a call to Get without an accompanying call to DoneWriting. -*/ -func (rb *ringBuffer) Get() ([]byte, error) { - rb.mutex.Lock() - defer rb.mutex.Unlock() - if !rb.IsWritable() { - rb.full = true - return nil, errors.New("Buffer full!") - } - rb.full = false - var nextlast int - if !rb.currentlyWriting { - rb.currentlyWriting = true - nextlast = rb.last + 1 - if nextlast == rb.size { - nextlast = 0 - } - } else { - nextlast = rb.last - } - return rb.dataMemory[nextlast], nil -} - -/* -DoneWriting let's the RingBuffer know that we have finished writing to the -address recieved by a call to Get, and also let's the buffer know how much -data was written. An Error is thrown if there was not an initial call to Get. -*/ -func (rb *ringBuffer) DoneWriting(size int) error { - rb.mutex.Lock() - defer rb.mutex.Unlock() - if !rb.currentlyWriting { - return errors.New("DoneWriting called without initial call to Get!") - } - if rb.first == -1 { - rb.first++ - } - rb.last++ - if rb.last == rb.size { - rb.last = 0 - } - rb.sizeMemory[rb.last] = size - rb.noOfElements++ - rb.currentlyWriting = false - return nil -} - -/* -Read returns a slice containing the next element in the ring buffer and -thereafter considers it empty and can be used for latter writing. The address -of the data is returned, as well as the size of the data contained at this -address. An error is returned if the buffer is empty, or there has been a -second call to Read before a call to DoneReading. -*/ -func (rb *ringBuffer) Read() ([]byte, error) { - rb.mutex.Lock() - defer rb.mutex.Unlock() - if !rb.IsReadable() { - return nil, errors.New("Buffer is empty, nothing to read!") - } - if rb.currentlyReading { - return nil, errors.New("Second call to Read! Call DoneReading first!") - } - rb.currentlyReading = true - return rb.dataMemory[rb.first][:rb.sizeMemory[rb.first]], nil -} - -/* -DoneReading informs the buffer that we have finished with the address -provided by Read. The buffer can now consider this address to be empty. -An error is returned if there was no initial call to Read. -*/ -func (rb *ringBuffer) DoneReading() error { - rb.mutex.Lock() - defer rb.mutex.Unlock() - if !rb.currentlyReading { - return errors.New("DoneReading called but no initial call to Read!") - } - rb.first++ - if rb.first == rb.size { - rb.first = 0 - } - rb.noOfElements-- - rb.currentlyReading = false - return nil -} - -func (rb *ringBuffer) Full() bool { - return rb.full -} - -/* -IsReadable returns true if it is possible to read from the buffer, i.e. if -it is not empty. -*/ -func (rb *ringBuffer) IsReadable() bool { - if rb.first == -1 || rb.noOfElements == 0 { - return false - } - return true -} - -/* -IsWritable returns true if it is possible to write to the buffer, i.e. if -it is not full. -*/ -func (rb *ringBuffer) IsWritable() bool { - if rb.noOfElements == rb.size { - return false - } - return true -} diff --git a/ringbuffer/RingBuffer_test.go b/ringbuffer/RingBuffer_test.go deleted file mode 100644 index 11849a04..00000000 --- a/ringbuffer/RingBuffer_test.go +++ /dev/null @@ -1,178 +0,0 @@ -/* -NAME - RingBuffer_test.go - a test suite adopting the golang testing library to test functionality of the - RingBuffer structure - -DESCRIPTION - See Readme.md - -AUTHOR - Saxon Nelson-Milton - -LICENSE - RingBuffer_test.go is Copyright (C) 2017 the Australian Ocean Lab (AusOcean) - - It is free software: you can redistribute it and/or modify them - under the terms of the GNU General Public License as published by the - Free Software Foundation, either version 3 of the License, or (at your - option) any later version. - - It is distributed in the hope that it will be useful, but WITHOUT - ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - for more details. - - You should have received a copy of the GNU General Public License - along with revid in gpl.txt. If not, see [GNU licenses](http://www.gnu.org/licenses). -*/ - -package ringbuffer - -import ( - "fmt" - "testing" - "time" -) - -// Parameters used over the testing -const ( - testBufferSize = 10 - testElementSize = 1 - testOverFlowSize = 2 - testDataSize = 1 - testConcurrencyBufferSize = 1000 -) - -// Types of actions, assertions and test ends -const ( - testWrite = 0 - testDoneWriting = 1 - testRead = 2 - testDoneReading = 3 - testEnd = 4 - assertNoError = 5 - assertError = 6 -) - -// Strings to help with test fail messages -const ( - noErrorFailMessage = "Should have got error!" - falseErrorFailMessage = "Should not have got error: %v" - atMessage = " Series: %v" -) - -// Pointer to the ringbuffer we will be testing -var rb *ringBuffer - -// Call when the a test array has the wrong format -func wrongFmt() { - fmt.Println("Test has wrong format!") -} - -// Test that the Make method correctly allocates memory for arbitrary buffer -// size of 10 and arbitrary element size of 10 -func TestMake(t *testing.T) { - rb = NewRingBuffer(testBufferSize, testElementSize) - if len(rb.dataMemory) != testBufferSize { - t.Errorf("Len of buffer is wrong!") - } - if len(rb.dataMemory[0]) != testElementSize { - t.Errorf("Len of individual element is wrong!") - } -} - -// Format: { , , , ..., , } -var tests = [][]int{ - {testBufferSize, assertError, testDoneWriting, testEnd}, - {testBufferSize, assertNoError, testWrite, testDoneWriting, testEnd}, - {testBufferSize, assertError, testDoneReading, testEnd}, - {testBufferSize, assertError, testRead, testEnd}, - {testBufferSize, assertError, testWrite, testWrite, testEnd}, - {testBufferSize, assertNoError, testWrite, testDoneWriting, testRead, - testDoneReading, testEnd}, - {testBufferSize, assertNoError, testWrite, testDoneWriting, testWrite, - testDoneWriting, testRead, testDoneReading, testRead, testDoneReading, - testEnd}, - {testBufferSize, assertError, testWrite, testDoneWriting, testRead, - testDoneReading, testRead, testDoneReading, testEnd}, - {testOverFlowSize, assertError, testWrite, testDoneWriting, testWrite, testDoneWriting, - testWrite, testDoneWriting, testEnd}, - {testOverFlowSize, assertNoError, testWrite, testDoneWriting, testWrite, testDoneWriting, - testRead, testDoneReading, testWrite, testDoneWriting, testEnd}, - {testOverFlowSize, assertError, testWrite, testDoneWriting, testWrite, testDoneWriting, - testRead, testDoneReading, testWrite, testDoneWriting, testWrite, - testDoneWriting, testEnd}, - {testBufferSize, assertError, testWrite, testDoneWriting, testWrite, - testDoneWriting, testRead, testRead, testEnd}, -} - -// Tests series of actions performed by the ring buffer defined in array tests -func TestAllSorts(t *testing.T) { - for i := range tests { - rb = NewRingBuffer(tests[i][0], testElementSize) - var err error - for j := 2; tests[i][j] != testEnd; j++ { - var newErr error - switch tests[i][j] { - case testWrite: - _, newErr = rb.Get() - case testDoneWriting: - newErr = rb.DoneWriting(testDataSize) - case testRead: - _, newErr = rb.Read() - case testDoneReading: - newErr = rb.DoneReading() - default: - wrongFmt() - } - if err == nil { - err = newErr - } - } - switch tests[i][1] { - case assertError: - if err == nil { - t.Errorf(noErrorFailMessage+atMessage, i) - } - case assertNoError: - if err != nil { - t.Errorf(falseErrorFailMessage+atMessage, err, i) - } - default: - wrongFmt() - } - } -} - -// Let's see if we can do concurrency. (tip: run as: go test -race) to see -// any data race issues. We will continously write and read at concurrently -// time for a second -func TestConcurrency1(t *testing.T) { - rb = NewRingBuffer(testConcurrencyBufferSize, testElementSize) - go func() { - for i := 0; i < 100; i++ { - if data, err1 := rb.Read(); data != nil { - err2 := rb.DoneReading() - if err1 != nil { - t.Errorf(falseErrorFailMessage, err1) - } - if err2 != nil { - t.Errorf(falseErrorFailMessage, err2) - } - } - } - }() - go func() { - for i := 0; i < 100; i++ { - _, err1 := rb.Get() - err2 := rb.DoneWriting(testDataSize) - if err1 != nil { - t.Errorf(falseErrorFailMessage, err1) - } - if err2 != nil { - t.Errorf(falseErrorFailMessage, err2) - } - } - }() - time.Sleep(1000 * time.Millisecond) -} diff --git a/ringbuffer/gpl.txt b/ringbuffer/gpl.txt deleted file mode 100644 index 42d4133c..00000000 --- a/ringbuffer/gpl.txt +++ /dev/null @@ -1,674 +0,0 @@ - GNU GENERAL PUBLIC LICENSE - Version 3, 29 June 2007 - - Copyright (C) 2007 Free Software Foundation, Inc. - Everyone is permitted to copy and distribute verbatim copies - of this license document, but changing it is not allowed. - - Preamble - - The GNU General Public License is a free, copyleft license for -software and other kinds of works. - - The licenses for most software and other practical works are designed -to take away your freedom to share and change the works. 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If not, see . - -Also add information on how to contact you by electronic and paper mail. - - If the program does terminal interaction, make it output a short -notice like this when it starts in an interactive mode: - - Copyright (C) - This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. - This is free software, and you are welcome to redistribute it - under certain conditions; type `show c' for details. - -The hypothetical commands `show w' and `show c' should show the appropriate -parts of the General Public License. Of course, your program's commands -might be different; for a GUI interface, you would use an "about box". - - You should also get your employer (if you work as a programmer) or school, -if any, to sign a "copyright disclaimer" for the program, if necessary. -For more information on this, and how to apply and follow the GNU GPL, see -. - - The GNU General Public License does not permit incorporating your program -into proprietary programs. If your program is a subroutine library, you -may consider it more useful to permit linking proprietary applications with -the library. If this is what you want to do, use the GNU Lesser General -Public License instead of this License. But first, please read -. diff --git a/rtmp/rtmp.go b/rtmp/rtmp.go index 784f1a94..0ddf5e48 100644 --- a/rtmp/rtmp.go +++ b/rtmp/rtmp.go @@ -49,7 +49,7 @@ import ( // Session provides an interface for sending flv tags over rtmp. type Session interface { StartSession() error - Write([]byte) error + Write([]byte) (int, error) Close() error } @@ -85,14 +85,14 @@ func (s *session) StartSession() error { } // Write writes a frame (flv tag) to the rtmp connection -func (s *session) Write(data []byte) error { +func (s *session) Write(data []byte) (int, error) { if s.rtmp == nil { - return errors.New("rtmp: attempt to write to non-running session") + return 0, errors.New("rtmp: attempt to write to non-running session") } if C.write_frame(s.rtmp, (*C.char)(unsafe.Pointer(&data[0])), C.uint(len(data))) != 0 { - return errors.New("RTMP write error! Check rtmp log for details!") + return 0, errors.New("RTMP write error! Check rtmp log for details!") } - return nil + return len(data), nil } // Close terminates the rtmp connection