1 files changed, 0 insertions, 318 deletions
diff --git a/internal/fs/readfile.go b/internal/fs/readfile.go
deleted file mode 100644
index 312447a..0000000
--- a/internal/fs/readfile.go
+++ /dev/null
@@ -1,318 +0,0 @@
-package fs
-
-import (
-	"bufio"
-	"compress/gzip"
-	"github.com/mimecast/dtail/internal/logger"
-	"errors"
-	"io"
-	"os"
-	"regexp"
-	"strings"
-	"sync"
-	"time"
-
-	"github.com/DataDog/zstd"
-)
-
-// Used to tail and filter a local log file.
-type readFile struct {
-	// Various statistics (e.g. regex hit percentage, transfer percentage).
-	stats
-	// Path of log file to tail.
-	filePath string
-	// Only consider all log lines matching this regular expression.
-	re *regexp.Regexp
-	// The glob identifier of the file.
-	globID string
-	// Channel to send a server message to the dtail client
-	serverMessages chan<- string
-	// Signals to stop tailing the log file.
-	stop chan struct{}
-	// Periodically retry reading file.
-	retry bool
-	// Can I skip messages when there are too many?
-	canSkipLines bool
-	// Seek to the EOF before processing file?
-	seekEOF bool
-	// Mutex to control the stopping of the file
-	mutex   *sync.Mutex
-	limiter chan struct{}
-}
-
-// FilePath returns the full file path.
-func (f readFile) FilePath() string {
-	return f.filePath
-}
-
-// Retry reading the file on error?
-func (f readFile) Retry() bool {
-	return f.retry
-}
-
-// Start tailing a log file.
-func (f readFile) Start(lines chan<- LineRead, regex string) error {
-	defer func() {
-		select {
-		case <-f.limiter:
-		default:
-		}
-	}()
-
-	select {
-	case f.limiter <- struct{}{}:
-	default:
-		select {
-		case f.serverMessages <- logger.Warn(f.filePath, f.globID, "Server limit reached. Queuing file..."):
-		case <-f.stop:
-			return nil
-		}
-		f.limiter <- struct{}{}
-	}
-
-	fd, err := os.Open(f.filePath)
-	if err != nil {
-		return err
-	}
-	defer fd.Close()
-
-	if f.seekEOF {
-		fd.Seek(0, io.SeekEnd)
-	}
-
-	rawLines := make(chan []byte, 100)
-	truncate := make(chan struct{})
-
-	var wg sync.WaitGroup
-	wg.Add(1)
-
-	go f.periodicTruncateCheck(truncate)
-	go f.filter(&wg, rawLines, lines, regex)
-
-	err = f.read(fd, rawLines, truncate)
-	close(rawLines)
-	wg.Wait()
-
-	return err
-}
-
-func (f readFile) periodicTruncateCheck(truncate chan struct{}) {
-	for {
-		select {
-		case <-time.After(time.Second * 3):
-			select {
-			case truncate <- struct{}{}:
-			case <-f.stop:
-			}
-		case <-f.stop:
-			return
-		}
-	}
-}
-
-// Stop reading file.
-func (f readFile) Stop() {
-	f.mutex.Lock()
-	defer f.mutex.Unlock()
-
-	select {
-	case <-f.stop:
-		return
-	default:
-	}
-
-	close(f.stop)
-}
-
-func (f readFile) makeReader(fd *os.File) (reader *bufio.Reader, err error) {
-	switch {
-	case strings.HasSuffix(f.FilePath(), ".gz"):
-		fallthrough
-	case strings.HasSuffix(f.FilePath(), ".gzip"):
-		logger.Info(f.FilePath(), "Detected gzip compression format")
-		var gzipReader *gzip.Reader
-		gzipReader, err = gzip.NewReader(fd)
-		if err != nil {
-			return
-		}
-		reader = bufio.NewReader(gzipReader)
-	case strings.HasSuffix(f.FilePath(), ".zst"):
-		logger.Info(f.FilePath(), "Detected zstd compression format")
-		reader = bufio.NewReader(zstd.NewReader(fd))
-	default:
-		reader = bufio.NewReader(fd)
-	}
-
-	return
-}
-
-func (f readFile) read(fd *os.File, rawLines chan []byte, truncate <-chan struct{}) error {
-	reader, err := f.makeReader(fd)
-	if err != nil {
-		return err
-	}
-	rawLine := make([]byte, 0, 512)
-	var offset uint64
-
-	lineLengthThreshold := 1024 * 1024 // 1mb
-	longLineWarning := false
-
-	for {
-		select {
-		case <-truncate:
-			if isTruncated, err := f.truncated(fd); isTruncated {
-				return err
-			}
-			logger.Info(f.filePath, "Current offset", offset)
-
-		case <-f.stop:
-			return nil
-		default:
-		}
-
-		// Read some bytes (max 4k at once as of go 1.12). isPrefix will
-		// be set if line does not fit into 4k buffer.
-		bytes, isPrefix, err := reader.ReadLine()
-
-		if err != nil {
-			// If EOF, sleep a couple of ms and return with nil error.
-			// If other error, return with non-nil error.
-			if err != io.EOF {
-				return err
-			}
-			if !f.seekEOF {
-				logger.Debug(f.FilePath(), "End of file reached")
-				return nil
-			}
-			time.Sleep(time.Millisecond * 100)
-			continue
-		}
-
-		rawLine = append(rawLine, bytes...)
-		offset += uint64(len(bytes))
-
-		if !isPrefix {
-			// last LineRead call returned contend until end of line.
-			rawLine = append(rawLine, '\n')
-			select {
-			case rawLines <- rawLine:
-			case <-f.stop:
-				return nil
-			}
-			rawLine = make([]byte, 0, 512)
-			if longLineWarning {
-				longLineWarning = false
-			}
-			continue
-		}
-
-		// Last LineRead call could not read content until end of line, buffer
-		// was too small. Determine whether we exceed the max line length we
-		// want dtail to send to the client at once. Possibly split up log line
-		// into multiple log lines.
-		if len(rawLine) >= lineLengthThreshold {
-			if !longLineWarning {
-				f.serverMessages <- logger.Warn(f.filePath, "Long log line, splitting into multiple lines")
-				// Only print out one warning per long log line.
-				longLineWarning = true
-			}
-			rawLine = append(rawLine, '\n')
-			select {
-			case rawLines <- rawLine:
-			case <-f.stop:
-				return nil
-			}
-			rawLine = make([]byte, 0, 512)
-		}
-	}
-}
-
-// Filter log lines matching a given regular expression.
-func (f readFile) filter(wg *sync.WaitGroup, rawLines <-chan []byte, lines chan<- LineRead, regex string) {
-	defer wg.Done()
-
-	if regex == "" {
-		regex = "."
-	}
-
-	re, err := regexp.Compile(regex)
-	if err != nil {
-		logger.Error(regex, "Can't compile regex, using '.' instead", err)
-		re = regexp.MustCompile(".")
-	}
-	f.re = re
-
-	for {
-		select {
-		case line, ok := <-rawLines:
-			f.updatePosition()
-			if !ok {
-				return
-			}
-			if filteredLine, ok := f.transmittable(line, len(lines), cap(lines)); ok {
-				select {
-				case lines <- filteredLine:
-				case <-f.stop:
-					return
-				}
-			}
-		}
-	}
-}
-
-func (f readFile) transmittable(line []byte, length, capacity int) (LineRead, bool) {
-	var read LineRead
-
-	if !f.re.Match(line) {
-		f.updateLineNotMatched()
-		f.updateLineNotTransmitted()
-		return read, false
-	}
-	f.updateLineMatched()
-
-	// Can we actually send more messages, channel capacity reached?
-	if f.canSkipLines && length >= capacity {
-		f.updateLineNotTransmitted()
-		return read, false
-	}
-	f.updateLineTransmitted()
-
-	read = LineRead{
-		Content:         line,
-		GlobID:          &f.globID,
-		Count:           f.totalLineCount(),
-		TransmittedPerc: f.transmittedPerc(),
-	}
-
-	return read, true
-}
-
-// Check wether log file is truncated. Returns nil if not.
-func (f readFile) truncated(fd *os.File) (bool, error) {
-	logger.Debug(f.filePath, "File truncation check")
-
-	// Can not seek currently open FD.
-	curPos, err := fd.Seek(0, os.SEEK_CUR)
-	if err != nil {
-		return true, err
-	}
-
-	// Can not open file at original path.
-	pathFd, err := os.Open(f.filePath)
-	if err != nil {
-		return true, err
-	}
-	defer pathFd.Close()
-
-	// Can not seek file at original path.
-	pathPos, err := pathFd.Seek(0, io.SeekEnd)
-	if err != nil {
-		return true, err
-	}
-
-	if curPos > pathPos {
-		return true, errors.New("File got truncated")
-	}
-
-	return false, nil
-}