Remove scanner in favour of readline

pkg/redact/single_line.go

@@ -34,15 +34,6 @@ func NewSingleLineRedactor(re LineRedactor, maskText, path, name string, isDefau
 	return &SingleLineRedactor{scan: scanCompiled, re: compiled, maskText: maskText, filePath: path, redactName: name, isDefault: isDefault}, nil
 }
 
-const (
-	// This is the initial size of the buffer allocated.
-	// Under the hood, an array of size N is allocated in memory
-	BUF_INIT_SIZE = 4096 // 4KB
-
-	// This is the muximum size the buffer can grow to
-	SCANNER_MAX_SIZE = 1024 * 1024 // 1MB
-)
-
 func (r *SingleLineRedactor) Redact(input io.Reader, path string) io.Reader {
 	out, writer := io.Pipe()
 
@@ -58,14 +49,15 @@ func (r *SingleLineRedactor) Redact(input io.Reader, path string) io.Reader {
 
 		substStr := []byte(getReplacementPattern(r.re, r.maskText))
 
-		buf := make([]byte, BUF_INIT_SIZE)
-		scanner := bufio.NewScanner(input)
-		scanner.Buffer(buf, SCANNER_MAX_SIZE)
-
+		reader := bufio.NewReader(input)
 		lineNum := 0
-		for scanner.Scan() {
+		for {
 			lineNum++
-			line := scanner.Bytes()
+			var line []byte
+			line, err = readLine(reader)
+			if err != nil {
+				return
+			}
 
 			// is scan is not nil, then check if line matches scan by lowercasing it
 			if r.scan != nil {
@@ -102,9 +94,6 @@ func (r *SingleLineRedactor) Redact(input io.Reader, path string) io.Reader {
 				})
 			}
 		}
-		if scanErr := scanner.Err(); scanErr != nil {
-			err = scanErr
-		}
 	}()
 	return out
 }