From 89fc9d86c727aa8dc80232b461a7903a3c16d10e Mon Sep 17 00:00:00 2001
From: Přemysl Janouch
Date: Fri, 12 Apr 2019 23:10:42 +0200
Subject: Cleanup, improve communication while printing
---
ql/ql.go | 425 +++++----------------------------------------------------
ql/ql_linux.go | 212 ++++++++++++++++++++++++++++
ql/status.go | 206 ++++++++++++++++++++++++++++
3 files changed, 449 insertions(+), 394 deletions(-)
create mode 100644 ql/ql_linux.go
create mode 100644 ql/status.go
(limited to 'ql')
diff --git a/ql/ql.go b/ql/ql.go
index f7a23dc..ec84656 100644
--- a/ql/ql.go
+++ b/ql/ql.go
@@ -8,54 +8,11 @@ package ql
// http://www.undocprint.org/formats/communication_protocols/ieee_1284
import (
- "errors"
- "fmt"
"image"
- "io"
- "log"
- "os"
- "path/filepath"
"regexp"
"strings"
- "syscall"
- "time"
- "unsafe"
)
-// #include
-import "C"
-
-// -----------------------------------------------------------------------------
-
-func _IOC(dir, typ, nr, size int) uintptr {
- return (uintptr(dir) << C._IOC_DIRSHIFT) |
- (uintptr(typ) << C._IOC_TYPESHIFT) |
- (uintptr(nr) << C._IOC_NRSHIFT) |
- (uintptr(size) << C._IOC_SIZESHIFT)
-}
-
-const (
- iocnrGetDeviceID = 1
-)
-
-// lpiocGetDeviceID reads the IEEE-1284 Device ID string of a printer.
-func lpiocGetDeviceID(fd uintptr) ([]byte, error) {
- var buf [1024]byte
- if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd,
- _IOC(C._IOC_READ, 'P', iocnrGetDeviceID, len(buf)),
- uintptr(unsafe.Pointer(&buf))); err != 0 {
- return nil, err
- }
-
- // In theory it might get trimmed along the way.
- length := int(buf[0])<<8 | int(buf[1])
- if 2+length > len(buf) {
- return buf[2:], errors.New("the device ID string got trimmed")
- }
-
- return buf[2 : 2+length], nil
-}
-
// -----------------------------------------------------------------------------
var deviceIDRegexp = regexp.MustCompile(
@@ -96,14 +53,6 @@ func (id deviceID) FindFirst(key, abbreviation string) string {
// -----------------------------------------------------------------------------
-type Printer struct {
- File *os.File
- Manufacturer string
- Model string
- LastStatus *Status
- MediaInfo *MediaInfo
-}
-
func compatible(id deviceID) bool {
for _, commandSet := range id.Find("COMMAND SET", "CMD") {
if commandSet == "PT-CBP" {
@@ -113,118 +62,6 @@ func compatible(id deviceID) bool {
return false
}
-// Open finds and initializes the first USB printer found supporting
-// the appropriate protocol. Returns nil if no printer could be found.
-func Open() (*Printer, error) {
- // Linux usblp module, located in /drivers/usb/class/usblp.c
- paths, err := filepath.Glob("/dev/usb/lp[0-9]*")
- if err != nil {
- return nil, err
- }
- for _, candidate := range paths {
- f, err := os.OpenFile(candidate, os.O_RDWR, 0)
- if err != nil {
- continue
- }
- // Filter out obvious non-printers.
- deviceID, err := lpiocGetDeviceID(f.Fd())
- if err != nil {
- f.Close()
- continue
- }
- parsedID := parseIEEE1284DeviceID(deviceID)
- // Filter out printers that wouldn't understand the protocol.
- if !compatible(parsedID) {
- f.Close()
- continue
- }
- return &Printer{
- File: f,
- Manufacturer: parsedID.FindFirst("MANUFACTURER", "MFG"),
- Model: parsedID.FindFirst("MODEL", "MDL"),
- }, nil
- }
- return nil, nil
-}
-
-// Initialize initializes the printer for further operations.
-func (p *Printer) Initialize() error {
- // Clear the print buffer.
- invalidate := make([]byte, 400)
- if _, err := p.File.Write(invalidate); err != nil {
- return err
- }
-
- // Initialize.
- if _, err := p.File.WriteString("\x1b\x40"); err != nil {
- return err
- }
-
- // Flush any former responses in the printer's queue.
- //
- // I'm not sure if this is necessary, or rather whether the kernel driver
- // does any buffering that could cause data to be returned at this point.
- /*
- var dummy [32]byte
- for {
- if _, err := f.Read(dummy[:]); err == io.EOF {
- break
- }
- }
- */
-
- return nil
-}
-
-var errTimeout = errors.New("timeout")
-var errInvalidRead = errors.New("invalid read")
-
-// pollStatusBytes waits for the printer to send a status packet and returns
-// it as raw data.
-func (p *Printer) pollStatusBytes(
- timeout time.Duration) (status [32]byte, err error) {
- start, n := time.Now(), 0
- for {
- if n, err = p.File.Read(status[:]); err == io.EOF {
- time.Sleep(10 * time.Millisecond)
- } else if err != nil {
- return status, err
- } else if n < 32 {
- return status, errInvalidRead
- } else {
- return status, nil
- }
- if time.Now().Sub(start) > timeout {
- return status, errTimeout
- }
- }
-}
-
-// Request new status information from the printer. The printer
-// must be in an appropriate mode, i.e. on-line and not currently printing.
-func (p *Printer) UpdateStatus() error {
- // Request status information.
- if _, err := p.File.WriteString("\x1b\x69\x53"); err != nil {
- return err
- }
-
- // Retrieve status information.
- status, err := p.pollStatusBytes(time.Second)
- if err != nil {
- p.LastStatus = nil
- return err
- }
-
- s := Status(status)
- p.LastStatus = &s
- return nil
-}
-
-// Close closes the underlying file.
-func (p *Printer) Close() error {
- return p.File.Close()
-}
-
// -----------------------------------------------------------------------------
type mediaSize struct {
@@ -278,30 +115,35 @@ func GetMediaInfo(widthMM, lengthMM int) *MediaInfo {
// -----------------------------------------------------------------------------
+const (
+ printBytes = 90
+ printPins = printBytes * 8
+)
+
// makeBitmapData converts an image to the printer's raster format.
-func makeBitmapData(src image.Image, offset, length int) (data []byte) {
+func makeBitmapData(src image.Image, margin, length int) (data []byte) {
bounds := src.Bounds()
- pixels := [720]bool{}
+ if bounds.Dy() > length {
+ bounds.Max.Y = bounds.Min.Y + length
+ }
+ if bounds.Dx() > printPins-margin {
+ bounds.Max.X = bounds.Min.X + printPins
+ }
+
+ pixels := [printPins]bool{}
for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
length--
- if length <= 0 {
- break
- }
- off := offset
+ // The graphics needs to be inverted horizontally, iterating backwards.
+ offset := margin
for x := bounds.Max.X - 1; x >= bounds.Min.X; x-- {
- if off >= len(pixels) {
- break
- }
-
- // TODO: Anything to do with the ColorModel?
r, g, b, a := src.At(x, y).RGBA()
- pixels[off] = r == 0 && g == 0 && b == 0 && a != 0
- off++
+ pixels[offset] = r == 0 && g == 0 && b == 0 && a >= 0x8000
+ offset++
}
- data = append(data, 'g', 0x00, 90)
- for i := 0; i < 90; i++ {
+ data = append(data, 'g', 0x00, printBytes)
+ for i := 0; i < printBytes; i++ {
var b byte
for j := 0; j < 8; j++ {
b <<= 1
@@ -313,17 +155,20 @@ func makeBitmapData(src image.Image, offset, length int) (data []byte) {
}
}
for ; length > 0; length-- {
- data = append(data, 'g', 0x00, 90)
- data = append(data, make([]byte, 90)...)
+ data = append(data, 'g', 0x00, printBytes)
+ data = append(data, make([]byte, printBytes)...)
}
return
}
-func (p *Printer) makePrintData(image image.Image) (data []byte) {
+func makePrintData(status *Status, image image.Image) (data []byte) {
mediaInfo := GetMediaInfo(
- p.LastStatus.MediaWidthMM(),
- p.LastStatus.MediaLengthMM(),
+ status.MediaWidthMM(),
+ status.MediaLengthMM(),
)
+ if mediaInfo == nil {
+ return nil
+ }
// Raster mode.
// Should be the only supported mode for QL-800.
@@ -339,12 +184,12 @@ func (p *Printer) makePrintData(image image.Image) (data []byte) {
}
mediaType := byte(0x0a)
- if p.LastStatus.MediaLengthMM() != 0 {
+ if status.MediaLengthMM() != 0 {
mediaType = byte(0x0b)
}
data = append(data, 0x1b, 0x69, 0x7a, 0x02|0x04|0x40|0x80, mediaType,
- byte(p.LastStatus.MediaWidthMM()), byte(p.LastStatus.MediaLengthMM()),
+ byte(status.MediaWidthMM()), byte(status.MediaLengthMM()),
byte(dy), byte(dy>>8), byte(dy>>16), byte(dy>>24), 0, 0x00)
// Auto cut, each 1 label.
@@ -355,7 +200,7 @@ func (p *Printer) makePrintData(image image.Image) (data []byte) {
// Not sure what it means, doesn't seem to have any effect to turn it off.
data = append(data, 0x1b, 0x69, 0x4b, 0x08)
- if p.LastStatus.MediaLengthMM() != 0 {
+ if status.MediaLengthMM() != 0 {
// 3mm margins along the direction of feed. 0x23 = 35 dots, the minimum.
data = append(data, 0x1b, 0x69, 0x64, 0x23, 0x00)
} else {
@@ -373,211 +218,3 @@ func (p *Printer) makePrintData(image image.Image) (data []byte) {
// Print command with feeding.
return append(data, 0x1a)
}
-
-func (p *Printer) Print(image image.Image) error {
- data := p.makePrintData(image)
-
- // Print the prepared data.
- if _, err := p.File.Write(data); err != nil {
- return err
- }
-
- // TODO: We specifically need to wait for a transition to the receiving
- // state, and try to figure out something from the statuses.
- // We may also receive an error status instead of the transition to
- // the printing state. Or even after it.
- start, b := time.Now(), [32]byte{}
- for {
- if n, err := p.File.Read(b[:]); err == io.EOF {
- time.Sleep(100 * time.Millisecond)
- } else if err != nil {
- return err
- } else if n < 32 {
- return errors.New("invalid read")
- } else {
- status := Status(b)
- log.Printf("status\n%s", &status)
- }
- if time.Now().Sub(start) > 3*time.Second {
- break
- }
- }
- return nil
-}
-
-// -----------------------------------------------------------------------------
-
-// Status is a decoder for the status packed returned by the printer.
-type Status [32]byte
-
-func (s *Status) MediaWidthMM() int { return int(s[10]) }
-func (s *Status) MediaLengthMM() int { return int(s[17]) }
-
-func decodeBitfieldErrors(b byte, errors [8]string) []string {
- var result []string
- for i := uint(0); i < 8; i++ {
- if b&(1<
+import "C"
+
+// -----------------------------------------------------------------------------
+
+func _IOC(dir, typ, nr, size int) uintptr {
+ return (uintptr(dir) << C._IOC_DIRSHIFT) |
+ (uintptr(typ) << C._IOC_TYPESHIFT) |
+ (uintptr(nr) << C._IOC_NRSHIFT) |
+ (uintptr(size) << C._IOC_SIZESHIFT)
+}
+
+const (
+ iocnrGetDeviceID = 1
+)
+
+// lpiocGetDeviceID reads the IEEE-1284 Device ID string of a printer.
+func lpiocGetDeviceID(fd uintptr) ([]byte, error) {
+ var buf [1024]byte
+ if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd,
+ _IOC(C._IOC_READ, 'P', iocnrGetDeviceID, len(buf)),
+ uintptr(unsafe.Pointer(&buf))); err != 0 {
+ return nil, err
+ }
+
+ // In theory it might get trimmed along the way.
+ length := int(buf[0])<<8 | int(buf[1])
+ if 2+length > len(buf) {
+ return buf[2:], errors.New("the device ID string got trimmed")
+ }
+
+ return buf[2 : 2+length], nil
+}
+
+// -----------------------------------------------------------------------------
+
+type Printer struct {
+ File *os.File
+ Manufacturer string
+ Model string
+
+ LastStatus *Status
+ MediaInfo *MediaInfo
+
+ // StatusNotify is called whenever we receive a status packet.
+ StatusNotify func(*Status)
+}
+
+// Open finds and initializes the first USB printer found supporting
+// the appropriate protocol. Returns nil if no printer could be found.
+func Open() (*Printer, error) {
+ // Linux usblp module, located in /drivers/usb/class/usblp.c
+ paths, err := filepath.Glob("/dev/usb/lp[0-9]*")
+ if err != nil {
+ return nil, err
+ }
+ for _, candidate := range paths {
+ f, err := os.OpenFile(candidate, os.O_RDWR, 0)
+ if err != nil {
+ continue
+ }
+ // Filter out obvious non-printers.
+ deviceID, err := lpiocGetDeviceID(f.Fd())
+ if err != nil {
+ f.Close()
+ continue
+ }
+ parsedID := parseIEEE1284DeviceID(deviceID)
+ // Filter out printers that wouldn't understand the protocol.
+ if !compatible(parsedID) {
+ f.Close()
+ continue
+ }
+ return &Printer{
+ File: f,
+ Manufacturer: parsedID.FindFirst("MANUFACTURER", "MFG"),
+ Model: parsedID.FindFirst("MODEL", "MDL"),
+ }, nil
+ }
+ return nil, nil
+}
+
+// Initialize initializes the printer for further operations.
+func (p *Printer) Initialize() error {
+ // Clear the print buffer.
+ invalidate := make([]byte, 400)
+ if _, err := p.File.Write(invalidate); err != nil {
+ return err
+ }
+
+ // Initialize.
+ if _, err := p.File.WriteString("\x1b\x40"); err != nil {
+ return err
+ }
+
+ // Flush any former responses in the printer's queue.
+ //
+ // I'm not sure if this is necessary, or rather whether the kernel driver
+ // does any buffering that could cause data to be returned at this point.
+ /*
+ var dummy [32]byte
+ for {
+ if _, err := f.Read(dummy[:]); err == io.EOF {
+ break
+ }
+ }
+ */
+
+ return nil
+}
+
+var errTimeout = errors.New("timeout")
+var errInvalidRead = errors.New("invalid read")
+
+func (p *Printer) updateStatus(status Status) {
+ p.LastStatus = &status
+ if p.StatusNotify != nil {
+ p.StatusNotify(p.LastStatus)
+ }
+}
+
+// pollStatusBytes waits for the printer to send a status packet and returns
+// it as raw data.
+func (p *Printer) pollStatusBytes(
+ timeout time.Duration) (*Status, error) {
+ start, buf := time.Now(), [32]byte{}
+ for {
+ if n, err := p.File.Read(buf[:]); err == io.EOF {
+ time.Sleep(10 * time.Millisecond)
+ } else if err != nil {
+ return nil, err
+ } else if n < 32 {
+ return nil, errInvalidRead
+ } else {
+ p.updateStatus(Status(buf))
+ return p.LastStatus, nil
+ }
+ if time.Now().Sub(start) > timeout {
+ return nil, errTimeout
+ }
+ }
+}
+
+// Request new status information from the printer. The printer
+// must be in an appropriate mode, i.e. on-line and not currently printing.
+func (p *Printer) UpdateStatus() error {
+ // Request status information.
+ if _, err := p.File.WriteString("\x1b\x69\x53"); err != nil {
+ return err
+ }
+
+ // Retrieve status information.
+ if _, err := p.pollStatusBytes(time.Second); err != nil {
+ p.LastStatus = nil
+ return err
+ }
+ return nil
+}
+
+var errErrorOccurred = errors.New("error occurred")
+var errUnexpectedStatus = errors.New("unexpected status")
+var errUnknownMedia = errors.New("unknown media")
+
+func (p *Printer) Print(image image.Image) error {
+ data := makePrintData(p.LastStatus, image)
+ if data == nil {
+ return errUnknownMedia
+ }
+ if _, err := p.File.Write(data); err != nil {
+ return err
+ }
+
+ // See diagrams: we may receive an error status instead of the transition
+ // to the printing state. Or even after it.
+ //
+ // Not sure how exactly cooling behaves and I don't want to test it.
+ for {
+ status, err := p.pollStatusBytes(10 * time.Second)
+ if err != nil {
+ return err
+ }
+
+ switch status.Type() {
+ case StatusTypePhaseChange:
+ // Nothing to do.
+ case StatusTypePrintingCompleted:
+ return nil
+ case StatusTypeErrorOccurred:
+ return errErrorOccurred
+ default:
+ return errUnexpectedStatus
+ }
+ }
+}
+
+// Close closes the underlying file.
+func (p *Printer) Close() error {
+ return p.File.Close()
+}
diff --git a/ql/status.go b/ql/status.go
new file mode 100644
index 0000000..ab3e675
--- /dev/null
+++ b/ql/status.go
@@ -0,0 +1,206 @@
+package ql
+
+import (
+ "fmt"
+ "io"
+ "strings"
+)
+
+// Status is a decoder for the status packed returned by the printer.
+type Status [32]byte
+
+func (s *Status) MediaWidthMM() int { return int(s[10]) }
+func (s *Status) MediaLengthMM() int { return int(s[17]) }
+
+type StatusType byte
+
+const (
+ StatusTypeReplyToRequest StatusType = 0x00
+ StatusTypePrintingCompleted = 0x01
+ StatusTypeErrorOccurred = 0x02
+ StatusTypeTurnedOff = 0x04
+ StatusTypeNotification = 0x05
+ StatusTypePhaseChange = 0x06
+)
+
+func (s *Status) Type() StatusType { return StatusType(s[18]) }
+
+type StatusPhase byte
+
+const (
+ StatusPhaseReceiving StatusPhase = 0x00
+ StatusPhasePrinting = 0x01
+)
+
+func (s *Status) Phase() StatusPhase { return StatusPhase(s[19]) }
+
+func decodeBitfieldErrors(b byte, errors [8]string) []string {
+ var result []string
+ for i := uint(0); i < 8; i++ {
+ if b&(1<