Linux下hp打印机驱动hplip分析-阿里云开发者社区

Hplip分析

版本号是2.14,源代码位置:http://hplipopensource.com。

图的来源：http://hplipopensource.com/node/128。

实践中使用的打印机型号:Deskjet 1010.分析的目的就是搞清楚一个灰色地带---打印机通信.

1.D-Bus初始化流程

D-Bus的初始化相同是在ui4/devmgr5.py開始的。

ui4/devmgr5.py

01 class DevMgr5(QMainWindow, Ui_MainWindow):

02 ......

03 # TODO: Make sbus init mandatory success, else exit

04 def initDBus(self):

05 self.dbus_loop = DBusQtMainLoop(set_as_default=True)

06 self.dbus_avail, self.service, self.session_bus = device.init_dbus(self.dbus_loop)

07 ......

08 # Receive events from the session bus

09 self.session_bus.add_signal_receiver(self.handleSessionSignal, sender_keyword='sender',

10 destination_keyword='dest', interface_keyword='interface',

11 member_keyword='member', path_keyword='path')

12 ......

这里调用了base/device.py中的init_dbus()。从第9行能够看出handleSessionSignal是D-Busserver端回调函数。

base/device.py

01 #

02 # DBus Support

03 #

05 def init_dbus(dbus_loop=None):

06 ......

07 try:

08 if dbus_loop is None:

09 session_bus = dbus.SessionBus()

10 else:

11 session_bus = dbus.SessionBus(dbus_loop)

12 ......

13 try:

14 log.debug("Connecting to com.hplip.StatusService (try #1)...")

15 service = session_bus.get_object('com.hplip.StatusService', "/com/hplip/StatusService")

16 dbus_avail = True

17 except dbus.exceptions.DBusException, e:

18 try:

19 os.waitpid(-1, os.WNOHANG)

20 except OSError:

21 pass

23 path = utils.which('hp-systray')

24 ......

25 log.debug("Running hp-systray: %s --force-startup" % path)

27 os.spawnlp(os.P_NOWAIT, path, 'hp-systray', '--force-startup')

29 log.debug("Waiting for hp-systray to start...")

30 time.sleep(1)

32 t = 2

33 while True:

34 try:

35 log.debug("Connecting to com.hplip.StatusService (try #%d)..." % t)

36 service = session_bus.get_object('com.hplip.StatusService', "/com/hplip/StatusService")

37 ......

39 return dbus_avail, service, session_bus

41 ......

第27行启动了hp-systray作为d-bus的server端。D-busserver端启动完成。

2.D-busserverhp-systray端启动

启动命令例如以下：

$ hp-systray --force-startup -g

说明:-g是调试模式启动

if __name__ == '__main__':
    ......
    if child_pid1:
        # parent (UI)
        os.close(w1)
        ......                
        else: # qt4
            try:
                import ui4.systemtray as systray
            except ImportError:
                log.error("Unable to load Qt4 support. Is it installed?

") mod.unlockInstance() sys.exit(1) try: systray.run(r1) finally: mod.unlockInstance() else: # child (dbus & device i/o [qt4] or dbus [qt3]) os.close(r1) if ui_toolkit == 'qt4': r2, w2 = os.pipe() r3, w3 = os.pipe() child_pid2 = os.fork() if child_pid2: # parent (dbus) os.close(r2) import hpssd hpssd.run(w1, w2, r3) else: # child (device i/o) os.close(w2) import hpdio hpdio.run(r2, w3) ......

启动了hpssd和hpdio。hpssd前者会从w3管道从读取hpdio写入的打印机状态信息。

以下单说hpdio怎样获取打印机状态当hpdio run起来的时候会做以下调用run(hpdio.py)->queryDevice(device.py)->status.StatusType10(status.py)->StatusType10Status(status.py)来获取打印机状态。

在queryDevice这个函数中出现了6种与打印机通信方式,各自是:

Type 1/2 (s: or VSTATUS:) status
Type 3/9 LaserJet PML
Type 6: LJ XML
Type 8: LJ PJL
Type 10: LEDM
Type 11: LEDM_FF_CC_0

而我眼下分析的这款打印机使用是第5种Type 10: LEDM通信协议 HPMUD_S_EWS_LEDM_CHANNEL。每种通信通信都有关于打印机状态值的定义,另外从这款打印机的DeviceId能够看出应该同一时候也是支持PJL的,这里先仅仅说第5种LEDM通信方式.LEDM的大体通信方式是基于HTTP,通信USB传输一个HTTP的GET指令,然后再通过USB读取打印机返回的HTTP超文本,一个是XML.

StatusType10Status调用流程：

StatusType10FetchUrl 从打印机获取状态数据
# Parse the product status XML 解析xml，提取状态值

StatusType10FetchUrl调用流程：

getUrl_LEDM
LocalOpenerEWS_LEDM().openhp()

openhp调用流程：（进入LEDM处理流程）

writeEWS_LEDM
readEWS_LEDM
readLEDMData

3.刷新状态的流程

toolbox.py

01 else: # qt4

02 ......

03 from ui4.devmgr5 import DevMgr5

04 ......

第三行能够看出启动了ui4文件夹下的devmgr5这个python。

ui4/devmgr5.py

01 class DevMgr5(QMainWindow, Ui_MainWindow):

02 ......

03 def initUI(self):

04 ......

05 self.DeviceRefreshAction.setIcon(QIcon(load_pixmap("refresh1", "16x16")))

06 self.connect(self.DeviceRefreshAction, SIGNAL("triggered()"), self.DeviceRefreshAction_activated)

07 ......

08 def DeviceRefreshAction_activated(self):

09 self.DeviceRefreshAction.setEnabled(False)

10 self.requestDeviceUpdate()

11 self.DeviceRefreshAction.setEnabled(True)

12 ......

13 def requestDeviceUpdate(self, dev=None, item=None):

14 """ Submit device update request to update thread. """

16 if dev is None:

17 dev = self.cur_device

19 if dev is not None:

20 dev.error_state = ERROR_STATE_REFRESHING

21 self.updateDevice(dev, update_tab=False)

23 self.sendMessage(dev.device_uri, '', EVENT_DEVICE_UPDATE_REQUESTED)

24 ......

25 def sendMessage(self, device_uri, printer_name, event_code, username=prop.username,

26 job_id=0, title=''):

28 device.Event(device_uri, printer_name, event_code, username,

29 job_id, title).send_via_dbus(self.session_bus)

30 .....

从第06行能够看出DeviceRefreshAction的槽是DeviceRefreshAction_activated在行8行，接着调用了requestDeviceUpdate。然后调用了sendMessage。然后调用了device.Event。这个在device.py中。在

base/device.py

01 class Event(object):

02 ......

03 def send_via_dbus(self, session_bus, interface='com.hplip.StatusService'):

04 if session_bus is not None and dbus_avail:

05 log.debug("Sending event %d to %s (via dbus)..." % (self.event_code, interface))

06 msg = lowlevel.SignalMessage('/', interface, 'Event')

07 msg.append(signature=self.dbus_fmt, *self.as_tuple())

08 session_bus.send_message(msg)

09 ......

这里调用的send_message是获取的d-bus实例的send_message,它在hpdio.py中。

hpdio.py

01 def send_message(device_uri, event_code, bytes_written=0):

02 args = [device_uri, '', event_code, prop.username, 0, '', '', bytes_written]

03 msg = lowlevel.SignalMessage('/', 'com.hplip.StatusService', 'Event')

04 msg.append(signature='ssisissi', *args)

05 SessionBus().send_message(msg)

这里是标准的d-bus通信。D-bus在收到这个消息后，会怎么处理，且看以后分析。以上是向server端请求事件。server端收到事件后会调用handleSessionSignal回调。

handleSessionSignal -> handleStatusReply -> updateDevice。

4.client与server端交互

clienthp-toolbox,server端hp-systray.他们分别启动后,怎样进行交互是一个重点,基于server端是有自己的消息通知和界面显示的,只是仅仅是一般的事件信息。

hp-toolbox能够主动获取打印机信息。

server端会主动向打印机设备获取状态信息，client获取的要是server保存好的状态信息。这个基本属于生产者-消费者之间的关系。

5.LEDM通信协议

全称： Low End Data Model（在hplib的status.py中有介绍：def StatusType10(func): # Low End Data Model）。

眼下已经是HP一个专利：专利EP2556480A1.

打开channel调用流程：

openEWS_LEDM -> __openChannel -> hpmudext.open_channel -> hpmud处理

读数据流程：

readEWS_LEDM -> __readChannel -> hpmudext.read_channel -> hpmud处理

写命令流程：

writeEWS_LEDM -> __writeChannel -> hpmudext.write_channel -> hpmud处理

以获取ProductStatusDyn记录一下收发数据的情况。

发送命令（报文）：

GET /DevMgmt/ProductStatusDyn.xml HTTP/1.1#015#012Accept: text/plain#015#012Host:localhost#015#012User-Agent:hplip#015#012#015#012

接收数据：

<?xml version="1.0" encoding="UTF-8"?>
<!-- THIS DATA SUBJECT TO DISCLAIMER(S) INCLUDED WITH THE PRODUCT OF ORIGIN. -->
<psdyn:ProductStatusDyn xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:dd="http://www.hp.com/schemas/imaging/con/dictionaries/1.0/" xmlns:ad="http://www.hp.com/schemas/imaging/con/ledm/alertdetails/2007/10/31" xmlns:pscat="http://www.hp.com/schemas/imaging/con/ledm/productstatuscategories/2007/10/31" xmlns:locid="http://www.hp.com/schemas/imaging/con/ledm/localizationids/2007/10/31" xmlns:psdyn="http://www.hp.com/schemas/imaging/con/ledm/productstatusdyn/2007/10/31" xsi:schemaLocation="http://www.hp.com/schemas/imaging/con/dictionaries/1.0/ ../schemas/dd/DataDictionaryMasterLEDM.xsd http://www.hp.com/schemas/imaging/con/ledm/alertdetails/2007/10/31 ../schemas/AlertDetails.xsd http://www.hp.com/schemas/imaging/con/ledm/productstatuscategories/2007/10/31 ../schemas/ProductStatusCategories.xsd http://www.hp.com/schemas/imaging/con/ledm/localizationids/2007/10/31 ../schemas/LocalizationIds.xsd http://www.hp.com/schemas/imaging/con/ledm/productstatusdyn/2007/10/31 ../schemas/ProductStatusDyn.xsd">
	<dd:Version>
		<dd:Revision>SVN-IPG-LEDM.216</dd:Revision>
		<dd:Date>2011-02-08</dd:Date>
	</dd:Version>
	<psdyn:Status>
		<pscat:StatusCategory>closeDoorOrCover</pscat:StatusCategory>
		<locid:StringId>65568</locid:StringId>
	</psdyn:Status>
	<psdyn:AlertTable>
		<dd:ModificationNumber>6</dd:ModificationNumber>
		<psdyn:Alert>
			<ad:ProductStatusAlertID>closeDoorOrCover</ad:ProductStatusAlertID>
			<locid:StringId>65568</locid:StringId>
			<dd:SequenceNumber>5</dd:SequenceNumber>
			<ad:Severity>Error</ad:Severity>
			<ad:AlertPriority>1</ad:AlertPriority>
			<ad:AlertDetails>
				<ad:AlertDetailsDoorCoverLocation>cover</ad:AlertDetailsDoorCoverLocation>
			</ad:AlertDetails>
			<dd:ResourceURI>/DevMgmt/ProductConfigDyn.xml</dd:ResourceURI>
			<dd:ResourceType>ledm:hpLedmProductConfigDyn</dd:ResourceType>
		</psdyn:Alert>
		<psdyn:Alert>
			<ad:ProductStatusAlertID>cartridgeMissing</ad:ProductStatusAlertID>
			<locid:StringId>65537</locid:StringId>
			<dd:SequenceNumber>4</dd:SequenceNumber>
			<ad:Severity>Error</ad:Severity>
			<ad:AlertPriority>11</ad:AlertPriority>
			<ad:AlertDetails>
				<ad:AlertDetailsMarkerColor>Black</ad:AlertDetailsMarkerColor>
				<ad:AlertDetailsConsumableTypeEnum>inkCartridge</ad:AlertDetailsConsumableTypeEnum>
				<ad:AlertDetailsMarkerLocation>1</ad:AlertDetailsMarkerLocation>
			</ad:AlertDetails>
			<dd:ResourceURI>/DevMgmt/ConsumableConfigDyn.xml</dd:ResourceURI>
			<dd:ResourceType>ledm:hpLedmConsumableConfigDyn</dd:ResourceType>
		</psdyn:Alert>
		<psdyn:Alert>
			<ad:ProductStatusAlertID>cartridgeMissing</ad:ProductStatusAlertID>
			<locid:StringId>65537</locid:StringId>
			<dd:SequenceNumber>3</dd:SequenceNumber>
			<ad:Severity>Error</ad:Severity>
			<ad:AlertPriority>11</ad:AlertPriority>
			<ad:AlertDetails>
				<ad:AlertDetailsMarkerColor>CyanMagentaYellow</ad:AlertDetailsMarkerColor>
				<ad:AlertDetailsConsumableTypeEnum>inkCartridge</ad:AlertDetailsConsumableTypeEnum>
				<ad:AlertDetailsMarkerLocation>0</ad:AlertDetailsMarkerLocation>
			</ad:AlertDetails>
			<dd:ResourceURI>/DevMgmt/ConsumableConfigDyn.xml</dd:ResourceURI>
			<dd:ResourceType>ledm:hpLedmConsumableConfigDyn</dd:ResourceType>
		</psdyn:Alert>
	</psdyn:AlertTable>
</psdyn:ProductStatusDyn>

pscat:StatusCategory字段记录的正是打印机的当前状态。

6.hpmud分析

MUlti-point transport Driver or HPMUD represents the I/O layer for HPLIP. HPMUD does not depend on Linux specific libusb extensions. This means any UNIX/Linux derivative that supports libusb may work with HPLIP. A public HPLIP "C" API is exposed through hpmud. See hpmud.h for documentation. A python wrapper for hpmud, called hpmudext, is also available.

以上是官网介绍，如开头图中所看到的，hpmud是负责真正和打印机设备进行通信的，它基于libusb开发，所以能够执行于所以含libusb的系统中。

hpmud相同实现了多种通信方式：

musb 基于眼下经常使用的libusb通信.（本次採用打印机正是用这样的方式）
musb_libusb01 基于眼下较老版本号的libusb通信.
jd 基于jetdirect 的打印机通信.
pml 和python层相应。是一种打印语言
pp Parallel port 并口通信方式

这里仅仅说musb通信方式。因为基于libusb，所以这里的musb就类似于java和c中的jni仅仅是一个接口的转接，musb会把python传送过来的指令通过libusb直接丢给打印机设备。

另符上hpmud的调试方法，调试宏DBG的实现是syslog，把这个宏打开会将log信息输出到/var/log/syslog中。

7.C语言实现状态获取

经过20多天的，无情的看源代码，最终有所获。最终把Device.py中获取状态的部分用C语言实现了。提取了关键部分。如今能够正常获取打印机状态。因为之前没有接触过HTTP协议，一个错误的报文格式使得我连续非常多天都处于迷茫之中，如今看来在于心智还是不全然成熟。在感觉要成功的时候就静不下心来了，不在阅读最后一段代码，然后有时那段代码才是最重要的。"Door Open"从打印机到PC屏幕的流程最终走通了。

#include <stdio.h>
#include <string.h>
#include <hpmud.h>
#include <malloc.h>

#ifdef  DEBUG
#define debug(fmt,args...)  debug (fmt ,##args)
#define debugX(level,fmt,args...) if (DEBUG>=level) debug(fmt,##args);
#else
#define debug(fmt,args...)
#define debugX(level,fmt,args...)
#endif  /* DEBUG */

static HPMUD_DEVICE dd;
static HPMUD_CHANNEL cd;

#define MALLOC(type, n)  (type*)malloc(n*sizeof(type))

static int __readChannel(int bytes_to_read, int* reply, int allow_short_read, int timeout)
{
    bytes_to_read = 1024;
    char data[1024] = {0};
    int ret = 0;
    int num_bytes = 0;
    int len = 0;
    int *p = reply;
    while (1)
    {
        ret = hpmud_read_channel(dd, cd, data, 1024, timeout, &num_bytes);
        debug("Result code=%d\n", ret);
        len = strlen(data);
        if(ret == HPMUD_R_IO_TIMEOUT)
        {
            debug("I/O timeout\n");
            break;
        }
        if(ret != HPMUD_R_OK)
        {
            debug("Channel read error\n");
            break;
        }

        //debug("read_buf:%s\n", data);

        if(!len)
        {
            debug("End of data\n");
            break;
        }

        memcpy(p, data, len);

        if (num_bytes == bytes_to_read)
        {
            debug("Full read complete.\n");
            break;
        }

        if (allow_short_read && (num_bytes < bytes_to_read))
        {
            debug("Allowed short read of %d of %d bytes complete.\n", num_bytes, bytes_to_read);
            break;
        }
    }

    debug("Saved %d total bytes to stream.\n", num_bytes);
    return num_bytes;
}

void readLEDMData()
{
    int timeout = 6;
    const char* END_OF_DATA="0\r\n\r\n";
    int bytes_read = 0;
    int bytes_requested = 1024;
    char temp_buf[1024] = {0};  //大小要一致
    int chunkedFlag = 1;
    char* result = NULL;
    char *reply = (int*)MALLOC(unsigned char, 5*1024);
    char *offset = reply;
    if(reply == NULL)
    {
        fprintf(stderr, "MALLC FAILURE!\n");
        return;
    }

    bytes_read = __readChannel(bytes_requested, reply, 1, timeout);
    offset += bytes_read;
    //debug("%s:%s\n", __func__, reply);

    // 默认chunked分块.
    chunkedFlag = 1;

    //result = strtok(reply, "\n");

    //debug("result=%s\n", result);

    while (bytes_read > 0)
    {
        bytes_read = __readChannel(bytes_requested, (int*)temp_buf, 1, timeout);

        //reply.write(temp_buf.getvalue());
        memcpy(offset, temp_buf, bytes_read);
        debug("%s:%s\n", __func__, offset);
        offset += bytes_read;

        if(!chunkedFlag) // Unchunked data
        {
            // do nothing!
        }
        else // Chunked data end
        {
            //END_OF_DATA == temp_buf.getvalue();
            if(!strncmp(temp_buf, END_OF_DATA, sizeof(END_OF_DATA)))
                break;
        }
    }

    printf("%s:%s\n", __func__, reply);

    free(reply);
    reply = NULL;
}

int main(void)
{
    enum HPMUD_RESULT res;
    const char *device_uri = "hp:/usb/Deskjet_1010_series?serial=CN39I18M1805S8";
    enum HPMUD_IO_MODE io_mode = HPMUD_RAW_MODE;

    // 打开设备获得
    res = hpmud_open_device(device_uri, io_mode, &dd);
    if (res != HPMUD_R_OK)
    {
        fprintf(stderr, "error opening device (code=%d)\n", res);
        return 1;
    }

    // 打开频道获得频道id
    res = hpmud_open_channel(dd, HPMUD_S_EWS_LEDM_CHANNEL, &cd);
    if (res != HPMUD_R_OK)
    {
        fprintf(stderr, "error opening channel (code=%d)\n", res);
        return 1;
    }

    char buf[1024] = "GET /DevMgmt/ProductStatusDyn.xml HTTP/1.1\r\nAccept: text/plain\r\nHost:localhost\r\nUser-Agent:hplip\r\n\r\n";
    //char ConsumableConfigDyn[] = "GET /DevMgmt/ConsumableConfigDyn.xml HTTP/1.1#015#012Accept: text/plain#015#012Host:localhost#015#012User-Agent:hplip#015#012#015#012";
    int bit = 0;

    // 写入命令
    res = hpmud_write_channel(dd, cd, buf, 100, 6, &bit);
    if (res != HPMUD_R_OK)
    {
        fprintf(stderr, "error hpmud_write_channel (code=%d)\n", res);
        return 1;
    }

    readLEDMData();
    return 0;

    hpmud_close_channel(dd, cd);
    hpmud_close_device(dd);

    return 0;
}

本程序会从打印出所得到状态的数据，pscat:StatusCategory字段中的就是状态值了，事实上能到了如《关于打印机状态的获取》提到15个左右的状态，可是这个协议所规定的状态所有罗列出来：

字串	状态	编号
processing	STATUS_PRINTER_PRINTING	1002
ready	STATUS_PRINTER_IDLE	1000
closeDoorOrCover	STATUS_PRINTER_DOOR_OPEN	1802
shuttingDown	STATUS_PRINTER_TURNING_OFF	1003
cancelJob	STATUS_PRINTER_CANCELING	1005
trayEmptyOrOpen	STATUS_PRINTER_OUT_OF_PAPER	1009
jamInPrinter	STATUS_PRINTER_MEDIA_JAM	1014
hardError	STATUS_PRINTER_HARD_ERROR	1018
outputBinFull	STATUS_PRINTER_OUTPUT_BIN_FULL	1002
unexpectedSizeInTray sizeMismatchInTray	STATUS_PRINTER_MEDIA_SIZE_MISMATCH	1023
insertOrCloseTray2	STATUS_PRINTER_TRAY_2_MISSING	1029
scannerError	EVENT_SCANNER_FAIL	2002
scanProcessing	EVENT_START_SCAN_JOB	2000
scannerAdfLoaded	EVENT_SCAN_ADF_LOADED	2004
scanToDestinationNotSet	EVENT_SCAN_TO_DESTINATION_NOTSET	2005
scanWaitingForPC	EVENT_SCAN_WAITING_FOR_PC	2006
scannerAdfJam	EVENT_SCAN_ADF_JAM	2007
scannerAdfDoorOpen	EVENT_SCAN_ADF_DOOR_OPEN	2008
faxProcessing	EVENT_START_FAX_JOB	3000
faxSending	STATUS_FAX_TX_ACTIVE	3004
faxReceiving	STATUS_FAX_RX_ACTIVE	3005
faxDialing	EVENT_FAX_DIALING	3006
faxConnecting	EVENT_FAX_CONNECTING	3007
faxSendError	EVENT_FAX_SEND_ERROR	3008
faxErrorStorageFull	EVENT_FAX_ERROR_STORAGE_FULL	3009
faxReceiveError	EVENT_FAX_RECV_ERROR	3010
faxBlocking	EVENT_FAX_BLOCKING	3011
inPowerSave	STATUS_PRINTER_POWER_SAVE	1046
incorrectCartridge	STATUS_PRINTER_CARTRIDGE_WRONG	1047
cartridgeMissing	STATUS_PRINTER_CARTRIDGE_MISSING	1048
missingPrintHead	STATUS_PRINTER_PRINTHEAD_MISSING	1049
scannerADFMispick	STATUS_SCANNER_ADF_MISPICK	1050
mediaTooShortToAutoDuplex	STATUS_PRINTER_PAPER_TOO_SHORT_TO_AUTODUPLEX	1051
insertOrCloseTray	STATUS_PRINTER_TRAY_2_3_DOOR_OPEN	1052
inkTooLowToPrime	STATUS_PRINTER_INK_TOO_LOW_TO_PRIME	1053
cartridgeVeryLow	STATUS_PRINTER_VERY_LOW_ON_INK	1054
wasteMarkerCollectorAlmostFull	STATUS_PRINTER_SERVICE_INK_CONTAINER_ALMOST_FULL	1055
wasteMarkerCollectorFull	STATUS_PRINTER_SERVICE_INK_CONTAINER_FULL	1056
wasteMarkerCollectorFullPrompt	STATUS_PRINTER_SERVICE_INK_CONTAINER_FULL_PROMPT	1057
missingDuplexer	STATUS_PRINTER_DUPLEX_MODULE_MISSING	1058
printBarStall	STATUS_PRINTER_PRINTHEAD_JAM	1059
outputBinClosed	STATUS_PRINTER_CLEAR_OUTPUT_AREA	1060
outputBinOpened	STATUS_PRINTER_CLEAR_OUTPUT_AREA	1060
reseatDuplexer	STATUS_PRINTER_RESEAT_DUPLEXER	1061
unexpectedTypeInTray	STATUS_PRINTER_MEDIA_TYPE_MISMATCH	1042
manuallyFeed	STATUS_MANUALLY_FEED	1062
	STATUS_UNKNOWN_CODE	1065

扩展：眼下仅仅是上一个课题的总结。这之后的应用还有不少的问题，怎样应用。以及和利用设备节点打印是否冲突，以及是否能打印也基于hpmud。

。。

8.意外收获

老天真的会眷恋努力的人，刚在PC上实现基于HPMUD的状态获取，考虑着进行三步走中的更为繁琐的后两步(移植到嵌入式Linux+移植到Android)的时候，上天又送我一份大礼－－打印机状态获取的还有一种方式：通过DeviceId。

这个可能不一定适合全部打印机。可是能够确定的是全然适应我如今正在调试的这款。

关于DeviceId从一開始看打印机相关的东西的时候最先接触到的就是这个DeviceId,能够说我对它的感情也是跌宕起伏。从一喜得DeviceId。到认为其作用单一。到如今的强大无比。

以下说点正经的，在《互联网打印协议-rfc2911》的printer-state-reasons章节规定了打印机异常状态码。也就是说除了使用HP自己定义的LEDM获取的状态外，相同还能够通过标准的IPP协议得到状态值。由此也能延伸出一个问题，CUPS应该也能够获取打印机状态了。可是却没有做不论什么显示。至于是为什么。这个还是比較玄乎。

详细来看DeviceID中含有状态的“S”字段:S:038000C484a01021002c1f01100c2881100;首先说明的是这个当中的都是16进制的数。前两位是版本号信息，依据版本号信息不同。状态码所在的位置也不同，比方这里的版本号号为03，那么状态码在第16位的两位数这里为00转换为10进制也是0。这个状态代表空暇。有时候代码比语言更有说服力。

java版本号:

　　    public int getPrinterStatusCode() {
　　        String deviceId = getPrinterDeivceId();
　　        int ippStatus = -1;
　　        int pSf = 2;
　　
　　        if(deviceId == null)
　　            return ippStatus;
　　        
　　        // somthing
　　        String str[] = deviceId.split(";S:");
　　        if(str.length > 1)
　　        {
　　            if(str[1] != null)
　　            {
　　                int ver=Integer.parseInt(str[1].substring(0,2), 16);
　　                       /* Position pointer to printer state subfield. */
　　                switch (ver)
　　                {
　　                  case 0:
　　                  case 1:
　　                  case 2:
　　                     pSf+=12;
　　                     break;
　　                  case 3:
　　                     pSf+=14;
　　                     break;
　　                  case 4:
　　                     pSf+=18;
　　                     break;
　　                  default:
　　                     Slog.w(LOG_TAG, "WARNING: unknown S-field version=" + ver + "\n");
　　                     pSf+=12;
　　                     break;
　　                }
　　                ippStatus = Integer.parseInt(str[1].substring(pSf, pSf + 2), 16);
　　            }
　　        }
　　        return ippStatus;
　　    }

C版本号：

static int get_printer_status_code(const char* device_id)
{
	const char* id = device_id;
    char *pSf;
    int ver;
    int status = 0;

    /* Check for valid S-field in device id string. */
    if ((pSf = strstr(id, ";S:")) == NULL)
    {
    	/* No S-field, use status register instead of device id. */
    	/* do nothing */
    	goto bugout;
    }
    else
    {
       /* Valid S-field, get version number. */
       pSf+=3;
       ver = 0;
       HEX2INT(*pSf, ver);
       pSf++;
       ver = ver << 4;
       HEX2INT(*pSf, ver);
       pSf++;

       /* Position pointer to printer state subfield. */
       switch (ver)
       {
          case 0:
          case 1:
          case 2:
             pSf+=12;
             break;
          case 3:
             pSf+=14;
             break;
          case 4:
             pSf+=18;
             break;
          default:
             printf("WARNING: unknown S-field version=%d\n", ver);
             pSf+=12;
             break;
       }

       /* Extract VStatus.*/
       status = 0;
       HEX2INT(*pSf, status);
       pSf++;
       status = status << 4;
       HEX2INT(*pSf, status);
    }
    printf("status:%d\n", status);

bugout:
    return status;
}

状态码相应关系：

   VSTATUS_IDLE = 0,
   VSTATUS_BUSY = 1,
   VSTATUS_PRNT = 2,      /* io printing */
   VSTATUS_OFFF = 3,      /* turning off */
   VSTATUS_RPRT = 4,      /* report printing */
   VSTATUS_CNCL = 5,      /* canceling */
   VSTATUS_IOST = 6,      /* io stall */
   VSTATUS_DRYW = 7,      /* dry time wait */
   VSTATUS_PENC = 8,      /* pen change */
   VSTATUS_OOPA = 9,      /* out of paper */
   VSTATUS_BNEJ = 10,      /* banner eject needed */
   VSTATUS_BNMZ = 11,      /* banner mismatch */
   VSTATUS_PHMZ = 12,      /* photo mismatch */
   VSTATUS_DPMZ = 13,      /* duplex mismatch */
   VSTATUS_PAJM = 14,      /* media jam */
   VSTATUS_CARS = 15,      /* carriage stall */
   VSTATUS_PAPS = 16,      /* paper stall */
   VSTATUS_PENF = 17,      /* pen failure */
   VSTATUS_ERRO = 18,      /* hard error */
   VSTATUS_PWDN = 19,      /* power down */
   VSTATUS_FPTS = 20,      /* front panel test */
   VSTATUS_CLNO = 21       /* clean out tray missing */

文章至此该结束了。

其他：

Linux打印驱动知识点

1.关于DeviceId各段意义见《ieee_1284》

2.关于LEDM见《DISCOVERING PC-CONNECTED DEVICES》

3.Syslog见《syslog-example》经过实践输出到了/var/log/syslog.

4.关于Eclipse CD高版本号的Memory View不能显示相应的Text.换成Helios Service Release 2使用New Rendrings->Traditional.

5.关于PJL(打印机控制语言)《Printer Job Language Technical Reference Manual》

6.终于选择了基于deviceId的方法来实现。所以临时不再用hpmud的方法了。可是已经代码已经实现了printDate和基于ledm获取打印机的状态信息。

#include <stdio.h>
#include <string.h>
#include <hpmud.h>
#include <malloc.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <pthread.h>
#include <stdlib.h>
#include <stdarg.h>


//#define DEBUG

#ifdef  DEBUG
#define debug(fmt,args...)  printf (fmt ,##args)
#define debugX(level,fmt,args...) if (DEBUG>=level) debug(fmt,##args);
#else
#define debug(fmt,args...)
#define debugX(level,fmt,args...)
#endif  /* DEBUG */

// hp printer device
static HPMUD_DEVICE hd;

#define MALLOC(type, n)  (type*)malloc(n*sizeof(type))

// HPMUD_I_MAX
#define HPMUD_I_MAX  18
static int channels[HPMUD_I_MAX] = {0};

typedef HPMUD_CHANNEL(open_channel)(void);
typedef int(read_func)(int bytes_requested, char* reply, int timeout);

enum BACKEND_RESULT
{
  BACKEND_OK = 0,
  BACKEND_FAILED = 1,           /* use error-policy */
  BACKEND_HOLD = 3,             /* hold job */
  BACKEND_STOP = 4,             /* stop queue */
  BACKEND_CANCEL = 5            /* cancel job */
};

struct pjl_attributes
{
   int pjl_device;   /* 0=disabled, 1=enabled */
   int current_status;
   int eoj_pages;        /* end-of-job pages */
   int abort;         /* 0=no, 1=yes */
   int done;          /* 0=no, 1=yes */
   HPMUD_DEVICE dd;
   HPMUD_CHANNEL cd;
   pthread_t tid;
   pthread_mutex_t mutex;
   pthread_cond_t done_cond;
};

#define _STRINGIZE(x) #x
#define STRINGIZE(x) _STRINGIZE(x)

#define BUG(args...) bug(__FILE__ " " STRINGIZE(__LINE__) ": " args)

#ifdef HP_DEBUG
   #define DBG(args...) syslog(LOG_INFO, __FILE__ " " STRINGIZE(__LINE__) ": " args)
   #define DBG_DUMP(data, size) sysdump((data), (size))
   #define DBG_SZ(args...) syslog(LOG_INFO, args)
#else
   #define DBG(args...)
   #define DBG_DUMP(data, size)
   #define DBG_SZ(args...)
#endif

#define RETRY_TIMEOUT 30  /* seconds */
#define EXCEPTION_TIMEOUT 45 /* seconds */

#define NFAULT_BIT  0x08
#define PERROR_BIT  0x20

#define OOP             (NFAULT_BIT | PERROR_BIT)
#define JAMMED          (PERROR_BIT)
#define ERROR_TRAP      (0)

#define STATUS_MASK (NFAULT_BIT | PERROR_BIT)

#define DEVICE_IS_OOP(reg)  ((reg & STATUS_MASK) == OOP)
#define DEVICE_PAPER_JAMMED(reg)  ((reg & STATUS_MASK) == JAMMED)
#define DEVICE_IO_TRAP(reg)       ((reg & STATUS_MASK) == ERROR_TRAP)

#define HEX2INT(x, i) if (x >= '0' && x <= '9')      i |= x - '0'; \
                       else if (x >= 'A' && x <= 'F') i |= 0xA + x - 'A'; \
                       else if (x >= 'a' && x <= 'f') i |= 0xA + x - 'a'

/* Definitions for hpLogLevel in cupsd.conf. */
#define BASIC_LOG          1
#define SAVE_PCL_FILE      2
#define SAVE_INPUT_RASTERS 4
#define SEND_TO_PRINTER_ALSO    8

/* Actual vstatus codes are mapped to 1000+vstatus for DeviceError messages. */
typedef enum
{
   VSTATUS_IDLE = 1000,
   VSTATUS_BUSY,
   VSTATUS_PRNT,      /* io printing */
   VSTATUS_OFFF,      /* turning off */
   VSTATUS_RPRT,      /* report printing */
   VSTATUS_CNCL,      /* canceling */
   VSTATUS_IOST,      /* io stall */
   VSTATUS_DRYW,      /* dry time wait */
   VSTATUS_PENC,      /* pen change */
   VSTATUS_OOPA,      /* out of paper */
   VSTATUS_BNEJ,      /* banner eject needed */
   VSTATUS_BNMZ,      /* banner mismatch */
   VSTATUS_PHMZ,      /* photo mismatch */
   VSTATUS_DPMZ,      /* duplex mismatch */
   VSTATUS_PAJM,      /* media jam */
   VSTATUS_CARS,      /* carriage stall */
   VSTATUS_PAPS,      /* paper stall */
   VSTATUS_PENF,      /* pen failure */
   VSTATUS_ERRO,      /* hard error */
   VSTATUS_PWDN,      /* power down */
   VSTATUS_FPTS,      /* front panel test */
   VSTATUS_CLNO       /* clean out tray missing */
} VSTATUS;

#define EVENT_START_JOB 500
#define EVENT_END_JOB 501

//const char pjl_status_cmd[] = "\e%-12345X@PJL INFO STATUS \r\n\e%-12345X";
static const char pjl_ustatus_cmd[] = "\e%-12345X@PJL USTATUS DEVICE = ON \r\n@PJL USTATUS JOB = ON \r\n@PJL JOB \r\n\e%-12345X";
static const char pjl_job_end_cmd[] = "\e%-12345X@PJL EOJ \r\n\e%-12345X";
static const char pjl_ustatus_off_cmd[] = "\e%-12345X@PJL USTATUSOFF \r\n\e%-12345X";

static int bug(const char *fmt, ...)
{
   char buf[256];
   va_list args;
   int n;

   va_start(args, fmt);

   if ((n = vsnprintf(buf, 256, fmt, args)) == -1)
      buf[255] = 0;     /* output was truncated */

   fprintf(stderr, "%s", buf);
   //syslog(LOG_ERR, "%s", buf);

   fflush(stderr);
   va_end(args);
   return n;
}

/**
 * 因为使用的数组来实现python中的字典
 * 所以要将字符串转化为相应数字
 * openChannle和closeChannel中会用到
 */
static int get_service_name_num(char* service_name)
{
    int ser_name_id = 0;

    if(!strncmp(HPMUD_S_PRINT_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 1;
    else if(!strncmp(HPMUD_S_PML_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 2;
    else if(!strncmp(HPMUD_S_SCAN_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 3;
    else if(!strncmp(HPMUD_S_FAX_SEND_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 4;
    else if(!strncmp(HPMUD_S_CONFIG_UPLOAD_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 5;
    else if(!strncmp(HPMUD_S_CONFIG_DOWNLOAD_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 6;
    else if(!strncmp(HPMUD_S_MEMORY_CARD_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 7;
    else if(!strncmp(HPMUD_S_EWS_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 8;
    else if(!strncmp(HPMUD_S_EWS_LEDM_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 9;
    else if(!strncmp(HPMUD_S_SOAP_SCAN, service_name, strlen(service_name)))
        ser_name_id = 10;
    else if(!strncmp(HPMUD_S_SOAP_FAX, service_name, strlen(service_name)))
        ser_name_id = 11;
    else if(!strncmp(HPMUD_S_DEVMGMT_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 12;
    else if(!strncmp(HPMUD_S_MARVELL_SCAN_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 13;
    else if(!strncmp(HPMUD_S_MARVELL_FAX_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 14;
    else if(!strncmp(HPMUD_S_LEDM_SCAN, service_name, strlen(service_name)))
        ser_name_id = 15;
    else if(!strncmp(HPMUD_S_WIFI_CHANNEL, service_name, strlen(service_name)))
        ser_name_id = 16;
    else
        ser_name_id = 0;

    return ser_name_id;
}

static int __closeChannel(char* service_name)
{
    int result_code = 0;
    int ser_name_id = get_service_name_num(service_name);
    //if not self.mq['io-mode'] == IO_MODE_UNI and
    //  if self.io_state == IO_STATE_HP_OPEN:

//        service_name = service_name.upper();
    if(channels[ser_name_id] != 0)
    {
        printf("Closing %s channel...\n", service_name);
        result_code = hpmud_close_channel(hd, channels[ser_name_id]);
        if (result_code != HPMUD_R_OK)
        {
            fprintf(stderr, "error hpmud_close_channel (code=%d)\n", result_code);
            return 1;
        }
        else
        {
            channels[ser_name_id] = 0;
        }
    }

    return 0;
}

/*
 * open channel
 */
static int __openChannel(char* service_name)
{
    int result_code = 0;
    int channel_id  = 0;
    HPMUD_CHANNEL ret = 0;
    int ser_name_id = get_service_name_num(service_name);

    if (channels[ser_name_id] == 0)
    {
        printf("Opening %s channel...\n", service_name);

        result_code = hpmud_open_channel(hd, service_name, &channel_id);
        if (result_code != HPMUD_R_OK)
        {
            fprintf(stderr, "error opening channel (code=%d)\n", result_code);
            exit(1);
        }
        else
        {
            channels[ser_name_id] = channel_id;
            debug("channel-id=%d\n", channel_id);
            ret = channel_id;
        }
    }
    else
    {
        printf("already open!\n");
        ret = channels[ser_name_id];
    }
    return ret;
}

/*
 * read channel
 */
static int __readChannel(open_channel opener, int bytes_to_read, char* reply, int allow_short_read, int timeout)
{
    bytes_to_read = 1024;
    char data[1024] = {0};
    int ret = 0;
    int num_bytes = 0;
    int len = 0;
    char *p = reply;
    HPMUD_CHANNEL channel_id = opener();

    while (1)
    {
        ret = hpmud_read_channel(hd, channel_id, data, 1024, timeout, &num_bytes);
        debug("Result code=%d\n", ret);
        len = strlen(data);
        if(ret == HPMUD_R_IO_TIMEOUT)
        {
            debug("I/O timeout\n");
            break;
        }
        if(ret != HPMUD_R_OK)
        {
            debug("Channel read error\n");
            break;
        }

        //debug("read_buf:%s\n", data);

        if(!len)
        {
            debug("End of data\n");
            break;
        }

        memcpy(p, data, len);

        if (num_bytes == bytes_to_read)
        {
            debug("Full read complete.\n");
            break;
        }

        if (allow_short_read && (num_bytes < bytes_to_read))
        {
            debug("Allowed short read of %d of %d bytes complete.\n", num_bytes, bytes_to_read);
            break;
        }
    }

    debug("Saved %d total bytes to stream.\n", num_bytes);
    return num_bytes;
}

/**
 * write channel
 */
static int __writeChannel(open_channel opener, const char* data, int total_bytes_to_write)
{
    HPMUD_DEVICE  device_id  = hd;
    HPMUD_CHANNEL channel_id = opener();
    int          result_code = 0;
    int        bytes_written = 0;
    const char*             buffer = data;
    int            bytes_out = 0;
    int      max_message_len = 16384;
    int              timeout = 45;
    int       bytes_to_write = total_bytes_to_write;

    while(bytes_to_write > 0)
    {
        result_code = hpmud_write_channel(device_id, channel_id, buffer, bytes_to_write < max_message_len ? bytes_to_write : max_message_len, timeout, &bytes_written);

        printf("Result code=%d\n", result_code);
        if (result_code != HPMUD_R_OK)
        {
            fprintf(stderr, "Channel write error\n");
            return -1;
        }

        buffer += max_message_len;
        bytes_out += bytes_written;
        bytes_to_write -= bytes_written;
    }

    if (total_bytes_to_write != bytes_out)
    {
        printf("total_bytes_to_write =%d =\\= bytes_out=%d\n", total_bytes_to_write, bytes_out);
        return -1;
    }

    //printf("%s end\n", __func__);
    return bytes_out;
}

static HPMUD_CHANNEL openEWS_LEDM()
{
    return __openChannel(HPMUD_S_EWS_LEDM_CHANNEL);
}

static HPMUD_CHANNEL openPrint()
{
    return __openChannel(HPMUD_S_PRINT_CHANNEL);
}

static int closePrint(void)
{
    return __closeChannel(HPMUD_S_PRINT_CHANNEL);
}

static int closeEWS_LEDM(void)
{
    return __closeChannel(HPMUD_S_EWS_LEDM_CHANNEL);
}

static int readEWS_LEDM(int bytes_requested, char* reply, int timeout)
{
    open_channel* opener = openEWS_LEDM;
    return __readChannel(opener, bytes_requested, reply, 1, timeout);
}

static int writePrint(const char* data, int len)
{
    open_channel* opener = openPrint;
    int ret = EXIT_FAILURE;
    int result_code = 0;
    //TODO:delect hpmud_write_channel
    /* Enable unsolicited status. */
    //ret = hpmud_write_channel(hd, channel_id, pjl_ustatus_cmd, sizeof(pjl_ustatus_cmd)-1, 5, &bytes_written);

    result_code = __writeChannel(opener, data, len);
    if(result_code != len)
    {
    	printf("ret != len(%s:%u,%s)\n", __FILE__, __LINE__, __func__);
    	goto bugout;
    }
    /* Look for job end status. */

    //ret = hpmud_write_channel(hd, channel_id, pjl_ustatus_off_cmd, sizeof(pjl_ustatus_off_cmd)-1, 5, &bytes_written);
    result_code = __writeChannel(opener, pjl_job_end_cmd, sizeof(pjl_job_end_cmd)-1);
    if(result_code != (sizeof(pjl_job_end_cmd)-1))
    {
    	printf("ret != len(%s:%u,%s)\n", __FILE__, __LINE__, __func__);
    	goto bugout;
    }

    ret = EXIT_SUCCESS;
bugout:
    return ret;
}

static int writeEWS_LEDM(const char* data, int len)
{
    open_channel* opener = openEWS_LEDM;
    return __writeChannel(opener, data, len);
}


static void readLEDMData(read_func* func, char *reply)
{
    int timeout = 6;
    const char* END_OF_DATA="0\r\n\r\n";
    int bytes_read = 0;
    int bytes_requested = 1024;
    char temp_buf[1024] = {0};  //大小要一致
    int chunkedFlag = 1;
    char *offset = reply;
    if(reply == NULL)
    {
        fprintf(stderr, "MALLC FAILURE!\n");
        return;
    }

    bytes_read = func(bytes_requested, reply, timeout);
    offset += bytes_read;
    //debug("%s:%s\n", __func__, reply);

    // 默认chunked分块.
    chunkedFlag = 1;

    //result = strtok(reply, "\n");

    //debug("result=%s\n", result);

    while (bytes_read > 0)
    {
        bytes_read = readEWS_LEDM(bytes_requested, (char*)temp_buf, timeout);

        //reply.write(temp_buf.getvalue());
        memcpy(offset, temp_buf, bytes_read);
        debug("%s:%s\n", __func__, offset);
        offset += bytes_read;

        if(!chunkedFlag) // Unchunked data
        {
            // do nothing!
        }
        else // Chunked data end
        {
            //END_OF_DATA == temp_buf.getvalue();
            if(!strncmp(temp_buf, END_OF_DATA, sizeof(END_OF_DATA)))
                break;
        }
    }

    printf("%s:%s\n", __func__, reply);

}

static int open_hp(const char* url, char* reply)
{
    char data[512] = {0};
    debug("open_hp(%s)\n", url);

//    match_obj = http_pat_url.search(url)
//    loc = url.split("=")[url.count("=")]

    openEWS_LEDM();

    sprintf(data, "GET %s HTTP/1.1\r\nAccept: text/plain\r\nHost:localhost\r\nUser-Agent:hplip\r\n\r\n", url);
    writeEWS_LEDM(data, strlen(data));

    //while dev.readEWS_LEDM(512, reply, timeout=3):
        //pass

    read_func* func = readEWS_LEDM;

    readLEDMData(func, reply);

    //reply.seek(0);

    //return reply.getvalue();
    return 0;

}
void getEWSUrl_LEDM(const char* url, char* reply)
{
//    int self, url, stream, footer;
//    url2 = "%s&loc=%s" % (self.device_uri.replace('hpfax:', 'hp:'), url);
//    data = self;
//    opener = LocalOpenerEWS_LEDM({});
//    opener.open_hp(url2, data);
    open_hp(url, reply);
    closeEWS_LEDM();
}

void printData()
{
    char *buf = (char*)MALLOC(unsigned char, 107968);
    if(buf == NULL)
    {
        fprintf(stderr, "MALLC FAILURE!\n");
        return;
    }

    int fd = open("/home/kangear/bin.bin", O_RDONLY);
    if(fd == -1)
    {
        fprintf(stderr, "open file error!\n");
        return;
    }

    int num = read(fd, buf, 107968);
    if(num == -1)
    {
        fprintf(stderr, "read file error!\n");
        return;
    }

    writePrint(buf, num);

    close(fd);
    free(buf);
    buf = NULL;
}

/**
 * device discovery
 * if there is hp device return EXIT_SUCCESS, but EXIT_FAILURE.
 */
static int device_discovery()
{
   char buf[HPMUD_LINE_SIZE*64];
   int cnt=0, bytes_read, r=EXIT_FAILURE;
   enum HPMUD_RESULT stat;

   stat = hpmud_probe_devices(HPMUD_BUS_ALL, buf, sizeof(buf), &cnt, &bytes_read);

   if (stat != HPMUD_R_OK)
      goto bugout;

   if (cnt == 0)
   {
#ifdef HAVE_CUPS11
      fprintf(stdout, "direct hp:/no_device_found \"Unknown\" \"hp no_device_found\"\n");
#else
      fprintf(stdout, "direct hp \"Unknown\" \"HP Printer (HPLIP)\"\n");
#endif
      goto bugout;
   }
   else
      fprintf(stdout, "%s", buf);

   r = EXIT_SUCCESS;

bugout:
   return r;
}

static int open_device(const char* device_uri)
{
    //int io_mode = 0;
    HPMUD_DEVICE device_id = -1;
    int result_code = 0, r = EXIT_FAILURE;

    enum HPMUD_IO_MODE io_mode = HPMUD_RAW_MODE;

    debug("I/O mode=%d\n", io_mode);

    // 打开设备获得
    result_code = hpmud_open_device(device_uri, io_mode, &device_id);
    if (result_code != HPMUD_R_OK)
    {
        fprintf(stderr, "error opening device (code=%d)\n", result_code);
        goto bugout;
    }

    hd = device_id; //TODO:delect.
    r = EXIT_SUCCESS;

bugout:
    return r;
}


/* Map printer status to IPP printer-state-reasons (see RFC-2911). */
static int map_ipp_printer_state_reason(int status, const char **state_msg)
{

   if (status >= 1000 && status <= 1999)
   {
      /* inkjet vstatus */
      switch (status)
      {
         case VSTATUS_IDLE:
         case VSTATUS_PRNT:
            *state_msg = "none";
            break;
         case VSTATUS_OOPA:
            *state_msg = "media-empty-error";
            break;
         case(VSTATUS_PAJM):
            *state_msg = "media-jam-error";
            break;
         default:
            *state_msg = "other";
            break;
      }
   }
   else if (status >= 10000 && status <= 55999)
   {
      /* laserjet pjl status */
      if (status >= 10000 && status <= 10999)
         *state_msg = "none";
      else if (status >= 41000 && status <= 41999)
         *state_msg = "media-empty-error";
      else if ((status >= 42000 && status <= 42999) || (status >= 44000 && status <= 44999) || (status == 40022))
         *state_msg = "media-jam-error";
      else if (status == 40021)
         *state_msg = "cover-open-error";
      else if (status == 40600)
         *state_msg = "toner-empty-error";
      else
         *state_msg = "other";      /* 40017 - cartridge E-LABEL is unreadable (ie: ljp1005) */
   }
   else
   {
      /* Assume hpmud error */
      *state_msg = "other";
   }

   return 0;
}

/*
 * get_printer_status
 *
 * inputs:
 *   dd - device descriptor
 *   pa - see pjl_attributes definition
 *
 * outputs:
 *   return - printer status, 1000 to 1999 = inkjet vstatus, 5000 to 5999 = hpmud error, 10000 to 55999 = pjl status code
 *
 */
static int get_printer_status(HPMUD_DEVICE dd, HPMUD_CHANNEL cd, struct pjl_attributes *pa)
{
   char id[1024];
   char *pSf;
   int status, ver, len;
   enum HPMUD_RESULT r;

   if (pa->pjl_device)
   {
      pthread_mutex_lock(&pa->mutex);
      status = pa->current_status;
      pthread_mutex_unlock(&pa->mutex);
   }
   else
   {
      status = VSTATUS_IDLE; /* set default */
      r = hpmud_get_device_id(dd, id, sizeof(id), &len);
//      if (!(r == HPMUD_R_OK || r == HPMUD_R_DEVICE_BUSY))
      if (r != HPMUD_R_OK)
      {
         status = 5000+r;      /* no deviceid, return some error */
         goto bugout;
      }

      /* Check for valid S-field in device id string. */
      if ((pSf = strstr(id, ";S:")) == NULL)
      {
         /* No S-field, use status register instead of device id. */
         unsigned int bit_status;
         r = hpmud_get_device_status(dd, &bit_status);
//         if (!(r == HPMUD_R_OK || r == HPMUD_R_DEVICE_BUSY))
         if (r != HPMUD_R_OK)
         {
            status = 5000+r;      /* no 8-bit status, return some error */
            goto bugout;
         }

         if (DEVICE_IS_OOP(bit_status))
            status = VSTATUS_OOPA;
         else if (DEVICE_PAPER_JAMMED(bit_status))
            status = VSTATUS_PAJM;
         else if (DEVICE_IO_TRAP(bit_status))
            status = VSTATUS_CARS;
      }
      else
      {
         /* Valid S-field, get version number. */
         pSf+=3;
         ver = 0;
         HEX2INT(*pSf, ver);
         pSf++;
         ver = ver << 4;
         HEX2INT(*pSf, ver);
         pSf++;

         /* Position pointer to printer state subfield. */
         switch (ver)
         {
            case 0:
            case 1:
            case 2:
               pSf+=12;
               break;
            case 3:
               pSf+=14;
               break;
            case 4:
               pSf+=18;
               break;
            default:
               BUG("WARNING: unknown S-field version=%d\n", ver);
               pSf+=12;
               break;
         }

         /* Extract VStatus.*/
         status = 0;
         HEX2INT(*pSf, status);
         pSf++;
         status = status << 4;
         HEX2INT(*pSf, status);
         status += 1000;
      }
   }

bugout:
   return status;
}


/* Check printer status, if a valid error state, loop until error condition is cleared. */
static int loop_test(HPMUD_DEVICE dd, HPMUD_CHANNEL cd, struct pjl_attributes *pa,
        const char *dev, const char *printer, const char *username, const char *jobid, const char *title)
{
   int status, stat;
   const char *pstate, *old_state=NULL;

   while (1)
   {
      status = get_printer_status(dd, cd, pa);
      map_ipp_printer_state_reason(status, &pstate);

      /* Check for user intervention errors. */
      if (strstr(pstate, "error"))
      {
         if (pstate != old_state)
         {
            if (old_state)
            {
               /* Clear old error. */
//               device_event(dev, printer, status, username, jobid, title);
               fprintf(stderr, "STATE: -%s\n", old_state);
            }

            /* Display error. */
            //device_event(dev, printer, status, username, jobid, title);
            fprintf(stderr, "STATE: +%s\n", pstate);
            old_state = pstate;
         }
         BUG("ERROR: %d %s; will retry in %d seconds...\n", status, pstate, RETRY_TIMEOUT);
         sleep(RETRY_TIMEOUT);
         continue;
      }

      /* Clear any old state. */
      if (old_state)
         fprintf(stderr, "STATE: -%s\n", old_state);

      /* Check for system errors. */
      if (status >= 5000 && status <= 5999)
      {
         /* Display error. */
         //device_event(dev, printer, status, username, jobid, title);
         BUG("ERROR: %d device communication error!\n", status);
         stat = 1;
      }
      else
         stat = 0;

      break;   /* done */
   }

   return stat;
}

int get_device_id(HPMUD_DEVICE hd)
{
    char id[1024] = {0};
    char *pSf;
    int status, ver, len;
    enum HPMUD_RESULT r;
    int ret = EXIT_FAILURE;
    r = hpmud_get_device_id(hd, id,sizeof(id), &len);
    printf("device_id:%s\n", id);
    if (r != HPMUD_R_OK)
    {
       /* no deviceid, return some error */
       goto bugout;
    }
    /* Check for valid S-field in device id string. */
    if ((pSf = strstr(id, ";S:")) == NULL)
    {
       /* No S-field, use status register instead of device id. */
       unsigned int bit_status;
       r = hpmud_get_device_status(hd, &bit_status);
//         if (!(r == HPMUD_R_OK || r == HPMUD_R_DEVICE_BUSY))
       if (r != HPMUD_R_OK)
       {
          status = 5000+r;      /* no 8-bit status, return some error */
          goto bugout;
       }

//       if (DEVICE_IS_OOP(bit_status))
//          status = VSTATUS_OOPA;
//       else if (DEVICE_PAPER_JAMMED(bit_status))
//          status = VSTATUS_PAJM;
//       else if (DEVICE_IO_TRAP(bit_status))
//          status = VSTATUS_CARS;
    }
    else
    {
       /* Valid S-field, get version number. */
       pSf+=3;
       ver = 0;
       HEX2INT(*pSf, ver);
       pSf++;
       ver = ver << 4;
       HEX2INT(*pSf, ver);
       pSf++;

       /* Position pointer to printer state subfield. */
       switch (ver)
       {
          case 0:
          case 1:
          case 2:
             pSf+=12;
             break;
          case 3:
             pSf+=14;
             break;
          case 4:
             pSf+=18;
             break;
          default:
             printf("WARNING: unknown S-field version=%d\n", ver);
             pSf+=12;
             break;
       }

       /* Extract VStatus.*/
       status = 0;
       HEX2INT(*pSf, status);
       pSf++;
       status = status << 4;
       HEX2INT(*pSf, status);
       status += 1000;
    }
    printf("status:%d\n", status);
    ret = EXIT_SUCCESS;
bugout:
    return ret;
}

static int get_printer_status_code(const char* device_id)
{
	const char* id = device_id;
    char *pSf;
    int ver;
    int status = 0;

    /* Check for valid S-field in device id string. */
    if ((pSf = strstr(id, ";S:")) == NULL)
    {
    	/* No S-field, use status register instead of device id. */
    	/* do nothing */
    	goto bugout;
    }
    else
    {
       /* Valid S-field, get version number. */
       pSf+=3;
       ver = 0;
       HEX2INT(*pSf, ver);
       pSf++;
       ver = ver << 4;
       HEX2INT(*pSf, ver);
       pSf++;

       /* Position pointer to printer state subfield. */
       switch (ver)
       {
          case 0:
          case 1:
          case 2:
             pSf+=12;
             break;
          case 3:
             pSf+=14;
             break;
          case 4:
             pSf+=18;
             break;
          default:
             printf("WARNING: unknown S-field version=%d\n", ver);
             pSf+=12;
             break;
       }

       /* Extract VStatus.*/
       status = 0;
       HEX2INT(*pSf, status);
       pSf++;
       status = status << 4;
       HEX2INT(*pSf, status);
       status += 1000;
    }
    printf("status:%d\n", status);

bugout:
    return status;
}

static int get_cups_uri(char* cups_uri)
{
    char buf[HPMUD_LINE_SIZE*64];
    int cnt=0, bytes_read, r=EXIT_FAILURE;
    enum HPMUD_RESULT stat;

    stat = hpmud_probe_devices(HPMUD_BUS_ALL, buf, sizeof(buf), &cnt, &bytes_read);

    if (stat != HPMUD_R_OK)
      goto bugout;

    if (cnt == 0)
        fprintf(stdout, "direct hp \"Unknown\" \"HP Printer (HPLIP)\"\n");
    else
        sprintf(cups_uri, buf, strlen(buf));

    r = EXIT_SUCCESS;

bugout:
    return r;
}


static int make_device_uri(char* dev_uri)
{
    int ret = EXIT_FAILURE;
    enum HPMUD_RESULT stat;
    char cups_uri[HPMUD_LINE_SIZE*64];
    char* p = NULL;

    stat = get_cups_uri(cups_uri);

    if (stat != EXIT_SUCCESS)
      goto bugout;

    p = strtok(cups_uri, " ");
    if(p == NULL)
        goto bugout;

    p = strtok(NULL, " ");
    if(p == NULL)
        goto bugout;

    // copy only one device uri and others ignore.
    sprintf(dev_uri, p, strlen(p));

    debug("dev_uri:%s\n", dev_uri);

    ret = EXIT_SUCCESS;
bugout:
    return ret;
}

int main(void)
{
    int ret = EXIT_FAILURE;
    //const char *device_uri = "hp:/usb/Deskjet_1010_series?serial=CN39I18M1805S8";
    //const char *device_uri = "hp:/usb/Deskjet_1000_J110_series?serial=CN2C818N3605YD";
    char dev_uri[HPMUD_LINE_SIZE] = {0};

    // step 1.
    if(device_discovery() != EXIT_SUCCESS)
    {
        debug("device discovery failed!\n");
        goto bugout;
    }
    printf("device discovery success!\n");

    // step 2:解析一个device uri.
    if(make_device_uri(dev_uri) !=  EXIT_SUCCESS)
    {
        debug("make device uri failed!\n");
        goto bugout;
    }

    // step 3:open hp device
    if(open_device(dev_uri) !=  EXIT_SUCCESS)
    {
        debug("open_device device failed!\n");
        goto bugout;
    }

    // step 4: get device id.
    get_device_id(hd);

    //printData();

    //readAttributeFromXml_EWS

    //StatusType10();

    char* reply = (char*)MALLOC(char, 500*1024);

    //获取状态XML
    getEWSUrl_LEDM("/DevMgmt/ProductStatusDyn.xml", reply);  // 获取状态
    //getEWSUrl_LEDM("/DevMgmt/ConsumableConfigDyn.xml", reply); // 获取耗材配置

    free(reply);
    reply = NULL;

    if (hd >= 0)
       hpmud_close_device(hd);

    ret = EXIT_SUCCESS;

bugout:
    return ret;
}

打印机异常状态：

N	Windows状态	宏
0	正常	STATUS_PRINTER_IDLE(1000)
1	无法与打印机通信	x
2	出纸盒已关闭	STATUS_PRINTER_OUTPUT_TRAY_CLOSED(1035)
3	门己打开	STATUS_PRINTER_PEN_CHANGE(1008)
4	缺纸	STATUS_PRINTER_OUT_OF_PAPER(1009)
5	卡纸	STATUS_PRINTER_PAPER_STALL(1016)
6	墨盒故障-黑色	STATUS_PRINTER_PEN_FAILURE(1017)
7	墨盒故障-三色	-
8	墨盒故障-黑色-三色	-
9	墨盒丢失	-
10	单墨盒模式-缺黑色	STATUS_PRINTER_IDLE(1000)
11	单墨盒模式-缺彩色	STATUS_PRINTER_IDLE(1000)
12	无墨黑色	x
13	无墨彩色	x
14	无墨黑色-彩色	x
15	已经安装HP保护墨盒	x
16	检測到使用过的或仿制墨盒	x
	...
注：x代表暂无条件获取, -代表和上条同样。假设出现6号状态，建议提示提示语“墨盒故障或墨盒丢失”。

本文转自mfrbuaa博客园博客，原文链接：http://www.cnblogs.com/mfrbuaa/p/5065783.html，如需转载请自行联系原作者