profiles/cups/hcrp.c - vendor/opensource/bluez - Git at Google

 /*
  *
  *  BlueZ - Bluetooth protocol stack for Linux
  *
  *  Copyright (C) 2003-2010  Marcel Holtmann <marcel@holtmann.org>
  *
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program 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 this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  *
  */

 #ifdef HAVE_CONFIG_H
 #include <config.h>
 #endif

 #include <stdio.h>
 #include <errno.h>
 #include <unistd.h>
 #include <string.h>
 #include <signal.h>
 #include <sys/socket.h>
 #include <netinet/in.h>

 #include "lib/bluetooth.h"
 #include "lib/l2cap.h"
 #include "lib/sdp.h"
 #include "lib/sdp_lib.h"

 #include "cups.h"

 #define HCRP_PDU_CREDIT_GRANT		0x0001
 #define HCRP_PDU_CREDIT_REQUEST		0x0002
 #define HCRP_PDU_GET_LPT_STATUS		0x0005

 #define HCRP_STATUS_FEATURE_UNSUPPORTED	0x0000
 #define HCRP_STATUS_SUCCESS		0x0001
 #define HCRP_STATUS_CREDIT_SYNC_ERROR	0x0002
 #define HCRP_STATUS_GENERIC_FAILURE	0xffff

 struct hcrp_pdu_hdr {
 	uint16_t pid;
 	uint16_t tid;
 	uint16_t plen;
 } __attribute__ ((packed));
 #define HCRP_PDU_HDR_SIZE 6

 struct hcrp_credit_grant_cp {
 	uint32_t credit;
 } __attribute__ ((packed));
 #define HCRP_CREDIT_GRANT_CP_SIZE 4

 struct hcrp_credit_grant_rp {
 	uint16_t status;
 } __attribute__ ((packed));
 #define HCRP_CREDIT_GRANT_RP_SIZE 2

 struct hcrp_credit_request_rp {
 	uint16_t status;
 	uint32_t credit;
 } __attribute__ ((packed));
 #define HCRP_CREDIT_REQUEST_RP_SIZE 6

 struct hcrp_get_lpt_status_rp {
 	uint16_t status;
 	uint8_t  lpt_status;
 } __attribute__ ((packed));
 #define HCRP_GET_LPT_STATUS_RP_SIZE 3

 static int hcrp_credit_grant(int sk, uint16_t tid, uint32_t credit)
 {
 	struct hcrp_pdu_hdr hdr;
 	struct hcrp_credit_grant_cp cp;
 	struct hcrp_credit_grant_rp rp;
 	unsigned char buf[128];
 	int len;

 	hdr.pid = htons(HCRP_PDU_CREDIT_GRANT);
 	hdr.tid = htons(tid);
 	hdr.plen = htons(HCRP_CREDIT_GRANT_CP_SIZE);
 	cp.credit = credit;
 	memcpy(buf, &hdr, HCRP_PDU_HDR_SIZE);
 	memcpy(buf + HCRP_PDU_HDR_SIZE, &cp, HCRP_CREDIT_GRANT_CP_SIZE);
 	len = write(sk, buf, HCRP_PDU_HDR_SIZE + HCRP_CREDIT_GRANT_CP_SIZE);
 	if (len < 0)
 		return len;

 	len = read(sk, buf, sizeof(buf));
 	if (len < 0)
 		return len;

 	memcpy(&hdr, buf, HCRP_PDU_HDR_SIZE);
 	memcpy(&rp, buf + HCRP_PDU_HDR_SIZE, HCRP_CREDIT_GRANT_RP_SIZE);

 	if (ntohs(rp.status) != HCRP_STATUS_SUCCESS) {
 		errno = EIO;
 		return -1;
 	}

 	return 0;
 }

 static int hcrp_credit_request(int sk, uint16_t tid, uint32_t *credit)
 {
 	struct hcrp_pdu_hdr hdr;
 	struct hcrp_credit_request_rp rp;
 	unsigned char buf[128];
 	int len;

 	hdr.pid = htons(HCRP_PDU_CREDIT_REQUEST);
 	hdr.tid = htons(tid);
 	hdr.plen = htons(0);
 	memcpy(buf, &hdr, HCRP_PDU_HDR_SIZE);
 	len = write(sk, buf, HCRP_PDU_HDR_SIZE);
 	if (len < 0)
 		return len;

 	len = read(sk, buf, sizeof(buf));
 	if (len < 0)
 		return len;

 	memcpy(&hdr, buf, HCRP_PDU_HDR_SIZE);
 	memcpy(&rp, buf + HCRP_PDU_HDR_SIZE, HCRP_CREDIT_REQUEST_RP_SIZE);

 	if (ntohs(rp.status) != HCRP_STATUS_SUCCESS) {
 		errno = EIO;
 		return -1;
 	}

 	if (credit)
 		*credit = ntohl(rp.credit);

 	return 0;
 }

 static int hcrp_get_lpt_status(int sk, uint16_t tid, uint8_t *lpt_status)
 {
 	struct hcrp_pdu_hdr hdr;
 	struct hcrp_get_lpt_status_rp rp;
 	unsigned char buf[128];
 	int len;

 	hdr.pid = htons(HCRP_PDU_GET_LPT_STATUS);
 	hdr.tid = htons(tid);
 	hdr.plen = htons(0);
 	memcpy(buf, &hdr, HCRP_PDU_HDR_SIZE);
 	len = write(sk, buf, HCRP_PDU_HDR_SIZE);
 	if (len < 0)
 		return len;

 	len = read(sk, buf, sizeof(buf));
 	if (len < 0)
 		return len;

 	memcpy(&hdr, buf, HCRP_PDU_HDR_SIZE);
 	memcpy(&rp, buf + HCRP_PDU_HDR_SIZE, HCRP_GET_LPT_STATUS_RP_SIZE);

 	if (ntohs(rp.status) != HCRP_STATUS_SUCCESS) {
 		errno = EIO;
 		return -1;
 	}

 	if (lpt_status)
 		*lpt_status = rp.lpt_status;

 	return 0;
 }

 static inline int hcrp_get_next_tid(int tid)
 {
 	if (tid > 0xf000)
 		return 0;
 	else
 		return tid + 1;
 }

 int hcrp_print(bdaddr_t *src, bdaddr_t *dst, unsigned short ctrl_psm, unsigned short data_psm, int fd, int copies, const char *cups_class)
 {
 	struct sockaddr_l2 addr;
 	struct l2cap_options opts;
 	socklen_t size;
 	unsigned char buf[2048];
 	int i, ctrl_sk, data_sk, count, len, timeout = 0;
 	unsigned int mtu;
 	uint8_t status;
 	uint16_t tid = 0;
 	uint32_t tmp, credit = 0;

 	if ((ctrl_sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0) {
 		perror("ERROR: Can't create socket");
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	memset(&addr, 0, sizeof(addr));
 	addr.l2_family = AF_BLUETOOTH;
 	bacpy(&addr.l2_bdaddr, src);

 	if (bind(ctrl_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 		perror("ERROR: Can't bind socket");
 		close(ctrl_sk);
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	memset(&addr, 0, sizeof(addr));
 	addr.l2_family = AF_BLUETOOTH;
 	bacpy(&addr.l2_bdaddr, dst);
 	addr.l2_psm = htobs(ctrl_psm);

 	if (connect(ctrl_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 		perror("ERROR: Can't connect to device");
 		close(ctrl_sk);
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	if ((data_sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0) {
 		perror("ERROR: Can't create socket");
 		close(ctrl_sk);
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	memset(&addr, 0, sizeof(addr));
 	addr.l2_family = AF_BLUETOOTH;
 	bacpy(&addr.l2_bdaddr, src);

 	if (bind(data_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 		perror("ERROR: Can't bind socket");
 		close(data_sk);
 		close(ctrl_sk);
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	memset(&addr, 0, sizeof(addr));
 	addr.l2_family = AF_BLUETOOTH;
 	bacpy(&addr.l2_bdaddr, dst);
 	addr.l2_psm = htobs(data_psm);

 	if (connect(data_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 		perror("ERROR: Can't connect to device");
 		close(data_sk);
 		close(ctrl_sk);
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	fputs("STATE: -connecting-to-device\n", stderr);

 	memset(&opts, 0, sizeof(opts));
 	size = sizeof(opts);

 	if (getsockopt(data_sk, SOL_L2CAP, L2CAP_OPTIONS, &opts, &size) < 0) {
 		perror("ERROR: Can't get socket options");
 		close(data_sk);
 		close(ctrl_sk);
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	mtu = opts.omtu;

 	/* Ignore SIGTERM signals if printing from stdin */
 	if (fd == 0) {
 #ifdef HAVE_SIGSET
 		sigset(SIGTERM, SIG_IGN);
 #elif defined(HAVE_SIGACTION)
 		memset(&action, 0, sizeof(action));
 		sigemptyset(&action.sa_mask);
 		action.sa_handler = SIG_IGN;
 		sigaction(SIGTERM, &action, NULL);
 #else
 		signal(SIGTERM, SIG_IGN);
 #endif /* HAVE_SIGSET */
 	}

 	tid = hcrp_get_next_tid(tid);
 	if (hcrp_credit_grant(ctrl_sk, tid, 0) < 0) {
 		fprintf(stderr, "ERROR: Can't grant initial credits\n");
 		close(data_sk);
 		close(ctrl_sk);
 		if (cups_class)
 			return CUPS_BACKEND_FAILED;
 		else
 			return CUPS_BACKEND_RETRY;
 	}

 	for (i = 0; i < copies; i++) {

 		if (fd != 0) {
 			fprintf(stderr, "PAGE: 1 1\n");
 			lseek(fd, 0, SEEK_SET);
 		}

 		while (1) {
 			if (credit < mtu) {
 				tid = hcrp_get_next_tid(tid);
 				if (!hcrp_credit_request(ctrl_sk, tid, &tmp)) {
 					credit += tmp;
 					timeout = 0;
 				}
 			}

 			if (!credit) {
 				if (timeout++ > 300) {
 					tid = hcrp_get_next_tid(tid);
 					if (!hcrp_get_lpt_status(ctrl_sk, tid, &status))
 						fprintf(stderr, "ERROR: LPT status 0x%02x\n", status);
 					break;
 				}

 				sleep(1);
 				continue;
 			}

 			count = read(fd, buf, (credit > mtu) ? mtu : credit);
 			if (count <= 0)
 				break;

 			len = write(data_sk, buf, count);
 			if (len < 0) {
 				perror("ERROR: Error writing to device");
 				close(data_sk);
 				close(ctrl_sk);
 				return CUPS_BACKEND_FAILED;
 			}

 			if (len != count)
 				fprintf(stderr, "ERROR: Can't send complete data\n");

 			credit -= len;
 		}

 	}

 	close(data_sk);
 	close(ctrl_sk);

 	return CUPS_BACKEND_OK;
 }
	/*
	*
	* BlueZ - Bluetooth protocol stack for Linux
	*
	* Copyright (C) 2003-2010 Marcel Holtmann <marcel@holtmann.org>
	*
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program 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 this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*
	*/

	#ifdef HAVE_CONFIG_H
	#include <config.h>
	#endif

	#include <stdio.h>
	#include <errno.h>
	#include <unistd.h>
	#include <string.h>
	#include <signal.h>
	#include <sys/socket.h>
	#include <netinet/in.h>

	#include "lib/bluetooth.h"
	#include "lib/l2cap.h"
	#include "lib/sdp.h"
	#include "lib/sdp_lib.h"

	#include "cups.h"

	#define HCRP_PDU_CREDIT_GRANT 0x0001
	#define HCRP_PDU_CREDIT_REQUEST 0x0002
	#define HCRP_PDU_GET_LPT_STATUS 0x0005

	#define HCRP_STATUS_FEATURE_UNSUPPORTED 0x0000
	#define HCRP_STATUS_SUCCESS 0x0001
	#define HCRP_STATUS_CREDIT_SYNC_ERROR 0x0002
	#define HCRP_STATUS_GENERIC_FAILURE 0xffff

	struct hcrp_pdu_hdr {
	uint16_t pid;
	uint16_t tid;
	uint16_t plen;
	} __attribute__ ((packed));
	#define HCRP_PDU_HDR_SIZE 6

	struct hcrp_credit_grant_cp {
	uint32_t credit;
	} __attribute__ ((packed));
	#define HCRP_CREDIT_GRANT_CP_SIZE 4

	struct hcrp_credit_grant_rp {
	uint16_t status;
	} __attribute__ ((packed));
	#define HCRP_CREDIT_GRANT_RP_SIZE 2

	struct hcrp_credit_request_rp {
	uint16_t status;
	uint32_t credit;
	} __attribute__ ((packed));
	#define HCRP_CREDIT_REQUEST_RP_SIZE 6

	struct hcrp_get_lpt_status_rp {
	uint16_t status;
	uint8_t lpt_status;
	} __attribute__ ((packed));
	#define HCRP_GET_LPT_STATUS_RP_SIZE 3

	static int hcrp_credit_grant(int sk, uint16_t tid, uint32_t credit)
	{
	struct hcrp_pdu_hdr hdr;
	struct hcrp_credit_grant_cp cp;
	struct hcrp_credit_grant_rp rp;
	unsigned char buf[128];
	int len;

	hdr.pid = htons(HCRP_PDU_CREDIT_GRANT);
	hdr.tid = htons(tid);
	hdr.plen = htons(HCRP_CREDIT_GRANT_CP_SIZE);
	cp.credit = credit;
	memcpy(buf, &hdr, HCRP_PDU_HDR_SIZE);
	memcpy(buf + HCRP_PDU_HDR_SIZE, &cp, HCRP_CREDIT_GRANT_CP_SIZE);
	len = write(sk, buf, HCRP_PDU_HDR_SIZE + HCRP_CREDIT_GRANT_CP_SIZE);
	if (len < 0)
	return len;

	len = read(sk, buf, sizeof(buf));
	if (len < 0)
	return len;

	memcpy(&hdr, buf, HCRP_PDU_HDR_SIZE);
	memcpy(&rp, buf + HCRP_PDU_HDR_SIZE, HCRP_CREDIT_GRANT_RP_SIZE);

	if (ntohs(rp.status) != HCRP_STATUS_SUCCESS) {
	errno = EIO;
	return -1;
	}

	return 0;
	}

	static int hcrp_credit_request(int sk, uint16_t tid, uint32_t *credit)
	{
	struct hcrp_pdu_hdr hdr;
	struct hcrp_credit_request_rp rp;
	unsigned char buf[128];
	int len;

	hdr.pid = htons(HCRP_PDU_CREDIT_REQUEST);
	hdr.tid = htons(tid);
	hdr.plen = htons(0);
	memcpy(buf, &hdr, HCRP_PDU_HDR_SIZE);
	len = write(sk, buf, HCRP_PDU_HDR_SIZE);
	if (len < 0)
	return len;

	len = read(sk, buf, sizeof(buf));
	if (len < 0)
	return len;

	memcpy(&hdr, buf, HCRP_PDU_HDR_SIZE);
	memcpy(&rp, buf + HCRP_PDU_HDR_SIZE, HCRP_CREDIT_REQUEST_RP_SIZE);

	if (ntohs(rp.status) != HCRP_STATUS_SUCCESS) {
	errno = EIO;
	return -1;
	}

	if (credit)
	*credit = ntohl(rp.credit);

	return 0;
	}

	static int hcrp_get_lpt_status(int sk, uint16_t tid, uint8_t *lpt_status)
	{
	struct hcrp_pdu_hdr hdr;
	struct hcrp_get_lpt_status_rp rp;
	unsigned char buf[128];
	int len;

	hdr.pid = htons(HCRP_PDU_GET_LPT_STATUS);
	hdr.tid = htons(tid);
	hdr.plen = htons(0);
	memcpy(buf, &hdr, HCRP_PDU_HDR_SIZE);
	len = write(sk, buf, HCRP_PDU_HDR_SIZE);
	if (len < 0)
	return len;

	len = read(sk, buf, sizeof(buf));
	if (len < 0)
	return len;

	memcpy(&hdr, buf, HCRP_PDU_HDR_SIZE);
	memcpy(&rp, buf + HCRP_PDU_HDR_SIZE, HCRP_GET_LPT_STATUS_RP_SIZE);

	if (ntohs(rp.status) != HCRP_STATUS_SUCCESS) {
	errno = EIO;
	return -1;
	}

	if (lpt_status)
	*lpt_status = rp.lpt_status;

	return 0;
	}

	static inline int hcrp_get_next_tid(int tid)
	{
	if (tid > 0xf000)
	return 0;
	else
	return tid + 1;
	}

	int hcrp_print(bdaddr_t src, bdaddr_t dst, unsigned short ctrl_psm, unsigned short data_psm, int fd, int copies, const char *cups_class)
	{
	struct sockaddr_l2 addr;
	struct l2cap_options opts;
	socklen_t size;
	unsigned char buf[2048];
	int i, ctrl_sk, data_sk, count, len, timeout = 0;
	unsigned int mtu;
	uint8_t status;
	uint16_t tid = 0;
	uint32_t tmp, credit = 0;

	if ((ctrl_sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0) {
	perror("ERROR: Can't create socket");
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	memset(&addr, 0, sizeof(addr));
	addr.l2_family = AF_BLUETOOTH;
	bacpy(&addr.l2_bdaddr, src);

	if (bind(ctrl_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
	perror("ERROR: Can't bind socket");
	close(ctrl_sk);
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	memset(&addr, 0, sizeof(addr));
	addr.l2_family = AF_BLUETOOTH;
	bacpy(&addr.l2_bdaddr, dst);
	addr.l2_psm = htobs(ctrl_psm);

	if (connect(ctrl_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
	perror("ERROR: Can't connect to device");
	close(ctrl_sk);
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	if ((data_sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0) {
	perror("ERROR: Can't create socket");
	close(ctrl_sk);
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	memset(&addr, 0, sizeof(addr));
	addr.l2_family = AF_BLUETOOTH;
	bacpy(&addr.l2_bdaddr, src);

	if (bind(data_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
	perror("ERROR: Can't bind socket");
	close(data_sk);
	close(ctrl_sk);
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	memset(&addr, 0, sizeof(addr));
	addr.l2_family = AF_BLUETOOTH;
	bacpy(&addr.l2_bdaddr, dst);
	addr.l2_psm = htobs(data_psm);

	if (connect(data_sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
	perror("ERROR: Can't connect to device");
	close(data_sk);
	close(ctrl_sk);
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	fputs("STATE: -connecting-to-device\n", stderr);

	memset(&opts, 0, sizeof(opts));
	size = sizeof(opts);

	if (getsockopt(data_sk, SOL_L2CAP, L2CAP_OPTIONS, &opts, &size) < 0) {
	perror("ERROR: Can't get socket options");
	close(data_sk);
	close(ctrl_sk);
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	mtu = opts.omtu;

	/* Ignore SIGTERM signals if printing from stdin */
	if (fd == 0) {
	#ifdef HAVE_SIGSET
	sigset(SIGTERM, SIG_IGN);
	#elif defined(HAVE_SIGACTION)
	memset(&action, 0, sizeof(action));
	sigemptyset(&action.sa_mask);
	action.sa_handler = SIG_IGN;
	sigaction(SIGTERM, &action, NULL);
	#else
	signal(SIGTERM, SIG_IGN);
	#endif /* HAVE_SIGSET */
	}

	tid = hcrp_get_next_tid(tid);
	if (hcrp_credit_grant(ctrl_sk, tid, 0) < 0) {
	fprintf(stderr, "ERROR: Can't grant initial credits\n");
	close(data_sk);
	close(ctrl_sk);
	if (cups_class)
	return CUPS_BACKEND_FAILED;
	else
	return CUPS_BACKEND_RETRY;
	}

	for (i = 0; i < copies; i++) {

	if (fd != 0) {
	fprintf(stderr, "PAGE: 1 1\n");
	lseek(fd, 0, SEEK_SET);
	}

	while (1) {
	if (credit < mtu) {
	tid = hcrp_get_next_tid(tid);
	if (!hcrp_credit_request(ctrl_sk, tid, &tmp)) {
	credit += tmp;
	timeout = 0;
	}
	}

	if (!credit) {
	if (timeout++ > 300) {
	tid = hcrp_get_next_tid(tid);
	if (!hcrp_get_lpt_status(ctrl_sk, tid, &status))
	fprintf(stderr, "ERROR: LPT status 0x%02x\n", status);
	break;
	}

	sleep(1);
	continue;
	}

	count = read(fd, buf, (credit > mtu) ? mtu : credit);
	if (count <= 0)
	break;

	len = write(data_sk, buf, count);
	if (len < 0) {
	perror("ERROR: Error writing to device");
	close(data_sk);
	close(ctrl_sk);
	return CUPS_BACKEND_FAILED;
	}

	if (len != count)
	fprintf(stderr, "ERROR: Can't send complete data\n");

	credit -= len;
	}

	}

	close(data_sk);
	close(ctrl_sk);

	return CUPS_BACKEND_OK;
	}