ptp.c

Media transfer protocol implementation on POSIX. Have detailed readme on how to move to windows

	/* get response */
	CHECK_PTP_RC(params->getresp_func(params, ptp));
	if (ptp->Transaction_ID != params->transaction_id-1) {
		ptp_error (params,
			"PTP: Sequence number mismatch %d vs expected %d.",
			ptp->Transaction_ID, params->transaction_id-1
		);
		return PTP_ERROR_BADPARAM;
	}
	return ptp->Code;
}

static uint16_t
ptp_transaction (PTPParams* params, PTPContainer* ptp, 
		 uint16_t flags, unsigned int sendlen, unsigned char** data,
		 unsigned int *recvlen)
{
	return _ptp_transaction(params, ptp, flags, sendlen, data, -1, recvlen);
}

static uint16_t
ptp_transaction_fd (PTPParams* params, PTPContainer* ptp, 
		      uint16_t flags, unsigned int sendlen, 
		      int fd, unsigned int *recvlen)
{
	/*
	 * This dummy data needed since _ptp_transaction()
	 * will dereference the data argument
	 */
	unsigned char *dummydata = NULL;
	
	return _ptp_transaction(params, ptp, flags, sendlen, &dummydata, fd, recvlen);
}

/* Enets handling functions */

/* PTP Events wait for or check mode */
#define PTP_EVENT_CHECK			0x0000	/* waits for */
#define PTP_EVENT_CHECK_FAST		0x0001	/* checks */

static inline uint16_t
ptp_usb_event (PTPParams* params, PTPContainer* event, int wait)
{
	uint16_t ret;
	unsigned int rlen;
	PTPUSBEventContainer usbevent;
	PTP_CNT_INIT(usbevent);

	if ((params==NULL) || (event==NULL)) 
		return PTP_ERROR_BADPARAM;
	
	switch(wait) {
		case PTP_EVENT_CHECK:
			ret=params->check_int_func((unsigned char*)&usbevent,
				sizeof(usbevent), params->data, &rlen);
			break;
		case PTP_EVENT_CHECK_FAST:
			ret=params->check_int_fast_func((unsigned char*)
				&usbevent, sizeof(usbevent), params->data, &rlen);
			break;
		default:
			ret=PTP_ERROR_BADPARAM;
	}
	if (ret!=PTP_RC_OK) {
		ptp_error (params,
			"PTP: reading event an error 0x%04x occurred", ret);
		ret = PTP_ERROR_IO;
		/* reading event error is nonfatal (for example timeout) */
	}
	/* Only do the additional reads for "events". Canon IXUS 2 likes to
	 * send unrelated data.
	 */
	if (dtoh16(usbevent.type) == PTP_USB_CONTAINER_EVENT) {
		while (dtoh32(usbevent.length) > rlen) {
			unsigned int newrlen = 0;

			ret=params->check_int_fast_func(((unsigned char*)&usbevent)+rlen,
				dtoh32(usbevent.length)-rlen,params->data,&newrlen
			);
			if (ret != PTP_RC_OK)
				break;
			rlen+=newrlen;
		}
	}
	/* if we read anything over interrupt endpoint it must be an event */
	/* build an appropriate PTPContainer */
	event->Code=dtoh16(usbevent.code);
	event->SessionID=params->session_id;
	event->Transaction_ID=dtoh32(usbevent.trans_id);
	event->Param1=dtoh32(usbevent.param1);
	event->Param2=dtoh32(usbevent.param2);
	event->Param3=dtoh32(usbevent.param3);
	return ret;
}

uint16_t
ptp_usb_event_check (PTPParams* params, PTPContainer* event) {

	return ptp_usb_event (params, event, PTP_EVENT_CHECK_FAST);
}

uint16_t
ptp_usb_event_wait (PTPParams* params, PTPContainer* event) {

	return ptp_usb_event (params, event, PTP_EVENT_CHECK);
}

/**
 * PTP operation functions
 *
 * all ptp_ functions should take integer parameters
 * in host byte order!
 **/


/**
 * ptp_getdeviceinfo:
 * params:	PTPParams*
 *
 * Gets device info dataset and fills deviceinfo structure.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getdeviceinfo (PTPParams* params, PTPDeviceInfo* deviceinfo)
{
	uint16_t ret;
	unsigned int len;
	PTPContainer ptp;
	unsigned char* di=NULL;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetDeviceInfo;
	ptp.Nparam=0;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &di, &len);
	if (ret == PTP_RC_OK) ptp_unpack_DI(params, di, deviceinfo, len);
	free(di);
	return ret;
}


/**
 * ptp_opensession:
 * params:	PTPParams*
 * 		session			- session number 
 *
 * Establishes a new session.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_opensession (PTPParams* params, uint32_t session)
{
	uint16_t ret;
	PTPContainer ptp;

	ptp_debug(params,"PTP: Opening session");

	/* SessonID field of the operation dataset should always
	   be set to 0 for OpenSession request! */
	params->session_id=0x00000000;
	/* TransactionID should be set to 0 also! */
	params->transaction_id=0x0000000;
	/* zero out response packet buffer */
	params->response_packet = NULL;
	params->response_packet_size = 0;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_OpenSession;
	ptp.Param1=session;
	ptp.Nparam=1;
	ret=ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
	/* now set the global session id to current session number */
	params->session_id=session;
	return ret;
}

/**
 * ptp_closesession:
 * params:	PTPParams*
 *
 * Closes session.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_closesession (PTPParams* params)
{
	PTPContainer ptp;

	ptp_debug(params,"PTP: Closing session");

	/* free any dangling response packet */
	if (params->response_packet_size > 0) {
		free(params->response_packet);
		params->response_packet = NULL;
		params->response_packet_size = 0;
	}
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CloseSession;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_getststorageids:
 * params:	PTPParams*
 *
 * Gets array of StorageIDs and fills the storageids structure.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getstorageids (PTPParams* params, PTPStorageIDs* storageids)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned int len;
	unsigned char* sids=NULL;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetStorageIDs;
	ptp.Nparam=0;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &sids, &len);
	if (ret == PTP_RC_OK) ptp_unpack_SIDs(params, sids, storageids, len);
	free(sids);
	return ret;
}

/**
 * ptp_getststorageinfo:
 * params:	PTPParams*
 *		storageid		- StorageID
 *
 * Gets StorageInfo dataset of desired storage and fills storageinfo
 * structure.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getstorageinfo (PTPParams* params, uint32_t storageid,
			PTPStorageInfo* storageinfo)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char* si=NULL;
	unsigned int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetStorageInfo;
	ptp.Param1=storageid;
	ptp.Nparam=1;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &si, &len);
	if (ret == PTP_RC_OK) ptp_unpack_SI(params, si, storageinfo, len);
	free(si);
	return ret;
}

/**
 * ptp_formatstore:
 * params:	PTPParams*
 *              storageid		- StorageID
 *
 * Formats the storage on the device.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_formatstore (PTPParams* params, uint32_t storageid)
{
	PTPContainer ptp;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_FormatStore;
	ptp.Param1=storageid;
	ptp.Param2=PTP_FST_Undefined;
	ptp.Nparam=2;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_getobjecthandles:
 * params:	PTPParams*
 *		storage			- StorageID
 *		objectformatcode	- ObjectFormatCode (optional)
 *		associationOH		- ObjectHandle of Association for
 *					  wich a list of children is desired
 *					  (optional)
 *		objecthandles		- pointer to structute
 *
 * Fills objecthandles with structure returned by device.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getobjecthandles (PTPParams* params, uint32_t storage,
			uint32_t objectformatcode, uint32_t associationOH,
			PTPObjectHandles* objecthandles)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char* oh=NULL;
	unsigned int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetObjectHandles;
	ptp.Param1=storage;
	ptp.Param2=objectformatcode;
	ptp.Param3=associationOH;
	ptp.Nparam=3;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &oh, &len);
	if (ret == PTP_RC_OK) ptp_unpack_OH(params, oh, objecthandles, len);
	free(oh);
	return ret;
}

/**
 * ptp_getnumobjects:
 * params:	PTPParams*
 *		storage			- StorageID
 *		objectformatcode	- ObjectFormatCode (optional)
 *		associationOH		- ObjectHandle of Association for
 *					  wich a list of children is desired
 *					  (optional)
 *		numobs			- pointer to uint32_t that takes number of objects
 *
 * Fills numobs with number of objects on device.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getnumobjects (PTPParams* params, uint32_t storage,
			uint32_t objectformatcode, uint32_t associationOH,
			uint32_t* numobs)
{
	uint16_t ret;
	PTPContainer ptp;
	int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetObjectHandles;
	ptp.Param1=storage;
	ptp.Param2=objectformatcode;
	ptp.Param3=associationOH;
	ptp.Nparam=3;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
	if (ret == PTP_RC_OK) {
		if (ptp.Nparam >= 1)
			*numobs = ptp.Param1;
		else
			ret = PTP_RC_GeneralError;
	}
	return ret;
}

/**
 * ptp_getobjectinfo:
 * params:	PTPParams*
 *		handle			- Object handle
 *		objectinfo		- pointer to objectinfo that is returned
 *
 * Get objectinfo structure for handle from device.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getobjectinfo (PTPParams* params, uint32_t handle,
			PTPObjectInfo* objectinfo)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char* oi=NULL;
	unsigned int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetObjectInfo;
	ptp.Param1=handle;
	ptp.Nparam=1;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &oi, &len);
	if (ret == PTP_RC_OK) ptp_unpack_OI(params, oi, objectinfo, len);
	free(oi);
	return ret;
}

/**
 * ptp_getobject:
 * params:	PTPParams*
 *		handle			- Object handle
 *		object			- pointer to data area
 *
 * Get object 'handle' from device and store the data in newly
 * allocated 'object'.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getobject (PTPParams* params, uint32_t handle, unsigned char** object)
{
	PTPContainer ptp;
	unsigned int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetObject;
	ptp.Param1=handle;
	ptp.Nparam=1;
	len=0;
	return ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, object, &len);
}

/**
 * ptp_getobject_tofd:
 * params:	PTPParams*
 *		handle			- Object handle
 *		fd                      - File descriptor to write() to
 *
 * Get object 'handle' from device and write the data to the 
 * given file descriptor.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getobject_tofd (PTPParams* params, uint32_t handle, int fd)
{
	PTPContainer ptp;
	unsigned int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetObject;
	ptp.Param1=handle;
	ptp.Nparam=1;
	len=0;
	return ptp_transaction_fd(params, &ptp, PTP_DP_GETDATA, 0, fd, &len);
}

/**
 * ptp_getpartialobject:
 * params:	PTPParams*
 *		handle			- Object handle
 *		offset			- Offset into object
 *		maxbytes		- Maximum of bytes to read
 *		object			- pointer to data area
 *
 * Get object 'handle' from device and store the data in newly
 * allocated 'object'. Start from offset and read at most maxbytes.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getpartialobject (PTPParams* params, uint32_t handle, uint32_t offset,
			uint32_t maxbytes, unsigned char** object)
{
	PTPContainer ptp;
	unsigned int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetPartialObject;
	ptp.Param1=handle;
	ptp.Param2=offset;
	ptp.Param3=maxbytes;
	ptp.Nparam=3;
	len=0;
	return ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, object, &len);
}

/**
 * ptp_getthumb:
 * params:	PTPParams*
 *		handle			- Object handle
 *		object			- pointer to data area
 *
 * Get thumb for object 'handle' from device and store the data in newly
 * allocated 'object'.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_getthumb (PTPParams* params, uint32_t handle, unsigned char** object)
{
	PTPContainer ptp;
	unsigned int len;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_GetThumb;
	ptp.Param1=handle;
	ptp.Nparam=1;
	return ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, object, &len);
}

/**
 * ptp_deleteobject:
 * params:	PTPParams*
 *		handle			- object handle
 *		ofc			- object format code (optional)
 * 
 * Deletes desired objects.
 *
 * Return values: Some PTP_RC_* code.
 **/
uint16_t
ptp_deleteobject (PTPParams* params, uint32_t handle, uint32_t ofc)
{
	PTPContainer ptp;

	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_DeleteObject;
	ptp.Param1=handle;
	ptp.Param2=ofc;
	ptp.Nparam=2;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);