ptp.c

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

 * Switches the camera display to on and lets the user
 * select what to transfer. Sends a 0xc011 event when started 
 * and 0xc013 if direct transfer aborted.
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_initiate_direct_transfer (PTPParams* params, uint32_t *out)
{
	PTPContainer ptp;
	uint16_t ret;

	PTP_CNT_INIT(ptp);
	ptp.Code   = PTP_OC_CANON_InitiateDirectTransferEx2;
	ptp.Nparam = 1;
	ptp.Param1 = 0xf;
	ret = ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
	if ((ret == PTP_RC_OK) && (ptp.Nparam>0))
		*out = ptp.Param1;
	return ret;
}

/**
 * ptp_canon_get_target_handles:
 * params:	PTPParams*
 *              PTPCanon_directtransfer_entry **out
 *              unsigned int *outsize
 * 
 * Retrieves direct transfer entries specifying the images to transfer
 * from the camera (to be retrieved after 0xc011 event).
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_get_target_handles (PTPParams* params,
	PTPCanon_directtransfer_entry **entries, unsigned int *cnt)
{
	PTPContainer ptp;
	uint16_t ret;
	unsigned char *out = NULL, *cur;
	int i;
	unsigned int size;
	
	PTP_CNT_INIT(ptp);
	ptp.Code   = PTP_OC_CANON_GetTargetHandles;
	ptp.Nparam = 0;
	ret = ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &out, &size);
	if (ret != PTP_RC_OK)
		return ret;
	*cnt = dtoh32a(out);
	*entries = malloc(sizeof(PTPCanon_directtransfer_entry)*(*cnt));
	cur = out+4;
	for (i=0;i<*cnt;i++) {
		unsigned char len;
		(*entries)[i].oid = dtoh32a(cur);
		(*entries)[i].str = ptp_unpack_string(params, cur, 4, &len);
		cur += 4+(cur[4]*2+1);
	}
	free (out);
	return PTP_RC_OK;
}
/**
 * ptp_canon_endshootingmode:
 * params:	PTPParams*
 * 
 * This operation is observed after pressing the Disconnect 
 * button on the Remote Capture app. It emits a StorageInfoChanged 
 * event via the interrupt pipe and pushes the StorageInfoChanged
 * and CANON_CameraModeChange events onto the event stack
 * (see operation PTP_OC_CANON_CheckEvent).
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_endshootingmode (PTPParams* params)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_EndShootingMode;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_canon_viewfinderon:
 * params:	PTPParams*
 * 
 * Prior to start reading viewfinder images, one  must call this operation.
 * Supposedly, this operation affects the value of the CANON_ViewfinderMode
 * property.
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_viewfinderon (PTPParams* params)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_ViewfinderOn;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_canon_viewfinderoff:
 * params:	PTPParams*
 * 
 * Before changing the shooting mode, or when one doesn't need to read
 * viewfinder images any more, one must call this operation.
 * Supposedly, this operation affects the value of the CANON_ViewfinderMode
 * property.
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_viewfinderoff (PTPParams* params)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_ViewfinderOff;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_canon_aeafawb:
 * params:	PTPParams*
 * 		uint32_t p1 	- Yet unknown parameter,
 * 				  value 7 works
 * 
 * Called AeAfAwb (auto exposure, focus, white balance)
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_aeafawb (PTPParams* params, uint32_t p1)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_DoAeAfAwb;
	ptp.Param1=p1;
	ptp.Nparam=1;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}


/**
 * ptp_canon_checkevent:
 * params:	PTPParams*
 * 
 * The camera has a FIFO stack, in which it accumulates events.
 * Partially these events are communicated also via the USB interrupt pipe
 * according to the PTP USB specification, partially not.
 * This operation returns from the device a block of data, empty,
 * if the event stack is empty, or filled with an event's data otherwise.
 * The event is removed from the stack in the latter case.
 * The Remote Capture app sends this command to the camera all the time
 * of connection, filling with it the gaps between other operations. 
 *
 * Return values: Some PTP_RC_* code.
 * Upon success : PTPUSBEventContainer* event	- is filled with the event data
 *						  if any
 *                int *isevent			- returns 1 in case of event
 *						  or 0 otherwise
 **/
uint16_t
ptp_canon_checkevent (PTPParams* params, PTPUSBEventContainer* event, int* isevent)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char *evdata = NULL;
	unsigned int len;
	
	*isevent=0;
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_CheckEvent;
	ptp.Nparam=0;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &evdata, &len);
	if (evdata!=NULL) {
		if (ret == PTP_RC_OK) {
        		ptp_unpack_EC(params, evdata, event, len);
    			*isevent=1;
        	}
		free(evdata);
	}
	return ret;
}


/**
 * ptp_canon_focuslock:
 *
 * This operation locks the focus. It is followed by the CANON_GetChanges(?)
 * operation in the log. 
 * It affects the CANON_MacroMode property. 
 *
 * params:	PTPParams*
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_focuslock (PTPParams* params)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_FocusLock;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_canon_focusunlock:
 *
 * This operation unlocks the focus. It is followed by the CANON_GetChanges(?)
 * operation in the log. 
 * It sets the CANON_MacroMode property value to 1 (where it occurs in the log).
 * 
 * params:	PTPParams*
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_focusunlock (PTPParams* params)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_FocusUnlock;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_canon_initiatecaptureinmemory:
 * 
 * This operation starts the image capture according to the current camera
 * settings. When the capture has happened, the camera emits a CaptureComplete
 * event via the interrupt pipe and pushes the CANON_RequestObjectTransfer,
 * CANON_DeviceInfoChanged and CaptureComplete events onto the event stack
 * (see operation CANON_CheckEvent). From the CANON_RequestObjectTransfer
 * event's parameter one can learn the just captured image's ObjectHandle.
 * The image is stored in the camera's own RAM.
 * On the next capture the image will be overwritten!
 *
 * params:	PTPParams*
 *
 * Return values: Some PTP_RC_* code.
 *
 **/
uint16_t
ptp_canon_initiatecaptureinmemory (PTPParams* params)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_InitiateCaptureInMemory;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

uint16_t
ptp_canon_9012 (PTPParams* params)
{
	PTPContainer ptp;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=0x9012;
	ptp.Nparam=0;
	return ptp_transaction(params, &ptp, PTP_DP_NODATA, 0, NULL, NULL);
}

/**
 * ptp_canon_getpartialobject:
 *
 * This operation is used to read from the device a data 
 * block of an object from a specified offset.
 *
 * params:	PTPParams*
 *      uint32_t handle - the handle of the requested object
 *      uint32_t offset - the offset in bytes from the beginning of the object
 *      uint32_t size - the requested size of data block to read
 *      uint32_t pos - 1 for the first block, 2 - for a block in the middle,
 *                  3 - for the last block
 *
 * Return values: Some PTP_RC_* code.
 *      char **block - the pointer to the block of data read
 *      uint32_t* readnum - the number of bytes read
 *
 **/
uint16_t
ptp_canon_getpartialobject (PTPParams* params, uint32_t handle, 
				uint32_t offset, uint32_t size,
				uint32_t pos, unsigned char** block, 
				uint32_t* readnum)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char *data=NULL;
	unsigned int len;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_GetPartialObjectEx;
	ptp.Param1=handle;
	ptp.Param2=offset;
	ptp.Param3=size;
	ptp.Param4=pos;
	ptp.Nparam=4;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &data, &len);
	if (ret==PTP_RC_OK) {
		*block=data;
		*readnum=ptp.Param1;
	}
	return ret;
}

/**
 * ptp_canon_getviewfinderimage:
 *
 * This operation can be used to read the image which is currently
 * in the camera's viewfinder. The image size is 320x240, format is JPEG.
 * Of course, prior to calling this operation, one must turn the viewfinder
 * on with the CANON_ViewfinderOn command.
 * Invoking this operation many times, one can get live video from the camera!
 * 
 * params:	PTPParams*
 * 
 * Return values: Some PTP_RC_* code.
 *      char **image - the pointer to the read image
 *      unit32_t *size - the size of the image in bytes
 *
 **/
uint16_t
ptp_canon_getviewfinderimage (PTPParams* params, unsigned char** image, uint32_t* size)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned int len;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_GetViewfinderImage;
	ptp.Nparam=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, image, &len);
	if (ret==PTP_RC_OK) *size=ptp.Param1;
	return ret;
}

/**
 * ptp_canon_getchanges:
 *
 * This is an interesting operation, about the effect of which I am not sure.
 * This command is called every time when a device property has been changed 
 * with the SetDevicePropValue operation, and after some other operations.
 * This operation reads the array of Device Properties which have been changed
 * by the previous operation.
 * Probably, this operation is even required to make those changes work.
 *
 * params:	PTPParams*
 * 
 * Return values: Some PTP_RC_* code.
 *      uint16_t** props - the pointer to the array of changed properties
 *      uint32_t* propnum - the number of elements in the *props array
 *
 **/
uint16_t
ptp_canon_getchanges (PTPParams* params, uint16_t** props, uint32_t* propnum)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char* data=NULL;
	unsigned int len;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_GetChanges;
	ptp.Nparam=0;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &data, &len);
	if (ret == PTP_RC_OK)
        	*propnum=ptp_unpack_uint16_t_array(params,data,0,props);
	free(data);
	return ret;
}

/**
 * ptp_canon_getobjectinfo:
 *
 * This command reads a specified object's record in a device's filesystem,
 * or the records of all objects belonging to a specified folder (association).
 *  
 * params:	PTPParams*
 *      uint32_t store - StorageID,
 *      uint32_t p2 - Yet unknown (0 value works OK)
 *      uint32_t parent - Parent Object Handle
 *                      # If Parent Object Handle is 0xffffffff, 
 *                      # the Parent Object is the top level folder.
 *      uint32_t handle - Object Handle
 *                      # If Object Handle is 0, the records of all objects 
 *                      # belonging to the Parent Object are read.
 *                      # If Object Handle is not 0, only the record of this 
 *                      # Object is read.
 *
 * Return values: Some PTP_RC_* code.
 *      PTPCANONFolderEntry** entries - the pointer to the folder entry array
 *      uint32_t* entnum - the number of elements of the array
 *
 **/
uint16_t
ptp_canon_getobjectinfo (PTPParams* params, uint32_t store, uint32_t p2, 
			    uint32_t parent, uint32_t handle, 
			    PTPCANONFolderEntry** entries, uint32_t* entnum)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char *data = NULL;
	unsigned int len;
	
	PTP_CNT_INIT(ptp);
	ptp.Code=PTP_OC_CANON_GetObjectInfoEx;
	ptp.Param1=store;
	ptp.Param2=p2;
	ptp.Param3=parent;
	ptp.Param4=handle;
	ptp.Nparam=4;
	len=0;
	ret=ptp_transaction(params, &ptp, PTP_DP_GETDATA, 0, &data, &len);
	if (ret == PTP_RC_OK) {
		int i;
		*entnum=ptp.Param1;
		*entries=calloc(*entnum, sizeof(PTPCANONFolderEntry));
		if (*entries!=NULL) {
			for(i=0; i<(*entnum); i++)
				ptp_unpack_Canon_FE(params,
					data+i*PTP_CANON_FolderEntryLen,
					&((*entries)[i]) );
		} else {
			ret=PTP_ERROR_IO; /* Cannot allocate memory */
		}
	}
	free(data);
	return ret;
}

/**
 * ptp_canon_get_objecthandle_by_name:
 *
 * This command looks up the specified object on the camera.
 *
 * Format is "A:\\PATH".
 *
 * The 'A' is the VolumeLabel from GetStorageInfo,
 * my IXUS has "A" for the card and "V" for internal memory.
 *  
 * params:	PTPParams*
 *      char* name - path name
 *
 * Return values: Some PTP_RC_* code.
 *      uint32_t *oid - PTP object id.
 *
 **/
uint16_t
ptp_canon_get_objecthandle_by_name (PTPParams* params, char* name, uint32_t* objectid)
{
	uint16_t ret;
	PTPContainer ptp;
	unsigned char *data = NULL;
	uint8_t len;

	PTP_CNT_INIT (ptp);
	ptp.Code=PTP_OC_CANON_GetObjectHandleByName;
	ptp.Nparam=0;
	len=0;
	data = malloc (2*(strlen(name)+1)+2);
	memset (data, 0, 2*(strlen(name)+1)+2);
	ptp_pack_string (params, name, data, 0, &len);
	ret=ptp_transaction (params, &ptp, PTP_DP_SENDDATA, (len+1)*2+1, &data, NULL);
	free (data);
	*objectid = ptp.Param1;
	return ret;
}

/**
 * ptp_canon_get_customize_data:
 *
 * This command downloads the specified theme slot, including jpegs
 * and wav files.
 *  
 * params:	PTPParams*
 *      uint32_t themenr - nr of theme
 *
 * Return values: Some PTP_RC_* code.
 *      unsigned char **data - pointer to data pointer
 *      unsigned int  *size - size of data returned
 *
 **/
uint16_t
ptp_canon_get_customize_data (PTPParams* params, uint32_t themenr,
		unsigned char **data, unsigned int *size)
{
	PTPContainer ptp;

	*data = NULL;