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/*
* Prototype file for a gpsmon monitor object.
*
* This file is Copyright (c) 2010-2018 by the GPSD project
* SPDX-License-Identifier: BSD-2-clause
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <ctype.h>
#include <stdarg.h>
#include <stdbool.h>
#include <assert.h>
#include <unistd.h>
#include "gpsd.h"
#include "bits.h"
#include "gpsmon.h"
/*
* Replace PROTO everywhere with the name of the GPSD driver describing
* the device you want to support.
*
* gpsmon basically sits in a loop reading packets, using the same layer
* as gpsd to dispatch on packet type to select an active device driver.
* Your monitor object will become the handler for incoming packets whenever
* the driver your object points at is selected.
*
* A comment following the method descriptions explains some available
* helper functions.
*/
extern const struct gps_type_t driver__proto_;
static bool PROTO_initialize(void)
{
/*
* This function is called when your monitor object is activated.
*
* When you enter it, two windows will be accessible to you; (1)
* devicewin, just below the status and command line at top of
* screen, and (2) packetwin, taking up the rest of the screen below
* it; packetwin will be enabled for scrolling. Note, however,
* that you cannot necessarily update packetwin safely, as it may be NULL
* if the screen has no lines left over after allocating devicewin;
* you'll need to check this in your code.
*
* Use this method to paint windowframes and legends on the
* freshly initialized device window. You can also use this
* method to send probes to the device, e.g. to elicit a response
* telling you firmware rev levels or whatever.
*/
/* return false if the window allocation failed; gpsmon will abort */
return true;
}
static void PROTO_update(void)
{
/*
* Called on each packet received. The packet will be accessible in
* session.lexer.outbuffer and the length in session.lexer.outbuflen.
* If the device is NMEA, session.driver.nmea.fields[] will contain the
* array of unconverted field strings, including the tag in slot zero
* but not including the checksum or trailing \r\n.
*
* Use this function to update devicewin. The packet will be echoed to
* packetwin immediately after this function is called; you can use this
* function to write a prefix on the line.
*
* Helpers available include (1) toff_update, for throwing the
* TOFF data from the last time fix on the screen, and (2)
* pps_update, for throwing the PPS data from the last 1PPS event on
* the screen, and
*/
}
static int PROTO_command(char line[])
{
/*
* Interpret a command line. Whatever characters the user types will
* be echoed in the command buffer at the top right of the display. When
* he/she presses enter the command line will be passed to this function
* for interpretation. Note: packet receipt is suspended while this
* function is executing.
*
* This method is optional. If you set the command method pointer to
* NULL, gpsmon will behave sanely, accepting no device-specific commands.
*
* It is a useful convention to use uppercase letters for
* driver-specific commands and leave lowercase ones for the
* generic gpsmon ones.
*/
assert(strlen(line));
/*
* Return COMMAND_UNKNOWN to tell gpsmon you can't interpret the line, and
* it will be passed to the generic command interpreter to be handled there.
* You can alse return COMMAND_MATCH to tell it you handled the command,
* or COMMAND_TERMINATE to tell gpsmon you handled it and gpsmon should
* terminate.
*/
return COMMAND_UNKNOWN;
}
static void PROTO_wrap(void)
{
/*
* Deinitialize any windows you created in PROTO_initialize.
* This will be called when gpsmon switches drivers due to seeing
* a new packet type.
*/
}
/*
* Use mmt = monitor method table as a suffix for naming these things
* Yours will need to be added to the monitor_objects table in gpsmon.c,
* then of course you need to link your module into gpsmon.
*/
const struct monitor_object_t PROTO_mmt = {
.initialize = PROTO_initialize,
.update = PROTO_update,
.command = PROTO_command,
.wrap = PROTO_wrap,
.min_y = 23, .min_x = 80, /* size of the device window */
/*
* The gpsd driver type for your device. gpsmon will use the mode_switcher
* method for 'n', the speed_switcher for 's', and the control_send method
* for 'c'. Additionally, the driver type name will be displayed before
* the '>' command prompt in the top line of the display.
*/
.driver = &PROTO_binary,
};
/*
* Helpers:
*
* bool monitor_control_send(unsigned char *buf, size_t len)
* Ship a packet payload to the device. Calls the driver send_control()
* method to add headers/trailers/checksum; also dumps the sent
* packet to the packet window, if the send_control() is playing
* nice by using session.msgbuf to assemble the message.
*
* void monitor_log(const char *fmt, ...)
* Write a message to the packet window. Safe if the packet window
* is not on screen.
*
* void monitor_complain(const char *fmt, ...)
* Post an error message to the command window, wait till user presses a key.
* You get to make sure the message will fit.
*
* void monitor_fixframe(WINDOW *win)
* Fix the frame of win to the right of the current location by redrawing
* ACS_VLINE there. Useful after doing wclrtoeol() and writing on the
* line.
*
* The libgpsd session object is accessible as the global variable 'session'.
*/
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