dump1090/net_io.c
2019-06-06 14:17:27 +08:00

2363 lines
81 KiB
C

// Part of dump1090, a Mode S message decoder for RTLSDR devices.
//
// net_io.c: network handling.
//
// Copyright (c) 2014-2016 Oliver Jowett <oliver@mutability.co.uk>
//
// This file is free software: you may copy, redistribute 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 file 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, see <http://www.gnu.org/licenses/>.
// This file incorporates work covered by the following copyright and
// permission notice:
//
// Copyright (C) 2012 by Salvatore Sanfilippo <antirez@gmail.com>
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "dump1090.h"
/* for PRIX64 */
#include <inttypes.h>
#include <assert.h>
#include <stdarg.h>
//
// ============================= Networking =============================
//
// Note: here we disregard any kind of good coding practice in favor of
// extreme simplicity, that is:
//
// 1) We only rely on the kernel buffers for our I/O without any kind of
// user space buffering.
// 2) We don't register any kind of event handler, from time to time a
// function gets called and we accept new connections. All the rest is
// handled via non-blocking I/O and manually polling clients to see if
// they have something new to share with us when reading is needed.
static int handleBeastCommand(struct client *c, char *p);
static int decodeBinMessage(struct client *c, char *p);
static int decodeHexMessage(struct client *c, char *hex);
static void send_raw_heartbeat(struct net_service *service);
static void send_beast_heartbeat(struct net_service *service);
static void send_sbs_heartbeat(struct net_service *service);
static void writeFATSVEvent(struct modesMessage *mm, struct aircraft *a);
static void writeFATSVPositionUpdate(float lat, float lon, float alt);
static void autoset_modeac();
//
//=========================================================================
//
// Networking "stack" initialization
//
// Init a service with the given read/write characteristics, return the new service.
// Doesn't arrange for the service to listen or connect
struct net_service *serviceInit(const char *descr, struct net_writer *writer, heartbeat_fn hb, read_mode_t mode, const char *sep, read_fn handler)
{
struct net_service *service;
if (!(service = calloc(sizeof(*service), 1))) {
fprintf(stderr, "Out of memory allocating service %s\n", descr);
exit(1);
}
service->next = Modes.services;
Modes.services = service;
service->descr = descr;
service->listener_count = 0;
service->connections = 0;
service->writer = writer;
service->read_sep = sep;
service->read_mode = mode;
service->read_handler = handler;
if (service->writer) {
if (! (service->writer->data = malloc(MODES_OUT_BUF_SIZE)) ) {
fprintf(stderr, "Out of memory allocating output buffer for service %s\n", descr);
exit(1);
}
service->writer->service = service;
service->writer->dataUsed = 0;
service->writer->lastWrite = mstime();
service->writer->send_heartbeat = hb;
}
return service;
}
// Create a client attached to the given service using the provided socket FD
struct client *createSocketClient(struct net_service *service, int fd)
{
anetSetSendBuffer(Modes.aneterr, fd, (MODES_NET_SNDBUF_SIZE << Modes.net_sndbuf_size));
return createGenericClient(service, fd);
}
// Create a client attached to the given service using the provided FD (might not be a socket!)
struct client *createGenericClient(struct net_service *service, int fd)
{
struct client *c;
anetNonBlock(Modes.aneterr, fd);
if (!(c = (struct client *) malloc(sizeof(*c)))) {
fprintf(stderr, "Out of memory allocating a new %s network client\n", service->descr);
exit(1);
}
c->service = service;
c->next = Modes.clients;
c->fd = fd;
c->buflen = 0;
c->modeac_requested = 0;
Modes.clients = c;
++service->connections;
if (service->writer && service->connections == 1) {
service->writer->lastWrite = mstime(); // suppress heartbeat initially
}
return c;
}
// Initiate an outgoing connection which will use the given service.
// Return the new client or NULL if the connection failed
struct client *serviceConnect(struct net_service *service, char *addr, int port)
{
int s;
char buf[20];
// Bleh.
snprintf(buf, 20, "%d", port);
s = anetTcpConnect(Modes.aneterr, addr, buf);
if (s == ANET_ERR)
return NULL;
return createSocketClient(service, s);
}
// Set up the given service to listen on an address/port.
// _exits_ on failure!
void serviceListen(struct net_service *service, char *bind_addr, char *bind_ports)
{
int *fds = NULL;
int n = 0;
char *p, *end;
char buf[128];
if (service->listener_count > 0) {
fprintf(stderr, "Tried to set up the service %s twice!\n", service->descr);
exit(1);
}
if (!bind_ports || !strcmp(bind_ports, "") || !strcmp(bind_ports, "0"))
return;
p = bind_ports;
while (p && *p) {
int newfds[16];
int nfds, i;
end = strpbrk(p, ", ");
if (!end) {
strncpy(buf, p, sizeof(buf));
buf[sizeof(buf)-1] = 0;
p = NULL;
} else {
size_t len = end - p;
if (len >= sizeof(buf))
len = sizeof(buf) - 1;
memcpy(buf, p, len);
buf[len] = 0;
p = end + 1;
}
nfds = anetTcpServer(Modes.aneterr, buf, bind_addr, newfds, sizeof(newfds));
if (nfds == ANET_ERR) {
fprintf(stderr, "Error opening the listening port %s (%s): %s\n",
buf, service->descr, Modes.aneterr);
exit(1);
}
fds = realloc(fds, (n+nfds) * sizeof(int));
if (!fds) {
fprintf(stderr, "out of memory\n");
exit(1);
}
for (i = 0; i < nfds; ++i) {
anetNonBlock(Modes.aneterr, newfds[i]);
fds[n++] = newfds[i];
}
}
service->listener_count = n;
service->listener_fds = fds;
}
struct net_service *makeBeastInputService(void)
{
return serviceInit("Beast TCP input", NULL, NULL, READ_MODE_BEAST, NULL, decodeBinMessage);
}
struct net_service *makeFatsvOutputService(void)
{
return serviceInit("FATSV TCP output", &Modes.fatsv_out, NULL, READ_MODE_IGNORE, NULL, NULL);
}
void modesInitNet(void) {
struct net_service *s;
signal(SIGPIPE, SIG_IGN);
Modes.clients = NULL;
Modes.services = NULL;
// set up listeners
s = serviceInit("Raw TCP output", &Modes.raw_out, send_raw_heartbeat, READ_MODE_IGNORE, NULL, NULL);
serviceListen(s, Modes.net_bind_address, Modes.net_output_raw_ports);
s = serviceInit("Beast TCP output", &Modes.beast_out, send_beast_heartbeat, READ_MODE_BEAST_COMMAND, NULL, handleBeastCommand);
serviceListen(s, Modes.net_bind_address, Modes.net_output_beast_ports);
s = serviceInit("Basestation TCP output", &Modes.sbs_out, send_sbs_heartbeat, READ_MODE_IGNORE, NULL, NULL);
serviceListen(s, Modes.net_bind_address, Modes.net_output_sbs_ports);
s = serviceInit("Raw TCP input", NULL, NULL, READ_MODE_ASCII, "\n", decodeHexMessage);
serviceListen(s, Modes.net_bind_address, Modes.net_input_raw_ports);
s = makeBeastInputService();
serviceListen(s, Modes.net_bind_address, Modes.net_input_beast_ports);
}
//
//=========================================================================
//
// This function gets called from time to time when the decoding thread is
// awakened by new data arriving. This usually happens a few times every second
//
static struct client * modesAcceptClients(void) {
int fd;
struct net_service *s;
for (s = Modes.services; s; s = s->next) {
int i;
for (i = 0; i < s->listener_count; ++i) {
while ((fd = anetTcpAccept(Modes.aneterr, s->listener_fds[i])) >= 0) {
createSocketClient(s, fd);
}
}
}
return Modes.clients;
}
//
//=========================================================================
//
// On error free the client, collect the structure, adjust maxfd if needed.
//
static void modesCloseClient(struct client *c) {
if (!c->service) {
fprintf(stderr, "warning: double close of net client\n");
return;
}
// Clean up, but defer removing from the list until modesNetCleanup().
// This is because there may be stackframes still pointing at this
// client (unpredictably: reading from client A may cause client B to
// be freed)
close(c->fd);
c->service->connections--;
// mark it as inactive and ready to be freed
c->fd = -1;
c->service = NULL;
c->modeac_requested = 0;
autoset_modeac();
}
//
//=========================================================================
//
// Send the write buffer for the specified writer to all connected clients
//
static void flushWrites(struct net_writer *writer) {
struct client *c;
for (c = Modes.clients; c; c = c->next) {
if (!c->service)
continue;
if (c->service == writer->service) {
#ifndef _WIN32
int nwritten = write(c->fd, writer->data, writer->dataUsed);
#else
int nwritten = send(c->fd, writer->data, writer->dataUsed, 0 );
#endif
if (nwritten != writer->dataUsed) {
modesCloseClient(c);
}
}
}
writer->dataUsed = 0;
writer->lastWrite = mstime();
}
// Prepare to write up to 'len' bytes to the given net_writer.
// Returns a pointer to write to, or NULL to skip this write.
static void *prepareWrite(struct net_writer *writer, int len) {
if (!writer ||
!writer->service ||
!writer->service->connections ||
!writer->data)
return NULL;
if (len > MODES_OUT_BUF_SIZE)
return NULL;
if (writer->dataUsed + len >= MODES_OUT_BUF_SIZE) {
// Flush now to free some space
flushWrites(writer);
}
return writer->data + writer->dataUsed;
}
// Complete a write previously begun by prepareWrite.
// endptr should point one byte past the last byte written
// to the buffer returned from prepareWrite.
static void completeWrite(struct net_writer *writer, void *endptr) {
writer->dataUsed = endptr - writer->data;
if (writer->dataUsed >= Modes.net_output_flush_size) {
flushWrites(writer);
}
}
//
//=========================================================================
//
// Write raw output in Beast Binary format with Timestamp to TCP clients
//
static void modesSendBeastOutput(struct modesMessage *mm) {
int msgLen = mm->msgbits / 8;
char *p = prepareWrite(&Modes.beast_out, 2 + 2 * (7 + msgLen));
char ch;
int j;
int sig;
unsigned char *msg = (Modes.net_verbatim ? mm->verbatim : mm->msg);
if (!p)
return;
*p++ = 0x1a;
if (msgLen == MODES_SHORT_MSG_BYTES)
{*p++ = '2';}
else if (msgLen == MODES_LONG_MSG_BYTES)
{*p++ = '3';}
else if (msgLen == MODEAC_MSG_BYTES)
{*p++ = '1';}
else
{return;}
/* timestamp, big-endian */
*p++ = (ch = (mm->timestampMsg >> 40));
if (0x1A == ch) {*p++ = ch; }
*p++ = (ch = (mm->timestampMsg >> 32));
if (0x1A == ch) {*p++ = ch; }
*p++ = (ch = (mm->timestampMsg >> 24));
if (0x1A == ch) {*p++ = ch; }
*p++ = (ch = (mm->timestampMsg >> 16));
if (0x1A == ch) {*p++ = ch; }
*p++ = (ch = (mm->timestampMsg >> 8));
if (0x1A == ch) {*p++ = ch; }
*p++ = (ch = (mm->timestampMsg));
if (0x1A == ch) {*p++ = ch; }
sig = round(sqrt(mm->signalLevel) * 255);
if (mm->signalLevel > 0 && sig < 1)
sig = 1;
if (sig > 255)
sig = 255;
*p++ = ch = (char)sig;
if (0x1A == ch) {*p++ = ch; }
for (j = 0; j < msgLen; j++) {
*p++ = (ch = msg[j]);
if (0x1A == ch) {*p++ = ch; }
}
completeWrite(&Modes.beast_out, p);
}
static void send_beast_heartbeat(struct net_service *service)
{
static char heartbeat_message[] = { 0x1a, '1', 0, 0, 0, 0, 0, 0, 0, 0, 0 };
char *data;
if (!service->writer)
return;
data = prepareWrite(service->writer, sizeof(heartbeat_message));
if (!data)
return;
memcpy(data, heartbeat_message, sizeof(heartbeat_message));
completeWrite(service->writer, data + sizeof(heartbeat_message));
}
//
//=========================================================================
//
// Write raw output to TCP clients
//
static void modesSendRawOutput(struct modesMessage *mm) {
int msgLen = mm->msgbits / 8;
char *p = prepareWrite(&Modes.raw_out, msgLen*2 + 15);
int j;
unsigned char *msg = (Modes.net_verbatim ? mm->verbatim : mm->msg);
if (!p)
return;
if (Modes.mlat && mm->timestampMsg) {
/* timestamp, big-endian */
sprintf(p, "@%012" PRIX64,
mm->timestampMsg);
p += 13;
} else
*p++ = '*';
for (j = 0; j < msgLen; j++) {
sprintf(p, "%02X", msg[j]);
p += 2;
}
*p++ = ';';
*p++ = '\n';
completeWrite(&Modes.raw_out, p);
}
static void send_raw_heartbeat(struct net_service *service)
{
static char *heartbeat_message = "*0000;\n";
char *data;
int len = strlen(heartbeat_message);
if (!service->writer)
return;
data = prepareWrite(service->writer, len);
if (!data)
return;
memcpy(data, heartbeat_message, len);
completeWrite(service->writer, data + len);
}
//
//=========================================================================
//
// Write SBS output to TCP clients
//
static void modesSendSBSOutput(struct modesMessage *mm, struct aircraft *a) {
char *p;
struct timespec now;
struct tm stTime_receive, stTime_now;
int msgType;
// For now, suppress non-ICAO addresses
if (mm->addr & MODES_NON_ICAO_ADDRESS)
return;
p = prepareWrite(&Modes.sbs_out, 200);
if (!p)
return;
//
// SBS BS style output checked against the following reference
// http://www.homepages.mcb.net/bones/SBS/Article/Barebones42_Socket_Data.htm - seems comprehensive
//
// Decide on the basic SBS Message Type
switch (mm->msgtype) {
case 4:
case 20:
msgType = 5;
break;
break;
case 5:
case 21:
msgType = 6;
break;
case 0:
case 16:
msgType = 7;
break;
case 11:
msgType = 8;
break;
case 17:
case 18:
if (mm->metype >= 1 && mm->metype <= 4) {
msgType = 1;
} else if (mm->metype >= 5 && mm->metype <= 8) {
msgType = 2;
} else if (mm->metype >= 9 && mm->metype <= 18) {
msgType = 3;
} else if (mm->metype == 19) {
msgType = 4;
} else {
return;
}
break;
default:
return;
}
// Fields 1 to 6 : SBS message type and ICAO address of the aircraft and some other stuff
p += sprintf(p, "MSG,%d,1,1,%06X,1,", msgType, mm->addr);
// Find current system time
clock_gettime(CLOCK_REALTIME, &now);
localtime_r(&now.tv_sec, &stTime_now);
// Find message reception time
time_t received = (time_t) (mm->sysTimestampMsg / 1000);
localtime_r(&received, &stTime_receive);
// Fields 7 & 8 are the message reception time and date
p += sprintf(p, "%04d/%02d/%02d,", (stTime_receive.tm_year+1900),(stTime_receive.tm_mon+1), stTime_receive.tm_mday);
p += sprintf(p, "%02d:%02d:%02d.%03u,", stTime_receive.tm_hour, stTime_receive.tm_min, stTime_receive.tm_sec, (unsigned) (mm->sysTimestampMsg % 1000));
// Fields 9 & 10 are the current time and date
p += sprintf(p, "%04d/%02d/%02d,", (stTime_now.tm_year+1900),(stTime_now.tm_mon+1), stTime_now.tm_mday);
p += sprintf(p, "%02d:%02d:%02d.%03u", stTime_now.tm_hour, stTime_now.tm_min, stTime_now.tm_sec, (unsigned) (now.tv_nsec / 1000000U));
// Field 11 is the callsign (if we have it)
if (mm->callsign_valid) {p += sprintf(p, ",%s", mm->callsign);}
else {p += sprintf(p, ",");}
// Field 12 is the altitude (if we have it)
if (Modes.use_gnss) {
if (mm->altitude_geom_valid) {
p += sprintf(p, ",%dH", mm->altitude_geom);
} else if (mm->altitude_baro_valid && trackDataValid(&a->geom_delta_valid)) {
p += sprintf(p, ",%dH", mm->altitude_baro + a->geom_delta);
} else if (mm->altitude_baro_valid) {
p += sprintf(p, ",%d", mm->altitude_baro);
} else {
p += sprintf(p, ",");
}
} else {
if (mm->altitude_baro_valid) {
p += sprintf(p, ",%d", mm->altitude_baro);
} else if (mm->altitude_geom_valid && trackDataValid(&a->geom_delta_valid)) {
p += sprintf(p, ",%d", mm->altitude_geom - a->geom_delta);
} else {
p += sprintf(p, ",");
}
}
// Field 13 is the ground Speed (if we have it)
if (mm->gs_valid) {
p += sprintf(p, ",%.0f", mm->gs.selected);
} else {
p += sprintf(p, ",");
}
// Field 14 is the ground Heading (if we have it)
if (mm->heading_valid && mm->heading_type == HEADING_GROUND_TRACK) {
p += sprintf(p, ",%.0f", mm->heading);
} else {
p += sprintf(p, ",");
}
// Fields 15 and 16 are the Lat/Lon (if we have it)
if (mm->cpr_decoded) {
p += sprintf(p, ",%1.5f,%1.5f", mm->decoded_lat, mm->decoded_lon);
} else {
p += sprintf(p, ",,");
}
// Field 17 is the VerticalRate (if we have it)
if (Modes.use_gnss) {
if (mm->geom_rate_valid) {
p += sprintf(p, ",%dH", mm->geom_rate);
} else if (mm->baro_rate_valid) {
p += sprintf(p, ",%d", mm->baro_rate);
} else {
p += sprintf(p, ",");
}
} else {
if (mm->baro_rate_valid) {
p += sprintf(p, ",%d", mm->baro_rate);
} else if (mm->geom_rate_valid) {
p += sprintf(p, ",%d", mm->geom_rate);
} else {
p += sprintf(p, ",");
}
}
// Field 18 is the Squawk (if we have it)
if (mm->squawk_valid) {
p += sprintf(p, ",%04x", mm->squawk);
} else {
p += sprintf(p, ",");
}
// Field 19 is the Squawk Changing Alert flag (if we have it)
if (mm->alert_valid) {
if (mm->alert) {
p += sprintf(p, ",-1");
} else {
p += sprintf(p, ",0");
}
} else {
p += sprintf(p, ",");
}
// Field 20 is the Squawk Emergency flag (if we have it)
if (mm->squawk_valid) {
if ((mm->squawk == 0x7500) || (mm->squawk == 0x7600) || (mm->squawk == 0x7700)) {
p += sprintf(p, ",-1");
} else {
p += sprintf(p, ",0");
}
} else {
p += sprintf(p, ",");
}
// Field 21 is the Squawk Ident flag (if we have it)
if (mm->spi_valid) {
if (mm->spi) {
p += sprintf(p, ",-1");
} else {
p += sprintf(p, ",0");
}
} else {
p += sprintf(p, ",");
}
// Field 22 is the OnTheGround flag (if we have it)
switch (mm->airground) {
case AG_GROUND:
p += sprintf(p, ",-1");
break;
case AG_AIRBORNE:
p += sprintf(p, ",0");
break;
default:
p += sprintf(p, ",");
break;
}
p += sprintf(p, "\r\n");
completeWrite(&Modes.sbs_out, p);
}
static void send_sbs_heartbeat(struct net_service *service)
{
static char *heartbeat_message = "\r\n"; // is there a better one?
char *data;
int len = strlen(heartbeat_message);
if (!service->writer)
return;
data = prepareWrite(service->writer, len);
if (!data)
return;
memcpy(data, heartbeat_message, len);
completeWrite(service->writer, data + len);
}
//
//=========================================================================
//
void modesQueueOutput(struct modesMessage *mm, struct aircraft *a) {
int is_mlat = (mm->source == SOURCE_MLAT);
if (a && !is_mlat && mm->correctedbits < 2) {
// Don't ever forward 2-bit-corrected messages via SBS output.
// Don't ever forward mlat messages via SBS output.
modesSendSBSOutput(mm, a);
}
if (!is_mlat && (Modes.net_verbatim || mm->correctedbits < 2)) {
// Forward 2-bit-corrected messages via raw output only if --net-verbatim is set
// Don't ever forward mlat messages via raw output.
modesSendRawOutput(mm);
}
if ((!is_mlat || Modes.forward_mlat) && (Modes.net_verbatim || mm->correctedbits < 2)) {
// Forward 2-bit-corrected messages via beast output only if --net-verbatim is set
// Forward mlat messages via beast output only if --forward-mlat is set
modesSendBeastOutput(mm);
}
if (a && !is_mlat) {
writeFATSVEvent(mm, a);
}
}
// Decode a little-endian IEEE754 float (binary32)
float ieee754_binary32_le_to_float(uint8_t *data)
{
double sign = (data[3] & 0x80) ? -1.0 : 1.0;
int16_t raw_exponent = ((data[3] & 0x7f) << 1) | ((data[2] & 0x80) >> 7);
uint32_t raw_significand = ((data[2] & 0x7f) << 16) | (data[1] << 8) | data[0];
if (raw_exponent == 0) {
if (raw_significand == 0) {
/* -0 is treated like +0 */
return 0;
} else {
/* denormal */
return ldexp(sign * raw_significand, -126 - 23);
}
}
if (raw_exponent == 255) {
if (raw_significand == 0) {
/* +/-infinity */
return sign < 0 ? -INFINITY : INFINITY;
} else {
/* NaN */
#ifdef NAN
return NAN;
#else
return 0.0f;
#endif
}
}
/* normalized value */
return ldexp(sign * ((1 << 23) | raw_significand), raw_exponent - 127 - 23);
}
static void handle_radarcape_position(float lat, float lon, float alt)
{
if (!isfinite(lat) || lat < -90 || lat > 90 || !isfinite(lon) || lon < -180 || lon > 180 || !isfinite(alt))
return;
writeFATSVPositionUpdate(lat, lon, alt);
if (!(Modes.bUserFlags & MODES_USER_LATLON_VALID)) {
Modes.fUserLat = lat;
Modes.fUserLon = lon;
Modes.bUserFlags |= MODES_USER_LATLON_VALID;
receiverPositionChanged(lat, lon, alt);
}
}
// recompute global Mode A/C setting
static void autoset_modeac() {
struct client *c;
if (!Modes.mode_ac_auto)
return;
Modes.mode_ac = 0;
for (c = Modes.clients; c; c = c->next) {
if (c->modeac_requested) {
Modes.mode_ac = 1;
break;
}
}
}
// Send some Beast settings commands to a client
void sendBeastSettings(struct client *c, const char *settings)
{
int len;
char *buf, *p;
len = strlen(settings) * 3;
buf = p = alloca(len);
while (*settings) {
*p++ = 0x1a;
*p++ = '1';
*p++ = *settings++;
}
anetWrite(c->fd, buf, len);
}
//
// Handle a Beast command message.
// Currently, we just look for the Mode A/C command message
// and ignore everything else.
//
static int handleBeastCommand(struct client *c, char *p) {
if (p[0] != '1') {
// huh?
return 0;
}
switch (p[1]) {
case 'j':
c->modeac_requested = 0;
break;
case 'J':
c->modeac_requested = 1;
break;
}
autoset_modeac();
return 0;
}
//
//=========================================================================
//
// This function decodes a Beast binary format message
//
// The message is passed to the higher level layers, so it feeds
// the selected screen output, the network output and so forth.
//
// If the message looks invalid it is silently discarded.
//
// The function always returns 0 (success) to the caller as there is no
// case where we want broken messages here to close the client connection.
//
static int decodeBinMessage(struct client *c, char *p) {
int msgLen = 0;
int j;
char ch;
unsigned char msg[MODES_LONG_MSG_BYTES + 7];
static struct modesMessage zeroMessage;
struct modesMessage mm;
MODES_NOTUSED(c);
memset(&mm, 0, sizeof(mm));
ch = *p++; /// Get the message type
if (ch == '1' && Modes.mode_ac) {
msgLen = MODEAC_MSG_BYTES;
} else if (ch == '2') {
msgLen = MODES_SHORT_MSG_BYTES;
} else if (ch == '3') {
msgLen = MODES_LONG_MSG_BYTES;
} else if (ch == '5') {
// Special case for Radarcape position messages.
float lat, lon, alt;
for (j = 0; j < 21; j++) { // and the data
msg[j] = ch = *p++;
if (0x1A == ch) {p++;}
}
lat = ieee754_binary32_le_to_float(msg + 4);
lon = ieee754_binary32_le_to_float(msg + 8);
alt = ieee754_binary32_le_to_float(msg + 12);
handle_radarcape_position(lat, lon, alt);
} else {
// Ignore this.
return 0;
}
if (msgLen) {
mm = zeroMessage;
// Mark messages received over the internet as remote so that we don't try to
// pass them off as being received by this instance when forwarding them
mm.remote = 1;
// Grab the timestamp (big endian format)
mm.timestampMsg = 0;
for (j = 0; j < 6; j++) {
ch = *p++;
mm.timestampMsg = mm.timestampMsg << 8 | (ch & 255);
if (0x1A == ch) {p++;}
}
// record reception time as the time we read it.
mm.sysTimestampMsg = mstime();
ch = *p++; // Grab the signal level
mm.signalLevel = ((unsigned char)ch / 255.0);
mm.signalLevel = mm.signalLevel * mm.signalLevel;
if (0x1A == ch) {p++;}
for (j = 0; j < msgLen; j++) { // and the data
msg[j] = ch = *p++;
if (0x1A == ch) {p++;}
}
if (msgLen == MODEAC_MSG_BYTES) { // ModeA or ModeC
Modes.stats_current.remote_received_modeac++;
decodeModeAMessage(&mm, ((msg[0] << 8) | msg[1]));
} else {
int result;
Modes.stats_current.remote_received_modes++;
result = decodeModesMessage(&mm, msg);
if (result < 0) {
if (result == -1)
Modes.stats_current.remote_rejected_unknown_icao++;
else
Modes.stats_current.remote_rejected_bad++;
return 0;
} else {
Modes.stats_current.remote_accepted[mm.correctedbits]++;
}
}
useModesMessage(&mm);
}
return (0);
}
//
//=========================================================================
//
// Turn an hex digit into its 4 bit decimal value.
// Returns -1 if the digit is not in the 0-F range.
//
static int hexDigitVal(int c) {
c = tolower(c);
if (c >= '0' && c <= '9') return c-'0';
else if (c >= 'a' && c <= 'f') return c-'a'+10;
else return -1;
}
//
//=========================================================================
//
// This function decodes a string representing message in raw hex format
// like: *8D4B969699155600E87406F5B69F; The string is null-terminated.
//
// The message is passed to the higher level layers, so it feeds
// the selected screen output, the network output and so forth.
//
// If the message looks invalid it is silently discarded.
//
// The function always returns 0 (success) to the caller as there is no
// case where we want broken messages here to close the client connection.
//
static int decodeHexMessage(struct client *c, char *hex) {
int l = strlen(hex), j;
unsigned char msg[MODES_LONG_MSG_BYTES];
struct modesMessage mm;
static struct modesMessage zeroMessage;
MODES_NOTUSED(c);
mm = zeroMessage;
// Mark messages received over the internet as remote so that we don't try to
// pass them off as being received by this instance when forwarding them
mm.remote = 1;
mm.signalLevel = 0;
// Remove spaces on the left and on the right
while(l && isspace(hex[l-1])) {
hex[l-1] = '\0'; l--;
}
while(isspace(*hex)) {
hex++; l--;
}
// Turn the message into binary.
// Accept *-AVR raw @-AVR/BEAST timeS+raw %-AVR timeS+raw (CRC good) <-BEAST timeS+sigL+raw
// and some AVR records that we can understand
if (hex[l-1] != ';') {return (0);} // not complete - abort
switch(hex[0]) {
case '<': {
mm.signalLevel = ((hexDigitVal(hex[13])<<4) | hexDigitVal(hex[14])) / 255.0;
mm.signalLevel = mm.signalLevel * mm.signalLevel;
hex += 15; l -= 16; // Skip <, timestamp and siglevel, and ;
break;}
case '@': // No CRC check
case '%': { // CRC is OK
hex += 13; l -= 14; // Skip @,%, and timestamp, and ;
break;}
case '*':
case ':': {
hex++; l-=2; // Skip * and ;
break;}
default: {
return (0); // We don't know what this is, so abort
break;}
}
if ( (l != (MODEAC_MSG_BYTES * 2))
&& (l != (MODES_SHORT_MSG_BYTES * 2))
&& (l != (MODES_LONG_MSG_BYTES * 2)) )
{return (0);} // Too short or long message... broken
if ( (0 == Modes.mode_ac)
&& (l == (MODEAC_MSG_BYTES * 2)) )
{return (0);} // Right length for ModeA/C, but not enabled
for (j = 0; j < l; j += 2) {
int high = hexDigitVal(hex[j]);
int low = hexDigitVal(hex[j+1]);
if (high == -1 || low == -1) return 0;
msg[j/2] = (high << 4) | low;
}
// record reception time as the time we read it.
mm.sysTimestampMsg = mstime();
if (l == (MODEAC_MSG_BYTES * 2)) { // ModeA or ModeC
Modes.stats_current.remote_received_modeac++;
decodeModeAMessage(&mm, ((msg[0] << 8) | msg[1]));
} else { // Assume ModeS
int result;
Modes.stats_current.remote_received_modes++;
result = decodeModesMessage(&mm, msg);
if (result < 0) {
if (result == -1)
Modes.stats_current.remote_rejected_unknown_icao++;
else
Modes.stats_current.remote_rejected_bad++;
return 0;
} else {
Modes.stats_current.remote_accepted[mm.correctedbits]++;
}
}
useModesMessage(&mm);
return (0);
}
__attribute__ ((format (printf,3,0))) static char *safe_vsnprintf(char *p, char *end, const char *format, va_list ap)
{
p += vsnprintf(p < end ? p : NULL, p < end ? (size_t)(end - p) : 0, format, ap);
return p;
}
__attribute__ ((format (printf,3,4))) static char *safe_snprintf(char *p, char *end, const char *format, ...)
{
va_list ap;
va_start(ap, format);
p += vsnprintf(p < end ? p : NULL, p < end ? (size_t)(end - p) : 0, format, ap);
va_end(ap);
return p;
}
//
//=========================================================================
//
// Return a description of planes in json. No metric conversion
//
// usual caveats about function-returning-pointer-to-static-buffer apply
static const char *jsonEscapeString(const char *str) {
static char buf[1024];
const char *in = str;
char *out = buf, *end = buf + sizeof(buf) - 10;
for (; *in && out < end; ++in) {
unsigned char ch = *in;
if (ch == '"' || ch == '\\') {
*out++ = '\\';
*out++ = ch;
} else if (ch < 32 || ch > 127) {
out = safe_snprintf(out, end, "\\u%04x", ch);
} else {
*out++ = ch;
}
}
*out++ = 0;
return buf;
}
static char *append_flags(char *p, char *end, struct aircraft *a, datasource_t source)
{
p = safe_snprintf(p, end, "[");
char *start = p;
if (a->callsign_valid.source == source)
p = safe_snprintf(p, end, "\"callsign\",");
if (a->altitude_baro_valid.source == source)
p = safe_snprintf(p, end, "\"altitude\",");
if (a->altitude_geom_valid.source == source)
p = safe_snprintf(p, end, "\"alt_geom\",");
if (a->gs_valid.source == source)
p = safe_snprintf(p, end, "\"gs\",");
if (a->ias_valid.source == source)
p = safe_snprintf(p, end, "\"ias\",");
if (a->tas_valid.source == source)
p = safe_snprintf(p, end, "\"tas\",");
if (a->mach_valid.source == source)
p = safe_snprintf(p, end, "\"mach\",");
if (a->track_valid.source == source)
p = safe_snprintf(p, end, "\"track\",");
if (a->track_rate_valid.source == source)
p = safe_snprintf(p, end, "\"track_rate\",");
if (a->roll_valid.source == source)
p = safe_snprintf(p, end, "\"roll\",");
if (a->mag_heading_valid.source == source)
p = safe_snprintf(p, end, "\"mag_heading\",");
if (a->true_heading_valid.source == source)
p = safe_snprintf(p, end, "\"true_heading\",");
if (a->baro_rate_valid.source == source)
p = safe_snprintf(p, end, "\"baro_rate\",");
if (a->geom_rate_valid.source == source)
p = safe_snprintf(p, end, "\"geom_rate\",");
if (a->squawk_valid.source == source)
p = safe_snprintf(p, end, "\"squawk\",");
if (a->emergency_valid.source == source)
p = safe_snprintf(p, end, "\"emergency\",");
if (a->nav_qnh_valid.source == source)
p = safe_snprintf(p, end, "\"nav_qnh\",");
if (a->nav_altitude_mcp_valid.source == source)
p = safe_snprintf(p, end, "\"nav_altitude_mcp\",");
if (a->nav_altitude_fms_valid.source == source)
p = safe_snprintf(p, end, "\"nav_altitude_fms\",");
if (a->nav_heading_valid.source == source)
p = safe_snprintf(p, end, "\"nav_heading\",");
if (a->nav_modes_valid.source == source)
p = safe_snprintf(p, end, "\"nav_modes\",");
if (a->position_valid.source == source)
p = safe_snprintf(p, end, "\"lat\",\"lon\",\"nic\",\"rc\",");
if (a->nic_baro_valid.source == source)
p = safe_snprintf(p, end, "\"nic_baro\",");
if (a->nac_p_valid.source == source)
p = safe_snprintf(p, end, "\"nac_p\",");
if (a->nac_v_valid.source == source)
p = safe_snprintf(p, end, "\"nac_v\",");
if (a->sil_valid.source == source)
p = safe_snprintf(p, end, "\"sil\",\"sil_type\",");
if (a->gva_valid.source == source)
p = safe_snprintf(p, end, "\"gva\",");
if (a->sda_valid.source == source)
p = safe_snprintf(p, end, "\"sda\",");
if (p != start)
--p;
p = safe_snprintf(p, end, "]");
return p;
}
static struct {
nav_modes_t flag;
const char *name;
} nav_modes_names[] = {
{ NAV_MODE_AUTOPILOT, "autopilot" },
{ NAV_MODE_VNAV, "vnav" },
{ NAV_MODE_ALT_HOLD, "althold" },
{ NAV_MODE_APPROACH, "approach" },
{ NAV_MODE_LNAV, "lnav" },
{ NAV_MODE_TCAS, "tcas" },
{ 0, NULL }
};
static char *append_nav_modes(char *p, char *end, nav_modes_t flags, const char *quote, const char *sep)
{
int first = 1;
for (int i = 0; nav_modes_names[i].name; ++i) {
if (!(flags & nav_modes_names[i].flag)) {
continue;
}
if (!first) {
p = safe_snprintf(p, end, "%s", sep);
}
first = 0;
p = safe_snprintf(p, end, "%s%s%s", quote, nav_modes_names[i].name, quote);
}
return p;
}
static const char *nav_modes_flags_string(nav_modes_t flags) {
static char buf[256];
buf[0] = 0;
append_nav_modes(buf, buf + sizeof(buf), flags, "", " ");
return buf;
}
static const char *addrtype_enum_string(addrtype_t type) {
switch (type) {
case ADDR_ADSB_ICAO:
return "adsb_icao";
case ADDR_ADSB_ICAO_NT:
return "adsb_icao_nt";
case ADDR_ADSR_ICAO:
return "adsr_icao";
case ADDR_TISB_ICAO:
return "tisb_icao";
case ADDR_ADSB_OTHER:
return "adsb_other";
case ADDR_ADSR_OTHER:
return "adsr_other";
case ADDR_TISB_OTHER:
return "tisb_other";
case ADDR_TISB_TRACKFILE:
return "tisb_trackfile";
default:
return "unknown";
}
}
static const char *emergency_enum_string(emergency_t emergency)
{
switch (emergency) {
case EMERGENCY_NONE: return "none";
case EMERGENCY_GENERAL: return "general";
case EMERGENCY_LIFEGUARD: return "lifeguard";
case EMERGENCY_MINFUEL: return "minfuel";
case EMERGENCY_NORDO: return "nordo";
case EMERGENCY_UNLAWFUL: return "unlawful";
case EMERGENCY_DOWNED: return "downed";
default: return "reserved";
}
}
static const char *sil_type_enum_string(sil_type_t type)
{
switch (type) {
case SIL_UNKNOWN: return "unknown";
case SIL_PER_HOUR: return "perhour";
case SIL_PER_SAMPLE: return "persample";
default: return "invalid";
}
}
static const char *nav_altitude_source_enum_string(nav_altitude_source_t src)
{
switch (src) {
case NAV_ALT_INVALID: return "invalid";
case NAV_ALT_UNKNOWN: return "unknown";
case NAV_ALT_AIRCRAFT: return "aircraft";
case NAV_ALT_MCP: return "mcp";
case NAV_ALT_FMS: return "fms";
default: return "invalid";
}
}
char *generateAircraftJson(const char *url_path, int *len) {
uint64_t now = mstime();
struct aircraft *a;
int buflen = 32768; // The initial buffer is resized as needed
char *buf = (char *) malloc(buflen), *p = buf, *end = buf+buflen;
char *line_start;
int first = 1;
MODES_NOTUSED(url_path);
_messageNow = now;
p = safe_snprintf(p, end,
"{ \"now\" : %.1f,\n"
" \"messages\" : %u,\n"
" \"aircraft\" : [",
now / 1000.0,
Modes.stats_current.messages_total + Modes.stats_alltime.messages_total);
for (a = Modes.aircrafts; a; a = a->next) {
if (a->messages < 2) { // basic filter for bad decodes
continue;
}
if (first)
first = 0;
else
*p++ = ',';
retry:
line_start = p;
p = safe_snprintf(p, end, "\n {\"hex\":\"%s%06x\"", (a->addr & MODES_NON_ICAO_ADDRESS) ? "~" : "", a->addr & 0xFFFFFF);
if (a->addrtype != ADDR_ADSB_ICAO)
p = safe_snprintf(p, end, ",\"type\":\"%s\"", addrtype_enum_string(a->addrtype));
if (trackDataValid(&a->callsign_valid))
p = safe_snprintf(p, end, ",\"flight\":\"%s\"", jsonEscapeString(a->callsign));
if (trackDataValid(&a->airground_valid) && a->airground_valid.source >= SOURCE_MODE_S_CHECKED && a->airground == AG_GROUND)
p = safe_snprintf(p, end, ",\"alt_baro\":\"ground\"");
else {
if (trackDataValid(&a->altitude_baro_valid))
p = safe_snprintf(p, end, ",\"alt_baro\":%d", a->altitude_baro);
if (trackDataValid(&a->altitude_geom_valid))
p = safe_snprintf(p, end, ",\"alt_geom\":%d", a->altitude_geom);
}
if (trackDataValid(&a->gs_valid))
p = safe_snprintf(p, end, ",\"gs\":%.1f", a->gs);
if (trackDataValid(&a->ias_valid))
p = safe_snprintf(p, end, ",\"ias\":%u", a->ias);
if (trackDataValid(&a->tas_valid))
p = safe_snprintf(p, end, ",\"tas\":%u", a->tas);
if (trackDataValid(&a->mach_valid))
p = safe_snprintf(p, end, ",\"mach\":%.3f", a->mach);
if (trackDataValid(&a->track_valid))
p = safe_snprintf(p, end, ",\"track\":%.1f", a->track);
if (trackDataValid(&a->track_rate_valid))
p = safe_snprintf(p, end, ",\"track_rate\":%.2f", a->track_rate);
if (trackDataValid(&a->roll_valid))
p = safe_snprintf(p, end, ",\"roll\":%.1f", a->roll);
if (trackDataValid(&a->mag_heading_valid))
p = safe_snprintf(p, end, ",\"mag_heading\":%.1f", a->mag_heading);
if (trackDataValid(&a->true_heading_valid))
p = safe_snprintf(p, end, ",\"true_heading\":%.1f", a->true_heading);
if (trackDataValid(&a->baro_rate_valid))
p = safe_snprintf(p, end, ",\"baro_rate\":%d", a->baro_rate);
if (trackDataValid(&a->geom_rate_valid))
p = safe_snprintf(p, end, ",\"geom_rate\":%d", a->geom_rate);
if (trackDataValid(&a->squawk_valid))
p = safe_snprintf(p, end, ",\"squawk\":\"%04x\"", a->squawk);
if (trackDataValid(&a->emergency_valid))
p = safe_snprintf(p, end, ",\"emergency\":\"%s\"", emergency_enum_string(a->emergency));
if (a->category != 0)
p = safe_snprintf(p, end, ",\"category\":\"%02X\"", a->category);
if (trackDataValid(&a->nav_qnh_valid))
p = safe_snprintf(p, end, ",\"nav_qnh\":%.1f", a->nav_qnh);
if (trackDataValid(&a->nav_altitude_mcp_valid))
p = safe_snprintf(p, end, ",\"nav_altitude_mcp\":%d", a->nav_altitude_mcp);
if (trackDataValid(&a->nav_altitude_fms_valid))
p = safe_snprintf(p, end, ",\"nav_altitude_fms\":%d", a->nav_altitude_fms);
if (trackDataValid(&a->nav_heading_valid))
p = safe_snprintf(p, end, ",\"nav_heading\":%.1f", a->nav_heading);
if (trackDataValid(&a->nav_modes_valid)) {
p = safe_snprintf(p, end, ",\"nav_modes\":[");
p = append_nav_modes(p, end, a->nav_modes, "\"", ",");
p = safe_snprintf(p, end, "]");
}
if (trackDataValid(&a->position_valid))
p = safe_snprintf(p, end, ",\"lat\":%f,\"lon\":%f,\"nic\":%u,\"rc\":%u,\"seen_pos\":%.1f", a->lat, a->lon, a->pos_nic, a->pos_rc, (now - a->position_valid.updated)/1000.0);
if (a->adsb_version >= 0)
p = safe_snprintf(p, end, ",\"version\":%d", a->adsb_version);
if (trackDataValid(&a->nic_baro_valid))
p = safe_snprintf(p, end, ",\"nic_baro\":%u", a->nic_baro);
if (trackDataValid(&a->nac_p_valid))
p = safe_snprintf(p, end, ",\"nac_p\":%u", a->nac_p);
if (trackDataValid(&a->nac_v_valid))
p = safe_snprintf(p, end, ",\"nac_v\":%u", a->nac_v);
if (trackDataValid(&a->sil_valid))
p = safe_snprintf(p, end, ",\"sil\":%u", a->sil);
if (a->sil_type != SIL_INVALID)
p = safe_snprintf(p, end, ",\"sil_type\":\"%s\"", sil_type_enum_string(a->sil_type));
if (trackDataValid(&a->gva_valid))
p = safe_snprintf(p, end, ",\"gva\":%u", a->gva);
if (trackDataValid(&a->sda_valid))
p = safe_snprintf(p, end, ",\"sda\":%u", a->sda);
p = safe_snprintf(p, end, ",\"mlat\":");
p = append_flags(p, end, a, SOURCE_MLAT);
p = safe_snprintf(p, end, ",\"tisb\":");
p = append_flags(p, end, a, SOURCE_TISB);
p = safe_snprintf(p, end, ",\"messages\":%ld,\"seen\":%.1f,\"rssi\":%.1f}",
a->messages, (now - a->seen)/1000.0,
10 * log10((a->signalLevel[0] + a->signalLevel[1] + a->signalLevel[2] + a->signalLevel[3] +
a->signalLevel[4] + a->signalLevel[5] + a->signalLevel[6] + a->signalLevel[7] + 1e-5) / 8));
if ((p + 10) >= end) { // +10 to leave some space for the final line
// overran the buffer
int used = line_start - buf;
buflen *= 2;
buf = (char *) realloc(buf, buflen);
p = buf+used;
end = buf + buflen;
goto retry;
}
}
p = safe_snprintf(p, end, "\n ]\n}\n");
*len = p-buf;
return buf;
}
static char * appendStatsJson(char *p,
char *end,
struct stats *st,
const char *key)
{
int i;
p = safe_snprintf(p, end,
"\"%s\":{\"start\":%.1f,\"end\":%.1f",
key,
st->start / 1000.0,
st->end / 1000.0);
if (!Modes.net_only) {
p = safe_snprintf(p, end,
",\"local\":{\"samples_processed\":%llu"
",\"samples_dropped\":%llu"
",\"modeac\":%u"
",\"modes\":%u"
",\"bad\":%u"
",\"unknown_icao\":%u",
(unsigned long long)st->samples_processed,
(unsigned long long)st->samples_dropped,
st->demod_modeac,
st->demod_preambles,
st->demod_rejected_bad,
st->demod_rejected_unknown_icao);
for (i=0; i <= Modes.nfix_crc; ++i) {
if (i == 0) p = safe_snprintf(p, end, ",\"accepted\":[%u", st->demod_accepted[i]);
else p = safe_snprintf(p, end, ",%u", st->demod_accepted[i]);
}
p = safe_snprintf(p, end, "]");
if (st->signal_power_sum > 0 && st->signal_power_count > 0)
p = safe_snprintf(p, end, ",\"signal\":%.1f", 10 * log10(st->signal_power_sum / st->signal_power_count));
if (st->noise_power_sum > 0 && st->noise_power_count > 0)
p = safe_snprintf(p, end, ",\"noise\":%.1f", 10 * log10(st->noise_power_sum / st->noise_power_count));
if (st->peak_signal_power > 0)
p = safe_snprintf(p, end, ",\"peak_signal\":%.1f", 10 * log10(st->peak_signal_power));
p = safe_snprintf(p, end, ",\"strong_signals\":%d}", st->strong_signal_count);
}
if (Modes.net) {
p = safe_snprintf(p, end,
",\"remote\":{\"modeac\":%u"
",\"modes\":%u"
",\"bad\":%u"
",\"unknown_icao\":%u",
st->remote_received_modeac,
st->remote_received_modes,
st->remote_rejected_bad,
st->remote_rejected_unknown_icao);
for (i=0; i <= Modes.nfix_crc; ++i) {
if (i == 0) p = safe_snprintf(p, end, ",\"accepted\":[%u", st->remote_accepted[i]);
else p = safe_snprintf(p, end, ",%u", st->remote_accepted[i]);
}
p = safe_snprintf(p, end, "]}");
}
{
uint64_t demod_cpu_millis = (uint64_t)st->demod_cpu.tv_sec*1000UL + st->demod_cpu.tv_nsec/1000000UL;
uint64_t reader_cpu_millis = (uint64_t)st->reader_cpu.tv_sec*1000UL + st->reader_cpu.tv_nsec/1000000UL;
uint64_t background_cpu_millis = (uint64_t)st->background_cpu.tv_sec*1000UL + st->background_cpu.tv_nsec/1000000UL;
p = safe_snprintf(p, end,
",\"cpr\":{\"surface\":%u"
",\"airborne\":%u"
",\"global_ok\":%u"
",\"global_bad\":%u"
",\"global_range\":%u"
",\"global_speed\":%u"
",\"global_skipped\":%u"
",\"local_ok\":%u"
",\"local_aircraft_relative\":%u"
",\"local_receiver_relative\":%u"
",\"local_skipped\":%u"
",\"local_range\":%u"
",\"local_speed\":%u"
",\"filtered\":%u}"
",\"altitude_suppressed\":%u"
",\"cpu\":{\"demod\":%llu,\"reader\":%llu,\"background\":%llu}"
",\"tracks\":{\"all\":%u"
",\"single_message\":%u}"
",\"messages\":%u}",
st->cpr_surface,
st->cpr_airborne,
st->cpr_global_ok,
st->cpr_global_bad,
st->cpr_global_range_checks,
st->cpr_global_speed_checks,
st->cpr_global_skipped,
st->cpr_local_ok,
st->cpr_local_aircraft_relative,
st->cpr_local_receiver_relative,
st->cpr_local_skipped,
st->cpr_local_range_checks,
st->cpr_local_speed_checks,
st->cpr_filtered,
st->suppressed_altitude_messages,
(unsigned long long)demod_cpu_millis,
(unsigned long long)reader_cpu_millis,
(unsigned long long)background_cpu_millis,
st->unique_aircraft,
st->single_message_aircraft,
st->messages_total);
}
return p;
}
char *generateStatsJson(const char *url_path, int *len) {
struct stats add;
char *buf = (char *) malloc(4096), *p = buf, *end = buf + 4096;
MODES_NOTUSED(url_path);
p = safe_snprintf(p, end, "{\n");
p = appendStatsJson(p, end, &Modes.stats_current, "latest");
p = safe_snprintf(p, end, ",\n");
p = appendStatsJson(p, end, &Modes.stats_1min[Modes.stats_latest_1min], "last1min");
p = safe_snprintf(p, end, ",\n");
p = appendStatsJson(p, end, &Modes.stats_5min, "last5min");
p = safe_snprintf(p, end, ",\n");
p = appendStatsJson(p, end, &Modes.stats_15min, "last15min");
p = safe_snprintf(p, end, ",\n");
add_stats(&Modes.stats_alltime, &Modes.stats_current, &add);
p = appendStatsJson(p, end, &add, "total");
p = safe_snprintf(p, end, "\n}\n");
assert(p < end);
*len = p-buf;
return buf;
}
//
// Return a description of the receiver in json.
//
char *generateReceiverJson(const char *url_path, int *len)
{
char *buf = (char *) malloc(1024), *p = buf;
int history_size;
MODES_NOTUSED(url_path);
// work out number of valid history entries
if (Modes.json_aircraft_history[HISTORY_SIZE-1].content == NULL)
history_size = Modes.json_aircraft_history_next;
else
history_size = HISTORY_SIZE;
p += sprintf(p, "{ " \
"\"version\" : \"%s\", "
"\"refresh\" : %.0f, "
"\"history\" : %d",
MODES_DUMP1090_VERSION, 1.0*Modes.json_interval, history_size);
if (Modes.json_location_accuracy && (Modes.fUserLat != 0.0 || Modes.fUserLon != 0.0)) {
if (Modes.json_location_accuracy == 1) {
p += sprintf(p, ", " \
"\"lat\" : %.2f, "
"\"lon\" : %.2f",
Modes.fUserLat, Modes.fUserLon); // round to 2dp - about 0.5-1km accuracy - for privacy reasons
} else {
p += sprintf(p, ", " \
"\"lat\" : %.6f, "
"\"lon\" : %.6f",
Modes.fUserLat, Modes.fUserLon); // exact location
}
}
p += sprintf(p, " }\n");
*len = (p - buf);
return buf;
}
char *generateHistoryJson(const char *url_path, int *len)
{
int history_index = -1;
if (sscanf(url_path, "/data/history_%d.json", &history_index) != 1)
return NULL;
if (history_index < 0 || history_index >= HISTORY_SIZE)
return NULL;
if (!Modes.json_aircraft_history[history_index].content)
return NULL;
*len = Modes.json_aircraft_history[history_index].clen;
return strdup(Modes.json_aircraft_history[history_index].content);
}
// Write JSON to file
void writeJsonToFile(const char *file, char * (*generator) (const char *,int*))
{
#ifndef _WIN32
char pathbuf[PATH_MAX];
char tmppath[PATH_MAX];
int fd;
int len = 0;
mode_t mask;
char *content;
if (!Modes.json_dir)
return;
snprintf(tmppath, PATH_MAX, "%s/%s.XXXXXX", Modes.json_dir, file);
tmppath[PATH_MAX-1] = 0;
fd = mkstemp(tmppath);
if (fd < 0)
return;
mask = umask(0);
umask(mask);
fchmod(fd, 0644 & ~mask);
snprintf(pathbuf, PATH_MAX, "/data/%s", file);
pathbuf[PATH_MAX-1] = 0;
content = generator(pathbuf, &len);
if (write(fd, content, len) != len)
goto error_1;
if (close(fd) < 0)
goto error_2;
snprintf(pathbuf, PATH_MAX, "%s/%s", Modes.json_dir, file);
pathbuf[PATH_MAX-1] = 0;
rename(tmppath, pathbuf);
free(content);
return;
error_1:
close(fd);
error_2:
unlink(tmppath);
free(content);
return;
#endif
}
//
//=========================================================================
//
// This function polls the clients using read() in order to receive new
// messages from the net.
//
// The message is supposed to be separated from the next message by the
// separator 'sep', which is a null-terminated C string.
//
// Every full message received is decoded and passed to the higher layers
// calling the function's 'handler'.
//
// The handler returns 0 on success, or 1 to signal this function we should
// close the connection with the client in case of non-recoverable errors.
//
static void modesReadFromClient(struct client *c) {
int left;
int nread;
int bContinue = 1;
while (bContinue) {
left = MODES_CLIENT_BUF_SIZE - c->buflen - 1; // leave 1 extra byte for NUL termination in the ASCII case
// If our buffer is full discard it, this is some badly formatted shit
if (left <= 0) {
c->buflen = 0;
left = MODES_CLIENT_BUF_SIZE;
// If there is garbage, read more to discard it ASAP
}
#ifndef _WIN32
nread = read(c->fd, c->buf+c->buflen, left);
#else
nread = recv(c->fd, c->buf+c->buflen, left, 0);
if (nread < 0) {errno = WSAGetLastError();}
#endif
// If we didn't get all the data we asked for, then return once we've processed what we did get.
if (nread != left) {
bContinue = 0;
}
if (nread == 0) { // End of file
modesCloseClient(c);
return;
}
#ifndef _WIN32
if (nread < 0 && (errno == EAGAIN || errno == EWOULDBLOCK)) // No data available (not really an error)
#else
if (nread < 0 && errno == EWOULDBLOCK) // No data available (not really an error)
#endif
{
return;
}
if (nread < 0) { // Other errors
modesCloseClient(c);
return;
}
c->buflen += nread;
char *som = c->buf; // first byte of next message
char *eod = som + c->buflen; // one byte past end of data
char *p;
switch (c->service->read_mode) {
case READ_MODE_IGNORE:
// drop the bytes on the floor
som = eod;
break;
case READ_MODE_BEAST:
// This is the Beast Binary scanning case.
// If there is a complete message still in the buffer, there must be the separator 'sep'
// in the buffer, note that we full-scan the buffer at every read for simplicity.
while (som < eod && ((p = memchr(som, (char) 0x1a, eod - som)) != NULL)) { // The first byte of buffer 'should' be 0x1a
som = p; // consume garbage up to the 0x1a
++p; // skip 0x1a
if (p >= eod) {
// Incomplete message in buffer, retry later
break;
}
char *eom; // one byte past end of message
if (*p == '1') {
eom = p + MODEAC_MSG_BYTES + 8; // point past remainder of message
} else if (*p == '2') {
eom = p + MODES_SHORT_MSG_BYTES + 8;
} else if (*p == '3') {
eom = p + MODES_LONG_MSG_BYTES + 8;
} else if (*p == '4') {
eom = p + MODES_LONG_MSG_BYTES + 8;
} else if (*p == '5') {
eom = p + MODES_LONG_MSG_BYTES + 8;
} else {
// Not a valid beast message, skip 0x1a and try again
++som;
continue;
}
// we need to be careful of double escape characters in the message body
for (p = som + 1; p < eod && p < eom; p++) {
if (0x1A == *p) {
p++;
eom++;
}
}
if (eom > eod) { // Incomplete message in buffer, retry later
break;
}
// Have a 0x1a followed by 1/2/3/4/5 - pass message to handler.
if (c->service->read_handler(c, som + 1)) {
modesCloseClient(c);
return;
}
// advance to next message
som = eom;
}
break;
case READ_MODE_BEAST_COMMAND:
while (som < eod && ((p = memchr(som, (char) 0x1a, eod - som)) != NULL)) { // The first byte of buffer 'should' be 0x1a
char *eom; // one byte past end of message
som = p; // consume garbage up to the 0x1a
++p; // skip 0x1a
if (p >= eod) {
// Incomplete message in buffer, retry later
break;
}
if (*p == '1') {
eom = p + 2;
} else {
// Not a valid beast command, skip 0x1a and try again
++som;
continue;
}
// we need to be careful of double escape characters in the message body
for (p = som + 1; p < eod && p < eom; p++) {
if (0x1A == *p) {
p++;
eom++;
}
}
if (eom > eod) { // Incomplete message in buffer, retry later
break;
}
// Have a 0x1a followed by 1 - pass message to handler.
if (c->service->read_handler(c, som + 1)) {
modesCloseClient(c);
return;
}
// advance to next message
som = eom;
}
break;
case READ_MODE_ASCII:
//
// This is the ASCII scanning case, AVR RAW or HTTP at present
// If there is a complete message still in the buffer, there must be the separator 'sep'
// in the buffer, note that we full-scan the buffer at every read for simplicity.
// Always NUL-terminate so we are free to use strstr()
// nb: we never fill the last byte of the buffer with read data (see above) so this is safe
*eod = '\0';
while (som < eod && (p = strstr(som, c->service->read_sep)) != NULL) { // end of first message if found
*p = '\0'; // The handler expects null terminated strings
if (c->service->read_handler(c, som)) { // Pass message to handler.
modesCloseClient(c); // Handler returns 1 on error to signal we .
return; // should close the client connection
}
som = p + strlen(c->service->read_sep); // Move to start of next message
}
break;
}
if (som > c->buf) { // We processed something - so
c->buflen = eod - som; // Update the unprocessed buffer length
memmove(c->buf, som, c->buflen); // Move what's remaining to the start of the buffer
} else { // If no message was decoded process the next client
return;
}
}
}
__attribute__ ((format (printf,4,5))) static char *appendFATSV(char *p, char *end, const char *field, const char *format, ...)
{
va_list ap;
va_start(ap, format);
p = safe_snprintf(p, end, "%s\t", field);
p = safe_vsnprintf(p, end, format, ap);
p = safe_snprintf(p, end, "\t");
va_end(ap);
return p;
}
#define TSV_MAX_PACKET_SIZE 800
#define TSV_VERSION "6E"
static void writeFATSVPositionUpdate(float lat, float lon, float alt)
{
static float last_lat, last_lon, last_alt;
if (lat == last_lat && lon == last_lon && alt == last_alt)
return;
last_lat = lat;
last_lon = lon;
last_alt = alt;
char *p = prepareWrite(&Modes.fatsv_out, TSV_MAX_PACKET_SIZE);
if (!p)
return;
char *end = p + TSV_MAX_PACKET_SIZE;
p = appendFATSV(p, end, "_v", "%s", TSV_VERSION);
p = appendFATSV(p, end, "clock", "%" PRIu64, messageNow() / 1000);
p = appendFATSV(p, end, "type", "%s", "location_update");
p = appendFATSV(p, end, "lat", "%.5f", lat);
p = appendFATSV(p, end, "lon", "%.5f", lon);
p = appendFATSV(p, end, "alt", "%.0f", alt);
p = appendFATSV(p, end, "altref", "%s", "egm96_meters");
--p; // remove last tab
p = safe_snprintf(p, end, "\n");
if (p < end)
completeWrite(&Modes.fatsv_out, p);
else
fprintf(stderr, "fatsv: output too large (max %d, overran by %d)\n", TSV_MAX_PACKET_SIZE, (int) (p - end));
}
static void writeFATSVEventMessage(struct modesMessage *mm, const char *datafield, unsigned char *data, size_t len)
{
char *p = prepareWrite(&Modes.fatsv_out, TSV_MAX_PACKET_SIZE);
if (!p)
return;
char *end = p + TSV_MAX_PACKET_SIZE;
p = appendFATSV(p, end, "_v", "%s", TSV_VERSION);
p = appendFATSV(p, end, "clock", "%" PRIu64, messageNow() / 1000);
p = appendFATSV(p, end, (mm->addr & MODES_NON_ICAO_ADDRESS) ? "otherid" : "hexid", "%06X", mm->addr & 0xFFFFFF);
if (mm->addrtype != ADDR_ADSB_ICAO) {
p = appendFATSV(p, end, "addrtype", "%s", addrtype_enum_string(mm->addrtype));
}
p = safe_snprintf(p, end, "%s\t", datafield);
for (size_t i = 0; i < len; ++i) {
p = safe_snprintf(p, end, "%02X", data[i]);
}
p = safe_snprintf(p, end, "\n");
if (p < end)
completeWrite(&Modes.fatsv_out, p);
else
fprintf(stderr, "fatsv: output too large (max %d, overran by %d)\n", TSV_MAX_PACKET_SIZE, (int) (p - end));
# undef bufsize
}
static void writeFATSVEvent(struct modesMessage *mm, struct aircraft *a)
{
// Write event records for a couple of message types.
if (!Modes.fatsv_out.service || !Modes.fatsv_out.service->connections) {
return; // not enabled or no active connections
}
if (a->messages < 2) // basic filter for bad decodes
return;
switch (mm->msgtype) {
case 20:
case 21:
// DF 20/21: Comm-B: emit if they've changed since we last sent them
switch (mm->commb_format) {
case COMMB_DATALINK_CAPS:
// BDS 1,0: data link capability report
if (memcmp(mm->MB, a->fatsv_emitted_bds_10, 7) != 0) {
memcpy(a->fatsv_emitted_bds_10, mm->MB, 7);
writeFATSVEventMessage(mm, "datalink_caps", mm->MB, 7);
}
break;
case COMMB_ACAS_RA:
// BDS 3,0: ACAS RA report
if (memcmp(mm->MB, a->fatsv_emitted_bds_30, 7) != 0) {
memcpy(a->fatsv_emitted_bds_30, mm->MB, 7);
writeFATSVEventMessage(mm, "commb_acas_ra", mm->MB, 7);
}
break;
default:
// nothing
break;
}
break;
case 17:
case 18:
// DF 17/18: extended squitter
if (mm->metype == 28 && mm->mesub == 2 && memcmp(mm->ME, &a->fatsv_emitted_es_acas_ra, 7) != 0) {
// type 28 subtype 2: ACAS RA report
// first byte has the type/subtype, remaining bytes match the BDS 3,0 format
memcpy(a->fatsv_emitted_es_acas_ra, mm->ME, 7);
writeFATSVEventMessage(mm, "es_acas_ra", mm->ME, 7);
} else if (mm->metype == 31 && (mm->mesub == 0 || mm->mesub == 1) && memcmp(mm->ME, a->fatsv_emitted_es_status, 7) != 0) {
// aircraft operational status
memcpy(a->fatsv_emitted_es_status, mm->ME, 7);
writeFATSVEventMessage(mm, "es_op_status", mm->ME, 7);
}
break;
}
}
static inline unsigned unsigned_difference(unsigned v1, unsigned v2)
{
return (v1 > v2) ? (v1 - v2) : (v2 - v1);
}
static inline float heading_difference(float h1, float h2)
{
float d = fabs(h1 - h2);
return (d < 180) ? d : (360 - d);
}
__attribute__ ((format (printf,6,7))) static char *appendFATSVMeta(char *p, char *end, const char *field, struct aircraft *a, const data_validity *source, const char *format, ...)
{
const char *sourcetype;
switch (source->source) {
case SOURCE_MODE_S:
sourcetype = "U";
break;
case SOURCE_MODE_S_CHECKED:
sourcetype = "S";
break;
case SOURCE_TISB:
sourcetype = "T";
break;
case SOURCE_ADSB:
sourcetype = "A";
break;
default:
// don't want to forward data sourced from these
return p;
}
if (!trackDataValid(source)) {
// expired data
return p;
}
if (source->updated > messageNow()) {
// data in the future
return p;
}
if (source->updated < a->fatsv_last_emitted) {
// not updated since last time
return p;
}
uint64_t age = (messageNow() - source->updated) / 1000;
if (age > 255) {
// too old
return p;
}
p = safe_snprintf(p, end, "%s\t", field);
va_list ap;
va_start(ap, format);
p = safe_vsnprintf(p, end, format, ap);
va_end(ap);
p = safe_snprintf(p, end, " %" PRIu64 " %s\t", age, sourcetype);
return p;
}
static const char *airground_enum_string(airground_t ag)
{
switch (ag) {
case AG_AIRBORNE:
return "A+";
case AG_GROUND:
return "G+";
default:
return "?";
}
}
static void writeFATSV()
{
struct aircraft *a;
static uint64_t next_update;
if (!Modes.fatsv_out.service || !Modes.fatsv_out.service->connections) {
return; // not enabled or no active connections
}
uint64_t now = mstime();
if (now < next_update) {
return;
}
// scan once a second at most
next_update = now + 1000;
for (a = Modes.aircrafts; a; a = a->next) {
if (a->messages < 2) // basic filter for bad decodes
continue;
// don't emit if it hasn't updated since last time
if (a->seen < a->fatsv_last_emitted) {
continue;
}
// Pretend we are "processing a message" so the validity checks work as expected
_messageNow = a->seen;
// some special cases:
int altValid = trackDataValid(&a->altitude_baro_valid);
int airgroundValid = trackDataValid(&a->airground_valid) && a->airground_valid.source >= SOURCE_MODE_S_CHECKED; // for non-ADS-B transponders, only trust DF11 CA field
int gsValid = trackDataValid(&a->gs_valid);
int squawkValid = trackDataValid(&a->squawk_valid);
int callsignValid = trackDataValid(&a->callsign_valid) && strcmp(a->callsign, " ") != 0;
int positionValid = trackDataValid(&a->position_valid);
// If we are definitely on the ground, suppress any unreliable altitude info.
// When on the ground, ADS-B transponders don't emit an ADS-B message that includes
// altitude, so a corrupted Mode S altitude response from some other in-the-air AC
// might be taken as the "best available altitude" and produce e.g. "airGround G+ alt 31000".
if (airgroundValid && a->airground == AG_GROUND && a->altitude_baro_valid.source < SOURCE_MODE_S_CHECKED)
altValid = 0;
// if it hasn't changed altitude, heading, or speed much,
// don't update so often
int changed =
(altValid && abs(a->altitude_baro - a->fatsv_emitted_altitude_baro) >= 50) ||
(trackDataValid(&a->altitude_geom_valid) && abs(a->altitude_geom - a->fatsv_emitted_altitude_geom) >= 50) ||
(trackDataValid(&a->baro_rate_valid) && abs(a->baro_rate - a->fatsv_emitted_baro_rate) > 500) ||
(trackDataValid(&a->geom_rate_valid) && abs(a->geom_rate - a->fatsv_emitted_geom_rate) > 500) ||
(trackDataValid(&a->track_valid) && heading_difference(a->track, a->fatsv_emitted_track) >= 2) ||
(trackDataValid(&a->track_rate_valid) && fabs(a->track_rate - a->fatsv_emitted_track_rate) >= 0.5) ||
(trackDataValid(&a->roll_valid) && fabs(a->roll - a->fatsv_emitted_roll) >= 5.0) ||
(trackDataValid(&a->mag_heading_valid) && heading_difference(a->mag_heading, a->fatsv_emitted_mag_heading) >= 2) ||
(trackDataValid(&a->true_heading_valid) && heading_difference(a->true_heading, a->fatsv_emitted_true_heading) >= 2) ||
(gsValid && fabs(a->gs - a->fatsv_emitted_gs) >= 25) ||
(trackDataValid(&a->ias_valid) && unsigned_difference(a->ias, a->fatsv_emitted_ias) >= 25) ||
(trackDataValid(&a->tas_valid) && unsigned_difference(a->tas, a->fatsv_emitted_tas) >= 25) ||
(trackDataValid(&a->mach_valid) && fabs(a->mach - a->fatsv_emitted_mach) >= 0.02);
int immediate =
(trackDataValid(&a->nav_altitude_mcp_valid) && unsigned_difference(a->nav_altitude_mcp, a->fatsv_emitted_nav_altitude_mcp) > 50) ||
(trackDataValid(&a->nav_altitude_fms_valid) && unsigned_difference(a->nav_altitude_fms, a->fatsv_emitted_nav_altitude_fms) > 50) ||
(trackDataValid(&a->nav_altitude_src_valid) && a->nav_altitude_src != a->fatsv_emitted_nav_altitude_src) ||
(trackDataValid(&a->nav_heading_valid) && heading_difference(a->nav_heading, a->fatsv_emitted_nav_heading) > 2) ||
(trackDataValid(&a->nav_modes_valid) && a->nav_modes != a->fatsv_emitted_nav_modes) ||
(trackDataValid(&a->nav_qnh_valid) && fabs(a->nav_qnh - a->fatsv_emitted_nav_qnh) > 0.8) || // 0.8 is the ES message resolution
(callsignValid && strcmp(a->callsign, a->fatsv_emitted_callsign) != 0) ||
(airgroundValid && a->airground == AG_AIRBORNE && a->fatsv_emitted_airground == AG_GROUND) ||
(airgroundValid && a->airground == AG_GROUND && a->fatsv_emitted_airground == AG_AIRBORNE) ||
(squawkValid && a->squawk != a->fatsv_emitted_squawk) ||
(trackDataValid(&a->emergency_valid) && a->emergency != a->fatsv_emitted_emergency);
uint64_t minAge;
if (immediate) {
// a change we want to emit right away
minAge = 0;
} else if (!positionValid) {
// don't send mode S very often
minAge = 30000;
} else if ((airgroundValid && a->airground == AG_GROUND) ||
(altValid && a->altitude_baro < 500 && (!gsValid || a->gs < 200)) ||
(gsValid && a->gs < 100 && (!altValid || a->altitude_baro < 1000))) {
// we are probably on the ground, increase the update rate
minAge = 1000;
} else if (!altValid || a->altitude_baro < 10000) {
// Below 10000 feet, emit up to every 5s when changing, 10s otherwise
minAge = (changed ? 5000 : 10000);
} else {
// Above 10000 feet, emit up to every 10s when changing, 30s otherwise
minAge = (changed ? 10000 : 30000);
}
if ((now - a->fatsv_last_emitted) < minAge)
continue;
char *p = prepareWrite(&Modes.fatsv_out, TSV_MAX_PACKET_SIZE);
if (!p)
return;
char *end = p + TSV_MAX_PACKET_SIZE;
p = appendFATSV(p, end, "_v", "%s", TSV_VERSION);
p = appendFATSV(p, end, "clock", "%" PRIu64, messageNow() / 1000);
p = appendFATSV(p, end, (a->addr & MODES_NON_ICAO_ADDRESS) ? "otherid" : "hexid", "%06X", a->addr & 0xFFFFFF);
// for fields we only emit on change,
// occasionally re-emit them all
int forceEmit = (now - a->fatsv_last_force_emit) > 600000;
// these don't change often / at all, only emit when they change
if (forceEmit || a->addrtype != a->fatsv_emitted_addrtype) {
p = appendFATSV(p, end, "addrtype", "%s", addrtype_enum_string(a->addrtype));
}
if (forceEmit || a->adsb_version != a->fatsv_emitted_adsb_version) {
p = appendFATSV(p, end, "adsb_version", "%d", a->adsb_version);
}
if (forceEmit || a->category != a->fatsv_emitted_category) {
p = appendFATSV(p, end, "category", "%02X", a->category);
}
if (trackDataValid(&a->nac_p_valid) && (forceEmit || a->nac_p != a->fatsv_emitted_nac_p)) {
p = appendFATSVMeta(p, end, "nac_p", a, &a->nac_p_valid, "%u", a->nac_p);
}
if (trackDataValid(&a->nac_v_valid) && (forceEmit || a->nac_v != a->fatsv_emitted_nac_v)) {
p = appendFATSVMeta(p, end, "nac_v", a, &a->nac_v_valid, "%u", a->nac_v);
}
if (trackDataValid(&a->sil_valid) && (forceEmit || a->sil != a->fatsv_emitted_sil)) {
p = appendFATSVMeta(p, end, "sil", a, &a->sil_valid, "%u", a->sil);
}
if (trackDataValid(&a->sil_valid) && (forceEmit || a->sil_type != a->fatsv_emitted_sil_type)) {
p = appendFATSVMeta(p, end, "sil_type", a, &a->sil_valid, "%s", sil_type_enum_string(a->sil_type));
}
if (trackDataValid(&a->nic_baro_valid) && (forceEmit || a->nic_baro != a->fatsv_emitted_nic_baro)) {
p = appendFATSVMeta(p, end, "nic_baro", a, &a->nic_baro_valid, "%u", a->nic_baro);
}
// only emit alt, speed, latlon, track etc if they have been received since the last time
// and are not stale
char *dataStart = p;
// special cases
if (airgroundValid)
p = appendFATSVMeta(p, end, "airGround", a, &a->airground_valid, "%s", airground_enum_string(a->airground));
if (squawkValid)
p = appendFATSVMeta(p, end, "squawk", a, &a->squawk_valid, "%04x", a->squawk);
if (callsignValid)
p = appendFATSVMeta(p, end, "ident", a, &a->callsign_valid, "{%s}", a->callsign);
if (altValid)
p = appendFATSVMeta(p, end, "alt", a, &a->altitude_baro_valid, "%d", a->altitude_baro);
if (positionValid) {
p = appendFATSVMeta(p, end, "position", a, &a->position_valid, "{%.5f %.5f %u %u}", a->lat, a->lon, a->pos_nic, a->pos_rc);
}
p = appendFATSVMeta(p, end, "alt_gnss", a, &a->altitude_geom_valid, "%d", a->altitude_geom);
p = appendFATSVMeta(p, end, "vrate", a, &a->baro_rate_valid, "%d", a->baro_rate);
p = appendFATSVMeta(p, end, "vrate_geom", a, &a->geom_rate_valid, "%d", a->geom_rate);
p = appendFATSVMeta(p, end, "speed", a, &a->gs_valid, "%.1f", a->gs);
p = appendFATSVMeta(p, end, "speed_ias", a, &a->ias_valid, "%u", a->ias);
p = appendFATSVMeta(p, end, "speed_tas", a, &a->tas_valid, "%u", a->tas);
p = appendFATSVMeta(p, end, "mach", a, &a->mach_valid, "%.3f", a->mach);
p = appendFATSVMeta(p, end, "track", a, &a->track_valid, "%.1f", a->track);
p = appendFATSVMeta(p, end, "track_rate", a, &a->track_rate_valid, "%.2f", a->track_rate);
p = appendFATSVMeta(p, end, "roll", a, &a->roll_valid, "%.1f", a->roll);
p = appendFATSVMeta(p, end, "heading_magnetic", a, &a->mag_heading_valid, "%.1f", a->mag_heading);
p = appendFATSVMeta(p, end, "heading_true", a, &a->true_heading_valid, "%.1f", a->true_heading);
p = appendFATSVMeta(p, end, "nav_alt_mcp", a, &a->nav_altitude_mcp_valid, "%u", a->nav_altitude_mcp);
p = appendFATSVMeta(p, end, "nav_alt_fms", a, &a->nav_altitude_fms_valid, "%u", a->nav_altitude_fms);
p = appendFATSVMeta(p, end, "nav_alt_src", a, &a->nav_altitude_src_valid, "%s", nav_altitude_source_enum_string(a->nav_altitude_src));
p = appendFATSVMeta(p, end, "nav_heading", a, &a->nav_heading_valid, "%.1f", a->nav_heading);
p = appendFATSVMeta(p, end, "nav_modes", a, &a->nav_modes_valid, "{%s}", nav_modes_flags_string(a->nav_modes));
p = appendFATSVMeta(p, end, "nav_qnh", a, &a->nav_qnh_valid, "%.1f", a->nav_qnh);
p = appendFATSVMeta(p, end, "emergency", a, &a->emergency_valid, "%s", emergency_enum_string(a->emergency));
// if we didn't get anything interesting, bail out.
// We don't need to do anything special to unwind prepareWrite().
if (p == dataStart) {
continue;
}
--p; // remove last tab
p = safe_snprintf(p, end, "\n");
if (p < end)
completeWrite(&Modes.fatsv_out, p);
else
fprintf(stderr, "fatsv: output too large (max %d, overran by %d)\n", TSV_MAX_PACKET_SIZE, (int) (p - end));
a->fatsv_emitted_altitude_baro = a->altitude_baro;
a->fatsv_emitted_altitude_geom = a->altitude_geom;
a->fatsv_emitted_baro_rate = a->baro_rate;
a->fatsv_emitted_geom_rate = a->geom_rate;
a->fatsv_emitted_gs = a->gs;
a->fatsv_emitted_ias = a->ias;
a->fatsv_emitted_tas = a->tas;
a->fatsv_emitted_mach = a->mach;
a->fatsv_emitted_track = a->track;
a->fatsv_emitted_track_rate = a->track_rate;
a->fatsv_emitted_roll = a->roll;
a->fatsv_emitted_mag_heading = a->mag_heading;
a->fatsv_emitted_true_heading = a->true_heading;
a->fatsv_emitted_airground = a->airground;
a->fatsv_emitted_nav_altitude_mcp = a->nav_altitude_mcp;
a->fatsv_emitted_nav_altitude_fms = a->nav_altitude_fms;
a->fatsv_emitted_nav_altitude_src = a->nav_altitude_src;
a->fatsv_emitted_nav_heading = a->nav_heading;
a->fatsv_emitted_nav_modes = a->nav_modes;
a->fatsv_emitted_nav_qnh = a->nav_qnh;
memcpy(a->fatsv_emitted_callsign, a->callsign, sizeof(a->fatsv_emitted_callsign));
a->fatsv_emitted_addrtype = a->addrtype;
a->fatsv_emitted_adsb_version = a->adsb_version;
a->fatsv_emitted_category = a->category;
a->fatsv_emitted_squawk = a->squawk;
a->fatsv_emitted_nac_p = a->nac_p;
a->fatsv_emitted_nac_v = a->nac_v;
a->fatsv_emitted_sil = a->sil;
a->fatsv_emitted_sil_type = a->sil_type;
a->fatsv_emitted_nic_baro = a->nic_baro;
a->fatsv_emitted_emergency = a->emergency;
a->fatsv_last_emitted = now;
if (forceEmit) {
a->fatsv_last_force_emit = now;
}
}
}
//
// Perform periodic network work
//
void modesNetPeriodicWork(void) {
struct client *c, **prev;
struct net_service *s;
uint64_t now = mstime();
int need_flush = 0;
// Accept new connections
modesAcceptClients();
// Read from clients
for (c = Modes.clients; c; c = c->next) {
if (!c->service)
continue;
if (c->service->read_handler)
modesReadFromClient(c);
}
// Generate FATSV output
writeFATSV();
// If we have generated no messages for a while, send
// a heartbeat
if (Modes.net_heartbeat_interval) {
for (s = Modes.services; s; s = s->next) {
if (s->writer &&
s->connections &&
s->writer->send_heartbeat &&
(s->writer->lastWrite + Modes.net_heartbeat_interval) <= now) {
s->writer->send_heartbeat(s);
}
}
}
// If we have data that has been waiting to be written for a while,
// write it now.
for (s = Modes.services; s; s = s->next) {
if (s->writer &&
s->writer->dataUsed &&
(need_flush || (s->writer->lastWrite + Modes.net_output_flush_interval) <= now)) {
flushWrites(s->writer);
}
}
// Unlink and free closed clients
for (prev = &Modes.clients, c = *prev; c; c = *prev) {
if (c->fd == -1) {
// Recently closed, prune from list
*prev = c->next;
free(c);
} else {
prev = &c->next;
}
}
}
//
// =============================== Network IO ===========================
//