static bool noHandleOption(int argc, char **argv, int *jptr)
{
MODES_NOTUSED(argc);
MODES_NOTUSED(argv);
MODES_NOTUSED(jptr);
return false;
}
//
//=========================================================================
//
// We use a thread reading data in background, while the main thread
// handles decoding and visualization of data to the user.
//
// The reading thread calls the RTLSDR API to read data asynchronously, and
// uses a callback to populate the data buffer.
//
// A Mutex is used to avoid races with the decoding thread.
//
void rtlsdrCallback(unsigned char *buf, uint32_t len, void *ctx) {
MODES_NOTUSED(ctx);
// Lock the data buffer variables before accessing them
pthread_mutex_lock(&Modes.data_mutex);
Modes.iDataIn &= (MODES_ASYNC_BUF_NUMBER-1); // Just incase!!!
// Get the system time for this block
ftime(&Modes.stSystemTimeRTL[Modes.iDataIn]);
if (len > MODES_ASYNC_BUF_SIZE) {len = MODES_ASYNC_BUF_SIZE;}
// Queue the new data
Modes.pData[Modes.iDataIn] = (uint16_t *) buf;
Modes.iDataIn = (MODES_ASYNC_BUF_NUMBER-1) & (Modes.iDataIn + 1);
Modes.iDataReady = (MODES_ASYNC_BUF_NUMBER-1) & (Modes.iDataIn - Modes.iDataOut);
if (Modes.iDataReady == 0) {
// Ooooops. We've just received the MODES_ASYNC_BUF_NUMBER'th outstanding buffer
// This means that RTLSDR is currently overwriting the MODES_ASYNC_BUF_NUMBER+1
// buffer, but we havent yet processed it, so we're going to lose it. There
// isn't much we can do to recover the lost data, but we can correct things to
// avoid any additional problems.
Modes.iDataOut = (MODES_ASYNC_BUF_NUMBER-1) & (Modes.iDataOut+1);
Modes.iDataReady = (MODES_ASYNC_BUF_NUMBER-1);
Modes.iDataLost++;
}
// Signal to the other thread that new data is ready, and unlock
pthread_cond_signal(&Modes.data_cond);
pthread_mutex_unlock(&Modes.data_mutex);
}
//
//=========================================================================
//
// 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.
//
int decodeBinMessage(struct client *c, char *p) {
int msgLen = 0;
unsigned char msg[MODES_LONG_MSG_BYTES];
struct modesMessage mm;
MODES_NOTUSED(c);
memset(&mm, 0, sizeof(mm));
if ((*p == '1') && (Modes.mode_ac)) { // skip ModeA/C unless user enables --modes-ac
msgLen = MODEAC_MSG_BYTES;
} else if (*p == '2') {
msgLen = MODES_SHORT_MSG_BYTES;
} else if (*p == '3') {
msgLen = MODES_LONG_MSG_BYTES;
}
if (msgLen) {
// 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;
p += 7; // Skip the timestamp
mm.signalLevel = *p++; // Grab the signal level
memcpy(msg, p, msgLen); // and the data
if (msgLen == MODEAC_MSG_BYTES) { // ModeA or ModeC
decodeModeAMessage(&mm, ((msg[0] << 8) | msg[1]));
} else {
decodeModesMessage(&mm, msg);
}
useModesMessage(&mm);
}
return (0);
}
/* We read data using a thread, so the main thread only handles decoding
* without caring about data acquisition. */
void *readerThreadEntryPoint(void *arg) {
MODES_NOTUSED(arg);
rtlsdr_read_async(Modes.dev, rtlsdrCallback, NULL,
MODES_ASYNC_BUF_NUMBER,
MODES_DATA_LEN);
Modes.exit --;
return NULL;
}
//
//=========================================================================
//
// 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.
//
int decodeBinMessage(struct client *c, char *p) {
int msgLen = 0;
int j;
char ch;
char * ptr;
unsigned char msg[MODES_LONG_MSG_BYTES];
struct modesMessage mm;
MODES_NOTUSED(c);
memset(&mm, 0, sizeof(mm));
ch = *p++; /// Get the message type
if (0x1A == ch) {p++;}
if ((ch == '1') && (Modes.mode_ac)) { // skip ModeA/C unless user enables --modes-ac
msgLen = MODEAC_MSG_BYTES;
} else if (ch == '2') {
msgLen = MODES_SHORT_MSG_BYTES;
} else if (ch == '3') {
msgLen = MODES_LONG_MSG_BYTES;
}
if (msgLen) {
// 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;
ptr = (char*) &mm.timestampMsg;
for (j = 0; j < 6; j++) { // Grab the timestamp (big endian format)
ptr[5-j] = ch = *p++;
if (0x1A == ch) {p++;}
}
mm.signalLevel = ch = *p++; // Grab the signal level
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
decodeModeAMessage(&mm, ((msg[0] << 8) | msg[1]));
} else {
decodeModesMessage(&mm, msg);
}
useModesMessage(&mm);
}
return (0);
}
//
//=========================================================================
//
// We use a thread reading data in background, while the main thread
// handles decoding and visualization of data to the user.
//
// The reading thread calls the RTLSDR API to read data asynchronously, and
// uses a callback to populate the data buffer.
//
// A Mutex is used to avoid races with the decoding thread.
//
void rtlsdrCallback(unsigned char *buf, uint32_t len, void *ctx) {
MODES_NOTUSED(ctx);
pthread_mutex_lock(&Modes.data_mutex);
ftime(&Modes.stSystemTimeRTL);
if (len > MODES_ASYNC_BUF_SIZE) len = MODES_ASYNC_BUF_SIZE;
// Read the new data
memcpy(Modes.data, buf, len);
Modes.data_ready = 1;
// Signal to the other thread that new data is ready
pthread_cond_signal(&Modes.data_cond);
pthread_mutex_unlock(&Modes.data_mutex);
}
/* We use a thread reading data in background, while the main thread
* handles decoding and visualization of data to the user.
*
* The reading thread calls the RTLSDR API to read data asynchronously, and
* uses a callback to populate the data buffer.
* A Mutex is used to avoid races with the decoding thread. */
void rtlsdrCallback(unsigned char *buf, uint32_t len, void *ctx) {
MODES_NOTUSED(ctx);
pthread_mutex_lock(&Modes.data_mutex);
if (len > MODES_DATA_LEN) len = MODES_DATA_LEN;
/* Move the last part of the previous buffer, that was not processed,
* on the start of the new buffer. */
memcpy(Modes.data, Modes.data+MODES_DATA_LEN, (MODES_FULL_LEN-1)*4);
/* Read the new data. */
memcpy(Modes.data+(MODES_FULL_LEN-1)*4, buf, len);
Modes.data_ready = 1;
/* Signal to the other thread that new data is ready */
pthread_cond_signal(&Modes.data_cond);
pthread_mutex_unlock(&Modes.data_mutex);
}
//
//=========================================================================
//
// We read data using a thread, so the main thread only handles decoding
// without caring about data acquisition
//
void *readerThreadEntryPoint(void *arg) {
MODES_NOTUSED(arg);
if (Modes.filename == NULL) {
rtlsdr_read_async(Modes.dev, rtlsdrCallback, NULL,
MODES_ASYNC_BUF_NUMBER,
MODES_ASYNC_BUF_SIZE);
} else {
readDataFromFile();
}
// Signal to the other thread that new data is ready - dummy really so threads don't mutually lock
pthread_cond_signal(&Modes.data_cond);
pthread_mutex_unlock(&Modes.data_mutex);
#ifndef _WIN32
pthread_exit(NULL);
#else
return NULL;
#endif
}
void *readerThreadEntryPoint(void *arg) {
MODES_NOTUSED(arg);
start_cpu_timing(&reader_thread_start); // we accumulate in rtlsdrCallback() or readDataFromFile()
if (Modes.filename == NULL) {
while (!Modes.exit) {
rtlsdr_read_async(Modes.dev, rtlsdrCallback, NULL,
MODES_RTL_BUFFERS,
MODES_RTL_BUF_SIZE);
if (!Modes.exit) {
log_with_timestamp("Warning: lost the connection to the RTLSDR device.");
rtlsdr_close(Modes.dev);
Modes.dev = NULL;
do {
sleep(5);
log_with_timestamp("Trying to reconnect to the RTLSDR device..");
} while (!Modes.exit && modesInitRTLSDR() < 0);
}
}
if (Modes.dev != NULL) {
rtlsdr_close(Modes.dev);
Modes.dev = NULL;
}
} else {
readDataFromFile();
}
// Wake the main thread (if it's still waiting)
pthread_mutex_lock(&Modes.data_mutex);
Modes.exit = 1; // just in case
pthread_cond_signal(&Modes.data_cond);
pthread_mutex_unlock(&Modes.data_mutex);
#ifndef _WIN32
pthread_exit(NULL);
#else
return NULL;
#endif
}
//
// ============================= Utility functions ==========================
//
void sigintHandler(int dummy) {
MODES_NOTUSED(dummy);
signal(SIGINT, SIG_DFL); // reset signal handler - bit extra safety
Modes.exit = 1; // Signal to threads that we are done
}
//
//=========================================================================
//
// 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.
//
int decodeHexMessage(struct client *c, char *hex) {
int l = strlen(hex), j;
unsigned char msg[MODES_LONG_MSG_BYTES];
struct modesMessage mm;
MODES_NOTUSED(c);
memset(&mm, 0, sizeof(mm));
// 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 = 0xFF;
// 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]);
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;
}
if (l == (MODEAC_MSG_BYTES * 2)) { // ModeA or ModeC
decodeModeAMessage(&mm, ((msg[0] << 8) | msg[1]));
} else { // Assume ModeS
decodeModesMessage(&mm, msg);
}
useModesMessage(&mm);
return (0);
}
static void sigtermHandler(int dummy) {
MODES_NOTUSED(dummy);
signal(SIGTERM, SIG_DFL); // reset signal handler - bit extra safety
Modes.exit = 1; // Signal to threads that we are done
log_with_timestamp("Caught SIGTERM, shutting down..\n");
}
void rtlsdrCallback(unsigned char *buf, uint32_t len, void *ctx) {
struct mag_buf *outbuf;
struct mag_buf *lastbuf;
uint32_t slen;
unsigned next_free_buffer;
unsigned free_bufs;
unsigned block_duration;
static int was_odd = 0; // paranoia!!
static int dropping = 0;
MODES_NOTUSED(ctx);
// Lock the data buffer variables before accessing them
pthread_mutex_lock(&Modes.data_mutex);
if (Modes.exit) {
rtlsdr_cancel_async(Modes.dev); // ask our caller to exit
}
next_free_buffer = (Modes.first_free_buffer + 1) % MODES_MAG_BUFFERS;
outbuf = &Modes.mag_buffers[Modes.first_free_buffer];
lastbuf = &Modes.mag_buffers[(Modes.first_free_buffer + MODES_MAG_BUFFERS - 1) % MODES_MAG_BUFFERS];
free_bufs = (Modes.first_filled_buffer - next_free_buffer + MODES_MAG_BUFFERS) % MODES_MAG_BUFFERS;
// Paranoia! Unlikely, but let's go for belt and suspenders here
if (len != MODES_RTL_BUF_SIZE) {
fprintf(stderr, "weirdness: rtlsdr gave us a block with an unusual size (got %u bytes, expected %u bytes)\n",
(unsigned)len, (unsigned)MODES_RTL_BUF_SIZE);
if (len > MODES_RTL_BUF_SIZE) {
// wat?! Discard the start.
unsigned discard = (len - MODES_RTL_BUF_SIZE + 1) / 2;
outbuf->dropped += discard;
buf += discard*2;
len -= discard*2;
}
}
if (was_odd) {
// Drop a sample so we are in sync with I/Q samples again (hopefully)
++buf;
--len;
++outbuf->dropped;
}
was_odd = (len & 1);
slen = len/2;
if (free_bufs == 0 || (dropping && free_bufs < MODES_MAG_BUFFERS/2)) {
// FIFO is full. Drop this block.
dropping = 1;
outbuf->dropped += slen;
pthread_mutex_unlock(&Modes.data_mutex);
return;
}
dropping = 0;
pthread_mutex_unlock(&Modes.data_mutex);
// Compute the sample timestamp and system timestamp for the start of the block
outbuf->sampleTimestamp = lastbuf->sampleTimestamp + 12e6 * (lastbuf->length + outbuf->dropped) / Modes.sample_rate;
block_duration = 1e9 * slen / Modes.sample_rate;
// Get the approx system time for the start of this block
clock_gettime(CLOCK_REALTIME, &outbuf->sysTimestamp);
outbuf->sysTimestamp.tv_nsec -= block_duration;
normalize_timespec(&outbuf->sysTimestamp);
// Copy trailing data from last block (or reset if not valid)
if (outbuf->dropped == 0 && lastbuf->length >= Modes.trailing_samples) {
memcpy(outbuf->data, lastbuf->data + lastbuf->length - Modes.trailing_samples, Modes.trailing_samples * sizeof(uint16_t));
} else {
memset(outbuf->data, 0, Modes.trailing_samples * sizeof(uint16_t));
}
// Convert the new data
outbuf->length = slen;
convert_samples(buf, &outbuf->data[Modes.trailing_samples], slen, &outbuf->total_power);
// Push the new data to the demodulation thread
pthread_mutex_lock(&Modes.data_mutex);
Modes.mag_buffers[next_free_buffer].dropped = 0;
Modes.mag_buffers[next_free_buffer].length = 0; // just in case
Modes.first_free_buffer = next_free_buffer;
// accumulate CPU while holding the mutex, and restart measurement
end_cpu_timing(&reader_thread_start, &Modes.reader_cpu_accumulator);
start_cpu_timing(&reader_thread_start);
pthread_cond_signal(&Modes.data_cond);
pthread_mutex_unlock(&Modes.data_mutex);
}