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Basic tidy up of the modesInit() function

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Malcolm Robb 2013-04-10 12:16:25 +01:00
parent f1935b280c
commit f806f1899e
1 changed files with 23 additions and 20 deletions
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dump1090.c
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@ -304,27 +304,29 @@ void modesInit(void) {
pthread_mutex_init(&Modes.data_mutex,NULL); pthread_mutex_init(&Modes.data_mutex,NULL);
pthread_cond_init(&Modes.data_cond,NULL); pthread_cond_init(&Modes.data_cond,NULL);
/* We add a full message minus a final bit to the length, so that we
* can carry the remaining part of the buffer that we can't process // Allocate the various buffers used by Modes
* in the message detection loop, back at the start of the next data if ( ((Modes.icao_cache = (uint32_t *) malloc(sizeof(uint32_t) * MODES_ICAO_CACHE_LEN * 2) ) == NULL) ||
* to process. This way we are able to also detect messages crossing ((Modes.data = (uint16_t *) malloc(MODES_ASYNC_BUF_SIZE) ) == NULL) ||
* two reads. */ ((Modes.magnitude = (uint16_t *) malloc(MODES_ASYNC_BUF_SIZE+MODES_PREAMBLE_SIZE+MODES_LONG_MSG_SIZE) ) == NULL) ||
Modes.data_ready = 0; ((Modes.maglut = (uint16_t *) malloc(sizeof(uint16_t) * 256 * 256) ) == NULL) )
Modes.timestampBlk = 0; {
/* Allocate the ICAO address cache. We use two uint32_t for every
* entry because it's a addr / timestamp pair for every entry. */
Modes.icao_cache = (uint32_t *) malloc(sizeof(uint32_t)*MODES_ICAO_CACHE_LEN*2);
memset(Modes.icao_cache,0,sizeof(uint32_t)*MODES_ICAO_CACHE_LEN*2);
Modes.aircrafts = NULL;
Modes.interactive_last_update = 0;
if ((Modes.data = (uint16_t *) malloc(MODES_ASYNC_BUF_SIZE)) == NULL ||
(Modes.magnitude = (uint16_t *) malloc(MODES_ASYNC_BUF_SIZE+MODES_PREAMBLE_SIZE+MODES_LONG_MSG_SIZE)) == NULL) {
fprintf(stderr, "Out of memory allocating data buffer.\n"); fprintf(stderr, "Out of memory allocating data buffer.\n");
exit(1); exit(1);
} }
// Clear the buffers that have just been allocated, just in-case
memset(Modes.icao_cache, 0, sizeof(uint32_t) * MODES_ICAO_CACHE_LEN * 2);
memset(Modes.data, 127, MODES_ASYNC_BUF_SIZE); memset(Modes.data, 127, MODES_ASYNC_BUF_SIZE);
memset(Modes.magnitude, 0, MODES_ASYNC_BUF_SIZE+MODES_PREAMBLE_SIZE+MODES_LONG_MSG_SIZE); memset(Modes.magnitude, 0, MODES_ASYNC_BUF_SIZE+MODES_PREAMBLE_SIZE+MODES_LONG_MSG_SIZE);
// The ICAO address cache. We use two uint32_t for every
// entry because it's a addr / timestamp pair for every entry.
Modes.timestampBlk = 0;
Modes.data_ready = 0;
Modes.aircrafts = NULL;
Modes.interactive_last_update = 0;
/* Populate the I/Q -> Magnitude lookup table. It is used because /* Populate the I/Q -> Magnitude lookup table. It is used because
* sqrt or round may be expensive and may vary a lot depending on * sqrt or round may be expensive and may vary a lot depending on
* the libc used. * the libc used.
@ -332,12 +334,13 @@ void modesInit(void) {
* We scale to 0-255 range multiplying by 1.4 in order to ensure that * We scale to 0-255 range multiplying by 1.4 in order to ensure that
* every different I/Q pair will result in a different magnitude value, * every different I/Q pair will result in a different magnitude value,
* not losing any resolution. */ * not losing any resolution. */
Modes.maglut = malloc(256*256*2);
for (i = 0; i <= 255; i++) { for (i = 0; i <= 255; i++) {
int mag_i = i - 127; int mag_i = i - 127;
for (q = 0; q <= 255; q++) { for (q = 0; q <= 255; q++) {
int mag_q = q - 127; int mag_q = q - 127;
Modes.maglut[i*256+q] = round(sqrt((mag_i*mag_i)+(mag_q*mag_q))*360); int mag = 0;
mag = (int) round(sqrt((mag_i*mag_i)+(mag_q*mag_q)) * 360);
Modes.maglut[(i*256)+q] = (uint16_t) min(mag,65535);
} }
} }