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rtl_sdr_fm: add additional bounds checks and cleanup extra line

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This commit is contained in:
arancormonk
2025-09-04 12:53:54 -04:00
parent a866d98e75
commit da8b9b6116
1 changed files with 21 additions and 11 deletions
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32
src/rtl_sdr_fm.cpp
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@@ -406,7 +406,6 @@ static void DSD_FME_TARGET_ATTR("avx2") widen_rotate90_u8_to_s16_bias127_avx2(co
}
}
/**
* SSE2: widen unsigned bytes to signed 16-bit centered at 127.
*/
@@ -1691,7 +1690,9 @@ void rotate_90(unsigned char *buf, uint32_t len)
{
uint32_t i;
unsigned char tmp;
for (i=0; i<len; i+=8) {
/* Process only full 8-byte blocks (4 IQ pairs) to avoid overrun */
uint32_t full = len - (len % 8);
for (i=0; i<full; i+=8) {
/* uint8_t negation = 255 - x */
tmp = 255 - buf[i+3];
buf[i+3] = buf[i+2];
@@ -1748,7 +1749,8 @@ void low_pass(struct demod_state *d)
int low_pass_simple(int16_t *signal2, int len, int step)
{
int i, i2, sum;
for(i=0; i < len; i+=step) {
if (step <= 0) return len;
for(i=0; i + (step-1) < len; i+=step) {
sum = 0;
for(i2=0; i2<step; i2++) {
sum += (int)signal2[i + i2];
@@ -1759,8 +1761,11 @@ int low_pass_simple(int16_t *signal2, int len, int step)
}
/* Duplicate the final sample to provide one-sample lookahead for callers
that expect at least one extra element. */
signal2[i/step + 1] = signal2[i/step];
return len / step;
int out_len = len / step;
if (out_len > 0) {
signal2[out_len] = signal2[out_len - 1];
}
return out_len;
}
/**
@@ -2667,7 +2672,7 @@ void full_demod(struct demod_state *d)
*/
static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
{
int i;
struct dongle_state *s = static_cast<dongle_state*>(ctx);
/* One-time: ensure the USB callback thread gets RT scheduling/affinity if enabled */
{
@@ -2683,9 +2688,11 @@ static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
if (!ctx) {
return;}
if (s->mute) {
for (i=0; i<s->mute; i++) {
buf[i] = 127;}
s->mute = 0;
/* Clamp mute length to buffer size to avoid overwrite; carry remainder */
uint32_t m = (uint32_t)s->mute;
if (m > len) m = len;
memset(buf, 127, m);
s->mute -= (int)m;
}
/* Convert incoming u8 I/Q and write directly into input ring without extra copy */
size_t need = len;
@@ -3538,7 +3545,7 @@ static void *socket_thread_fn(void *arg) {
int new_freq;
while((n = read(sockfd,buffer,5)) != 0) {
if(buffer[0] == 0) {
if (n == 5 && buffer[0] == 0) {
new_freq = chars_to_int(buffer);
dongle.freq = new_freq;
optimal_settings(new_freq, demod.rate_in);
@@ -3980,7 +3987,10 @@ long int rtl_return_rms(void)
//I've found that just using a sample size of 160 will give us a good approximation without killing the CPU
// Return mean power (squared RMS) for soft squelch decisions (sqrt-free)
// sr = mean_power(demod.lowpassed, demod.lp_len, 1);
sr = mean_power(demod.lowpassed, 160, 1);
int n = demod.lp_len;
if (n > 160) n = 160;
if (n < 0) n = 0;
sr = mean_power(demod.lowpassed, n, 1);
// #endif
return (sr);
}