diff options
| -rw-r--r-- | util/spkmodem_recv/spkmodem-recv.c | 38 |
1 files changed, 31 insertions, 7 deletions
diff --git a/util/spkmodem_recv/spkmodem-recv.c b/util/spkmodem_recv/spkmodem-recv.c index 7bfdaff3..52466215 100644 --- a/util/spkmodem_recv/spkmodem-recv.c +++ b/util/spkmodem_recv/spkmodem-recv.c @@ -36,10 +36,16 @@ #define THRESHOLD 500 +#define READ_BUF 4096 + struct decoder_state { signed short frame[MAX_SAMPLES]; unsigned char pulse[MAX_SAMPLES]; + signed short inbuf[READ_BUF]; + size_t inpos; + size_t inlen; + int ringpos; int sep_pos; @@ -58,6 +64,7 @@ static const char *argv0; static void handle_audio(struct decoder_state *st); static int valid_signal(struct decoder_state *st); static void decode_pulse(struct decoder_state *st); +static signed short read_sample(struct decoder_state *st); static int set_ascii_bit(struct decoder_state *st); static void print_char(struct decoder_state *st); static void print_stats(struct decoder_state *st); @@ -151,7 +158,6 @@ valid_signal(struct decoder_state *st) static void decode_pulse(struct decoder_state *st) { - size_t n; unsigned char old_ring, old_sep; unsigned char new_pulse; @@ -162,12 +168,7 @@ decode_pulse(struct decoder_state *st) st->freq_data += old_sep; st->freq_separator -= old_sep; - n = fread(&st->frame[st->ringpos], sizeof(st->frame[0]), 1, stdin); - if (n != 1) { - if (feof(stdin)) - exit(EXIT_SUCCESS); - err(errno, "stdin read"); - } + st->frame[st->ringpos] = read_sample(st); new_pulse = abs(st->frame[st->ringpos]) > THRESHOLD; st->pulse[st->ringpos] = new_pulse; @@ -184,6 +185,29 @@ decode_pulse(struct decoder_state *st) st->sample_count++; } +static signed short +read_sample(struct decoder_state *st) +{ + size_t n; + + if (st->inpos >= st->inlen) { + + n = fread(st->inbuf, sizeof(st->inbuf[0]), + READ_BUF, stdin); + + if (n == 0) { + if (feof(stdin)) + exit(EXIT_SUCCESS); + err(errno, "stdin read"); + } + + st->inpos = 0; + st->inlen = n; + } + + return st->inbuf[st->inpos++]; +} + static int set_ascii_bit(struct decoder_state *st) { |