From 08a91f1fa3a5888c2a97943c9a36384e30f21db1 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 15 Feb 2010 19:50:35 +0100
Subject: sleep between two sounds

---
 dbverify.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/dbverify.c b/dbverify.c
index 6b7121b..e6d9dfe 100644
--- a/dbverify.c
+++ b/dbverify.c
@@ -5,11 +5,11 @@
 #include <asoundlib.h>
 
 static double linear_to_dB(double v) {
-    return 20.0 * log10(v);
+        return 20.0 * log10(v);
 }
 
 static double dB_to_linear(double v) {
-    return pow(10.0, v / 20.0);
+        return pow(10.0, v / 20.0);
 }
 
 static float *generate_signal(unsigned n_samples, double amplitude, double frequency) {
@@ -31,7 +31,7 @@ static snd_pcm_t *open_pcm(const char *name, unsigned *rate) {
         snd_pcm_hw_params_t *hw;
         snd_pcm_uframes_t t;
         snd_output_t *output = NULL;
-        int dir = 1;
+        int dir = 0;
 
         snd_pcm_hw_params_alloca(&hw);
 
@@ -118,6 +118,9 @@ static int play_pcm(snd_pcm_t *pcm, float *samples, unsigned n_samples) {
                         if ((r = snd_pcm_recover(pcm, t, 0)) >= 0)
                                 continue;
 
+                        if (snd_pcm_prepare(pcm) >= 0)
+                                continue;
+
                         fprintf(stderr, "Failed to write samples: %s\n", snd_strerror(r));
                         return r;
                 }
@@ -126,7 +129,7 @@ static int play_pcm(snd_pcm_t *pcm, float *samples, unsigned n_samples) {
                 samples += t;
         }
 
-        /* snd_pcm_drain(pcm); */
+        snd_pcm_drain(pcm);
         return 0;
 }
 
@@ -221,6 +224,7 @@ int main(int argc, char *argv[]) {
         long min_discrete, max_discrete, step1, step2, step1_alsa_dB, step2_alsa_dB;
         double step1_dB, step2_dB, attenuation;
         float *signal1 = NULL, *signal2 = NULL;
+        double amplitude = 0.75;
 
         if (argc < 3 || argc > 5) {
                 fprintf(stderr,
@@ -303,14 +307,14 @@ int main(int argc, char *argv[]) {
 
         printf("Attenuation factor is %0.4f (%0.2f dB).\n", attenuation, linear_to_dB(attenuation));
 
-        if (!(signal1 = generate_signal(rate, 1.0, 440)) |
-            !(signal2 = generate_signal(rate, attenuation, 440))) {
+        if (!(signal1 = generate_signal(rate, amplitude, 440)) |
+            !(signal2 = generate_signal(rate, amplitude * attenuation, 440))) {
                 fprintf(stderr, "Failed to generate test signal.\n");
                 goto finish;
         }
 
         for (;;) {
-                printf("Playing 1s of audio at amplitude %0.4f, mixer set to %li (%0.2f dB).\n", 1.0, step1, step1_dB);
+                printf("Playing 1s of audio at amplitude %0.4f, mixer set to %li (%0.2f dB).\n", amplitude, step1, step1_dB);
 
                 if ((r = snd_mixer_selem_set_playback_volume_all(selem, step1)) < 0) {
                         fprintf(stderr, "Failed to set element volume step: %s\n", snd_strerror(r));
@@ -320,7 +324,10 @@ int main(int argc, char *argv[]) {
                 if (play_pcm(pcm, signal1, rate) < 0)
                         goto finish;
 
-                printf("Playing 1s of audio at amplitude %0.4f, mixer set to %li (%0.2f dB).\n", attenuation, step2, step2_dB);
+                printf("Sleeping 1s...\n");
+                sleep(1);
+
+                printf("Playing 1s of audio at amplitude %0.4f, mixer set to %li (%0.2f dB).\n", amplitude*attenuation, step2, step2_dB);
 
                 if ((r = snd_mixer_selem_set_playback_volume_all(selem, step2)) < 0) {
                         fprintf(stderr, "Failed to set element volume step: %s\n", snd_strerror(r));
@@ -330,6 +337,9 @@ int main(int argc, char *argv[]) {
                 if (play_pcm(pcm, signal2, rate) < 0)
                         goto finish;
 
+                printf("Sleeping 1s...\n");
+                sleep(1);
+
                 printf("Looping. Press C-c to quit.\n");
         }
 
-- 
cgit