From 725b06e1e8b93148a06f7c0028b626e58c288b4d Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 12 Oct 2025 13:39:18 +0200
Subject: [PATCH 01/26] added binary build to .gitignore

---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 .gitignore

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..dab040f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+cpiped

From 6b262c06b8a825a60c9c63fd01183a172b779adb Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 12 Oct 2025 13:13:59 +0200
Subject: [PATCH 02/26] fixed mylog code aesthetic

---
 cpiped.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 1899b34..1e825e8 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -38,15 +38,17 @@ int writefd = 0;
 
 void mylog(int level, const char *format, ...)
 {
-    va_list args;
-    va_start (args, format);
+  va_list args;
+  va_start (args, format);
 
-    if (daemonize) {
-        vsyslog(level, format, args);
-    } else {
+  if (daemonize) {
+    vsyslog(level, format, args);
+  } else {
     vprintf(format, args);
-    }
-    va_end(args);
+  }
+
+  va_end(args);
+}
 }
 
 void myterm() {

From bea1ce28153b55613cda058cb244db7758a7ef74 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 12 Oct 2025 13:16:58 +0200
Subject: [PATCH 03/26] introduced log verbosity control functionality

---
 cpiped.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/cpiped.c b/cpiped.c
index 1e825e8..c69d4d3 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -33,6 +33,7 @@
 
 snd_pcm_t *handle;
 int daemonize = 0;
+int log_verb = 0;
 int readfd = 0;
 int writefd = 0;
 
@@ -49,6 +50,21 @@ void mylog(int level, const char *format, ...)
 
   va_end(args);
 }
+
+void mylogverb(int level, int msg_verb, const char *format, ...)
+{
+  va_list args_verb;
+  va_start (args_verb, format);
+
+  if (msg_verb <= log_verb) {
+    if (daemonize) {
+      vsyslog(level, format, args_verb);
+    } else {
+      vprintf(format, args_verb);
+    }
+  }
+
+  va_end(args_verb);
 }
 
 void myterm() {
@@ -113,7 +129,7 @@ int main(int argc, char *argv[]) {
   signal(SIGTERM, myterm);
 
   // Process command-line options and arguments
-  while ((opt = getopt(argc, argv, "d:b:s:e:t:D")) != -1) {
+  while ((opt = getopt(argc, argv, "d:b:s:e:t:Dv")) != -1) {
     switch (opt) {
     case 'd':
       capdev = optarg;
@@ -151,6 +167,9 @@ int main(int argc, char *argv[]) {
     case 'D':
       daemonize = 1;
       break;
+    case 'v':
+      log_verb = 1;
+      break;
     case '?':
       err = 1;
       mylog(LOG_ERR, "Invalid option: %s\n", argv[optind - 1]);
@@ -168,6 +187,7 @@ int main(int argc, char *argv[]) {
       " -e : command to run when silence detected\n"
       " -t : silence threshold (1 - 32767, [100])\n"
       " -D : daemonize\n"
+      " -v : enable more verbose logs\n"
       " FIFO : path to a named pipe\n", argv[0]);
     }
     goto error;

From a7c68939f9e3d09f333733498dc7e8db1d845657 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 12 Oct 2025 13:54:31 +0200
Subject: [PATCH 04/26] moved some LOG_INFO message under verbosity control

---
 cpiped.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index c69d4d3..ff77298 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -300,13 +300,13 @@ int main(int argc, char *argv[]) {
     
     if (bufused < capsize) {
       // Buffer is almost empty, don't send to pipe
-      mylog(LOG_INFO, "Filling buffer\n");
+      mylogverb(LOG_INFO, 1, "Filling buffer\n");
       fillbuf = 1;
     }
     
     if (bufused > (int)bufsize - 1 - capsize) {
       // Buffer is almost full, don't store captured samples
-      mylog(LOG_INFO, "Buffer full\n");
+      mylogverb(LOG_INFO, 0, "Buffer full\n");
       buffull = 1;
     }
 
@@ -348,9 +348,9 @@ int main(int argc, char *argv[]) {
       
       if (silent && soundcount > 1) {
         silent = 0;
-        mylog(LOG_INFO, "Sound detected. Last two values: %d, %d\n", prevpower, (int)power);
+        mylogverb(LOG_INFO, 0, "Sound detected. Last two values: %d, %d\n", prevpower, (int)power);
         if (strcmp(startcmd, "") != 0) {
-          mylog(LOG_INFO, "Running '%s'\n", startcmd);
+          mylogverb(LOG_INFO, 0, "Running '%s'\n", startcmd);
           if (system(startcmd) != 0) {
             mylog(LOG_ERR, "Error running start command.\n");
           }
@@ -359,9 +359,9 @@ int main(int argc, char *argv[]) {
       
       if (!silent && silentcount > 55) {
         silent = 1;
-        mylog(LOG_INFO, "Silence detected. Last two values: %d, %d\n", prevpower, (int)power);
+        mylogverb(LOG_INFO, 0, "Silence detected. Last two values: %d, %d\n", prevpower, (int)power);
         if (strcmp(endcmd, "") != 0) {
-          mylog(LOG_INFO, "Running '%s'\n", endcmd);
+          mylogverb(LOG_INFO, 0, "Running '%s'\n", endcmd);
           if (system(endcmd) != 0) {
             mylog(LOG_ERR, "Error running end command.\n");
           }

From 152d7d5bf936f9bd2f1c4f428add107db62fd9be Mon Sep 17 00:00:00 2001
From: natedreger <45026176+natedreger@users.noreply.github.com>
Date: Mon, 27 Apr 2020 12:27:17 -0500
Subject: [PATCH 05/26] Add files via upload

---
 NDpiped.c | 402 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 402 insertions(+)
 create mode 100644 NDpiped.c

diff --git a/NDpiped.c b/NDpiped.c
new file mode 100644
index 0000000..a87e8c5
--- /dev/null
+++ b/NDpiped.c
@@ -0,0 +1,402 @@
+/*
+ * Original cpiped.c code Copyright (C) 2014 Brian Fitzpatrick <brian@froxen.com>
+ * 
+ * Modifications 2020 Nate Dreger <info@natedreger.com>
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define _GNU_SOURCE
+
+// Use the newer ALSA API
+#define ALSA_PCM_NEW_HW_PARAMS_API
+
+#include <stdio.h>
+#include <math.h>
+#include <alsa/asoundlib.h>
+#include <signal.h>
+#include <sys/stat.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <errno.h>
+
+snd_pcm_t *handle;
+int daemonize = 0;
+int readfd = 0;
+int writefd = 0;
+
+void mylog(int level, const char *format, ...)
+{
+    va_list args;
+    va_start (args, format);
+
+    if (daemonize) {
+        vsyslog(level, format, args);
+    } else {
+    vprintf(format, args);
+    }
+    va_end(args);
+}
+
+void myterm() {
+  mylog(LOG_INFO, "Stopping due to interrupt/term.\n");
+  snd_pcm_drain(handle);
+  snd_pcm_close(handle);
+  if (readfd > 0) close(readfd);
+  if (writefd > 0) close(writefd);
+  exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char *argv[]) {
+  int rc;
+  int capsize;
+  snd_pcm_hw_params_t *params;
+  unsigned int val = 44100;
+  unsigned int capusec;
+  int dir;
+  snd_pcm_uframes_t frames;
+  char *capbuffer;
+  int16_t *scapbuffer;
+  char *capdev = "default";
+  char *fifonam;
+  struct stat status;
+  int readbytes = 0;
+  int writebytes = 0;
+  char *buf;
+  size_t bufsize = 176400;
+  int bufstart;
+  int bufend;
+  int bufused;
+  int fillbuf = 1;
+  int buffull = 0;
+  int bufendtoend;
+  int bufstarttoend;
+  int capcount = 0;
+  long power = 0;
+  int prevpower = 0;
+  int i;
+  int silent = 1;
+  int silentcount = 0;
+  int soundcount = 0;
+  char startcmd[1000] = "";
+  char endcmd[1000] = "";
+  int wrote = 0;
+  int silentt = 100;
+  
+  extern char *optarg;
+  extern int optind;
+  int opt;
+  int err = 0;
+  
+  pid_t pid, sid;
+  char pidstr[10];
+  char pidfile[50];
+  int pidfd;
+
+  // Ignore pipe signals
+  signal(SIGPIPE, SIG_IGN);
+  // Flush the hardware buffer on interrupt/term
+  signal(SIGINT, myterm);
+  signal(SIGTERM, myterm);
+
+  // Process command-line options and arguments
+  while ((opt = getopt(argc, argv, "d:b:s:e:t:D")) != -1) {
+    switch (opt) {
+    case 'd':
+      capdev = optarg;
+      break;
+    case 'b':
+      bufsize = atof(optarg) * val * 8;
+      if (bufsize < 33280 || bufsize > 1764000) {
+        mylog(LOG_ERR, "Invalid buffer. Range is 0.1-5.0 sec.\n");
+        goto error;
+      }
+      break;
+    case 's':
+      strcpy(startcmd, optarg);
+      if (stat(startcmd, &status) != 0) {
+        mylog(LOG_ERR, "Invalid start command: %s\n", startcmd);
+        goto error;
+      }
+      strcat(startcmd, " &");
+      break;
+    case 'e':
+      strcpy(endcmd, optarg);
+      if (stat(endcmd, &status) != 0) {
+        mylog(LOG_ERR, "Invalid end command: %s\n", endcmd);
+        goto error;
+      }
+      strcat(endcmd, " &");
+      break;
+    case 't':
+      silentt = atoi(optarg);
+      if ((silentt < 1) || (silentt > 32767)) {
+        mylog(LOG_ERR, "Invalid silence threshold. Range is 1-32767.\n");
+        goto error;
+      }
+      break;
+    case 'D':
+      daemonize = 1;
+      break;
+    case '?':
+      err = 1;
+      mylog(LOG_ERR, "Invalid option: %s\n", argv[optind - 1]);
+      break;
+    }
+  }
+  if ((optind + 1) != argc) err = 1;
+  if (err) {
+    if (!daemonize) {
+      printf("\nUsage:\n %s [-d arg] [-b arg] [-s arg] "
+      "[-e arg] [-t arg] [-D] FIFO\n"
+      " -d : ALSA capture device ['default']\n"
+      " -b : target buffer in seconds [.5]\n"
+      " -s : command to run when sound detected\n"
+      " -e : command to run when silence detected\n"
+      " -t : silence threshold (1 - 32767, [100])\n"
+      " -D : daemonize\n"
+      " FIFO : path to a named pipe\n", argv[0]);
+    }
+    goto error;
+  }
+  
+  mylog(LOG_INFO, "Starting up.\n");
+  
+  fifonam = argv[argc - 1];
+
+  // Daemonize
+  if (daemonize) {
+    pid = fork();
+    if (pid < 0) {
+      exit(EXIT_FAILURE);
+    } else if (pid > 0) {
+      exit(EXIT_SUCCESS);
+    }
+    
+    umask(0);
+    
+    sid = setsid();
+    if (sid < 0) {
+      mylog(LOG_ERR, "Error creating new session: %s\n", strerror(errno));
+      goto error;
+    }
+    
+    if (chdir("/") != 0) {
+      mylog(LOG_ERR, "Error on chdir /: %s\n", strerror(errno));
+      goto error;
+    }
+  }
+
+  // Write the pidfile
+  sprintf(pidfile, "/var/run/cpiped.pid");
+  sprintf(pidstr, "%d\n", getpid());
+  pidfd = open(pidfile, O_RDWR|O_CREAT, 0644);
+  write(pidfd, pidstr, strlen(pidstr));
+  close(pidfd);
+  
+  // Open the FIFO for read first, so the open for write succeeds.
+  readfd = open(fifonam, O_RDONLY | O_NONBLOCK);
+  if (readfd <= 0) {
+    mylog(LOG_ERR, "Error opening FIFO for read: %s\n", strerror(errno));
+    goto error;
+  }
+  if (fstat(readfd, &status) != 0) {
+    mylog(LOG_ERR, "fstat error on FIFO (%s).\n", fifonam);
+    goto error;
+  }
+  if (!S_ISFIFO(status.st_mode)) {
+    mylog(LOG_ERR, "%s is not a FIFO.\n", fifonam);
+    goto error;
+  }
+  writefd = open(fifonam, O_WRONLY);
+  if (writefd <= 0) {
+    mylog(LOG_ERR, "Error opening FIFO for write: %s\n", strerror(errno));
+    goto error;
+  }
+  close(readfd);
+  
+  // Set the FIFO size to 8192 bytes to minimize latency
+  fcntl(writefd, F_SETPIPE_SZ, 8192);
+  
+  // Open PCM device for recording (capture).
+  rc = snd_pcm_open(&handle, capdev, SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK);
+  if (rc != 0) {
+    mylog(LOG_ERR, "Unable to open pcm device: %s\n", snd_strerror(rc));
+    goto error;
+  }
+  snd_pcm_hw_params_alloca(&params);
+  snd_pcm_hw_params_any(handle, params);
+  snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);
+  snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);
+  snd_pcm_hw_params_set_channels(handle, params, 2);
+  snd_pcm_hw_params_set_rate_near(handle, params, &val, &dir);
+
+  // Set period size to 1024 frames.
+  frames = 1024;
+  snd_pcm_hw_params_set_period_size_near(handle, params, &frames, &dir);
+
+  // Write the parameters to the driver
+  rc = snd_pcm_hw_params(handle, params);
+  if (rc != 0) {
+    mylog(LOG_ERR, "Unable to set hw parameters: %s\n", snd_strerror(rc));
+    goto error;
+  }
+
+  // Determine the elapsed time of one period
+  snd_pcm_hw_params_get_period_time(params, &capusec, &dir);
+  
+  // Create a capture buffer large enough to hold one period
+  snd_pcm_hw_params_get_period_size(params, &frames, &dir);
+  capsize = frames * 4; // 2 bytes/sample, 2 channels
+  capbuffer = calloc(capsize, sizeof(char));
+  scapbuffer = (int16_t*)capbuffer;
+  
+  // Determine write size
+  writebytes = capsize - 32 ; // Write a bit less to make sure write controls pace
+
+  // Create a ring buffer to handle clock mismatch
+  bufsize++; // Add one byte to permit determination of empty/full states
+  buf = calloc(bufsize, sizeof(char));
+  bufstart = 0;
+  bufend = 0;
+  
+  while (1) { 
+    // Capture samples
+    if (!wrote) // When not writing, wait a bit between captures.
+      usleep(capusec * .95);
+    rc = snd_pcm_readi(handle, capbuffer, frames);
+    if (rc == -EPIPE) { // EPIPE means overrun
+      mylog(LOG_NOTICE, "Overrun occurred\n");
+      snd_pcm_prepare(handle);
+    } else if (rc == -EAGAIN) {
+      rc = 0; // Ignore "Not Available" errors
+    } else if (rc < 0) {
+      mylog(LOG_ERR, "Capture error: %s\n", snd_strerror(rc));
+    }
+ 
+    // Check if there is sound and if so compute RMS power level regularly and count sounds and silences
+    if (capcount > 10 && rc > 0) { // Approx. every quarter second
+      power = 0;
+      for (i = 0; i < rc / 2; i++) {
+        power += pow(scapbuffer[i], 2) + pow(scapbuffer[i + 1], 2);
+      }
+      power = sqrt(power/rc);
+      capcount = 0;
+      
+      if (power > silentt) {
+        soundcount++;
+        silentcount = 0;
+      } else {
+        silentcount++;
+        soundcount = 0;
+      }
+      
+      if (silent && soundcount > 1) {
+        silent = 0;
+        mylog(LOG_INFO, "Sound detected. Last two values: %d, %d\n", prevpower, (int)power);
+        if (strcmp(startcmd, "") != 0) {
+          mylog(LOG_INFO, "Running '%s'\n", startcmd);
+          if (system(startcmd) != 0) {
+            mylog(LOG_ERR, "Error running start command.\n");
+          }
+        }
+      }
+      
+      if (!silent && silentcount > 55) {
+        silent = 1;
+        mylog(LOG_INFO, "Silence detected. Last two values: %d, %d\n", prevpower, (int)power);
+        if (strcmp(endcmd, "") != 0) {
+          mylog(LOG_INFO, "Running '%s'\n", endcmd);
+          if (system(endcmd) != 0) {
+            mylog(LOG_ERR, "Error running end command.\n");
+          }
+        }
+      }
+    }
+    prevpower = power;
+    capcount++;
+  // end of soundcounter   
+  
+  // Check if there is sound, if so write to the pipe
+  if (soundcount > 0) { 
+
+    // Determine the amount of buffer used
+    bufused = bufend - bufstart + (bufend < bufstart) * (bufsize - 1);
+    //printf("size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
+    
+    if (bufused < capsize) {
+      // Buffer is almost empty, don't send to pipe
+      mylog(LOG_INFO, "Filling buffer\n");
+      // nate code
+      mylog(LOG_INFO, "Last two values: %d, %d\n", prevpower, (int)power);
+      fillbuf = 1;
+    }
+    
+    if (bufused > (int)bufsize - 1 - capsize) {
+      // Buffer is almost full, don't store captured samples
+      mylog(LOG_INFO, "Buffer full\n");
+      buffull = 1;
+    }
+
+    // Resume both capture storage and write to pipe when the buffer reaches half-full
+    if ((fillbuf == 1) && (bufused > (int)bufsize / 2))
+      fillbuf = 0;
+    if ((buffull == 1) && (bufused < (int)bufsize / 2))
+      buffull = 0;
+    
+    
+    if (!buffull  && rc > 0) {	
+      // Store samples in buffer
+      readbytes = rc * 4;
+      bufendtoend = bufsize - bufend;
+      if (readbytes <= bufendtoend) {
+        // No wrap required
+        memcpy(buf + bufend, capbuffer, readbytes);
+      } else {
+        // Wrap required
+        memcpy(buf + bufend, capbuffer, bufendtoend);
+        memcpy(buf, capbuffer + bufendtoend, readbytes - bufendtoend);
+      }
+      bufend = (bufend + readbytes) % bufsize;
+    }
+   
+    wrote = 0;
+    if (!fillbuf) {
+      bufstarttoend = bufsize - bufstart;
+      if (writebytes <= bufstarttoend) { // No wrap required
+        rc = write(writefd, buf + bufstart, writebytes);
+        if (rc == writebytes) wrote = 1;
+      } else { // Wrap required
+        rc = write(writefd, buf + bufstart, bufstarttoend);
+        rc = write(writefd, buf, writebytes - bufstarttoend);
+        if (rc == writebytes - bufstarttoend) wrote = 1;
+      }
+      if (wrote) {
+        bufstart = (bufstart + writebytes) % bufsize;
+      } else {
+        bufstart = (bufstart + readbytes) % bufsize; // Keep buffer used constant
+      }
+    }
+  } // end if
+ }
+  exit(EXIT_SUCCESS);
+  
+error:
+  if (readfd > 0) close(readfd);
+  if (writefd > 0) close(writefd);
+  mylog(LOG_INFO, "Stopping due to error.");
+  exit(EXIT_FAILURE);
+}

From f1f8c1c9cc29a7c2d0ad1191a908820baddd28ec Mon Sep 17 00:00:00 2001
From: natedreger <45026176+natedreger@users.noreply.github.com>
Date: Mon, 27 Apr 2020 12:30:00 -0500
Subject: [PATCH 06/26] Update README.md

---
 README.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/README.md b/README.md
index 8f8f737..2136aba 100644
--- a/README.md
+++ b/README.md
@@ -5,3 +5,5 @@ to run a command on detection.
 I'm using this to capture line-in audio from a sound card and send it to 
 forked-daapd (https://github.com/ejurgensen/forked-daapd). On sound detection, it
 runs a simple script to start playing the associated pipe in forked-daapd.
+
+NDpiped builds on cpiped but modifies code such that the buffer is only written if there is sound.  Otherwise I found buffer was constantly writing and Forked-Daapd was playing silence rather then my playlist.

From d7230106eb65ab6f57503e8d2364b9767d9efe89 Mon Sep 17 00:00:00 2001
From: natedreger <45026176+natedreger@users.noreply.github.com>
Date: Mon, 27 Apr 2020 12:39:19 -0500
Subject: [PATCH 07/26] Update README.md

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 2136aba..8f00049 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-cpiped captures an audio stream and outputs it to a pipe with a bit of buffering
+cpiped (https://github.com/b-fitzpatrick/cpiped) captures an audio stream and outputs it to a pipe with a bit of buffering
 to handle clock mismatch. It also includes silence/sound detection and the ability
 to run a command on detection.
 

From 6ec44c5c9b9a02aee61f92f85062d8218d4c0bbb Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 12 Oct 2025 14:32:29 +0200
Subject: [PATCH 08/26] aligned NDpiped and cpiped

---
 NDpiped.c | 402 ------------------------------------------------------
 README.md |   3 +-
 cpiped.c  |  95 +++++++------
 3 files changed, 52 insertions(+), 448 deletions(-)
 delete mode 100644 NDpiped.c

diff --git a/NDpiped.c b/NDpiped.c
deleted file mode 100644
index a87e8c5..0000000
--- a/NDpiped.c
+++ /dev/null
@@ -1,402 +0,0 @@
-/*
- * Original cpiped.c code Copyright (C) 2014 Brian Fitzpatrick <brian@froxen.com>
- * 
- * Modifications 2020 Nate Dreger <info@natedreger.com>
- * 
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#define _GNU_SOURCE
-
-// Use the newer ALSA API
-#define ALSA_PCM_NEW_HW_PARAMS_API
-
-#include <stdio.h>
-#include <math.h>
-#include <alsa/asoundlib.h>
-#include <signal.h>
-#include <sys/stat.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <syslog.h>
-#include <errno.h>
-
-snd_pcm_t *handle;
-int daemonize = 0;
-int readfd = 0;
-int writefd = 0;
-
-void mylog(int level, const char *format, ...)
-{
-    va_list args;
-    va_start (args, format);
-
-    if (daemonize) {
-        vsyslog(level, format, args);
-    } else {
-    vprintf(format, args);
-    }
-    va_end(args);
-}
-
-void myterm() {
-  mylog(LOG_INFO, "Stopping due to interrupt/term.\n");
-  snd_pcm_drain(handle);
-  snd_pcm_close(handle);
-  if (readfd > 0) close(readfd);
-  if (writefd > 0) close(writefd);
-  exit(EXIT_SUCCESS);
-}
-
-int main(int argc, char *argv[]) {
-  int rc;
-  int capsize;
-  snd_pcm_hw_params_t *params;
-  unsigned int val = 44100;
-  unsigned int capusec;
-  int dir;
-  snd_pcm_uframes_t frames;
-  char *capbuffer;
-  int16_t *scapbuffer;
-  char *capdev = "default";
-  char *fifonam;
-  struct stat status;
-  int readbytes = 0;
-  int writebytes = 0;
-  char *buf;
-  size_t bufsize = 176400;
-  int bufstart;
-  int bufend;
-  int bufused;
-  int fillbuf = 1;
-  int buffull = 0;
-  int bufendtoend;
-  int bufstarttoend;
-  int capcount = 0;
-  long power = 0;
-  int prevpower = 0;
-  int i;
-  int silent = 1;
-  int silentcount = 0;
-  int soundcount = 0;
-  char startcmd[1000] = "";
-  char endcmd[1000] = "";
-  int wrote = 0;
-  int silentt = 100;
-  
-  extern char *optarg;
-  extern int optind;
-  int opt;
-  int err = 0;
-  
-  pid_t pid, sid;
-  char pidstr[10];
-  char pidfile[50];
-  int pidfd;
-
-  // Ignore pipe signals
-  signal(SIGPIPE, SIG_IGN);
-  // Flush the hardware buffer on interrupt/term
-  signal(SIGINT, myterm);
-  signal(SIGTERM, myterm);
-
-  // Process command-line options and arguments
-  while ((opt = getopt(argc, argv, "d:b:s:e:t:D")) != -1) {
-    switch (opt) {
-    case 'd':
-      capdev = optarg;
-      break;
-    case 'b':
-      bufsize = atof(optarg) * val * 8;
-      if (bufsize < 33280 || bufsize > 1764000) {
-        mylog(LOG_ERR, "Invalid buffer. Range is 0.1-5.0 sec.\n");
-        goto error;
-      }
-      break;
-    case 's':
-      strcpy(startcmd, optarg);
-      if (stat(startcmd, &status) != 0) {
-        mylog(LOG_ERR, "Invalid start command: %s\n", startcmd);
-        goto error;
-      }
-      strcat(startcmd, " &");
-      break;
-    case 'e':
-      strcpy(endcmd, optarg);
-      if (stat(endcmd, &status) != 0) {
-        mylog(LOG_ERR, "Invalid end command: %s\n", endcmd);
-        goto error;
-      }
-      strcat(endcmd, " &");
-      break;
-    case 't':
-      silentt = atoi(optarg);
-      if ((silentt < 1) || (silentt > 32767)) {
-        mylog(LOG_ERR, "Invalid silence threshold. Range is 1-32767.\n");
-        goto error;
-      }
-      break;
-    case 'D':
-      daemonize = 1;
-      break;
-    case '?':
-      err = 1;
-      mylog(LOG_ERR, "Invalid option: %s\n", argv[optind - 1]);
-      break;
-    }
-  }
-  if ((optind + 1) != argc) err = 1;
-  if (err) {
-    if (!daemonize) {
-      printf("\nUsage:\n %s [-d arg] [-b arg] [-s arg] "
-      "[-e arg] [-t arg] [-D] FIFO\n"
-      " -d : ALSA capture device ['default']\n"
-      " -b : target buffer in seconds [.5]\n"
-      " -s : command to run when sound detected\n"
-      " -e : command to run when silence detected\n"
-      " -t : silence threshold (1 - 32767, [100])\n"
-      " -D : daemonize\n"
-      " FIFO : path to a named pipe\n", argv[0]);
-    }
-    goto error;
-  }
-  
-  mylog(LOG_INFO, "Starting up.\n");
-  
-  fifonam = argv[argc - 1];
-
-  // Daemonize
-  if (daemonize) {
-    pid = fork();
-    if (pid < 0) {
-      exit(EXIT_FAILURE);
-    } else if (pid > 0) {
-      exit(EXIT_SUCCESS);
-    }
-    
-    umask(0);
-    
-    sid = setsid();
-    if (sid < 0) {
-      mylog(LOG_ERR, "Error creating new session: %s\n", strerror(errno));
-      goto error;
-    }
-    
-    if (chdir("/") != 0) {
-      mylog(LOG_ERR, "Error on chdir /: %s\n", strerror(errno));
-      goto error;
-    }
-  }
-
-  // Write the pidfile
-  sprintf(pidfile, "/var/run/cpiped.pid");
-  sprintf(pidstr, "%d\n", getpid());
-  pidfd = open(pidfile, O_RDWR|O_CREAT, 0644);
-  write(pidfd, pidstr, strlen(pidstr));
-  close(pidfd);
-  
-  // Open the FIFO for read first, so the open for write succeeds.
-  readfd = open(fifonam, O_RDONLY | O_NONBLOCK);
-  if (readfd <= 0) {
-    mylog(LOG_ERR, "Error opening FIFO for read: %s\n", strerror(errno));
-    goto error;
-  }
-  if (fstat(readfd, &status) != 0) {
-    mylog(LOG_ERR, "fstat error on FIFO (%s).\n", fifonam);
-    goto error;
-  }
-  if (!S_ISFIFO(status.st_mode)) {
-    mylog(LOG_ERR, "%s is not a FIFO.\n", fifonam);
-    goto error;
-  }
-  writefd = open(fifonam, O_WRONLY);
-  if (writefd <= 0) {
-    mylog(LOG_ERR, "Error opening FIFO for write: %s\n", strerror(errno));
-    goto error;
-  }
-  close(readfd);
-  
-  // Set the FIFO size to 8192 bytes to minimize latency
-  fcntl(writefd, F_SETPIPE_SZ, 8192);
-  
-  // Open PCM device for recording (capture).
-  rc = snd_pcm_open(&handle, capdev, SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK);
-  if (rc != 0) {
-    mylog(LOG_ERR, "Unable to open pcm device: %s\n", snd_strerror(rc));
-    goto error;
-  }
-  snd_pcm_hw_params_alloca(&params);
-  snd_pcm_hw_params_any(handle, params);
-  snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);
-  snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);
-  snd_pcm_hw_params_set_channels(handle, params, 2);
-  snd_pcm_hw_params_set_rate_near(handle, params, &val, &dir);
-
-  // Set period size to 1024 frames.
-  frames = 1024;
-  snd_pcm_hw_params_set_period_size_near(handle, params, &frames, &dir);
-
-  // Write the parameters to the driver
-  rc = snd_pcm_hw_params(handle, params);
-  if (rc != 0) {
-    mylog(LOG_ERR, "Unable to set hw parameters: %s\n", snd_strerror(rc));
-    goto error;
-  }
-
-  // Determine the elapsed time of one period
-  snd_pcm_hw_params_get_period_time(params, &capusec, &dir);
-  
-  // Create a capture buffer large enough to hold one period
-  snd_pcm_hw_params_get_period_size(params, &frames, &dir);
-  capsize = frames * 4; // 2 bytes/sample, 2 channels
-  capbuffer = calloc(capsize, sizeof(char));
-  scapbuffer = (int16_t*)capbuffer;
-  
-  // Determine write size
-  writebytes = capsize - 32 ; // Write a bit less to make sure write controls pace
-
-  // Create a ring buffer to handle clock mismatch
-  bufsize++; // Add one byte to permit determination of empty/full states
-  buf = calloc(bufsize, sizeof(char));
-  bufstart = 0;
-  bufend = 0;
-  
-  while (1) { 
-    // Capture samples
-    if (!wrote) // When not writing, wait a bit between captures.
-      usleep(capusec * .95);
-    rc = snd_pcm_readi(handle, capbuffer, frames);
-    if (rc == -EPIPE) { // EPIPE means overrun
-      mylog(LOG_NOTICE, "Overrun occurred\n");
-      snd_pcm_prepare(handle);
-    } else if (rc == -EAGAIN) {
-      rc = 0; // Ignore "Not Available" errors
-    } else if (rc < 0) {
-      mylog(LOG_ERR, "Capture error: %s\n", snd_strerror(rc));
-    }
- 
-    // Check if there is sound and if so compute RMS power level regularly and count sounds and silences
-    if (capcount > 10 && rc > 0) { // Approx. every quarter second
-      power = 0;
-      for (i = 0; i < rc / 2; i++) {
-        power += pow(scapbuffer[i], 2) + pow(scapbuffer[i + 1], 2);
-      }
-      power = sqrt(power/rc);
-      capcount = 0;
-      
-      if (power > silentt) {
-        soundcount++;
-        silentcount = 0;
-      } else {
-        silentcount++;
-        soundcount = 0;
-      }
-      
-      if (silent && soundcount > 1) {
-        silent = 0;
-        mylog(LOG_INFO, "Sound detected. Last two values: %d, %d\n", prevpower, (int)power);
-        if (strcmp(startcmd, "") != 0) {
-          mylog(LOG_INFO, "Running '%s'\n", startcmd);
-          if (system(startcmd) != 0) {
-            mylog(LOG_ERR, "Error running start command.\n");
-          }
-        }
-      }
-      
-      if (!silent && silentcount > 55) {
-        silent = 1;
-        mylog(LOG_INFO, "Silence detected. Last two values: %d, %d\n", prevpower, (int)power);
-        if (strcmp(endcmd, "") != 0) {
-          mylog(LOG_INFO, "Running '%s'\n", endcmd);
-          if (system(endcmd) != 0) {
-            mylog(LOG_ERR, "Error running end command.\n");
-          }
-        }
-      }
-    }
-    prevpower = power;
-    capcount++;
-  // end of soundcounter   
-  
-  // Check if there is sound, if so write to the pipe
-  if (soundcount > 0) { 
-
-    // Determine the amount of buffer used
-    bufused = bufend - bufstart + (bufend < bufstart) * (bufsize - 1);
-    //printf("size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
-    
-    if (bufused < capsize) {
-      // Buffer is almost empty, don't send to pipe
-      mylog(LOG_INFO, "Filling buffer\n");
-      // nate code
-      mylog(LOG_INFO, "Last two values: %d, %d\n", prevpower, (int)power);
-      fillbuf = 1;
-    }
-    
-    if (bufused > (int)bufsize - 1 - capsize) {
-      // Buffer is almost full, don't store captured samples
-      mylog(LOG_INFO, "Buffer full\n");
-      buffull = 1;
-    }
-
-    // Resume both capture storage and write to pipe when the buffer reaches half-full
-    if ((fillbuf == 1) && (bufused > (int)bufsize / 2))
-      fillbuf = 0;
-    if ((buffull == 1) && (bufused < (int)bufsize / 2))
-      buffull = 0;
-    
-    
-    if (!buffull  && rc > 0) {	
-      // Store samples in buffer
-      readbytes = rc * 4;
-      bufendtoend = bufsize - bufend;
-      if (readbytes <= bufendtoend) {
-        // No wrap required
-        memcpy(buf + bufend, capbuffer, readbytes);
-      } else {
-        // Wrap required
-        memcpy(buf + bufend, capbuffer, bufendtoend);
-        memcpy(buf, capbuffer + bufendtoend, readbytes - bufendtoend);
-      }
-      bufend = (bufend + readbytes) % bufsize;
-    }
-   
-    wrote = 0;
-    if (!fillbuf) {
-      bufstarttoend = bufsize - bufstart;
-      if (writebytes <= bufstarttoend) { // No wrap required
-        rc = write(writefd, buf + bufstart, writebytes);
-        if (rc == writebytes) wrote = 1;
-      } else { // Wrap required
-        rc = write(writefd, buf + bufstart, bufstarttoend);
-        rc = write(writefd, buf, writebytes - bufstarttoend);
-        if (rc == writebytes - bufstarttoend) wrote = 1;
-      }
-      if (wrote) {
-        bufstart = (bufstart + writebytes) % bufsize;
-      } else {
-        bufstart = (bufstart + readbytes) % bufsize; // Keep buffer used constant
-      }
-    }
-  } // end if
- }
-  exit(EXIT_SUCCESS);
-  
-error:
-  if (readfd > 0) close(readfd);
-  if (writefd > 0) close(writefd);
-  mylog(LOG_INFO, "Stopping due to error.");
-  exit(EXIT_FAILURE);
-}
diff --git a/README.md b/README.md
index 8f00049..adf9711 100644
--- a/README.md
+++ b/README.md
@@ -6,4 +6,5 @@ I'm using this to capture line-in audio from a sound card and send it to
 forked-daapd (https://github.com/ejurgensen/forked-daapd). On sound detection, it
 runs a simple script to start playing the associated pipe in forked-daapd.
 
-NDpiped builds on cpiped but modifies code such that the buffer is only written if there is sound.  Otherwise I found buffer was constantly writing and Forked-Daapd was playing silence rather then my playlist.
+#### Merged work
+- NDpiped builds on cpiped but modifies code such that the buffer is only written if there is sound.  Otherwise I found buffer was constantly writing and Forked-Daapd was playing silence rather then my playlist. (https://github.com/natedreger/cpiped) and (https://github.com/natedreger/NDpiped)
diff --git a/cpiped.c b/cpiped.c
index ff77298..c5f1467 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -111,12 +111,12 @@ int main(int argc, char *argv[]) {
   char endcmd[1000] = "";
   int wrote = 0;
   int silentt = 100;
-  
+
   extern char *optarg;
   extern int optind;
   int opt;
   int err = 0;
-  
+
   pid_t pid, sid;
   char pidstr[10];
   char pidfile[50];
@@ -192,9 +192,9 @@ int main(int argc, char *argv[]) {
     }
     goto error;
   }
-  
+
   mylog(LOG_INFO, "Starting up.\n");
-  
+
   fifonam = argv[argc - 1];
 
   // Daemonize
@@ -205,15 +205,15 @@ int main(int argc, char *argv[]) {
     } else if (pid > 0) {
       exit(EXIT_SUCCESS);
     }
-    
+
     umask(0);
-    
+
     sid = setsid();
     if (sid < 0) {
       mylog(LOG_ERR, "Error creating new session: %s\n", strerror(errno));
       goto error;
     }
-    
+
     if (chdir("/") != 0) {
       mylog(LOG_ERR, "Error on chdir /: %s\n", strerror(errno));
       goto error;
@@ -226,7 +226,7 @@ int main(int argc, char *argv[]) {
   pidfd = open(pidfile, O_RDWR|O_CREAT, 0644);
   write(pidfd, pidstr, strlen(pidstr));
   close(pidfd);
-  
+
   // Open the FIFO for read first, so the open for write succeeds.
   readfd = open(fifonam, O_RDONLY | O_NONBLOCK);
   if (readfd <= 0) {
@@ -247,10 +247,10 @@ int main(int argc, char *argv[]) {
     goto error;
   }
   close(readfd);
-  
+
   // Set the FIFO size to 8192 bytes to minimize latency
   fcntl(writefd, F_SETPIPE_SZ, 8192);
-  
+
   // Open PCM device for recording (capture).
   rc = snd_pcm_open(&handle, capdev, SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK);
   if (rc != 0) {
@@ -277,13 +277,13 @@ int main(int argc, char *argv[]) {
 
   // Determine the elapsed time of one period
   snd_pcm_hw_params_get_period_time(params, &capusec, &dir);
-  
+
   // Create a capture buffer large enough to hold one period
   snd_pcm_hw_params_get_period_size(params, &frames, &dir);
   capsize = frames * 4; // 2 bytes/sample, 2 channels
   capbuffer = calloc(capsize, sizeof(char));
   scapbuffer = (int16_t*)capbuffer;
-  
+
   // Determine write size
   writebytes = capsize - 32 ; // Write a bit less to make sure write controls pace
 
@@ -292,30 +292,8 @@ int main(int argc, char *argv[]) {
   buf = calloc(bufsize, sizeof(char));
   bufstart = 0;
   bufend = 0;
-  
-  while (1) {
-    // Determine the amount of buffer used
-    bufused = bufend - bufstart + (bufend < bufstart) * (bufsize - 1);
-    //printf("size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
-    
-    if (bufused < capsize) {
-      // Buffer is almost empty, don't send to pipe
-      mylogverb(LOG_INFO, 1, "Filling buffer\n");
-      fillbuf = 1;
-    }
-    
-    if (bufused > (int)bufsize - 1 - capsize) {
-      // Buffer is almost full, don't store captured samples
-      mylogverb(LOG_INFO, 0, "Buffer full\n");
-      buffull = 1;
-    }
 
-    // Resume both capture storage and write to pipe when the buffer reaches half-full
-    if ((fillbuf == 1) && (bufused > (int)bufsize / 2))
-      fillbuf = 0;
-    if ((buffull == 1) && (bufused < (int)bufsize / 2))
-      buffull = 0;
-    
+  while (1) {
     // Capture samples
     if (!wrote) // When not writing, wait a bit between captures.
       usleep(capusec * .95);
@@ -328,8 +306,8 @@ int main(int argc, char *argv[]) {
     } else if (rc < 0) {
       mylog(LOG_ERR, "Capture error: %s\n", snd_strerror(rc));
     }
-    
-    // Compute RMS power level regularly
+
+    // Check if there is sound and if so compute RMS power level regularly and count sounds and silences
     if (capcount > 10 && rc > 0) { // Approx. every quarter second
       power = 0;
       for (i = 0; i < rc / 2; i++) {
@@ -337,7 +315,7 @@ int main(int argc, char *argv[]) {
       }
       power = sqrt(power/rc);
       capcount = 0;
-      
+
       if (power > silentt) {
         soundcount++;
         silentcount = 0;
@@ -345,7 +323,7 @@ int main(int argc, char *argv[]) {
         silentcount++;
         soundcount = 0;
       }
-      
+
       if (silent && soundcount > 1) {
         silent = 0;
         mylogverb(LOG_INFO, 0, "Sound detected. Last two values: %d, %d\n", prevpower, (int)power);
@@ -356,7 +334,7 @@ int main(int argc, char *argv[]) {
           }
         }
       }
-      
+
       if (!silent && silentcount > 55) {
         silent = 1;
         mylogverb(LOG_INFO, 0, "Silence detected. Last two values: %d, %d\n", prevpower, (int)power);
@@ -370,8 +348,34 @@ int main(int argc, char *argv[]) {
     }
     prevpower = power;
     capcount++;
-      
-    if (!buffull  && rc > 0) {	
+  // end of soundcounter
+
+  // Check if there is sound, if so write to the pipe
+  if (soundcount > 0) {
+
+    // Determine the amount of buffer used
+    bufused = bufend - bufstart + (bufend < bufstart) * (bufsize - 1);
+    //printf("size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
+
+    if (bufused < capsize) {
+      // Buffer is almost empty, don't send to pipe
+      mylogverb(LOG_INFO, 1, "Filling buffer\n");
+      fillbuf = 1;
+    }
+
+    if (bufused > (int)bufsize - 1 - capsize) {
+      // Buffer is almost full, don't store captured samples
+      mylogverb(LOG_INFO, 0, "Buffer full\n");
+      buffull = 1;
+    }
+
+    // Resume both capture storage and write to pipe when the buffer reaches half-full
+    if ((fillbuf == 1) && (bufused > (int)bufsize / 2))
+      fillbuf = 0;
+    if ((buffull == 1) && (bufused < (int)bufsize / 2))
+      buffull = 0;
+
+    if (!buffull  && rc > 0) {
       // Store samples in buffer
       readbytes = rc * 4;
       bufendtoend = bufsize - bufend;
@@ -385,7 +389,7 @@ int main(int argc, char *argv[]) {
       }
       bufend = (bufend + readbytes) % bufsize;
     }
-    
+
     wrote = 0;
     if (!fillbuf) {
       bufstarttoend = bufsize - bufstart;
@@ -403,9 +407,10 @@ int main(int argc, char *argv[]) {
         bufstart = (bufstart + readbytes) % bufsize; // Keep buffer used constant
       }
     }
-  }
+  } // end if
+ }
   exit(EXIT_SUCCESS);
-  
+
 error:
   if (readfd > 0) close(readfd);
   if (writefd > 0) close(writefd);

From 4da6f1bb53a93ffd754b7f1a90fce638c19323b2 Mon Sep 17 00:00:00 2001
From: Mario Wenzel <maweki@gmail.com>
Date: Tue, 7 Jan 2020 20:56:12 +0100
Subject: [PATCH 09/26] parameterize pid

---
 cpiped.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index c5f1467..67f4136 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -87,6 +87,7 @@ int main(int argc, char *argv[]) {
   char *capbuffer;
   int16_t *scapbuffer;
   char *capdev = "default";
+  char *pidpath = "/var/run/cpiped.pid";
   char *fifonam;
   struct stat status;
   int readbytes = 0;
@@ -129,7 +130,7 @@ int main(int argc, char *argv[]) {
   signal(SIGTERM, myterm);
 
   // Process command-line options and arguments
-  while ((opt = getopt(argc, argv, "d:b:s:e:t:Dv")) != -1) {
+  while ((opt = getopt(argc, argv, "d:b:s:e:t:Dp:v")) != -1) {
     switch (opt) {
     case 'd':
       capdev = optarg;
@@ -167,6 +168,9 @@ int main(int argc, char *argv[]) {
     case 'D':
       daemonize = 1;
       break;
+    case 'p':
+      pidpath = optarg;
+      break;
     case 'v':
       log_verb = 1;
       break;
@@ -187,6 +191,7 @@ int main(int argc, char *argv[]) {
       " -e : command to run when silence detected\n"
       " -t : silence threshold (1 - 32767, [100])\n"
       " -D : daemonize\n"
+      " -p : path to pidfile [/var/run/cpiped.pid]\n"
       " -v : enable more verbose logs\n"
       " FIFO : path to a named pipe\n", argv[0]);
     }
@@ -221,7 +226,7 @@ int main(int argc, char *argv[]) {
   }
 
   // Write the pidfile
-  sprintf(pidfile, "/var/run/cpiped.pid");
+  sprintf(pidfile, pidpath);
   sprintf(pidstr, "%d\n", getpid());
   pidfd = open(pidfile, O_RDWR|O_CREAT, 0644);
   write(pidfd, pidstr, strlen(pidstr));

From b8e44229e1ec667974cca844a9ccdb5d36b7e0b6 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 12 Oct 2025 15:10:00 +0200
Subject: [PATCH 10/26] README update

---
 README.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/README.md b/README.md
index adf9711..9721f5e 100644
--- a/README.md
+++ b/README.md
@@ -8,3 +8,4 @@ runs a simple script to start playing the associated pipe in forked-daapd.
 
 #### Merged work
 - NDpiped builds on cpiped but modifies code such that the buffer is only written if there is sound.  Otherwise I found buffer was constantly writing and Forked-Daapd was playing silence rather then my playlist. (https://github.com/natedreger/cpiped) and (https://github.com/natedreger/NDpiped)
+- Parametrized pid file by Mario Wenzel (https://github.com/maweki/cpiped)
\ No newline at end of file

From b11c922c6c675418c6c7ecf35c2cf8e32613869e Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 12 Oct 2025 15:10:51 +0200
Subject: [PATCH 11/26] README update with ToDo list

---
 README.md | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 9721f5e..9a0f1fd 100644
--- a/README.md
+++ b/README.md
@@ -8,4 +8,8 @@ runs a simple script to start playing the associated pipe in forked-daapd.
 
 #### Merged work
 - NDpiped builds on cpiped but modifies code such that the buffer is only written if there is sound.  Otherwise I found buffer was constantly writing and Forked-Daapd was playing silence rather then my playlist. (https://github.com/natedreger/cpiped) and (https://github.com/natedreger/NDpiped)
-- Parametrized pid file by Mario Wenzel (https://github.com/maweki/cpiped)
\ No newline at end of file
+- Parametrized pid file by Mario Wenzel (https://github.com/maweki/cpiped)
+
+#### ToDo(s)
+- [ ] Improve Makefile to create dedicated build folder
+- [ ] Improve Makefile to add install directive
\ No newline at end of file

From 3f7027b5c079a8ebfd57d465e81aef68d2aa515e Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sat, 25 Oct 2025 12:05:36 +0200
Subject: [PATCH 12/26] introduced variables for sample size and channel count

- refactored val variable to samplerate
- made buffer and capture sizes calculation function of samplerate and captured channels count
---
 cpiped.c | 128 ++++++++++++++++++++++++++++---------------------------
 1 file changed, 65 insertions(+), 63 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 67f4136..59cec34 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -80,7 +80,9 @@ int main(int argc, char *argv[]) {
   int rc;
   int capsize;
   snd_pcm_hw_params_t *params;
-  unsigned int val = 44100;
+  unsigned int samplerate = 41000;
+  unsigned int samplesize = 16;
+  unsigned int capchannels = 2;
   unsigned int capusec;
   int dir;
   snd_pcm_uframes_t frames;
@@ -136,7 +138,7 @@ int main(int argc, char *argv[]) {
       capdev = optarg;
       break;
     case 'b':
-      bufsize = atof(optarg) * val * 8;
+      bufsize = atof(optarg) * samplerate * 8;
       if (bufsize < 33280 || bufsize > 1764000) {
         mylog(LOG_ERR, "Invalid buffer. Range is 0.1-5.0 sec.\n");
         goto error;
@@ -266,8 +268,8 @@ int main(int argc, char *argv[]) {
   snd_pcm_hw_params_any(handle, params);
   snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);
   snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);
-  snd_pcm_hw_params_set_channels(handle, params, 2);
-  snd_pcm_hw_params_set_rate_near(handle, params, &val, &dir);
+  snd_pcm_hw_params_set_channels(handle, params, capchannels);
+  snd_pcm_hw_params_set_rate_near(handle, params, &samplerate, &dir);
 
   // Set period size to 1024 frames.
   frames = 1024;
@@ -285,7 +287,7 @@ int main(int argc, char *argv[]) {
 
   // Create a capture buffer large enough to hold one period
   snd_pcm_hw_params_get_period_size(params, &frames, &dir);
-  capsize = frames * 4; // 2 bytes/sample, 2 channels
+  capsize = frames * (samplesize / 8) * capchannels; // (<samplesize> / 8) bytes/sample * <capchannels> channels
   capbuffer = calloc(capsize, sizeof(char));
   scapbuffer = (int16_t*)capbuffer;
 
@@ -353,72 +355,72 @@ int main(int argc, char *argv[]) {
     }
     prevpower = power;
     capcount++;
-  // end of soundcounter
+    // end of soundcounter
 
-  // Check if there is sound, if so write to the pipe
-  if (soundcount > 0) {
+    // Check if there is sound, if so write to the pipe
+    if (soundcount > 0) {
 
-    // Determine the amount of buffer used
-    bufused = bufend - bufstart + (bufend < bufstart) * (bufsize - 1);
-    //printf("size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
+      // Determine the amount of buffer used
+      bufused = bufend - bufstart + (bufend < bufstart) * (bufsize - 1);
+      //printf("size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
 
-    if (bufused < capsize) {
-      // Buffer is almost empty, don't send to pipe
-      mylogverb(LOG_INFO, 1, "Filling buffer\n");
-      fillbuf = 1;
-    }
-
-    if (bufused > (int)bufsize - 1 - capsize) {
-      // Buffer is almost full, don't store captured samples
-      mylogverb(LOG_INFO, 0, "Buffer full\n");
-      buffull = 1;
-    }
+      if (bufused < capsize) {
+        // Buffer is almost empty, don't send to pipe
+        mylogverb(LOG_INFO, 1, "Filling buffer\n");
+        fillbuf = 1;
+      }
 
-    // Resume both capture storage and write to pipe when the buffer reaches half-full
-    if ((fillbuf == 1) && (bufused > (int)bufsize / 2))
-      fillbuf = 0;
-    if ((buffull == 1) && (bufused < (int)bufsize / 2))
-      buffull = 0;
-
-    if (!buffull  && rc > 0) {
-      // Store samples in buffer
-      readbytes = rc * 4;
-      bufendtoend = bufsize - bufend;
-      if (readbytes <= bufendtoend) {
-        // No wrap required
-        memcpy(buf + bufend, capbuffer, readbytes);
-      } else {
-        // Wrap required
-        memcpy(buf + bufend, capbuffer, bufendtoend);
-        memcpy(buf, capbuffer + bufendtoend, readbytes - bufendtoend);
+      if (bufused > (int)bufsize - 1 - capsize) {
+        // Buffer is almost full, don't store captured samples
+        mylogverb(LOG_INFO, 0, "Buffer full\n");
+        buffull = 1;
       }
-      bufend = (bufend + readbytes) % bufsize;
-    }
 
-    wrote = 0;
-    if (!fillbuf) {
-      bufstarttoend = bufsize - bufstart;
-      if (writebytes <= bufstarttoend) { // No wrap required
-        rc = write(writefd, buf + bufstart, writebytes);
-        if (rc == writebytes) wrote = 1;
-      } else { // Wrap required
-        rc = write(writefd, buf + bufstart, bufstarttoend);
-        rc = write(writefd, buf, writebytes - bufstarttoend);
-        if (rc == writebytes - bufstarttoend) wrote = 1;
+      // Resume both capture storage and write to pipe when the buffer reaches half-full
+      if ((fillbuf == 1) && (bufused > (int)bufsize / 2))
+        fillbuf = 0;
+      if ((buffull == 1) && (bufused < (int)bufsize / 2))
+        buffull = 0;
+
+      if (!buffull  && rc > 0) {
+        // Store samples in buffer
+        readbytes = rc * 4;
+        bufendtoend = bufsize - bufend;
+        if (readbytes <= bufendtoend) {
+          // No wrap required
+          memcpy(buf + bufend, capbuffer, readbytes);
+        } else {
+          // Wrap required
+          memcpy(buf + bufend, capbuffer, bufendtoend);
+          memcpy(buf, capbuffer + bufendtoend, readbytes - bufendtoend);
+        }
+        bufend = (bufend + readbytes) % bufsize;
       }
-      if (wrote) {
-        bufstart = (bufstart + writebytes) % bufsize;
-      } else {
-        bufstart = (bufstart + readbytes) % bufsize; // Keep buffer used constant
+
+      wrote = 0;
+      if (!fillbuf) {
+        bufstarttoend = bufsize - bufstart;
+        if (writebytes <= bufstarttoend) { // No wrap required
+          rc = write(writefd, buf + bufstart, writebytes);
+          if (rc == writebytes) wrote = 1;
+        } else { // Wrap required
+          rc = write(writefd, buf + bufstart, bufstarttoend);
+          rc = write(writefd, buf, writebytes - bufstarttoend);
+          if (rc == writebytes - bufstarttoend) wrote = 1;
+        }
+        if (wrote) {
+          bufstart = (bufstart + writebytes) % bufsize;
+        } else {
+          bufstart = (bufstart + readbytes) % bufsize; // Keep buffer used constant
+        }
       }
-    }
-  } // end if
- }
+    } // end if
+  }
   exit(EXIT_SUCCESS);
 
-error:
-  if (readfd > 0) close(readfd);
-  if (writefd > 0) close(writefd);
-  mylog(LOG_INFO, "Stopping due to error.");
-  exit(EXIT_FAILURE);
+  error:
+    if (readfd > 0) close(readfd);
+    if (writefd > 0) close(writefd);
+    mylog(LOG_INFO, "Stopping due to error.");
+    exit(EXIT_FAILURE);
 }

From dab9dcbb48d962208ac77db4b4fcd359f3a57087 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sat, 25 Oct 2025 12:42:35 +0200
Subject: [PATCH 13/26] made bufsize truly reliant on buffer duration, sample
 rate and capture channels

---
 cpiped.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 59cec34..7dd7764 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -95,7 +95,8 @@ int main(int argc, char *argv[]) {
   int readbytes = 0;
   int writebytes = 0;
   char *buf;
-  size_t bufsize = 176400;
+  size_t bufsize = 0;
+  float bufdur = 0.25;
   int bufstart;
   int bufend;
   int bufused;
@@ -138,8 +139,8 @@ int main(int argc, char *argv[]) {
       capdev = optarg;
       break;
     case 'b':
-      bufsize = atof(optarg) * samplerate * 8;
-      if (bufsize < 33280 || bufsize > 1764000) {
+      bufdur = atof(optarg);
+      if (bufdur < 0.1 || bufdur > 5.0) {
         mylog(LOG_ERR, "Invalid buffer. Range is 0.1-5.0 sec.\n");
         goto error;
       }
@@ -271,6 +272,9 @@ int main(int argc, char *argv[]) {
   snd_pcm_hw_params_set_channels(handle, params, capchannels);
   snd_pcm_hw_params_set_rate_near(handle, params, &samplerate, &dir);
 
+  // set buffer size in bit
+  bufsize = bufdur * samplerate * capchannels * 8;
+
   // Set period size to 1024 frames.
   frames = 1024;
   snd_pcm_hw_params_set_period_size_near(handle, params, &frames, &dir);

From 6ea4e4bb301167c203071ab9e6993820ff35c900 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sat, 25 Oct 2025 16:19:43 +0200
Subject: [PATCH 14/26] linked size of readbuffer to sample size and captured
 channels

---
 cpiped.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 7dd7764..64750b6 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -366,7 +366,7 @@ int main(int argc, char *argv[]) {
 
       // Determine the amount of buffer used
       bufused = bufend - bufstart + (bufend < bufstart) * (bufsize - 1);
-      //printf("size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
+      mylogverb(LOG_INFO, 3, "size:%d, start:%d, end:%d, used:%d, wrote:%d\n", bufsize, bufstart, bufend, bufused, wrote);
 
       if (bufused < capsize) {
         // Buffer is almost empty, don't send to pipe
@@ -388,7 +388,7 @@ int main(int argc, char *argv[]) {
 
       if (!buffull  && rc > 0) {
         // Store samples in buffer
-        readbytes = rc * 4;
+        readbytes = rc * (samplesize / 8) * capchannels;
         bufendtoend = bufsize - bufend;
         if (readbytes <= bufendtoend) {
           // No wrap required

From 1bcc48012f15eedcd3d9df03f36e4be48f86b9a7 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sat, 25 Oct 2025 17:37:07 +0200
Subject: [PATCH 15/26] added -vv and -vvv options for higher verbosity levels

---
 cpiped.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 64750b6..e4a371f 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -20,16 +20,16 @@
 // Use the newer ALSA API
 #define ALSA_PCM_NEW_HW_PARAMS_API
 
-#include <stdio.h>
-#include <math.h>
 #include <alsa/asoundlib.h>
+#include <errno.h>
+#include <math.h>
 #include <signal.h>
 #include <sys/stat.h>
+#include <syslog.h>
+#include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include <syslog.h>
-#include <errno.h>
 
 snd_pcm_t *handle;
 int daemonize = 0;
@@ -133,7 +133,7 @@ int main(int argc, char *argv[]) {
   signal(SIGTERM, myterm);
 
   // Process command-line options and arguments
-  while ((opt = getopt(argc, argv, "d:b:s:e:t:Dp:v")) != -1) {
+  while ((opt = getopt(argc, argv, "d:b:s:e:t:Dp:v:")) != -1) {
     switch (opt) {
     case 'd':
       capdev = optarg;
@@ -176,6 +176,8 @@ int main(int argc, char *argv[]) {
       break;
     case 'v':
       log_verb = 1;
+      if (strcmp(optarg, "v" ) == 0) {log_verb = 2;}
+      if (strcmp(optarg, "vv") == 0) {log_verb = 3;}
       break;
     case '?':
       err = 1;
@@ -195,7 +197,7 @@ int main(int argc, char *argv[]) {
       " -t : silence threshold (1 - 32767, [100])\n"
       " -D : daemonize\n"
       " -p : path to pidfile [/var/run/cpiped.pid]\n"
-      " -v : enable more verbose logs\n"
+      " -v : enable more verbose logs (-vv and -vvv for higher verbosity levels)\n"
       " FIFO : path to a named pipe\n", argv[0]);
     }
     goto error;

From 0944a931ab073e9df6324f9f6ecc0c05918c3de7 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 2 Nov 2025 19:34:48 +0100
Subject: [PATCH 16/26] cleaned up pid file code

---
 cpiped.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index e4a371f..9a7fdea 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -123,7 +123,6 @@ int main(int argc, char *argv[]) {
 
   pid_t pid, sid;
   char pidstr[10];
-  char pidfile[50];
   int pidfd;
 
   // Ignore pipe signals
@@ -172,7 +171,8 @@ int main(int argc, char *argv[]) {
       daemonize = 1;
       break;
     case 'p':
-      pidpath = optarg;
+      pidpath = calloc(strlen(optarg), sizeof(char));
+      sprintf(pidpath, optarg);
       break;
     case 'v':
       log_verb = 1;
@@ -231,9 +231,8 @@ int main(int argc, char *argv[]) {
   }
 
   // Write the pidfile
-  sprintf(pidfile, pidpath);
   sprintf(pidstr, "%d\n", getpid());
-  pidfd = open(pidfile, O_RDWR|O_CREAT, 0644);
+  pidfd = open(pidpath, O_RDWR|O_CREAT, 0644);
   write(pidfd, pidstr, strlen(pidstr));
   close(pidfd);
 

From abe9841296d40ef29568c564591424f517a1318d Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 2 Nov 2025 19:37:44 +0100
Subject: [PATCH 17/26] added -f command line parameter to set sample frequency

- cleaned up help message in case of error
---
 cpiped.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 9a7fdea..fc32b8e 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -132,7 +132,7 @@ int main(int argc, char *argv[]) {
   signal(SIGTERM, myterm);
 
   // Process command-line options and arguments
-  while ((opt = getopt(argc, argv, "d:b:s:e:t:Dp:v:")) != -1) {
+  while ((opt = getopt(argc, argv, "d:b:s:e:f:t:Dp:v:")) != -1) {
     switch (opt) {
     case 'd':
       capdev = optarg;
@@ -167,6 +167,13 @@ int main(int argc, char *argv[]) {
         goto error;
       }
       break;
+    case 'f':
+      samplerate = atoi(optarg);
+      if ((samplerate < 16000) || (samplerate > 192000)) {
+        mylog(LOG_ERR, "Invalid sample rate. Range is 16000-192000.\n");
+        goto error;
+      }
+      break;
     case 'D':
       daemonize = 1;
       break;
@@ -188,19 +195,19 @@ int main(int argc, char *argv[]) {
   if ((optind + 1) != argc) err = 1;
   if (err) {
     if (!daemonize) {
-      printf("\nUsage:\n %s [-d arg] [-b arg] [-s arg] "
-      "[-e arg] [-t arg] [-D] FIFO\n"
+      printf("\nUsage:\n %s [-s arg] [-e arg] [OPTIONS] FIFO\n"
       " -d : ALSA capture device ['default']\n"
-      " -b : target buffer in seconds [.5]\n"
+      " -b : target buffer in seconds [.25]\n"
       " -s : command to run when sound detected\n"
       " -e : command to run when silence detected\n"
       " -t : silence threshold (1 - 32767, [100])\n"
+      " -f : sample rate (16000 - 192000, [44100])\n"
       " -D : daemonize\n"
       " -p : path to pidfile [/var/run/cpiped.pid]\n"
       " -v : enable more verbose logs (-vv and -vvv for higher verbosity levels)\n"
       " FIFO : path to a named pipe\n", argv[0]);
     }
-    goto error;
+    exit(EXIT_FAILURE);
   }
 
   mylog(LOG_INFO, "Starting up.\n");

From 608e5c09b77195847f7c9f44825ca7013a788ac6 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 2 Nov 2025 19:41:42 +0100
Subject: [PATCH 18/26] added settings logging for log verbosity level 1

---
 cpiped.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/cpiped.c b/cpiped.c
index fc32b8e..27905e9 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -243,6 +243,19 @@ int main(int argc, char *argv[]) {
   write(pidfd, pidstr, strlen(pidstr));
   close(pidfd);
 
+  // Log configurations
+  if (log_verb) {
+    mylogverb(LOG_INFO, 1, "Demonize: '%d'\n", daemonize);
+    mylogverb(LOG_INFO, 1, "Log verbosity level: '%d'\n", log_verb);
+    mylogverb(LOG_INFO, 1, "Pid path: '%s'\n", pidpath);
+    mylogverb(LOG_INFO, 1, "Capture device: '%s'\n", capdev);
+    mylogverb(LOG_INFO, 1, "Sample rate: '%d'\n", samplerate);
+    mylogverb(LOG_INFO, 1, "Buffer duration: '%f'\n", bufdur);
+    mylogverb(LOG_INFO, 1, "Sound detect command: '%s'\n", startcmd);
+    mylogverb(LOG_INFO, 1, "Silence detect command: '%s'\n", endcmd);
+    mylogverb(LOG_INFO, 1, "Silence threshold: '%d'\n", silentt);  
+  }
+
   // Open the FIFO for read first, so the open for write succeeds.
   readfd = open(fifonam, O_RDONLY | O_NONBLOCK);
   if (readfd <= 0) {

From c803b27c42de156abe4337937c49a64530912a03 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 2 Nov 2025 19:47:29 +0100
Subject: [PATCH 19/26] modified bufsize calculation

- made out pipe size twice the capture buffer size
- added error message when pipe resizing fails
- added warning when pipe size different from the requested one
---
 cpiped.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 27905e9..001330b 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -277,9 +277,6 @@ int main(int argc, char *argv[]) {
   }
   close(readfd);
 
-  // Set the FIFO size to 8192 bytes to minimize latency
-  fcntl(writefd, F_SETPIPE_SZ, 8192);
-
   // Open PCM device for recording (capture).
   rc = snd_pcm_open(&handle, capdev, SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK);
   if (rc != 0) {
@@ -293,8 +290,8 @@ int main(int argc, char *argv[]) {
   snd_pcm_hw_params_set_channels(handle, params, capchannels);
   snd_pcm_hw_params_set_rate_near(handle, params, &samplerate, &dir);
 
-  // set buffer size in bit
-  bufsize = bufdur * samplerate * capchannels * 8;
+  // set buffer size in byte
+  bufsize = bufdur * samplerate * capchannels * (samplesize / 8);
 
   // Set period size to 1024 frames.
   frames = 1024;
@@ -316,6 +313,16 @@ int main(int argc, char *argv[]) {
   capbuffer = calloc(capsize, sizeof(char));
   scapbuffer = (int16_t*)capbuffer;
 
+  // Set the FIFO size to twice the period size
+  int pipesize = fcntl(writefd, F_SETPIPE_SZ, 2 * capsize);
+  if (pipesize < 0) {
+    mylog(LOG_ERR, "Error setting FIFO size: %s\n", strerror(errno));
+    goto error;
+  }
+  if (pipesize != 2 * capsize) {
+    mylog(LOG_NOTICE, "WARN setting FIFO size to %ld, actual size %ld\n", 2*capsize, pipesize);
+  }
+
   // Determine write size
   writebytes = capsize - 32 ; // Write a bit less to make sure write controls pace
 

From 3db6206dc735895b811f84cef4a4622d8077cded Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 2 Nov 2025 19:50:17 +0100
Subject: [PATCH 20/26] added export as env variables for sample size, rate and
 capture channel count

- variable name for sample rate is CPIPED_SR
- variable name for sample size is CPIPED_SS
- variable name for channel count is CPIPED_CC
- those can be used by the called script to perform format conversion or other arithmetic if needed
---
 cpiped.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/cpiped.c b/cpiped.c
index 001330b..07b9bb5 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -76,6 +76,34 @@ void myterm() {
   exit(EXIT_SUCCESS);
 }
 
+int setenvvar(const char *var_name, size_t var_val_len, unsigned int var_overwrite, const char *format, ...) {
+  va_list args;
+  va_start (args, format);
+
+  char *var_value;
+  int ret;
+
+  // allocate space for the variable value
+  var_value = malloc((var_val_len + 1) * sizeof(char));
+
+  if (var_value == NULL) {
+    mylog(LOG_ERR, "Unable to allocate memory for ENV variable setup '%s'\n", strerror(errno));
+    return 1;
+  }
+
+  // set variable value as string
+  vsnprintf(var_value, var_val_len + 1, format, args);
+
+  // Set the variable
+  ret = setenv(var_name, var_value, var_overwrite);
+
+  // Clean-up
+  free(var_value);
+  va_end(args);
+
+  return ret;
+}
+
 int main(int argc, char *argv[]) {
   int rc;
   int capsize;
@@ -332,6 +360,14 @@ int main(int argc, char *argv[]) {
   bufstart = 0;
   bufend = 0;
 
+  // Export capture parameters to ENV variables
+  if (setenvvar("CPIPED_SR", 6, 1, "%ld", samplerate) == -1)
+    mylog(LOG_NOTICE, "WARN CPIPED_SR to '%ld' FAILED\n", samplerate);
+  if (setenvvar("CPIPED_SS", 2, 1, "%ld", samplesize) == -1)
+    mylog(LOG_NOTICE, "WARN CPIPED_SS to '%ld' FAILED\n", samplesize);
+  if (setenvvar("CPIPED_CC", 2, 1, "%d", capchannels) == -1)
+    mylog(LOG_NOTICE, "WARN CPIPED_CC to '%d' FAILED\n", capchannels);
+
   while (1) {
     // Capture samples
     if (!wrote) // When not writing, wait a bit between captures.

From ee3b52c327f7628ab91d7b9bf84185d054ca8985 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 2 Nov 2025 19:51:17 +0100
Subject: [PATCH 21/26] added comments in the signal processing section

---
 cpiped.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/cpiped.c b/cpiped.c
index 07b9bb5..ba42e41 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -372,7 +372,7 @@ int main(int argc, char *argv[]) {
     // Capture samples
     if (!wrote) // When not writing, wait a bit between captures.
       usleep(capusec * .95);
-    rc = snd_pcm_readi(handle, capbuffer, frames);
+    rc = snd_pcm_readi(handle, capbuffer, frames); // return number of captured frames
     if (rc == -EPIPE) { // EPIPE means overrun
       mylog(LOG_NOTICE, "Overrun occurred\n");
       snd_pcm_prepare(handle);
@@ -385,6 +385,7 @@ int main(int argc, char *argv[]) {
     // Check if there is sound and if so compute RMS power level regularly and count sounds and silences
     if (capcount > 10 && rc > 0) { // Approx. every quarter second
       power = 0;
+      // Each frame holds one sample per channel
       for (i = 0; i < rc / 2; i++) {
         power += pow(scapbuffer[i], 2) + pow(scapbuffer[i + 1], 2);
       }
@@ -450,7 +451,7 @@ int main(int argc, char *argv[]) {
       if ((buffull == 1) && (bufused < (int)bufsize / 2))
         buffull = 0;
 
-      if (!buffull  && rc > 0) {
+      if (!buffull && rc > 0) {
         // Store samples in buffer
         readbytes = rc * (samplesize / 8) * capchannels;
         bufendtoend = bufsize - bufend;

From 8594b2d147d104adfb24ea2e140bfb4692ff36c0 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 14 Dec 2025 16:40:57 +0100
Subject: [PATCH 22/26] fixed default sample rate

---
 cpiped.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cpiped.c b/cpiped.c
index ba42e41..d9034b4 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -108,7 +108,7 @@ int main(int argc, char *argv[]) {
   int rc;
   int capsize;
   snd_pcm_hw_params_t *params;
-  unsigned int samplerate = 41000;
+  unsigned int samplerate = 44100;
   unsigned int samplesize = 16;
   unsigned int capchannels = 2;
   unsigned int capusec;

From cb31ba11887ea1cce07ac98bb3b45f6e5834666d Mon Sep 17 00:00:00 2001
From: Alessandro Gritti <ale275@gmail.com>
Date: Sun, 28 Dec 2025 19:08:34 +0100
Subject: [PATCH 23/26] Create build workflow

---
 .github/workflows/cpiped-build.yml | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 .github/workflows/cpiped-build.yml

diff --git a/.github/workflows/cpiped-build.yml b/.github/workflows/cpiped-build.yml
new file mode 100644
index 0000000..c121090
--- /dev/null
+++ b/.github/workflows/cpiped-build.yml
@@ -0,0 +1,21 @@
+name: cpiped build
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: install alsasound
+      run: sudo apt install -y libasound2-dev
+    - uses: actions/checkout@v4
+    - name: make
+      run: make
+    - name: check executable
+      run: bash -c "[[ -x cpiped ]]"

From 373c001550dc752fe5ab2affe9534924c94d5e7d Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Sun, 28 Dec 2025 20:53:01 +0100
Subject: [PATCH 24/26] README overhaul

---
 README.md | 131 +++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 120 insertions(+), 11 deletions(-)

diff --git a/README.md b/README.md
index 9a0f1fd..62c1b28 100644
--- a/README.md
+++ b/README.md
@@ -1,15 +1,124 @@
-cpiped (https://github.com/b-fitzpatrick/cpiped) captures an audio stream and outputs it to a pipe with a bit of buffering
-to handle clock mismatch. It also includes silence/sound detection and the ability
-to run a command on detection.
+<h1>cpiped</h1>
 
-I'm using this to capture line-in audio from a sound card and send it to 
-forked-daapd (https://github.com/ejurgensen/forked-daapd). On sound detection, it
-runs a simple script to start playing the associated pipe in forked-daapd.
+[![Release][release-shield]][release-url]
+![GitHub commit activity][commit-shield]
+[![Issues][issues-shield]][issues-url]
+[![Contributors][contributors-shield]][contributors-url]
+[![project_license][license-shield]][license-url]
+[![Stargazers][stars-shield]][stars-url]
+[![Forks][forks-shield]][forks-url]
+![Build flow][build-shield]
 
-#### Merged work
-- NDpiped builds on cpiped but modifies code such that the buffer is only written if there is sound.  Otherwise I found buffer was constantly writing and Forked-Daapd was playing silence rather then my playlist. (https://github.com/natedreger/cpiped) and (https://github.com/natedreger/NDpiped)
-- Parametrized pid file by Mario Wenzel (https://github.com/maweki/cpiped)
+    cpiped captures an audio stream and outputs it to a pipe
 
-#### ToDo(s)
+`cpiped` was born  to capture line-in audio from a sound card and send it to [forked-daapd](https://github.com/ejurgensen/forked-daapd). On sound detection, it runs a simple script to start playing the associated pipe in forked-daapd.
+
+## Contents
+- [Contents](#contents)
+- [Features](#features)
+- [Getting Started](#getting-started)
+  - [Prerequisites](#prerequisites)
+  - [Installation](#installation)
+- [Usage](#usage)
+  - [Options](#options)
+  - [Env variables](#env-variables)
+- [ToDo(s)](#todos)
+- [Acknowledgments](#acknowledgments)
+  - [Top contributors:](#top-contributors)
+
+## Features
+- Buffering to handle clock mismatch
+- Command execution on sound and silence detection
+- User defined noise threshold  
+- Different sample rate handling
+- Multiple instances running in parallel thanks to parametrized pid
+
+## Getting Started
+
+### Prerequisites
+`cpiped` relies on [ALSA lib]( http://www.alsa-project.org) as only prerequisite
+
+- Debian
+  ```sh
+  sudo apt install -y libasound2-dev
+  ```
+
+### Installation
+1. Clone the repository
+   ```sh
+   git clone https://github.com/ale275/cpiped.git
+   ```
+2. Make cpiped
+   ```sh
+   cd cpiped
+   make
+   ```
+4. Install cpiped
+   ```sh
+   sudo install cpiped /usr/local/sbin/
+   ```
+
+## Usage
+
+`cpiped` is an application meant to be run from command line or demonized
+
+```sh
+cpiped [-s arg] [-e arg] [OPTIONS] FIFO
+```
+FIFO: path to the named pipe where sound will be written
+
+### Options
+
+| Option | Description                                                   | Type      | Default                 | Range            | Required? |
+| ------ | ------------------------------------------------------------- | --------- | ----------------------- | ---------------- | --------- |
+| `-d`   | ALSA capture device in *hw:\<card>,\<device>* format.         | `string`  | `'default'`             |                  | Yes       |
+| `-f`   | ALSA capture device sample rate in Hz.                        | `integer` | `44100`                 | `16000 - 192000` | No        |
+| `-b`   | Buffer size in seconds.                                       | `float`   | `.25`                   | `.1 - 5.0`       | No        |
+| `-s`   | Command to run, in background, when sound is detected.        | `string`  |                         |                  | Yes       |
+| `-e`   | Command to run, in background, when silence is detected.      | `string`  |                         |                  | Yes       |
+| `-t`   | Silence threshold expressed as signal power.                  | `integer` | `100`                   | `1 - 32767`      | No        |
+| `-D`   | Daemonize.                                                    | `bool`    |                         |                  | No        |
+| `-p`   | Path to pidfile.                                              | `string`  | `'/var/run/cpiped.pid'` |                  | No        |
+| `-v`   | Log verbosity. (`-vv` and `-vvv` for higher verbosity levels) | `bool`    |                         |                  | No        |
+
+### Env variables
+On start `cpiped` will set the following env variables
+- *CPIPED_SR* audio capture sample rate
+- *CPIPED_SS* audio capture sample size
+- *CPIPED_CC* audio capture channel(s) count
+
+Those variables are visible by the sound and silence detect commands
+
+## ToDo(s)
 - [ ] Improve Makefile to create dedicated build folder
-- [ ] Improve Makefile to add install directive
\ No newline at end of file
+- [ ] Improve Makefile to add install directive
+
+See the [open issues](https://github.com/ale275/cpiped/issues) for a full list of proposed features (and known issues).
+
+## Acknowledgments
+
+* [cpiped](https://github.com/b-fitzpatrick/cpiped) original code of cpiped by [b-fitzpatrick](https://github.com/b-fitzpatrick)
+* [NDpiped](https://github.com/natedreger/NDpiped) modified version writing the buffer only when sound was detected
+* [maweki cpiped fork](https://github.com/maweki/cpiped) for parametrized pid file
+
+### Top contributors:
+
+<a href="https://github.com/ale275/cpiped/graphs/contributors">
+  <img src="https://contrib.rocks/image?repo=ale275/cpiped" alt="contrib.rocks image" />
+</a>
+
+<!-- variables -->
+[build-shield]: https://github.com/ale275/cpiped/actions/workflows/cpiped-build.yml/badge.svg
+[commit-shield]: https://img.shields.io/github/commit-activity/t/ale275/cpiped?style=flat
+[release-shield]: https://img.shields.io/github/release/ale275/cpiped.svg?colorB=58839b
+[release-url]: https://github.com/ale275/cpiped/releases/latest
+[contributors-shield]: https://img.shields.io/github/contributors/ale275/cpiped.svg
+[contributors-url]: https://github.com/ale275/cpiped/graphs/contributors
+[forks-shield]: https://img.shields.io/github/forks/ale275/cpiped.svg?style=flat
+[forks-url]: https://github.com/github_usale275ername/cpiped/network/members
+[stars-shield]: https://img.shields.io/github/stars/ale275/cpiped.svg?style=flat
+[stars-url]: https://github.com/ale275/cpiped/stargazers
+[issues-shield]: https://img.shields.io/github/issues/ale275/cpiped.svg
+[issues-url]: https://github.com/ale275/cpiped/issues
+[license-shield]: https://img.shields.io/github/license/ale275/cpiped.svg
+[license-url]: https://github.com/ale275/cpiped/blob/master/LICENSE
\ No newline at end of file

From 9d85652e1290dc7a30fc73b1a89835555d96fe59 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Mon, 26 Jan 2026 20:46:17 +0100
Subject: [PATCH 25/26] added check to revert to default sample rate if no
 value is specified as -f argument

---
 cpiped.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/cpiped.c b/cpiped.c
index d9034b4..a4d44f7 100644
--- a/cpiped.c
+++ b/cpiped.c
@@ -197,7 +197,10 @@ int main(int argc, char *argv[]) {
       break;
     case 'f':
       samplerate = atoi(optarg);
-      if ((samplerate < 16000) || (samplerate > 192000)) {
+      if (samplerate == 0) {
+        mylog(LOG_INFO, "No sample rate specified. Reverting to default.\n");
+        samplerate = 44100;
+      } else if ((samplerate < 16000) || (samplerate > 192000)) {
         mylog(LOG_ERR, "Invalid sample rate. Range is 16000-192000.\n");
         goto error;
       }

From c349cdceb55bc75921d4fcff3eac09bd45763ce1 Mon Sep 17 00:00:00 2001
From: ale275 <ale275@gmail.com>
Date: Mon, 26 Jan 2026 21:18:33 +0100
Subject: [PATCH 26/26] README updated to add "made with C" shield

---
 README.md | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index 62c1b28..202e382 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,8 @@
 [![Forks][forks-shield]][forks-url]
 ![Build flow][build-shield]
 
+![c][c-shield]
+
     cpiped captures an audio stream and outputs it to a pipe
 
 `cpiped` was born  to capture line-in audio from a sound card and send it to [forked-daapd](https://github.com/ejurgensen/forked-daapd). On sound detection, it runs a simple script to start playing the associated pipe in forked-daapd.
@@ -36,7 +38,7 @@
 ## Getting Started
 
 ### Prerequisites
-`cpiped` relies on [ALSA lib]( http://www.alsa-project.org) as only prerequisite
+`cpiped` relies on [ALSA lib](http://www.alsa-project.org) as only prerequisite
 
 - Debian
   ```sh
@@ -71,7 +73,7 @@ FIFO: path to the named pipe where sound will be written
 
 | Option | Description                                                   | Type      | Default                 | Range            | Required? |
 | ------ | ------------------------------------------------------------- | --------- | ----------------------- | ---------------- | --------- |
-| `-d`   | ALSA capture device in *hw:\<card>,\<device>* format.         | `string`  | `'default'`             |                  | Yes       |
+| `-d`   | ALSA capture device in *hw:\<card>,\<device>* format.         | `string`  | `'default'`             |                  | No        |
 | `-f`   | ALSA capture device sample rate in Hz.                        | `integer` | `44100`                 | `16000 - 192000` | No        |
 | `-b`   | Buffer size in seconds.                                       | `float`   | `.25`                   | `.1 - 5.0`       | No        |
 | `-s`   | Command to run, in background, when sound is detected.        | `string`  |                         |                  | Yes       |
@@ -83,8 +85,8 @@ FIFO: path to the named pipe where sound will be written
 
 ### Env variables
 On start `cpiped` will set the following env variables
-- *CPIPED_SR* audio capture sample rate
-- *CPIPED_SS* audio capture sample size
+- *CPIPED_SR* audio capture sample rate in *Hz*
+- *CPIPED_SS* audio capture sample size in *bit(s)*
 - *CPIPED_CC* audio capture channel(s) count
 
 Those variables are visible by the sound and silence detect commands
@@ -115,10 +117,11 @@ See the [open issues](https://github.com/ale275/cpiped/issues) for a full list o
 [contributors-shield]: https://img.shields.io/github/contributors/ale275/cpiped.svg
 [contributors-url]: https://github.com/ale275/cpiped/graphs/contributors
 [forks-shield]: https://img.shields.io/github/forks/ale275/cpiped.svg?style=flat
-[forks-url]: https://github.com/github_usale275ername/cpiped/network/members
+[forks-url]: https://github.com/ale275/cpiped/network/members
 [stars-shield]: https://img.shields.io/github/stars/ale275/cpiped.svg?style=flat
 [stars-url]: https://github.com/ale275/cpiped/stargazers
 [issues-shield]: https://img.shields.io/github/issues/ale275/cpiped.svg
 [issues-url]: https://github.com/ale275/cpiped/issues
 [license-shield]: https://img.shields.io/github/license/ale275/cpiped.svg
-[license-url]: https://github.com/ale275/cpiped/blob/master/LICENSE
\ No newline at end of file
+[license-url]: https://github.com/ale275/cpiped/blob/master/LICENSE
+[c-shield]: https://img.shields.io/badge/made%20with%20C-1f425f?style=flat&logo=c&logoColor=white
\ No newline at end of file