will loop audio on pi at boot until power off

2020-02-25 17:16:16 +10:30 · 2020-02-25 17:16:16 +10:30 · 5edb9a08e6
parent a78dd9e4b2
commit 5edb9a08e6
1 changed files with 150 additions and 0 deletions
--- a/cmd/audio-player/looper/main.go
+++ b/cmd/audio-player/looper/main.go
@ -0,0 +1,150 @@
+/*
+NAME
+  test-audio/main.go
+
+AUTHORS
+  Ella Pietraroia <ella@ausocean.org>
+
+LICENSE
+  revid is Copyright (C) 2017-2020 the Australian Ocean Lab (AusOcean)
+
+  It is free software: you can redistribute it and/or modify them
+  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.
+
+  It 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
+  in gpl.txt.  If not, see http://www.gnu.org/licenses.
+*/
+
+//testing for underwater speaker audio playing on pi
+
+/*
+Pi Setup:
+pull master
+  $sudo nano main.go
+chage file variable at top of function to be wav file that you have put onto the pi (hint: spc command)
+navigate to /go/src/bitbucket.org/ausocean/av/cmd/audio-player/looper
+and build
+edit rc.local to run looper at boot
+  $sudo nano /etc/rc.local
+paste this in after comments but before 'exit 0':
+
+exec 2> /tmp/rc.local.log      # send stderr from rc.local to a log file
+exec 1>&2                      # send stdout to the same log file
+printf "rc.local started"      # show start of execution
+set -x                         # tell sh to display commands before execution
+
+AUDIOPATH=/home/pi/go/src/bitbucket.org/ausocean/av/cmd/audio-player/looper
+cd $AUDIOPATH
+
+./looper &
+
+  $systemctl enable rc-local
+  $sudo systemctl start rc-local.service
+*/
+
+package main
+
+import (
+	"bytes"
+	"io"
+	"log"
+	"os"
+	"os/exec"
+	"sync"
+	"time"
+)
+
+func main() {
+	file := "48khz.wav" //"5mStartToEndOfTrials.wav"
+
+	//making log file
+	_, err := os.Stat("audio.log")
+	if !os.IsNotExist(err) {
+		err := os.Remove("audio.log")
+		if err != nil {
+			log.Fatalf("fatal: error clearing file: %v", err)
+		}
+	}
+
+	f, err := os.OpenFile("audio.log", os.O_RDWR|os.O_CREATE, 0666) //chage to empty each time
+	if err != nil {
+		log.Fatalf("fatal: error opening file: %v", err)
+	}
+	defer f.Close()
+	log.SetOutput(f)
+
+	path, err := exec.LookPath("alsactl")
+	if err != nil {
+		log.Fatalf("fatal: didn't find 'alsactl' executable\n")
+	} else {
+		log.Printf("'alsactl' executable is in '%s'\n", path)
+	}
+
+	for {
+		cmdInit := exec.Command("alsactl", "-f", "/usr/share/doc/audioInjector/asound.state.RCA.thru.test", "restore")
+		err := cmdInit.Run()
+		if err == nil {
+			break
+		}
+		log.Printf("fatal(ish): cmd.Run() for alsactl failed with '%s'\n", err)
+		time.Sleep(1 * time.Second)
+	}
+
+	//making sure that play is on pi
+	path, err = exec.LookPath("play")
+	if err != nil {
+		log.Fatalf("fatal: didn't find 'play' executable\n")
+	} else {
+		log.Printf("'play' executable is in '%s'\n", path)
+	}
+
+	numPlays := 0
+	for {
+		numPlays++
+		log.Printf(" Number of times played: %d\n", numPlays)
+
+		cmd := exec.Command("play", file)
+
+		var stdoutBuf, stderrBuf bytes.Buffer
+		stdoutIn, _ := cmd.StdoutPipe()
+		stderrIn, _ := cmd.StderrPipe()
+
+		var errStdout, errStderr error
+		stdout := io.MultiWriter(os.Stdout, &stdoutBuf)
+		stderr := io.MultiWriter(os.Stderr, &stderrBuf)
+
+		err := cmd.Start()
+		if err != nil {
+			log.Fatalf("fatal: cmd.Start() failed with '%s'\n", err)
+		}
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+
+		go func() {
+			_, errStdout = io.Copy(stdout, stdoutIn)
+			wg.Done()
+		}()
+
+		_, errStderr = io.Copy(stderr, stderrIn)
+		wg.Wait()
+
+		err = cmd.Wait()
+		if err != nil {
+			log.Fatalf("fatal: cmd.Run() failed with %s\n", err)
+		}
+		if errStdout != nil || errStderr != nil {
+			log.Fatal("fatal: failed to capture stdout or stderr\n")
+		}
+		outStr, errStr := string(stdoutBuf.Bytes()), string(stderrBuf.Bytes())
+		log.Printf("\nout:\n%s\nerr:\n%s\n____________________________________________________\n\n", outStr, errStr)
+	}
+
+}