From 287ad384814351a195696f91e83388c12b265f90 Mon Sep 17 00:00:00 2001
Message-Id: <287ad384814351a195696f91e83388c12b265f90.1714831099.git.mdw@distorted.org.uk>
From: Mark Wooding <mdw@chiark.greenend.org.uk>
Date: Sat, 14 Mar 2009 09:28:20 +0000
Subject: [PATCH] The command backend now supports the old (suspending) and new
 (silence) pause behaviors via an option.  disorder-playrtp gains --pause-mode
 t o set this option.
Organization: Straylight/Edgeware

From: Richard Kettlewell <rjk@greenend.org.uk>

---
 clients/playrtp.c         |  8 ++++++--
 doc/disorder-playrtp.1.in |  9 ++++++++-
 lib/uaudio-command.c      | 12 +++++++++++-
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/clients/playrtp.c b/clients/playrtp.c
index d97864b..338cbbf 100644
--- a/clients/playrtp.c
+++ b/clients/playrtp.c
@@ -217,6 +217,7 @@ static const struct option options[] = {
 #endif
   { "dump", required_argument, 0, 'r' },
   { "command", required_argument, 0, 'e' },
+  { "pause-mode", required_argument, 0, 'P' },
   { "socket", required_argument, 0, 's' },
   { "config", required_argument, 0, 'C' },
   { 0, 0, 0, 0 }
@@ -492,7 +493,9 @@ static void help(void) {
 #if HAVE_COREAUDIO_AUDIOHARDWARE_H
           "  --core-audio, -c        Use Core Audio to play audio\n"
 #endif
-          "  --command, -e COMMAND   Pipe audio to command\n"
+          "  --command, -e COMMAND   Pipe audio to command.\n"
+          "  --pause-mode, -P silence  For -e: pauses send silence (default)\n"
+          "  --pause-mode, -P suspend  For -e: pauses suspend writes\n"
 	  "  --help, -h              Display usage message\n"
 	  "  --version, -V           Display version number\n"
           );
@@ -592,7 +595,7 @@ int main(int argc, char **argv) {
   mem_init();
   if(!setlocale(LC_CTYPE, "")) fatal(errno, "error calling setlocale");
   backend = uaudio_apis[0];
-  while((n = getopt_long(argc, argv, "hVdD:m:b:x:L:R:M:aocC:re:", options, 0)) >= 0) {
+  while((n = getopt_long(argc, argv, "hVdD:m:b:x:L:R:M:aocC:re:P:", options, 0)) >= 0) {
     switch(n) {
     case 'h': help();
     case 'V': version("disorder-playrtp");
@@ -616,6 +619,7 @@ int main(int argc, char **argv) {
     case 's': control_socket = optarg; break;
     case 'r': dumpfile = optarg; break;
     case 'e': backend = &uaudio_command; uaudio_set("command", optarg); break;
+    case 'P': uaudio_set("pause-mode", optarg); break;
     default: fatal(0, "invalid option");
     }
   }
diff --git a/doc/disorder-playrtp.1.in b/doc/disorder-playrtp.1.in
index ea4c93f..206be91 100644
--- a/doc/disorder-playrtp.1.in
+++ b/doc/disorder-playrtp.1.in
@@ -66,7 +66,8 @@ If \fICOMMAND\fR exits it is re-executed; any samples that had been written to
 the pipe but not processed by the previous instance will be lost.
 .IP
 .B \-\-device
-is redundant with this option.
+is redundant with this option, but you might wan to set
+.BR \-\-pause\-mode .
 .IP
 As an example,
 .B "-e \(aqcat > dump\(aq"
@@ -75,6 +76,12 @@ You could convert it to another format with, for instance:
 .IP
 .B "sox -c2 -traw -r44100 -s -w dump dump.wav"
 .TP
+.B \-\-pause\-mode \fIMODE\fR, \fB-P \fIMODE
+Set the pause mode for \fB\-\-command\fR to either \fBsilence\fR (the default), in
+which pauses are represented by sending silent samples, or \fBsuspend\fR, in which
+writes to  the subprocess are suspended, requiring it to infer a pause from flow
+control.
+.TP
 .B \-\-config \fIPATH\fR, \fB\-C \fIPATH
 Set the configuration file.
 The default is
diff --git a/lib/uaudio-command.c b/lib/uaudio-command.c
index 096888d..812a3f2 100644
--- a/lib/uaudio-command.c
+++ b/lib/uaudio-command.c
@@ -44,6 +44,7 @@ static pid_t command_pid;
 
 static const char *const command_options[] = {
   "command",
+  "pause-mode",
   NULL
 };
 
@@ -115,6 +116,15 @@ static size_t command_play(void *buffer, size_t nsamples) {
 
 static void command_start(uaudio_callback *callback,
                       void *userdata) {
+  const char *pausemode = uaudio_get("pause-mode", "silence");
+  unsigned flags = 0;
+
+  if(!strcmp(pausemode, "silence"))
+    flags |= UAUDIO_THREAD_FAKE_PAUSE;
+  else if(!strcmp(pausemode, "suspend"))
+    ;
+  else
+    fatal(0, "unknown pause mode '%s'", pausemode);
   command_open();
   uaudio_schedule_init();
   uaudio_thread_start(callback,
@@ -122,7 +132,7 @@ static void command_start(uaudio_callback *callback,
                       command_play,
                       uaudio_channels,
 		      4096 / uaudio_sample_size,
-                      UAUDIO_THREAD_FAKE_PAUSE);
+                      flags);
 }
 
 static void command_stop(void) {
-- 
[mdw]