X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/disorder/blobdiff_plain/e03eb69edbcd171f32edf369af2c766c383e4c16..6cad0c845dc5d6f6b4d4cc5e9ae7aee39d279b49:/lib/uaudio-command.c

diff --git a/lib/uaudio-command.c b/lib/uaudio-command.c
index 6b7ef66..57e8762 100644
--- a/lib/uaudio-command.c
+++ b/lib/uaudio-command.c
@@ -17,7 +17,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 /** @file lib/uaudio-command.c
- * @brief Support for commmand backend */
+ * @brief Support for commmand backend
+ *
+ * We use the code in @ref lib/uaudio-schedule.c to ensure that we write at
+ * approximately the 'real' rate.  For disorder-playrtp this isn't very useful
+ * (thought it might reduce the size of various buffers downstream of us) but
+ * when run from the speaker it means that pausing stands a chance of working.
+ */
 #include "common.h"
 
 #include <errno.h>
@@ -28,6 +34,7 @@
 #include "mem.h"
 #include "wstat.h"
 #include "uaudio.h"
+#include "configuration.h"
 
 /** @brief Pipe to subprocess */
 static int command_fd;
@@ -35,8 +42,12 @@ static int command_fd;
 /** @brief Child process ID */
 static pid_t command_pid;
 
+/** @brief Whether to suspend on pause */
+static int command_suspend_on_pause;
+
 static const char *const command_options[] = {
   "command",
+  "pause-mode",
   NULL
 };
 
@@ -63,7 +74,7 @@ static void command_open(void) {
   int pfd[2];
   const char *command;
 
-  if(!(command = uaudio_get("command")))
+  if(!(command = uaudio_get("command", NULL)))
     fatal(0, "'command' not set");
   xpipe(pfd);
   command_pid = xfork();
@@ -84,7 +95,12 @@ static void command_open(void) {
 }
 
 /** @brief Send audio data to subprocess */
-static size_t command_play(void *buffer, size_t nsamples) {
+static size_t command_play(void *buffer, size_t nsamples, unsigned flags) {
+  uaudio_schedule_sync();
+  /* If we're pausing and want that to be represented by stopping writing, we
+   * just pretend */
+  if((flags & UAUDIO_PAUSED) && command_suspend_on_pause)
+    return nsamples;
   const size_t bytes = nsamples * uaudio_sample_size;
   int written = write(command_fd, buffer, bytes);
   if(written < 0) {
@@ -100,17 +116,33 @@ static size_t command_play(void *buffer, size_t nsamples) {
       fatal(errno, "error writing to audio command subprocess");
     }
   }
-  return written / uaudio_sample_size;
+  /* TODO what if we write a partial sample? Actually reasonably unlikely but
+   * not impossible.  Maybe someone who actually uses this backend should sort
+   * it out. */
+  const size_t written_samples = written / uaudio_sample_size;
+  uaudio_schedule_sent(written_samples);
+  return written_samples;
 }
 
 static void command_start(uaudio_callback *callback,
                       void *userdata) {
+  const char *pausemode = uaudio_get("pause-mode", "silence");
+  unsigned flags = 0;
+
+  if(!strcmp(pausemode, "silence"))
+    command_suspend_on_pause = 0;
+  else if(!strcmp(pausemode, "suspend"))
+    command_suspend_on_pause = 1;
+  else
+    fatal(0, "unknown pause mode '%s'", pausemode);
   command_open();
+  uaudio_schedule_init();
   uaudio_thread_start(callback,
                       userdata,
                       command_play,
                       uaudio_channels,
-		      4096 / uaudio_sample_size);
+		      4096 / uaudio_sample_size,
+                      flags);
 }
 
 static void command_stop(void) {
@@ -118,12 +150,9 @@ static void command_stop(void) {
   command_wait();
 }
 
-static void command_activate(void) {
-  uaudio_thread_activate();
-}
-
-static void command_deactivate(void) {
-  uaudio_thread_deactivate();
+static void command_configure(void) {
+  uaudio_set("command", config->speaker_command);
+  uaudio_set("pause-mode", config->pause_mode);
 }
 
 const struct uaudio uaudio_command = {
@@ -131,8 +160,9 @@ const struct uaudio uaudio_command = {
   .options = command_options,
   .start = command_start,
   .stop = command_stop,
-  .activate = command_activate,
-  .deactivate = command_deactivate
+  .activate = uaudio_thread_activate,
+  .deactivate = uaudio_thread_deactivate,
+  .configure = command_configure,
 };
 
 /*