-/*
+/* alsa/ardour dbus device request tool
+ *
* Copyright (C) 2014 Robin Gareus <robin@gareus.org>
*
* This program is free software; you can redistribute it and/or modify
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
+// NB generate man-page with
+// help2man -N -n "alsa/ardour dbus device request tool" -o ardour-request-device.1 ./build/libs/ardouralsautil/ardour-request-device
+
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
+#include <getopt.h>
#include <signal.h>
#include <string.h>
#include <fcntl.h>
#include "ardouralsautil/reserve.h"
+#ifndef ARD_PROG_NAME
+#define ARD_PROG_NAME "alsa_request_device"
+#endif
+#ifndef ARD_APPL_NAME
+#define ARD_APPL_NAME "ALSA User"
+#endif
+#ifndef VERSION
+#define VERSION "v0.3"
+#endif
+
static int run = 1;
+static int release_wait_for_signal = 0;
+static pid_t parent_pid = 0;
static void wearedone(int sig) {
(void) sig; // skip 'unused variable' compiler warning;
return errno != EBADF;
}
+static void print_version(int status) {
+ printf (ARD_PROG_NAME " " VERSION "\n\n");
+ printf (
+ "Copyright (C) 2014 Robin Gareus <robin@gareus.org>\n"
+ "This is free software; see the source for copying conditions. There is NO\n"
+ "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\n"
+ );
+ exit (status);
+}
+
static void usage(int status) {
- printf ("ardour-request-device - DBus Audio Reservation Utility.\n");
- printf ("Usage:
ardour-request-device [ OPTIONS ] <Audio-Device-ID>\n");
+ printf (ARD_PROG_NAME " - DBus Audio Reservation Utility.\n");
+ printf ("Usage:
" ARD_PROG_NAME " [ OPTIONS ] <Audio-Device-ID>\n");
printf ("Options:\n\
-h, --help display this help and exit\n\
+ -p, --priority <int> reservation priority (default: int32_max)\n\
+ -P, --pid <int> process-id to watch (default 0: none)\n\
+ -n, --name <string> application name to use for registration\n\
-V, --version print version information and exit\n\
+ -w, --releasewait wait for signal on yield-release\n\
");
printf ("\n\
This tool issues a dbus request to reserve an ALSA Audio-device.\n\
If successful other users of the device (e.g. pulseaudio) will\n\
-release the device so that ardour can access it.\n\
+release the device.\n\
\n\
-ardour-request-device announces itself as \"Ardour ALSA Backend\" and uses the\n\
-maximum possible priority for requesting the device.\n\
+" ARD_PROG_NAME " by default announces itself as \"" ARD_APPL_NAME "\"\n\
+and uses the maximum possible priority for requesting the device.\n\
+These settings can be overridden using the -n and -p options respectively.\n\
+\n\
+If a PID is given the tool will watch the process and if that is not running\n\
+release the device and exit. Otherwise " ARD_PROG_NAME " runs until\n\
+either stdin is closed, a SIGINT or SIGTERM is received or some other\n\
+application requests the device with a higher priority.\n\
+\n\
+Without the -w option, " ARD_PROG_NAME " yields the device after 500ms to\n\
+any higher-priority request. With the -w option this tool waits until it\n\
+for SIGINT or SIGTERM - but at most 4 sec to acknowledge before releasing.\n\
\n\
The audio-device-id is a string e.g. 'Audio1'\n\
\n\
Examples:\n\
-ardour-request-device Audio0\n\
+" ARD_PROG_NAME " Audio0\n\
\n");
printf ("Report bugs to Robin Gareus <robin@gareus.org>\n");
exit (status);
}
-static void print_version(void) {
- printf ("ardour-request-device 0.1\n\n");
- printf (
- "Copyright (C) 2014 Robin Gareus <robin@gareus.org>\n"
- "This is free software; see the source for copying conditions. There is NO\n"
- "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\n"
- );
- exit (0);
+static struct option const long_options[] =
+{
+ {"help", no_argument, 0, 'h'},
+ {"name", required_argument, 0, 'n'},
+ {"pid", required_argument, 0, 'P'},
+ {"priority", required_argument, 0, 'p'},
+ {"version", no_argument, 0, 'V'},
+ {"releasewait", no_argument, 0, 'w'},
+ {NULL, 0, NULL, 0}
+};
+
+static int request_cb(rd_device *d, int forced) {
+ (void) d; // skip 'unused variable' compiler warning;
+ (void) forced; // skip 'unused variable' compiler warning;
+ fprintf(stdout, "Received higher priority request - releasing device.\n");
+ fflush(stdout);
+ if(!release_wait_for_signal) {
+ usleep (500000);
+ run = 0;
+ } else if (run) {
+ int timeout = 4000;
+ fprintf(stdout, "Waiting for acknowledge signal to release.\n");
+ while (release_wait_for_signal && run && --timeout) {
+ if (!stdin_available()) {
+ break;
+ }
+ if (parent_pid > 0 && kill (parent_pid, 0)) {
+ break;
+ }
+ usleep (1000);
+ }
+ run = 0;
+ }
+ return 1; // OK
}
int main(int argc, char **argv) {
DBusConnection* dbus_connection = NULL;
rd_device * reserved_device = NULL;
DBusError error;
- int ret;
+ int ret, c;
- if (argc < 2 || argc > 2) {
- usage(EXIT_FAILURE);
- }
- if (!strcmp(argv[1], "-V") || !strcmp(argv[1], "--version")) {
- print_version();
+ int32_t priority = INT32_MAX;
+ char *name = strdup(ARD_APPL_NAME);
+
+ while ((c = getopt_long (argc, argv,
+ "h" /* help */
+ "n:" /* name */
+ "P:" /* pid */
+ "p:" /* priority */
+ "V" /* version */
+ "w", /* release wait for signal */
+ long_options, (int *) 0)) != EOF)
+ {
+ switch (c) {
+ case 'h':
+ free(name);
+ usage(EXIT_SUCCESS);
+ break;
+ case 'n':
+ free(name);
+ name = strdup(optarg);
+ break;
+ case 'p':
+ priority = atoi (optarg);
+ if (priority < 0) priority = 0;
+ break;
+ case 'P':
+ parent_pid = atoi (optarg);
+ break;
+ case 'V':
+ free(name);
+ print_version(EXIT_SUCCESS);
+ break;
+ case 'w':
+ release_wait_for_signal = 1;
+ break;
+ default:
+ free(name);
+ usage(EXIT_FAILURE);
+ break;
+ }
}
- if (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help")) {
- usage(EXIT_SUCCESS);
+
+ if (optind + 1 != argc) {
+ free(name);
+ usage(EXIT_FAILURE);
}
+ const char *device_name = argv[optind];
- const char *device_name = argv[1];
+ if (parent_pid > 0 && kill (parent_pid, 0)) {
+ fprintf(stderr, "Given PID to watch is not running.\n");
+ free(name);
+ return EXIT_FAILURE;
+ }
dbus_error_init(&error);
if (!(dbus_connection = dbus_bus_get (DBUS_BUS_SESSION, &error))) {
fprintf(stderr, "Failed to connect to session bus for device reservation: %s\n", error.message ? error.message : "unknown error.");
dbus_error_free(&error);
+ free(name);
return EXIT_FAILURE;
}
&reserved_device,
dbus_connection,
device_name,
- "Ardour ALSA Backend",
- INT32_MAX,
- NULL,
+ name,
+ priority,
+ request_cb,
&error)) < 0)
{
fprintf(stderr, "Failed to acquire device: '%s'\n%s\n", device_name, (error.message ? error.message : strerror(-ret)));
dbus_error_free(&error);
dbus_connection_unref(dbus_connection);
+ free(name);
return EXIT_FAILURE;
}
while (run && dbus_connection_read_write_dispatch (dbus_connection, 200)) {
if (!stdin_available()) {
- fprintf(stderr, "stdin closed - shutting down.\n");
+ fprintf(stderr, "stdin closed - releasing device.\n");
+ break;
+ }
+ if (parent_pid > 0 && kill (parent_pid, 0)) {
+ fprintf(stderr, "watched PID no longer exists - releasing device.\n");
break;
}
}
rd_release (reserved_device);
fprintf(stdout, "Released audio-card '%s'\n", device_name);
- dbus_error_free(&error);
+
dbus_connection_unref(dbus_connection);
+ dbus_error_free(&error);
+ free(name);
return EXIT_SUCCESS;
}
projects / ardour.git / blobdiff