Merge remote-tracking branch 'origin/pr/205'

* origin/pr/205: (24 commits)
  Fix audio quality problems
  Pass streams to stream callbacks
  Avoid crashing during shutdown
  Do not rely on pw_context_get_support() on modern PipeWire
  Drop support for PipeWire < 0.3.30
  Fix package descriptions
  Set node.rate for streams
  Add utility program to run any PipeWire stream
  Use libvchan_send and libvchan_recv for all-or-nothing ops
  Allow capturing vchan size in one go
  Better error reporting
  Avoid zeroing out recorded samples if underrun
  Atomically send initial stream states
  Use a #define for the stream rate
  Do not send QUBES_PA_SINK_UNCORK_CMD on overrun
  Fix error message when spa_format_parse() fails
  Downgrade unknown ID errors to warnings
  Reduce usage of confusing 'direction' flag
  Cleanup license metadata
  Obtain rate_match and position SPA IOs
  ...

.gitignore

@@ -8,7 +8,8 @@ xf86-input-mfndev/config.h.in
 xf86-input-mfndev/depcomp
 xf86-input-mfndev/ltmain.sh
 xf86-qubes-common/libxf86-qubes-common.so
-pipewire/qubes-pw-module.so
+/pipewire/qubes-pw-module.so
+/pipewire/pw-module-run
 *.dep
 /gui-agent/qubes-gui
 /gui-common/qubes-gui-runuser

debian/control

@@ -121,10 +121,10 @@ Depends:
 Conflicts: pulseaudio-qubes
 Recommends: pipewire-pulse
 Description: PipeWire module to enable sound support in Qubes VM
- Experimental PipeWire module to enable sound support in Qubes VMs.
- Unlike the PulseAudio support in the pulseaudio-qubes package, this
- works with the stock PipeWire service and does not depend on internal
- PipeWire headers.  It is also less code.
+ PipeWire module to enable sound support in Qubes VMs.  Unlike the
+ PulseAudio support in the pulseaudio-qubes package, this works with
+ the stock PipeWire service and does not depend on internal
+ PipeWire headers.
 
 Package: qubes-gui-agent-xfce
 Architecture: any

pipewire/30_qubes.conf

@@ -3,27 +3,40 @@ context.properties = {
    # experiencing a bunch of overruns or underruns.
    #default.clock.min-quantum = 512
 
-   # The Qubes PipeWire module requires a buffer size to be provided.
-   # The record buffer size comes from the org.qubes-os.record-buffer-size
-   # property, and the playback buffer size comes from the
-   # org.qubes-os.record-buffer-size property.  If either of these
-   # properties is missing, the value of org.qubes-os.vchan-buffer-size is
-   # used as a default.
-   #org.qubes-os.vchan-buffer-size = 32768
+   # Set the allowed audio rates to work around problems with Firefox
+   default.clock.allowed-rates = [ 44100 48000 ]
 
-   # Use a smaller buffer size for both recording and playback.
-   #org.qubes-os.vchan-buffer-size = 16384;
+   # Default size of the recording buffer in bytes.  This is very large
+   # because a larger buffer only wastes some memory, whereas a small
+   # buffer risks overruns in the audio daemon (pacat-simple-vchan).
+   org.qubes-os.record.buffer-size = 1048576
 
-   # Use a larger buffer size for recording only
-   #org.qubes-os.record-buffer-size = 65536
+   # Default size of the playback buffer in bytes.  This is smaller
+   # because a large buffer provides less benefit here: it is much more
+   # likely for the audio daemon to underrun (not be able to obtain
+   # enough samples) than for this module to overrun (run out of space).
+   org.qubes-os.playback.buffer-size = 65536
 
-   # Use a smaller buffer size for playback only
-   #org.qubes-os.playback-buffer-size = 16384
+   # The Qubes PipeWire module tries to keep the amount of data buffered
+   # in each vchan roughly constant.  These parameters set this amount.
+   # Note that these parameters have units of *bytes*, not samples!
+   # FIXME: use samples instead.
+
+   # Target number of bytes in the playback vchan
+   org.qubes-os.playback.target-buffer = 8192
+
+   # Target number of bytes in the recording vchan
+   org.qubes-os.record.target-buffer = 8192
 }
 
 context.modules = [
     {
         name = libpipewire-module-qubes
+        # Arguments passed to the module override context properties.
+        # To reduce xruns at the expense of increased recording latency,
+        # one could add:
+        #
+        # args = { org.qubes-os.record.target-buffer = 16384 }
         args = { }
     }
 ]

pipewire/Makefile

@@ -6,15 +6,19 @@ extra_ldflags :=  $(shell pkg-config --libs libpipewire-0.3 vchan-xen) -lqubesdb
 CFLAGS += $(extra_cflags)
 LDLIBS += $(extra_ldflags)
 LDFLAGS += -ggdb -Wl,--no-as-needed,--no-allow-shlib-undefined,-z,relro,-z,now
-qubes-pw-module.so: build/qubes-pw-module.o | Makefile
+all: qubes-pw-module.so pw-module-run
+%.so: build/%.o | Makefile
 	@mkdir -p -m 0700 -- build
 	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ -shared $(LDLIBS)
+%: build/%.o | Makefile
+	@mkdir -p -m 0700 -- build
+	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LDLIBS)
 
 build/%.o: %.c Makefile
 	@mkdir -p -m 0700 -- build
 	$(CC) $(CPPFLAGS) $(CFLAGS) -c -o $@ $< -MP -MD -MF $@.dep
 
-.PHONY: clean
+.PHONY: clean all .PHONY
 clean:
 	rm -rf -- build
 -include build/*.o.dep

pipewire/pw-module-run.c

@@ -0,0 +1,41 @@
+/* SPDX-FileCopyrightText: Copyright © 2021-2023 Wim Taymans */
+/* SPDX-FileCopyrightText: Copyright © 2021-2023 Demi Marie Obenour */
+/* SPDX-License-Identifier: MIT */
+/* C11 headers */
+#include <stddef.h>
+#include <stdlib.h>
+
+/* glibc headers */
+#include <err.h>
+
+#include <pipewire/pipewire.h>
+#include <pipewire/impl-module.h>
+
+int main(int argc, char **argv)
+{
+    pw_init(&argc, &argv);
+    if (argc < 3 || (argc & 1) == 0)
+        errx(1, "Usage: module-loader MODULE ARGS [MODULE ARGS...]\nTotal number of arguments must be even.");
+    struct pw_main_loop *loop = pw_main_loop_new(NULL);
+    if (!loop)
+        err(1, "pw_main_loop_new");
+    struct pw_context *context = pw_context_new(pw_main_loop_get_loop(loop), NULL, 0);
+    if (!context)
+        err(1, "pw_context_new");
+    struct pw_impl_module **modules = calloc(argc >> 1, sizeof(*modules));
+    if (!modules)
+        err(1, "calloc(%d, %zu)", argc, sizeof(*modules));
+    for (int i = 1; i < argc - 1; i += 2) {
+        if ((modules[i / 2] = pw_context_load_module(context, argv[i], argv[i + 1], NULL)) == NULL)
+            err(1, "pw_context_load_module");
+    }
+    int e = pw_main_loop_run(loop);
+    if (e < 0) {
+        errno = -e;
+        err(1, "pw_main_loop_run()");
+    }
+    pw_context_destroy(context);
+    pw_main_loop_destroy(loop);
+
+    return 0;
+}