Support use_alsa==0 on Linux

This moves the ALSA audio code from media/audio/linux to
media/audio/alsa and splits Linux's CreateAudioManager() into a new
file. This function chooses which AudioManager subclass to use on Linux.

When use_alsa==0 on Linux, the fallback audio manager is changed from
ALSA to a new fake implementation that always has an empty set of devices
and will only return fake streams.

This allows us to compile with no audio support on Linux. In particular,
we can compile for targets that don't have the ALSA libraries available.
Obviously, it's not (yet) possible to play audio in this configuration.

BUG=318315, 318413

Review URL: https://codereview.chromium.org/89793003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237696 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 173 insertions, 0 deletions

diff --git a/media/audio/alsa/alsa_wrapper.cc b/media/audio/alsa/alsa_wrapper.cc
new file mode 100644
index 0000000..969f3c4
--- /dev/null
+++ b/media/audio/alsa/alsa_wrapper.cc
@@ -0,0 +1,173 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/audio/alsa/alsa_wrapper.h"
+
+#include <alsa/asoundlib.h>
+
+namespace media {
+
+AlsaWrapper::AlsaWrapper() {
+}
+
+AlsaWrapper::~AlsaWrapper() {
+}
+
+int AlsaWrapper::PcmOpen(snd_pcm_t** handle, const char* name,
+                         snd_pcm_stream_t stream, int mode) {
+  return snd_pcm_open(handle, name, stream, mode);
+}
+
+int AlsaWrapper::DeviceNameHint(int card, const char* iface, void*** hints) {
+  return snd_device_name_hint(card, iface, hints);
+}
+
+char* AlsaWrapper::DeviceNameGetHint(const void* hint, const char* id) {
+  return snd_device_name_get_hint(hint, id);
+}
+
+int AlsaWrapper::DeviceNameFreeHint(void** hints) {
+  return snd_device_name_free_hint(hints);
+}
+
+int AlsaWrapper::CardNext(int* rcard) {
+  return snd_card_next(rcard);
+}
+
+int AlsaWrapper::PcmClose(snd_pcm_t* handle) {
+  return snd_pcm_close(handle);
+}
+
+int AlsaWrapper::PcmPrepare(snd_pcm_t* handle) {
+  return snd_pcm_prepare(handle);
+}
+
+int AlsaWrapper::PcmDrop(snd_pcm_t* handle) {
+  return snd_pcm_drop(handle);
+}
+
+int AlsaWrapper::PcmDelay(snd_pcm_t* handle, snd_pcm_sframes_t* delay) {
+  return snd_pcm_delay(handle, delay);
+}
+
+snd_pcm_sframes_t AlsaWrapper::PcmWritei(snd_pcm_t* handle,
+                                         const void* buffer,
+                                         snd_pcm_uframes_t size) {
+  return snd_pcm_writei(handle, buffer, size);
+}
+
+snd_pcm_sframes_t AlsaWrapper::PcmReadi(snd_pcm_t* handle,
+                                        void* buffer,
+                                        snd_pcm_uframes_t size) {
+  return snd_pcm_readi(handle, buffer, size);
+}
+
+int AlsaWrapper::PcmRecover(snd_pcm_t* handle, int err, int silent) {
+  return snd_pcm_recover(handle, err, silent);
+}
+
+const char* AlsaWrapper::PcmName(snd_pcm_t* handle) {
+  return snd_pcm_name(handle);
+}
+
+int AlsaWrapper::PcmSetParams(snd_pcm_t* handle, snd_pcm_format_t format,
+                              snd_pcm_access_t access, unsigned int channels,
+                              unsigned int rate, int soft_resample,
+                              unsigned int latency) {
+  return snd_pcm_set_params(handle,
+                            format,
+                            access,
+                            channels,
+                            rate,
+                            soft_resample,
+                            latency);
+}
+
+int AlsaWrapper::PcmGetParams(snd_pcm_t* handle, snd_pcm_uframes_t* buffer_size,
+                              snd_pcm_uframes_t* period_size) {
+  return snd_pcm_get_params(handle, buffer_size, period_size);
+}
+
+snd_pcm_sframes_t AlsaWrapper::PcmAvailUpdate(snd_pcm_t* handle) {
+  return snd_pcm_avail_update(handle);
+}
+
+snd_pcm_state_t AlsaWrapper::PcmState(snd_pcm_t* handle) {
+  return snd_pcm_state(handle);
+}
+
+const char* AlsaWrapper::StrError(int errnum) {
+  return snd_strerror(errnum);
+}
+
+int AlsaWrapper::PcmStart(snd_pcm_t* handle) {
+  return snd_pcm_start(handle);
+}
+
+int AlsaWrapper::MixerOpen(snd_mixer_t** mixer, int mode) {
+  return snd_mixer_open(mixer, mode);
+}
+
+int AlsaWrapper::MixerAttach(snd_mixer_t* mixer, const char* name) {
+  return snd_mixer_attach(mixer, name);
+}
+
+int AlsaWrapper::MixerElementRegister(snd_mixer_t* mixer,
+                                      struct snd_mixer_selem_regopt* options,
+                                      snd_mixer_class_t** classp) {
+  return snd_mixer_selem_register(mixer, options, classp);
+}
+
+void AlsaWrapper::MixerFree(snd_mixer_t* mixer) {
+  snd_mixer_free(mixer);
+}
+
+int AlsaWrapper::MixerDetach(snd_mixer_t* mixer, const char* name) {
+  return snd_mixer_detach(mixer, name);
+}
+
+int AlsaWrapper::MixerClose(snd_mixer_t* mixer) {
+  return snd_mixer_close(mixer);
+}
+
+int AlsaWrapper::MixerLoad(snd_mixer_t* mixer) {
+  return snd_mixer_load(mixer);
+}
+
+snd_mixer_elem_t* AlsaWrapper::MixerFirstElem(snd_mixer_t* mixer) {
+  return snd_mixer_first_elem(mixer);
+}
+
+snd_mixer_elem_t* AlsaWrapper::MixerNextElem(snd_mixer_elem_t* elem) {
+  return snd_mixer_elem_next(elem);
+}
+
+int AlsaWrapper::MixerSelemIsActive(snd_mixer_elem_t* elem) {
+  return snd_mixer_selem_is_active(elem);
+}
+
+const char* AlsaWrapper::MixerSelemName(snd_mixer_elem_t* elem) {
+  return snd_mixer_selem_get_name(elem);
+}
+
+int AlsaWrapper::MixerSelemSetCaptureVolumeAll(
+    snd_mixer_elem_t* elem, long value) {
+  return snd_mixer_selem_set_capture_volume_all(elem, value);
+}
+
+int AlsaWrapper::MixerSelemGetCaptureVolume(
+    snd_mixer_elem_t* elem, snd_mixer_selem_channel_id_t channel, long* value) {
+  return snd_mixer_selem_get_capture_volume(elem, channel, value);
+}
+
+int AlsaWrapper::MixerSelemHasCaptureVolume(snd_mixer_elem_t* elem) {
+  return snd_mixer_selem_has_capture_volume(elem);
+}
+
+int AlsaWrapper::MixerSelemGetCaptureVolumeRange(snd_mixer_elem_t* elem,
+                                                 long* min, long* max) {
+  return snd_mixer_selem_get_capture_volume_range(elem, min, max);
+}
+
+}  // namespace media