1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
// Copyright (c) 2012 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/pulse/pulse_output.h"
#include <pulse/pulseaudio.h>
#include "base/message_loop/message_loop.h"
#include "media/audio/audio_manager_base.h"
#include "media/audio/audio_parameters.h"
#include "media/audio/pulse/pulse_util.h"
namespace media {
using pulse::AutoPulseLock;
using pulse::WaitForOperationCompletion;
// static, pa_stream_notify_cb
void PulseAudioOutputStream::StreamNotifyCallback(pa_stream* s, void* p_this) {
PulseAudioOutputStream* stream = static_cast<PulseAudioOutputStream*>(p_this);
// Forward unexpected failures to the AudioSourceCallback if available. All
// these variables are only modified under pa_threaded_mainloop_lock() so this
// should be thread safe.
if (s && stream->source_callback_ &&
pa_stream_get_state(s) == PA_STREAM_FAILED) {
stream->source_callback_->OnError(stream);
}
pa_threaded_mainloop_signal(stream->pa_mainloop_, 0);
}
// static, pa_stream_request_cb_t
void PulseAudioOutputStream::StreamRequestCallback(pa_stream* s, size_t len,
void* p_this) {
// Fulfill write request; must always result in a pa_stream_write() call.
static_cast<PulseAudioOutputStream*>(p_this)->FulfillWriteRequest(len);
}
PulseAudioOutputStream::PulseAudioOutputStream(const AudioParameters& params,
AudioManagerBase* manager)
: params_(params),
manager_(manager),
pa_context_(NULL),
pa_mainloop_(NULL),
pa_stream_(NULL),
volume_(1.0f),
source_callback_(NULL) {
DCHECK(manager_->GetMessageLoop()->BelongsToCurrentThread());
CHECK(params_.IsValid());
audio_bus_ = AudioBus::Create(params_);
}
PulseAudioOutputStream::~PulseAudioOutputStream() {
// All internal structures should already have been freed in Close(), which
// calls AudioManagerBase::ReleaseOutputStream() which deletes this object.
DCHECK(!pa_stream_);
DCHECK(!pa_context_);
DCHECK(!pa_mainloop_);
}
bool PulseAudioOutputStream::Open() {
DCHECK(manager_->GetMessageLoop()->BelongsToCurrentThread());
return pulse::CreateOutputStream(&pa_mainloop_, &pa_context_, &pa_stream_,
params_, &StreamNotifyCallback,
&StreamRequestCallback, this);
}
void PulseAudioOutputStream::Reset() {
if (!pa_mainloop_) {
DCHECK(!pa_stream_);
DCHECK(!pa_context_);
return;
}
{
AutoPulseLock auto_lock(pa_mainloop_);
// Close the stream.
if (pa_stream_) {
// Ensure all samples are played out before shutdown.
pa_operation* operation = pa_stream_flush(
pa_stream_, &pulse::StreamSuccessCallback, pa_mainloop_);
WaitForOperationCompletion(pa_mainloop_, operation);
// Release PulseAudio structures.
pa_stream_disconnect(pa_stream_);
pa_stream_set_write_callback(pa_stream_, NULL, NULL);
pa_stream_set_state_callback(pa_stream_, NULL, NULL);
pa_stream_unref(pa_stream_);
pa_stream_ = NULL;
}
if (pa_context_) {
pa_context_disconnect(pa_context_);
pa_context_set_state_callback(pa_context_, NULL, NULL);
pa_context_unref(pa_context_);
pa_context_ = NULL;
}
}
pa_threaded_mainloop_stop(pa_mainloop_);
pa_threaded_mainloop_free(pa_mainloop_);
pa_mainloop_ = NULL;
}
void PulseAudioOutputStream::Close() {
DCHECK(manager_->GetMessageLoop()->BelongsToCurrentThread());
Reset();
// Signal to the manager that we're closed and can be removed.
// This should be the last call in the function as it deletes "this".
manager_->ReleaseOutputStream(this);
}
void PulseAudioOutputStream::FulfillWriteRequest(size_t requested_bytes) {
int bytes_remaining = requested_bytes;
while (bytes_remaining > 0) {
void* buffer = NULL;
size_t bytes_to_fill = params_.GetBytesPerBuffer();
CHECK_GE(pa_stream_begin_write(pa_stream_, &buffer, &bytes_to_fill), 0);
CHECK_EQ(bytes_to_fill, static_cast<size_t>(params_.GetBytesPerBuffer()));
int frames_filled = 0;
if (source_callback_) {
uint32 hardware_delay = pulse::GetHardwareLatencyInBytes(
pa_stream_, params_.sample_rate(),
params_.GetBytesPerFrame());
frames_filled = source_callback_->OnMoreData(
audio_bus_.get(), AudioBuffersState(0, hardware_delay));
}
// Zero any unfilled data so it plays back as silence.
if (frames_filled < audio_bus_->frames()) {
audio_bus_->ZeroFramesPartial(
frames_filled, audio_bus_->frames() - frames_filled);
}
// Note: If this ever changes to output raw float the data must be clipped
// and sanitized since it may come from an untrusted source such as NaCl.
audio_bus_->Scale(volume_);
audio_bus_->ToInterleaved(
audio_bus_->frames(), params_.bits_per_sample() / 8, buffer);
if (pa_stream_write(pa_stream_, buffer, bytes_to_fill, NULL, 0LL,
PA_SEEK_RELATIVE) < 0) {
if (source_callback_) {
source_callback_->OnError(this);
}
}
bytes_remaining -= bytes_to_fill;
}
}
void PulseAudioOutputStream::Start(AudioSourceCallback* callback) {
DCHECK(manager_->GetMessageLoop()->BelongsToCurrentThread());
CHECK(callback);
CHECK(pa_stream_);
AutoPulseLock auto_lock(pa_mainloop_);
// Ensure the context and stream are ready.
if (pa_context_get_state(pa_context_) != PA_CONTEXT_READY &&
pa_stream_get_state(pa_stream_) != PA_STREAM_READY) {
callback->OnError(this);
return;
}
source_callback_ = callback;
// Uncork (resume) the stream.
pa_operation* operation = pa_stream_cork(
pa_stream_, 0, &pulse::StreamSuccessCallback, pa_mainloop_);
WaitForOperationCompletion(pa_mainloop_, operation);
}
void PulseAudioOutputStream::Stop() {
DCHECK(manager_->GetMessageLoop()->BelongsToCurrentThread());
// Cork (pause) the stream. Waiting for the main loop lock will ensure
// outstanding callbacks have completed.
AutoPulseLock auto_lock(pa_mainloop_);
// Set |source_callback_| to NULL so all FulfillWriteRequest() calls which may
// occur while waiting on the flush and cork exit immediately.
source_callback_ = NULL;
// Flush the stream prior to cork, doing so after will cause hangs. Write
// callbacks are suspended while inside pa_threaded_mainloop_lock() so this
// is all thread safe.
pa_operation* operation = pa_stream_flush(
pa_stream_, &pulse::StreamSuccessCallback, pa_mainloop_);
WaitForOperationCompletion(pa_mainloop_, operation);
operation = pa_stream_cork(pa_stream_, 1, &pulse::StreamSuccessCallback,
pa_mainloop_);
WaitForOperationCompletion(pa_mainloop_, operation);
}
void PulseAudioOutputStream::SetVolume(double volume) {
DCHECK(manager_->GetMessageLoop()->BelongsToCurrentThread());
volume_ = static_cast<float>(volume);
}
void PulseAudioOutputStream::GetVolume(double* volume) {
DCHECK(manager_->GetMessageLoop()->BelongsToCurrentThread());
*volume = volume_;
}
} // namespace media
|
