1 /*
2  * Copyright 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "AudioStreamBuilder"
18 //#define LOG_NDEBUG 0
19 #include <utils/Log.h>
20 
21 #include <new>
22 #include <stdint.h>
23 
24 #include <aaudio/AAudio.h>
25 #include <aaudio/AAudioTesting.h>
26 
27 #include "binding/AAudioBinderClient.h"
28 #include "client/AudioStreamInternalCapture.h"
29 #include "client/AudioStreamInternalPlay.h"
30 #include "core/AudioStream.h"
31 #include "core/AudioStreamBuilder.h"
32 #include "legacy/AudioStreamRecord.h"
33 #include "legacy/AudioStreamTrack.h"
34 
35 using namespace aaudio;
36 
37 #define AAUDIO_MMAP_POLICY_DEFAULT             AAUDIO_POLICY_NEVER
38 #define AAUDIO_MMAP_EXCLUSIVE_POLICY_DEFAULT   AAUDIO_POLICY_NEVER
39 
40 // These values are for a pre-check before we ask the lower level service to open a stream.
41 // So they are just outside the maximum conceivable range of value,
42 // on the edge of being ridiculous.
43 // TODO These defines should be moved to a central place in audio.
44 #define SAMPLES_PER_FRAME_MIN        1
45 // TODO Remove 8 channel limitation.
46 #define SAMPLES_PER_FRAME_MAX        FCC_8
47 #define SAMPLE_RATE_HZ_MIN           8000
48 // HDMI supports up to 32 channels at 1536000 Hz.
49 #define SAMPLE_RATE_HZ_MAX           1600000
50 #define FRAMES_PER_DATA_CALLBACK_MIN 1
51 #define FRAMES_PER_DATA_CALLBACK_MAX (1024 * 1024)
52 
53 /*
54  * AudioStreamBuilder
55  */
AudioStreamBuilder()56 AudioStreamBuilder::AudioStreamBuilder() {
57 }
58 
~AudioStreamBuilder()59 AudioStreamBuilder::~AudioStreamBuilder() {
60 }
61 
builder_createStream(aaudio_direction_t direction,aaudio_sharing_mode_t sharingMode,bool tryMMap,AudioStream ** audioStreamPtr)62 static aaudio_result_t builder_createStream(aaudio_direction_t direction,
63                                          aaudio_sharing_mode_t sharingMode,
64                                          bool tryMMap,
65                                          AudioStream **audioStreamPtr) {
66     *audioStreamPtr = nullptr;
67     aaudio_result_t result = AAUDIO_OK;
68 
69     switch (direction) {
70 
71         case AAUDIO_DIRECTION_INPUT:
72             if (tryMMap) {
73                 *audioStreamPtr = new AudioStreamInternalCapture(AAudioBinderClient::getInstance(),
74                                                                  false);
75             } else {
76                 *audioStreamPtr = new AudioStreamRecord();
77             }
78             break;
79 
80         case AAUDIO_DIRECTION_OUTPUT:
81             if (tryMMap) {
82                 *audioStreamPtr = new AudioStreamInternalPlay(AAudioBinderClient::getInstance(),
83                                                               false);
84             } else {
85                 *audioStreamPtr = new AudioStreamTrack();
86             }
87             break;
88 
89         default:
90             ALOGE("%s() bad direction = %d", __func__, direction);
91             result = AAUDIO_ERROR_ILLEGAL_ARGUMENT;
92     }
93     return result;
94 }
95 
96 // Try to open using MMAP path if that is allowed.
97 // Fall back to Legacy path if MMAP not available.
98 // Exact behavior is controlled by MMapPolicy.
build(AudioStream ** streamPtr)99 aaudio_result_t AudioStreamBuilder::build(AudioStream** streamPtr) {
100     AudioStream *audioStream = nullptr;
101     if (streamPtr == nullptr) {
102         ALOGE("%s() streamPtr is null", __func__);
103         return AAUDIO_ERROR_NULL;
104     }
105     *streamPtr = nullptr;
106 
107     aaudio_result_t result = validate();
108     if (result != AAUDIO_OK) {
109         return result;
110     }
111 
112     // The API setting is the highest priority.
113     aaudio_policy_t mmapPolicy = AAudio_getMMapPolicy();
114     // If not specified then get from a system property.
115     if (mmapPolicy == AAUDIO_UNSPECIFIED) {
116         mmapPolicy = AAudioProperty_getMMapPolicy();
117     }
118     // If still not specified then use the default.
119     if (mmapPolicy == AAUDIO_UNSPECIFIED) {
120         mmapPolicy = AAUDIO_MMAP_POLICY_DEFAULT;
121     }
122 
123     int32_t mapExclusivePolicy = AAudioProperty_getMMapExclusivePolicy();
124     if (mapExclusivePolicy == AAUDIO_UNSPECIFIED) {
125         mapExclusivePolicy = AAUDIO_MMAP_EXCLUSIVE_POLICY_DEFAULT;
126     }
127 
128     aaudio_sharing_mode_t sharingMode = getSharingMode();
129     if ((sharingMode == AAUDIO_SHARING_MODE_EXCLUSIVE)
130         && (mapExclusivePolicy == AAUDIO_POLICY_NEVER)) {
131         ALOGD("%s() EXCLUSIVE sharing mode not supported. Use SHARED.", __func__);
132         sharingMode = AAUDIO_SHARING_MODE_SHARED;
133         setSharingMode(sharingMode);
134     }
135 
136     bool allowMMap = mmapPolicy != AAUDIO_POLICY_NEVER;
137     bool allowLegacy = mmapPolicy != AAUDIO_POLICY_ALWAYS;
138 
139     // TODO Support other performance settings in MMAP mode.
140     // Disable MMAP if low latency not requested.
141     if (getPerformanceMode() != AAUDIO_PERFORMANCE_MODE_LOW_LATENCY) {
142         ALOGD("%s() MMAP not available because AAUDIO_PERFORMANCE_MODE_LOW_LATENCY not used.",
143               __func__);
144         allowMMap = false;
145     }
146 
147     // SessionID and Effects are only supported in Legacy mode.
148     if (getSessionId() != AAUDIO_SESSION_ID_NONE) {
149         ALOGD("%s() MMAP not available because sessionId used.", __func__);
150         allowMMap = false;
151     }
152 
153     result = builder_createStream(getDirection(), sharingMode, allowMMap, &audioStream);
154     if (result == AAUDIO_OK) {
155         // Open the stream using the parameters from the builder.
156         result = audioStream->open(*this);
157         if (result == AAUDIO_OK) {
158             *streamPtr = audioStream;
159         } else {
160             bool isMMap = audioStream->isMMap();
161             delete audioStream;
162             audioStream = nullptr;
163 
164             if (isMMap && allowLegacy) {
165                 ALOGV("%s() MMAP stream did not open so try Legacy path", __func__);
166                 // If MMAP stream failed to open then TRY using a legacy stream.
167                 result = builder_createStream(getDirection(), sharingMode,
168                                               false, &audioStream);
169                 if (result == AAUDIO_OK) {
170                     result = audioStream->open(*this);
171                     if (result == AAUDIO_OK) {
172                         *streamPtr = audioStream;
173                     } else {
174                         delete audioStream;
175                     }
176                 }
177             }
178         }
179     }
180 
181     return result;
182 }
183 
validate() const184 aaudio_result_t AudioStreamBuilder::validate() const {
185 
186     // Check for values that are ridiculously out of range to prevent math overflow exploits.
187     // The service will do a better check.
188     aaudio_result_t result = AAudioStreamParameters::validate();
189     if (result != AAUDIO_OK) {
190         return result;
191     }
192 
193     switch (mPerformanceMode) {
194         case AAUDIO_PERFORMANCE_MODE_NONE:
195         case AAUDIO_PERFORMANCE_MODE_POWER_SAVING:
196         case AAUDIO_PERFORMANCE_MODE_LOW_LATENCY:
197             break;
198         default:
199             ALOGE("illegal performanceMode = %d", mPerformanceMode);
200             return AAUDIO_ERROR_ILLEGAL_ARGUMENT;
201             // break;
202     }
203 
204     // Prevent ridiculous values from causing problems.
205     if (mFramesPerDataCallback != AAUDIO_UNSPECIFIED
206         && (mFramesPerDataCallback < FRAMES_PER_DATA_CALLBACK_MIN
207             || mFramesPerDataCallback > FRAMES_PER_DATA_CALLBACK_MAX)) {
208         ALOGE("framesPerDataCallback out of range = %d",
209               mFramesPerDataCallback);
210         return AAUDIO_ERROR_OUT_OF_RANGE;
211     }
212 
213     return AAUDIO_OK;
214 }
215