1 /*
2  * Copyright (C) 2013 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 #ifndef ANDROID_SERVERS_CAMERA_TRACES_H_
18 #define ANDROID_SERVERS_CAMERA_TRACES_H_
19 
20 #include <utils/Errors.h>
21 #include <utils/String16.h>
22 #include <utils/Vector.h>
23 
24 namespace android {
25 namespace camera3 {
26 
27 struct CameraTracesImpl;
28 
29 // Collect a list of the process's stack traces
30 class CameraTraces {
31 public:
32     /**
33      * Save the current stack trace for each thread in the process. At most
34      * MAX_TRACES will be saved, after which the oldest traces will be discarded.
35      *
36      * <p>Use CameraTraces::dump to print out the traces.</p>
37      */
38     static void     saveTrace();
39 
40     /**
41      * Prints all saved traces to the specified file descriptor.
42      *
43      * <p>Each line is indented by DUMP_INDENT spaces.</p>
44      */
45     static status_t dump(int fd, const Vector<String16>& args);
46 
47 private:
48     enum {
49         // Don't collect more than 100 traces. Discard oldest.
50         MAX_TRACES = 100,
51 
52         // Insert 2 spaces when dumping the traces
53         DUMP_INDENT = 2,
54     };
55 
56     CameraTraces();
57     ~CameraTraces();
58     CameraTraces(CameraTraces& rhs);
59 
60     static CameraTracesImpl& sImpl;
61 }; // class CameraTraces
62 
63 }; // namespace camera3
64 }; // namespace android
65 
66 #endif // ANDROID_SERVERS_CAMERA_TRACES_H_
67