1 /*
2 * Copyright 2018 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 #include <dlfcn.h>
18 #include <cstdio>
19 #include "Trace.h"
20 #include "OboeDebug.h"
21
22 static char buffer[256];
23
24 // Tracing functions
25 static void *(*ATrace_beginSection)(const char *sectionName);
26
27 static void *(*ATrace_endSection)();
28
29 typedef void *(*fp_ATrace_beginSection)(const char *sectionName);
30
31 typedef void *(*fp_ATrace_endSection)();
32
33 bool Trace::mIsTracingSupported = false;
34
beginSection(const char * format,...)35 void Trace::beginSection(const char *format, ...){
36
37 if (mIsTracingSupported) {
38 va_list va;
39 va_start(va, format);
40 vsprintf(buffer, format, va);
41 ATrace_beginSection(buffer);
42 va_end(va);
43 } else {
44 LOGE("Tracing is either not initialized (call Trace::initialize()) "
45 "or not supported on this device");
46 }
47 }
48
endSection()49 void Trace::endSection() {
50
51 if (mIsTracingSupported) {
52 ATrace_endSection();
53 }
54 }
55
initialize()56 void Trace::initialize() {
57
58 // Using dlsym allows us to use tracing on API 21+ without needing android/trace.h which wasn't
59 // published until API 23
60 void *lib = dlopen("libandroid.so", RTLD_NOW | RTLD_LOCAL);
61 if (lib == nullptr) {
62 LOGE("Could not open libandroid.so to dynamically load tracing symbols");
63 } else {
64 ATrace_beginSection =
65 reinterpret_cast<fp_ATrace_beginSection >(
66 dlsym(lib, "ATrace_beginSection"));
67 ATrace_endSection =
68 reinterpret_cast<fp_ATrace_endSection >(
69 dlsym(lib, "ATrace_endSection"));
70
71 if (ATrace_beginSection != nullptr && ATrace_endSection != nullptr){
72 mIsTracingSupported = true;
73 }
74 }
75 }