1 /*
2 * Copyright (C) 2016 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 "HidlInternal"
18
19 #include <hidl/HidlInternal.h>
20
21 #ifdef __ANDROID__
22 #include <android/api-level.h>
23 #endif
24 #include <android-base/logging.h>
25 #include <android-base/properties.h>
26 #include <android-base/stringprintf.h>
27
28 #ifdef LIBHIDL_TARGET_DEBUGGABLE
29 #include <dirent.h>
30 #include <dlfcn.h>
31 #include <link.h>
32 #include <utils/misc.h>
33 #include <regex>
34
35 extern "C" __attribute__((weak)) void __sanitizer_cov_dump();
36
37 const char kGcovPrefixEnvVar[] = "GCOV_PREFIX";
38 const char kGcovPrefixOverrideEnvVar[] = "GCOV_PREFIX_OVERRIDE";
39 const char kGcovPrefixPath[] = "/data/misc/trace/";
40 const char kSysPropHalCoverage[] = "hal.coverage.enable";
41 #if defined(__LP64__)
42 const char kSysPropInstrumentationPath[] = "hal.instrumentation.lib.path.64";
43 #else
44 const char kSysPropInstrumentationPath[] = "hal.instrumentation.lib.path.32";
45 #endif
46 #endif // LIBHIDL_TARGET_DEBUGGABLE
47
48 namespace android {
49 namespace hardware {
50 namespace details {
51
logAlwaysFatal(const char * message)52 void logAlwaysFatal(const char* message) {
53 LOG(FATAL) << message;
54 }
55
getVndkSpHwPath(const char * lib)56 std::string getVndkSpHwPath(const char* lib) {
57 static std::string vndk_version = base::GetProperty("ro.vndk.version", "");
58 #ifdef __ANDROID__
59 static int api_level = android_get_device_api_level();
60 if (api_level >= __ANDROID_API_R__) {
61 return android::base::StringPrintf("/apex/com.android.vndk.v%s/%s/hw/",
62 vndk_version.c_str(), lib);
63 }
64 #endif
65 return android::base::StringPrintf("/system/%s/vndk-sp-%s/hw/", lib, vndk_version.c_str());
66 }
67
68 // ----------------------------------------------------------------------
69 // HidlInstrumentor implementation.
HidlInstrumentor(const std::string & package,const std::string & interface)70 HidlInstrumentor::HidlInstrumentor(const std::string& package, const std::string& interface)
71 : mEnableInstrumentation(false),
72 mInstrumentationLibPackage(package),
73 mInterfaceName(interface) {
74 #ifdef LIBHIDL_TARGET_DEBUGGABLE
75 configureInstrumentation(false);
76 if (__sanitizer_cov_dump != nullptr) {
77 ::android::add_sysprop_change_callback(
78 []() {
79 bool enableCoverage = base::GetBoolProperty(kSysPropHalCoverage, false);
80 if (enableCoverage) {
81 __sanitizer_cov_dump();
82 }
83 },
84 0);
85 }
86 if (base::GetBoolProperty("ro.vts.coverage", false)) {
87 const char* prefixOverride = getenv(kGcovPrefixOverrideEnvVar);
88 if (prefixOverride == nullptr || strcmp(prefixOverride, "true") != 0) {
89 const std::string gcovPath = kGcovPrefixPath + std::to_string(getpid());
90 setenv(kGcovPrefixEnvVar, gcovPath.c_str(), true /* overwrite */);
91 }
92 ::android::add_sysprop_change_callback(
93 []() {
94 const bool enableCoverage = base::GetBoolProperty(kSysPropHalCoverage, false);
95 if (enableCoverage) {
96 dl_iterate_phdr(
97 [](struct dl_phdr_info* info, size_t /* size */, void* /* data */) {
98 if (strlen(info->dlpi_name) == 0) return 0;
99
100 void* handle = dlopen(info->dlpi_name, RTLD_LAZY);
101 if (handle == nullptr) {
102 LOG(INFO) << "coverage dlopen failed: " << dlerror();
103 return 0;
104 }
105 void (*flush)() = (void (*)())dlsym(handle, "__gcov_flush");
106 if (flush == nullptr) {
107 return 0;
108 }
109 flush();
110 return 0;
111 },
112 nullptr /* data */);
113 }
114 },
115 0 /* priority */);
116 }
117 #endif
118 }
119
~HidlInstrumentor()120 HidlInstrumentor::~HidlInstrumentor() {}
121
configureInstrumentation(bool log)122 void HidlInstrumentor::configureInstrumentation(bool log) {
123 mEnableInstrumentation = base::GetBoolProperty("hal.instrumentation.enable", false);
124 if (mEnableInstrumentation) {
125 if (log) {
126 LOG(INFO) << "Enable instrumentation.";
127 }
128 mInstrumentationCallbacks.clear();
129 registerInstrumentationCallbacks(&mInstrumentationCallbacks);
130 } else {
131 if (log) {
132 LOG(INFO) << "Disable instrumentation.";
133 }
134 mInstrumentationCallbacks.clear();
135 }
136 }
137
registerInstrumentationCallbacks(std::vector<InstrumentationCallback> * instrumentationCallbacks)138 void HidlInstrumentor::registerInstrumentationCallbacks(
139 std::vector<InstrumentationCallback> *instrumentationCallbacks) {
140 #ifdef LIBHIDL_TARGET_DEBUGGABLE
141 std::vector<std::string> instrumentationLibPaths;
142 const std::string instrumentationLibPath = base::GetProperty(kSysPropInstrumentationPath, "");
143 if (instrumentationLibPath.size() > 0) {
144 instrumentationLibPaths.push_back(instrumentationLibPath);
145 } else {
146 static std::string halLibPathVndkSp = getVndkSpHwPath();
147 #ifndef __ANDROID_VNDK__
148 instrumentationLibPaths.push_back(HAL_LIBRARY_PATH_SYSTEM);
149 #endif
150 instrumentationLibPaths.push_back(halLibPathVndkSp);
151 instrumentationLibPaths.push_back(HAL_LIBRARY_PATH_VENDOR);
152 instrumentationLibPaths.push_back(HAL_LIBRARY_PATH_ODM);
153 }
154
155 for (const auto& path : instrumentationLibPaths) {
156 DIR *dir = opendir(path.c_str());
157 if (dir == nullptr) {
158 LOG(WARNING) << path << " does not exist. ";
159 return;
160 }
161
162 struct dirent *file;
163 while ((file = readdir(dir)) != nullptr) {
164 if (!isInstrumentationLib(file))
165 continue;
166
167 void *handle = dlopen((path + file->d_name).c_str(), RTLD_NOW);
168 char *error;
169 if (handle == nullptr) {
170 LOG(WARNING) << "couldn't load file: " << file->d_name
171 << " error: " << dlerror();
172 continue;
173 }
174
175 dlerror(); /* Clear any existing error */
176
177 using cbFun = void (*)(
178 const InstrumentationEvent,
179 const char *,
180 const char *,
181 const char *,
182 const char *,
183 std::vector<void *> *);
184 std::string package = mInstrumentationLibPackage;
185 for (size_t i = 0; i < package.size(); i++) {
186 if (package[i] == '.') {
187 package[i] = '_';
188 continue;
189 }
190
191 if (package[i] == '@') {
192 package[i] = '_';
193 package.insert(i + 1, "V");
194 continue;
195 }
196 }
197 auto cb = (cbFun)dlsym(handle, ("HIDL_INSTRUMENTATION_FUNCTION_"
198 + package + "_" + mInterfaceName).c_str());
199 if ((error = dlerror()) != nullptr) {
200 LOG(WARNING)
201 << "couldn't find symbol: HIDL_INSTRUMENTATION_FUNCTION_"
202 << package << "_" << mInterfaceName << ", error: " << error;
203 continue;
204 }
205 instrumentationCallbacks->push_back(cb);
206 LOG(INFO) << "Register instrumentation callback from "
207 << file->d_name;
208 }
209 closedir(dir);
210 }
211 #else
212 // No-op for user builds.
213 (void) instrumentationCallbacks;
214 return;
215 #endif
216 }
217
isInstrumentationLib(const dirent * file)218 bool HidlInstrumentor::isInstrumentationLib(const dirent *file) {
219 #ifdef LIBHIDL_TARGET_DEBUGGABLE
220 if (file->d_type != DT_REG) return false;
221 std::cmatch cm;
222 std::regex e("^" + mInstrumentationLibPackage + "(.*).profiler.so$");
223 if (std::regex_match(file->d_name, cm, e)) return true;
224 #else
225 (void) file;
226 #endif
227 return false;
228 }
229
230 } // namespace details
231 } // namespace hardware
232 } // namespace android
233