getService should retry if getting nullptr am: 64ba3d7987
am: d5749ed112
Change-Id: I03b98bb48cdfece7fd56b2aeb89d7683448566e6
diff --git a/generateCpp.cpp b/generateCpp.cpp
index 7529460..bc4b859 100644
--- a/generateCpp.cpp
+++ b/generateCpp.cpp
@@ -156,46 +156,98 @@
out << "// static\n"
<< "::android::sp<" << interfaceName << "> " << interfaceName << "::getService("
- << "const std::string &serviceName, bool getStub) ";
+ << "const std::string &serviceName, const bool getStub) ";
out.block([&] {
out << "::android::sp<" << interfaceName << "> iface = nullptr;\n";
out << "::android::vintf::Transport transport = ::android::hardware::getTransport("
<< interfaceName << "::descriptor, serviceName);\n";
- out.sIf("!getStub && "
- "(transport == ::android::vintf::Transport::HWBINDER || "
- "transport == ::android::vintf::Transport::TOGGLED || "
- "transport == ::android::vintf::Transport::EMPTY)", [&] {
+ // TODO(b/34274385) remove sysprop check
+ out << "const bool vintfHwbinder = (transport == ::android::vintf::Transport::HWBINDER) ||\n"
+ << " (transport == ::android::vintf::Transport::TOGGLED &&\n"
+ << " ::android::hardware::details::blockingHalBinderizationEnabled());\n"
+ << "const bool vintfPassthru = (transport == ::android::vintf::Transport::PASSTHROUGH) ||\n"
+ << " (transport == ::android::vintf::Transport::TOGGLED &&\n"
+ << " !::android::hardware::details::blockingHalBinderizationEnabled());\n"
+ << "const bool vintfEmpty = (transport == ::android::vintf::Transport::EMPTY);\n\n";
+
+ // if (getStub) {
+ // getPassthroughServiceManager()->get only once.
+ // } else {
+ // if (vintfHwbinder) {
+ // while (no alive service) {
+ // waitForHwService
+ // defaultServiceManager()->get
+ // }
+ // } else if (vintfEmpty) {
+ // defaultServiceManager()->get only once.
+ // getPassthroughServiceManager()->get only once.
+ // } else if (vintfPassthru) {
+ // getPassthroughServiceManager()->get only once.
+ // }
+ // }
+
+ out.sFor("bool tried = false; "
+ "!getStub && (vintfHwbinder || (vintfEmpty && !tried)); "
+ "tried = true", [&] {
+
+ // Because this is a for loop, a "continue" statement means
+ // setting tried, and hence "break" for vintfEmpty and
+ // "retry" for vintfHwBinder
+
+ out.sIf("tried", [&] {
+ // sleep only after the first trial.
+ out << "ALOGI(\"getService: retrying in 1s...\");\n"
+ << "sleep(1);\n";
+ }).endl();
+
out << "const ::android::sp<::android::hidl::manager::V1_0::IServiceManager> sm\n";
out.indent(2, [&] {
out << "= ::android::hardware::defaultServiceManager();\n";
});
- out.sIf("sm != nullptr", [&] {
- // TODO(b/34274385) remove sysprop check
- out.sIf("transport == ::android::vintf::Transport::HWBINDER ||"
- "(transport == ::android::vintf::Transport::TOGGLED &&"
- " ::android::hardware::details::blockingHalBinderizationEnabled())", [&]() {
- out << "::android::hardware::details::waitForHwService("
- << interfaceName << "::descriptor" << ", serviceName);\n";
- }).endl();
- out << "::android::hardware::Return<::android::sp<" << gIBaseFqName.cppName() << ">> ret = \n";
- out.indent(2, [&] {
- out << "sm->get(" << interfaceName << "::descriptor" << ", serviceName);\n";
- });
- out.sIf("ret.isOk()", [&] {
- out << "iface = " << interfaceName << "::castFrom(ret);\n";
- out.sIf("iface != nullptr", [&] {
- out << "return iface;\n";
- }).endl();
- }).endl();
+ out.sIf("sm == nullptr", [&] {
+ // hwbinder is not available on this device, so future tries
+ // would also be null. I can only "break" here and
+ // (vintfEmpty) try passthrough or (vintfHwbinder) return nullptr.
+ out << "ALOGE(\"getService: defaultServiceManager() is null\");\n"
+ << "break;\n";
}).endl();
+
+ out.sIf("vintfHwbinder", [&] {
+ out << "::android::hardware::details::waitForHwService("
+ << interfaceName << "::descriptor" << ", serviceName);\n";
+ }).endl();
+
+ out << "::android::hardware::Return<::android::sp<"
+ << gIBaseFqName.cppName() << ">> ret = \n";
+ out.indent(2, [&] {
+ out << "sm->get(" << interfaceName << "::descriptor, serviceName);\n";
+ });
+
+ out.sIf("!ret.isOk()", [&] {
+ // hwservicemanager fails
+ out << "ALOGE(\"getService: defaultServiceManager()->get returns %s\", "
+ << "ret.description().c_str());\n"
+ << "continue;\n";
+ }).endl();
+
+ out << "iface = " << interfaceName << "::castFrom(ret);\n";
+ out.sIf("iface == nullptr", [&] {
+ // 1. race condition. hwservicemanager drops the service
+ // from waitForHwService to here
+ // 2. service is dead (castFrom cannot call interfaceChain)
+ // 3. returned service isn't of correct type; this is a bug
+ // to hwservicemanager or to the service itself (interfaceChain
+ // is not consistent)
+ // In all cases, try again.
+ out << "ALOGW(\"getService: found null interface\");\n"
+ << "continue;\n";
+ }).endl();
+
+ out << "return iface;\n";
}).endl();
- out.sIf("getStub || "
- "transport == ::android::vintf::Transport::PASSTHROUGH || "
- "(transport == ::android::vintf::Transport::TOGGLED &&"
- " !::android::hardware::details::blockingHalBinderizationEnabled()) ||"
- "transport == ::android::vintf::Transport::EMPTY", [&] {
+ out.sIf("getStub || vintfPassthru || vintfEmpty", [&] {
out << "const ::android::sp<::android::hidl::manager::V1_0::IServiceManager> pm\n";
out.indent(2, [&] {
out << "= ::android::hardware::getPassthroughServiceManager();\n";
@@ -212,7 +264,7 @@
out.sIf("baseInterface != nullptr", [&]() {
out << "iface = new " << fqName.getInterfacePassthroughName()
<< "(" << interfaceName << "::castFrom(baseInterface));\n";
- });
+ }).endl();
}).endl();
}).endl();
}).endl();
diff --git a/utils/Formatter.cpp b/utils/Formatter.cpp
index db763d9..503d145 100644
--- a/utils/Formatter.cpp
+++ b/utils/Formatter.cpp
@@ -86,6 +86,11 @@
return this->block(block);
}
+Formatter &Formatter::sFor(const std::string &stmts, std::function<void(void)> block) {
+ (*this) << "for (" << stmts << ") ";
+ return this->block(block);
+}
+
Formatter &Formatter::sTry(std::function<void(void)> block) {
(*this) << "try ";
return this->block(block);
@@ -101,6 +106,11 @@
return this->block(block);
}
+Formatter &Formatter::sWhile(const std::string &cond, std::function<void(void)> block) {
+ (*this) << "while (" << cond << ") ";
+ return this->block(block);
+}
+
Formatter &Formatter::operator<<(const std::string &out) {
const size_t len = out.length();
size_t start = 0;
diff --git a/utils/include/hidl-util/Formatter.h b/utils/include/hidl-util/Formatter.h
index 7e0c4f9..57fb3b6 100644
--- a/utils/include/hidl-util/Formatter.h
+++ b/utils/include/hidl-util/Formatter.h
@@ -79,6 +79,11 @@
Formatter &sElseIf(const std::string &cond, std::function<void(void)> block);
Formatter &sElse(std::function<void(void)> block);
+ // out.sFor("int i = 0; i < 10; i++", [&] {
+ // out << "printf(\"%d\", i);\n";
+ // }).endl();
+ Formatter &sFor(const std::string &stmts, std::function<void(void)> block);
+
// out.sTry([&] {
// out << "throw RemoteException();\n"
// }).sCatch("RemoteException ex", [&] {
@@ -91,6 +96,11 @@
Formatter &sCatch(const std::string &exception, std::function<void(void)> block);
Formatter &sFinally(std::function<void(void)> block);
+ // out.sWhile("z < 10", [&] {
+ // out << "z++;\n";
+ // }).endl();
+ Formatter &sWhile(const std::string &cond, std::function<void(void)> block);
+
Formatter &operator<<(const std::string &out);
Formatter &operator<<(size_t n);