[master] libbinder: writeInterfaceToken char16_t* variant

This avoids the extra allocation when we don't already have a String16
created (specifically for Java).

Bug: 169674485
Test: atest aidl_integration_test
Change-Id: I3a6344bfdc8010f07812d7d8efbbdfd2a32c7a5e

2 files changed, 7 insertions, 1 deletions

diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index 64a4f9bf6d..5a802a92a4 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -528,14 +528,19 @@ constexpr int32_t kHeader = B_PACK_CHARS('S', 'Y', 'S', 'T');
 // Write RPC headers.  (previously just the interface token)
 status_t Parcel::writeInterfaceToken(const String16& interface)
 {
+    return writeInterfaceToken(interface.string(), interface.size());
+}
+
+status_t Parcel::writeInterfaceToken(const char16_t* str, size_t len) {
     const IPCThreadState* threadState = IPCThreadState::self();
     writeInt32(threadState->getStrictModePolicy() | STRICT_MODE_PENALTY_GATHER);
     updateWorkSourceRequestHeaderPosition();
     writeInt32(threadState->shouldPropagateWorkSource() ?
             threadState->getCallingWorkSourceUid() : IPCThreadState::kUnsetWorkSource);
     writeInt32(kHeader);
+
     // currently the interface identification token is just its name as a string
-    return writeString16(interface);
+    return writeString16(str, len);
 }
 
 bool Parcel::replaceCallingWorkSourceUid(uid_t uid)
diff --git a/libs/binder/include/binder/Parcel.h b/libs/binder/include/binder/Parcel.h
index c1f64fb541..cca057c104 100644
--- a/libs/binder/include/binder/Parcel.h
+++ b/libs/binder/include/binder/Parcel.h
@@ -86,6 +86,7 @@ public:
 
     // Writes the RPC header.
     status_t            writeInterfaceToken(const String16& interface);
+    status_t            writeInterfaceToken(const char16_t* str, size_t len);
 
     // Parses the RPC header, returning true if the interface name
     // in the header matches the expected interface from the caller.