Snap for 7243396 from ee47ab21d540f11f6b5ff8abec8872b212429bf7 to sc-release am: 6e0d6b100b

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/libhidl/+/14022895

Change-Id: Ia410fe7e6335a2917d15fe9e74fa70ee43410765

3 files changed, 26 insertions, 1 deletions

diff --git a/base/HidlSupport.cpp b/base/HidlSupport.cpp
index af805b9..78faa2f 100644
--- a/base/HidlSupport.cpp
+++ b/base/HidlSupport.cpp
@@ -217,6 +217,14 @@ void hidl_string::copyFrom(const char *data, size_t size) {
     if (size >= UINT32_MAX) {
         LOG(FATAL) << "string size can't exceed 2^32 bytes: " << size;
     }
+
+    if (size == 0) {
+        mBuffer = kEmptyString;
+        mSize = 0;
+        mOwnsBuffer = false;
+        return;
+    }
+
     char *buf = (char *)malloc(size + 1);
     memcpy(buf, data, size);
     buf[size] = '\0';
diff --git a/test_main.cpp b/test_main.cpp
index ea4dfd1..5c6c78e 100644
--- a/test_main.cpp
+++ b/test_main.cpp
@@ -175,6 +175,20 @@ TEST_F(LibHidlTest, StringTest) {
     EXPECT_FALSE(hs2 <= hs1);
 }
 
+// empty string optimization should apply for any constructor
+TEST_F(LibHidlTest, HidlStringEmptyLiteralAllocation) {
+    using android::hardware::hidl_string;
+
+    hidl_string empty1;
+    hidl_string empty2("");
+    hidl_string empty3("foo", 0);
+    hidl_string empty4((std::string()));
+
+    EXPECT_EQ(empty1.c_str(), empty2.c_str());
+    EXPECT_EQ(empty1.c_str(), empty3.c_str());
+    EXPECT_EQ(empty1.c_str(), empty4.c_str());
+}
+
 TEST_F(LibHidlTest, MemoryTest) {
     using android::hardware::hidl_memory;
 
diff --git a/transport/include/hidl/ServiceManagement.h b/transport/include/hidl/ServiceManagement.h
index c8e8f6c..886e816 100644
--- a/transport/include/hidl/ServiceManagement.h
+++ b/transport/include/hidl/ServiceManagement.h
@@ -54,7 +54,10 @@ void setTrebleTestingOverride(bool testingOverride);
 void preloadPassthroughService(const std::string &descriptor);
 
 // Returns a service with the following constraints:
-// - retry => service is waited for and returned if available in this process
+// - retry => service is waited for and returned if it is declared in the
+//     manifest AND it is available in this process (if errors indicate an
+//     sepolicy denial, then this will return - TODO(b/28321379) more precise
+//     errors to handle more cases)
 // - getStub => internal only. Forces to get the unwrapped (no BsFoo) if available.
 // TODO(b/65843592)
 // If the service is a remote service, this function returns BpBase. If the service is