commit 5708fb4e117f06f8b867eb623d73fd3e5d969155
author Yifan Hong <elsk@google.com> Wed Oct 26 17:50:29 2016 -0700
committer Yifan Hong <elsk@google.com> Fri Oct 28 18:52:06 2016 -0700
tree 938748cbb9220ba37ba9d3be7e6837f33f3e51f5
parent 5e2318c9d54c3fe9454f2d79bc80ead3782658db

Fix asymmetry in hidl_string::operator==

Bug: 32456816

Test: libhidl-test
Change-Id: If13ef62a18b12cecb466b1e9701da2614ce75db8

include/hidl/HidlSupport.h

diff --git a/include/hidl/HidlSupport.h b/include/hidl/HidlSupport.h
index 07eebeb..37c4431 100644
--- a/include/hidl/HidlSupport.h
+++ b/include/hidl/HidlSupport.h
@@ -76,14 +76,6 @@
     status_t writeEmbeddedToParcel(
             Parcel *parcel, size_t parentHandle, size_t parentOffset) const;
 
-    inline bool operator==(const char *s) const {
-        return strcmp(mBuffer, s) == 0;
-    }
-
-    inline bool operator!=(const char *s) const {
-        return !(operator==(s));
-    }
-
     // offsetof(hidl_string, mBuffer) exposed since mBuffer is private.
     static const size_t kOffsetOfBuffer;
 
@@ -99,6 +91,22 @@
     void moveFrom(hidl_string &&);
 };
 
+inline bool operator==(const hidl_string &hs, const char *s) {
+    return strcmp(hs.c_str(), s) == 0;
+}
+
+inline bool operator!=(const hidl_string &hs, const char *s) {
+    return !(hs == s);
+}
+
+inline bool operator==(const char *s, const hidl_string &hs) {
+    return strcmp(hs.c_str(), s) == 0;
+}
+
+inline bool operator!=(const char *s, const hidl_string &hs) {
+    return !(s == hs);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 template<typename T>

test/main.cpp

diff --git a/test/main.cpp b/test/main.cpp
index fff69b0..f5b5f20 100644
--- a/test/main.cpp
+++ b/test/main.cpp
@@ -105,6 +105,19 @@
     EXPECT_TRUE(flag);
 }
 
+TEST_F(LibHidlTest, StringCmpTest) {
+    using android::hardware::hidl_string;
+    const char * s = "good";
+    hidl_string hs(s);
+    EXPECT_NE(hs.c_str(), s);
+
+    EXPECT_TRUE(hs == s); // operator ==
+    EXPECT_TRUE(s == hs);
+
+    EXPECT_FALSE(hs != s); // operator ==
+    EXPECT_FALSE(s != hs);
+}
+
 template <typename T>
 void great(android::hardware::hidl_vec<T>) {}