Changed the semantics of Buffer::Clear to not alter the capacity
Also added a test for Clear to ensure this invariant holds.
With this change, it is easy to empty a Buffer and reuse its storage. Further down the line, code filling data into a Buffer could be written to just append to it, with the caller determining if the Buffer should first be cleared or not.
There is currently only one use of Buffer::Clear (in AudioEncoderCopyRed::Reset()) and it should benefit from the change, by not requiring a reallocation after Reset.
Review URL: https://codereview.webrtc.org/1707693002
Cr-Commit-Position: refs/heads/master@{#11680}
diff --git a/webrtc/base/buffer.h b/webrtc/base/buffer.h
index 5c9380a..2340396 100644
--- a/webrtc/base/buffer.h
+++ b/webrtc/base/buffer.h
@@ -180,12 +180,10 @@
return std::move(*this);
}
- // Resets the buffer to zero size and capacity. Works even if the buffer has
- // been moved from.
+ // Resets the buffer to zero size without altering capacity. Works even if the
+ // buffer has been moved from.
void Clear() {
- data_.reset();
size_ = 0;
- capacity_ = 0;
assert(IsConsistent());
}
diff --git a/webrtc/base/buffer_unittest.cc b/webrtc/base/buffer_unittest.cc
index 0b93b9b..f917bc6 100644
--- a/webrtc/base/buffer_unittest.cc
+++ b/webrtc/base/buffer_unittest.cc
@@ -177,4 +177,16 @@
EXPECT_EQ(buf2.data(), data1);
}
+TEST(BufferTest, TestClear) {
+ Buffer buf;
+ buf.SetData(kTestData, 15);
+ EXPECT_EQ(buf.size(), 15u);
+ EXPECT_EQ(buf.capacity(), 15u);
+ const char *data = buf.data<char>();
+ buf.Clear();
+ EXPECT_EQ(buf.size(), 0u);
+ EXPECT_EQ(buf.capacity(), 15u); // Hasn't shrunk.
+ EXPECT_EQ(buf.data<char>(), data); // No reallocation.
+}
+
} // namespace rtc
