Append to output instead of overwriting it in http2::HuffmanEncode().
No functional change.
PiperOrigin-RevId: 336085818
Change-Id: I84b8474b06df799cb6ae43d8a4f90a3b51c37e92
diff --git a/http2/hpack/huffman/hpack_huffman_encoder.cc b/http2/hpack/huffman/hpack_huffman_encoder.cc
index a5eeaf9..ce6009a 100644
--- a/http2/hpack/huffman/hpack_huffman_encoder.cc
+++ b/http2/hpack/huffman/hpack_huffman_encoder.cc
@@ -21,8 +21,7 @@
size_t encoded_size,
std::string* huffman) {
DCHECK(huffman != nullptr);
- huffman->clear(); // Note that this doesn't release memory.
- huffman->reserve(encoded_size);
+ huffman->reserve(huffman->size() + encoded_size);
uint64_t bit_buffer = 0; // High-bit is next bit to output. Not clear if that
// is more performant than having the low-bit be the
// last to be output.
diff --git a/http2/hpack/huffman/hpack_huffman_encoder.h b/http2/hpack/huffman/hpack_huffman_encoder.h
index a6597db..c3ac1f6 100644
--- a/http2/hpack/huffman/hpack_huffman_encoder.h
+++ b/http2/hpack/huffman/hpack_huffman_encoder.h
@@ -22,9 +22,8 @@
// Encode the plain text string |plain| with the Huffman encoding defined in the
// HPACK RFC, 7541. |encoded_size| is used to pre-allocate storage and it
-// should be the value returned by HuffmanSize(). |*huffman| does not have to
-// be empty, it is cleared at the beginning of this function. This allows
-// reusing the same string object across multiple invocations.
+// should be the value returned by HuffmanSize(). Appends the result to
+// |*huffman|.
QUICHE_EXPORT_PRIVATE void HuffmanEncode(quiche::QuicheStringPiece plain,
size_t encoded_size,
std::string* huffman);
diff --git a/http2/hpack/huffman/hpack_huffman_encoder_test.cc b/http2/hpack/huffman/hpack_huffman_encoder_test.cc
index a5ad105..9e7f7bb 100644
--- a/http2/hpack/huffman/hpack_huffman_encoder_test.cc
+++ b/http2/hpack/huffman/hpack_huffman_encoder_test.cc
@@ -115,6 +115,7 @@
}
}
+// Test that encoding appends to output without overwriting it.
TEST_P(HuffmanEncoderTest, AppendToOutput) {
size_t encoded_size = HuffmanSize("foo");
std::string buffer;
@@ -123,14 +124,7 @@
encoded_size = HuffmanSize("bar");
Encode("bar", encoded_size, &buffer);
-
- if (use_fast_encoder_) {
- // HuffmanEncodeFast() appends to output allowing callers to eliminate copy.
- EXPECT_EQ(Http2HexDecode("94e78c767f"), buffer);
- } else {
- // HuffmanEncode() clears output before encoding.
- EXPECT_EQ(Http2HexDecode("8c767f"), buffer);
- }
+ EXPECT_EQ(Http2HexDecode("94e78c767f"), buffer);
}
} // namespace
diff --git a/quic/core/qpack/qpack_instruction_encoder.cc b/quic/core/qpack/qpack_instruction_encoder.cc
index 6a15db8..e7f5f4f 100644
--- a/quic/core/qpack/qpack_instruction_encoder.cc
+++ b/quic/core/qpack/qpack_instruction_encoder.cc
@@ -141,6 +141,7 @@
DCHECK_EQ(0, byte_ & (1 << field_->param));
byte_ |= (1 << field_->param);
+ huffman_encoded_string_.clear();
http2::HuffmanEncode(string_to_write_, encoded_size,
&huffman_encoded_string_);
string_to_write_ = huffman_encoded_string_;
