Introduce ResourceResponse::AddHttpHeaderFieldWithMultipleValues

To avoid inefficient AtomicString concatting when the header value has
multiple commas.

Bug: 930150
Change-Id: I33439d188be20d130278a961ec6ad82d2ba7fa7b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1893608Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Tsuyoshi Horo <horo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#712480}

third_party/blink/renderer/platform/loader/fetch/resource_response.cc

@@ -40,6 +40,7 @@
 #include "third_party/blink/renderer/platform/network/http_parsers.h"
 #include "third_party/blink/renderer/platform/wtf/assertions.h"
 #include "third_party/blink/renderer/platform/wtf/std_lib_extras.h"
+#include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
 
 namespace blink {
 
@@ -263,6 +264,26 @@ void ResourceResponse::AddHttpHeaderField(const AtomicString& name,
     result.stored_value->value = result.stored_value->value + ", " + value;
 }
 
+void ResourceResponse::AddHttpHeaderFieldWithMultipleValues(
+    const AtomicString& name,
+    const Vector<AtomicString>& values) {
+  if (values.IsEmpty())
+    return;
+
+  UpdateHeaderParsedState(name);
+
+  StringBuilder value_builder;
+  const auto it = http_header_fields_.Find(name);
+  if (it != http_header_fields_.end())
+    value_builder.Append(it->value);
+  for (const auto& value : values) {
+    if (!value_builder.IsEmpty())
+      value_builder.Append(", ");
+    value_builder.Append(value);
+  }
+  http_header_fields_.Set(name, value_builder.ToAtomicString());
+}
+
 void ResourceResponse::ClearHttpHeaderField(const AtomicString& name) {
   http_header_fields_.Remove(name);
 }

third_party/blink/renderer/platform/loader/fetch/resource_response.h

@@ -223,6 +223,8 @@ class PLATFORM_EXPORT ResourceResponse final {
   const AtomicString& HttpHeaderField(const AtomicString& name) const;
   void SetHttpHeaderField(const AtomicString& name, const AtomicString& value);
   void AddHttpHeaderField(const AtomicString& name, const AtomicString& value);
+  void AddHttpHeaderFieldWithMultipleValues(const AtomicString& name,
+                                            const Vector<AtomicString>& values);
   void ClearHttpHeaderField(const AtomicString& name);
   const HTTPHeaderMap& HttpHeaderFields() const;
 

third_party/blink/renderer/platform/loader/fetch/resource_response_test.cc

@@ -84,4 +84,22 @@ TEST(ResourceResponseTest, CrossThreadAtomicStrings) {
   thread.reset();
 }
 
+TEST(ResourceResponseTest, AddHttpHeaderFieldWithMultipleValues) {
+  ResourceResponse response(CreateTestResponse());
+
+  Vector<AtomicString> empty_values;
+  response.AddHttpHeaderFieldWithMultipleValues("set-cookie", empty_values);
+  EXPECT_EQ(AtomicString(), response.HttpHeaderField("set-cookie"));
+
+  response.AddHttpHeaderField("set-cookie", "a=1");
+  EXPECT_EQ("a=1", response.HttpHeaderField("set-cookie"));
+
+  Vector<AtomicString> values;
+  values.push_back("b=2");
+  values.push_back("c=3");
+  response.AddHttpHeaderFieldWithMultipleValues("set-cookie", values);
+
+  EXPECT_EQ("a=1, b=2, c=3", response.HttpHeaderField("set-cookie"));
+}
+
 }  // namespace blink

third_party/blink/renderer/platform/network/http_parsers.cc

@@ -42,6 +42,7 @@
 #include "third_party/blink/renderer/platform/network/http_names.h"
 #include "third_party/blink/renderer/platform/wtf/date_math.h"
 #include "third_party/blink/renderer/platform/wtf/math_extras.h"
+#include "third_party/blink/renderer/platform/wtf/text/atomic_string.h"
 #include "third_party/blink/renderer/platform/wtf/text/character_names.h"
 #include "third_party/blink/renderer/platform/wtf/text/parsing_utilities.h"
 #include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
@@ -497,10 +498,13 @@ bool ParseMultipartHeadersFromBody(const char* bytes,
     size_t iterator = 0;
 
     response->ClearHttpHeaderField(header);
+    Vector<AtomicString> values;
     while (response_headers->EnumerateHeader(&iterator, header_string_piece,
                                              &value)) {
-      response->AddHttpHeaderField(header, WebString::FromLatin1(value));
+      const AtomicString atomic_value = WebString::FromLatin1(value);
+      values.push_back(atomic_value);
     }
+    response->AddHttpHeaderFieldWithMultipleValues(header, values);
   }
   return true;
 }

third_party/blink/renderer/platform/network/http_parsers_test.cc

@@ -320,8 +320,14 @@ TEST(HTTPParsersTest, ParseMultipartHeaders) {
   response.AddHttpHeaderField("foo", "bar");
   response.AddHttpHeaderField("range", "piyo");
   response.AddHttpHeaderField("content-length", "999");
-
-  const char kData[] = "content-type: image/png\ncontent-length: 10\n\n";
+  response.AddHttpHeaderField("set-cookie", "a=1");
+
+  const char kData[] =
+      "content-type: image/png\n"
+      "content-length: 10\n"
+      "set-cookie: x=2\n"
+      "set-cookie: y=3\n"
+      "\n";
   wtf_size_t end = 0;
   bool result =
       ParseMultipartHeadersFromBody(kData, strlen(kData), &response, &end);
@@ -332,6 +338,7 @@ TEST(HTTPParsersTest, ParseMultipartHeaders) {
   EXPECT_EQ("10", response.HttpHeaderField("content-length"));
   EXPECT_EQ("bar", response.HttpHeaderField("foo"));
   EXPECT_EQ(AtomicString(), response.HttpHeaderField("range"));
+  EXPECT_EQ("x=2, y=3", response.HttpHeaderField("set-cookie"));
 }
 
 TEST(HTTPParsersTest, ParseMultipartHeadersContentCharset) {