Share link header parsing code between blink and content.

net/http/http_util.h

Index: net/http/http_util.h
diff --git a/net/http/http_util.h b/net/http/http_util.h
index 458a7187441a253e2ad862785fb076824f1643c6..e1b68b999920fdd3b27db6b51cbea8d37cdab8a0 100644
--- a/net/http/http_util.h
+++ b/net/http/http_util.h
@@ -134,6 +134,17 @@ class NET_EXPORT HttpUtil {
   // Same as above.
   static std::string Unquote(const std::string& str);
 
+  // Similar to Unquote(), but additionally validates that the string being
+  // unescaped actually is a valid quoted string. Returns false for an empty
+  // string, a string without quotes, a string with mismatched quotes, and
+  // a string with unescaped embeded quotes.
+  static bool StrictUnquote(std::string::const_iterator begin,
+                            std::string::const_iterator end,
+                            std::string* out);
+
+  // Same as above.
+  static bool StrictUnquote(const std::string& str, std::string* out);
+
   // The reverse of Unquote() -- escapes and surrounds with "
   static std::string Quote(const std::string& str);
 
@@ -338,10 +349,17 @@ class NET_EXPORT HttpUtil {
     // corresponding equals sign.
     enum OptionalValues { VALUES_OPTIONAL, VALUES_NOT_OPTIONAL };
 
+    // Whether or not unmatched quotes should be considered a failure. By
+    // default this class is pretty lenient and does a best effort to parse
+    // values with mismatched quotes. When set to STRICT_QUOTES a value with
+    // mismatched or otherwise invalid quotes is considered a parse error.
+    enum StrictQuotes { STRICT_QUOTES, NON_STRICT_QUOTES };
+
     NameValuePairsIterator(std::string::const_iterator begin,
                            std::string::const_iterator end,
                            char delimiter,
-                           OptionalValues optional_values);
+                           OptionalValues optional_values,
+                           StrictQuotes strict_quotes = NON_STRICT_QUOTES);
 
     // Treats values as not optional by default (VALUES_NOT_OPTIONAL).
     NameValuePairsIterator(std::string::const_iterator begin,
@@ -403,6 +421,8 @@ class NET_EXPORT HttpUtil {
     // True if values are required for each name/value pair; false if a
     // name is permitted to appear without a corresponding value.
     bool values_optional_;
+
+    bool strict_quotes_;
   };
 };