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..34e82fe853a1aeb3026e0ea2080e7cffeb9a2d5e 100644
--- a/net/http/http_util.h
+++ b/net/http/http_util.h
@@ -134,6 +134,18 @@ 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

[mmenke, 2016/04/26 18:05:58]

Think we should mention this still allows single quotes, contrary to RFC 2616.

[Marijn Kruisselbrink, 2016/04/27 01:49:49]

Done

+  // 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) WARN_UNUSED_RESULT;

[mmenke, 2016/04/26 18:05:58]

nit:  Include "base/macros.h" for WARN_UNUSED_RESULT.

[Marijn Kruisselbrink, 2016/04/27 01:49:49]

Done

+
+  // Same as above.
+  static bool StrictUnquote(const std::string& str,
+                            std::string* out) WARN_UNUSED_RESULT;
+
   // The reverse of Unquote() -- escapes and surrounds with "
   static std::string Quote(const std::string& str);
 
@@ -332,18 +344,26 @@ class NET_EXPORT HttpUtil {
   // calls to GetNext() or after the NameValuePairsIterator is destroyed.
   class NET_EXPORT NameValuePairsIterator {
    public:
-    // Whether or not values are optional. VALUES_OPTIONAL allows
-    // e.g. name1=value1;name2;name3=value3, whereas VALUES_NOT_OPTIONAL
+    // Whether or not values are optional. Values::OPTIONAL allows
+    // e.g. name1=value1;name2;name3=value3, whereas Vaues::NOT_OPTIONAL
     // will treat it as a parse error because name2 does not have a
     // corresponding equals sign.
-    enum OptionalValues { VALUES_OPTIONAL, VALUES_NOT_OPTIONAL };
+    enum class Values { OPTIONAL, 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 a value with
+    // mismatched or otherwise invalid quotes is considered a parse error.
+    enum class Quotes { STRICT, NOT_STRICT };
 
     NameValuePairsIterator(std::string::const_iterator begin,
                            std::string::const_iterator end,
                            char delimiter,
-                           OptionalValues optional_values);
+                           Values optional_values,
+                           Quotes strict_quotes);
 
-    // Treats values as not optional by default (VALUES_NOT_OPTIONAL).
+    // Treats values as not optional by default (Values::NOT_OPTIONAL) and
+    // treats quotes as not strict.
     NameValuePairsIterator(std::string::const_iterator begin,
                            std::string::const_iterator end,
                            char delimiter);
@@ -403,6 +423,11 @@ 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_;
+
+    // True if quotes values are required to be properly quoted; false if
+    // mismatched quotes and other problems with quoted values should be more
+    // or less gracefully treated as valid.
+    bool strict_quotes_;
   };
 };