Http Cache: Additional byte-range support.

* Now we can serve byte range requests from cached 200s.

* When we receive 304 we make sure that we were expecting it.

* A range request that doesn't fit the currently stored entry
  only deletes the entry if the server confirms that it has
  changed.

* Make sure that LOAD_ONLY_FROM_CACHE causes cache misses for
  byte range requests.

BUG=12258
TEST=unittests

Review URL: http://codereview.chromium.org/165479

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@23601 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 7 insertions, 2 deletions

diff --git a/net/http/partial_data.h b/net/http/partial_data.h
index ade720d..460ff21 100644
--- a/net/http/partial_data.h
+++ b/net/http/partial_data.h
@@ -31,7 +31,8 @@ class IOBuffer;
 // of those individual network / cache requests.
 class PartialData {
  public:
-  PartialData() : range_present_(false), final_range_(false) {}
+  PartialData()
+      : range_present_(false), final_range_(false), sparse_entry_(true) {}
   ~PartialData() {}
 
   // Performs initialization of the object by parsing the request |headers|
@@ -61,10 +62,13 @@ class PartialData {
   bool IsLastRange() const;
 
   // Extracts info from headers already stored in the cache. Returns false if
-  // there is any problem with the headers or the requested range.
+  // there is any problem with the headers.
   bool UpdateFromStoredHeaders(const HttpResponseHeaders* headers,
                                disk_cache::Entry* entry);
 
+  // Returns true if the requested range is valid given the stored data.
+  bool IsRequestedRangeOK();
+
   // Returns true if the response headers match what we expect, false otherwise.
   bool ResponseHeadersOK(const HttpResponseHeaders* headers);
 
@@ -106,6 +110,7 @@ class PartialData {
   std::string extra_headers_;  // The clean set of extra headers (no ranges).
   bool range_present_;  // True if next range entry is already stored.
   bool final_range_;
+  bool sparse_entry_;
 
   DISALLOW_COPY_AND_ASSIGN(PartialData);
 };