Fix the case where the browser livelocks if we cannot open a file.

net/base/upload_data.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_BASE_UPLOAD_DATA_H_
 #define NET_BASE_UPLOAD_DATA_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/file_path.h"
+#include "base/platform_file.h"
 #include "base/ref_counted.h"
 #include "testing/gtest/include/gtest/gtest_prod.h"
 
 namespace net {
 
 class UploadData : public base::RefCounted<UploadData> {
  public:
   UploadData() : identifier_(0) {}
 
   enum Type {
     TYPE_BYTES,
     TYPE_FILE
   };
 
   class Element {
    public:
     Element() : type_(TYPE_BYTES), file_range_offset_(0),
-                file_range_length_(kuint64max),
+                file_range_length_(0),
+                file_(base::kInvalidPlatformFileValue),
                 override_content_length_(false) {
     }
 
     Type type() const { return type_; }
     const std::vector<char>& bytes() const { return bytes_; }
     const FilePath& file_path() const { return file_path_; }
     uint64 file_range_offset() const { return file_range_offset_; }
     uint64 file_range_length() const { return file_range_length_; }
 
     void SetToBytes(const char* bytes, int bytes_len) {
       type_ = TYPE_BYTES;
       bytes_.assign(bytes, bytes + bytes_len);
     }
 
     void SetToFilePath(const FilePath& path) {
       SetToFilePathRange(path, 0, kuint64max);
     }
 
-    void SetToFilePathRange(const FilePath& path,
-                            uint64 offset, uint64 length) {
-      type_ = TYPE_FILE;
-      file_path_ = path;
-      file_range_offset_ = offset;
-      file_range_length_ = length;
-    }
+    void SetToFilePathRange(const FilePath& path, uint64 offset, uint64 length);
 
     // Returns the byte-length of the element.  For files that do not exist, 0
     // is returned.  This is done for consistency with Mozilla.
-    uint64 GetContentLength() const;
+    uint64 GetContentLength() const {
+      if (override_content_length_)
+        return content_length_;
+
+      if (type_ == TYPE_BYTES) {
+        return bytes_.size();
+      } else {
+        return file_range_length_;
+      }
+    }
+
+    // For a TYPE_FILE, return a handle to the file. The caller does not take
+    // ownership and should not close the file handle.
+    base::PlatformFile platform_file() const;
+
+    // For a TYPE_FILE, this closes the file handle. It's a fatal error to call
+    // platform_file() after this.
+    void Close();
 
    private:
+    // type_ == TYPE_BYTES:
+    //   bytes_ is valid
+    // type_ == TYPE_FILE:
+    //   file_path_ should always be valid.
+    //
+    //   platform_file() may be invalid, in which case file_range_* are 0 and
+    //   file_ is invalid. This occurs when we cannot open the requested file.
+    //
+    //   Else, then file_range_* are within range of the length of the file
+    //   that we found when opening the file. Also, the sum of offset and
+    //   length will not overflow a uint64. file_ will be handle to the file.
+
     // Allows tests to override the result of GetContentLength.
     void SetContentLength(uint64 content_length) {
       override_content_length_ = true;
       content_length_ = content_length;
     }
 
     Type type_;
     std::vector<char> bytes_;
     FilePath file_path_;
     uint64 file_range_offset_;
     uint64 file_range_length_;
+    base::PlatformFile file_;
     bool override_content_length_;
     uint64 content_length_;
 
     FRIEND_TEST(UploadDataStreamTest, FileSmallerThanLength);
     FRIEND_TEST(HttpNetworkTransactionTest, UploadFileSmallerThanLength);
   };
 
   void AppendBytes(const char* bytes, int bytes_len) {
     if (bytes_len > 0) {
       elements_.push_back(Element());
@@ skipping 20 matching lines @@
   }
 
   void set_elements(const std::vector<Element>& elements) {
     elements_ = elements;
   }
 
   void swap_elements(std::vector<Element>* elements) {
     elements_.swap(*elements);
   }
 
+  // CloseFiles closes the file handles of all Elements of type TYPE_FILE.
+  void CloseFiles();
+
   // Identifies a particular upload instance, which is used by the cache to
   // formulate a cache key.  This value should be unique across browser
   // sessions.  A value of 0 is used to indicate an unspecified identifier.
   void set_identifier(int64 id) { identifier_ = id; }
   int64 identifier() const { return identifier_; }
 
  private:
   friend class base::RefCounted<UploadData>;
 
   ~UploadData() {}
 
   std::vector<Element> elements_;
   int64 identifier_;
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_UPLOAD_DATA_H_