import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

netwerk/cache/nsDiskCache.h

@@ -0,0 +1,72 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#ifndef _nsDiskCache_h_
+#define _nsDiskCache_h_
+
+#include "nsCacheEntry.h"
+
+#ifdef XP_WIN
+#include <winsock.h>  // for htonl/ntohl
+#endif
+
+
+class nsDiskCache {
+public:
+    enum {
+            kCurrentVersion = 0x00010013      // format = 16 bits major version/16 bits minor version
+    };
+
+    enum { kData, kMetaData };
+
+    // Stores the reason why the cache is corrupt.
+    // Note: I'm only listing the enum values explicitly for easy mapping when
+    // looking at telemetry data.
+    enum CorruptCacheInfo {
+      kNotCorrupt = 0,
+      kInvalidArgPointer = 1,
+      kUnexpectedError = 2,
+      kOpenCacheMapError = 3,
+      kBlockFilesShouldNotExist = 4,
+      kOutOfMemory = 5,
+      kCreateCacheSubdirectories = 6,
+      kBlockFilesShouldExist = 7,
+      kHeaderSizeNotRead = 8,
+      kHeaderIsDirty = 9,
+      kVersionMismatch = 10,
+      kRecordsIncomplete = 11,
+      kHeaderIncomplete = 12,
+      kNotEnoughToRead = 13,
+      kEntryCountIncorrect = 14,
+      kCouldNotGetBlockFileForIndex = 15,
+      kCouldNotCreateBlockFile = 16,
+      kBlockFileSizeError = 17,
+      kBlockFileBitMapWriteError = 18,
+      kBlockFileSizeLessThanBitMap = 19,
+      kBlockFileBitMapReadError = 20,
+      kBlockFileEstimatedSizeError = 21,
+      kFlushHeaderError = 22,
+      kCacheCleanFilePathError = 23,
+      kCacheCleanOpenFileError = 24,
+      kCacheCleanTimerError = 25
+    };
+
+    // Parameter initval initializes internal state of hash function. Hash values are different
+    // for the same text when different initval is used. It can be any random number.
+    // 
+    // It can be used for generating 64-bit hash value:
+    //   (uint64_t(Hash(key, initval1)) << 32) | Hash(key, initval2)
+    //
+    // It can be also used to hash multiple strings:
+    //   h = Hash(string1, 0);
+    //   h = Hash(string2, h);
+    //   ... 
+    static PLDHashNumber    Hash(const char* key, PLDHashNumber initval=0);
+    static nsresult         Truncate(PRFileDesc *  fd, uint32_t  newEOF);
+};
+
+#endif // _nsDiskCache_h_