dom/cache/FileUtils.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_cache_FileUtils_h
   8 #define mozilla_dom_cache_FileUtils_h
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/dom/cache/Types.h"
  12 #include "CacheCommon.h"
  13 #include "mozIStorageConnection.h"
  14 #include "nsStreamUtils.h"
  15 #include "nsTArrayForwardDeclare.h"
  16
  17 struct nsID;
  18 class nsIFile;
  19
  20 namespace mozilla::dom::cache {
  21
  22 #define PADDING_FILE_NAME u".padding"
  23 #define PADDING_TMP_FILE_NAME u".padding-tmp"
  24
  25 enum class DirPaddingFile { FILE, TMP_FILE };
  26
  27 nsresult BodyCreateDir(nsIFile& aBaseDir);
  28
  29 // Note that this function can only be used during the initialization of the
  30 // database.  We're unlikely to be able to delete the DB successfully past
  31 // that point due to the file being in use.
  32 nsresult BodyDeleteDir(const CacheDirectoryMetadata& aDirectoryMetadata,
  33                        nsIFile& aBaseDir);
  34
  35 // Returns a Result with a success value with the body id and, optionally, the
  36 // copy context.
  37 Result<std::pair<nsID, nsCOMPtr<nsISupports>>, nsresult> BodyStartWriteStream(
  38     const CacheDirectoryMetadata& aDirectoryMetadata, nsIFile& aBaseDir,
  39     nsIInputStream& aSource, void* aClosure, nsAsyncCopyCallbackFun aCallback);
  40
  41 void BodyCancelWrite(nsISupports& aCopyContext);
  42
  43 nsresult BodyFinalizeWrite(nsIFile& aBaseDir, const nsID& aId);
  44
  45 Result<MovingNotNull<nsCOMPtr<nsIInputStream>>, nsresult> BodyOpen(
  46     const CacheDirectoryMetadata& aDirectoryMetadata, nsIFile& aBaseDir,
  47     const nsID& aId);
  48
  49 nsresult BodyMaybeUpdatePaddingSize(
  50     const CacheDirectoryMetadata& aDirectoryMetadata, nsIFile& aBaseDir,
  51     const nsID& aId, uint32_t aPaddingInfo, int64_t* aPaddingSizeInOut);
  52
  53 nsresult BodyDeleteFiles(const CacheDirectoryMetadata& aDirectoryMetadata,
  54                          nsIFile& aBaseDir, const nsTArray<nsID>& aIdList);
  55
  56 nsresult BodyDeleteOrphanedFiles(
  57     const CacheDirectoryMetadata& aDirectoryMetadata, nsIFile& aBaseDir,
  58     const nsTArray<nsID>& aKnownBodyIdList);
  59
  60 // If aCanRemoveFiles is true, that means we are safe to touch the files which
  61 // can be accessed in other threads.
  62 // If it's not, that means we cannot remove the files which are possible to
  63 // created by other threads. Note that if the files are not expected, we should
  64 // be safe to remove them in any case.
  65 template <typename Func>
  66 nsresult BodyTraverseFiles(
  67     const Maybe<CacheDirectoryMetadata>& aDirectoryMetadata, nsIFile& aBodyDir,
  68     const Func& aHandleFileFunc, bool aCanRemoveFiles, bool aTrackQuota = true);
  69
  70 // XXX Remove this method when all callers properly wrap aClientMetadata with
  71 // Some/Nothing
  72 template <typename Func>
  73 nsresult BodyTraverseFiles(const CacheDirectoryMetadata& aDirectoryMetadata,
  74                            nsIFile& aBodyDir, const Func& aHandleFileFunc,
  75                            bool aCanRemoveFiles, bool aTrackQuota = true) {
  76   return BodyTraverseFiles(Some(aDirectoryMetadata), aBodyDir, aHandleFileFunc,
  77                            aCanRemoveFiles, aTrackQuota);
  78 }
  79
  80 nsresult CreateMarkerFile(const CacheDirectoryMetadata& aDirectoryMetadata);
  81
  82 nsresult DeleteMarkerFile(const CacheDirectoryMetadata& aDirectoryMetadata);
  83
  84 bool MarkerFileExists(const CacheDirectoryMetadata& aDirectoryMetadata);
  85
  86 nsresult RemoveNsIFileRecursively(
  87     const Maybe<CacheDirectoryMetadata>& aDirectoryMetadata, nsIFile& aFile,
  88     bool aTrackQuota = true);
  89
  90 // XXX Remove this method when all callers properly wrap aClientMetadata with
  91 // Some/Nothing
  92 inline nsresult RemoveNsIFileRecursively(
  93     const CacheDirectoryMetadata& aDirectoryMetadata, nsIFile& aFile,
  94     bool aTrackQuota = true) {
  95   return RemoveNsIFileRecursively(Some(aDirectoryMetadata), aFile, aTrackQuota);
  96 }
  97
  98 // Delete a file that you think exists. If the file doesn't exist, an error
  99 // will not be returned, but warning telemetry will be generated! So only call
 100 // this on files that you know exist (idempotent usage, but it's not
 101 // recommended).
 102 nsresult RemoveNsIFile(const Maybe<CacheDirectoryMetadata>& aDirectoryMetadata,
 103                        nsIFile& aFile, bool aTrackQuota = true);
 104
 105 // XXX Remove this method when all callers properly wrap aClientMetadata with
 106 // Some/Nothing
 107 inline nsresult RemoveNsIFile(const CacheDirectoryMetadata& aDirectoryMetadata,
 108                               nsIFile& aFile, bool aTrackQuota = true) {
 109   return RemoveNsIFile(Some(aDirectoryMetadata), aFile, aTrackQuota);
 110 }
 111
 112 void DecreaseUsageForDirectoryMetadata(
 113     const CacheDirectoryMetadata& aDirectoryMetadata, int64_t aUpdatingSize);
 114
 115 /**
 116  * This function is used to check if the directory padding file is existed.
 117  */
 118 bool DirectoryPaddingFileExists(nsIFile& aBaseDir,
 119                                 DirPaddingFile aPaddingFileType);
 120
 121 /**
 122  *
 123  * The functions below are used to read/write/delete the directory padding file
 124  * after acquiring the mutex lock. The mutex lock is held by
 125  * CacheQuotaClient to prevent multi-thread accessing issue. To avoid deadlock,
 126  * these functions should only access by static functions in
 127  * dom/cache/QuotaClient.cpp.
 128  *
 129  */
 130
 131 // Returns a Result with a success value denoting the padding size.
 132 Result<int64_t, nsresult> DirectoryPaddingGet(nsIFile& aBaseDir);
 133
 134 nsresult DirectoryPaddingInit(nsIFile& aBaseDir);
 135
 136 nsresult UpdateDirectoryPaddingFile(nsIFile& aBaseDir,
 137                                     mozIStorageConnection& aConn,
 138                                     int64_t aIncreaseSize,
 139                                     int64_t aDecreaseSize,
 140                                     bool aTemporaryFileExist);
 141
 142 nsresult DirectoryPaddingFinalizeWrite(nsIFile& aBaseDir);
 143
 144 // Returns a Result with a success value denoting the padding size.
 145 Result<int64_t, nsresult> DirectoryPaddingRestore(nsIFile& aBaseDir,
 146                                                   mozIStorageConnection& aConn,
 147                                                   bool aMustRestore);
 148
 149 nsresult DirectoryPaddingDeleteFile(nsIFile& aBaseDir,
 150                                     DirPaddingFile aPaddingFileType);
 151 }  // namespace mozilla::dom::cache
 152
 153 #endif  // mozilla_dom_cache_FileUtils_h