dom/system/PathUtils.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_PathUtils__
   8 #define mozilla_dom_PathUtils__
   9
  10 #include "mozilla/DataMutex.h"
  11 #include "mozilla/EnumeratedArray.h"
  12 #include "mozilla/Maybe.h"
  13 #include "mozilla/MozPromise.h"
  14 #include "mozilla/Mutex.h"
  15 #include "mozilla/Result.h"
  16 #include "mozilla/dom/PathUtilsBinding.h"
  17 #include "mozilla/dom/Promise.h"
  18 #include "nsAppDirectoryServiceDefs.h"
  19 #include "nsDirectoryServiceDefs.h"
  20 #include "nsString.h"
  21 #include "nsTArray.h"
  22
  23 namespace mozilla {
  24 class ErrorResult;
  25
  26 namespace dom {
  27
  28 class PathUtils final {
  29  public:
  30   /**
  31    * Initialize the given nsIFile with the given path.
  32    *
  33    * This is equivalent to calling nsIFile::InitWithPath() with the caveat that
  34    * on Windows debug or during Windows CI tests, we will crash if the path
  35    * contains a forward slash.
  36    *
  37    * @param aFile The file to initialize.
  38    * @param aPath The path to initialize the file with.
  39    *
  40    * @return The result of calling nsIFile::InitWithPath.
  41    */
  42   static nsresult InitFileWithPath(nsIFile* aFile, const nsAString& aPath);
  43
  44   static void Filename(const GlobalObject&, const nsAString& aPath,
  45                        nsString& aResult, ErrorResult& aErr);
  46
  47   static void Parent(const GlobalObject&, const nsAString& aPath,
  48                      const int32_t aDepth, nsString& aResult,
  49                      ErrorResult& aErr);
  50
  51   static void Join(const GlobalObject&, const Sequence<nsString>& aComponents,
  52                    nsString& aResult, ErrorResult& aErr);
  53
  54   /**
  55    * Join a sequence of path components and return an nsIFile with the resulting
  56    * path.
  57    *
  58    * @param aComponents  A sequence of path components. The first component must
  59    *                     be an absolute path.
  60    * @param aErr  The error result, if any.
  61    *
  62    * @return An nsIFile with the resulting path, if there were no errors.
  63    * Otherwise, nullptr is returned.
  64    */
  65   static already_AddRefed<nsIFile> Join(const Span<const nsString>& aComponents,
  66                                         ErrorResult& aErr);
  67
  68   static void JoinRelative(const GlobalObject&, const nsAString& aBasePath,
  69                            const nsAString& aRelativePath, nsString& aResult,
  70                            ErrorResult& aErr);
  71
  72   static void ToExtendedWindowsPath(const GlobalObject&, const nsAString& aPath,
  73                                     nsString& aResult, ErrorResult& aErr);
  74
  75   static void Normalize(const GlobalObject&, const nsAString& aPath,
  76                         nsString& aResult, ErrorResult& aErr);
  77
  78   static void Split(const GlobalObject&, const nsAString& aPath,
  79                     nsTArray<nsString>& aResult, ErrorResult& aErr);
  80
  81   static void SplitRelative(const GlobalObject& aGlobal, const nsAString& aPath,
  82                             const SplitRelativeOptions& aOptions,
  83                             nsTArray<nsString>& aResult, ErrorResult& aErr);
  84
  85   static void ToFileURI(const GlobalObject&, const nsAString& aPath,
  86                         nsCString& aResult, ErrorResult& aErr);
  87
  88   static bool IsAbsolute(const GlobalObject&, const nsAString& aPath);
  89
  90   static void GetProfileDirSync(const GlobalObject&, nsString& aResult,
  91                                 ErrorResult& aErr);
  92   static void GetLocalProfileDirSync(const GlobalObject&, nsString& aResult,
  93                                      ErrorResult& aErr);
  94   static void GetTempDirSync(const GlobalObject&, nsString& aResult,
  95                              ErrorResult& aErr);
  96   static void GetXulLibraryPathSync(const GlobalObject&, nsString& aResult,
  97                                     ErrorResult& aErr);
  98
  99   static already_AddRefed<Promise> GetProfileDirAsync(
 100       const GlobalObject& aGlobal, ErrorResult& aErr);
 101   static already_AddRefed<Promise> GetLocalProfileDirAsync(
 102       const GlobalObject& aGlobal, ErrorResult& aErr);
 103   static already_AddRefed<Promise> GetTempDirAsync(const GlobalObject& aGlobal,
 104                                                    ErrorResult& aErr);
 105   static already_AddRefed<Promise> GetXulLibraryPathAsync(
 106       const GlobalObject& aGlobal, ErrorResult& aErr);
 107
 108  private:
 109   class DirectoryCache;
 110   friend class DirectoryCache;
 111
 112   static StaticDataMutex<Maybe<DirectoryCache>> sDirCache;
 113 };
 114
 115 /**
 116  * A cache of commonly used directories
 117  */
 118 class PathUtils::DirectoryCache final {
 119  public:
 120   /**
 121    * A directory that can be requested via |GetDirectorySync| or
 122    * |GetDirectoryAsync|.
 123    */
 124   enum class Directory {
 125     /**
 126      * The user's profile directory.
 127      */
 128     Profile,
 129     /**
 130      * The user's local profile directory.
 131      */
 132     LocalProfile,
 133     /**
 134      * The OS temporary directory.
 135      */
 136     Temp,
 137     /**
 138      * The libxul path.
 139      */
 140     XulLibrary,
 141     /**
 142      * The number of Directory entries.
 143      */
 144     Count,
 145   };
 146
 147   DirectoryCache();
 148   DirectoryCache(const DirectoryCache&) = delete;
 149   DirectoryCache(DirectoryCache&&) = delete;
 150   DirectoryCache& operator=(const DirectoryCache&) = delete;
 151   DirectoryCache& operator=(DirectoryCache&&) = delete;
 152
 153   /**
 154    * Ensure the cache is instantiated and schedule its destructor to run at
 155    * shutdown.
 156    *
 157    * If the cache is already instantiated, this is a no-op.
 158    *
 159    * @param aCache The cache to ensure is instantiated.
 160    */
 161   static DirectoryCache& Ensure(Maybe<DirectoryCache>& aCache);
 162
 163   void GetDirectorySync(nsString& aResult, ErrorResult& aErr,
 164                         const Directory aRequestedDir);
 165
 166   /**
 167    * Request the path of a specific directory.
 168    *
 169    * If the directory has not been requested before, this may require a trip to
 170    * the main thread to retrieve its path.
 171    *
 172    * @param aGlobalObject The JavaScript global.
 173    * @param aErr The error result.
 174    * @param aRequestedDir The directory for which the path is to be retrieved.
 175    *
 176    * @return A promise that resolves to the path of the requested directory.
 177    */
 178   already_AddRefed<Promise> GetDirectoryAsync(const GlobalObject& aGlobalObject,
 179                                               ErrorResult& aErr,
 180                                               const Directory aRequestedDir);
 181
 182  private:
 183   using PopulateDirectoriesPromise = MozPromise<Ok, nsresult, false>;
 184
 185   /**
 186    * Populate the directory cache entry for the requested directory.
 187    *
 188    * @param aRequestedDir The directory cache entry that was requested via
 189    *                      |GetDirectory|.
 190    *
 191    * @return If the requested directory has not been populated, this returns a
 192    *         promise that resolves when the population is complete.
 193    *
 194    *         If the requested directory has already been populated, it returns
 195    *         nullptr instead.
 196    */
 197   already_AddRefed<PopulateDirectoriesPromise> PopulateDirectories(
 198       const Directory aRequestedDir);
 199
 200   /**
 201    * Initialize the requested directory cache entry.
 202    *
 203    * If |Directory::Temp| is requested, all cache entries will be populated.
 204    * Otherwise, only the profile and local profile cache entries will be
 205    * populated. The profile and local profile cache entries have no additional
 206    * overhead for populating them, but the temp directory requires creating a
 207    * directory on the main thread if it has not already happened.
 208    *
 209    * Must be called on the main thread.
 210    *
 211    * @param aRequestedDir The requested directory.
 212    *
 213    * @return The result of initializing directories.
 214    */
 215   nsresult PopulateDirectoriesImpl(const Directory aRequestedDir);
 216
 217   /**
 218    * Resolve the internal PopulateDirectoriesPromise corresponding to
 219    * |aRequestedDir| with the given result.
 220    *
 221    * This will allow all pending queries for the requested directory to resolve
 222    * or be rejected.
 223    *
 224    * @param aRv The return value from PopulateDirectoriesImpl.
 225    * @param aRequestedDir The requested directory cache entry. This is used to
 226    *                      determine which internal MozPromiseHolder we are
 227    * resolving.
 228    */
 229   void ResolvePopulateDirectoriesPromise(nsresult aRv,
 230                                          const Directory aRequestedDir);
 231
 232   /**
 233    * Resolve the given JS promise with the path of the requested directory
 234    *
 235    * Can only be called once the cache entry for the requested directory is
 236    * populated.
 237    *
 238    * @param aPromise The JS promise to resolve.
 239    * @param aRequestedDir The requested directory cache entry.
 240    */
 241   void ResolveWithDirectory(Promise* aPromise, const Directory aRequestedDir);
 242
 243   template <typename T>
 244   using DirectoryArray = EnumeratedArray<Directory, Directory::Count, T>;
 245
 246   DirectoryArray<nsString> mDirectories;
 247   DirectoryArray<MozPromiseHolder<PopulateDirectoriesPromise>> mPromises;
 248
 249   static constexpr DirectoryArray<const char*> kDirectoryNames{
 250       NS_APP_USER_PROFILE_50_DIR,
 251       NS_APP_USER_PROFILE_LOCAL_50_DIR,
 252       NS_OS_TEMP_DIR,
 253       NS_XPCOM_LIBRARY_FILE,
 254   };
 255 };
 256
 257 }  // namespace dom
 258 }  // namespace mozilla
 259
 260 #endif