xpcom/build/FileLocation.h

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #ifndef mozilla_FileLocation_h
   6 #define mozilla_FileLocation_h
   7
   8 #include "nsString.h"
   9 #include "nsCOMPtr.h"
  10 #include "nsAutoPtr.h"
  11 #include "nsIFile.h"
  12 #include "nsIURI.h"
  13 #include "FileUtils.h"
  14
  15 class nsZipArchive;
  16 class nsZipItem;
  17
  18 namespace mozilla {
  19
  20 class FileLocation
  21 {
  22 public:
  23   /**
  24    * FileLocation is an helper to handle different kind of file locations
  25    * within Gecko:
  26    * - on filesystems
  27    * - in archives
  28    * - in archives within archives
  29    * As such, it stores a path within an archive, as well as the archive
  30    * path itself, or the complete file path alone when on a filesystem.
  31    * When the archive is in an archive, an nsZipArchive is stored instead
  32    * of a file path.
  33    */
  34   FileLocation() { }
  35
  36   /**
  37    * Constructor for plain files
  38    */
  39   FileLocation(nsIFile *file)
  40   {
  41     Init(file);
  42   }
  43
  44   /**
  45    * Constructors for path within an archive. The archive can be given either
  46    * as nsIFile or nsZipArchive.
  47    */
  48   FileLocation(nsIFile *zip, const char *path)
  49   {
  50     Init(zip, path);
  51   }
  52
  53   FileLocation(nsZipArchive *zip, const char *path)
  54   {
  55     Init(zip, path);
  56   }
  57
  58   /**
  59    * Creates a new file location relative to another one.
  60    */
  61   FileLocation(const FileLocation &file, const char *path = NULL);
  62
  63   /**
  64    * Initialization functions corresponding to constructors
  65    */
  66   void Init(nsIFile *file)
  67   {
  68     mBaseZip = NULL;
  69     mBaseFile = file;
  70     mPath.Truncate();
  71   }
  72
  73   void Init(nsIFile *zip, const char *path)
  74   {
  75     mBaseZip = NULL;
  76     mBaseFile = zip;
  77     mPath = path;
  78   }
  79
  80   void Init(nsZipArchive *zip, const char *path)
  81   {
  82     mBaseZip = zip;
  83     mBaseFile = NULL;
  84     mPath = path;
  85   }
  86
  87   /**
  88    * Returns an URI string corresponding to the file location
  89    */
  90   void GetURIString(nsACString &result) const;
  91
  92   /**
  93    * Returns the base file of the location, where base file is defined as:
  94    * - The file itself when the location is on a filesystem
  95    * - The archive file when the location is in an archive
  96    * - The outer archive file when the location is in an archive in an archive
  97    */
  98   already_AddRefed<nsIFile> GetBaseFile();
  99
 100   /**
 101    * Returns whether the "base file" (see GetBaseFile) is an archive
 102    */
 103   bool IsZip() const
 104   {
 105     return !mPath.IsEmpty();
 106   }
 107
 108   /**
 109    * Returns the path within the archive, when within an archive
 110    */
 111   void GetPath(nsACString &result) const
 112   {
 113     result = mPath;
 114   }
 115
 116   /**
 117    * Boolean value corresponding to whether the file location is initialized
 118    * or not.
 119    */
 120   operator bool() const
 121   {
 122     return mBaseFile || mBaseZip;
 123   }
 124
 125   /**
 126    * Returns whether another FileLocation points to the same resource
 127    */
 128   bool Equals(const FileLocation &file) const;
 129
 130   /**
 131    * Data associated with a FileLocation.
 132    */
 133   class Data
 134   {
 135   public:
 136     /**
 137      * Returns the data size
 138      */
 139     nsresult GetSize(uint32_t *result);
 140
 141     /**
 142      * Copies the data in the given buffer
 143      */
 144     nsresult Copy(char *buf, uint32_t len);
 145   protected:
 146     friend class FileLocation;
 147     nsZipItem *mItem;
 148     nsRefPtr<nsZipArchive> mZip;
 149     mozilla::AutoFDClose mFd;
 150   };
 151
 152   /**
 153    * Returns the data associated with the resource pointed at by the file
 154    * location.
 155    */
 156   nsresult GetData(Data &data);
 157 private:
 158   nsCOMPtr<nsIFile> mBaseFile;
 159   nsRefPtr<nsZipArchive> mBaseZip;
 160   nsCString mPath;
 161 }; /* class FileLocation */
 162
 163 } /* namespace mozilla */
 164
 165 #endif /* mozilla_FileLocation_h */