xpcom/build/Omnijar.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_Omnijar_h
   8 #define mozilla_Omnijar_h
   9
  10 #include "nscore.h"
  11 #include "nsCOMPtr.h"
  12 #include "nsString.h"
  13 #include "nsIFile.h"
  14 #include "nsZipArchive.h"
  15
  16 #include "mozilla/StaticPtr.h"
  17
  18 namespace mozilla {
  19
  20 class Omnijar {
  21  private:
  22   /**
  23    * Store an nsIFile for an omni.jar. We can store two paths here, one
  24    * for GRE (corresponding to resource://gre/) and one for APP
  25    * (corresponding to resource:/// and resource://app/), but only
  26    * store one when both point to the same location (unified).
  27    */
  28   static StaticRefPtr<nsIFile> sPath[2];
  29
  30   /**
  31    * Cached nsZipArchives for the corresponding sPath
  32    */
  33   static StaticRefPtr<nsZipArchive> sReader[2];
  34
  35   /**
  36    * Cached nsZipArchives for the outer jar, when using nested jars.
  37    * Otherwise nullptr.
  38    */
  39   static StaticRefPtr<nsZipArchive> sOuterReader[2];
  40
  41   /**
  42    * Has Omnijar::Init() been called?
  43    */
  44   static bool sInitialized;
  45
  46   /**
  47    * Is using unified GRE/APP jar?
  48    */
  49   static bool sIsUnified;
  50
  51  public:
  52   enum Type { GRE = 0, APP = 1 };
  53
  54  private:
  55   /**
  56    * Returns whether we are using nested jars.
  57    */
  58   static inline bool IsNested(Type aType) {
  59     MOZ_ASSERT(IsInitialized(), "Omnijar not initialized");
  60     return !!sOuterReader[aType];
  61   }
  62
  63   /**
  64    * Returns a nsZipArchive pointer for the outer jar file when using nested
  65    * jars. Returns nullptr in the same cases GetPath() would, or if not using
  66    * nested jars.
  67    */
  68   static inline already_AddRefed<nsZipArchive> GetOuterReader(Type aType) {
  69     MOZ_ASSERT(IsInitialized(), "Omnijar not initialized");
  70     RefPtr<nsZipArchive> reader = sOuterReader[aType].get();
  71     return reader.forget();
  72   }
  73
  74  public:
  75   /**
  76    * Returns whether SetBase has been called at least once with
  77    * a valid nsIFile
  78    */
  79   static inline bool IsInitialized() { return sInitialized; }
  80
  81   /**
  82    * Initializes the Omnijar API with the given directory or file for GRE and
  83    * APP. Each of the paths given can be:
  84    * - a file path, pointing to the omnijar file,
  85    * - a directory path, pointing to a directory containing an "omni.jar" file,
  86    * - nullptr for autodetection of an "omni.jar" file.
  87    */
  88   static void Init(nsIFile* aGrePath = nullptr, nsIFile* aAppPath = nullptr);
  89
  90   /**
  91    * Like `Init`, but returns a failed nsresult instead of crashing on failure.
  92    */
  93   static nsresult FallibleInit(nsIFile* aGrePath = nullptr,
  94                                nsIFile* aAppPath = nullptr);
  95
  96   /**
  97    * Initializes the Omnijar API for a child process, given its argument
  98    * list, if the `-greomni` flag and optionally also the `-appomni` flag
  99    * is present.  (`-appomni` is absent in the case of a unified jar.)  If
 100    * neither flag is present, the Omnijar API is not initialized.  The
 101    * flags, if present, will be removed from the argument list.
 102    */
 103   static void ChildProcessInit(int& aArgc, char** aArgv);
 104
 105   /**
 106    * Cleans up the Omnijar API
 107    */
 108   static void CleanUp();
 109
 110   /**
 111    * Returns an nsIFile pointing to the omni.jar file for GRE or APP.
 112    * Returns nullptr when there is no corresponding omni.jar.
 113    * Also returns nullptr for APP in the unified case.
 114    */
 115   static inline already_AddRefed<nsIFile> GetPath(Type aType) {
 116     MOZ_ASSERT(IsInitialized(), "Omnijar not initialized");
 117     nsCOMPtr<nsIFile> path = sPath[aType].get();
 118     return path.forget();
 119   }
 120
 121   /**
 122    * Returns whether GRE or APP use an omni.jar. Returns PR_False for
 123    * APP when using an omni.jar in the unified case.
 124    */
 125   static inline bool HasOmnijar(Type aType) {
 126     MOZ_ASSERT(IsInitialized(), "Omnijar not initialized");
 127     return !!sPath[aType];
 128   }
 129
 130   /**
 131    * Returns a nsZipArchive pointer for the omni.jar file for GRE or
 132    * APP. Returns nullptr in the same cases GetPath() would.
 133    */
 134   static inline already_AddRefed<nsZipArchive> GetReader(Type aType) {
 135     MOZ_ASSERT(IsInitialized(), "Omnijar not initialized");
 136     RefPtr<nsZipArchive> reader = sReader[aType].get();
 137     return reader.forget();
 138   }
 139
 140   /**
 141    * Returns a nsZipArchive pointer for the given path IAOI the given
 142    * path is the omni.jar for either GRE or APP.
 143    */
 144   static already_AddRefed<nsZipArchive> GetReader(nsIFile* aPath);
 145
 146   /**
 147    * In the case of a nested omnijar, this returns the inner reader for the
 148    * omnijar if aPath points to the outer archive and aEntry is the omnijar
 149    * entry name. Returns null otherwise.
 150    * In concrete terms: On Android the omnijar is nested inside the apk archive.
 151    * GetReader("path/to.apk") returns the outer reader and GetInnerReader(
 152    * "path/to.apk", "assets/omni.ja") returns the inner reader.
 153    */
 154   static already_AddRefed<nsZipArchive> GetInnerReader(
 155       nsIFile* aPath, const nsACString& aEntry);
 156
 157   /**
 158    * Returns the URI string corresponding to the omni.jar or directory
 159    * for GRE or APP. i.e. jar:/path/to/omni.jar!/ for omni.jar and
 160    * /path/to/base/dir/ otherwise. Returns an empty string for APP in
 161    * the unified case.
 162    * The returned URI is guaranteed to end with a slash.
 163    */
 164   static nsresult GetURIString(Type aType, nsACString& aResult);
 165
 166  private:
 167   /**
 168    * Used internally, respectively by Init() and CleanUp()
 169    */
 170   static nsresult InitOne(nsIFile* aPath, Type aType);
 171   static void CleanUpOne(Type aType);
 172 }; /* class Omnijar */
 173
 174 /**
 175  * Returns whether or not the currently running build is an unpackaged
 176  * developer build. This check is implemented by looking for omni.ja in the
 177  * the obj/dist dir. We use this routine to detect when the build dir will
 178  * use symlinks to the repo and object dir.
 179  */
 180 inline bool IsPackagedBuild() {
 181   return Omnijar::HasOmnijar(mozilla::Omnijar::GRE);
 182 }
 183
 184 } /* namespace mozilla */
 185
 186 #endif /* mozilla_Omnijar_h */