C++ nsCOMPtr::Create方法代码示例

// (static) Obtains the ICO file for the favicon at page aFaviconPageURI
// If successful, the file path on disk is in the format:
// <ProfLDS>\jumpListCache\<hash(aFaviconPageURI)>.ico
nsresult JumpListShortcut::GetOutputIconPath(nsCOMPtr<nsIURI> aFaviconPageURI,
        nsCOMPtr<nsIFile> &aICOFile)
{
    // Hash the input URI and replace any / with _
    nsCAutoString inputURIHash;
    nsCOMPtr<nsICryptoHash> cryptoHash;
    nsresult rv = JumpListItem::HashURI(cryptoHash, aFaviconPageURI,
                                        inputURIHash);
    NS_ENSURE_SUCCESS(rv, rv);
    char* cur = inputURIHash.BeginWriting();
    char* end = inputURIHash.EndWriting();
    for (; cur < end; ++cur) {
        if ('/' == *cur) {
            *cur = '_';
        }
    }

    // Obtain the local profile directory and construct the output icon file path
    rv = NS_GetSpecialDirectory("ProfLDS", getter_AddRefs(aICOFile));
    NS_ENSURE_SUCCESS(rv, rv);
    rv = aICOFile->AppendNative(nsDependentCString(JumpListItem::kJumpListCacheDir));
    NS_ENSURE_SUCCESS(rv, rv);

    // Try to create the directory if it's not there yet
    rv = aICOFile->Create(nsIFile::DIRECTORY_TYPE, 0777);
    if (NS_FAILED(rv) && rv != NS_ERROR_FILE_ALREADY_EXISTS) {
        return rv;
    }

    // Append the icon extension
    inputURIHash.Append(".ico");
    rv = aICOFile->AppendNative(inputURIHash);

    return rv;
}

//.........这里部分代码省略.........
            {"XRE_NotifyProfile", (NSFuncPtr*)&XRE_NotifyProfile},
            {"XRE_LockProfileDirectory", (NSFuncPtr*)&XRE_LockProfileDirectory},
            {0, 0}
    };

    rv = XPCOMGlueLoadXULFunctions(nsFuncs);
    if (NS_FAILED(rv)) {
        cerr << "Could not load XUL functions." << endl;
        return 4;
    }

    // strip the filename from xpcom so we have the dir instead
    size_t lastslash = xpcomPath.find_last_of("/\\");
    if (lastslash == string::npos) {
        cerr << "Invalid path to xpcom:" << xpcomPath << "." << endl;
        return 3;
    }
    string xpcomDir = xpcomPath.substr(0, lastslash);

    // create nsILocalFile pointing to xpcomDir
    nsCOMPtr<nsILocalFile> xuldir;
    rv = NS_NewNativeLocalFile(nsCString(xpcomDir.c_str()), PR_FALSE,
                               getter_AddRefs(xuldir));
    if (NS_FAILED(rv)) {
        cerr << "Unable to create nsILocalFile for xuldir " << xpcomDir
             << "." << endl;
        return 6;
    }

    // create nsILocalFile pointing to appdir
    char self[MAX_PATH];
#ifdef WIN32
    GetModuleFileNameA(GetModuleHandle(NULL), self, sizeof(self));
#else
    // TODO: works on linux, need solution for unices which do not support this
    ssize_t len;
    if ((len = readlink("/proc/self/exe", self, sizeof(self)-1)) != -1)
        self[len] = '\0';
#endif
    string selfPath(self);
    lastslash = selfPath.find_last_of("/\\");
    if (lastslash == string::npos) {
        cerr << "Invalid module filename: " << self << "." << endl;
        return 7;
    }

    selfPath = selfPath.substr(0, lastslash);

    nsCOMPtr<nsILocalFile> appdir;
    rv = NS_NewNativeLocalFile(nsCString(selfPath.c_str()), PR_FALSE,
                               getter_AddRefs(appdir));
    if (NS_FAILED(rv)) {
        cerr << "Unable to create nsILocalFile for appdir." << endl;
        return 8;
    }

    // setup profile dir
    nsCString pr(aProfilePath);
    if (!pr.IsEmpty()) {
        rv = NS_NewNativeLocalFile(pr, PR_FALSE,
                                   getter_AddRefs(sProfileDir));
        NS_ENSURE_SUCCESS(rv, rv);
    } else {
        // for now use a subdir under appdir
        nsCOMPtr<nsIFile> profFile;
        rv = appdir->Clone(getter_AddRefs(profFile));
        NS_ENSURE_SUCCESS(rv, rv);
        sProfileDir = do_QueryInterface(profFile);
        sProfileDir->AppendNative(NS_LITERAL_CSTRING("mozembed"));
    }

    // create dir if needed
    PRBool dirExists;
    rv = sProfileDir->Exists(&dirExists);
    NS_ENSURE_SUCCESS(rv, rv);
    if (!dirExists) {
        sProfileDir->Create(nsIFile::DIRECTORY_TYPE, 0700);
    }

    // Lock profile directory
    if (sProfileDir && !sProfileLock) {
        rv = XRE_LockProfileDirectory(sProfileDir, &sProfileLock);
        NS_ENSURE_SUCCESS(rv, rv);
    }

    // init embedding
    rv = XRE_InitEmbedding2(xuldir, appdir,
                           const_cast<MozEmbedDirectoryProvider*>(&kDirectoryProvider));
    if (NS_FAILED(rv)) {
        cerr << "XRE_InitEmbedding2 failed." << endl;
        return 9;
    }

    // initialize profile:
    XRE_NotifyProfile();

    NS_LogTerm();

    return NS_OK;
}

nsresult
ParentRunnable::ReadMetadata()
{
  AssertIsOnIOThread();
  MOZ_ASSERT(mState == eReadyToReadMetadata);

  QuotaManager* qm = QuotaManager::Get();
  MOZ_ASSERT(qm, "We are on the QuotaManager's IO thread");

  nsresult rv =
    qm->EnsureOriginIsInitialized(quota::PERSISTENCE_TYPE_TEMPORARY, mSuffix,
                                  mGroup, mOrigin, getter_AddRefs(mDirectory));
  if (NS_WARN_IF(NS_FAILED(rv))) {
    mResult = JS::AsmJSCache_StorageInitFailure;
    return rv;
  }

  rv = mDirectory->Append(NS_LITERAL_STRING(ASMJSCACHE_DIRECTORY_NAME));
  NS_ENSURE_SUCCESS(rv, rv);

  bool exists;
  rv = mDirectory->Exists(&exists);
  NS_ENSURE_SUCCESS(rv, rv);

  if (!exists) {
    rv = mDirectory->Create(nsIFile::DIRECTORY_TYPE, 0755);
    NS_ENSURE_SUCCESS(rv, rv);
  } else {
    DebugOnly<bool> isDirectory;
    MOZ_ASSERT(NS_SUCCEEDED(mDirectory->IsDirectory(&isDirectory)));
    MOZ_ASSERT(isDirectory, "Should have caught this earlier!");
  }

  rv = mDirectory->Clone(getter_AddRefs(mMetadataFile));
  NS_ENSURE_SUCCESS(rv, rv);

  rv = mMetadataFile->Append(NS_LITERAL_STRING(ASMJSCACHE_METADATA_FILE_NAME));
  NS_ENSURE_SUCCESS(rv, rv);

  rv = mMetadataFile->Exists(&exists);
  NS_ENSURE_SUCCESS(rv, rv);

  if (exists && NS_FAILED(ReadMetadataFile(mMetadataFile, mMetadata))) {
    exists = false;
  }

  if (!exists) {
    // If we are reading, we can't possibly have a cache hit.
    if (mOpenMode == eOpenForRead) {
      return NS_ERROR_FILE_NOT_FOUND;
    }

    // Initialize Metadata with a valid empty state for the LRU cache.
    for (unsigned i = 0; i < Metadata::kNumEntries; i++) {
      Metadata::Entry& entry = mMetadata.mEntries[i];
      entry.mModuleIndex = i;
      entry.clear();
    }
  }

  return NS_OK;
}