DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (31ec81b5d7bb)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149
/* vim:set st=2 sts=2 ts=2 et cin: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsIObserverService.h"
#include "mozilla/Services.h"
#include "nsISupportsPrimitives.h"

#include "nsXPCOMCID.h"

#include "nsCategoryCache.h"

nsCategoryObserver::nsCategoryObserver(const char* aCategory,
                                       nsCategoryListener* aListener)
  : mListener(nullptr), mCategory(aCategory), mObserversRemoved(false)
{
  mListener = aListener;

  // First, enumerate the currently existing entries
  nsCOMPtr<nsICategoryManager> catMan =
    do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
  if (!catMan)
    return;

  nsCOMPtr<nsISimpleEnumerator> enumerator;
  nsresult rv = catMan->EnumerateCategory(aCategory,
                                          getter_AddRefs(enumerator));
  if (NS_FAILED(rv))
    return;

  nsTArray<nsCString> entries;
  nsCOMPtr<nsISupports> entry;
  while (NS_SUCCEEDED(enumerator->GetNext(getter_AddRefs(entry)))) {
    nsCOMPtr<nsISupportsCString> entryName = do_QueryInterface(entry, &rv);

    if (NS_SUCCEEDED(rv)) {
      nsAutoCString categoryEntry;
      rv = entryName->GetData(categoryEntry);

      nsCString entryValue;
      catMan->GetCategoryEntry(aCategory,
                               categoryEntry.get(),
                               getter_Copies(entryValue));

      if (NS_SUCCEEDED(rv)) {
        mHash.Put(categoryEntry, entryValue);
        entries.AppendElement(entryValue);
      }
    }
  }

  // Now, listen for changes
  nsCOMPtr<nsIObserverService> serv =
    mozilla::services::GetObserverService();
  if (serv) {
    serv->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
    serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID, false);
    serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID, false);
    serv->AddObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID, false);
  }

  for (int32_t i = entries.Length() - 1; i >= 0; --i)
    mListener->EntryAdded(entries[i]);
}

nsCategoryObserver::~nsCategoryObserver() {
}

NS_IMPL_ISUPPORTS1(nsCategoryObserver, nsIObserver)

void
nsCategoryObserver::ListenerDied() {
  mListener = nullptr;
  RemoveObservers();
}

NS_HIDDEN_(void)
nsCategoryObserver::RemoveObservers() {
  if (mObserversRemoved)
    return;

  mObserversRemoved = true;
  nsCOMPtr<nsIObserverService> obsSvc =
    mozilla::services::GetObserverService();
  if (obsSvc) {
    obsSvc->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
    obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID);
    obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID);
    obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID);
  }
}

NS_IMETHODIMP
nsCategoryObserver::Observe(nsISupports* aSubject, const char* aTopic,
                            const PRUnichar* aData) {
  if (!mListener)
    return NS_OK;

  if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {
    mHash.Clear();
    mListener->CategoryCleared();
    RemoveObservers();

    return NS_OK;
  }

  if (!aData ||
      !nsDependentString(aData).Equals(NS_ConvertASCIItoUTF16(mCategory)))
    return NS_OK;

  nsAutoCString str;
  nsCOMPtr<nsISupportsCString> strWrapper(do_QueryInterface(aSubject));
  if (strWrapper)
    strWrapper->GetData(str);

  if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID) == 0) {
    // We may get an add notification even when we already have an entry. This
    // is due to the notification happening asynchronously, so if the entry gets
    // added and an nsCategoryObserver gets instantiated before events get
    // processed, we'd get the notification for an existing entry.
    // Do nothing in that case.
    if (mHash.Get(str, nullptr))
      return NS_OK;

    nsCOMPtr<nsICategoryManager> catMan =
      do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
    if (!catMan)
      return NS_OK;

    nsCString entryValue;
    catMan->GetCategoryEntry(mCategory.get(),
                             str.get(),
                             getter_Copies(entryValue));

    mHash.Put(str, entryValue);
    mListener->EntryAdded(entryValue);
  } else if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID) == 0) {
    nsAutoCString val;
    if (mHash.Get(str, &val)) {
      mHash.Remove(str);
      mListener->EntryRemoved(val);
    }
  } else if (strcmp(aTopic, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID) == 0) {
    mHash.Clear();
    mListener->CategoryCleared();
  }
  return NS_OK;
}