Bug 1726648 - Add a helper to trim brackets from nsID r=mccr8,smaug

Differential Revision: https://phabricator.services.mozilla.com/D123163

dom/clients/api/Client.cpp

@@ -16,6 +16,7 @@
 #include "mozilla/dom/Promise.h"
 #include "mozilla/dom/WorkerPrivate.h"
 #include "mozilla/dom/WorkerScope.h"
+#include "nsIDUtils.h"
 #include "nsIGlobalObject.h"
 
 namespace mozilla::dom {
@@ -74,12 +75,7 @@ void Client::GetUrl(nsAString& aUrlOut) const {
 }
 
 void Client::GetId(nsAString& aIdOut) const {
-  char buf[NSID_LENGTH];
-  mData->info().id().ToProvidedString(buf);
-  NS_ConvertASCIItoUTF16 uuid(buf);
-
-  // Remove {} and the null terminator
-  aIdOut.Assign(Substring(uuid, 1, NSID_LENGTH - 3));
+  aIdOut = NSID_TrimBracketsUTF16(mData->info().id());
 }
 
 ClientType Client::Type() const { return mData->info().type(); }

dom/file/uri/BlobURLProtocolHandler.cpp

@@ -28,6 +28,7 @@
 #include "nsContentUtils.h"
 #include "nsError.h"
 #include "nsIAsyncShutdown.h"
+#include "nsIDUtils.h"
 #include "nsIException.h"  // for nsIStackFrame
 #include "nsIMemoryReporter.h"
 #include "nsIPrincipal.h"
@@ -712,9 +713,6 @@ nsresult BlobURLProtocolHandler::GenerateURIString(nsIPrincipal* aPrincipal,
   rv = uuidgen->GenerateUUIDInPlace(&id);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  char chars[NSID_LENGTH];
-  id.ToProvidedString(chars);
-
   aUri.AssignLiteral(BLOBURI_SCHEME);
   aUri.Append(':');
 
@@ -729,7 +727,7 @@ nsresult BlobURLProtocolHandler::GenerateURIString(nsIPrincipal* aPrincipal,
     aUri.Append('/');
   }
 
-  aUri += Substring(chars + 1, chars + NSID_LENGTH - 2);
+  aUri += NSID_TrimBracketsASCII(id);
 
   return NS_OK;
 }

dom/file/uri/FontTableURIProtocolHandler.cpp

@@ -5,6 +5,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "FontTableURIProtocolHandler.h"
+#include "nsIDUtils.h"
 #include "nsIUUIDGenerator.h"
 #include "nsNetUtil.h"
 #include "nsSimpleURI.h"
@@ -23,13 +24,10 @@ nsresult FontTableURIProtocolHandler::GenerateURIString(nsACString& aUri) {
   rv = uuidgen->GenerateUUIDInPlace(&id);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  char chars[NSID_LENGTH];
-  id.ToProvidedString(chars);
-
   aUri = FONTTABLEURI_SCHEME;
   aUri.Append(':');
 
-  aUri += Substring(chars + 1, chars + NSID_LENGTH - 2);
+  aUri += NSID_TrimBracketsASCII(id);
 
   return NS_OK;
 }

dom/filesystem/compat/FileSystem.cpp

@@ -8,6 +8,7 @@
 #include "FileSystemRootDirectoryEntry.h"
 #include "mozilla/dom/FileSystemBinding.h"
 #include "nsContentUtils.h"
+#include "nsIDUtils.h"
 
 namespace mozilla::dom {
 
@@ -33,15 +34,9 @@ already_AddRefed<FileSystem> FileSystem::Create(nsIGlobalObject* aGlobalObject)
     return nullptr;
   }
 
-  char chars[NSID_LENGTH];
-  id.ToProvidedString(chars);
+  NSID_TrimBracketsUTF16 name(id);
 
-  // Any fileSystem has an unique ID. We use UUID, but our generator produces
-  // UUID in this format '{' + UUID + '}'. We remove them with these +1 and -2.
-  nsAutoCString name(Substring(chars + 1, chars + NSID_LENGTH - 2));
-
-  RefPtr<FileSystem> fs =
-      new FileSystem(aGlobalObject, NS_ConvertUTF8toUTF16(name));
+  RefPtr<FileSystem> fs = new FileSystem(aGlobalObject, name);
 
   return fs.forget();
 }

dom/locks/LockManager.cpp

@@ -14,6 +14,7 @@
 #include "mozilla/dom/Promise-inl.h"
 #include "mozilla/dom/WorkerPrivate.h"
 #include "nsIRunnable.h"
+#include "nsIDUtils.h"
 
 namespace mozilla::dom {
 
@@ -66,16 +67,8 @@ static bool HasStorageAccess(nsIGlobalObject* aGlobal) {
   return access > StorageAccess::eDeny;
 }
 
-// XXX: This is copied from ServiceWorkerManager and should go to nsID.
 static nsString GetClientId(nsIGlobalObject* aGlobal) {
-  nsString id;
-  char buf[NSID_LENGTH];
-  aGlobal->GetClientInfo()->Id().ToProvidedString(buf);
-  NS_ConvertASCIItoUTF16 uuid(buf);
-
-  // Remove {} and the null terminator
-  id.Assign(Substring(uuid, 1, NSID_LENGTH - 3));
-  return id;
+  return NSID_TrimBracketsUTF16(aGlobal->GetClientInfo()->Id());
 }
 
 static bool ValidateRequestArguments(const nsAString& name,

dom/media/webrtc/MediaEngineWebRTCAudio.cpp

@@ -15,6 +15,7 @@
 #include "mozilla/Assertions.h"
 #include "mozilla/ErrorNames.h"
 #include "nsContentUtils.h"
+#include "nsIDUtils.h"
 #include "transport/runnable_utils.h"
 #include "Tracing.h"
 
@@ -1307,8 +1308,6 @@ nsString MediaEngineWebRTCAudioCaptureSource::GetName() const {
 
 nsCString MediaEngineWebRTCAudioCaptureSource::GetUUID() const {
   nsID uuid;
-  char uuidBuffer[NSID_LENGTH];
-  nsCString asciiString;
   ErrorResult rv;
 
   rv = nsContentUtils::GenerateUUIDInPlace(uuid);
@@ -1316,11 +1315,7 @@ nsCString MediaEngineWebRTCAudioCaptureSource::GetUUID() const {
     return ""_ns;
   }
 
-  uuid.ToProvidedString(uuidBuffer);
-  asciiString.AssignASCII(uuidBuffer);
-
-  // Remove {} and the null terminator
-  return nsCString(Substring(asciiString, 1, NSID_LENGTH - 3));
+  return NSID_TrimBracketsASCII(uuid);
 }
 
 nsString MediaEngineWebRTCAudioCaptureSource::GetGroupId() const {

dom/payments/PaymentRequest.cpp

@@ -19,6 +19,7 @@
 #include "mozilla/intl/MozLocale.h"
 #include "mozilla/StaticPrefs_dom.h"
 #include "nsContentUtils.h"
+#include "nsIDUtils.h"
 #include "nsImportModule.h"
 #include "nsIRegion.h"
 #include "nsIScriptError.h"
@@ -650,13 +651,7 @@ already_AddRefed<PaymentRequest> PaymentRequest::CreatePaymentRequest(
     return nullptr;
   }
 
-  // Build a string in {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} format
-  char buffer[NSID_LENGTH];
-  uuid.ToProvidedString(buffer);
-
-  // Remove {} and the null terminator
-  nsAutoString id;
-  id.AssignASCII(&buffer[1], NSID_LENGTH - 3);
+  NSID_TrimBracketsUTF16 id(uuid);
 
   // Create payment request with generated id
   RefPtr<PaymentRequest> request = new PaymentRequest(aWindow, id);

dom/serviceworkers/ServiceWorkerManager.cpp

@@ -65,6 +65,7 @@
 
 #include "nsComponentManagerUtils.h"
 #include "nsContentUtils.h"
+#include "nsIDUtils.h"
 #include "nsNetUtil.h"
 #include "nsProxyRelease.h"
 #include "nsQueryObject.h"
@@ -1946,14 +1947,9 @@ class ContinueDispatchFetchEventRunnable : public Runnable {
     nsString clientId;
     nsString resultingClientId;
     nsCOMPtr<nsILoadInfo> loadInfo = channel->LoadInfo();
-    char buf[NSID_LENGTH];
     Maybe<ClientInfo> clientInfo = loadInfo->GetClientInfo();
     if (clientInfo.isSome()) {
-      clientInfo.ref().Id().ToProvidedString(buf);
-      NS_ConvertASCIItoUTF16 uuid(buf);
-
-      // Remove {} and the null terminator
-      clientId.Assign(Substring(uuid, 1, NSID_LENGTH - 3));
+      clientId = NSID_TrimBracketsUTF16(clientInfo->Id());
     }
 
     // Having an initial or reserved client are mutually exclusive events:
@@ -1971,10 +1967,7 @@ class ContinueDispatchFetchEventRunnable : public Runnable {
     }
 
     if (resulting.isSome()) {
-      resulting.ref().Id().ToProvidedString(buf);
-      NS_ConvertASCIItoUTF16 uuid(buf);
-
-      resultingClientId.Assign(Substring(uuid, 1, NSID_LENGTH - 3));
+      resultingClientId = NSID_TrimBracketsUTF16(resulting->Id());
     }
 
     rv = mServiceWorkerPrivate->SendFetchEvent(mChannel, mLoadGroup, clientId,

dom/workers/WorkerPrivate.cpp

@@ -62,6 +62,7 @@
 #include "mozilla/WorkerTimelineMarker.h"
 #include "nsCycleCollector.h"
 #include "nsGlobalWindowInner.h"
+#include "nsIDUtils.h"
 #include "nsNetUtil.h"
 #include "nsIFile.h"
 #include "nsIMemoryReporter.h"
@@ -916,14 +917,8 @@ nsString ComputeWorkerPrivateId() {
   nsID uuid;
   rv = uuidGenerator->GenerateUUIDInPlace(&uuid);
   MOZ_ASSERT(NS_SUCCEEDED(rv));
-  char buffer[NSID_LENGTH];
-  uuid.ToProvidedString(buffer);
 
-  nsString id;
-  // Remove {} and the null terminator
-  id.AssignASCII(&buffer[1], NSID_LENGTH - 3);
-
-  return id;
+  return NSID_TrimBracketsUTF16(uuid);
 }
 
 class WorkerPrivate::EventTarget final : public nsISerialEventTarget {

toolkit/xre/nsAppRunner.cpp

@@ -148,6 +148,7 @@
 #include "nsDirectoryServiceDefs.h"
 #include "nsDirectoryServiceUtils.h"
 #include "nsEmbedCID.h"
+#include "nsIDUtils.h"
 #include "nsNetUtil.h"
 #include "nsReadableUtils.h"
 #include "nsXPCOM.h"
@@ -2798,9 +2799,6 @@ static void SubmitDowngradeTelemetry(const nsCString& aLastVersion,
   rv = uuidGen->GenerateUUIDInPlace(&uuid);
   NS_ENSURE_SUCCESS_VOID(rv);
 
-  char strid[NSID_LENGTH];
-  uuid.ToProvidedString(strid);
-
   nsCString arch("null");
   nsCOMPtr<nsIPropertyBag2> sysInfo =
       do_GetService("@mozilla.org/system-info;1");
@@ -2812,9 +2810,7 @@ static void SubmitDowngradeTelemetry(const nsCString& aLastVersion,
   char date[sizeof "YYYY-MM-DDThh:mm:ss.000Z"];
   strftime(date, sizeof date, "%FT%T.000Z", gmtime(&now));
 
-  // NSID_LENGTH includes the trailing \0 and we also want to strip off the
-  // surrounding braces so the length becomes NSID_LENGTH - 3.
-  nsDependentCSubstring pingId(strid + 1, NSID_LENGTH - 3);
+  NSID_TrimBracketsASCII pingId(uuid);
   constexpr auto pingType = "downgrade"_ns;
 
   int32_t pos = aLastVersion.Find("_");

widget/windows/ToastNotificationHandler.cpp

@@ -14,6 +14,7 @@
 #include "mozilla/WindowsVersion.h"
 #include "mozilla/gfx/2D.h"
 #include "nsDirectoryServiceDefs.h"
+#include "nsIDUtils.h"
 #include "nsIStringBundle.h"
 #include "nsIURI.h"
 #include "nsIUUIDGenerator.h"
@@ -545,10 +546,7 @@ nsresult ToastNotificationHandler::AsyncSaveImage(imgIRequest* aRequest) {
     return rv;
   }
 
-  char uuidChars[NSID_LENGTH];
-  uuid.ToProvidedString(uuidChars);
-  // Remove the brackets at the beginning and ending of the generated UUID.
-  nsAutoCString uuidStr(Substring(uuidChars + 1, uuidChars + NSID_LENGTH - 2));
+  NSID_TrimBracketsASCII uuidStr(uuid);
   uuidStr.AppendLiteral(".bmp");
   mImageFile->AppendNative(uuidStr);
 

xpcom/base/moz.build

@@ -76,6 +76,7 @@ EXPORTS += [
     "nsGZFileWriter.h",
     "nsIClassInfoImpl.h",
     "nsID.h",
+    "nsIDUtils.h",
     "nsIInterfaceRequestorUtils.h",
     "nsINIParser.h",
     "nsInterfaceRequestorAgg.h",

xpcom/base/nsIDUtils.h

@@ -0,0 +1,32 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef XPCOM_BASE_NSIDUTILS_H_
+#define XPCOM_BASE_NSIDUTILS_H_
+
+#include "nsID.h"
+#include "nsString.h"
+#include "nsTString.h"
+
+/**
+ * Trims the brackets around the nsID string, since it wraps its ID with
+ * brackets: {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}.
+ */
+template <typename T>
+class NSID_TrimBrackets : public nsTAutoString<T> {
+ public:
+  explicit NSID_TrimBrackets(const nsID& aID) {
+    nsIDToCString toCString(aID);
+    // The string from nsIDToCString::get() includes a null terminator.
+    // Thus this trims 3 characters: `{`, `}`, and the null terminator.
+    this->AssignASCII(toCString.get() + 1, NSID_LENGTH - 3);
+  }
+};
+
+using NSID_TrimBracketsUTF16 = NSID_TrimBrackets<char16_t>;
+using NSID_TrimBracketsASCII = NSID_TrimBrackets<char>;
+
+#endif  // XPCOM_BASE_NSIDUTILS_H_

xpcom/tests/gtest/TestIDUtils.cpp

@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 "nsID.h"
+#include "nsIDUtils.h"
+
+#include "gtest/gtest.h"
+
+static const char* const bare_ids[] = {
+    "5c347b10-d55c-11d1-89b7-006008911b81",
+    "fc347b10-d55c-f1d1-f9b7-006008911b81",
+};
+
+TEST(nsIDUtils, NSID_TrimBracketsUTF16)
+{
+  nsID id{};
+  for (const auto* idstr : bare_ids) {
+    ASSERT_TRUE(id.Parse(idstr));
+
+    NSID_TrimBracketsUTF16 trimmed(id);
+    ASSERT_TRUE(trimmed.EqualsASCII(idstr));
+  }
+}
+
+TEST(nsIDUtils, NSID_TrimBracketsASCII)
+{
+  nsID id{};
+  for (const auto* idstr : bare_ids) {
+    ASSERT_TRUE(id.Parse(idstr));
+
+    NSID_TrimBracketsASCII trimmed(id);
+    ASSERT_TRUE(trimmed.EqualsASCII(idstr));
+  }
+}

xpcom/tests/gtest/moz.build

@@ -24,6 +24,7 @@ UNIFIED_SOURCES += [
     "TestFile.cpp",
     "TestGCPostBarriers.cpp",
     "TestID.cpp",
+    "TestIDUtils.cpp",
     "TestInputStreamLengthHelper.cpp",
     "TestLogCommandLineHandler.cpp",
     "TestLogging.cpp",