1 files changed, 544 insertions, 0 deletions
diff --git a/xpcom/base/nsMacUtilsImpl.cpp b/xpcom/base/nsMacUtilsImpl.cpp
new file mode 100644
index 0000000000..ca9c3ed574
--- /dev/null
+++ b/xpcom/base/nsMacUtilsImpl.cpp
@@ -0,0 +1,544 @@
+/* -*- 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/. */
+
+#include "nsMacUtilsImpl.h"
+
+#include "base/command_line.h"
+#include "base/process_util.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/Omnijar.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsCOMPtr.h"
+#include "nsComponentManagerUtils.h"
+#include "nsIFile.h"
+#include "nsServiceManagerUtils.h"
+#include "nsThreadUtils.h"
+#include "nsXULAppAPI.h"
+#include "prenv.h"
+
+#if defined(MOZ_SANDBOX)
+#  include "mozilla/SandboxSettings.h"
+#endif
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <CoreServices/CoreServices.h>
+#if defined(__aarch64__)
+#  include <dlfcn.h>
+#endif
+#include <sys/sysctl.h>
+
+using mozilla::StaticMutexAutoLock;
+using mozilla::Unused;
+
+#if defined(MOZ_SANDBOX) || defined(__aarch64__)
+// For thread safe setting/checking of sCachedAppPath
+static StaticMutex sCachedAppPathMutex;
+
+// Cache the appDir returned from GetAppPath to avoid doing I/O
+static StaticAutoPtr<nsCString> sCachedAppPath
+    MOZ_GUARDED_BY(sCachedAppPathMutex);
+#endif
+
+// The cached machine architectures of the .app bundle which can
+// be multiple architectures for universal binaries.
+static std::atomic<uint32_t> sBundleArchMaskAtomic = 0;
+
+#if defined(__aarch64__)
+// Limit XUL translation to one attempt
+static std::atomic<bool> sIsXULTranslated = false;
+#endif
+
+// Info.plist key associated with the developer repo path
+#define MAC_DEV_REPO_KEY "MozillaDeveloperRepoPath"
+// Info.plist key associated with the developer repo object directory
+#define MAC_DEV_OBJ_KEY "MozillaDeveloperObjPath"
+
+// Workaround this constant not being available in the macOS SDK
+#define kCFBundleExecutableArchitectureARM64 0x0100000c
+
+enum TCSMStatus { TCSM_Unknown = 0, TCSM_Available, TCSM_Unavailable };
+
+// Initialize with Unknown until we've checked if TCSM is available to set
+static Atomic<TCSMStatus> sTCSMStatus(TCSM_Unknown);
+
+#if defined(MOZ_SANDBOX) || defined(__aarch64__)
+
+// Utility method to call ClearOnShutdown() on the main thread
+static nsresult ClearCachedAppPathOnShutdown() {
+  MOZ_ASSERT(NS_IsMainThread());
+  ClearOnShutdown(&sCachedAppPath);
+  return NS_OK;
+}
+
+// Get the path to the .app directory (aka bundle) for the parent process.
+// When executing in the child process, this is the outer .app (such as
+// Firefox.app) and not the inner .app containing the child process
+// executable. We don't rely on the actual .app extension to allow for the
+// bundle being renamed.
+bool nsMacUtilsImpl::GetAppPath(nsCString& aAppPath) {
+  StaticMutexAutoLock lock(sCachedAppPathMutex);
+  if (sCachedAppPath) {
+    aAppPath.Assign(*sCachedAppPath);
+    return true;
+  }
+
+  nsAutoCString appPath;
+  nsAutoCString appBinaryPath(
+      (CommandLine::ForCurrentProcess()->argv()[0]).c_str());
+
+  // The binary path resides within the .app dir in Contents/MacOS,
+  // e.g., Firefox.app/Contents/MacOS/firefox. Search backwards in
+  // the binary path for the end of .app path.
+  auto pattern = "/Contents/MacOS/"_ns;
+  nsAutoCString::const_iterator start, end;
+  appBinaryPath.BeginReading(start);
+  appBinaryPath.EndReading(end);
+  if (RFindInReadable(pattern, start, end)) {
+    end = start;
+    appBinaryPath.BeginReading(start);
+
+    // If we're executing in a child process, get the parent .app path
+    // by searching backwards once more. The child executable resides
+    // in Firefox.app/Contents/MacOS/plugin-container/Contents/MacOS.
+    if (!XRE_IsParentProcess()) {
+      if (RFindInReadable(pattern, start, end)) {
+        end = start;
+        appBinaryPath.BeginReading(start);
+      } else {
+        return false;
+      }
+    }
+
+    appPath.Assign(Substring(start, end));
+  } else {
+    return false;
+  }
+
+  nsCOMPtr<nsIFile> app;
+  nsresult rv = NS_NewLocalFile(NS_ConvertUTF8toUTF16(appPath), true,
+                                getter_AddRefs(app));
+  if (NS_FAILED(rv)) {
+    return false;
+  }
+
+  rv = app->Normalize();
+  if (NS_FAILED(rv)) {
+    return false;
+  }
+  app->GetNativePath(aAppPath);
+
+  if (!sCachedAppPath) {
+    sCachedAppPath = new nsCString(aAppPath);
+
+    if (NS_IsMainThread()) {
+      ClearCachedAppPathOnShutdown();
+    } else {
+      NS_DispatchToMainThread(
+          NS_NewRunnableFunction("ClearCachedAppPathOnShutdown",
+                                 [] { ClearCachedAppPathOnShutdown(); }));
+    }
+  }
+
+  return true;
+}
+
+#endif /* MOZ_SANDBOX || __aarch64__ */
+
+#if defined(MOZ_SANDBOX) && defined(DEBUG)
+// If XPCOM_MEM_BLOAT_LOG or XPCOM_MEM_LEAK_LOG is set to a log file
+// path, return the path to the parent directory (where sibling log
+// files will be saved.)
+nsresult nsMacUtilsImpl::GetBloatLogDir(nsCString& aDirectoryPath) {
+  nsAutoCString bloatLog(PR_GetEnv("XPCOM_MEM_BLOAT_LOG"));
+  if (bloatLog.IsEmpty()) {
+    bloatLog = PR_GetEnv("XPCOM_MEM_LEAK_LOG");
+  }
+  if (!bloatLog.IsEmpty() && bloatLog != "1" && bloatLog != "2") {
+    return GetDirectoryPath(bloatLog.get(), aDirectoryPath);
+  }
+  return NS_OK;
+}
+
+// Given a path to a file, return the directory which contains it.
+nsresult nsMacUtilsImpl::GetDirectoryPath(const char* aPath,
+                                          nsCString& aDirectoryPath) {
+  nsresult rv = NS_OK;
+  nsCOMPtr<nsIFile> file = do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = file->InitWithNativePath(nsDependentCString(aPath));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIFile> directoryFile;
+  rv = file->GetParent(getter_AddRefs(directoryFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = directoryFile->Normalize();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (NS_FAILED(directoryFile->GetNativePath(aDirectoryPath))) {
+    MOZ_CRASH("Failed to get path for an nsIFile");
+  }
+  return NS_OK;
+}
+#endif /* MOZ_SANDBOX  && DEBUG */
+
+/* static */
+bool nsMacUtilsImpl::IsTCSMAvailable() {
+  if (sTCSMStatus == TCSM_Unknown) {
+    uint32_t oldVal = 0;
+    size_t oldValSize = sizeof(oldVal);
+    int rv = sysctlbyname("kern.tcsm_available", &oldVal, &oldValSize, NULL, 0);
+    TCSMStatus newStatus;
+    if (rv < 0 || oldVal == 0) {
+      newStatus = TCSM_Unavailable;
+    } else {
+      newStatus = TCSM_Available;
+    }
+    // The value of sysctl kern.tcsm_available is the same for all
+    // threads within the same process. If another thread raced with us
+    // and initialized sTCSMStatus first (changing it from
+    // TCSM_Unknown), we can continue without needing to update it
+    // again. Hence, we ignore compareExchange's return value.
+    Unused << sTCSMStatus.compareExchange(TCSM_Unknown, newStatus);
+  }
+  return (sTCSMStatus == TCSM_Available);
+}
+
+static nsresult EnableTCSM() {
+  uint32_t newVal = 1;
+  int rv = sysctlbyname("kern.tcsm_enable", NULL, 0, &newVal, sizeof(newVal));
+  if (rv < 0) {
+    return NS_ERROR_UNEXPECTED;
+  }
+  return NS_OK;
+}
+
+#if defined(DEBUG)
+static bool IsTCSMEnabled() {
+  uint32_t oldVal = 0;
+  size_t oldValSize = sizeof(oldVal);
+  int rv = sysctlbyname("kern.tcsm_enable", &oldVal, &oldValSize, NULL, 0);
+  return (rv == 0) && (oldVal != 0);
+}
+#endif
+
+/*
+ * Intentionally return void so that failures will be ignored in non-debug
+ * builds. This method uses new sysctls which may not be as thoroughly tested
+ * and we don't want to cause crashes handling the failure due to an OS bug.
+ */
+/* static */
+void nsMacUtilsImpl::EnableTCSMIfAvailable() {
+  if (IsTCSMAvailable()) {
+    if (NS_FAILED(EnableTCSM())) {
+      NS_WARNING("Failed to enable TCSM");
+    }
+    MOZ_ASSERT(IsTCSMEnabled());
+  }
+}
+
+// Returns 0 on error.
+/* static */
+uint32_t nsMacUtilsImpl::GetPhysicalCPUCount() {
+  uint32_t oldVal = 0;
+  size_t oldValSize = sizeof(oldVal);
+  int rv = sysctlbyname("hw.physicalcpu_max", &oldVal, &oldValSize, NULL, 0);
+  if (rv == -1) {
+    return 0;
+  }
+  return oldVal;
+}
+
+/*
+ * Helper function to read a string value for a given key from the .app's
+ * Info.plist.
+ */
+static nsresult GetStringValueFromBundlePlist(const nsAString& aKey,
+                                              nsAutoCString& aValue) {
+  CFBundleRef mainBundle = CFBundleGetMainBundle();
+  if (mainBundle == nullptr) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // Read this app's bundle Info.plist as a dictionary
+  CFDictionaryRef bundleInfoDict = CFBundleGetInfoDictionary(mainBundle);
+  if (bundleInfoDict == nullptr) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsAutoCString keyAutoCString = NS_ConvertUTF16toUTF8(aKey);
+  CFStringRef key = CFStringCreateWithCString(
+      kCFAllocatorDefault, keyAutoCString.get(), kCFStringEncodingUTF8);
+  if (key == nullptr) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CFStringRef value = (CFStringRef)CFDictionaryGetValue(bundleInfoDict, key);
+  CFRelease(key);
+  if (value == nullptr) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CFIndex valueLength = CFStringGetLength(value);
+  if (valueLength == 0) {
+    return NS_ERROR_FAILURE;
+  }
+
+  const char* valueCString =
+      CFStringGetCStringPtr(value, kCFStringEncodingUTF8);
+  if (valueCString) {
+    aValue.Assign(valueCString);
+    return NS_OK;
+  }
+
+  CFIndex maxLength =
+      CFStringGetMaximumSizeForEncoding(valueLength, kCFStringEncodingUTF8) + 1;
+  char* valueBuffer = static_cast<char*>(moz_xmalloc(maxLength));
+
+  if (!CFStringGetCString(value, valueBuffer, maxLength,
+                          kCFStringEncodingUTF8)) {
+    free(valueBuffer);
+    return NS_ERROR_FAILURE;
+  }
+
+  aValue.Assign(valueBuffer);
+  free(valueBuffer);
+  return NS_OK;
+}
+
+/*
+ * Helper function for reading a path string from the .app's Info.plist
+ * and returning a directory object for that path with symlinks resolved.
+ */
+static nsresult GetDirFromBundlePlist(const nsAString& aKey, nsIFile** aDir) {
+  nsresult rv;
+
+  nsAutoCString dirPath;
+  rv = GetStringValueFromBundlePlist(aKey, dirPath);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIFile> dir;
+  rv = NS_NewLocalFile(NS_ConvertUTF8toUTF16(dirPath), false,
+                       getter_AddRefs(dir));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = dir->Normalize();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  bool isDirectory = false;
+  rv = dir->IsDirectory(&isDirectory);
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!isDirectory) {
+    return NS_ERROR_FILE_NOT_DIRECTORY;
+  }
+
+  dir.swap(*aDir);
+  return NS_OK;
+}
+
+nsresult nsMacUtilsImpl::GetRepoDir(nsIFile** aRepoDir) {
+#if defined(MOZ_SANDBOX)
+  MOZ_ASSERT(mozilla::IsDevelopmentBuild());
+#endif
+  return GetDirFromBundlePlist(NS_LITERAL_STRING_FROM_CSTRING(MAC_DEV_REPO_KEY),
+                               aRepoDir);
+}
+
+nsresult nsMacUtilsImpl::GetObjDir(nsIFile** aObjDir) {
+#if defined(MOZ_SANDBOX)
+  MOZ_ASSERT(mozilla::IsDevelopmentBuild());
+#endif
+  return GetDirFromBundlePlist(NS_LITERAL_STRING_FROM_CSTRING(MAC_DEV_OBJ_KEY),
+                               aObjDir);
+}
+
+/* static */
+nsresult nsMacUtilsImpl::GetArchitecturesForBundle(uint32_t* aArchMask) {
+  MOZ_ASSERT(aArchMask);
+
+  *aArchMask = sBundleArchMaskAtomic;
+  if (*aArchMask != 0) {
+    return NS_OK;
+  }
+
+  CFBundleRef mainBundle = ::CFBundleGetMainBundle();
+  if (!mainBundle) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CFArrayRef archList = ::CFBundleCopyExecutableArchitectures(mainBundle);
+  if (!archList) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CFIndex archCount = ::CFArrayGetCount(archList);
+  for (CFIndex i = 0; i < archCount; i++) {
+    CFNumberRef arch =
+        static_cast<CFNumberRef>(::CFArrayGetValueAtIndex(archList, i));
+
+    int archInt = 0;
+    if (!::CFNumberGetValue(arch, kCFNumberIntType, &archInt)) {
+      ::CFRelease(archList);
+      return NS_ERROR_FAILURE;
+    }
+
+    if (archInt == kCFBundleExecutableArchitecturePPC) {
+      *aArchMask |= base::PROCESS_ARCH_PPC;
+    } else if (archInt == kCFBundleExecutableArchitectureI386) {
+      *aArchMask |= base::PROCESS_ARCH_I386;
+    } else if (archInt == kCFBundleExecutableArchitecturePPC64) {
+      *aArchMask |= base::PROCESS_ARCH_PPC_64;
+    } else if (archInt == kCFBundleExecutableArchitectureX86_64) {
+      *aArchMask |= base::PROCESS_ARCH_X86_64;
+    } else if (archInt == kCFBundleExecutableArchitectureARM64) {
+      *aArchMask |= base::PROCESS_ARCH_ARM_64;
+    }
+  }
+
+  ::CFRelease(archList);
+
+  sBundleArchMaskAtomic = *aArchMask;
+
+  return NS_OK;
+}
+
+/* static */
+nsresult nsMacUtilsImpl::GetArchitecturesForBinary(const char* aPath,
+                                                   uint32_t* aArchMask) {
+  MOZ_ASSERT(aArchMask);
+
+  *aArchMask = 0;
+
+  CFURLRef url = ::CFURLCreateFromFileSystemRepresentation(
+      kCFAllocatorDefault, (const UInt8*)aPath, strlen(aPath), false);
+  if (!url) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CFArrayRef archs = ::CFBundleCopyExecutableArchitecturesForURL(url);
+  if (!archs) {
+    CFRelease(url);
+    return NS_ERROR_FAILURE;
+  }
+
+  CFIndex archCount = ::CFArrayGetCount(archs);
+  for (CFIndex i = 0; i < archCount; i++) {
+    CFNumberRef currentArch =
+        static_cast<CFNumberRef>(::CFArrayGetValueAtIndex(archs, i));
+    int currentArchInt = 0;
+    if (!::CFNumberGetValue(currentArch, kCFNumberIntType, &currentArchInt)) {
+      continue;
+    }
+    switch (currentArchInt) {
+      case kCFBundleExecutableArchitectureX86_64:
+        *aArchMask |= base::PROCESS_ARCH_X86_64;
+        break;
+      case kCFBundleExecutableArchitectureARM64:
+        *aArchMask |= base::PROCESS_ARCH_ARM_64;
+        break;
+      default:
+        break;
+    }
+  }
+
+  CFRelease(url);
+  CFRelease(archs);
+
+  // We expect x86 or ARM64 or both.
+  if (*aArchMask == 0) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  return NS_OK;
+}
+
+#if defined(__aarch64__)
+// Pre-translate XUL so that x64 child processes launched after this
+// translation will not incur the translation overhead delaying startup.
+// Returns 1 if translation is in progress, -1 on an error encountered before
+// translation, and otherwise returns the result of rosetta_translate_binaries.
+/* static */
+int nsMacUtilsImpl::PreTranslateXUL() {
+  bool expected = false;
+  if (!sIsXULTranslated.compare_exchange_strong(expected, true)) {
+    // Translation is already done or in progress.
+    return 1;
+  }
+
+  // Get the path to XUL by first getting the
+  // outer .app path and appending the path to XUL.
+  nsCString xulPath;
+  if (!GetAppPath(xulPath)) {
+    return -1;
+  }
+  xulPath.Append("/Contents/MacOS/XUL");
+
+  return PreTranslateBinary(xulPath);
+}
+
+// Use Chromium's method to pre-translate the provided binary using the
+// undocumented function "rosetta_translate_binaries" from libRosetta.dylib.
+// Re-translating the same binary does not cause translation to occur again.
+// Returns -1 on an error encountered before translation, otherwise returns
+// the rosetta_translate_binaries result. This method is partly copied from
+// Chromium code.
+/* static */
+int nsMacUtilsImpl::PreTranslateBinary(nsCString aBinaryPath) {
+  // Do not attempt to use this in child processes. Child
+  // processes executing should already be translated and
+  // sandboxing may interfere with translation.
+  MOZ_ASSERT(XRE_IsParentProcess());
+  if (!XRE_IsParentProcess()) {
+    return -1;
+  }
+
+  // Translation can take several seconds and therefore
+  // should not be done on the main thread.
+  MOZ_ASSERT(!NS_IsMainThread());
+  if (NS_IsMainThread()) {
+    return -1;
+  }
+
+  // @available() is not available for macOS 11 at this time so use
+  // -Wunguarded-availability-new to avoid compiler warnings caused
+  // by an earlier minimum SDK. ARM64 builds require the 11.0 SDK and
+  // can not be run on earlier OS versions so this is not a concern.
+#  pragma clang diagnostic push
+#  pragma clang diagnostic ignored "-Wunguarded-availability-new"
+  // If Rosetta is not installed, do not proceed.
+  if (!CFBundleIsArchitectureLoadable(CPU_TYPE_X86_64)) {
+    return -1;
+  }
+#  pragma clang diagnostic pop
+
+  if (aBinaryPath.IsEmpty()) {
+    return -1;
+  }
+
+  // int rosetta_translate_binaries(const char*[] paths, int npaths)
+  using rosetta_translate_binaries_t = int (*)(const char*[], int);
+
+  static auto rosetta_translate_binaries = []() {
+    void* libRosetta =
+        dlopen("/usr/lib/libRosetta.dylib", RTLD_LAZY | RTLD_LOCAL);
+    if (!libRosetta) {
+      return static_cast<rosetta_translate_binaries_t>(nullptr);
+    }
+
+    return reinterpret_cast<rosetta_translate_binaries_t>(
+        dlsym(libRosetta, "rosetta_translate_binaries"));
+  }();
+
+  if (!rosetta_translate_binaries) {
+    return -1;
+  }
+
+  const char* pathPtr = aBinaryPath.get();
+  return rosetta_translate_binaries(&pathPtr, 1);
+}
+
+#endif