1 files changed, 600 insertions, 0 deletions
diff --git a/xpcom/threads/nsProcessCommon.cpp b/xpcom/threads/nsProcessCommon.cpp
new file mode 100644
index 0000000000..0a88488e5f
--- /dev/null
+++ b/xpcom/threads/nsProcessCommon.cpp
@@ -0,0 +1,600 @@
+/* -*- 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/. */
+
+/*****************************************************************************
+ *
+ * nsProcess is used to execute new processes and specify if you want to
+ * wait (blocking) or continue (non-blocking).
+ *
+ *****************************************************************************
+ */
+
+#include "mozilla/ArrayUtils.h"
+
+#include "nsCOMPtr.h"
+#include "nsIFile.h"
+#include "nsProcess.h"
+#include "prio.h"
+#include "prenv.h"
+#include "nsCRT.h"
+#include "nsThreadUtils.h"
+#include "nsIObserverService.h"
+#include "nsXULAppAPI.h"
+#include "mozilla/Services.h"
+
+#include <stdlib.h>
+
+#if defined(PROCESSMODEL_WINAPI)
+#  include "nsString.h"
+#  include "nsLiteralString.h"
+#  include "nsReadableUtils.h"
+#  include "mozilla/AssembleCmdLine.h"
+#  include "mozilla/UniquePtrExtensions.h"
+#else
+#  ifdef XP_MACOSX
+#    include <crt_externs.h>
+#    include <spawn.h>
+#  endif
+#  ifdef XP_UNIX
+#    ifndef XP_MACOSX
+#      include "base/process_util.h"
+#    endif
+#    include <sys/wait.h>
+#    include <sys/errno.h>
+#  endif
+#  include <sys/types.h>
+#  include <signal.h>
+#endif
+
+using namespace mozilla;
+
+//-------------------------------------------------------------------//
+// nsIProcess implementation
+//-------------------------------------------------------------------//
+NS_IMPL_ISUPPORTS(nsProcess, nsIProcess, nsIObserver)
+
+// Constructor
+nsProcess::nsProcess()
+    : mThread(nullptr),
+      mLock("nsProcess.mLock"),
+      mShutdown(false),
+      mBlocking(false),
+      mStartHidden(false),
+      mNoShell(false),
+      mPid(-1),
+      mExitValue(-1)
+#if !defined(XP_UNIX)
+      ,
+      mProcess(nullptr)
+#endif
+{
+}
+
+// Destructor
+nsProcess::~nsProcess() = default;
+
+NS_IMETHODIMP
+nsProcess::Init(nsIFile* aExecutable) {
+  if (mExecutable) {
+    return NS_ERROR_ALREADY_INITIALIZED;
+  }
+
+  if (NS_WARN_IF(!aExecutable)) {
+    return NS_ERROR_INVALID_ARG;
+  }
+  bool isFile;
+
+  // First make sure the file exists
+  nsresult rv = aExecutable->IsFile(&isFile);
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+  if (!isFile) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // Store the nsIFile in mExecutable
+  mExecutable = aExecutable;
+  // Get the path because it is needed by the NSPR process creation
+#ifdef XP_WIN
+  rv = mExecutable->GetTarget(mTargetPath);
+  if (NS_FAILED(rv) || mTargetPath.IsEmpty())
+#endif
+    rv = mExecutable->GetPath(mTargetPath);
+
+  return rv;
+}
+
+void nsProcess::Monitor(void* aArg) {
+  RefPtr<nsProcess> process = dont_AddRef(static_cast<nsProcess*>(aArg));
+
+  if (!process->mBlocking) {
+    NS_SetCurrentThreadName("RunProcess");
+  }
+
+#if defined(PROCESSMODEL_WINAPI)
+  HANDLE processHandle;
+  {
+    // The mutex region cannot include WaitForSingleObject otherwise we'll
+    // block calls such as Kill. So lock on access and store a local.
+    MutexAutoLock lock(process->mLock);
+    processHandle = process->mProcess;
+  }
+
+  DWORD dwRetVal;
+  unsigned long exitCode = -1;
+
+  dwRetVal = WaitForSingleObject(processHandle, INFINITE);
+  if (dwRetVal != WAIT_FAILED) {
+    if (GetExitCodeProcess(processHandle, &exitCode) == FALSE) {
+      exitCode = -1;
+    }
+  }
+
+  // Lock in case Kill or GetExitCode are called during this.
+  {
+    MutexAutoLock lock(process->mLock);
+    CloseHandle(process->mProcess);
+    process->mProcess = nullptr;
+    process->mExitValue = exitCode;
+    if (process->mShutdown) {
+      return;
+    }
+  }
+#else
+#  ifdef XP_UNIX
+  int exitCode = -1;
+  int status = 0;
+  pid_t result;
+  do {
+    result = waitpid(process->mPid, &status, 0);
+  } while (result == -1 && errno == EINTR);
+  if (result == process->mPid) {
+    if (WIFEXITED(status)) {
+      exitCode = WEXITSTATUS(status);
+    } else if (WIFSIGNALED(status)) {
+      exitCode = 256;  // match NSPR's signal exit status
+    }
+  }
+#  else
+  int32_t exitCode = -1;
+  PRProcess* prProcess;
+  {
+    // The mutex region cannot include PR_WaitProcess otherwise we'll
+    // block calls such as Kill. So lock on access and store a local.
+    MutexAutoLock lock(process->mLock);
+    prProcess = process->mProcess;
+  }
+  if (PR_WaitProcess(prProcess, &exitCode) != PR_SUCCESS) {
+    exitCode = -1;
+  }
+#  endif
+
+  // Lock in case Kill or GetExitCode are called during this
+  {
+    MutexAutoLock lock(process->mLock);
+#  if !defined(XP_UNIX)
+    process->mProcess = nullptr;
+#  endif
+    process->mExitValue = exitCode;
+    if (process->mShutdown) {
+      return;
+    }
+  }
+#endif
+
+  // If we ran a background thread for the monitor then notify on the main
+  // thread
+  if (NS_IsMainThread()) {
+    process->ProcessComplete();
+  } else {
+    NS_DispatchToMainThread(NewRunnableMethod(
+        "nsProcess::ProcessComplete", process, &nsProcess::ProcessComplete));
+  }
+}
+
+void nsProcess::ProcessComplete() {
+  if (mThread) {
+    nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
+    if (os) {
+      os->RemoveObserver(this, "xpcom-shutdown");
+    }
+    PR_JoinThread(mThread);
+    mThread = nullptr;
+  }
+
+  const char* topic;
+  {
+    MutexAutoLock lock(mLock);
+    if (mExitValue != 0) {
+      topic = "process-failed";
+    } else {
+      topic = "process-finished";
+    }
+  }
+
+  mPid = -1;
+  nsCOMPtr<nsIObserver> observer = mObserver.GetValue();
+  mObserver = nullptr;
+
+  if (observer) {
+    observer->Observe(NS_ISUPPORTS_CAST(nsIProcess*, this), topic, nullptr);
+  }
+}
+
+// XXXldb |aArgs| has the wrong const-ness
+NS_IMETHODIMP
+nsProcess::Run(bool aBlocking, const char** aArgs, uint32_t aCount) {
+  return CopyArgsAndRunProcess(aBlocking, aArgs, aCount, nullptr, false);
+}
+
+// XXXldb |aArgs| has the wrong const-ness
+NS_IMETHODIMP
+nsProcess::RunAsync(const char** aArgs, uint32_t aCount, nsIObserver* aObserver,
+                    bool aHoldWeak) {
+  return CopyArgsAndRunProcess(false, aArgs, aCount, aObserver, aHoldWeak);
+}
+
+nsresult nsProcess::CopyArgsAndRunProcess(bool aBlocking, const char** aArgs,
+                                          uint32_t aCount,
+                                          nsIObserver* aObserver,
+                                          bool aHoldWeak) {
+  // Add one to the aCount for the program name and one for null termination.
+  char** my_argv = nullptr;
+  my_argv = (char**)moz_xmalloc(sizeof(char*) * (aCount + 2));
+
+  my_argv[0] = ToNewUTF8String(mTargetPath);
+
+  for (uint32_t i = 0; i < aCount; ++i) {
+    my_argv[i + 1] = const_cast<char*>(aArgs[i]);
+  }
+
+  my_argv[aCount + 1] = nullptr;
+
+  nsresult rv = RunProcess(aBlocking, my_argv, aObserver, aHoldWeak, false);
+
+  free(my_argv[0]);
+  free(my_argv);
+  return rv;
+}
+
+// XXXldb |aArgs| has the wrong const-ness
+NS_IMETHODIMP
+nsProcess::Runw(bool aBlocking, const char16_t** aArgs, uint32_t aCount) {
+  return CopyArgsAndRunProcessw(aBlocking, aArgs, aCount, nullptr, false);
+}
+
+// XXXldb |aArgs| has the wrong const-ness
+NS_IMETHODIMP
+nsProcess::RunwAsync(const char16_t** aArgs, uint32_t aCount,
+                     nsIObserver* aObserver, bool aHoldWeak) {
+  return CopyArgsAndRunProcessw(false, aArgs, aCount, aObserver, aHoldWeak);
+}
+
+nsresult nsProcess::CopyArgsAndRunProcessw(bool aBlocking,
+                                           const char16_t** aArgs,
+                                           uint32_t aCount,
+                                           nsIObserver* aObserver,
+                                           bool aHoldWeak) {
+  // Add one to the aCount for the program name and one for null termination.
+  char** my_argv = nullptr;
+  my_argv = (char**)moz_xmalloc(sizeof(char*) * (aCount + 2));
+
+  my_argv[0] = ToNewUTF8String(mTargetPath);
+
+  for (uint32_t i = 0; i < aCount; i++) {
+    my_argv[i + 1] = ToNewUTF8String(nsDependentString(aArgs[i]));
+  }
+
+  my_argv[aCount + 1] = nullptr;
+
+  nsresult rv = RunProcess(aBlocking, my_argv, aObserver, aHoldWeak, true);
+
+  for (uint32_t i = 0; i <= aCount; ++i) {
+    free(my_argv[i]);
+  }
+  free(my_argv);
+  return rv;
+}
+
+nsresult nsProcess::RunProcess(bool aBlocking, char** aMyArgv,
+                               nsIObserver* aObserver, bool aHoldWeak,
+                               bool aArgsUTF8) {
+  NS_WARNING_ASSERTION(!XRE_IsContentProcess(),
+                       "No launching of new processes in the content process");
+
+  if (NS_WARN_IF(!mExecutable)) {
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+  if (NS_WARN_IF(mThread)) {
+    return NS_ERROR_ALREADY_INITIALIZED;
+  }
+
+  if (aObserver) {
+    if (aHoldWeak) {
+      nsresult rv = NS_OK;
+      mObserver = do_GetWeakReference(aObserver, &rv);
+      NS_ENSURE_SUCCESS(rv, rv);
+    } else {
+      mObserver = aObserver;
+    }
+  }
+
+  {
+    MutexAutoLock lock(mLock);
+    mExitValue = -1;
+    mPid = -1;
+  }
+
+#if defined(PROCESSMODEL_WINAPI)
+  BOOL retVal;
+  UniqueFreePtr<wchar_t> cmdLine;
+
+  // |aMyArgv| is null-terminated and always starts with the program path. If
+  // the second slot is non-null then arguments are being passed.
+  if (aMyArgv[1] || mNoShell) {
+    // Pass the executable path as argv[0] to the launched program when calling
+    // CreateProcess().
+    char** argv = mNoShell ? aMyArgv : aMyArgv + 1;
+
+    wchar_t* assembledCmdLine = nullptr;
+    if (assembleCmdLine(argv, &assembledCmdLine,
+                        aArgsUTF8 ? CP_UTF8 : CP_ACP) == -1) {
+      return NS_ERROR_FILE_EXECUTION_FAILED;
+    }
+    cmdLine.reset(assembledCmdLine);
+  }
+
+  // The program name in aMyArgv[0] is always UTF-8
+  NS_ConvertUTF8toUTF16 wideFile(aMyArgv[0]);
+
+  if (mNoShell) {
+    STARTUPINFO startupInfo;
+    ZeroMemory(&startupInfo, sizeof(startupInfo));
+    startupInfo.cb = sizeof(startupInfo);
+    startupInfo.dwFlags = STARTF_USESHOWWINDOW;
+    startupInfo.wShowWindow = mStartHidden ? SW_HIDE : SW_SHOWNORMAL;
+
+    PROCESS_INFORMATION processInfo;
+    retVal = CreateProcess(/* lpApplicationName = */ wideFile.get(),
+                           /* lpCommandLine */ cmdLine.get(),
+                           /* lpProcessAttributes = */ NULL,
+                           /* lpThreadAttributes = */ NULL,
+                           /* bInheritHandles = */ FALSE,
+                           /* dwCreationFlags = */ 0,
+                           /* lpEnvironment = */ NULL,
+                           /* lpCurrentDirectory = */ NULL,
+                           /* lpStartupInfo = */ &startupInfo,
+                           /* lpProcessInformation */ &processInfo);
+
+    if (!retVal) {
+      return NS_ERROR_FILE_EXECUTION_FAILED;
+    }
+
+    CloseHandle(processInfo.hThread);
+
+    // TODO(bug 1763051): assess if we need further work around this locking.
+    MutexAutoLock lock(mLock);
+    mProcess = processInfo.hProcess;
+  } else {
+    SHELLEXECUTEINFOW sinfo;
+    memset(&sinfo, 0, sizeof(SHELLEXECUTEINFOW));
+    sinfo.cbSize = sizeof(SHELLEXECUTEINFOW);
+    sinfo.hwnd = nullptr;
+    sinfo.lpFile = wideFile.get();
+    sinfo.nShow = mStartHidden ? SW_HIDE : SW_SHOWNORMAL;
+
+    /* The SEE_MASK_NO_CONSOLE flag is important to prevent console windows
+     * from appearing. This makes behavior the same on all platforms. The flag
+     * will not have any effect on non-console applications.
+     */
+    sinfo.fMask =
+        SEE_MASK_FLAG_DDEWAIT | SEE_MASK_NO_CONSOLE | SEE_MASK_NOCLOSEPROCESS;
+
+    if (cmdLine) {
+      sinfo.lpParameters = cmdLine.get();
+    }
+
+    retVal = ShellExecuteExW(&sinfo);
+    if (!retVal) {
+      return NS_ERROR_FILE_EXECUTION_FAILED;
+    }
+
+    MutexAutoLock lock(mLock);
+    mProcess = sinfo.hProcess;
+  }
+
+  {
+    MutexAutoLock lock(mLock);
+    mPid = GetProcessId(mProcess);
+  }
+#elif defined(XP_MACOSX)
+  // Note: |aMyArgv| is already null-terminated as required by posix_spawnp.
+  pid_t newPid = 0;
+  int result = posix_spawnp(&newPid, aMyArgv[0], nullptr, nullptr, aMyArgv,
+                            *_NSGetEnviron());
+  mPid = static_cast<int32_t>(newPid);
+
+  if (result != 0) {
+    return NS_ERROR_FAILURE;
+  }
+#elif defined(XP_UNIX)
+  base::LaunchOptions options;
+  std::vector<std::string> argvVec;
+  for (char** arg = aMyArgv; *arg != nullptr; ++arg) {
+    argvVec.push_back(*arg);
+  }
+  pid_t newPid;
+  if (base::LaunchApp(argvVec, options, &newPid).isOk()) {
+    static_assert(sizeof(pid_t) <= sizeof(int32_t),
+                  "mPid is large enough to hold a pid");
+    mPid = static_cast<int32_t>(newPid);
+  } else {
+    return NS_ERROR_FAILURE;
+  }
+#else
+  {
+    PRProcess* prProcess =
+        PR_CreateProcess(aMyArgv[0], aMyArgv, nullptr, nullptr);
+    if (!prProcess) {
+      return NS_ERROR_FAILURE;
+    }
+    {
+      MutexAutoLock lock(mLock);
+      mProcess = prProcess;
+    }
+    struct MYProcess {
+      uint32_t pid;
+    };
+    MYProcess* ptrProc = (MYProcess*)mProcess;
+    mPid = ptrProc->pid;
+  }
+#endif
+
+  NS_ADDREF_THIS();
+  mBlocking = aBlocking;
+  if (aBlocking) {
+    Monitor(this);
+    MutexAutoLock lock(mLock);
+    if (mExitValue < 0) {
+      return NS_ERROR_FILE_EXECUTION_FAILED;
+    }
+  } else {
+    mThread = CreateMonitorThread();
+    if (!mThread) {
+      NS_RELEASE_THIS();
+      return NS_ERROR_FAILURE;
+    }
+
+    // It isn't a failure if we just can't watch for shutdown
+    nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
+    if (os) {
+      os->AddObserver(this, "xpcom-shutdown", false);
+    }
+  }
+
+  return NS_OK;
+}
+
+// We don't guarantee that monitor threads are joined before Gecko exits, which
+// can cause TSAN to complain about thread leaks. We handle this with a TSAN
+// suppression, and route thread creation through this helper so that the
+// suppression is as narrowly-scoped as possible.
+PRThread* nsProcess::CreateMonitorThread() {
+  return PR_CreateThread(PR_SYSTEM_THREAD, Monitor, this, PR_PRIORITY_NORMAL,
+                         PR_GLOBAL_THREAD, PR_JOINABLE_THREAD, 0);
+}
+
+NS_IMETHODIMP
+nsProcess::GetIsRunning(bool* aIsRunning) {
+  if (mThread) {
+    *aIsRunning = true;
+  } else {
+    *aIsRunning = false;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::GetStartHidden(bool* aStartHidden) {
+  *aStartHidden = mStartHidden;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::SetStartHidden(bool aStartHidden) {
+  mStartHidden = aStartHidden;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::GetNoShell(bool* aNoShell) {
+  *aNoShell = mNoShell;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::SetNoShell(bool aNoShell) {
+  mNoShell = aNoShell;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::GetPid(uint32_t* aPid) {
+  if (!mThread) {
+    return NS_ERROR_FAILURE;
+  }
+  if (mPid < 0) {
+    return NS_ERROR_NOT_IMPLEMENTED;
+  }
+  *aPid = mPid;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::Kill() {
+  if (!mThread) {
+    return NS_ERROR_FAILURE;
+  }
+
+  {
+    MutexAutoLock lock(mLock);
+#if defined(PROCESSMODEL_WINAPI)
+    if (TerminateProcess(mProcess, 0) == 0) {
+      return NS_ERROR_FAILURE;
+    }
+#elif defined(XP_UNIX)
+    if (kill(mPid, SIGKILL) != 0) {
+      return NS_ERROR_FAILURE;
+    }
+#else
+    if (!mProcess || (PR_KillProcess(mProcess) != PR_SUCCESS)) {
+      return NS_ERROR_FAILURE;
+    }
+#endif
+  }
+
+  // We must null out mThread if we want IsRunning to return false immediately
+  // after this call.
+  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
+  if (os) {
+    os->RemoveObserver(this, "xpcom-shutdown");
+  }
+  PR_JoinThread(mThread);
+  mThread = nullptr;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::GetExitValue(int32_t* aExitValue) {
+  MutexAutoLock lock(mLock);
+
+  *aExitValue = mExitValue;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsProcess::Observe(nsISupports* aSubject, const char* aTopic,
+                   const char16_t* aData) {
+  // Shutting down, drop all references
+  if (mThread) {
+    nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
+    if (os) {
+      os->RemoveObserver(this, "xpcom-shutdown");
+    }
+    mThread = nullptr;
+  }
+
+  mObserver = nullptr;
+
+  MutexAutoLock lock(mLock);
+  mShutdown = true;
+
+  return NS_OK;
+}