The Tor Browser: toolkit/xre/nsWindowsRestart.cpp@b8a032363ba2 (annotated)

toolkit/xre/nsWindowsRestart.cpp@b8a032363ba2 (annotated)

toolkit/xre/nsWindowsRestart.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* 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/. */
 // This file is not build directly. Instead, it is included in multiple
 // shared objects.
 #ifdef nsWindowsRestart_cpp
 #error "nsWindowsRestart.cpp is not a header file, and must only be included once."
 #else
 #define nsWindowsRestart_cpp
 #endif
 #include "nsUTF8Utils.h"
 #include <shellapi.h>
 // Needed for CreateEnvironmentBlock
 #include <userenv.h>
 #pragma comment(lib, "userenv.lib")
 /**
  * Get the length that the string will take and takes into account the
  * additional length if the string needs to be quoted and if characters need to
  * be escaped.
  */
 static int ArgStrLen(const wchar_t *s)
 {
   int backslashes = 0;
   int i = wcslen(s);
   BOOL hasDoubleQuote = wcschr(s, L'"') != nullptr;
   // Only add doublequotes if the string contains a space or a tab
   BOOL addDoubleQuotes = wcspbrk(s, L" \t") != nullptr;
   if (addDoubleQuotes) {
     i += 2; // initial and final duoblequote
   }
   if (hasDoubleQuote) {
     while (*s) {
       if (*s == '\\') {
         ++backslashes;
       } else {
         if (*s == '"') {
           // Escape the doublequote and all backslashes preceding the doublequote
           i += backslashes + 1;
         }
         backslashes = 0;
       }
       ++s;
     }
   }
   return i;
 }
 /**
  * Copy string "s" to string "d", quoting the argument as appropriate and
  * escaping doublequotes along with any backslashes that immediately precede
  * doublequotes.
  * The CRT parses this to retrieve the original argc/argv that we meant,
  * see STDARGV.C in the MSVC CRT sources.
  *
  * @return the end of the string
  */
 static wchar_t* ArgToString(wchar_t *d, const wchar_t *s)
 {
   int backslashes = 0;
   BOOL hasDoubleQuote = wcschr(s, L'"') != nullptr;
   // Only add doublequotes if the string contains a space or a tab
   BOOL addDoubleQuotes = wcspbrk(s, L" \t") != nullptr;
   if (addDoubleQuotes) {
     *d = '"'; // initial doublequote
     ++d;
   }
   if (hasDoubleQuote) {
     int i;
     while (*s) {
       if (*s == '\\') {
         ++backslashes;
       } else {
         if (*s == '"') {
           // Escape the doublequote and all backslashes preceding the doublequote
           for (i = 0; i <= backslashes; ++i) {
             *d = '\\';
             ++d;
           }
         }
         backslashes = 0;
       }
       *d = *s;
       ++d; ++s;
     }
   } else {
     wcscpy(d, s);
     d += wcslen(s);
   }
   if (addDoubleQuotes) {
     *d = '"'; // final doublequote
     ++d;
   }
   return d;
 }
 /**
  * Creates a command line from a list of arguments. The returned
  * string is allocated with "malloc" and should be "free"d.
  *
  * argv is UTF8
  */
 wchar_t*
 MakeCommandLine(int argc, wchar_t **argv)
 {
   int i;
   int len = 0;
   // The + 1 of the last argument handles the allocation for null termination
   for (i = 0; i < argc; ++i)
     len += ArgStrLen(argv[i]) + 1;
   // Protect against callers that pass 0 arguments
   if (len == 0)
     len = 1;
   wchar_t *s = (wchar_t*) malloc(len * sizeof(wchar_t));
   if (!s)
     return nullptr;
   wchar_t *c = s;
   for (i = 0; i < argc; ++i) {
     c = ArgToString(c, argv[i]);
     if (i + 1 != argc) {
       *c = ' ';
       ++c;
     }
   }
   *c = '\0';
   return s;
 }
 /**
  * Convert UTF8 to UTF16 without using the normal XPCOM goop, which we
  * can't link to updater.exe.
  */
 static char16_t*
 AllocConvertUTF8toUTF16(const char *arg)
 {
   // UTF16 can't be longer in units than UTF8
   int len = strlen(arg);
   char16_t *s = new char16_t[(len + 1) * sizeof(char16_t)];
   if (!s)
     return nullptr;
   ConvertUTF8toUTF16 convert(s);
   convert.write(arg, len);
   convert.write_terminator();
   return s;
 }
 static void
 FreeAllocStrings(int argc, wchar_t **argv)
 {
   while (argc) {
     --argc;
     delete [] argv[argc];
   }
   delete [] argv;
 }
 /**
  * Launch a child process with the specified arguments.
  * @note argv[0] is ignored
  * @note The form of this function that takes char **argv expects UTF-8
  */
 BOOL
 WinLaunchChild(const wchar_t *exePath,
                int argc, wchar_t **argv,
                HANDLE userToken = nullptr,
                HANDLE *hProcess = nullptr);
 BOOL
 WinLaunchChild(const wchar_t *exePath,
                int argc, char **argv,
                HANDLE userToken,
                HANDLE *hProcess)
 {
   wchar_t** argvConverted = new wchar_t*[argc];
   if (!argvConverted)
     return FALSE;
   for (int i = 0; i < argc; ++i) {
       argvConverted[i] = reinterpret_cast<wchar_t*>(AllocConvertUTF8toUTF16(argv[i]));
     if (!argvConverted[i]) {
       FreeAllocStrings(i, argvConverted);
       return FALSE;
     }
   }
   BOOL ok = WinLaunchChild(exePath, argc, argvConverted, userToken, hProcess);
   FreeAllocStrings(argc, argvConverted);
   return ok;
 }
 BOOL
 WinLaunchChild(const wchar_t *exePath,
                int argc,
                wchar_t **argv,
                HANDLE userToken,
                HANDLE *hProcess)
 {
   wchar_t *cl;
   BOOL ok;
   cl = MakeCommandLine(argc, argv);
   if (!cl) {
     return FALSE;
   }
   STARTUPINFOW si = {0};
   si.cb = sizeof(STARTUPINFOW);
   si.lpDesktop = L"winsta0\\Default";
   PROCESS_INFORMATION pi = {0};
   if (userToken == nullptr) {
     ok = CreateProcessW(exePath,
                         cl,
                         nullptr,  // no special security attributes
                         nullptr,  // no special thread attributes
                         FALSE, // don't inherit filehandles
 ,     // creation flags
                         nullptr,  // inherit my environment
                         nullptr,  // use my current directory
                         &si,
                         &pi);
   } else {
     // Create an environment block for the process we're about to start using
     // the user's token.
     LPVOID environmentBlock = nullptr;
     if (!CreateEnvironmentBlock(&environmentBlock, userToken, TRUE)) {
       environmentBlock = nullptr;
     }
     ok = CreateProcessAsUserW(userToken,
                               exePath,
                               cl,
                               nullptr,  // no special security attributes
                               nullptr,  // no special thread attributes
                               FALSE,    // don't inherit filehandles
 ,        // creation flags
                               environmentBlock,
                               nullptr,  // use my current directory
                               &si,
                               &pi);
     if (environmentBlock) {
       DestroyEnvironmentBlock(environmentBlock);
     }
   }
   if (ok) {
     if (hProcess) {
       *hProcess = pi.hProcess; // the caller now owns the HANDLE
     } else {
       CloseHandle(pi.hProcess);
     }
     CloseHandle(pi.hThread);
   } else {
     LPVOID lpMsgBuf = nullptr;
     FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
                   FORMAT_MESSAGE_FROM_SYSTEM |
                   FORMAT_MESSAGE_IGNORE_INSERTS,
                   nullptr,
                   GetLastError(),
                   MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                   (LPTSTR) &lpMsgBuf,
 ,
                   nullptr);
     wprintf(L"Error restarting: %s\n", lpMsgBuf ? lpMsgBuf : L"(null)");
     if (lpMsgBuf)
       LocalFree(lpMsgBuf);
   }
   free(cl);
   return ok;
 }

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toolkit/xre/nsWindowsRestart.cpp@b8a032363ba2 (annotated)

toolkit/xre/nsWindowsRestart.cpp