diff options
Diffstat (limited to 'comphelper/source/windows')
| -rw-r--r-- | comphelper/source/windows/windows_process.cxx | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/comphelper/source/windows/windows_process.cxx b/comphelper/source/windows/windows_process.cxx new file mode 100644 index 0000000000..7588bae027 --- /dev/null +++ b/comphelper/source/windows/windows_process.cxx @@ -0,0 +1,262 @@ +/* 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/. */ + +#define WIN32_LEAN_AND_MEAN +#include <windows.h> + +#include <cstring> +#include <wchar.h> + +#include <comphelper/windowsStart.hxx> + +// 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 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 doublequote + } + + if (hasDoubleQuote) + { + int backslashes = 0; + 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) +{ + 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 backslashes = 0; + while (*s) + { + if (*s == '\\') + { + ++backslashes; + } + else + { + if (*s == '"') + { + // Escape the doublequote and all backslashes preceding the doublequote + for (int 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 && argv[i]; ++i) + len += ArgStrLen(argv[i]) + 1; + + // Protect against callers that pass 0 arguments + if (len == 0) + len = 1; + + wchar_t *s = static_cast<wchar_t*>(malloc(len * sizeof(wchar_t))); + if (!s) + return nullptr; + + wchar_t *c = s; + for (i = 0; i < argc && argv[i]; ++i) + { + c = ArgToString(c, argv[i]); + if (i + 1 != argc) + { + *c = ' '; + ++c; + } + } + + *c = '\0'; + + return s; +} + +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; + std::memset(&si, 0, sizeof si); + si.cb = sizeof(STARTUPINFOW); + si.lpDesktop = const_cast<LPWSTR>(L"winsta0\\Default"); + PROCESS_INFORMATION pi; + std::memset(&pi, 0, sizeof pi); + + if (userToken == nullptr) + { + ok = CreateProcessW(exePath, + cl, + nullptr, // no special security attributes + nullptr, // no special thread attributes + FALSE, // don't inherit filehandles + 0, // 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 + 0, // 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; + FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | + FORMAT_MESSAGE_FROM_SYSTEM | + FORMAT_MESSAGE_IGNORE_INSERTS, + nullptr, + GetLastError(), + MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), + reinterpret_cast<LPWSTR>(&lpMsgBuf), + 0, + nullptr); + wprintf(L"Error restarting: %s\n", lpMsgBuf ? lpMsgBuf : L"(null)"); + if (lpMsgBuf) + HeapFree(GetProcessHeap(), 0, lpMsgBuf); + } + + free(cl); + + return ok; +} |