-// Copyright (c) 2011-2012 Ryan Prichard
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to
-// deal in the Software without restriction, including without limitation the
-// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
-// sell copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
-// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
-// IN THE SOFTWARE.
-
-#include "DebugClient.h"
-
-#include <windows.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <algorithm>
-#include <string>
-
-#include "winpty_snprintf.h"
-
-const wchar_t *const kPipeName = L"\\\\.\\pipe\\DebugServer";
-
-void *volatile g_debugConfig;
-
-namespace {
-
-// It would be easy to accidentally trample on the Windows LastError value
-// by adding logging/debugging code. Ensure that can't happen by saving and
-// restoring the value. This saving and restoring doesn't happen along the
-// fast path.
-class PreserveLastError {
-public:
- PreserveLastError() : m_lastError(GetLastError()) {}
- ~PreserveLastError() { SetLastError(m_lastError); }
-private:
- DWORD m_lastError;
-};
-
-} // anonymous namespace
-
-static void sendToDebugServer(const char *message)
-{
- HANDLE tracePipe = INVALID_HANDLE_VALUE;
-
- do {
- // The default impersonation level is SECURITY_IMPERSONATION, which allows
- // a sufficiently authorized named pipe server to impersonate the client.
- // There's no need for impersonation in this debugging system, so reduce
- // the impersonation level to SECURITY_IDENTIFICATION, which allows a
- // server to merely identify us.
- tracePipe = CreateFileW(
- kPipeName,
- GENERIC_READ | GENERIC_WRITE,
- 0, NULL, OPEN_EXISTING,
- SECURITY_SQOS_PRESENT | SECURITY_IDENTIFICATION,
- NULL);
- } while (tracePipe == INVALID_HANDLE_VALUE &&
- GetLastError() == ERROR_PIPE_BUSY &&
- WaitNamedPipeW(kPipeName, NMPWAIT_WAIT_FOREVER));
-
- if (tracePipe != INVALID_HANDLE_VALUE) {
- DWORD newMode = PIPE_READMODE_MESSAGE;
- SetNamedPipeHandleState(tracePipe, &newMode, NULL, NULL);
- char response[16];
- DWORD actual = 0;
- TransactNamedPipe(tracePipe,
- const_cast<char*>(message), strlen(message),
- response, sizeof(response), &actual, NULL);
- CloseHandle(tracePipe);
- }
-}
-
-// Get the current UTC time as milliseconds from the epoch (ignoring leap
-// seconds). Use the Unix epoch for consistency with DebugClient.py. There
-// are 134774 days between 1601-01-01 (the Win32 epoch) and 1970-01-01 (the
-// Unix epoch).
-static long long unixTimeMillis()
-{
- FILETIME fileTime;
- GetSystemTimeAsFileTime(&fileTime);
- long long msTime = (((long long)fileTime.dwHighDateTime << 32) +
- fileTime.dwLowDateTime) / 10000;
- return msTime - 134774LL * 24 * 3600 * 1000;
-}
-
-static const char *getDebugConfig()
-{
- if (g_debugConfig == NULL) {
- PreserveLastError preserve;
- const int bufSize = 256;
- char buf[bufSize];
- DWORD actualSize =
- GetEnvironmentVariableA("WINPTY_DEBUG", buf, bufSize);
- if (actualSize == 0 || actualSize >= static_cast<DWORD>(bufSize)) {
- buf[0] = '\0';
- }
- const size_t len = strlen(buf) + 1;
- char *newConfig = new char[len];
- std::copy(buf, buf + len, newConfig);
- void *oldValue = InterlockedCompareExchangePointer(
- &g_debugConfig, newConfig, NULL);
- if (oldValue != NULL) {
- delete [] newConfig;
- }
- }
- return static_cast<const char*>(g_debugConfig);
-}
-
-bool isTracingEnabled()
-{
- static bool disabled, enabled;
- if (disabled) {
- return false;
- } else if (enabled) {
- return true;
- } else {
- // Recognize WINPTY_DEBUG=1 for backwards compatibility.
- PreserveLastError preserve;
- bool value = hasDebugFlag("trace") || hasDebugFlag("1");
- disabled = !value;
- enabled = value;
- return value;
- }
-}
-
-bool hasDebugFlag(const char *flag)
-{
- if (strchr(flag, ',') != NULL) {
- trace("INTERNAL ERROR: hasDebugFlag flag has comma: '%s'", flag);
- abort();
- }
- const char *const configCStr = getDebugConfig();
- if (configCStr[0] == '\0') {
- return false;
- }
- PreserveLastError preserve;
- std::string config(configCStr);
- std::string flagStr(flag);
- config = "," + config + ",";
- flagStr = "," + flagStr + ",";
- return config.find(flagStr) != std::string::npos;
-}
-
-void trace(const char *format, ...)
-{
- if (!isTracingEnabled())
- return;
-
- PreserveLastError preserve;
- char message[1024];
-
- va_list ap;
- va_start(ap, format);
- winpty_vsnprintf(message, format, ap);
- message[sizeof(message) - 1] = '\0';
- va_end(ap);
-
- const int currentTime = (int)(unixTimeMillis() % (100000 * 1000));
-
- char moduleName[1024];
- moduleName[0] = '\0';
- GetModuleFileNameA(NULL, moduleName, sizeof(moduleName));
- const char *baseName = strrchr(moduleName, '\\');
- baseName = (baseName != NULL) ? baseName + 1 : moduleName;
-
- char fullMessage[1024];
- winpty_snprintf(fullMessage,
- "[%05d.%03d %s,p%04d,t%04d]: %s",
- currentTime / 1000, currentTime % 1000,
- baseName, (int)GetCurrentProcessId(), (int)GetCurrentThreadId(),
- message);
- fullMessage[sizeof(fullMessage) - 1] = '\0';
-
- sendToDebugServer(fullMessage);
-}