AuroraMiddleware/winpty
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Windows 10 new console: try to avoid freezing the console while scraping

Browse Source 
Fixes https://github.com/rprichard/winpty/issues/53
This commit is contained in:
Ryan Prichard 2016-06-09 02:34:17 -05:00
parent b8c2c41eb7
commit fa6ba9c725
5 changed files with 170 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

62
misc/FreezePerfTest.cc Normal file
View File

@ -0,0 +1,62 @@
#include <windows.h>
#include "TestUtil.cc"
const int SC_CONSOLE_MARK = 0xFFF2;
const int SC_CONSOLE_SELECT_ALL = 0xFFF5;
int main(int argc, char *argv[0]) {
if (argc != 2) {
printf("Usage: %s (mark|selectall|read)\n", argv[0]);
return 1;
}
enum class Test { Mark, SelectAll, Read } test;
if (!strcmp(argv[1], "mark")) {
test = Test::Mark;
} else if (!strcmp(argv[1], "selectall")) {
test = Test::SelectAll;
} else if (!strcmp(argv[1], "read")) {
test = Test::Read;
} else {
printf("Invalid test: %s\n", argv[1]);
return 1;
}
HANDLE conout = GetStdHandle(STD_OUTPUT_HANDLE);
TimeMeasurement tm;
HWND hwnd = GetConsoleWindow();
setWindowPos(0, 0, 1, 1);
setBufferSize(100, 3000);
system("cls");
setWindowPos(0, 2975, 100, 25);
setCursorPos(0, 2999);
ShowWindow(hwnd, SW_HIDE);
for (int i = 0; i < 1000; ++i) {
// CONSOLE_SCREEN_BUFFER_INFO info = {};
// GetConsoleScreenBufferInfo(conout, &info);
if (test == Test::Mark) {
SendMessage(hwnd, WM_SYSCOMMAND, SC_CONSOLE_MARK, 0);
SendMessage(hwnd, WM_CHAR, 27, 0x00010001);
} else if (test == Test::SelectAll) {
SendMessage(hwnd, WM_SYSCOMMAND, SC_CONSOLE_SELECT_ALL, 0);
SendMessage(hwnd, WM_CHAR, 27, 0x00010001);
} else if (test == Test::Read) {
static CHAR_INFO buffer[100 * 3000];
const SMALL_RECT readRegion = {0, 0, 99, 2999};
SMALL_RECT tmp = readRegion;
BOOL ret = ReadConsoleOutput(conout, buffer, {100, 3000}, {0, 0}, &tmp);
ASSERT(ret && !memcmp(&tmp, &readRegion, sizeof(tmp)));
}
}
ShowWindow(hwnd, SW_SHOW);
printf("elapsed: %f\n", tm.elapsed());
return 0;
}

27
misc/WindowsBugCrashReader.cc Normal file
View File

@ -0,0 +1,27 @@
// I noticed this on the ConEmu web site:
//
// https://social.msdn.microsoft.com/Forums/en-US/40c8e395-cca9-45c8-b9b8-2fbe6782ac2b/readconsoleoutput-cause-access-violation-writing-location-exception
// https://conemu.github.io/en/MicrosoftBugs.html
//
// In Windows 7, 8, and 8.1, a ReadConsoleOutputW with an out-of-bounds read
// region crashes the application. I have reproduced the problem on Windows 8
// and 8.1, but not on Windows 7.
//
#include <windows.h>
#include "TestUtil.cc"
int main() {
setWindowPos(0, 0, 1, 1);
setBufferSize(80, 25);
setWindowPos(0, 0, 80, 25);
const HANDLE conout = openConout();
static CHAR_INFO lineBuf[80];
SMALL_RECT readRegion = { 0, 999, 79, 999 };
const BOOL ret = ReadConsoleOutputW(conout, lineBuf, {80, 1}, {0, 0}, &readRegion);
ASSERT(!ret && "ReadConsoleOutputW should have failed");
return 0;
}

4
src/agent/Agent.cc
View File

@ -524,7 +524,7 @@ void Agent::resizeWindow(const int cols, const int rows)
trace("resizeWindow: invalid size: cols=%d,rows=%d", cols, rows);
return;
}
Win32Console::FreezeGuard guard(m_console, true);
Win32Console::FreezeGuard guard(m_console, m_console.frozen());
const Coord newSize(cols, rows);
ConsoleScreenBufferInfo info;
m_primaryScraper->resizeWindow(*openPrimaryBuffer(), newSize, info);
@ -536,7 +536,7 @@ void Agent::resizeWindow(const int cols, const int rows)
void Agent::scrapeBuffers()
{
Win32Console::FreezeGuard guard(m_console, true);
Win32Console::FreezeGuard guard(m_console, m_console.frozen());
ConsoleScreenBufferInfo info;
m_primaryScraper->scrapeBuffer(*openPrimaryBuffer(), info);
m_consoleInput->setMouseWindowRect(info.windowRect());

89
src/agent/Scraper.cc
View File

@ -93,6 +93,7 @@ Scraper::~Scraper()
{
}
// Whether or not the agent is frozen on entry, it will be frozen on exit.
void Scraper::resizeWindow(Win32ConsoleBuffer &buffer,
Coord newSize,
ConsoleScreenBufferInfo &finalInfoOut)
@ -103,6 +104,7 @@ void Scraper::resizeWindow(Win32ConsoleBuffer &buffer,
m_consoleBuffer = nullptr;
}
// This function may freeze the agent, but it will not unfreeze it.
void Scraper::scrapeBuffer(Win32ConsoleBuffer &buffer,
ConsoleScreenBufferInfo &finalInfoOut)
{
@ -310,7 +312,18 @@ void Scraper::syncConsoleContentAndSize(
bool forceResize,
ConsoleScreenBufferInfo &finalInfoOut)
{
Win32Console::FreezeGuard guard(m_console, true);
// We'll try to avoid freezing the console by reading large chunks (or
// all!) of the screen buffer without otherwise attempting to synchronize
// with the console application. We can only do this on Windows 10 and up
// because:
// - Prior to Windows 8, the size of a ReadConsoleOutputW call was limited
// by the ~32KB RPC buffer.
// - Prior to Windows 10, an out-of-range read region crashes the caller.
// (See misc/WindowsBugCrashReader.cc.)
//
if (!m_console.isNewW10() || forceResize) {
m_console.setFrozen(true);
}
const ConsoleScreenBufferInfo info = m_consoleBuffer->bufferInfo();
BOOL cursorVisible = true;
@ -332,6 +345,7 @@ void Scraper::syncConsoleContentAndSize(
// When we switch from direct->scrolling mode, make sure the console is
// the right size.
if (!m_directMode) {
m_console.setFrozen(true);
forceResize = true;
}
}
@ -339,7 +353,14 @@ void Scraper::syncConsoleContentAndSize(
if (m_directMode) {
directScrapeOutput(info, cursorVisible);
} else {
scrollingScrapeOutput(info, cursorVisible);
if (!m_console.frozen()) {
if (!scrollingScrapeOutput(info, cursorVisible, true)) {
m_console.setFrozen(true);
}
}
if (m_console.frozen()) {
scrollingScrapeOutput(info, cursorVisible, false);
}
}
if (forceResize) {
@ -397,8 +418,9 @@ void Scraper::directScrapeOutput(const ConsoleScreenBufferInfo &info,
}
}
void Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
bool cursorVisible)
bool Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
bool cursorVisible,
bool tentative)
{
const Coord cursor = info.cursorPosition();
const SmallRect windowRect = info.windowRect();
@ -406,8 +428,13 @@ void Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
if (m_syncRow != -1) {
// If a synchronizing marker was placed into the history, look for it
// and adjust the scroll count.
int markerRow = findSyncMarker();
const int markerRow = findSyncMarker();
if (markerRow == -1) {
if (tentative) {
// I *think* it's possible to keep going, but it's simple to
// bail out.
return false;
}
// Something has happened. Reset the terminal.
trace("Sync marker has disappeared -- resetting the terminal"
" (m_syncCounter=%u)",
@ -422,6 +449,17 @@ void Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
}
}
// Creating a new sync row requires clearing part of the console buffer, so
// avoid doing it if there's already a sync row that's good enough.
// TODO: replace hard-coded constants
const int newSyncRow = static_cast<int>(windowRect.top()) - 200;
const bool shouldCreateSyncRow = newSyncRow >= m_syncRow + 200;
if (tentative && shouldCreateSyncRow) {
// It's difficult even in principle to put down a new marker if the
// console can scroll an arbitrarily amount while we're writing.
return false;
}
// Update the dirty line count:
// - If the window has moved, the entire window is dirty.
// - Everything up to the cursor is dirty.
@ -432,6 +470,11 @@ void Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
// The window has moved down, presumably as a result of scrolling.
markEntireWindowDirty(windowRect);
} else if (windowRect.top() < m_dirtyWindowTop) {
if (tentative) {
// I *think* it's possible to keep going, but it's simple to
// bail out.
return false;
}
// The window has moved upward. This is generally not expected to
// happen, but the CMD/PowerShell CLS command will move the window
// to the top as part of clearing everything else in the console.
@ -470,6 +513,32 @@ void Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
MAX_CONSOLE_WIDTH),
stopReadLine - firstReadLine));
// If we're scraping the buffer without freezing it, we have to query the
// buffer position data separately from the buffer content, so the two
// could easily be out-of-sync. If they *are* out-of-sync, abort the
// scrape operation and restart it frozen. (We may have updated the
// dirty-line high-water-mark, but that should be OK.)
if (tentative) {
const auto infoCheck = m_consoleBuffer->bufferInfo();
if (info.bufferSize() != infoCheck.bufferSize() ||
info.windowRect() != infoCheck.windowRect() ||
info.cursorPosition() != infoCheck.cursorPosition()) {
return false;
}
if (m_syncRow != -1 && m_syncRow != findSyncMarker()) {
return false;
}
}
if (shouldCreateSyncRow) {
ASSERT(!tentative);
createSyncMarker(newSyncRow);
}
// At this point, we're finished interacting (reading or writing) the
// console, and we just need to convert our collected data into terminal
// output.
scanForDirtyLines(windowRect);
// Note that it's possible for all the lines on the current window to
@ -511,17 +580,11 @@ void Scraper::scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
m_scrapedLineCount = windowRect.top() + m_scrolledCount;
// Creating a new sync row requires clearing part of the console buffer, so
// avoid doing it if there's already a sync row that's good enough.
// TODO: replace hard-coded constants
const int newSyncRow = static_cast<int>(windowRect.top()) - 200;
if (newSyncRow >= 1 && newSyncRow >= m_syncRow + 200) {
createSyncMarker(newSyncRow);
}
if (cursorVisible) {
m_terminal->showTerminalCursor(cursorColumn, cursorLine);
}
return true;
}
void Scraper::syncMarkerText(CHAR_INFO (&output)[SYNC_MARKER_LEN])

5
src/agent/Scraper.h
View File

@ -71,8 +71,9 @@ private:
ConsoleScreenBufferInfo &finalInfoOut);
void directScrapeOutput(const ConsoleScreenBufferInfo &info,
bool cursorVisible);
void scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
bool cursorVisible);
bool scrollingScrapeOutput(const ConsoleScreenBufferInfo &info,
bool cursorVisible,
bool tentative);
void syncMarkerText(CHAR_INFO (&output)[SYNC_MARKER_LEN]);
int findSyncMarker();
void createSyncMarker(int row);