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Merged
tompng merged 2 commits into from
Dec 28, 2025
+49 −23
Merged

Duplicate console handles and use them #875

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5ca4c3b
duplicate console handle before use
YO4 Dec 9, 2025
bf2c176
Revert "Get console handle again and retry when Win32API call fails (…
YO4 Dec 9, 2025
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72 changes: 49 additions & 23 deletions lib/reline/io/windows.rb
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Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,42 @@ def initialize
@SetConsoleMode = Win32API.new('kernel32', 'SetConsoleMode', ['L', 'L'], 'L')
@WaitForSingleObject = Win32API.new('kernel32', 'WaitForSingleObject', ['L', 'L'], 'L')

# Win32API does not have pointer size integer.
# Current process pseudo handle (-1)LL seems to fail to be passed to DuplicateHandle.
# @GetCurrentProcess = Win32API.new('kernel32', 'GetCurrentProcess', [], 'L')
@GetCurrentProcessId = Win32API.new('kernel32', 'GetCurrentProcessId', [], 'L')
@OpenProcess = Win32API.new('kernel32', 'OpenProcess', ['L', 'L', 'L'], 'L')
@CloseHandle = Win32API.new('kernel32', 'CloseHandle', ['L'], 'L')
@DuplicateHandle = Win32API.new('kernel32', 'DuplicateHandle', ['L', 'L', 'L', 'P', 'I', 'I', 'I'], 'L')

current_process_handle = @OpenProcess.call(
0x0040, # PROCESS_DUP_HANDLE
0, # bInheritHandle
@GetCurrentProcessId.call()
)
duplicate_handle = proc { |handle|
dupHandle = "\0" * 8
@DuplicateHandle.call(
current_process_handle,
handle,
current_process_handle,
dupHandle,
0, # dwDesiredAccess
0, # bInheritHandle
2 # dwOptions = DUPLICATE_SAME_ACCESS
)
dupHandle.unpack1("J")
}
if (dup = duplicate_handle.call(@hConsoleHandle)) != 0
@hConsoleHandle = dup
at_exit { @CloseHandle.call(@hConsoleHandle) }
end
if (dup = duplicate_handle.call(@hConsoleInputHandle)) != 0
@hConsoleInputHandle = dup
at_exit { @CloseHandle.call(@hConsoleInputHandle) }
end
@CloseHandle.call(current_process_handle)

@legacy_console = getconsolemode & ENABLE_VIRTUAL_TERMINAL_PROCESSING == 0
end

Expand Down Expand Up @@ -162,24 +198,14 @@ def call(*args)
ENABLE_WRAP_AT_EOL_OUTPUT = 2
ENABLE_VIRTUAL_TERMINAL_PROCESSING = 4

# Calling Win32API with console handle is reported to fail after executing some external command.
# We need to refresh console handle and retry the call again.
private def call_with_console_handle(win32func, *args)
val = win32func.call(@hConsoleHandle, *args)
return val if val != 0

@hConsoleHandle = @GetStdHandle.call(STD_OUTPUT_HANDLE)
win32func.call(@hConsoleHandle, *args)
end

private def getconsolemode
mode = +"\0\0\0\0"
call_with_console_handle(@GetConsoleMode, mode)
@GetConsoleMode.call(@hConsoleHandle, mode)
mode.unpack1('L')
end

private def setconsolemode(mode)
call_with_console_handle(@SetConsoleMode, mode)
@SetConsoleMode.call(@hConsoleHandle, mode)
end

#if @legacy_console
Expand Down Expand Up @@ -355,7 +381,7 @@ def get_console_screen_buffer_info
# [18,2] dwMaximumWindowSize.X
# [20,2] dwMaximumWindowSize.Y
csbi = 0.chr * 22
if call_with_console_handle(@GetConsoleScreenBufferInfo, csbi) != 0
if @GetConsoleScreenBufferInfo.call(@hConsoleHandle, csbi) != 0
# returns [width, height, x, y, attributes, left, top, right, bottom]
csbi.unpack("s9")
else
Expand All @@ -377,7 +403,7 @@ def cursor_pos

def move_cursor_column(val)
_, _, _, y, = get_console_screen_buffer_info
call_with_console_handle(@SetConsoleCursorPosition, y * 65536 + val) if y
@SetConsoleCursorPosition.call(@hConsoleHandle, y * 65536 + val) if y
end

def move_cursor_up(val)
Expand All @@ -386,7 +412,7 @@ def move_cursor_up(val)
return unless y
y = (y - top) - val
y = 0 if y < 0
call_with_console_handle(@SetConsoleCursorPosition, (y + top) * 65536 + x)
@SetConsoleCursorPosition.call(@hConsoleHandle, (y + top) * 65536 + x)
elsif val < 0
move_cursor_down(-val)
end
Expand All @@ -399,7 +425,7 @@ def move_cursor_down(val)
screen_height = bottom - top
y = (y - top) + val
y = screen_height if y > screen_height
call_with_console_handle(@SetConsoleCursorPosition, (y + top) * 65536 + x)
@SetConsoleCursorPosition.call(@hConsoleHandle, (y + top) * 65536 + x)
elsif val < 0
move_cursor_up(-val)
end
Expand All @@ -409,8 +435,8 @@ def erase_after_cursor
width, _, x, y, attributes, = get_console_screen_buffer_info
return unless x
written = 0.chr * 4
call_with_console_handle(@FillConsoleOutputCharacter, 0x20, width - x, y * 65536 + x, written)
call_with_console_handle(@FillConsoleOutputAttribute, attributes, width - x, y * 65536 + x, written)
@FillConsoleOutputCharacter.call(@hConsoleHandle, 0x20, width - x, y * 65536 + x, written)
@FillConsoleOutputAttribute.call(@hConsoleHandle, attributes, width - x, y * 65536 + x, written)
end

# This only works when the cursor is at the bottom of the scroll range
Expand All @@ -428,9 +454,9 @@ def clear_screen
fill_length = width * (bottom - top + 1)
screen_topleft = top * 65536
written = 0.chr * 4
call_with_console_handle(@FillConsoleOutputCharacter, 0x20, fill_length, screen_topleft, written)
call_with_console_handle(@FillConsoleOutputAttribute, attributes, fill_length, screen_topleft, written)
call_with_console_handle(@SetConsoleCursorPosition, screen_topleft)
@FillConsoleOutputCharacter.call(@hConsoleHandle, 0x20, fill_length, screen_topleft, written)
@FillConsoleOutputAttribute.call(@hConsoleHandle, attributes, fill_length, screen_topleft, written)
@SetConsoleCursorPosition.call(@hConsoleHandle, screen_topleft)
else
@output.write "\e[2J" "\e[H"
end
Expand All @@ -444,14 +470,14 @@ def hide_cursor
size = 100
visible = 0 # 0 means false
cursor_info = [size, visible].pack('Li')
call_with_console_handle(@SetConsoleCursorInfo, cursor_info)
@SetConsoleCursorInfo.call(@hConsoleHandle, cursor_info)
end

def show_cursor
size = 100
visible = 1 # 1 means true
cursor_info = [size, visible].pack('Li')
call_with_console_handle(@SetConsoleCursorInfo, cursor_info)
@SetConsoleCursorInfo.call(@hConsoleHandle, cursor_info)
end

def set_winch_handler(&handler)
Expand Down