cpython/Lib/tty.py
Soumendra Ganguly 486bc8e030
gh-85984: New additions and improvements to the tty library. (#101832)
New additions to the tty library. Functions added: cfmakeraw(), and cfmakecbreak(). The
functions setcbreak() and setraw() now return original termios to save an extra tcgetattr() call.

---------

Signed-off-by: Soumendra Ganguly <soumendraganguly@gmail.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Gregory P. Smith [Google LLC] <greg@krypto.org>
2023-05-19 18:13:30 +00:00

75 lines
2.0 KiB
Python

"""Terminal utilities."""
# Author: Steen Lumholt.
from termios import *
__all__ = ["cfmakeraw", "cfmakecbreak", "setraw", "setcbreak"]
# Indices for termios list.
IFLAG = 0
OFLAG = 1
CFLAG = 2
LFLAG = 3
ISPEED = 4
OSPEED = 5
CC = 6
def cfmakeraw(mode):
"""Make termios mode raw."""
# Clear all POSIX.1-2017 input mode flags.
# See chapter 11 "General Terminal Interface"
# of POSIX.1-2017 Base Definitions.
mode[IFLAG] &= ~(IGNBRK | BRKINT | IGNPAR | PARMRK | INPCK | ISTRIP |
INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF)
# Do not post-process output.
mode[OFLAG] &= ~OPOST
# Disable parity generation and detection; clear character size mask;
# let character size be 8 bits.
mode[CFLAG] &= ~(PARENB | CSIZE)
mode[CFLAG] |= CS8
# Clear all POSIX.1-2017 local mode flags.
mode[LFLAG] &= ~(ECHO | ECHOE | ECHOK | ECHONL | ICANON |
IEXTEN | ISIG | NOFLSH | TOSTOP)
# POSIX.1-2017, 11.1.7 Non-Canonical Mode Input Processing,
# Case B: MIN>0, TIME=0
# A pending read shall block until MIN (here 1) bytes are received,
# or a signal is received.
mode[CC][VMIN] = 1
mode[CC][VTIME] = 0
def cfmakecbreak(mode):
"""Make termios mode cbreak."""
# Do not map CR to NL on input.
mode[IFLAG] &= ~(ICRNL)
# Do not echo characters; disable canonical input.
mode[LFLAG] &= ~(ECHO | ICANON)
# POSIX.1-2017, 11.1.7 Non-Canonical Mode Input Processing,
# Case B: MIN>0, TIME=0
# A pending read shall block until MIN (here 1) bytes are received,
# or a signal is received.
mode[CC][VMIN] = 1
mode[CC][VTIME] = 0
def setraw(fd, when=TCSAFLUSH):
"""Put terminal into raw mode."""
mode = tcgetattr(fd)
new = list(mode)
cfmakeraw(new)
tcsetattr(fd, when, new)
return mode
def setcbreak(fd, when=TCSAFLUSH):
"""Put terminal into cbreak mode."""
mode = tcgetattr(fd)
new = list(mode)
cfmakecbreak(new)
tcsetattr(fd, when, new)
return mode