diff options
Diffstat (limited to 'tools')
-rw-r--r-- | tools/display-fpathconf.py | 41 | ||||
-rw-r--r-- | tools/display-maxcanon.py | 80 |
2 files changed, 121 insertions, 0 deletions
diff --git a/tools/display-fpathconf.py b/tools/display-fpathconf.py new file mode 100644 index 0000000..d40cbae --- /dev/null +++ b/tools/display-fpathconf.py @@ -0,0 +1,41 @@ +#!/usr/bin/env python +"""Displays os.fpathconf values related to terminals. """ +from __future__ import print_function +import sys +import os + + +def display_fpathconf(): + DISP_VALUES = ( + ('PC_MAX_CANON', ('Max no. of bytes in a ' + 'terminal canonical input line.')), + ('PC_MAX_INPUT', ('Max no. of bytes for which ' + 'space is available in a terminal input queue.')), + ('PC_PIPE_BUF', ('Max no. of bytes which will ' + 'be written atomically to a pipe.')), + ('PC_VDISABLE', 'Terminal character disabling value.') + ) + FMT = '{name:<13} {value:<5} {description}' + + # column header + print(FMT.format(name='name', value='value', description='description')) + print(FMT.format(name=('-' * 13), value=('-' * 5), description=('-' * 11))) + + fd = sys.stdin.fileno() + for name, description in DISP_VALUES: + key = os.pathconf_names.get(name, None) + if key is None: + value = 'UNDEF' + else: + try: + value = os.fpathconf(fd, name) + except OSError as err: + value = 'OSErrno {0.errno}'.format(err) + if name == 'PC_VDISABLE': + value = hex(value) + print(FMT.format(name=name, value=value, description=description)) + print() + + +if __name__ == '__main__': + display_fpathconf() diff --git a/tools/display-maxcanon.py b/tools/display-maxcanon.py new file mode 100644 index 0000000..cbd664f --- /dev/null +++ b/tools/display-maxcanon.py @@ -0,0 +1,80 @@ +#!/usr/bin/env python +""" +This tool uses pexpect to test expected Canonical mode length. + +All systems use the value of MAX_CANON which can be found using +fpathconf(3) value PC_MAX_CANON -- with the exception of Linux +and FreeBSD. + +Linux, though defining a value of 255, actually honors the value +of 4096 from linux kernel include file tty.h definition +N_TTY_BUF_SIZE. + +Linux also does not honor IMAXBEL. termios(3) states, "Linux does not +implement this bit, and acts as if it is always set." Although these +tests ensure it is enabled, this is a non-op for Linux. + +FreeBSD supports neither, and instead uses a fraction (1/5) of the tty +speed which is always 9600. Therefor, the maximum limited input line +length is 9600 / 5 = 1920. + +These tests only ensure the correctness of the behavior described by +the sendline() docstring -- the values listed there, and above should +be equal to the output of the given OS described, but no promises! +""" +# std import +from __future__ import print_function +import sys +import os + + +def detect_maxcanon(): + import pexpect + bashrc = os.path.join( + # re-use pexpect/replwrap.py's bashrc file, + os.path.dirname(__file__), os.path.pardir, 'pexpect', 'bashrc.sh') + + child = pexpect.spawn('bash', ['--rcfile', bashrc], + echo=True, encoding='utf8', timeout=3) + + child.sendline(u'echo -n READY_; echo GO') + child.expect_exact(u'READY_GO') + + child.sendline(u'stty icanon imaxbel erase ^H; echo -n retval: $?') + child.expect_exact(u'retval: 0') + + child.sendline(u'echo -n GO_; echo AGAIN') + child.expect_exact(u'GO_AGAIN') + child.sendline(u'cat') + + child.delaybeforesend = 0 + + column, blocksize = 0, 64 + ch_marker = u'_' + + print('auto-detecting MAX_CANON: ', end='') + sys.stdout.flush() + + while True: + child.send(ch_marker * blocksize) + result = child.expect([ch_marker * blocksize, u'\a']) + if result == 0: + # entire block fit without emitting bel + column += blocksize + elif result == 1: + # an '\a' was emitted, count the number of ch_markers + # found since last blocksize, determining our MAX_CANON + column += child.before.count(ch_marker) + break + print(column) + +if __name__ == '__main__': + try: + detect_maxcanon() + except ImportError: + # we'd like to use this with CI -- but until we integrate + # with tox, we can't determine a period in testing when + # the pexpect module has been installed + print('warning: pexpect not in module path, MAX_CANON ' + 'could not be determined by systems test.', + file=sys.stderr) |