8
from script_commands import (
16
"""Run a tc command under sudo.
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:param tc: The remainder of the command (leaving out tc).
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subprocess.call('sudo tc ' + command, shell=True)
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@helps(delay='Length of delay in miliseconds (each way).',
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port='Port to induce delay on.')
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def start(delay=500, port=443):
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"""Add artificial latency to the lo interface on the specified port."""
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tc('qdisc add dev lo root handle 1: prio')
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tc('qdisc add dev lo parent 1:3 handle 30: netem delay %dms' % delay)
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tc('filter add dev lo protocol ip parent 1:0 prio 3 u32 match ip'
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' dport %d 0xffff flowid 1:3' % port)
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tc('filter add dev lo protocol ip parent 1:0 prio 3 u32 match ip'
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' sport %d 0xffff flowid 1:3' % port)
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"""Remove latency from the lo."""
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tc('qdisc del dev lo root')
47
if __name__ == "__main__":
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run_subcommand(subcommands, sys.argv[1:])
50
except UserError as e:
51
sys.stderr.write(str(e)+'\n')