70 lines
1.7 KiB
Python
70 lines
1.7 KiB
Python
#!/usr/bin/env python3
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# Copyright 2019 The Chromium OS Authors. All rights reserved.
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# Use of this source code is governed by a BSD-style license that can be
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# found in the LICENSE file.
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import sys
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def chargen(modulo, max_chars):
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"""Generate a stream of characters on the console.
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The stream is an ever incrementing pattern of characters from the
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following set: 0..9A..Za..z.
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Args:
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modulo: an int, restart the pattern every modulo characters, if
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modulo is non zero
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max_chars: an int, stop printing after this number of characters if non
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zero, if zero - print indefinitely
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"""
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base = '0'
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c = base
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counter = 0
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while True:
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sys.stdout.write(c)
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counter = counter + 1
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if (max_chars != 0) and (counter == max_chars):
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sys.stdout.write('\n')
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return
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if modulo and ((counter % modulo) == 0):
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c = base
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continue
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if c == 'z':
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c = base
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elif c == 'Z':
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c = 'a'
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elif c == '9':
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c = 'A'
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else:
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c = '%c' % (ord(c) + 1)
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def main(args):
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'''Process command line arguments and invoke chargen if args are valid'''
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modulo = 0
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max_chars = 0
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try:
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if len(args) > 0:
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modulo = int(args[0])
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if len(args) > 1:
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max_chars = int(args[1])
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except ValueError:
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sys.stderr.write('usage %s:'
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"['seq_length' ['max_chars']]\n")
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sys.exit(1)
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try:
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chargen(modulo, max_chars)
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except KeyboardInterrupt:
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print()
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if __name__ == '__main__':
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main(sys.argv[1:])
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sys.exit(0)
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