xref: /netbsd-src/distrib/sets/join.awk (revision e9ed3c66a2362edb895fa40eb9ccc26c3599e88a)
1#	$NetBSD: join.awk,v 1.7 2019/10/24 16:52:11 rhialto Exp $
2#
3# Copyright (c) 2002 The NetBSD Foundation, Inc.
4# All rights reserved.
5#
6# This code is derived from software contributed to The NetBSD Foundation
7# by Luke Mewburn of Wasabi Systems.
8#
9# Redistribution and use in source and binary forms, with or without
10# modification, are permitted provided that the following conditions
11# are met:
12# 1. Redistributions of source code must retain the above copyright
13#    notice, this list of conditions and the following disclaimer.
14# 2. Redistributions in binary form must reproduce the above copyright
15#    notice, this list of conditions and the following disclaimer in the
16#    documentation and/or other materials provided with the distribution.
17#
18# THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21# PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28# POSSIBILITY OF SUCH DAMAGE.
29#
30# join.awk F1 F2
31#	Similar to join(1), this reads a list of words from F1
32#	and outputs lines in F2 with a first word that is in F1.
33#	For purposes of matching the first word, both instances are
34#	canonicalised via unvis(word); the version from F2 is printed.
35#	Neither file needs to be sorted.
36
37function unvis(s) \
38{
39	# XXX: We don't handle the complete range of vis encodings
40	unvis_result = ""
41	while (length(s) > 0) {
42		unvis_pos = match(s, "\\\\.")
43		if (unvis_pos == 0) {
44			unvis_result = unvis_result "" s
45			s = ""
46			break
47		}
48		# copy the part before the next backslash
49		unvis_result = unvis_result "" substr(s, 1, unvis_pos - 1)
50		s = substr(s, unvis_pos)
51		# process the backslash and next few chars
52		if (substr(s, 1, 2) == "\\\\") {
53			# double backslash -> single backslash
54			unvis_result = unvis_result "\\"
55			s = substr(s, 3)
56		} else if (match(s, "\\\\[0-7][0-7][0-7]") == 1) {
57			# \ooo with three octal digits.
58			# XXX: use strnum() is that is available
59			unvis_result = unvis_result "" sprintf("%c", \
60				0+substr(s, 2, 1) * 64 + \
61				0+substr(s, 3, 1) * 8 + \
62				0+substr(s, 4, 1))
63			s = substr(s, 5)
64		} else {
65			# unrecognised escape: keep the literal backslash
66			printf "%s: %s:%s: unrecognised escape %s\n", \
67				ARGV[0], (FILENAME ? FILENAME : "stdin"), FNR, \
68				substr(s, 1, 2) \
69				>"/dev/stderr"
70			unvis_result = unvis_result "" substr(s, 1, 1)
71			s = substr(s, 2)
72		}
73	}
74	return unvis_result
75}
76
77BEGIN \
78{
79	if (ARGC != 3) {
80		printf("Usage: join file1 file2\n") >"/dev/stderr"
81		exit 1
82	}
83	while ( (getline < ARGV[1]) > 0) {
84		f1 = unvis($1)
85		words[f1] = $0
86	}
87	delete ARGV[1]
88}
89
90{ f1 = unvis($1) }
91
92f1 in words \
93{
94	$1=""
95	print words[f1] $0
96}
97