Module Name: src
Committed By: apb
Date: Thu Oct 23 14:19:33 UTC 2014
Modified Files:
src/distrib/sets: join.awk
Log Message:
Add vis() function, and canonicalise file names via vis(unvis($1)).
XXX: The vis() function is very limited, due to the absence of ord()
in NetBSD's awk.
To generate a diff of this commit:
cvs rdiff -u -r1.4 -r1.5 src/distrib/sets/join.awk
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/distrib/sets/join.awk
diff -u src/distrib/sets/join.awk:1.4 src/distrib/sets/join.awk:1.5
--- src/distrib/sets/join.awk:1.4 Tue Oct 21 23:15:38 2014
+++ src/distrib/sets/join.awk Thu Oct 23 14:19:33 2014
@@ -1,4 +1,4 @@
-# $NetBSD: join.awk,v 1.4 2014/10/21 23:15:38 apb Exp $
+# $NetBSD: join.awk,v 1.5 2014/10/23 14:19:33 apb Exp $
#
# Copyright (c) 2002 The NetBSD Foundation, Inc.
# All rights reserved.
@@ -30,7 +30,8 @@
# join.awk F1 F2
# Similar to join(1), this reads a list of words from F1
# and outputs lines in F2 with a first word that is in F1.
-# Neither file needs to be sorted
+# The first word is canonicalised via vis(unvis(word))).
+# Neither file needs to be sorted.
function unvis(s) \
{
@@ -53,7 +54,7 @@ function unvis(s) \
s = substr(s, 3)
} else if (match(s, "\\\\[0-7][0-7][0-7]") == 1) {
# \ooo with three octal digits.
- # XXX: use strnum() is that is available
+ # XXX: use strtonum() when that is available
unvis_result = unvis_result "" sprintf("%c", \
0+substr(s, 2, 1) * 64 + \
0+substr(s, 3, 1) * 8 + \
@@ -72,6 +73,60 @@ function unvis(s) \
return unvis_result
}
+function vis(s) \
+{
+ # We need to encode backslash, space, and tab, because they
+ # would interfere with scripts that attempt to manipulate
+ # the set files.
+ #
+ # We make no attempt to encode shell special characters
+ # such as " ' $ ( ) { } [ ] < > * ?, because nothing that
+ # parses set files would need that.
+ #
+ # We would like to handle other white space or non-graph
+ # characters, because they may be confusing for human readers,
+ # but they are too difficult to handle in awk without the ord()
+ # function, so we print an error message.
+ #
+ # As of October 2014, no files in the set lists contain
+ # characters that would need any kind of encoding.
+ #
+ vis_result = ""
+ while (length(s) > 0) {
+ vis_pos = match(s, "(\\\\|[[:space:]]|[^[:graph:]])")
+ if (vis_pos == 0) {
+ vis_result = vis_result "" s
+ s = ""
+ break
+ }
+ # copy the part before the next special char
+ vis_result = vis_result "" substr(s, 1, vis_pos - 1)
+ vis_char = substr(s, vis_pos, 1)
+ s = substr(s, vis_pos + 1)
+ # process the special char
+ if (vis_char == "\\") {
+ # backslash -> double backslash
+ vis_result = vis_result "\\\\"
+ } else if (vis_char == " ") {
+ # space -> \040
+ vis_result = vis_result "\\040"
+ } else if (vis_char == "\t") {
+ # tab -> \011
+ vis_result = vis_result "\\011"
+ } else {
+ # generalised \ooo with three octal digits.
+ # XXX: I don't know how to do this in awk without ord()
+ printf "%s: %s:%s: cannot perform vis encoding\n", \
+ ARGV[0], (FILENAME ? FILENAME : "stdin"), FNR \
+ >"/dev/stderr"
+ vis_result = vis_result "" vis_char
+ }
+ }
+ return vis_result
+}
+
+// { $1 = vis(unvis($1)); print }
+
BEGIN \
{
if (ARGC != 3) {
@@ -79,13 +134,13 @@ BEGIN \
exit 1
}
while ( (getline < ARGV[1]) > 0) {
- $1 = unvis($1)
+ $1 = vis(unvis($1))
words[$1] = $0
}
delete ARGV[1]
}
-// { $1 = unvis($1) }
+// { $1 = vis(unvis($1)) }
$1 in words \
{
