[groff] 15/17: m4/groff.m4 (GROFF_PAGE): Remove awk dependency.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 1db8c0c1d2284be221635817f09878dd005cbfe1
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Sat Jul 23 06:14:55 2022 -0500

    m4/groff.m4 (GROFF_PAGE): Remove awk dependency.
    
    * m4/groff.m4 (GROFF_PAGE): Macro used awk(1) without `AC_REQUIRE`-ing a
      relevant macro or checking for its existence.  Fortunately, sed is
      powerful enough for our needs.  Remove dependency on awk.  Cope with
      "search" directive in resolv.conf having multiple arguments.  Match
      "domain" directive in same file instead of "dom", which I cannot find
      attested (this logic dates to 1991).  Rename `dom` shell variable to
      `domains` for clarity, since its multiplicity could be greater than 1.
---
 ChangeLog   | 11 +++++++++++
 m4/groff.m4 | 40 ++++++++++++++++++++++++----------------
 2 files changed, 35 insertions(+), 16 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 51c3fbae..be438bce 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2022-07-22  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       * m4/groff.m4 (GROFF_PAGE): Macro used awk(1) without
+       `AC_REQUIRE`-ing a relevant macro or checking for its existence.
+       Fortunately, sed is powerful enough for our needs.  Remove
+       dependency on awk.  Cope with "search" directive in resolv.conf
+       having multiple arguments.  Match "domain" directive in same
+       file instead of "dom", which I cannot find attested (this logic
+       dates to 1991).  Rename `dom` shell variable to `domains` for
+       clarity, since its multiplicity could be greater than 1.
+
 2022-07-22  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        * m4/groff.m4 (GROFF_PAGE): Refactor: drop AC_DEFINE of
diff --git a/m4/groff.m4 b/m4/groff.m4
index 838a152d..9d5f3b57 100644
--- a/m4/groff.m4
+++ b/m4/groff.m4
@@ -862,7 +862,8 @@ AC_DEFUN([GROFF_PAGE],
    groff_prefix=$prefix
    test "$prefix" = NONE && groff_prefix=$ac_default_prefix
    if test -z "$PAGE" && test -r /etc/papersize; then
-     PAGE=`cat /etc/papersize | sed -e 's/^[ ]*#.*//g' | tr -d "\n" | awk '{ 
print $1 }'`
+     sedexpr='s/#.*//;s/[ \t]\+/ /;s/ \+$//;s/^ \+//;/^$/d;p'
+     PAGE=`sed -n "$sedexpr" /etc/papersize`
    fi
    if test -z "$PAGE"; then
      descfile=
@@ -889,23 +890,30 @@ AC_DEFUN([GROFF_PAGE],
    fi
 
    if test -z "$PAGE"; then
-     dom=`awk '([$]1 == "dom" || [$]1 == "search") { print [$]2; exit}' \
-        /etc/resolv.conf 2>/dev/null`
-     if test -z "$dom"; then
-       dom=`(domainname) 2>/dev/null | tr -d '+'`
-       if test -z "$dom" \
-         || test "$dom" = '(none)'; then
-        dom=`(hostname) 2>/dev/null | grep '\.'`
+     domains=
+     if test -r /etc/resolv.conf; then
+       sedexpr='s/#.*//;s/[ \t]\+/ /;s/ \+$//;s/^ \+//;/^$/d;
+/^\(domain\|search\)/!d;s/\(domain\|search\) //;p'
+       domains=`sed -n "$sedexpr" /etc/resolv.conf`
+     fi
+     if test -z "$domains"; then
+       domains=`(domainname) 2>/dev/null | tr -d '+'`
+       if test -z "$domains" \
+         || test "$domains" = '(none)'; then
+        domains=`(hostname) 2>/dev/null | grep '\.'`
        fi
      fi
-     # If the top-level domain is two letters and it's not 'us' or 'ca'
-     # then they probably use A4 paper.
-     case "$dom" in
-     [*.[Uu][Ss]|*.[Cc][Aa])]
-       ;;
-     [*.[A-Za-z][A-Za-z])]
-       PAGE=A4 ;;
-     esac
+     # resolv.conf's "search" directive might return multiple domains.
+     # If any top-level domain is two letters and it's not 'us' or 'ca',
+     # assume the system uses A4 paper.
+     for d in $domains; do
+       case "$d" in
+       [*.[Uu][Ss]|*.[Cc][Aa])]
+        ;;
+       [*.[A-Za-z][A-Za-z])]
+        PAGE=A4 ;;
+       esac
+     done
    fi
 
    test -n "$PAGE" || PAGE=letter