maint: use C locale more often

* gzexe.in, zdiff.in, zgrep.in:
Run expr and sed in the C locale when it might help to avoid
undefined behavior on non-GNU platforms.
* sample/zfile, znew.in: Run in the C locale, for simplicity and
to avoid undefined behavior on non-GNU platforms.

5 files changed, 27 insertions, 16 deletions

diff --git a/gzexe.in b/gzexe.in
index 1a691e0..5fc7204 100644
--- a/gzexe.in
+++ b/gzexe.in
@@ -91,7 +91,7 @@ for i do
     continue
   fi
   if test $decomp -eq 0; then
-    case `sed -n -e 1d -e '/^skip=[0-9][0-9]*$/p' -e 2q "$file"` in
+    case `LC_ALL=C sed -n -e 1d -e '/^skip=[0-9][0-9]*$/p' -e 2q "$file"` in
     skip=[0-9] | skip=[0-9][0-9] | skip=[0-9][0-9][0-9])
       printf >&2 '%s\n' "$0: $i is already gzexe'd"
       continue;;
@@ -203,7 +203,7 @@ EOF
   else
     # decompression
     skip=44
-    skip_line=`sed -e 1d -e 2q "$file"`
+    skip_line=`LC_ALL=C sed -e 1d -e 2q "$file"`
     case $skip_line in
     skip=[0-9] | skip=[0-9][0-9] | skip=[0-9][0-9][0-9])
       eval "$skip_line";;
diff --git a/sample/zfile b/sample/zfile
index 6b4514c..d6e7a59 100755
--- a/sample/zfile
+++ b/sample/zfile
@@ -1,5 +1,8 @@
 #!/bin/sh
 
+LC_ALL=C
+export LC_ALL
+
 if test $# = 0; then
   echo 'zfile: file(1) for programs which may be compressed with gzexe'
   echo usage: `basename $0`  files...
diff --git a/zdiff.in b/zdiff.in
index 012024e..eb4752b 100644
--- a/zdiff.in
+++ b/zdiff.in
@@ -59,7 +59,7 @@ do
   --h*) printf '%s\n' "$usage"   || exit 2; exit;;
   --v*) printf '%s\n' "$version" || exit 2; exit;;
   --) filesonly=t;;
-  -*\'*) cmp="$cmp '"`printf '%sX\n' "$arg" | sed "$escape"`;;
+  -*\'*) cmp="$cmp '"`printf '%sX\n' "$arg" | LC_ALL=C sed "$escape"`;;
   -[CDFISUWXx]) needop="'$arg'";;
   -?*) cmp="$cmp '$arg'";;
   *) case $needop in
@@ -103,7 +103,7 @@ case $file2 in
 '')
   case $file1 in
   *[-.]gz* | *[-.][zZ] | *.t[ga]z)
-    FILE=`expr "X$file1" : 'X\(.*\)[-.][zZtga]*$'`
+    FILE=`LC_ALL=C expr "X$file1" : 'X\(.*\)[-.][zZtga]*$'`
     gzip_status=$(
       exec 4>&1
       ('gzip' -cd -- "$file1" 4>&-; echo $? >&4) 3>&- |
diff --git a/zgrep.in b/zgrep.in
index 6a16dd1..2cb2426 100644
--- a/zgrep.in
+++ b/zgrep.in
@@ -64,30 +64,33 @@ while test $# -ne 0; do
 
   case $option in
   (-[0123456789EFGHIKLPRTUVZabchilnoqrsuvwxyz]*[!0123456789]*)
-    arg2=-\'$(expr "X$option" : 'X-.[0-9]*\(.*\)' | sed "$escape")
+    arg2=-\'$(LC_ALL=C expr "X$option" : 'X-.[0-9]*\(.*\)' |
+                LC_ALL=C sed "$escape")
     eval "set -- $arg2 "'${1+"$@"}'
-    option=$(expr "X$option" : 'X\(-.[0-9]*\)');;
+    option=$(LC_ALL=C expr "X$option" : 'X\(-.[0-9]*\)');;
   (--binary-*=* | --[lm]a*=* | --reg*=*)
     ;;
   (-[ABCDXdefm] | --binary-* | --file | --[lm]a* | --reg*)
     case ${1?"$option option requires an argument"} in
     (*\'*)
-      optarg=" '"$(printf '%s\n' "$1" | sed "$escape");;
+      optarg=" '"$(printf '%s\n' "$1" | LC_ALL=C sed "$escape");;
     (*)
       optarg=" '$1'";;
     esac
     shift;;
   (-f?*\'*)
-    optarg=" '"$(expr "X$option" : 'X-f\(.*\)' | sed "$escape")
+    optarg=" '"$(LC_ALL=C expr "X$option" : 'X-f\(.*\)' |
+                   LC_ALL=C sed "$escape")
     option=-f;;
   (-f?*)
-    optarg=" '"$(expr "X$option" : 'X-f\(.*\)')\'
+    optarg=" '"$(LC_ALL=C expr "X$option" : 'X-f\(.*\)')\'
     option=-f;;
   (--file=*\'*)
-    optarg=" '"$(expr "X$option" : 'X--file=\(.*\)' | sed "$escape")
+    optarg=" '"$(LC_ALL=C expr "X$option" : 'X--file=\(.*\)' |
+                   LC_ALL=C sed "$escape")
     option=--file;;
   (--file=*)
-    optarg=" '"$(expr "X$option" : 'X--file=\(.*\)')\'
+    optarg=" '"$(LC_ALL=C expr "X$option" : 'X--file=\(.*\)')\'
     option=--file;;
   (--)
     break;;
@@ -96,7 +99,8 @@ while test $# -ne 0; do
   (*)
     case $option in
     (*\'*)
-      operands="$operands '"$(printf '%s\n' "$option" | sed "$escape");;
+      operands="$operands '"$(printf '%s\n' "$option" | LC_ALL=C sed "$escape")
+      ;;
     (*)
       operands="$operands '$option'";;
     esac
@@ -169,7 +173,7 @@ while test $# -ne 0; do
 
   case $option in
   (*\'?*)
-    option=\'$(printf '%s\n' "$option" | sed "$escape");;
+    option=\'$(printf '%s\n' "$option" | LC_ALL=C sed "$escape");;
   (*)
     option="'$option'";;
   esac
@@ -182,7 +186,7 @@ eval "set -- $operands "'${1+"$@"}'
 if test $have_pat -eq 0; then
   case ${1?"missing pattern; try \`$0 --help' for help"} in
   (*\'*)
-    grep="$grep -- '"$(printf '%s\n' "$1" | sed "$escape");;
+    grep="$grep -- '"$(printf '%s\n' "$1" | LC_ALL=C sed "$escape");;
   (*)
     grep="$grep -- '$1'";;
   esac
@@ -221,7 +225,7 @@ do
       (*'
 '* | *'&'* | *'\'* | *'|'*)
           icolon=$(printf '%s\n' "$i:" |
-                     sed -e 's/[&\|]/\\&/g' -e '$!s/$/\\/');;
+                     LC_ALL=C sed -e 's/[&\|]/\\&/g' -e '$!s/$/\\/');;
       (*) icolon="$i:";;
       esac
       sed_script="s|^|$icolon|"
@@ -229,7 +233,8 @@ do
       # Fail if grep or sed fails.
       r=$(
         exec 4>&1
-        (eval "$grep" 4>&-; echo $? >&4) 3>&- | sed "$sed_script" >&3 4>&-
+        (eval "$grep" 4>&-; echo $? >&4) 3>&- |
+           LC_ALL=C sed "$sed_script" >&3 4>&-
       ) || { r=$?; test $r -lt 2 && r=2; }
       test 256 -le $r && r=$(expr 128 + $r % 128)
       exit $r
diff --git a/znew.in b/znew.in
index 45d0764..ea76a22 100644
--- a/znew.in
+++ b/znew.in
@@ -18,6 +18,9 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+LC_ALL=C
+export LC_ALL
+
 version="znew (gzip) @VERSION@
 Copyright (C) 2010-2018 Free Software Foundation, Inc.
 This is free software.  You may redistribute copies of it under the terms of