[PATCH] Fix "znew -K" to work without use of compress utility

[Dmitry V. Levin]

* znew.in: Change -K option to imply -t, do not use compress(1).
* znew.1: Document it.
* tests/znew-k: New test.
* Makefile.am (TESTS): Add it.
---
znew(1) can try to use compress(1) in certain circumstances, and it
fails to handle the case when this external utility is not available.
Proposed fix changes "znew -K" behaviour to imply -t option, so
znew(1) will no longer use compress(1).

 Makefile.am  |    3 ++-
 tests/znew-k |   42 ++++++++++++++++++++++++++++++++++++++++++
 znew.1       |    3 ++-
 znew.in      |    8 +++-----
 4 files changed, 49 insertions(+), 7 deletions(-)
 create mode 100755 tests/znew-k

diff --git a/Makefile.am b/Makefile.am
index ac95615..cea37f2 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -108,7 +108,8 @@ TESTS =                                             \
   tests/memcpy-abuse                           \
   tests/trailing-nul                           \
   tests/zdiff                                  \
-  tests/zgrep-f
+  tests/zgrep-f                                        \
+  tests/znew-k
 
 EXTRA_DIST += $(TESTS)
 
diff --git a/tests/znew-k b/tests/znew-k
new file mode 100755
index 0000000..652a9c8
--- /dev/null
+++ b/tests/znew-k
@@ -0,0 +1,42 @@
+#!/bin/sh
+# Check that znew -K works without compress(1).
+
+# Copyright (C) 2010 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+# limit so don't run it by default.
+
+if test "$VERBOSE" = yes; then
+  set -x
+  gzip --version
+fi
+
+: ${srcdir=.}
+. "$srcdir/tests/init.sh"; path_prepend_ "$PWD"
+
+cat <<'EOF' >compress || framework_failure
+#!/bin/sh
+echo >&2 'compress have been called'
+exit 1
+EOF
+chmod +x compress || framework_failure
+
+printf '%1012977s' ' ' | gzip -c >znew-k.Z || framework_failure
+
+fail=0
+
+znew -K znew-k.Z || fail=1
+test -f znew-k.Z || fail=1
+
+Exit $fail
diff --git a/znew.1 b/znew.1
index 5cfb472..dcdf84f 100644
--- a/znew.1
+++ b/znew.1
@@ -27,7 +27,8 @@ Use the slowest compression method (optimal compression).
 Use pipes for the conversion to reduce disk space usage.
 .TP
 .B \-K
-Keep a .Z file when it is smaller than the .gz file
+Keep a .Z file when it is smaller than the .gz file; implies
+.BR -t .
 .SH "SEE ALSO"
 gzip(1), zmore(1), zdiff(1), zgrep(1), zforce(1), gzexe(1), compress(1)
 .SH BUGS
diff --git a/znew.in b/znew.in
index c7cdfc8..43f3148 100644
--- a/znew.in
+++ b/znew.in
@@ -41,7 +41,7 @@ Options:
   -v     Verbose; display name and statistics for each file compressed.
   -9     Use the slowest compression method (optimal compression).
   -P     Use pipes for the conversion to reduce disk space usage.
-  -K     Keep a .Z file when it is smaller than the .gz file.
+  -K     Keep a .Z file when it is smaller than the .gz file; implies -t.
       --help     display this help and exit
       --version  output version information and exit
 
@@ -106,7 +106,7 @@ case "$opt" in
   *t*) check=1; opt=`echo "$opt" | sed 's/t//g'`
 esac
 case "$opt" in
-  *K*) keep=1; opt=`echo "$opt" | sed 's/K//g'`
+  *K*) keep=1; check=1; opt=`echo "$opt" | sed 's/K//g'`
 esac
 case "$opt" in
   *P*) pipe=1; opt=`echo "$opt" | sed 's/P//g'`
@@ -164,10 +164,8 @@ for i do
                              `expr \( $new + $block - 1 \) / $block`; then
     if test $pipe -eq 1; then
       rm -f "$n$ext"
-    elif test $check -eq 1; then
-      mv "$n.$$" "$n.Z" && rm -f "$n$ext"
     else
-      gzip -d "$n$ext" && compress "$n" && rm -f "$n$ext"
+      mv "$n.$$" "$n.Z" && rm -f "$n$ext"
     fi
     echo "$n.Z smaller than $n$ext -- unchanged"
 
-- 
ldv