pager support: some improvements

When QUILT_PAGER is set to an empty value, do not paginate.
Document QUILT_PAGER in the man page.
Clean things up a little.
Add a workaround in quilt.quiltrc for color output when $LESS is defined.

4 files changed, 39 insertions, 22 deletions

diff --git a/doc/quilt.1.in b/doc/quilt.1.in
index 39ae680..85ba44e 100644
--- a/doc/quilt.1.in
+++ b/doc/quilt.1.in
@@ -200,6 +200,13 @@ If this variable is set to anything, no timestamp will be included.  This
 is a shortcut to adding --no-timestamps to both QUILT_DIFF_ARGS and
 QUILT_REFRESH_ARGS.
 
+.IP QUILT_PAGER 4
+
+Th pager quilt shall use for commands which produce paginated output. If
+unset, the values of GIT_PAGER or PAGER is used.  If none of these variables
+is set, "less" is used.  An empty value indicates that no pager should be
+used.
+
 .IP EDITOR 4
 
 The program to run to edit files.  If it isn't redefined in the
diff --git a/quilt.changes b/quilt.changes
index 99fa25b..244fb00 100644
--- a/quilt.changes
+++ b/quilt.changes
@@ -1,4 +1,15 @@
 -------------------------------------------------------------------
+Fri Nov 20 22:43:33 CET 2009 - agruen@suse.de
+
+- Add pagination support (code based on topgit; patch from Bert
+  Wesarg <bert.wesarg@googlemail.com>).
+- When QUILT_PAGER is set to an empty value, do not paginate.
+- Document QUILT_PAGER in the man page.
+- Clean things up a little.
+- Add a workaround in quilt.quiltrc for color output when $LESS
+  is defined.
+
+-------------------------------------------------------------------
 Fri Nov 20 20:40:55 CET 2009 - pth@novell.com
 
 - Enable quilt to handle compressed tarballs and patches that were
diff --git a/quilt.quiltrc b/quilt.quiltrc
index b815d32..cd44500 100644
--- a/quilt.quiltrc
+++ b/quilt.quiltrc
@@ -18,6 +18,10 @@ QUILT_REFRESH_ARGS="--no-timestamps --backup"
 QUILT_SERIES_ARGS="--color=auto"
 QUILT_PATCHES_ARGS="--color=auto"
 
+# When non-default less options are used, add the -R option so that less outputs
+# ANSI color escape codes "raw".
+[ -n "$LESS" ] && QUILT_PAGER="less -R"
+
 # (Add "-p ab" to QUILT_DIFF_ARGS and QUILT_REFRESH_ARGS to get
 #  -p1 style diffs with a/file and b/file filenams in headers
 #  instead of dir.orig/file and dir/file.)
diff --git a/quilt/scripts/patchfns.in b/quilt/scripts/patchfns.in
index b0ed135..be6228e 100644
--- a/quilt/scripts/patchfns.in
+++ b/quilt/scripts/patchfns.in
@@ -976,36 +976,31 @@ quilt_command()
 	QUILT_COMMAND="" bash $BASH_OPTS -c "${SUBDIR:+cd $SUBDIR;} . $QUILT_DIR/$command" "quilt $command" "$@"
 }
 
-# isatty FD
-isatty()
-{
-	test -t $1
-}
-
-# setup_pager
 # Spawn pager process and redirect the rest of our output to it
 setup_pager()
 {
-	isatty 1 || return 0
-
-	# QUILT_PAGER = GIT_PAGER | PAGER | less
-	# NOTE: GIT_PAGER='' is significant
-	QUILT_PAGER=${GIT_PAGER-${PAGER-less}}
+	test -t 1 || return 0
 
-	[ -z "$QUILT_PAGER"  -o  "$QUILT_PAGER" = "cat" ]  && return 0
+	# QUILT_PAGER = QUILT_PAGER | GIT_PAGER | PAGER | less
+	# NOTE: QUILT_PAGER='' is significant
+	QUILT_PAGER=${QUILT_PAGER-${GIT_PAGER-${PAGER-less}}}
 
-	# now spawn pager
-	export LESS="${LESS:-FRSX}"	# as in pager.c:pager_preexec()
+	[ -z "$QUILT_PAGER" -o "$QUILT_PAGER" = "cat" ]  && return 0
 
-	_pager_fifo_dir="$(gen_tempfile -d)"
-	_pager_fifo="$_pager_fifo_dir/0"
-	mkfifo -m 600 "$_pager_fifo"
+	export LESS="${LESS:-FRSX}"
 
-	"$QUILT_PAGER" < "$_pager_fifo" &
-	exec > "$_pager_fifo"		# dup2(pager_fifo.in, 1)
+	# NOTE: with "exec > >($pager)" there is no way to get the pid of the
+	# pager so we can't wait for it to complete.  Otherwise we wouldn't
+	# need temporary files here.  Alternatively, in recent versions of
+	# bash, a coprocess could be used instead.
 
-	# atexit(close(1); wait pager)
-	add_exit_handler "exec >&-; rm \"$_pager_fifo\"; rmdir \"$_pager_fifo_dir\"; wait"
+	local pager_fifo_dir pager_fifo
+	pager_fifo_dir="$(gen_tempfile -d)"
+	pager_fifo="$pager_fifo_dir/0"
+	mkfifo -m 600 "$pager_fifo"
+	"$QUILT_PAGER" < "$pager_fifo" &
+	exec > "$pager_fifo"
+	add_exit_handler "exec >&-; rm $pager_fifo; rmdir $pager_fifo_dir; wait"
 }
 
 #