Colorize zpool status output

If the ZFS_COLOR env variable is set, then use ANSI color
output in zpool status:

- Column headers are bold
- Degraded or offline pools/vdevs are yellow
- Non-zero error counters and faulted vdevs/pools are red
- The 'status:' and 'action:' sections are yellow if they're
  displaying a warning.

Signed-off-by: Tony Hutter <[email protected]>

config/ax_require_defined.m4

@@ -0,0 +1,37 @@
+# ===========================================================================
+#    https://www.gnu.org/software/autoconf-archive/ax_require_defined.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_REQUIRE_DEFINED(MACRO)
+#
+# DESCRIPTION
+#
+#   AX_REQUIRE_DEFINED is a simple helper for making sure other macros have
+#   been defined and thus are available for use.  This avoids random issues
+#   where a macro isn't expanded.  Instead the configure script emits a
+#   non-fatal:
+#
+#     ./configure: line 1673: AX_CFLAGS_WARN_ALL: command not found
+#
+#   It's like AC_REQUIRE except it doesn't expand the required macro.
+#
+#   Here's an example:
+#
+#     AX_REQUIRE_DEFINED([AX_CHECK_LINK_FLAG])
+#
+# LICENSE
+#
+#   Copyright (c) 2014 Mike Frysinger <[email protected]>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 2
+
+AC_DEFUN([AX_REQUIRE_DEFINED], [dnl
+  m4_ifndef([$1], [m4_fatal([macro ]$1[ is not defined; is a m4 file missing?])])
+])dnl AX_REQUIRE_DEFINED

config/user.m4

@@ -2,6 +2,7 @@ dnl #
 dnl # Default ZFS user configuration
 dnl #
 AC_DEFUN([ZFS_AC_CONFIG_USER], [
+	AX_WITH_CURSES
 	ZFS_AC_CONFIG_USER_GETTEXT
 	ZFS_AC_CONFIG_USER_MOUNT_HELPER
 	ZFS_AC_CONFIG_USER_UDEV

include/libzutil.h

@@ -142,6 +142,18 @@ extern void zpool_dump_ddt(const ddt_stat_t *, const ddt_histogram_t *);
 extern int zpool_history_unpack(char *, uint64_t, uint64_t *, nvlist_t ***,
     uint_t *);
 
+/*
+ * List of colors to use ("FG" for forground color, "BG" for background)
+ */
+#define	ANSI_RED	"\033[0;31m"
+#define	ANSI_YELLOW	"\033[0;33m"
+#define	ANSI_RESET	"\033[0m"
+#define	ANSI_BOLD	"\033[1m"
+
+void color_start(char *color);
+void color_end(void);
+int printf_color(char *color, char *format, ...);
+
 #ifdef	__cplusplus
 }
 #endif

lib/libzfs/Makefile.am

@@ -71,7 +71,7 @@ endif
 
 libzfs_la_LDFLAGS = -version-info 2:0:0
 
-libzfs_la_LIBADD += -lm $(LIBSSL)
+libzfs_la_LIBADD += -lm $(LIBSSL) $(CURSES_LIBS)
 
 EXTRA_DIST = $(libzfs_pc_DATA) $(USER_C)
 

lib/libzfs/libzfs_util.c

@@ -46,6 +46,18 @@
 #include <sys/types.h>
 #include <sys/wait.h>
 
+#ifdef HAVE_CURSES_COLOR
+#include <curses.h>
+#include <term.h>
+/*
+ * For some reason, term.h #defines 'lines' (in lower case) as a macro.
+ * Since we also have a variable named 'lines', undefine the macro here.
+ */
+#ifdef lines
+#undef lines
+#endif
+#endif
+
 #include <libzfs.h>
 #include <libzfs_core.h>
 
@@ -1886,3 +1898,101 @@ zfs_version_print(void)
 
 	return (0);
 }
+
+/*
+ * Return 1 if the user request ANSI color output, and our terminal supports
+ * it.  Return 0 for no color.
+ */
+static int
+use_color(void)
+{
+#ifdef HAVE_CURSES_COLOR
+	static int use_color = -1;
+
+	/*
+	 * Optimization:
+	 *
+	 * For each zpool invocation, we do a single check to see if we should
+	 * be using color or not, and cache that value for the lifetime of the
+	 * the zpool command.  That makes it cheap to call use_color() when
+	 * we're printing with color.  We assume that the settings are not going
+	 * to change during the invocation of a zpool command (the user isn't
+	 * going to change the ZFS_COLOR value while zpool is running, for
+	 * example).
+	 */
+	if (use_color != -1) {
+		/*
+		 * We've already figured out if we should be using color or
+		 * not.  Return the cached value.
+		 */
+		return (use_color);
+	}
+
+	/*
+	 * The user sets the ZFS_COLOR env var set to enable zpool ANSI color
+	 * output.  However if NO_COLOR is set (https://no-color.org/) then
+	 * don't use it.
+	 */
+	if (libzfs_envvar_is_set("ZFS_COLOR") &&
+	    !libzfs_envvar_is_set("NO_COLOR")) {
+		/*
+		 * User has requested color, check if our terminal supports it.
+		 * If it's not supported, then silently don't use it.
+		 */
+		if (setupterm(NULL, fileno(stdout), (int *)0) == 0 &&
+		    tigetnum("colors") >= 16) {
+			/* Color supported */
+			use_color = 1;
+		} else {
+			use_color = 0;
+		}
+		return (use_color);
+	}
+#endif
+	return (0);
+}
+
+/*
+ * color_start() and color_end() are used for when you want to colorize a block
+ * of text.  For example:
+ *
+ * color_start(ANSI_RED_FG)
+ * printf("hello");
+ * printf("world");
+ * color_end();
+ */
+void
+color_start(char *color)
+{
+	if (use_color())
+		printf("%s", color);
+}
+
+void
+color_end(void)
+{
+	if (use_color())
+		printf(ANSI_RESET);
+}
+
+/* printf() with a color.  If color is NULL, then do a normal printf. */
+int
+printf_color(char *color, char *format, ...)
+{
+	char buf[4090];
+	va_list aptr;
+	int rc;
+
+	if (color)
+		color_start(color);
+
+	va_start(aptr, format);
+	vsprintf(buf, format, aptr);
+	va_end(aptr);
+	rc = printf("%s", buf);
+
+	if (color)
+		color_end();
+
+	return (rc);
+}

man/man8/zpool.8

@@ -2867,6 +2867,12 @@ or
 by setting
 .Sy ZFS_VDEV_DEVID_OPT_OUT .
 .El
+.Bl -tag -width "ZFS_COLOR"
+.It Ev ZFS_COLOR
+Use ANSI color in
+.Nm zpool status
+output.
+.El
 .Bl -tag -width "ZPOOL_SCRIPTS_AS_ROOT"
 .It Ev ZPOOL_SCRIPTS_AS_ROOT
 Allow a privileged user to run the

tests/runfiles/common.run

@@ -283,7 +283,7 @@ tests = ['zfs_upgrade_001_pos', 'zfs_upgrade_002_pos', 'zfs_upgrade_003_pos',
 tags = ['functional', 'cli_root', 'zfs_upgrade']
 
 [tests/functional/cli_root/zpool]
-tests = ['zpool_001_neg', 'zpool_002_pos', 'zpool_003_pos']
+tests = ['zpool_001_neg', 'zpool_002_pos', 'zpool_003_pos', 'zpool_colors']
 tags = ['functional', 'cli_root', 'zpool']
 
 [tests/functional/cli_root/zpool_add]

tests/zfs-tests/tests/functional/cli_root/zpool/Makefile.am

@@ -4,4 +4,5 @@ dist_pkgdata_SCRIPTS = \
 	cleanup.ksh \
 	zpool_001_neg.ksh \
 	zpool_002_pos.ksh \
-	zpool_003_pos.ksh
+	zpool_003_pos.ksh \
+	zpool_colors.ksh

tests/zfs-tests/tests/functional/cli_root/zpool/setup.ksh

@@ -29,4 +29,4 @@
 
 DISK=${DISKS%% *}
 
-default_setup $DISK
+default_mirror_setup $DISKS

tests/zfs-tests/tests/functional/cli_root/zpool/zpool_colors.ksh

@@ -0,0 +1,85 @@
+#!/bin/ksh -p
+#
+# CDDL HEADER START
+#
+# This file and its contents are supplied under the terms of the
+# Common Development and Distribution License ("CDDL"), version 1.0.
+# You may only use this file in accordance with the terms of version
+# 1.0 of the CDDL.
+#
+# A full copy of the text of the CDDL should have accompanied this
+# source.  A copy of the CDDL is also available via the Internet at
+# http://www.illumos.org/license/CDDL.
+#
+# CDDL HEADER END
+#
+# Copyright (c) 2019 Lawrence Livermore National Security, LLC.
+
+. $STF_SUITE/include/libtest.shlib
+
+#
+# DESCRIPTION:
+#	Test that zpool status colored output works.
+#
+# STRATEGY:
+# 1. Create a pool with a bunch of errors and force fault one of the vdevs.
+# 2. Look for 'pool:' in bold.
+# 3. Look for 'DEGRADED' in yellow
+# 3. Look for 'FAULTED' in red
+#
+
+verify_runnable "both"
+
+function cleanup
+{
+	zinject -c all
+}
+
+log_onexit cleanup
+
+log_assert "Test colorized zpool status output"
+
+DISK2="$(echo $DISKS | cut -d' ' -f2)"
+DISK3="$(echo $DISKS | cut -d' ' -f3)"
+
+log_must dd if=/dev/urandom of=/$TESTDIR/testfile bs=10M count=1
+
+log_must zpool export $TESTPOOL
+log_must zpool import $TESTPOOL
+
+log_note "$(ZFS_COLOR=1 zpool status)"
+log_must zpool offline -f $TESTPOOL $DISK3
+log_must wait_for_degraded $TESTPOOL
+log_must zinject -d $DISK2 -e io -T read -f 20 $TESTPOOL
+log_must zinject -d $DISK2 -e io -T write -f 20 $TESTPOOL
+
+
+log_must zpool scrub $TESTPOOL
+log_must wait_scrubbed $TESTPOOL
+log_must zinject -c all
+
+
+# Replace the escape codes with "ESC" so they're easier to grep
+out="$(ZFS_COLOR=1 zpool status | grep -E 'pool:|DEGRADED' | \
+    sed -r 's/\s+//g;'$(echo -e 's/\033/ESC/g'))"
+
+log_note "Look for 'pool:' in bold"
+log_must eval "echo \"$out\" | grep -q 'ESC\[1mpool:ESC\[0m' "
+
+log_note "Look for 'DEGRADED' in yellow"
+log_must eval "echo \"$out\" | grep -q 'ESC\[0;33mDEGRADEDESC\[0m'"
+
+#
+# The escape code for 'FAULTED' is a little more tricky.  The line starts like
+# this:
+#
+# <start red escape code> loop2  FAULTED <end escape code>
+#
+# Luckily, awk counts the start and end escape codes as separate fields, so
+# we can easily remove the vdev field to get what we want.
+#
+out="$(ZFS_COLOR=1 zpool status | awk '/FAULTED/{print $1$3$4}' | sed -r $(echo -e 's/\033/ESC/g'))"
+log_note "Look for 'FAULTED' in red"
+log_must eval "echo \"$out\" | grep -q 'ESC\[0;31mFAULTEDESC\[0m'"
+
+log_pass "zpool status displayed colors"