[RFC,iproute] allow overriding color option in environment

Commit Message

Stephen Hemminger Sept. 15, 2023, 4:43 p.m. UTC

For ip, tc, and bridge command introduce a new way to enable
automatic colorization via environment variable.

Example:
  $ IP_COLOR=auto ip -br show addr

Signed-off-by: Stephen Hemminger <[e-mail]>
---
 bridge/bridge.c   |  3 ++-
 include/color.h   |  1 +
 ip/ip.c           |  2 +-
 lib/color.c       | 36 +++++++++++++++++++++++++++---------
 man/man8/bridge.8 |  7 +++++++
 man/man8/ip.8     | 14 +++++++++-----
 man/man8/tc.8     |  6 ++++++
 tc/tc.c           |  2 +-
 8 files changed, 54 insertions(+), 17 deletions(-)

Patch

diff --git a/bridge/bridge.c b/bridge/bridge.c
index 704be50c70b3..f9a245cb3670 100644
--- a/bridge/bridge.c
+++ b/bridge/bridge.c
@@ -23,7 +23,6 @@  int preferred_family = AF_UNSPEC;
 int oneline;
 int show_stats;
 int show_details;
-static int color;
 int compress_vlans;
 int json;
 int timestamp;
@@ -103,6 +102,8 @@  static int batch(const char *name)
 int
 main(int argc, char **argv)
 {
+	int color = default_color("BRIDGE_COLOR");
+
 	while (argc > 1) {
 		const char *opt = argv[1];
 
diff --git a/include/color.h b/include/color.h
index 17ec56f3d7b4..8eea534f38e1 100644
--- a/include/color.h
+++ b/include/color.h
@@ -20,6 +20,7 @@  enum color_opt {
 	COLOR_OPT_ALWAYS = 2
 };
 
+int default_color(const char *argv0);
 bool check_enable_color(int color, int json);
 bool matches_color(const char *arg, int *val);
 int color_fprintf(FILE *fp, enum color_attr attr, const char *fmt, ...);
diff --git a/ip/ip.c b/ip/ip.c
index 8c046ef1df14..e15d5fe52d92 100644
--- a/ip/ip.c
+++ b/ip/ip.c
@@ -168,7 +168,7 @@  int main(int argc, char **argv)
 	const char *libbpf_version;
 	char *batch_file = NULL;
 	char *basename;
-	int color = 0;
+	int color = default_color("IP_COLOR");
 
 	/* to run vrf exec without root, capabilities might be set, drop them
 	 * if not needed as the first thing.
diff --git a/lib/color.c b/lib/color.c
index 59976847295c..9262fc51c1f2 100644
--- a/lib/color.c
+++ b/lib/color.c
@@ -93,6 +93,32 @@  bool check_enable_color(int color, int json)
 	return false;
 }
 
+static bool match_color_value(const char *arg, int *val)
+{
+	if (*arg == '\0' || !strcmp(arg, "always"))
+		*val = COLOR_OPT_ALWAYS;
+	else if (!strcmp(arg, "auto"))
+		*val = COLOR_OPT_AUTO;
+	else if (!strcmp(arg, "never"))
+		*val = COLOR_OPT_NEVER;
+	else
+		return false;
+	return true;
+}
+
+int default_color(const char *env)
+{
+	int val = COLOR_OPT_NEVER;
+	char *name;
+	size_t i;
+
+	name = getenv(env);
+	if (name && match_color_value(name, &val))
+		return val;
+
+	return COLOR_OPT_NEVER;
+}
+
 bool matches_color(const char *arg, int *val)
 {
 	char *dup, *p;
@@ -108,15 +134,7 @@  bool matches_color(const char *arg, int *val)
 	if (matches(dup, "-color"))
 		return false;
 
-	if (*p == '\0' || !strcmp(p, "always"))
-		*val = COLOR_OPT_ALWAYS;
-	else if (!strcmp(p, "auto"))
-		*val = COLOR_OPT_AUTO;
-	else if (!strcmp(p, "never"))
-		*val = COLOR_OPT_NEVER;
-	else
-		return false;
-	return true;
+	return match_color_value(p, val);
 }
 
 static void set_color_palette(void)
diff --git a/man/man8/bridge.8 b/man/man8/bridge.8
index c52c9331e2c2..58bb1ddbd26a 100644
--- a/man/man8/bridge.8
+++ b/man/man8/bridge.8
@@ -319,6 +319,13 @@  precedence. This flag is ignored if
 .B \-json
 is also given.
 
+
+The default color setting is
+.B never
+but can be overridden by the
+.B BRIDGE_COLOR
+environment variable.
+
 .TP
 .BR "\-j", " \-json"
 Output results in JavaScript Object Notation (JSON).
diff --git a/man/man8/ip.8 b/man/man8/ip.8
index 72227d44fd30..df572f47d96d 100644
--- a/man/man8/ip.8
+++ b/man/man8/ip.8
@@ -197,11 +197,15 @@  precedence. This flag is ignored if
 .B \-json
 is also given.
 
-Used color palette can be influenced by
-.BR COLORFGBG
-environment variable
-(see
-.BR ENVIRONMENT ).
+The default color setting is
+.B never
+but can be overridden by the
+.B IP_COLOR
+environment variable.
+
+The color palette used can be adjusted with
+.B COLORFGBG
+environment variable.
 
 .TP
 .BR "\-t" , " \-timestamp"
diff --git a/man/man8/tc.8 b/man/man8/tc.8
index d436d46472af..39ac6dcd1631 100644
--- a/man/man8/tc.8
+++ b/man/man8/tc.8
@@ -805,6 +805,12 @@  precedence. This flag is ignored if
 .B \-json
 is also given.
 
+The default color setting is
+.B never
+but can be overridden by the
+.B TC_COLOR
+environment variable.
+
 .TP
 .BR "\-j", " \-json"
 Display results in JSON format.
diff --git a/tc/tc.c b/tc/tc.c
index 258205004611..b7cd60d68a38 100644
--- a/tc/tc.c
+++ b/tc/tc.c
@@ -35,7 +35,6 @@  int use_iec;
 int force;
 bool use_names;
 int json;
-int color;
 int oneline;
 int brief;
 
@@ -254,6 +253,7 @@  int main(int argc, char **argv)
 {
 	const char *libbpf_version;
 	char *batch_file = NULL;
+	int color = default_color("TC_COLOR");
 	int ret;
 
 	while (argc > 1) {