1 files changed, 183 insertions, 0 deletions
diff --git a/lib/color.c b/lib/color.c
new file mode 100644
index 0000000..5997684
--- /dev/null
+++ b/lib/color.c
@@ -0,0 +1,183 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <linux/if.h>
+
+#include "color.h"
+#include "utils.h"
+
+static void set_color_palette(void);
+
+enum color {
+	C_RED,
+	C_GREEN,
+	C_YELLOW,
+	C_BLUE,
+	C_MAGENTA,
+	C_CYAN,
+	C_WHITE,
+	C_BOLD_RED,
+	C_BOLD_GREEN,
+	C_BOLD_YELLOW,
+	C_BOLD_BLUE,
+	C_BOLD_MAGENTA,
+	C_BOLD_CYAN,
+	C_BOLD_WHITE,
+	C_CLEAR
+};
+
+static const char * const color_codes[] = {
+	"\e[31m",
+	"\e[32m",
+	"\e[33m",
+	"\e[34m",
+	"\e[35m",
+	"\e[36m",
+	"\e[37m",
+	"\e[1;31m",
+	"\e[1;32m",
+	"\e[1;33m",
+	"\e[1;34m",
+	"\e[1;35m",
+	"\e[1;36m",
+	"\e[1;37m",
+	"\e[0m",
+	NULL,
+};
+
+/* light background */
+static enum color attr_colors_light[] = {
+	C_CYAN,
+	C_YELLOW,
+	C_MAGENTA,
+	C_BLUE,
+	C_GREEN,
+	C_RED,
+	C_CLEAR,
+};
+
+/* dark background */
+static enum color attr_colors_dark[] = {
+	C_BOLD_CYAN,
+	C_BOLD_YELLOW,
+	C_BOLD_MAGENTA,
+	C_BOLD_BLUE,
+	C_BOLD_GREEN,
+	C_BOLD_RED,
+	C_CLEAR
+};
+
+static int is_dark_bg;
+static int color_is_enabled;
+
+static void enable_color(void)
+{
+	color_is_enabled = 1;
+	set_color_palette();
+}
+
+bool check_enable_color(int color, int json)
+{
+	if (json || color == COLOR_OPT_NEVER)
+		return false;
+
+	if (color == COLOR_OPT_ALWAYS || isatty(fileno(stdout))) {
+		enable_color();
+		return true;
+	}
+	return false;
+}
+
+bool matches_color(const char *arg, int *val)
+{
+	char *dup, *p;
+
+	if (!val)
+		return false;
+
+	dup = strdupa(arg);
+	p = strchrnul(dup, '=');
+	if (*p)
+		*(p++) = '\0';
+
+	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;
+}
+
+static void set_color_palette(void)
+{
+	char *p = getenv("COLORFGBG");
+
+	/*
+	 * COLORFGBG environment variable usually contains either two or three
+	 * values separated by semicolons; we want the last value in either case.
+	 * If this value is 0-6 or 8, background is dark.
+	 */
+	if (p && (p = strrchr(p, ';')) != NULL
+		&& ((p[1] >= '0' && p[1] <= '6') || p[1] == '8')
+		&& p[2] == '\0')
+		is_dark_bg = 1;
+}
+
+__attribute__((format(printf, 3, 4)))
+int color_fprintf(FILE *fp, enum color_attr attr, const char *fmt, ...)
+{
+	int ret = 0;
+	va_list args;
+
+	va_start(args, fmt);
+
+	if (!color_is_enabled || attr == COLOR_NONE) {
+		ret = vfprintf(fp, fmt, args);
+		goto end;
+	}
+
+	ret += fprintf(fp, "%s", color_codes[is_dark_bg ?
+		attr_colors_dark[attr] : attr_colors_light[attr]]);
+
+	ret += vfprintf(fp, fmt, args);
+	ret += fprintf(fp, "%s", color_codes[C_CLEAR]);
+
+end:
+	va_end(args);
+	return ret;
+}
+
+enum color_attr ifa_family_color(__u8 ifa_family)
+{
+	switch (ifa_family) {
+	case AF_INET:
+		return COLOR_INET;
+	case AF_INET6:
+		return COLOR_INET6;
+	default:
+		return COLOR_NONE;
+	}
+}
+
+enum color_attr oper_state_color(__u8 state)
+{
+	switch (state) {
+	case IF_OPER_UP:
+		return COLOR_OPERSTATE_UP;
+	case IF_OPER_DOWN:
+		return COLOR_OPERSTATE_DOWN;
+	default:
+		return COLOR_NONE;
+	}
+}