display error on module window

- Currently errors are displayed on stdout. This patch puts the
error on subscreens also.
- bug 1298171

Signed-off-by: Sanjay Singh Rawat <sanjay.rawat@linaro.org>
diff --git a/display.c b/display.c
index c0afe03..0000ee9 100644
--- a/display.c
+++ b/display.c
@@ -270,6 +270,15 @@
 	return wmove(windata[win].pad, 0, 0);
 }
 
+void display_message(int win, char *buf)
+{
+	display_reset_cursor(win);
+	wattron(windata[win].pad, WA_BOLD);
+	wprintw(windata[win].pad, "%s\n", buf);
+	wattroff(windata[win].pad, WA_BOLD);
+	display_refresh_pad(win);
+}
+
 int display_print_line(int win, int line, char *str, int bold, void *data)
 {
 	int attr = 0;
diff --git a/display.h b/display.h
index b28d26e..e3a1529 100644
--- a/display.h
+++ b/display.h
@@ -25,6 +25,7 @@
 
 extern int display_print_line(int window, int line, char *str,
 			      int bold, void *data);
+extern void display_message(int window, char *buf);
 
 extern int display_refresh_pad(int window);
 extern int display_reset_cursor(int window);
diff --git a/gpio.c b/gpio.c
index 4006a5a..ea97278 100644
--- a/gpio.c
+++ b/gpio.c
@@ -45,6 +45,7 @@
 } *gpios_info;
 
 static struct tree *gpio_tree = NULL;
+static bool gpio_error = false;
 
 static struct gpio_info *gpio_alloc(void)
 {
@@ -258,6 +259,11 @@
 
 static int gpio_display(bool refresh)
 {
+	if (gpio_error) {
+		display_message(GPIO, "error: path " SYSFS_GPIO " not found");
+		return -2;
+	}
+
 	if (refresh && read_gpio_info(gpio_tree))
 		return -1;
 
@@ -355,6 +361,15 @@
  */
 int gpio_init(void)
 {
+	int ret = 0;
+
+	ret = display_register(GPIO, &gpio_ops);
+	if (!ret)
+		printf("error: gpio display register failed");
+
+	if (access(SYSFS_GPIO, F_OK))
+		gpio_error = true; /* set the flag */
+
 	export_gpios();
 
 	gpio_tree = tree_load(SYSFS_GPIO, gpio_filter_cb, false);
@@ -364,5 +379,5 @@
 	if (fill_gpio_tree())
 		return -1;
 
-	return display_register(GPIO, &gpio_ops);
+	return ret;
 }
diff --git a/regulator.c b/regulator.c
index 9cd89fd..27d75b6 100644
--- a/regulator.c
+++ b/regulator.c
@@ -68,6 +68,7 @@
 };
 
 static struct tree *reg_tree;
+static bool regulator_error = false;
 
 static struct regulator_info *regulator_alloc(void)
 {
@@ -220,6 +221,12 @@
 
 static int regulator_display(bool refresh)
 {
+	if (regulator_error) {
+		display_message(REGULATOR,
+			"error: path " SYSFS_REGULATOR " not found");
+		return -2;
+	}
+
 	if (refresh && read_regulator_info(reg_tree))
 		return -1;
 
@@ -255,6 +262,15 @@
 
 int regulator_init(void)
 {
+	int ret = 0;
+
+	ret = display_register(REGULATOR, &regulator_ops);
+	if (!ret)
+		printf("error: regulator display register failed");
+
+	if (access(SYSFS_REGULATOR, F_OK))
+		regulator_error = true; /* set the flag */
+
 	reg_tree = tree_load(SYSFS_REGULATOR, regulator_filter_cb, false);
 	if (!reg_tree)
 		return -1;
@@ -262,5 +278,5 @@
 	if (fill_regulator_tree())
 		return -1;
 
-	return display_register(REGULATOR, &regulator_ops);
+	return ret;
 }
diff --git a/sensor.c b/sensor.c
index 0645d25..bf67277 100644
--- a/sensor.c
+++ b/sensor.c
@@ -31,6 +31,7 @@
 #define SYSFS_SENSOR "/sys/class/hwmon"
 
 static struct tree *sensor_tree;
+static bool sensor_error = false;
 
 struct temp_info {
 	char name[NAME_MAX];
@@ -272,6 +273,12 @@
 
 static int sensor_display(bool refresh)
 {
+	if (sensor_error) {
+		display_message(SENSOR,
+			"error: path " SYSFS_SENSOR " not found");
+		return -2;
+	}
+
 	if (refresh && read_sensor_info(sensor_tree))
 		return -1;
 
@@ -284,6 +291,15 @@
 
 int sensor_init(void)
 {
+	int ret = 0;
+
+	ret = display_register(SENSOR, &sensor_ops);
+	if (!ret)
+		printf("error: sensor display register failed");
+
+	if (access(SYSFS_SENSOR, F_OK))
+		sensor_error = true; /* set the flag */
+
 	sensor_tree = tree_load(SYSFS_SENSOR, sensor_filter_cb, false);
 	if (!sensor_tree)
 		return -1;
@@ -291,5 +307,5 @@
 	if (fill_sensor_tree())
 		return -1;
 
-	return display_register(SENSOR, &sensor_ops);
+	return ret;
 }