From: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Date: Wed, 26 Jun 2013 21:53:11 +0000 (+0200)
Subject: pwmled: verify the input of pwmled_set_brightness
X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?p=bike-lights.git;a=commitdiff_plain;h=9fd1101ae25f19ddd7b13a4660532339ddce3309;ds=sidebyside

pwmled: verify the input of pwmled_set_brightness

Also allow different number of current levels for each output
---

diff --git a/firmware/pwmled.c b/firmware/pwmled.c
index 6158067..c156d81 100644
--- a/firmware/pwmled.c
+++ b/firmware/pwmled.c
@@ -122,20 +122,32 @@ void pwmled_set_mode(unsigned char n, unsigned char mode)
 	}
 }
 
+#define CHECK_BRIGHTNESS(var, expr, array) \
+	do { \
+		(var) = (expr); \
+		if ((var) >= sizeof(array)/sizeof(array[0])) \
+			(var) = sizeof(array)/sizeof(array[0]) - 1; \
+	} while (0)
+
 void pwmled_set_brightness(uint16_t brightness)
 {
 	unsigned char i;
 
-	adc_vals[0] = adc_targets_0[brightness & 0x7];
-	adc_vals[1] = adc_targets_0[(brightness >> 3) & 0x7];
+	CHECK_BRIGHTNESS(i, brightness & 0x7, adc_targets_0);
+	adc_vals[0] = adc_targets_0[i];
+	CHECK_BRIGHTNESS(i, (brightness >> 3) & 0x7, adc_targets_0);
+	adc_vals[1] = adc_targets_0[i];
 	adc_vals[2] = adc_vals[1];
 
-	adc_vals[3] = adc_targets_1[(brightness >> 6) & 0x7];
+	CHECK_BRIGHTNESS(i, (brightness >> 6) & 0x7, adc_targets_1);
+	adc_vals[3] = adc_targets_1[i];
 	adc_vals[4] = adc_vals[3];
 	adc_vals[5] = adc_vals[3];
 
-	adc_vals[6] = adc_targets_2[(brightness >> 9) & 0x7];
-	adc_vals[7] = adc_targets_2[(brightness >> 12) & 0x7];
+	CHECK_BRIGHTNESS(i, (brightness >> 9) & 0x7, adc_targets_2);
+	adc_vals[6] = adc_targets_2[i];
+	CHECK_BRIGHTNESS(i, (brightness >> 12) & 0x7, adc_targets_2);
+	adc_vals[7] = adc_targets_2[i];
 	adc_vals[8] = adc_vals[7];
 
 	for (i = 0; i < N_PWMLEDS; i++) {