kfifo: add explicit error checking in byte stream example

Provide a static array of expected items that kfifo should contain at the end of the test to validate it. Signed-off-by: Andrea Righi <arighi@develer.com> Cc: Stefani Seibold <stefani@seibold.net> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kfifo: add explicit error checking in byte stream example
Provide a static array of expected items that kfifo should contain at the end of the test to validate it. Signed-off-by: Andrea Righi <arighi@develer.com> Cc: Stefani Seibold <stefani@seibold.net> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Righi · Linus Torvalds
1 parent 5ddf83912c
Showing 1 changed file with 27 additions and 6 deletions Side-by-side Diff
samples/kfifo/bytestream-example.c
@@ -44,10 +44,17 @@
 static DECLARE_KFIFO(test, unsigned char, FIFO_SIZE);
 #endif
  
+static unsigned char expected_result[FIFO_SIZE] = {
+	 3,  4,  5,  6,  7,  8,  9,  0,
+	 1, 20, 21, 22, 23, 24, 25, 26,
+	27, 28, 29, 30, 31, 32, 33, 34,
+	35, 36, 37, 38, 39, 40, 41, 42,
+};
+
 static int __init testfunc(void)
 {
 	unsigned char	buf[6];
-	unsigned char	i;
+	unsigned char	i, j;
 	unsigned int	ret;
  
 	printk(KERN_INFO "byte stream fifo test start\n");
@@ -83,10 +90,19 @@
  
 	printk(KERN_INFO "queue len: %u\n", kfifo_len(&test));
  
-	/* print out all values in the fifo */
-	while (kfifo_get(&test, &i))
-		printk("%d ", i);
-	printk("\n");
+	/* check the correctness of all values in the fifo */
+	j = 0;
+	while (kfifo_get(&test, &i)) {
+		if (i != expected_result[j++]) {
+			printk(KERN_WARNING "value mismatch: test failed\n");
+			return -EIO;
+		}
+	}
+	if (j != ARRAY_SIZE(expected_result)) {
+		printk(KERN_WARNING "size mismatch: test failed\n");
+		return -EIO;
+	}
+	printk(KERN_INFO "test passed\n");
  
 	return 0;
 }
@@ -142,7 +158,12 @@
 #else
 	INIT_KFIFO(test);
 #endif
-	testfunc();
+	if (testfunc() < 0) {
+#ifdef DYNAMIC
+		kfifo_free(&test);
+#endif
+		return -EIO;
+	}
  
 	if (proc_create(PROC_FIFO, 0, NULL, &fifo_fops) == NULL) {
 #ifdef DYNAMIC
...	...	@@ -44,10 +44,17 @@
44	44	static DECLARE_KFIFO(test, unsigned char, FIFO_SIZE);
45	45	#endif
46	46
	47	+static unsigned char expected_result[FIFO_SIZE] = {
	48	+ 3, 4, 5, 6, 7, 8, 9, 0,
	49	+ 1, 20, 21, 22, 23, 24, 25, 26,
	50	+ 27, 28, 29, 30, 31, 32, 33, 34,
	51	+ 35, 36, 37, 38, 39, 40, 41, 42,
	52	+};
	53	+
47	54	static int __init testfunc(void)
48	55	{
49	56	unsigned char buf[6];
50		- unsigned char i;
	57	+ unsigned char i, j;
51	58	unsigned int ret;
52	59
53	60	printk(KERN_INFO "byte stream fifo test start\n");
...	...	@@ -83,10 +90,19 @@
83	90
84	91	printk(KERN_INFO "queue len: %u\n", kfifo_len(&test));
85	92
86		- /* print out all values in the fifo */
87		- while (kfifo_get(&test, &i))
88		- printk("%d ", i);
89		- printk("\n");
	93	+ /* check the correctness of all values in the fifo */
	94	+ j = 0;
	95	+ while (kfifo_get(&test, &i)) {
	96	+ if (i != expected_result[j++]) {
	97	+ printk(KERN_WARNING "value mismatch: test failed\n");
	98	+ return -EIO;
	99	+ }
	100	+ }
	101	+ if (j != ARRAY_SIZE(expected_result)) {
	102	+ printk(KERN_WARNING "size mismatch: test failed\n");
	103	+ return -EIO;
	104	+ }
	105	+ printk(KERN_INFO "test passed\n");
90	106
91	107	return 0;
92	108	}
...	...	@@ -142,7 +158,12 @@
142	158	#else
143	159	INIT_KFIFO(test);
144	160	#endif
145		- testfunc();
	161	+ if (testfunc() < 0) {
	162	+#ifdef DYNAMIC
	163	+ kfifo_free(&test);
	164	+#endif
	165	+ return -EIO;
	166	+ }
146	167
147	168	if (proc_create(PROC_FIFO, 0, NULL, &fifo_fops) == NULL) {
148	169	#ifdef DYNAMIC