/* * Test cases for printf facility. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/init.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/printk.h>#include <linux/random.h>#include <linux/slab.h>#include <linux/string.h> #include <linux/socket.h>#include <linux/in.h> #define BUF_SIZE 256#define FILL_CHAR '$' #define PTR1 ((void*)0x01234567)#define PTR2 ((void*)(long)(int)0xfedcba98) #if BITS_PER_LONG == 64#define PTR1_ZEROES "000000000"#define PTR1_SPACES "         "#define PTR1_STR "1234567"#define PTR2_STR "fffffffffedcba98"#define PTR_WIDTH 16#else#define PTR1_ZEROES "0"#define PTR1_SPACES " "#define PTR1_STR "1234567"#define PTR2_STR "fedcba98"#define PTR_WIDTH 8#endif#define PTR_WIDTH_STR stringify(PTR_WIDTH) static unsigned total_tests __initdata;static unsigned failed_tests __initdata;static char *test_buffer __initdata; static int __printf(4, 0) __initdo_test(int bufsize, const char *expect, int elen,	const char *fmt, va_list ap){	va_list aq;	int ret, written; 	total_tests++; 	memset(test_buffer, FILL_CHAR, BUF_SIZE);	va_copy(aq, ap);	ret = vsnprintf(test_buffer, bufsize, fmt, aq);	va_end(aq); 	if (ret != elen) {		pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n",			bufsize, fmt, ret, elen);		return 1;	} 	if (!bufsize) {		if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE)) {			pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n",				fmt);			return 1;		}		return 0;	} 	written = min(bufsize-1, elen);	if (test_buffer[written]) {		pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n",			bufsize, fmt);		return 1;	} 	if (memcmp(test_buffer, expect, written)) {		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n",			bufsize, fmt, test_buffer, written, expect);		return 1;	}	return 0;} static void __printf(3, 4) __init__test(const char *expect, int elen, const char *fmt, ...){	va_list ap;	int rand;	char *p; 	BUG_ON(elen >= BUF_SIZE); 	va_start(ap, fmt); 	/*	 * Every fmt+args is subjected to four tests: Three where we	 * tell vsnprintf varying buffer sizes (plenty, not quite	 * enough and 0), and then we also test that kvasprintf would	 * be able to print it as expected.	 */	failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap);	rand = 1 + prandom_u32_max(elen+1);	/* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */	failed_tests += do_test(rand, expect, elen, fmt, ap);	failed_tests += do_test(0, expect, elen, fmt, ap); 	p = kvasprintf(GFP_KERNEL, fmt, ap);	if (p) {		if (memcmp(p, expect, elen+1)) {			pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n",				fmt, p, expect);			failed_tests++;		}		kfree(p);	}	va_end(ap);} #define test(expect, fmt, ...)					\	__test(expect, strlen(expect), fmt, ##__VA_ARGS__) static void __inittest_basic(void){	/* Work around annoying "warning: zero-length gnu_printf format string". */	char nul = '\0'; 	test("", &nul);	test("100%", "100%%");	test("xxx%yyy", "xxx%cyyy", '%');	__test("xxx\0yyy", 7, "xxx%cyyy", '\0');} static void __inittest_number(void){	test("0x1234abcd  ", "%#-12x", 0x1234abcd);	test("  0x1234abcd", "%#12x", 0x1234abcd);	test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234);} static void __inittest_string(void){	test("", "%s%.0s", "", "123");	test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456");	test("1  |  2|3  |  4|5  ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5");	/*	 * POSIX and C99 say that a missing precision should be	 * treated as a precision of 0. However, the kernel's printf	 * implementation treats this case as if the . wasn't	 * present. Let's add a test case documenting the current	 * behaviour; should anyone ever feel the need to follow the	 * standards more closely, this can be revisited.	 */	test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c");	test("a  |   |   ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c");} static void __initplain(void){	test(PTR1_ZEROES PTR1_STR " " PTR2_STR, "%p %p", PTR1, PTR2);	/*	 * The field width is overloaded for some %p extensions to	 * pass another piece of information. For plain pointers, the	 * behaviour is slightly odd: One cannot pass either the 0	 * flag nor a precision to %p without gcc complaining, and if	 * one explicitly gives a field width, the number is no longer	 * zero-padded.	 */	test("|" PTR1_STR PTR1_SPACES "  |  " PTR1_SPACES PTR1_STR "|",	     "|%-*p|%*p|", PTR_WIDTH+2, PTR1, PTR_WIDTH+2, PTR1);	test("|" PTR2_STR "  |  " PTR2_STR "|",	     "|%-*p|%*p|", PTR_WIDTH+2, PTR2, PTR_WIDTH+2, PTR2); 	/*	 * Unrecognized %p extensions are treated as plain %p, but the	 * alphanumeric suffix is ignored (that is, does not occur in	 * the output.)	 */	test("|"PTR1_ZEROES PTR1_STR"|", "|%p0y|", PTR1);	test("|"PTR2_STR"|", "|%p0y|", PTR2);} static void __initsymbol_ptr(void){} static void __initkernel_ptr(void){} static void __initstruct_resource(void){} static void __initaddr(void){} static void __initescaped_str(void){} static void __inithex_string(void){	const char buf[3] = {0xc0, 0xff, 0xee}; 	test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee",	     "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf);	test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee",	     "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf);} static void __initmac(void){	const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05}; 	test("2d:48:d6:fc:7a:05", "%pM", addr);	test("05:7a:fc:d6:48:2d", "%pMR", addr);	test("2d-48-d6-fc-7a-05", "%pMF", addr);	test("2d48d6fc7a05", "%pm", addr);	test("057afcd6482d", "%pmR", addr);} static void __initip4(void){	struct sockaddr_in sa; 	sa.sin_family = AF_INET;	sa.sin_port = cpu_to_be16(12345);	sa.sin_addr.s_addr = cpu_to_be32(0x7f000001); 	test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr);	test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa);	sa.sin_addr.s_addr = cpu_to_be32(0x01020304);	test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa);} static void __initip6(void){} static void __initip(void){	ip4();	ip6();} static void __inituuid(void){	const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,			       0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf}; 	test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid);	test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid);	test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid);	test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid);} static void __initdentry(void){} static void __initstruct_va_format(void){} static void __initstruct_clk(void){} static void __initbitmap(void){	DECLARE_BITMAP(bits, 20);	const int primes[] = {2,3,5,7,11,13,17,19};	int i; 	bitmap_zero(bits, 20);	test("00000|00000", "%20pb|%*pb", bits, 20, bits);	test("|", "%20pbl|%*pbl", bits, 20, bits); 	for (i = 0; i < ARRAY_SIZE(primes); ++i)		set_bit(primes[i], bits);	test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits);	test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits); 	bitmap_fill(bits, 20);	test("fffff|fffff", "%20pb|%*pb", bits, 20, bits);	test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits);} static void __initnetdev_features(void){} static void __inittest_pointer(void){	plain();	symbol_ptr();	kernel_ptr();	struct_resource();	addr();	escaped_str();	hex_string();	mac();	ip();	uuid();	dentry();	struct_va_format();	struct_clk();	bitmap();	netdev_features();} static int __inittest_printf_init(void){	test_buffer = kmalloc(BUF_SIZE, GFP_KERNEL);	if (!test_buffer)		return -ENOMEM; 	test_basic();	test_number();	test_string();	test_pointer(); 	kfree(test_buffer); 	if (failed_tests == 0)		pr_info("all %u tests passed\n", total_tests);	else		pr_warn("failed %u out of %u tests\n", failed_tests, total_tests); 	return failed_tests ? -EINVAL : 0;} module_init(test_printf_init); MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>");MODULE_LICENSE("GPL");