On 2024-07-31 17:01:09+0000, Shuah Khan wrote:
On 7/31/24 12:32, Thomas Weißschuh wrote:
The implementation is limited and only supports numeric arguments.
I would like to see more information in here. Why is this needed etc. etc.
Ack.
Signed-off-by: Thomas Weißschuh linux@weissschuh.net
tools/include/nolibc/stdio.h | 93 ++++++++++++++++++++++++++++ tools/testing/selftests/nolibc/nolibc-test.c | 59 ++++++++++++++++++ 2 files changed, 152 insertions(+)
diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h index c968dbbc4ef8..d63c45c06d8e 100644 --- a/tools/include/nolibc/stdio.h +++ b/tools/include/nolibc/stdio.h @@ -348,6 +348,99 @@ int printf(const char *fmt, ...) return ret; } +static __attribute__((unused)) +int vsscanf(const char *str, const char *format, va_list args)
Is there a reason why you didn't use the same code in lib/vsprintf.c? You could simply duplicate the code here?
lib/vsprintf.c is GPL-2.0-only while nolibc is LGPL-2.1 OR MIT, so code reuse isn't really possible. Furthermore I think the vsprintf.c implements the custom kernel formats, while nolibc should use posix ones.
With all these libc functionality added, it isn't nolibc looks like :)
Well :-)
The main motivation is to provide kselftests compatibility. Maybe Willy disagrees.
+{
- uintmax_t uval;
- intmax_t ival;
- int base;
- char *endptr;
- int matches;
- int lpref;
- matches = 0;
- while (1) {
if (*format == '%') {lpref = 0;format++;if (*format == 'l') {lpref = 1;format++;if (*format == 'l') {lpref = 2;format++;}}if (*format == '%') {if ('%' != *str)goto done;str++;format++;continue;} else if (*format == 'd') {ival = strtoll(str, &endptr, 10);if (lpref == 0)*va_arg(args, int *) = ival;else if (lpref == 1)*va_arg(args, long *) = ival;else if (lpref == 2)*va_arg(args, long long *) = ival;} else if (*format == 'u' || *format == 'x' || *format == 'X') {base = *format == 'u' ? 10 : 16;uval = strtoull(str, &endptr, base);if (lpref == 0)*va_arg(args, unsigned int *) = uval;else if (lpref == 1)*va_arg(args, unsigned long *) = uval;else if (lpref == 2)*va_arg(args, unsigned long long *) = uval;} else if (*format == 'p') {*va_arg(args, void **) = (void *)strtoul(str, &endptr, 16);} else {SET_ERRNO(EILSEQ);goto done;}format++;str = endptr;matches++;} else if (*format == '\0') {goto done;} else if (isspace(*format)) {while (isspace(*format))format++;while (isspace(*str))str++;} else if (*format == *str) {format++;str++;} else {if (!matches)matches = EOF;goto done;}- }
+done:
- return matches;
+}
+static __attribute__((unused, format(scanf, 2, 3))) +int sscanf(const char *str, const char *format, ...) +{
- va_list args;
- int ret;
- va_start(args, format);
- ret = vsscanf(str, format, args);
- va_end(args);
- return ret;
+}
- static __attribute__((unused)) void perror(const char *msg) {
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c index 093d0512f4c5..addbceb0b276 100644 --- a/tools/testing/selftests/nolibc/nolibc-test.c +++ b/tools/testing/selftests/nolibc/nolibc-test.c @@ -1277,6 +1277,64 @@ static int expect_vfprintf(int llen, int c, const char *expected, const char *fm return ret; } +static int test_scanf(void) +{
- unsigned long long ull;
- unsigned long ul;
- unsigned int u;
- long long ll;
- long l;
- void *p;
- int i;
- if (sscanf("", "foo") != EOF)
return 1;- if (sscanf("foo", "foo") != 0)
return 2;- if (sscanf("123", "%d", &i) != 1)
return 3;- if (i != 123)
return 4;- if (sscanf("a123b456c0x90", "a%db%uc%p", &i, &u, &p) != 3)
return 5;- if (i != 123)
return 6;- if (u != 456)
return 7;- if (p != (void *)0x90)
return 8;- if (sscanf("a b1", "a b%d", &i) != 1)
return 9;- if (i != 1)
return 10;- if (sscanf("a%1", "a%%%d", &i) != 1)
return 11;- if (i != 1)
return 12;- if (sscanf("1|2|3|4|5|6",
"%d|%ld|%lld|%u|%lu|%llu",&i, &l, &ll, &u, &ul, &ull) != 6)return 13;- if (i != 1 || l != 2 || ll != 3 ||
u != 4 || ul != 5 || ull != 6)return 14;- return 0;
Can we simplify this code? It is hard to read code with too many conditions. Maybe defining an array test conditions instead of a series ifs.
I tried that and didn't find a way. Any pointers are welcome.
- static int run_vfprintf(int min, int max) { int test;
@@ -1298,6 +1356,7 @@ static int run_vfprintf(int min, int max) CASE_TEST(char); EXPECT_VFPRINTF(1, "c", "%c", 'c'); break; CASE_TEST(hex); EXPECT_VFPRINTF(1, "f", "%x", 0xf); break; CASE_TEST(pointer); EXPECT_VFPRINTF(3, "0x1", "%p", (void *) 0x1); break;
CASE_TEST(scanf); EXPECT_ZR(1, test_scanf()); break;thanks, -- Shuah