On Sun, Apr 02, 2023 at 12:18:29PM +0000, Thomas Weißschuh wrote:
On 2023-04-02 09:51:10+0200, Willy Tarreau wrote:
On Tue, Mar 28, 2023 at 09:01:31PM +0000, Thomas Weißschuh wrote:
vfprintf() is complex and so far did not have proper tests.
This is an excellent idea, I totally agree, and I wouldn't be surprised if there were still bugs there.
The first issue I experienced was that
printf("%*s", 1, "foo") would segfault because it ignored the '*' and just tried to interpret the number "1" as string.
Yes indeed, much like many older printf() implementations as well BTW, that's a common issue when you try to write portable code ;-)
When looking for the supported features of the printf implementation there were no examples.
Indeed!
And before I try to add code to handle this case better I really want some testcases.
switch (test + __LINE__ + 1) {CASE_TEST(empty); EXPECT_VFPRINTF(0, "", ""); break;CASE_TEST(simple); EXPECT_VFPRINTF(3, "foo", "foo"); break;CASE_TEST(string); EXPECT_VFPRINTF(3, "foo", "%s", "foo"); break;CASE_TEST(number); EXPECT_VFPRINTF(4, "1234", "%d", 1234); break;CASE_TEST(negnumber); EXPECT_VFPRINTF(5, "-1234", "%d", -1234); break;CASE_TEST(unsigned); EXPECT_VFPRINTF(5, "12345", "%u", 12345); break;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, "0x0", "%p", NULL); break;I don't see a reason why not to move them to the stdlib category, since these tests are there to validate that the libc-provided functions do work. Maybe you intended to further extend it ? In this case maybe we could move that to an "stdio" category then but I'd rather avoid having one category per function or it will quickly become annoying to select groups of tests. So let's just prefix these test names with "printf_" and either merge them with "stdlib" or name the category "stdio", as you prefer.
The idea was that printf is its own very special beast that alone is more complex than many other things combined. When working on it, it would be useful to only run the relevant tests without having to manually count testcase numbers.
I don't expect other single functions getting their own category.
If you still prefer to put it somewhere else I can do that, too.
OK, I can understand, it makes sense to some extents. And I agree that if we'd ever extend printf it would be needed to extend these tests. Then let's leave it that way.
Thanks, Willy