[patch v1] stdio: Add more setvbuf tests

[DJ Delorie]

Joseph Myers <josmyers@redhat.com> writes:
>> +#include <dlfcn.h>
>
> What's <dlfcn.h> used for in this test?

Probably excess from cut-n-paste'ing headers and copyright from another
test.  Removed.

>> +/* Dear future developer: If you are reading this, you are likely
>> +   trying to change or understand this test.  In that case, these
>> +   debug/dump macros will be helpful.  */
>> +#if 0
>> +#define debug printf ("\033[3%dm%s:%d\033[0m\n", \
>
> Note the glibc style to use spaces after "#" for preprocessor directives 
> inside #if, so "# define" here.

Fixed.

>> +void
>> +prepare_test_data (void)
>> +{
>> +  buffer = (char *) malloc (bufsize);
>
> I'd expect a check for allocation failure (possibly through use of 
> xmalloc).  Maybe the code works even if allocation fails, but calling 
> setvbuf with a NULL buffer probably isn't testing the intended paths.

Fixed.

>> +	if (mknod (test_file_name, S_IFIFO | 0600, 0) != 0)
>> +	  FAIL_EXIT1 ("mknod: %m");
>
> This could use xmkfifo to avoid needing a local error check here.

Done.

>> +  switch (s)
>> +    {
>> +    case test_stream_stdin:
>> +      fp = fopen (fname, "r");
>> +      break;
>
> In this code, you're consistently not checking for a null fp until later:
>
> In particular, the above uses fileno (fp) before the check for not being 
> NULL.
>
> If interfaces such as xfopen can be used above, that would be the simplest 
> way to get early-enough error checks.

I switched to xfopen, but we don't have a corresponding xfdopen, so I
left the TEST_VERIFY_EXIT in.  I did move it before the ptmx code
though.

>> +	      if (s <= test_stream_stderr)
>> +		{
>> +		  rv += recurse (fp, f, s, c);
>> +		}
>> +	      else
>> +		{
>> +		  rv += do_second_part (fp, f, s, c);
>> +		}
>
> The normal style in glibc would be not to have braces around a single 
> expression statement like this.

Fixed.

V2 will be sent in a moment...