On 8/7/14 5:58 PM, Branko Čibej wrote:
> I've seen platforms where size_t was smaller than ptrdiff_t; but usually
> they're the same size. The rules of type promotion in C state that an a value
> of a signed type can be promoted to a value of the same-sized unsigned type
> without truncation, whereas the opposite is not true. That's why you don't get
> warnings here on most usual platforms. But the unusual platforms where size_t
> is smaller than ptrdiff_t could be a problem.
I'm not going signed -> unsigned. I'm going unsigned -> signed (specifically
apr_size_t to ptrdiff_t).
Specifically:
[[[
svn_error_t *
svn_x509_parse_cert(svn_x509_certinfo_t **certinfo,
const char *buf,
apr_size_t buflen,
apr_pool_t *result_pool,
apr_pool_t *scratch_pool)
{
svn_error_t *err;
ptrdiff_t len;
const unsigned char *p;
const unsigned char *end;
x509_cert *crt;
svn_x509_certinfo_t *ci;
svn_stringbuf_t *namebuf;
crt = apr_pcalloc(scratch_pool, sizeof(*crt));
p = (const unsigned char *)buf;
len = buflen;
end = p + len;
]]]
Note the next to last line where I assign the ptrdiff_t len with the value from
the apr_size_t buflen.
Unless I'm missing something that ought to be producing a warning should it not?
