Re: [PATCH v2] git-compat-util: undefine fileno if defined

On Tue, Feb 12, 2019 at 8:45 PM Duy Nguyen [off-list ref] wrote:

On Fri, Feb 08, 2019 at 08:36:21PM -0600, Dan McGregor wrote:

quoted

Commit 8dd2e88a92 ("http: support file handles for HTTP_KEEP_ERROR",
2019-01-10) introduced an implicit assumption that rewind, fileno, and
fflush are functions. At least on FreeBSD fileno is not, and as such
passing a void * failed.

All systems tested (FreeBSD and NetBSD) that define fineo as a macro

OpenBSD or NetBSD? From this [1], it looks like OpenBSD fails while
NetBSD compiles ok (and fails to run some tests)

According to this [2] looks like NetBSD is affected too, but only in
no-thread mode. With pthreads, fileno is not redefined as a macro.
That probably explains why it's ok from git-ci.

#define fileno(p) __sfileno(p)

#define __sfileno(p) \
    ((p)->_file == -1 ? -1 : (int)(unsigned short)(p)->_file)

[2] http://cvsweb.netbsd.org/bsdweb.cgi/src/include/stdio.h?rev=1.97&content-type=text/x-cvsweb-markup

For the record, at least fbsd also defines feof, ferror, clearerr,
getc and putc in the same way. But at least I don't see how something
like feof(fp++) could cause bad side effects.

... and __sfileno (and other friends) can cause bad side effects,
sigh. It's probably best to avoid fancy function calls.
-- 
Duy