On 25/09/15 19:29, Robert Millan wrote:
El 25/09/15 a les 00:10, Antti Kantee ha escrit:
Let me put it this way: the sys/soundcard.h that libossaudio installs
redefines ioctl so that it catches the ioctl calls before they go hit
the kernel. How does that work with a stock soundcard.h from
somewhere else? Is there some indirection in your stack somewhere
that I'm not aware of?
No indirection, it's simpler than that!
Take for example:
switch (com) {
case SNDCTL_DSP_RESET:
retval = ioctl(fd, AUDIO_FLUSH, 0);
if (retval < 0)
return retval;
break;
ossaudio.c is built using system-wide <sys/soundcard.h>. In turn, the ioctl
constant definitions in <sys/soundcard.h> use the system-wide _IOC macros.
At the same time, ossaudio.c is built using the NetBSD version of
sys/audioio.h,
which in turn uses _IOC macros by the NetBSD version of sys/ioccom.h [1].
The reason I'm trying to find alternate solutions is that I find
manually sprinkling ifdefs into the switch quite ugly and fragile and
would rather see a cleaner solution. Another way to work around that
problem is figure out how to use some sort of translator before the
switch so that the primary code path doesn't get polluted with ifdefs
... or to find someone who's not bothered by ifdefs to commit your
patch :/
Are you concerned with all ifdefs or just with the ones that get inside
"if () {}" statements? I think the later could possibly be replaced with
ifndef/define before the switch. Does this look better to you?
