minix/lib/libc/asyn/asyn_cancel.c
David van Moolenbroek 9ba65d2ea8 This patch switches the MINIX3 ethernet driver stack from a port-based
model to an instance-based model. Each ethernet driver instance is now
responsible for exactly one network interface card. The port field in
/etc/inet.conf now acts as an instance field instead.

This patch also updates the data link protocol. This update:
- eliminates the concept of ports entirely;
- eliminates DL_GETNAME entirely;
- standardizes on using m_source for IPC and DL_ENDPT for safecopies;
- removes error codes from TASK/STAT replies, as they were unused;
- removes a number of other old or unused fields;
- names and renames a few other fields.

All ethernet drivers have been changed to:
- conform to the new protocol, and exactly that;
- take on an instance number based on a given "instance" argument;
- skip that number of PCI devices in probe iterations;
- use config tables and environment variables based on that number;
- no longer be limited to a predefined maximum of cards in any way;
- get rid of any leftover non-safecopy support and other ancient junk;
- have a correct banner protocol figure, or none at all.

Other changes:
* Inet.conf is now taken to be line-based, and supports #-comments.
  No existing installations are expected to be affected by this.
* A new, select-based asynchio library replaces the old one.
  Kindly contributed by Kees J. Bot.
* Inet now supports use of select() on IP devices.
  Combined, the last two changes together speed up dhcpd
  considerably in the presence of multiple interfaces.
* A small bug has been fixed in nonamed.
2010-05-17 22:22:53 +00:00

21 lines
537 B
C

/* asyn_cancel() - cancel an asynch operation Author: Kees J. Bot
* 7 Jul 1997
*/
#include "asyn.h"
int asyn_cancel(asynchio_t *asyn, int fd, int op)
/* Cancel an asynchronous operation if one is in progress. (This is easy with
* select(2), because no operation is actually happening.)
*/
{
asynfd_t *afd;
if ((unsigned) fd >= FD_SETSIZE) { errno= EBADF; return -1; }
afd= &asyn->asyn_afd[fd];
if (afd->afd_state[op] == WAITING) {
afd->afd_state[op]= IDLE;
FD_CLR(fd, &asyn->asyn_fdset[SEL_READ]);
}
return 0;
}