Files
QNX/lib/c/support/_devctl.c
2025-08-20 19:02:58 +08:00

62 lines
1.8 KiB
C

/*
* $QNXLicenseC:
* Copyright 2007, QNX Software Systems. All Rights Reserved.
*
* You must obtain a written license from and pay applicable license fees to QNX
* Software Systems before you may reproduce, modify or distribute this software,
* or any work that includes all or part of this software. Free development
* licenses are available for evaluation and non-commercial purposes. For more
* information visit http://licensing.qnx.com or email licensing@qnx.com.
*
* This file may contain contributions from others. Please review this entire
* file for other proprietary rights or license notices, as well as the QNX
* Development Suite License Guide at http://licensing.qnx.com/license-guide/
* for other information.
* $
*/
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <devctl.h>
#include <sys/iomsg.h>
int _devctl(int fd, int dcmd, void *data_ptr, size_t nbytes, unsigned flags) {
io_devctl_t msg;
iov_t iov[4];
int (*send)(int, const struct iovec *, int, const struct iovec *, int);
// Stuff the message.
msg.i.type = _IO_DEVCTL;
msg.i.combine_len = sizeof msg.i;
msg.i.dcmd = dcmd;
msg.i.nbytes = nbytes;
msg.i.zero = 0;
// Setup data to the device.
SETIOV(iov + 0, &msg.i, sizeof msg.i);
SETIOV(iov + 1, data_ptr, (dcmd & DEVDIR_TO) ? nbytes : 0);
// Setup data from the device.
SETIOV(iov + 2, &msg.o, sizeof msg.o);
SETIOV(iov + 3, data_ptr, (dcmd & DEVDIR_FROM) ? nbytes : 0);
if(flags & _DEVCTL_FLAG_NOCANCEL) {
send = MsgSendvnc;
} else {
send = MsgSendv;
}
if(send(fd, iov + 0, 2, iov + 2, 2) == -1) {
if((flags & _DEVCTL_FLAG_NOTTY) && errno == ENOSYS) {
errno = ENOTTY;
}
return -1;
}
return (flags & _DEVCTL_FLAG_NORETVAL) ? 0 : msg.o.ret_val;
}
__SRCVERSION("_devctl.c $Rev: 153052 $");