freebsd-dev/sys/sys/cons.h
Peter Wemm f41325db5f With this commit, I hereby pronounce gensetdefs past its use-by date.
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible.  <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.

The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).

The macros declare a strongly typed set.  They return elements with the
type that you declare the set with, rather than a generic void *.

For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>).  Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.

For a.out, we use the old linker_set struct.

NOTE: the item lists are no longer null terminated.  This is why
the code impact is high in certain areas.

The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.

linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.

Reviewed by:	eivind
2001-06-13 10:58:39 +00:00

101 lines
3.8 KiB
C

/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)cons.h 7.2 (Berkeley) 5/9/91
* $FreeBSD$
*/
#ifndef _MACHINE_CONS_H_
#define _MACHINE_CONS_H_
struct consdev;
typedef void cn_probe_t __P((struct consdev *));
typedef void cn_init_t __P((struct consdev *));
typedef void cn_term_t __P((struct consdev *));
typedef int cn_getc_t __P((dev_t));
typedef int cn_checkc_t __P((dev_t));
typedef void cn_putc_t __P((dev_t, int));
typedef void cn_dbctl_t __P((dev_t, int));
struct consdev {
cn_probe_t *cn_probe;
/* probe hardware and fill in consdev info */
cn_init_t *cn_init;
/* turn on as console */
cn_term_t *cn_term;
/* turn off as console */
cn_getc_t *cn_getc;
/* kernel getchar interface */
cn_checkc_t *cn_checkc;
/* kernel "return char if available" interface */
cn_putc_t *cn_putc;
/* kernel putchar interface */
cn_dbctl_t *cn_dbctl;
/* debugger control interface */
struct tty *cn_tp; /* tty structure for console device */
dev_t cn_dev; /* major/minor of device */
short cn_pri; /* pecking order; the higher the better */
};
/* values for cn_pri - reflect our policy for console selection */
#define CN_DEAD 0 /* device doesn't exist */
#define CN_NORMAL 1 /* device exists but is nothing special */
#define CN_INTERNAL 2 /* "internal" bit-mapped display */
#define CN_REMOTE 3 /* serial interface with remote bit set */
#ifdef _KERNEL
extern int cons_unavail;
extern struct consdev *cn_tab;
#define CONS_DRIVER(name, probe, init, term, getc, checkc, putc, dbctl) \
static struct consdev name##_consdev = { \
probe, init, term, getc, checkc, putc, dbctl \
}; \
DATA_SET(cons_set, name##_consdev)
/* Other kernel entry points. */
int cncheckc __P((void));
int cngetc __P((void));
void cninit __P((void));
void cninit_finish __P((void));
void cndbctl __P((int));
void cnputc __P((int));
#endif /* _KERNEL */
#endif /* !_MACHINE_CONS_H_ */