[unix-history] / usr / src / sys.386bsd / kern / tty_ring.c

/*
 * Copyright (c) 1989, 1990, 1991, 1992 William F. Jolitz, TeleMuse
 * All rights reserved.
 *
 * 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 software is a component of "386BSD" developed by 
	William F. Jolitz, TeleMuse.
 * 4. Neither the name of the developer nor the name "386BSD"
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS A COMPONENT OF 386BSD DEVELOPED BY WILLIAM F. JOLITZ 
 * AND IS INTENDED FOR RESEARCH AND EDUCATIONAL PURPOSES ONLY. THIS 
 * SOFTWARE SHOULD NOT BE CONSIDERED TO BE A COMMERCIAL PRODUCT. 
 * THE DEVELOPER URGES THAT USERS WHO REQUIRE A COMMERCIAL PRODUCT 
 * NOT MAKE USE THIS WORK.
 *
 * FOR USERS WHO WISH TO UNDERSTAND THE 386BSD SYSTEM DEVELOPED
 * BY WILLIAM F. JOLITZ, WE RECOMMEND THE USER STUDY WRITTEN 
 * REFERENCES SUCH AS THE  "PORTING UNIX TO THE 386" SERIES 
 * (BEGINNING JANUARY 1991 "DR. DOBBS JOURNAL", USA AND BEGINNING 
 * JUNE 1991 "UNIX MAGAZIN", GERMANY) BY WILLIAM F. JOLITZ AND 
 * LYNNE GREER JOLITZ, AS WELL AS OTHER BOOKS ON UNIX AND THE 
 * ON-LINE 386BSD USER MANUAL BEFORE USE. A BOOK DISCUSSING THE INTERNALS 
 * OF 386BSD ENTITLED "386BSD FROM THE INSIDE OUT" WILL BE AVAILABLE LATE 1992.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPER ``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 DEVELOPER 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.
 *
 */
static char rcsid[] = "$Header: /usr/bill/working/sys/kern/RCS/tty_ring.c,v 1.2 92/01/21 21:29:55 william Exp $";

#include "param.h"
#include "systm.h"
#include "buf.h"
#include "ioctl.h"
#include "tty.h"

putc(c, rbp) struct ringb *rbp;
{
	char *nxtp;

	/* ring buffer full? */
	if ( (nxtp = RB_SUCC(rbp, rbp->rb_tl)) == rbp->rb_hd) return (-1);

	/* stuff character */
	*rbp->rb_tl = c;
	rbp->rb_tl = nxtp;
	return(0);
}

getc(rbp) struct ringb *rbp;
{
	u_char c;

	/* ring buffer empty? */
	if (rbp->rb_hd == rbp->rb_tl) return(-1);

	/* fetch character, locate next character */
	c = *(u_char *) rbp->rb_hd;
	rbp->rb_hd = RB_SUCC(rbp, rbp->rb_hd);
	return (c);
}

nextc(cpp, rbp) struct ringb *rbp; char **cpp; {

	if (*cpp == rbp->rb_tl) return (0);
	else {	char *cp;
		cp = *cpp;
		*cpp = RB_SUCC(rbp, cp);
		return(*cp);
	}
}

ungetc(c, rbp) struct ringb *rbp;
{
	char	*backp;

	/* ring buffer full? */
	if ( (backp = RB_PRED(rbp, rbp->rb_hd)) == rbp->rb_tl) return (-1);
	rbp->rb_hd = backp;

	/* stuff character */
	*rbp->rb_hd = c;
	return(0);
}

unputc(rbp) struct ringb *rbp;
{
	char	*backp;
	int c;

	/* ring buffer empty? */
	if (rbp->rb_hd == rbp->rb_tl) return(-1);

	/* backup buffer and dig out previous character */
	backp = RB_PRED(rbp, rbp->rb_tl);
	c = *(u_char *)backp;
	rbp->rb_tl = backp;

	return(c);
}

#define	peekc(rbp)	(*(rbp)->rb_hd)

initrb(rbp) struct ringb *rbp; {
	rbp->rb_hd = rbp->rb_tl = rbp->rb_buf;
}

/*
 * Example code for contiguous operations:
	...
	nc = RB_CONTIGPUT(&rb);
	if (nc) {
	if (nc > 9) nc = 9;
		bcopy("ABCDEFGHI", rb.rb_tl, nc);
		rb.rb_tl += nc;
		rb.rb_tl = RB_ROLLOVER(&rb, rb.rb_tl);
	}
	...
	...
	nc = RB_CONTIGGET(&rb);
	if (nc) {
		if (nc > 79) nc = 79;
		bcopy(rb.rb_hd, stringbuf, nc);
		rb.rb_hd += nc;
		rb.rb_hd = RB_ROLLOVER(&rb, rb.rb_hd);
		stringbuf[nc] = 0;
		printf("%s|", stringbuf);
	}
	...
 */

/*
 * Concatinate ring buffers.
 */
catb(from, to)
	struct ringb *from, *to;
{
	char c;

	while ((c = getc(from)) >= 0)
		putc(c, to);
}
Commit	Line	Data
d0968c4e WJ	1	/*
	2	* Copyright (c) 1989, 1990, 1991, 1992 William F. Jolitz, TeleMuse
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This software is a component of "386BSD" developed by
	16	William F. Jolitz, TeleMuse.
	17	* 4. Neither the name of the developer nor the name "386BSD"
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS A COMPONENT OF 386BSD DEVELOPED BY WILLIAM F. JOLITZ
	22	* AND IS INTENDED FOR RESEARCH AND EDUCATIONAL PURPOSES ONLY. THIS
	23	* SOFTWARE SHOULD NOT BE CONSIDERED TO BE A COMMERCIAL PRODUCT.
	24	* THE DEVELOPER URGES THAT USERS WHO REQUIRE A COMMERCIAL PRODUCT
	25	* NOT MAKE USE THIS WORK.
	26	*
	27	* FOR USERS WHO WISH TO UNDERSTAND THE 386BSD SYSTEM DEVELOPED
	28	* BY WILLIAM F. JOLITZ, WE RECOMMEND THE USER STUDY WRITTEN
	29	* REFERENCES SUCH AS THE "PORTING UNIX TO THE 386" SERIES
	30	* (BEGINNING JANUARY 1991 "DR. DOBBS JOURNAL", USA AND BEGINNING
	31	* JUNE 1991 "UNIX MAGAZIN", GERMANY) BY WILLIAM F. JOLITZ AND
	32	* LYNNE GREER JOLITZ, AS WELL AS OTHER BOOKS ON UNIX AND THE
	33	* ON-LINE 386BSD USER MANUAL BEFORE USE. A BOOK DISCUSSING THE INTERNALS
	34	* OF 386BSD ENTITLED "386BSD FROM THE INSIDE OUT" WILL BE AVAILABLE LATE 1992.
	35	*
	36	* THIS SOFTWARE IS PROVIDED BY THE DEVELOPER ``AS IS'' AND
	37	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	38	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	39	* ARE DISCLAIMED. IN NO EVENT SHALL THE DEVELOPER BE LIABLE
	40	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	41	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	42	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	43	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	44	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	45	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	46	* SUCH DAMAGE.
	47	*
	48	*/
	49	static char rcsid[] = "$Header: /usr/bill/working/sys/kern/RCS/tty_ring.c,v 1.2 92/01/21 21:29:55 william Exp $";
	50
	51	#include "param.h"
	52	#include "systm.h"
	53	#include "buf.h"
	54	#include "ioctl.h"
	55	#include "tty.h"
	56
	57	putc(c, rbp) struct ringb *rbp;
	58	{
	59	char *nxtp;
	60
	61	/* ring buffer full? */
	62	if ( (nxtp = RB_SUCC(rbp, rbp->rb_tl)) == rbp->rb_hd) return (-1);
	63
	64	/* stuff character */
65	*rbp->rb_tl = c;
66	rbp->rb_tl = nxtp;
67	return(0);
68	}
69
70	getc(rbp) struct ringb *rbp;
71	{
72	u_char c;
73
74	/* ring buffer empty? */
75	if (rbp->rb_hd == rbp->rb_tl) return(-1);
76
77	/* fetch character, locate next character */
78	c = (u_char ) rbp->rb_hd;
79	rbp->rb_hd = RB_SUCC(rbp, rbp->rb_hd);
80	return (c);
81	}
82
83	nextc(cpp, rbp) struct ringb rbp; char *cpp; {
84
85	if (*cpp == rbp->rb_tl) return (0);
86	else { char *cp;
87	cp = *cpp;
88	*cpp = RB_SUCC(rbp, cp);
89	return(*cp);
90	}
91	}
92
93	ungetc(c, rbp) struct ringb *rbp;
94	{
95	char *backp;
96
97	/* ring buffer full? */
98	if ( (backp = RB_PRED(rbp, rbp->rb_hd)) == rbp->rb_tl) return (-1);
99	rbp->rb_hd = backp;
100
101	/* stuff character */
102	*rbp->rb_hd = c;
103	return(0);
104	}
105
106	unputc(rbp) struct ringb *rbp;
107	{
108	char *backp;
109	int c;
110
111	/* ring buffer empty? */
112	if (rbp->rb_hd == rbp->rb_tl) return(-1);
113
114	/* backup buffer and dig out previous character */
115	backp = RB_PRED(rbp, rbp->rb_tl);
116	c = (u_char )backp;
117	rbp->rb_tl = backp;
118
119	return(c);
120	}
121
122	#define peekc(rbp) (*(rbp)->rb_hd)
123
124	initrb(rbp) struct ringb *rbp; {
125	rbp->rb_hd = rbp->rb_tl = rbp->rb_buf;
126	}
127
128	/*
129	* Example code for contiguous operations:
130	...
131	nc = RB_CONTIGPUT(&rb);
132	if (nc) {
133	if (nc > 9) nc = 9;
134	bcopy("ABCDEFGHI", rb.rb_tl, nc);
135	rb.rb_tl += nc;
136	rb.rb_tl = RB_ROLLOVER(&rb, rb.rb_tl);
137	}
138	...
139	...
140	nc = RB_CONTIGGET(&rb);
141	if (nc) {
142	if (nc > 79) nc = 79;
143	bcopy(rb.rb_hd, stringbuf, nc);
144	rb.rb_hd += nc;
145	rb.rb_hd = RB_ROLLOVER(&rb, rb.rb_hd);
146	stringbuf[nc] = 0;
147	printf("%s\|", stringbuf);
148	}
149	...
150	*/
151
152	/*
153	* Concatinate ring buffers.
154	*/
155	catb(from, to)
156	struct ringb from, to;
157	{
158	char c;
159
160	while ((c = getc(from)) >= 0)
161	putc(c, to);
162	}