2 * Copyright (c) 1994, David Greenman
4 * Copyright (c) 2003-2011 The DragonFly Project. All rights reserved.
6 * This code is derived from software contributed to The DragonFly Project
7 * by Matthew Dillon <dillon@backplane.com>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice unmodified, this list of conditions, and the following
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * clist support routines
35 * The clist now contains two linear buffers c_quote and c_info, sized
36 * to c_cbmax. The caller must hold a lock or token specific to the clist
39 #include <sys/param.h>
40 #include <sys/kernel.h>
41 #include <sys/systm.h>
42 #include <sys/malloc.h>
46 * Allocate or reallocate clist buffers.
49 clist_alloc_cblocks(struct clist *cl, int ccmax)
55 if (ccmax == cl->c_ccmax)
58 clist_free_cblocks(cl);
61 data = kmalloc(ccmax * sizeof(*data), M_TTYS, M_INTWAIT|M_ZERO);
62 /* NOTE: cl fields may now be different due to blocking */
68 n = cl->c_ccmax - cl->c_cchead;
71 bcopy(cl->c_data + cl->c_cchead, data, n * sizeof(*data));
73 bcopy(cl->c_data, data + n,
74 (count - n) * sizeof(*data));
84 * Free the clist's buffer.
87 clist_free_cblocks(struct clist *cl)
103 * Get a character from the head of a clist.
106 clist_getc(struct clist *cl)
115 if (++i == cl->c_ccmax)
123 * Copy data from the clist to the destination linear buffer.
124 * Return the number of characters actually copied.
127 clist_qtob(struct clist *cl, char *dest, int n)
140 if (++i == cl->c_ccmax)
152 * Flush characters from the head of the clist, deleting them.
155 ndflush(struct clist *cl, int n)
161 i = cl->c_cchead + n;
162 if (i >= cl->c_ccmax)
169 * Append a character to the clist, return 0 on success, -1 if
170 * there is no room. The character can be quoted by setting TTY_QUOTE.
173 clist_putc(int c, struct clist *cl)
177 if (cl->c_cc == cl->c_ccmax)
179 i = cl->c_cchead + cl->c_cc;
180 if (i >= cl->c_ccmax)
182 cl->c_data[i] = (short)c & (TTY_QUOTE | TTY_CHARMASK);
189 * Copy data from linear buffer to clist chain. Return the
190 * number of characters not copied. The data will be flagged
191 * as not being quoted.
194 clist_btoq(char *src, int n, struct clist *cl)
200 count = cl->c_ccmax - cl->c_cc; /* space available */
202 count = n; /* count = bytes to copy */
203 remain = n - count; /* remain = bytes not copied */
205 i = cl->c_cchead + cl->c_cc; /* clist write index */
206 if (i >= cl->c_ccmax)
210 cl->c_data[i] = (short)(uint8_t)*src;
211 if (++i == cl->c_ccmax)
216 cl->c_cc += n - remain; /* bytes actually copied */
218 return remain; /* return bytes not copied */
222 * Get the next character in the clist relative to cp. If cp is NULL
223 * returns the first character in the clist. The character is stored in
224 * *dst. No clist pointers are advanced or adjusted.
226 * The returned pointer can be used as an iterator but should not be
227 * directly dereferenced.
230 clist_nextc(struct clist *cl, void *cp, int *dst)
239 cp = &cl->c_data[cl->c_cchead];
240 *dst = (uint16_t)*(short *)cp; /* can be quoted */
245 * Use i to calculate the next logical index to determine if
246 * there are any characters remaining.
248 i = (short *)cp - cl->c_data;
249 if (i < cl->c_cchead)
250 i += cl->c_ccmax - cl->c_cchead;
253 if (i + 1 == cl->c_cc) { /* no more chars */
259 * We can just use cp to iterate the next actual buffer
262 cp = (short *)cp + 1; /* next char (use pointer) */
263 if (cp == &cl->c_data[cl->c_ccmax])
265 *dst = (uint16_t)*(short *)cp;
271 * "Unput" a character from a clist, returning it.
274 clist_unputc(struct clist *cl)
282 i = cl->c_cchead + cl->c_cc;
283 if (i >= cl->c_ccmax)
285 c = (int)(uint16_t)cl->c_data[i];
291 * Move characters in source clist to destination clist,
292 * preserving quote bits. Non-critical path.
295 clist_catq(struct clist *cls, struct clist *cld)
299 while ((c = clist_getc(cls)) != -1)