Lines Matching refs:ring
9 * usr/src/cmd/cmd-inet/usr.bin/telnet/ring.c
46 static char sccsid[] = "@(#)ring.c 8.1 (Berkeley) 6/6/93";
50 * This defines a structure for a ring buffer.
68 #include "ring.h"
85 * There is some trickiness here. Since the ring buffers are initialized
104 ring_init(ring, buffer, count)
105 Ring *ring;
109 (void) memset(ring, 0, sizeof (*ring));
111 ring->size = count;
113 ring->supply = ring->consume = ring->bottom = buffer;
115 ring->top = ring->bottom+ring->size;
117 ring->clearto = 0;
129 ring_mark(ring)
130 Ring *ring;
132 ring->mark = ring_decrement(ring, ring->supply, 1);
136 * Is the ring pointing to the mark?
140 ring_at_mark(ring)
141 Ring *ring;
143 if (ring->mark == ring->consume) {
151 * Clear any mark set on the ring.
155 ring_clear_mark(ring)
156 Ring *ring;
158 ring->mark = 0;
162 * Add characters from current segment to ring buffer.
165 ring_supplied(ring, count)
166 Ring *ring;
169 ring->supply = ring_increment(ring, ring->supply, count);
170 ring->supplytime = ++ring_clock;
177 ring_consumed(ring, count)
178 Ring *ring;
184 if (ring->mark &&
185 (ring_subtract(ring, ring->mark, ring->consume) < count)) {
186 ring->mark = 0;
189 if (ring->consume < ring->clearto &&
190 ring->clearto <= ring->consume + count)
191 ring->clearto = 0;
192 else if (ring->consume + count > ring->top &&
193 ring->bottom <= ring->clearto &&
194 ring->bottom + ((ring->consume + count) - ring->top))
195 ring->clearto = 0;
197 ring->consume = ring_increment(ring, ring->consume, count);
198 ring->consumetime = ++ring_clock;
202 if (ring_empty(ring)) {
203 ring->consume = ring->supply = ring->bottom;
214 ring_empty_count(ring)
215 Ring *ring;
217 if (ring_empty(ring)) { /* if empty */
218 return (ring->size);
220 return (ring_subtract(ring, ring->consume, ring->supply));
226 ring_empty_consecutive(ring)
227 Ring *ring;
229 if ((ring->consume < ring->supply) || ring_empty(ring)) {
234 return (ring_subtract(ring, ring->top, ring->supply));
239 return (ring_subtract(ring, ring->consume, ring->supply));
249 ring_full_count(ring)
250 Ring *ring;
252 if ((ring->mark == 0) || (ring->mark == ring->consume)) {
253 if (ring_full(ring)) {
254 return (ring->size); /* nothing consumed, but full */
256 return (ring_subtract(ring, ring->supply,
257 ring->consume));
260 return (ring_subtract(ring, ring->mark, ring->consume));
269 ring_full_consecutive(ring)
270 Ring *ring;
272 if ((ring->mark == 0) || (ring->mark == ring->consume)) {
273 if ((ring->supply < ring->consume) || ring_full(ring)) {
274 return (ring_subtract(ring, ring->top, ring->consume));
276 return (ring_subtract(ring, ring->supply,
277 ring->consume));
280 if (ring->mark < ring->consume) {
281 return (ring_subtract(ring, ring->top, ring->consume));
283 return (ring_subtract(ring, ring->mark, ring->consume));
289 * Move data into the "supply" portion of of the ring buffer.
292 ring_supply_data(ring, buffer, count)
293 Ring *ring;
300 i = MIN(count, ring_empty_consecutive(ring));
301 (void) memcpy(ring->supply, buffer, i);
302 ring_supplied(ring, i);
311 * Move data from the "consume" portion of the ring buffer
314 ring_consume_data(ring, buffer, count)
315 Ring *ring;
322 i = MIN(count, ring_full_consecutive(ring));
323 memcpy(buffer, ring->consume, i);
324 ring_consumed(ring, i);
332 ring_encrypt(ring, encryptor)
333 Ring *ring;
338 if (ring_empty(ring) || ring->clearto == ring->supply)
341 if ((c = ring->clearto) == NULL)
342 c = ring->consume;
344 s = ring->supply;
347 (*encryptor)(c, ring->top - c);
348 (*encryptor)(ring->bottom, s - ring->bottom);
352 ring->clearto = ring->supply;
356 ring_clearto(ring)
357 Ring *ring;
359 if (!ring_empty(ring))
360 ring->clearto = ring->supply;
362 ring->clearto = 0;