+++ /dev/null
-/*
- * This file is part of the Palacios Virtual Machine Monitor developed
- * by the V3VEE Project with funding from the United States National
- * Science Foundation and the Department of Energy.
- *
- * The V3VEE Project is a joint project between Northwestern University
- * and the University of New Mexico. You can find out more at
- * http://www.v3vee.org
- *
- * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
- * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
- * All rights reserved.
- *
- * Author: Jack Lange <jarusl@cs.northwestern.edu>
- *
- * This is free software. You are permitted to use,
- * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
- */
-
-#include <geekos/ring_buffer.h>
-#include <geekos/malloc.h>
-#include <geekos/ktypes.h>
-#include <geekos/debug.h>
-
-
-void init_ring_buffer(struct ring_buffer * ring, uint_t size) {
- ring->buf = Malloc(size);
- ring->size = size;
-
- ring->start = 0;
- ring->end = 0;
- ring->current_len = 0;
-}
-
-
-struct ring_buffer * create_ring_buffer(uint_t size) {
- struct ring_buffer * ring = (struct ring_buffer *)Malloc(sizeof(struct ring_buffer));
-
- init_ring_buffer(ring, size);
-
- return ring;
-}
-
-void free_ring_buffer(struct ring_buffer * ring) {
- Free(ring->buf);
- Free(ring);
-}
-
-
-
-
-
-static inline uchar_t * get_read_ptr(struct ring_buffer * ring) {
- return (uchar_t *)(ring->buf + ring->start);
-}
-
-static inline uchar_t * get_write_ptr(struct ring_buffer * ring) {
- return (uchar_t *)(ring->buf + ring->end);
-}
-
-
-static inline int get_read_section_size(struct ring_buffer * ring) {
- return ring->size - ring->start;
-}
-
-static inline int get_write_section_size(struct ring_buffer * ring) {
- return ring->size - ring->end;
-}
-
-static inline int is_read_loop(struct ring_buffer * ring, uint_t len) {
- if ((ring->start >= ring->end) && (ring->current_len > 0)) {
- // end is past the end of the buffer
- if (get_read_section_size(ring) < len) {
- return 1;
- }
- }
- return 0;
-}
-
-
-static inline int is_write_loop(struct ring_buffer * ring, uint_t len) {
- if ((ring->end >= ring->start) && (ring->current_len < ring->size)) {
- // end is past the end of the buffer
- if (get_write_section_size(ring) < len) {
- return 1;
- }
- }
- return 0;
-}
-
-
-int rb_data_len(struct ring_buffer * ring) {
- return ring->current_len;
-}
-
-int rb_capacity(struct ring_buffer * ring) {
- return ring->size;
-}
-
-int rb_read(struct ring_buffer * ring, char * dst, uint_t len) {
- int read_len = 0;
- int ring_data_len = ring->current_len;
-
- read_len = (len > ring_data_len) ? ring_data_len : len;
-
- if (is_read_loop(ring, read_len)) {
- int section_len = get_read_section_size(ring);
-
- memcpy(dst, get_read_ptr(ring), section_len);
- memcpy(dst + section_len, ring->buf, read_len - section_len);
-
- ring->start = read_len - section_len;
- } else {
- memcpy(dst, get_read_ptr(ring), read_len);
-
- ring->start += read_len;
- }
-
- ring->current_len -= read_len;
-
- return read_len;
-}
-
-
-
-
-int rb_peek(struct ring_buffer * ring, char * dst, uint_t len) {
- int read_len = 0;
- int ring_data_len = ring->current_len;
-
- read_len = (len > ring_data_len) ? ring_data_len : len;
-
- if (is_read_loop(ring, read_len)) {
- int section_len = get_read_section_size(ring);
-
- memcpy(dst, get_read_ptr(ring), section_len);
- memcpy(dst + section_len, ring->buf, read_len - section_len);
- } else {
- memcpy(dst, get_read_ptr(ring), read_len);
- }
-
- return read_len;
-}
-
-
-int rb_delete(struct ring_buffer * ring, uint_t len) {
- int del_len = 0;
- int ring_data_len = ring->current_len;
-
- del_len = (len > ring_data_len) ? ring_data_len : len;
-
- if (is_read_loop(ring, del_len)) {
- int section_len = get_read_section_size(ring);
- ring->start = del_len - section_len;
- } else {
- ring->start += del_len;
- }
-
- ring->current_len -= del_len;
- return del_len;
-}
-
-
-int rb_write(struct ring_buffer * ring, char * src, uint_t len) {
- int write_len = 0;
- int ring_avail_space = ring->size - ring->current_len;
-
- write_len = (len > ring_avail_space) ? ring_avail_space : len;
-
-
- if (is_write_loop(ring, write_len)) {
- int section_len = get_write_section_size(ring);
-
- memcpy(get_write_ptr(ring), src, section_len);
- ring->end = 0;
-
- memcpy(get_write_ptr(ring), src + section_len, write_len - section_len);
-
- ring->end += write_len - section_len;
- } else {
- memcpy(get_write_ptr(ring), src, write_len);
-
- ring->end += write_len;
- }
-
- ring->current_len += write_len;
-
- return write_len;
-}
-
-
-void print_ring_buffer(struct ring_buffer * ring) {
- int ctr = 0;
-
- for (ctr = 0; ctr < ring->current_len; ctr++) {
- int index = (ctr + ring->start) % ring->size;
-
- PrintBoth("Entry %d (index=%d): %c\n", ctr, index, ring->buf[index]);
- }
-}