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-rw-r--r--src/contrib/vpool/vpool.c241
1 files changed, 241 insertions, 0 deletions
diff --git a/src/contrib/vpool/vpool.c b/src/contrib/vpool/vpool.c
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+++ b/src/contrib/vpool/vpool.c
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+/*
+ * Copyright (c) 2006, 2008 Alexey Vatchenko <av@bsdua.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <errno.h>
+#include <limits.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "contrib/vpool/vpool.h"
+
+static void vpool_shift(struct vpool *pool);
+static int vpool_new_size(struct vpool *pool, size_t datsize,
+ size_t *size);
+static int vpool_resize(struct vpool *pool, size_t datsize);
+
+static void
+vpool_shift(struct vpool *pool)
+{
+ if (pool->v_buf != pool->v_basebuf) {
+ memmove(pool->v_basebuf, pool->v_buf, pool->v_off);
+ pool->v_buf = pool->v_basebuf;
+ }
+}
+
+static int
+vpool_new_size(struct vpool *pool, size_t datsize, size_t *size)
+{
+ size_t need;
+ size_t rem;
+
+ if (datsize <= pool->v_size - pool->v_off) {
+ *size = pool->v_size;
+ return (0);
+ }
+
+ /* Check limit of new requested size */
+ if (pool->v_limit - pool->v_off < datsize) {
+ return (EFBIG);
+ }
+ need = pool->v_off + datsize;
+
+ /* Check limit of new size aligned to block size */
+ rem = need % pool->v_blksize;
+ if (rem != 0) {
+ if (pool->v_limit - pool->v_off >=
+ datsize + (pool->v_blksize - rem)) {
+ need += pool->v_blksize - rem;
+ } else {
+ need = pool->v_limit;
+ }
+ }
+
+ *size = need;
+ return (0);
+}
+
+static int
+vpool_resize(struct vpool *pool, size_t datsize)
+{
+ void *ret;
+ size_t size;
+ int error;
+
+ error = vpool_new_size(pool, datsize, &size);
+ if (error != 0) {
+ return (error);
+ }
+
+ if (size > pool->v_size) {
+ ret = malloc(size);
+ if (ret == NULL) {
+ return (ENOMEM);
+ }
+
+ memcpy(ret, pool->v_buf, pool->v_off);
+ free(pool->v_basebuf);
+ pool->v_basebuf = pool->v_buf = ret;
+ pool->v_size = size;
+ } else if ((pool->v_size - pool->v_off) -
+ (pool->v_buf - pool->v_basebuf) < datsize) {
+ vpool_shift(pool);
+ }
+
+ return (0);
+}
+
+void
+vpool_init(struct vpool *pool, size_t blksize, size_t limit)
+{
+
+ pool->v_basebuf = pool->v_buf = NULL;
+ pool->v_off = pool->v_size = 0;
+
+ pool->v_blksize = (blksize == 0) ? 4096 : blksize; /* XXX */
+ pool->v_limit = (limit == 0) ? SIZE_MAX : limit;
+
+ pool->v_lasterr = 0;
+}
+
+void
+vpool_final(struct vpool *pool)
+{
+ free(pool->v_basebuf);
+}
+
+void
+vpool_reset(struct vpool *pool)
+{
+ free(pool->v_basebuf);
+ pool->v_basebuf = pool->v_buf = NULL;
+ pool->v_off = pool->v_size = 0;
+ pool->v_lasterr = 0;
+}
+
+void
+vpool_wipe(struct vpool *pool)
+{
+ pool->v_off = 0;
+ pool->v_lasterr = 0;
+}
+
+void *
+vpool_insert(struct vpool *pool, size_t where, void *data, size_t datsize)
+{
+ void *ret;
+ int error;
+
+ error = vpool_resize(pool, datsize);
+ if (error != 0) {
+ pool->v_lasterr = error;
+ return (NULL);
+ }
+
+ /*
+ * If ``where'' is greater than or equal to offset then
+ * we are appending data to the end of the buffer.
+ */
+ if (where > pool->v_off) {
+ where = pool->v_off;
+ }
+
+ ret = (uint8_t *)pool->v_buf + where;
+ if (pool->v_off - where > 0) {
+ memmove(ret + datsize, ret, pool->v_off - where);
+ }
+ memcpy(ret, data, datsize);
+ pool->v_off += datsize;
+ pool->v_lasterr = 0;
+
+ return (ret);
+}
+
+void *
+vpool_expand(struct vpool *pool, size_t where, size_t size)
+{
+ void *ret;
+ int error;
+
+ error = vpool_resize(pool, size);
+ if (error != 0) {
+ pool->v_lasterr = error;
+ return (NULL);
+ }
+
+ /*
+ * If ``where'' is greater than or equal to offset then
+ * we are appending data to the end of the buffer.
+ */
+ if (where > pool->v_off) {
+ where = pool->v_off;
+ }
+
+ ret = (uint8_t *)pool->v_buf + where;
+ if (pool->v_off - where > 0) {
+ memmove(ret + size, ret, pool->v_off - where);
+ }
+ pool->v_off += size;
+ pool->v_lasterr = 0;
+
+ return (ret);
+}
+
+int
+vpool_truncate(struct vpool *pool,
+ size_t where, size_t size, enum vpool_trunc how)
+{
+ /* Check if caller wants to remove more data than we have */
+ if (where >= pool->v_off ||
+ size > pool->v_off || pool->v_off - size < where) {
+ pool->v_lasterr = ERANGE;
+ return (pool->v_lasterr);
+ }
+
+ if (how == VPOOL_EXCLUDE) {
+ if (where == 0) {
+ /*
+ * Optimization.
+ * Don't move data, just adjust pointer.
+ */
+ pool->v_buf = (uint8_t *)pool->v_buf + size;
+ } else {
+ memmove((uint8_t *)pool->v_buf + where,
+ (uint8_t *)pool->v_buf + where + size,
+ pool->v_off - size - where);
+ }
+ pool->v_off -= size;
+ } else {
+ pool->v_buf = (uint8_t *)pool->v_buf + where;
+ pool->v_off = size;
+ }
+
+ pool->v_lasterr = 0;
+ return (0);
+}
+
+void
+vpool_export(struct vpool *pool, void **buf, size_t *size)
+{
+ vpool_shift(pool);
+ *buf = pool->v_buf;
+ *size = pool->v_off;
+ pool->v_basebuf = pool->v_buf = NULL;
+ pool->v_off = pool->v_size = 0;
+ pool->v_lasterr = 0;
+}