1 files changed, 232 insertions, 0 deletions
diff --git a/libs/libaxolotl/src/vpool.c b/libs/libaxolotl/src/vpool.c
new file mode 100644
index 0000000000..97b4ec8dd4
--- /dev/null
+++ b/libs/libaxolotl/src/vpool.c
@@ -0,0 +1,232 @@
+/*
+ * 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 <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "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)
+{
+	char *ret;
+	size_t size;
+	int error;
+
+	error = vpool_new_size(pool, datsize, &size);
+	if (error != 0)
+		return (error);
+
+	if (size > pool->v_size) {
+		ret = (char *) 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) -
+	    (size_t)((char*)pool->v_buf - (char*)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)
+{
+	char *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 = (char *)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)
+{
+	char *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 = (char *)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 = (char *)pool->v_buf + size;
+		} else {
+			memmove((char *)pool->v_buf + where,
+			    (char *)pool->v_buf + where + size,
+			    pool->v_off - size - where);
+		}
+		pool->v_off -= size;
+	} else {
+		pool->v_buf = (char*)(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;
+}