diff options
Diffstat (limited to 'src/VBox/ExtPacks/VBoxDTrace/onnv/lib/libdtrace/common/dt_buf.c')
| -rw-r--r-- | src/VBox/ExtPacks/VBoxDTrace/onnv/lib/libdtrace/common/dt_buf.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/src/VBox/ExtPacks/VBoxDTrace/onnv/lib/libdtrace/common/dt_buf.c b/src/VBox/ExtPacks/VBoxDTrace/onnv/lib/libdtrace/common/dt_buf.c new file mode 100644 index 00000000..e7b22bde --- /dev/null +++ b/src/VBox/ExtPacks/VBoxDTrace/onnv/lib/libdtrace/common/dt_buf.c @@ -0,0 +1,181 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License, Version 1.0 only + * (the "License"). You may not use this file except in compliance + * with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2005 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#ifndef VBOX +#pragma ident "%Z%%M% %I% %E% SMI" +#endif + +/* + * DTrace Memory Buffer Routines + * + * The routines in this file are used to create an automatically resizing + * memory buffer that can be written to like a file. Memory buffers are + * used to construct DOF to ioctl() to dtrace(7D), and provide semantics that + * simplify caller code. Specifically, any allocation errors result in an + * error code being set inside the buffer which is maintained persistently and + * propagates to another buffer if the buffer in error is concatenated. These + * semantics permit callers to execute a large series of writes without needing + * to check for errors and then perform a single check before using the buffer. + */ + +#ifndef VBOX +#include <sys/sysmacros.h> +#include <strings.h> +#endif + +#include <dt_impl.h> +#include <dt_buf.h> + +void +dt_buf_create(dtrace_hdl_t *dtp, dt_buf_t *bp, const char *name, size_t len) +{ + if (len == 0) + len = _dtrace_bufsize; + + bp->dbu_buf = bp->dbu_ptr = dt_zalloc(dtp, len); + bp->dbu_len = len; + + if (bp->dbu_buf == NULL) + bp->dbu_err = dtrace_errno(dtp); + else + bp->dbu_err = 0; + + bp->dbu_resizes = 0; + bp->dbu_name = name; +} + +void +dt_buf_destroy(dtrace_hdl_t *dtp, dt_buf_t *bp) +{ + dt_dprintf("dt_buf_destroy(%s): size=%lu resizes=%u\n", + bp->dbu_name, (ulong_t)bp->dbu_len, bp->dbu_resizes); + + dt_free(dtp, bp->dbu_buf); +} + +void +dt_buf_reset(dtrace_hdl_t *dtp, dt_buf_t *bp) +{ + if ((bp->dbu_ptr = bp->dbu_buf) != NULL) + bp->dbu_err = 0; + else + dt_buf_create(dtp, bp, bp->dbu_name, bp->dbu_len); +} + +void +dt_buf_write(dtrace_hdl_t *dtp, dt_buf_t *bp, + const void *buf, size_t len, size_t align) +{ + size_t off = (size_t)(bp->dbu_ptr - bp->dbu_buf); + size_t adj = roundup(off, align) - off; + + if (bp->dbu_err != 0) { + (void) dt_set_errno(dtp, bp->dbu_err); + return; /* write silently fails */ + } + + if (bp->dbu_ptr + adj + len > bp->dbu_buf + bp->dbu_len) { + size_t new_len = bp->dbu_len * 2; + uchar_t *new_buf; + uint_t r = 1; + + while (bp->dbu_ptr + adj + len > bp->dbu_buf + new_len) { + new_len *= 2; + r++; + } + + if ((new_buf = dt_zalloc(dtp, new_len)) == NULL) { + bp->dbu_err = dtrace_errno(dtp); + return; + } + + bcopy(bp->dbu_buf, new_buf, off); + dt_free(dtp, bp->dbu_buf); + + bp->dbu_buf = new_buf; + bp->dbu_ptr = new_buf + off; + bp->dbu_len = new_len; + bp->dbu_resizes += r; + } + + bp->dbu_ptr += adj; + bcopy(buf, bp->dbu_ptr, len); + bp->dbu_ptr += len; +} + +void +dt_buf_concat(dtrace_hdl_t *dtp, dt_buf_t *dst, + const dt_buf_t *src, size_t align) +{ + if (dst->dbu_err == 0 && src->dbu_err != 0) { + (void) dt_set_errno(dtp, src->dbu_err); + dst->dbu_err = src->dbu_err; + } else { + dt_buf_write(dtp, dst, src->dbu_buf, + (size_t)(src->dbu_ptr - src->dbu_buf), align); + } +} + +size_t +dt_buf_offset(const dt_buf_t *bp, size_t align) +{ + size_t off = (size_t)(bp->dbu_ptr - bp->dbu_buf); + return (roundup(off, align)); +} + +size_t +dt_buf_len(const dt_buf_t *bp) +{ + return (bp->dbu_ptr - bp->dbu_buf); +} + +int +dt_buf_error(const dt_buf_t *bp) +{ + return (bp->dbu_err); +} + +void * +dt_buf_ptr(const dt_buf_t *bp) +{ + return (bp->dbu_buf); +} + +void * +dt_buf_claim(dtrace_hdl_t *dtp, dt_buf_t *bp) +{ + void *buf = bp->dbu_buf; + + if (bp->dbu_err != 0) { + dt_free(dtp, buf); + buf = NULL; + } + + bp->dbu_buf = bp->dbu_ptr = NULL; + bp->dbu_len = 0; + + return (buf); +} |