root/usr/src/lib/libdtrace/common/dlink_init.c
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 2012 by Delphix. All rights reserved.
 */

/*
 * This is the basis for drti.o which dt_link.c links into the object file
 * generated by dtrace(8) -G by default (note that -xlazyload disables this).
 */

#include <dlfcn.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>

#include <dlink.h>

static int gen;                 /* DOF helper generation */
extern dof_hdr_t __SUNW_dof;    /* DOF defined in the .SUNW_dof section */

#pragma init(dtrace_drti_init)
static void
dtrace_drti_init(void)
{
        Link_map *lmp;
        Lmid_t lmid;

        dtrace_link_init();

        if (dlinfo(RTLD_SELF, RTLD_DI_LINKMAP, &lmp) == -1 || lmp == NULL) {
                dl_dprintf(1, "couldn't discover module name or address\n");
                return;
        }

        if (dlinfo(RTLD_SELF, RTLD_DI_LMID, &lmid) == -1) {
                dl_dprintf(1, "couldn't discover link map ID\n");
                return;
        }

        dtrace_link_dof(&__SUNW_dof, lmid, lmp->l_name, lmp->l_addr);
}

#pragma fini(dtrace_drti_fini)
static void
dtrace_drti_fini(void)
{
        int fd;

        if ((fd = open64(devname, O_RDWR)) < 0) {
                dl_dprintf(1, "failed to open helper device %s", devname);
                return;
        }

        if ((gen = ioctl(fd, DTRACEHIOC_REMOVE, gen)) == -1)
                dl_dprintf(1, "DTrace ioctl failed to remove DOF (%d)\n", gen);
        else
                dl_dprintf(1, "DTrace ioctl removed DOF (%d)\n", gen);

        (void) close(fd);
}