rtld/amd64/dlamd64getunwind.c

	dlamd64getunwind.c revision 7257d1b4d25bfac0c802847390e98a464fd787ac
/*
 * 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.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * Block comment which describes the contents of this file.
 */

#include <string.h>
#include <dlfcn.h>
#include <debug.h>
#include <_rtld.h>
#include <_elf.h>
#include <msg.h>

#include <stdio.h>

static Dl_amd64_unwindinfo *
getunwind_core(Lm_list *lml, void *pc, Dl_amd64_unwindinfo *unwindinfo)
{
    Rt_map  *lmp;

    /*
     * Validate the version information.
     */
    if (unwindinfo == NULL) {
        eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLVAL));
        return (0);
    }
    if ((unwindinfo->dlui_version < DLUI_VERS_1) ||
        (unwindinfo->dlui_version > DLUI_VERS_CURRENT)) {
        eprintf(lml, ERR_FATAL, MSG_INTL(MSG_UNW_BADVERS),
            unwindinfo->dlui_version, DLUI_VERS_CURRENT);
        return (0);
    }

    /*
     * Clean out the structure.
     */
    unwindinfo->dlui_flags = 0;
    unwindinfo->dlui_objname = 0;
    unwindinfo->dlui_unwindstart = 0;
    unwindinfo->dlui_unwindend = 0;
    unwindinfo->dlui_segstart = 0;
    unwindinfo->dlui_segend = 0;

    /*
     * Identify the link-map associated with the exception "pc".  Note,
     * the "pc" might not correspond to a link-map (as can happen with a
     * "pc" fabricated by a debugger such as dbx).  In this case, the
     * unwind data buffer will be filled with flags set to indicate an
     * unknown caller.
     */
    lmp = _caller(pc, CL_NONE);

    if (lmp) {
        Mmap    *immap;

        unwindinfo->dlui_objname = PATHNAME(lmp);

        /*
         * Scan through the mmaps of this object to get the specific
         * segment found.
         */
        for (immap = MMAPS(lmp); immap->m_vaddr; immap++) {
            if (((caddr_t)pc >= immap->m_vaddr) &&
                ((caddr_t)pc < (immap->m_vaddr + immap->m_msize))) {
                break;
            }
        }
        unwindinfo->dlui_segstart = immap->m_vaddr;
        unwindinfo->dlui_segend = immap->m_vaddr + immap->m_msize;

        if (PTUNWIND(lmp) && (immap->m_vaddr)) {
            uintptr_t   base;

            if (FLAGS(lmp) & FLG_RT_FIXED)
                base = 0;
            else
                base = ADDR(lmp);

            unwindinfo->dlui_unwindstart =
                (void *)(PTUNWIND(lmp)->p_vaddr + base);
            unwindinfo->dlui_unwindend =
                (void *)(PTUNWIND(lmp)->p_vaddr +
                PTUNWIND(lmp)->p_memsz + base);

        } else if (immap->m_vaddr)
            unwindinfo->dlui_flags |= DLUI_FLG_NOUNWIND;
        else
            unwindinfo->dlui_flags |=
                DLUI_FLG_NOUNWIND | DLUI_FLG_NOOBJ;
    } else {
        /*
         * No object found.
         */
        unwindinfo->dlui_flags = DLUI_FLG_NOOBJ | DLUI_FLG_NOUNWIND;
    }
    return (unwindinfo);
}

#pragma weak _dlamd64getunwind = dlamd64getunwind

Dl_amd64_unwindinfo *
dlamd64getunwind(void *pc, Dl_amd64_unwindinfo *unwindinfo)
{
    Rt_map  *lmp;
    Lm_list *lml;
    int entry = enter(0);

    lmp = _caller(caller(), CL_EXECDEF);
    lml = LIST(lmp);

    unwindinfo = getunwind_core(lml, pc, unwindinfo);

    if (entry)
        leave(lml, 0);
    return (unwindinfo);
}