libelf/common/error.c

	error.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * 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 2001-2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"    /* SVr4.0 1.16  */


#pragma weak    elf_errmsg = _elf_errmsg
#pragma weak    elf_errno = _elf_errno

#include    "syn.h"
#include    <thread.h>
#include    <stdlib.h>
#include    <string.h>
#include    <stdio.h>
#include    <libelf.h>
#include    "msg.h"
#include    "decl.h"

#define ELFERRSHIFT 16
#define SYSERRMASK  0xffff


/*
 * _elf_err has two values encoded in it, both the _elf_err # and
 * the system errno value (if relevant).  These values are encoded
 * in the upper & lower 16 bits of the 4 byte integer.
 */
static int      _elf_err = 0;

static mutex_t      keylock;
static mutex_t      buflock;
static thread_key_t errkey;
static thread_key_t bufkey;
static int      keyonce = 0;
static int      bufonce = 0;
NOTE(DATA_READABLE_WITHOUT_LOCK(keyonce))
NOTE(DATA_READABLE_WITHOUT_LOCK(bufonce))


extern char *_dgettext(const char *, const char *);


const char *
_libelf_msg(Msg mid)
{
    return (_dgettext(MSG_ORIG(MSG_SUNW_OST_SGS), MSG_ORIG(mid)));
}


void
_elf_seterr(Msg lib_err, int sys_err)
{
    /*LINTED*/
    intptr_t encerr = ((int)lib_err << ELFERRSHIFT) |
        (sys_err & SYSERRMASK);

#ifndef __lock_lint
    if (thr_main()) {
        _elf_err = (int)encerr;
        return;
    }
#endif
    if (keyonce == 0) {
        (void) mutex_lock(&keylock);
        if (keyonce == 0) {
            (void) thr_keycreate(&errkey, 0);
            keyonce++;
        }
        (void) mutex_unlock(&keylock);
    }

    (void) thr_setspecific(errkey, (void *)encerr);
}

int
_elf_geterr() {
    intptr_t    rc;

#ifndef __lock_lint
    if (thr_main())
        return (_elf_err);
#endif
    if (keyonce == 0)
        return (0);

    (void) thr_getspecific(errkey, (void **)(&rc));
    return ((int)rc);
}

const char *
elf_errmsg(int err)
{
    char            *errno_str;
    char            *elferr_str;
    char            *buffer = 0;
    int         syserr;
    int         elferr;
    static char     intbuf[MAXELFERR];

    if (err == 0) {
        if ((err = _elf_geterr()) == 0)
            return (0);
    } else if (err == -1) {
        if ((err = _elf_geterr()) == 0)
            /*LINTED*/ /* MSG_INTL(EINF_NULLERROR) */
            err = (int)EINF_NULLERROR << ELFERRSHIFT;
    }

    if (thr_main())
        buffer = intbuf;
    else {
        /*
         * If this is a threaded APP then we store the
         * errmsg buffer in Thread Specific Storage.
         *
         * Each thread has its own private buffer.
         */
        if (bufonce == 0) {
            (void) mutex_lock(&buflock);
            if (bufonce == 0) {
                if (thr_keycreate(&bufkey, free) != 0) {
                    (void) mutex_unlock(&buflock);
                    return (MSG_INTL(EBUG_THRDKEY));
                }
                bufonce++;
            }
            (void) mutex_unlock(&buflock);
        }

        (void) thr_getspecific(bufkey, (void **)&buffer);

        if (!buffer) {
            if ((buffer = malloc(MAXELFERR)) == 0)
                return (MSG_INTL(EMEM_ERRMSG));
            if (thr_setspecific(bufkey, buffer) != 0) {
                free(buffer);
                return (MSG_INTL(EBUG_THRDSET));
            }
        }
    }

    elferr = (int)((uint_t)err >> ELFERRSHIFT);
    syserr = err & SYSERRMASK;
    /*LINTED*/
    elferr_str = (char *)MSG_INTL(elferr);
    if (syserr && (errno_str = strerror(syserr)))
        (void) snprintf(buffer, MAXELFERR,
            MSG_ORIG(MSG_FMT_ERR), elferr_str, errno_str);
    else {
        (void) strncpy(buffer, elferr_str, MAXELFERR - 1);
        buffer[MAXELFERR - 1] = '\0';
    }

    return (buffer);
}

int
elf_errno()
{
    int rc = _elf_geterr();

    _elf_seterr(0, 0);
    return (rc);
}