/*      $NetBSD: elf_errmsg.c,v 1.5 2024/03/03 17:37:33 christos Exp $  */

/*-
* Copyright (c) 2006,2008,2011 Joseph Koshy
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>

#include <libelf.h>
#include <stdio.h>
#include <string.h>

#include "_libelf.h"

__RCSID("$NetBSD: elf_errmsg.c,v 1.5 2024/03/03 17:37:33 christos Exp $");
ELFTC_VCSID("Id: elf_errmsg.c 3977 2022-05-01 06:45:34Z jkoshy");

/*
* Retrieve a human readable translation for an error message.
*/

static const char *_libelf_errors[] = {
#define DEFINE_ERROR(N,S)       [ELF_E_##N] = S
       DEFINE_ERROR(NONE,      "No Error"),
       DEFINE_ERROR(ARCHIVE,   "Malformed ar(1) archive"),
       DEFINE_ERROR(ARGUMENT,  "Invalid argument"),
       DEFINE_ERROR(CLASS,     "ELF class mismatch"),
       DEFINE_ERROR(DATA,      "Invalid data buffer descriptor"),
       DEFINE_ERROR(HEADER,    "Missing or malformed ELF header"),
       DEFINE_ERROR(IO,        "I/O error"),
       DEFINE_ERROR(LAYOUT,    "Layout constraint violation"),
       DEFINE_ERROR(MODE,      "Incorrect ELF descriptor mode"),
       DEFINE_ERROR(RANGE,     "Value out of range of target"),
       DEFINE_ERROR(RESOURCE,  "Resource exhaustion"),
       DEFINE_ERROR(SECTION,   "Invalid section descriptor"),
       DEFINE_ERROR(SEQUENCE,  "API calls out of sequence"),
       DEFINE_ERROR(UNIMPL,    "Unimplemented feature"),
       DEFINE_ERROR(VERSION,   "Unknown ELF API version"),
       DEFINE_ERROR(NUM,       "Unknown error")
#undef  DEFINE_ERROR
};

const char *
elf_errmsg(int error)
{
       int oserr;

       if (error == ELF_E_NONE &&
           (error = LIBELF_PRIVATE(error)) == 0)
           return NULL;
       else if (error == -1)
           error = LIBELF_PRIVATE(error);

       oserr = error >> LIBELF_OS_ERROR_SHIFT;
       error &= LIBELF_ELF_ERROR_MASK;

       if (error < ELF_E_NONE || error >= ELF_E_NUM)
               return _libelf_errors[ELF_E_NUM];
       if (oserr) {
               (void) snprintf((char *) LIBELF_PRIVATE(msg),
                   sizeof(LIBELF_PRIVATE(msg)), "%s: %s",
                   _libelf_errors[error], strerror(oserr));
               return (const char *)&LIBELF_PRIVATE(msg);
       }
       return _libelf_errors[error];
}