1*0a6a1f1dSLionel Sambuc /* $NetBSD: elf_begin.c,v 1.2 2014/03/09 16:58:04 christos Exp $ */
2*0a6a1f1dSLionel Sambuc
3*0a6a1f1dSLionel Sambuc /*-
4*0a6a1f1dSLionel Sambuc * Copyright (c) 2006,2008-2011 Joseph Koshy
5*0a6a1f1dSLionel Sambuc * All rights reserved.
6*0a6a1f1dSLionel Sambuc *
7*0a6a1f1dSLionel Sambuc * Redistribution and use in source and binary forms, with or without
8*0a6a1f1dSLionel Sambuc * modification, are permitted provided that the following conditions
9*0a6a1f1dSLionel Sambuc * are met:
10*0a6a1f1dSLionel Sambuc * 1. Redistributions of source code must retain the above copyright
11*0a6a1f1dSLionel Sambuc * notice, this list of conditions and the following disclaimer.
12*0a6a1f1dSLionel Sambuc * 2. Redistributions in binary form must reproduce the above copyright
13*0a6a1f1dSLionel Sambuc * notice, this list of conditions and the following disclaimer in the
14*0a6a1f1dSLionel Sambuc * documentation and/or other materials provided with the distribution.
15*0a6a1f1dSLionel Sambuc *
16*0a6a1f1dSLionel Sambuc * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17*0a6a1f1dSLionel Sambuc * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18*0a6a1f1dSLionel Sambuc * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19*0a6a1f1dSLionel Sambuc * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20*0a6a1f1dSLionel Sambuc * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21*0a6a1f1dSLionel Sambuc * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22*0a6a1f1dSLionel Sambuc * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23*0a6a1f1dSLionel Sambuc * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24*0a6a1f1dSLionel Sambuc * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25*0a6a1f1dSLionel Sambuc * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26*0a6a1f1dSLionel Sambuc * SUCH DAMAGE.
27*0a6a1f1dSLionel Sambuc */
28*0a6a1f1dSLionel Sambuc
29*0a6a1f1dSLionel Sambuc #include <libelf.h>
30*0a6a1f1dSLionel Sambuc
31*0a6a1f1dSLionel Sambuc #include "_libelf.h"
32*0a6a1f1dSLionel Sambuc
33*0a6a1f1dSLionel Sambuc __RCSID("$NetBSD: elf_begin.c,v 1.2 2014/03/09 16:58:04 christos Exp $");
34*0a6a1f1dSLionel Sambuc ELFTC_VCSID("Id: elf_begin.c 2364 2011-12-28 17:55:25Z jkoshy ");
35*0a6a1f1dSLionel Sambuc
36*0a6a1f1dSLionel Sambuc Elf *
elf_begin(int fd,Elf_Cmd c,Elf * a)37*0a6a1f1dSLionel Sambuc elf_begin(int fd, Elf_Cmd c, Elf *a)
38*0a6a1f1dSLionel Sambuc {
39*0a6a1f1dSLionel Sambuc Elf *e;
40*0a6a1f1dSLionel Sambuc
41*0a6a1f1dSLionel Sambuc e = NULL;
42*0a6a1f1dSLionel Sambuc
43*0a6a1f1dSLionel Sambuc if (LIBELF_PRIVATE(version) == EV_NONE) {
44*0a6a1f1dSLionel Sambuc LIBELF_SET_ERROR(SEQUENCE, 0);
45*0a6a1f1dSLionel Sambuc return (NULL);
46*0a6a1f1dSLionel Sambuc }
47*0a6a1f1dSLionel Sambuc
48*0a6a1f1dSLionel Sambuc switch (c) {
49*0a6a1f1dSLionel Sambuc case ELF_C_NULL:
50*0a6a1f1dSLionel Sambuc return (NULL);
51*0a6a1f1dSLionel Sambuc
52*0a6a1f1dSLionel Sambuc case ELF_C_WRITE:
53*0a6a1f1dSLionel Sambuc /*
54*0a6a1f1dSLionel Sambuc * The ELF_C_WRITE command is required to ignore the
55*0a6a1f1dSLionel Sambuc * descriptor passed in.
56*0a6a1f1dSLionel Sambuc */
57*0a6a1f1dSLionel Sambuc a = NULL;
58*0a6a1f1dSLionel Sambuc break;
59*0a6a1f1dSLionel Sambuc
60*0a6a1f1dSLionel Sambuc case ELF_C_RDWR:
61*0a6a1f1dSLionel Sambuc if (a != NULL) { /* not allowed for ar(1) archives. */
62*0a6a1f1dSLionel Sambuc LIBELF_SET_ERROR(ARGUMENT, 0);
63*0a6a1f1dSLionel Sambuc return (NULL);
64*0a6a1f1dSLionel Sambuc }
65*0a6a1f1dSLionel Sambuc /*FALLTHROUGH*/
66*0a6a1f1dSLionel Sambuc case ELF_C_READ:
67*0a6a1f1dSLionel Sambuc /*
68*0a6a1f1dSLionel Sambuc * Descriptor `a' could be for a regular ELF file, or
69*0a6a1f1dSLionel Sambuc * for an ar(1) archive. If descriptor `a' was opened
70*0a6a1f1dSLionel Sambuc * using a valid file descriptor, we need to check if
71*0a6a1f1dSLionel Sambuc * the passed in `fd' value matches the original one.
72*0a6a1f1dSLionel Sambuc */
73*0a6a1f1dSLionel Sambuc if (a &&
74*0a6a1f1dSLionel Sambuc ((a->e_fd != -1 && a->e_fd != fd) || c != a->e_cmd)) {
75*0a6a1f1dSLionel Sambuc LIBELF_SET_ERROR(ARGUMENT, 0);
76*0a6a1f1dSLionel Sambuc return (NULL);
77*0a6a1f1dSLionel Sambuc }
78*0a6a1f1dSLionel Sambuc break;
79*0a6a1f1dSLionel Sambuc
80*0a6a1f1dSLionel Sambuc default:
81*0a6a1f1dSLionel Sambuc LIBELF_SET_ERROR(ARGUMENT, 0);
82*0a6a1f1dSLionel Sambuc return (NULL);
83*0a6a1f1dSLionel Sambuc
84*0a6a1f1dSLionel Sambuc }
85*0a6a1f1dSLionel Sambuc
86*0a6a1f1dSLionel Sambuc if (a == NULL)
87*0a6a1f1dSLionel Sambuc e = _libelf_open_object(fd, c, 1);
88*0a6a1f1dSLionel Sambuc else if (a->e_kind == ELF_K_AR)
89*0a6a1f1dSLionel Sambuc e = _libelf_ar_open_member(a->e_fd, c, a);
90*0a6a1f1dSLionel Sambuc else
91*0a6a1f1dSLionel Sambuc (e = a)->e_activations++;
92*0a6a1f1dSLionel Sambuc
93*0a6a1f1dSLionel Sambuc return (e);
94*0a6a1f1dSLionel Sambuc }
95