libelf_allocate.c revision 302408 
1/*-
2 * Copyright (c) 2006,2008,2010 Joseph Koshy
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27/*
28 * Internal APIs
29 */
30
31#include <assert.h>
32#include <errno.h>
33#include <libelf.h>
34#include <stdlib.h>
35#include <string.h>
36
37#include "_libelf.h"
38
39ELFTC_VCSID("$Id: libelf_allocate.c 3174 2015-03-27 17:13:41Z emaste $");
40
41Elf *
42_libelf_allocate_elf(void)
43{
44	Elf *e;
45
46	if ((e = malloc(sizeof(*e))) == NULL) {
47		LIBELF_SET_ERROR(RESOURCE, errno);
48		return NULL;
49	}
50
51	e->e_activations = 1;
52	e->e_hdr.e_rawhdr = NULL;
53	e->e_byteorder   = ELFDATANONE;
54	e->e_class       = ELFCLASSNONE;
55	e->e_cmd         = ELF_C_NULL;
56	e->e_fd          = -1;
57	e->e_flags	 = 0;
58	e->e_kind        = ELF_K_NONE;
59	e->e_parent      = NULL;
60	e->e_rawfile     = NULL;
61	e->e_rawsize     = 0;
62	e->e_version     = LIBELF_PRIVATE(version);
63
64	(void) memset(&e->e_u, 0, sizeof(e->e_u));
65
66	return (e);
67}
68
69void
70_libelf_init_elf(Elf *e, Elf_Kind kind)
71{
72	assert(e != NULL);
73	assert(e->e_kind == ELF_K_NONE);
74
75	e->e_kind = kind;
76
77	switch (kind) {
78	case ELF_K_ELF:
79		STAILQ_INIT(&e->e_u.e_elf.e_scn);
80		break;
81	default:
82		break;
83	}
84}
85
86#define	FREE(P)		do {				\
87		if (P)					\
88			free(P);			\
89	} while (0)
90
91
92Elf *
93_libelf_release_elf(Elf *e)
94{
95	Elf_Arhdr *arh;
96
97	switch (e->e_kind) {
98	case ELF_K_AR:
99		FREE(e->e_u.e_ar.e_symtab);
100		break;
101
102	case ELF_K_ELF:
103		switch (e->e_class) {
104		case ELFCLASS32:
105			FREE(e->e_u.e_elf.e_ehdr.e_ehdr32);
106			FREE(e->e_u.e_elf.e_phdr.e_phdr32);
107			break;
108		case ELFCLASS64:
109			FREE(e->e_u.e_elf.e_ehdr.e_ehdr64);
110			FREE(e->e_u.e_elf.e_phdr.e_phdr64);
111			break;
112		}
113
114		assert(STAILQ_EMPTY(&e->e_u.e_elf.e_scn));
115
116		if (e->e_flags & LIBELF_F_AR_HEADER) {
117			arh = e->e_hdr.e_arhdr;
118			FREE(arh->ar_name);
119			FREE(arh->ar_rawname);
120			free(arh);
121		}
122
123		break;
124
125	default:
126		break;
127	}
128
129	free(e);
130
131	return (NULL);
132}
133
134struct _Libelf_Data *
135_libelf_allocate_data(Elf_Scn *s)
136{
137	struct _Libelf_Data *d;
138
139	if ((d = calloc((size_t) 1, sizeof(*d))) == NULL) {
140		LIBELF_SET_ERROR(RESOURCE, 0);
141		return (NULL);
142	}
143
144	d->d_scn = s;
145
146	return (d);
147}
148
149struct _Libelf_Data *
150_libelf_release_data(struct _Libelf_Data *d)
151{
152
153	if (d->d_flags & LIBELF_F_DATA_MALLOCED)
154		free(d->d_data.d_buf);
155
156	free(d);
157
158	return (NULL);
159}
160
161Elf_Scn *
162_libelf_allocate_scn(Elf *e, size_t ndx)
163{
164	Elf_Scn *s;
165
166	if ((s = calloc((size_t) 1, sizeof(Elf_Scn))) == NULL) {
167		LIBELF_SET_ERROR(RESOURCE, errno);
168		return (NULL);
169	}
170
171	s->s_elf = e;
172	s->s_ndx = ndx;
173
174	STAILQ_INIT(&s->s_data);
175	STAILQ_INIT(&s->s_rawdata);
176
177	STAILQ_INSERT_TAIL(&e->e_u.e_elf.e_scn, s, s_next);
178
179	return (s);
180}
181
182Elf_Scn *
183_libelf_release_scn(Elf_Scn *s)
184{
185	Elf *e;
186	struct _Libelf_Data *d, *td;
187
188	assert(s != NULL);
189
190	STAILQ_FOREACH_SAFE(d, &s->s_data, d_next, td) {
191		STAILQ_REMOVE(&s->s_data, d, _Libelf_Data, d_next);
192		d = _libelf_release_data(d);
193	}
194
195	STAILQ_FOREACH_SAFE(d, &s->s_rawdata, d_next, td) {
196		assert((d->d_flags & LIBELF_F_DATA_MALLOCED) == 0);
197		STAILQ_REMOVE(&s->s_rawdata, d, _Libelf_Data, d_next);
198		d = _libelf_release_data(d);
199	}
200
201	e = s->s_elf;
202
203	assert(e != NULL);
204
205	STAILQ_REMOVE(&e->e_u.e_elf.e_scn, s, _Elf_Scn, s_next);
206
207	free(s);
208
209	return (NULL);
210}
211