libelf_allocate.c revision 260697 
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 <sys/cdefs.h>
32
33#include <assert.h>
34#include <errno.h>
35#include <libelf.h>
36#include <stdlib.h>
37#include <string.h>
38
39#include "_libelf.h"
40
41ELFTC_VCSID("$Id: libelf_allocate.c 2272 2011-12-03 17:07:31Z jkoshy $");
42
43Elf *
44_libelf_allocate_elf(void)
45{
46	Elf *e;
47
48	if ((e = malloc(sizeof(*e))) == NULL) {
49		LIBELF_SET_ERROR(RESOURCE, errno);
50		return NULL;
51	}
52
53	e->e_activations = 1;
54	e->e_hdr.e_rawhdr = NULL;
55	e->e_byteorder   = ELFDATANONE;
56	e->e_class       = ELFCLASSNONE;
57	e->e_cmd         = ELF_C_NULL;
58	e->e_fd          = -1;
59	e->e_flags	 = 0;
60	e->e_kind        = ELF_K_NONE;
61	e->e_parent      = NULL;
62	e->e_rawfile     = NULL;
63	e->e_rawsize     = 0;
64	e->e_version     = LIBELF_PRIVATE(version);
65
66	(void) memset(&e->e_u, 0, sizeof(e->e_u));
67
68	return (e);
69}
70
71void
72_libelf_init_elf(Elf *e, Elf_Kind kind)
73{
74	assert(e != NULL);
75	assert(e->e_kind == ELF_K_NONE);
76
77	e->e_kind = kind;
78
79	switch (kind) {
80	case ELF_K_ELF:
81		STAILQ_INIT(&e->e_u.e_elf.e_scn);
82		break;
83	default:
84		break;
85	}
86}
87
88#define	FREE(P)		do {				\
89		if (P)					\
90			free(P);			\
91	} while (0)
92
93
94Elf *
95_libelf_release_elf(Elf *e)
96{
97	Elf_Arhdr *arh;
98
99	switch (e->e_kind) {
100	case ELF_K_AR:
101		FREE(e->e_u.e_ar.e_symtab);
102		break;
103
104	case ELF_K_ELF:
105		switch (e->e_class) {
106		case ELFCLASS32:
107			FREE(e->e_u.e_elf.e_ehdr.e_ehdr32);
108			FREE(e->e_u.e_elf.e_phdr.e_phdr32);
109			break;
110		case ELFCLASS64:
111			FREE(e->e_u.e_elf.e_ehdr.e_ehdr64);
112			FREE(e->e_u.e_elf.e_phdr.e_phdr64);
113			break;
114		}
115
116		assert(STAILQ_EMPTY(&e->e_u.e_elf.e_scn));
117
118		if (e->e_flags & LIBELF_F_AR_HEADER) {
119			arh = e->e_hdr.e_arhdr;
120			FREE(arh->ar_name);
121			FREE(arh->ar_rawname);
122			free(arh);
123		}
124
125		break;
126
127	default:
128		break;
129	}
130
131	free(e);
132
133	return (NULL);
134}
135
136struct _Libelf_Data *
137_libelf_allocate_data(Elf_Scn *s)
138{
139	struct _Libelf_Data *d;
140
141	if ((d = calloc((size_t) 1, sizeof(*d))) == NULL) {
142		LIBELF_SET_ERROR(RESOURCE, 0);
143		return (NULL);
144	}
145
146	d->d_scn = s;
147
148	return (d);
149}
150
151struct _Libelf_Data *
152_libelf_release_data(struct _Libelf_Data *d)
153{
154
155	if (d->d_flags & LIBELF_F_DATA_MALLOCED)
156		free(d->d_data.d_buf);
157
158	free(d);
159
160	return (NULL);
161}
162
163Elf_Scn *
164_libelf_allocate_scn(Elf *e, size_t ndx)
165{
166	Elf_Scn *s;
167
168	if ((s = calloc((size_t) 1, sizeof(Elf_Scn))) == NULL) {
169		LIBELF_SET_ERROR(RESOURCE, errno);
170		return (NULL);
171	}
172
173	s->s_elf = e;
174	s->s_ndx = ndx;
175
176	STAILQ_INIT(&s->s_data);
177	STAILQ_INIT(&s->s_rawdata);
178
179	STAILQ_INSERT_TAIL(&e->e_u.e_elf.e_scn, s, s_next);
180
181	return (s);
182}
183
184Elf_Scn *
185_libelf_release_scn(Elf_Scn *s)
186{
187	Elf *e;
188	struct _Libelf_Data *d, *td;
189
190	assert(s != NULL);
191
192	STAILQ_FOREACH_SAFE(d, &s->s_data, d_next, td) {
193		STAILQ_REMOVE(&s->s_data, d, _Libelf_Data, d_next);
194		d = _libelf_release_data(d);
195	}
196
197	STAILQ_FOREACH_SAFE(d, &s->s_rawdata, d_next, td) {
198		assert((d->d_flags & LIBELF_F_DATA_MALLOCED) == 0);
199		STAILQ_REMOVE(&s->s_rawdata, d, _Libelf_Data, d_next);
200		d = _libelf_release_data(d);
201	}
202
203	e = s->s_elf;
204
205	assert(e != NULL);
206
207	STAILQ_REMOVE(&e->e_u.e_elf.e_scn, s, _Elf_Scn, s_next);
208
209	free(s);
210
211	return (NULL);
212}
213