xref: /titanic_50/usr/src/cmd/sgs/libelf/common/getphnum.c (revision 0a1278f26ea4b7c8c0285d4f2d6c5b680904aa01)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <string.h>
27 #include <gelf.h>
28 #include <decl.h>
29 #include <msg.h>
30 
31 /*
32  * Return number of entries in the program header array, taking
33  * extended headers into account.
34  *
35  * elf_getphnum() was defined based on the definition of the earlier
36  * elf_getshnum(). It returns 0 for failure, and 1 for success.
37  *
38  * elf_getphdrnum() supercedes elf_getphnum(), which is now considered
39  * obsolete. It returns -1 for failure and 0 for success, matching
40  * elf_getshdrnum(), and bringing us into alignment with the interface
41  * agreed to in the 2002 gABI meeting.
42  *
43  * See the comment in getshnum.c for additional information.
44  */
45 
46 int
47 elf_getphdrnum(Elf *elf, size_t *phnum)
48 {
49 	GElf_Ehdr	ehdr;
50 	Elf_Scn		*scn;
51 	GElf_Shdr	shdr0;
52 
53 	if (gelf_getehdr(elf, &ehdr) == NULL)
54 		return (-1);
55 
56 	if (ehdr.e_phnum != PN_XNUM) {
57 		*phnum = ehdr.e_phnum;
58 		return (0);
59 	}
60 
61 	if ((scn = elf_getscn(elf, 0)) == NULL ||
62 	    gelf_getshdr(scn, &shdr0) == NULL)
63 		return (-1);
64 
65 	if (shdr0.sh_info == 0)
66 		*phnum = ehdr.e_phnum;
67 	else
68 		*phnum = shdr0.sh_info;
69 
70 	return (0);
71 }
72 
73 int
74 elf_getphnum(Elf *elf, size_t *phnum)
75 {
76 	return (elf_getphdrnum(elf, phnum) == 0);
77 }
78