usr/src/cmd/sgs/libelf/common/getphnum.c

   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 }