1.\" Copyright (c) 2006,2008 Joseph Koshy. All rights reserved. 2.\" 3.\" Redistribution and use in source and binary forms, with or without 4.\" modification, are permitted provided that the following conditions 5.\" are met: 6.\" 1. Redistributions of source code must retain the above copyright 7.\" notice, this list of conditions and the following disclaimer. 8.\" 2. Redistributions in binary form must reproduce the above copyright 9.\" notice, this list of conditions and the following disclaimer in the 10.\" documentation and/or other materials provided with the distribution. 11.\" 12.\" This software is provided by Joseph Koshy ``as is'' and 13.\" any express or implied warranties, including, but not limited to, the 14.\" implied warranties of merchantability and fitness for a particular purpose 15.\" are disclaimed. in no event shall Joseph Koshy be liable 16.\" for any direct, indirect, incidental, special, exemplary, or consequential 17.\" damages (including, but not limited to, procurement of substitute goods 18.\" or services; loss of use, data, or profits; or business interruption) 19.\" however caused and on any theory of liability, whether in contract, strict 20.\" liability, or tort (including negligence or otherwise) arising in any way 21.\" out of the use of this software, even if advised of the possibility of 22.\" such damage. 23.\" 24.\" $Id: gelf_getrel.3 3734 2019-04-22 14:10:49Z jkoshy $ 25.\" 26.Dd April 22, 2019 27.Dt GELF_GETREL 3 28.Os 29.Sh NAME 30.Nm gelf_getrel , 31.Nm gelf_update_rel 32.Nd read and update ELF relocation entries 33.Sh LIBRARY 34.Lb libelf 35.Sh SYNOPSIS 36.In gelf.h 37.Ft "GElf_Rel *" 38.Fn gelf_getrel "Elf_Data *data" "int ndx" "GElf_Rel *rel" 39.Ft int 40.Fn gelf_update_rel "Elf_Data *data" "int ndx" "GElf_Rel *rel" 41.Sh DESCRIPTION 42These convenience functions are used to retrieve and update class-dependent 43.Vt Elf32_Rel 44or 45.Vt Elf64_Rel 46structures in an ELF object. 47.Pp 48Argument 49.Ar data 50is an 51.Vt Elf_Data 52descriptor associated with a section of type 53.Dv SHT_REL . 54Argument 55.Ar ndx 56is the index of the entry being retrieved or updated. 57The class-independent 58.Vt GElf_Rel 59structure is described in 60.Xr gelf 3 . 61.Pp 62Function 63.Fn gelf_getrel 64retrieves the class-dependent entry at index 65.Ar ndx 66in data buffer 67.Ar data 68and copies it to the destination pointed to by argument 69.Ar rel 70after translation to class-independent form. 71.Pp 72Function 73.Fn gelf_update_rel 74converts the class-independent entry pointed to 75by argument 76.Ar rel 77to class-dependent form, and writes it to the entry at index 78.Ar ndx 79in the data buffer described by argument 80.Ar data . 81Function 82.Fn gelf_update_rel 83signals an error if any of the values in the class-independent 84representation exceeds the representable limits of the target 85type. 86.Sh RETURN VALUES 87Function 88.Fn gelf_getrel 89returns the value of argument 90.Ar rel 91if successful, or NULL in case of an error. 92Function 93.Fn gelf_update_rel 94returns a non-zero value if successful, or zero in case of an error. 95.Sh ERRORS 96These functions may fail with the following errors: 97.Bl -tag -width "[ELF_E_RESOURCE]" 98.It Bq Er ELF_E_ARGUMENT 99Arguments 100.Ar data 101or 102.Ar rel 103were NULL. 104.It Bq Er ELF_E_ARGUMENT 105Argument 106.Ar ndx 107was less than zero or larger than the number of entries in the data 108descriptor. 109.It Bq Er ELF_E_ARGUMENT 110Data descriptor 111.Ar data 112was not associated with a section of type 113.Dv SHT_REL . 114.It Bq Er ELF_E_RANGE 115A value was not representable in the target type. 116.It Bq Er ELF_E_VERSION 117The 118.Vt Elf_Data 119descriptor denoted by argument 120.Ar data 121is associated with an ELF object with an unsupported version. 122.El 123.Sh SEE ALSO 124.Xr elf 3 , 125.Xr elf_getdata 3 , 126.Xr elf_getscn 3 , 127.Xr gelf 3 128