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diff --git a/linkers/elftoolchain/libelf/gelf.3 b/linkers/elftoolchain/libelf/gelf.3 new file mode 100644 index 0000000..a5d68ce --- /dev/null +++ b/linkers/elftoolchain/libelf/gelf.3 @@ -0,0 +1,201 @@ +.\" Copyright (c) 2006,2008 Joseph Koshy. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" This software is provided by Joseph Koshy ``as is'' and +.\" any express or implied warranties, including, but not limited to, the +.\" implied warranties of merchantability and fitness for a particular purpose +.\" are disclaimed. in no event shall Joseph Koshy be liable +.\" for any direct, indirect, incidental, special, exemplary, or consequential +.\" damages (including, but not limited to, procurement of substitute goods +.\" or services; loss of use, data, or profits; or business interruption) +.\" however caused and on any theory of liability, whether in contract, strict +.\" liability, or tort (including negligence or otherwise) arising in any way +.\" out of the use of this software, even if advised of the possibility of +.\" such damage. +.\" +.\" $Id: gelf.3 189 2008-07-20 10:38:08Z jkoshy $ +.\" +.Dd September 1, 2006 +.Os +.Dt GELF 3 +.Sh NAME +.Nm GElf +.Nd class-independent API for ELF manipulation +.Sh LIBRARY +.Lb libelf +.Sh SYNOPSIS +.In gelf.h +.Sh DESCRIPTION +This manual page describes a class independent API for manipulating +ELF objects. +This API allows an application to operate on ELF descriptors without +needing to the know the ELF class of the descriptor. +.Pp +The GElf API may be used alongside the ELF API without restriction. +.Ss GElf Data Structures +The GElf API defines the following class-independent data structures: +.Bl -tag -width GElf_Sxword +.It Vt GElf_Addr +A representation of ELF addresses. +.It Vt GElf_Dyn +A class-independent representation of ELF +.Sy .dynamic +section entries. +.It Vt GElf_Ehdr +A class-independent representation of an ELF Executable Header. +.It Vt GElf_Half +An unsigned 16 bit quantity. +.It Vt GElf_Off +A class-independent representation of a ELF offset. +.It Vt GElf_Phdr +A class-independent representation of an ELF Program Header Table +entry. +.It Vt GElf_Rel +A class-independent representation of an ELF relocation entry. +.It Vt GElf_Rela +A class-independent representation of an ELF relocation entry with +addend. +.It Vt GElf_Shdr +A class-independent representation of an ELF Section Header Table +entry. +.It Vt GElf_Sword +A signed 32 bit quantity. +.It Vt GElf_Sxword +A signed 64 bit quantity. +.It Vt GElf_Sym +A class-independent representation of an ELF symbol table entry. +.It Vt GElf_Word +An unsigned 32 bit quantity. +.It Vt GElf_Xword +An unsigned 64 bit quantity. +.El +.Pp +These data structures are sized to be compatible with the +corresponding 64 bit ELF structures, and have the same internal +structure as their 64 bit class-dependent counterparts. +Class-dependent ELF structures are described in +.Xr elf 5 . +.Ss GElf Programming Model +GElf functions always return a +.Em copy +of the underlying (class-dependent) ELF data structure. +The programming model with GElf is as follows: +.Bl -enum +.It +An application will retrieve data from an ELF descriptor using a +.Fn gelf_get_* +function. +This will copy out data into a private +.Vt GElf_* +data structure. +.It +The application will work with its private copy of the GElf +structure. +.It +Once done, the application copies the new values back to the +underlying ELF data structure using the +.Fn gelf_update_* +functions. +.It +The application will then use the +.Fn elf_flag* +APIs to indicate to the ELF library that an ELF data structure is dirty. +.El +.Pp +When updating an underlying 32 bit ELF data structure, the GElf +routines will signal an error if a GElf value is out of range +for the underlying ELF data type. +.Ss Namespace use +The GElf interface uses the following symbols: +.Bl -tag +.It GElf_* +Class-independent data types. +.It gelf_* +For functions defined in the API set. +.El +.Ss GElf Programming APIs +This section provides an overview of the GElf programming APIs. +Further information is provided in the manual page of each function +listed here. +.Bl -tag +.It "Allocating ELF Data Structures" +.Bl -tag -compact +.It Fn gelf_newehdr +Allocate a new ELF Executable Header. +.It Fn gelf_newphdr +Allocate a new ELF Program Header Table. +.El +.It "Data Translation" +.Bl -tag -compact +.It Fn gelf_xlatetof +Translate the native representation of an ELF data structure to its +file representation. +.It Fn gelf_xlatetom +Translate from the file representation of an ELF data structure to a +native representation. +.El +.It "Retrieving ELF Data" +.Bl -tag -compact +.It Fn gelf_getdyn +Retrieve an ELF +.Sy .dynamic +table entry. +.It Fn gelf_getehdr +Retrieve an ELF Executable Header from the underlying ELF descriptor. +.It Fn gelf_getphdr +Retrieve an ELF Program Header Table entry from the underlying ELF descriptor. +.It Fn gelf_getrel +Retrieve an ELF relocation entry. +.It Fn gelf_getrela +Retrieve an ELF relocation entry with addend. +.It Fn gelf_getshdr +Retrieve an ELF Section Header Table entry from the underlying ELF descriptor. +.It Fn gelf_getsym +Retrieve an ELF symbol table entry. +.El +.It Queries +.Bl -tag -compact +.It Fn gelf_checksum +Retrieves the ELF checksum for an ELF descriptor. +.It Fn gelf_fsize +Retrieves the size of the file representation of an ELF type. +.It Fn gelf_getclass +Retrieves the ELF class of an ELF descriptor. +.El +.It "Updating ELF Data" +.Bl -tag -compact -width ".Fn gelf_update_shdr" +.It Fn gelf_update_dyn +Copy back an ELF +.Sy .dynamic +Table entry. +.It Fn gelf_update_phdr +Copy back an ELF Program Header Table entry. +.It Fn gelf_update_rel +Copy back an ELF relocation entry. +.It Fn gelf_update_rela +Copy back an ELF relocation with addend entry. +.It Fn gelf_update_shdr +Copy back an ELF Section Header Table entry. +.It Fn gelf_update_sym +Copy back an ELF symbol table entry. +.El +.El +.Sh SEE ALSO +.Xr elf 3 , +.Xr elf 5 +.Sh HISTORY +The GELF(3) API first appeared in System V Release 4. +This implementation of the API first appeared in +.Fx 7.0 . +.Sh AUTHORS +The GElf API was implemented by +.An "Joseph Koshy" +.Aq jkoshy@FreeBSD.org . |