.\" Copyright (c) 2006-2008,2011 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: elf_flagdata.3,v 1.3 2020/05/18 06:46:23 jsg Exp $ .\" .Dd June 12, 2019 .Dt ELF_FLAGDATA 3 .Os .Sh NAME .Nm elf_flagarhdr , .Nm elf_flagdata , .Nm elf_flagehdr , .Nm elf_flagelf , .Nm elf_flagphdr , .Nm elf_flagscn , .Nm elf_flagshdr .Nd manipulate flags associated with ELF data structures .Sh LIBRARY .Lb libelf .Sh SYNOPSIS .In libelf.h .Ft "unsigned int" .Fn elf_flagarhdr "Elf_Arhdr *arhdr" "Elf_Cmd cmd" "unsigned int flags" .Ft "unsigned int" .Fn elf_flagdata "Elf_Data *data" "Elf_Cmd cmd" "unsigned int flags" .Ft "unsigned int" .Fn elf_flagehdr "Elf *elf" "Elf_Cmd cmd" "unsigned int flags" .Ft "unsigned int" .Fn elf_flagelf "Elf *elf" "Elf_Cmd cmd" "unsigned int flags" .Ft "unsigned int" .Fn elf_flagphdr "Elf *elf" "Elf_Cmd cmd" "unsigned int flags" .Ft "unsigned int" .Fn elf_flagscn "Elf_Scn *scn" "Elf_Cmd cmd" "unsigned int flags" .Ft "unsigned int" .Fn elf_flagshdr "Elf_Scn *scn" "Elf_Cmd cmd" "unsigned int flags" .Sh DESCRIPTION These functions are used to query, set or reset flags on data structures associated with an ELF file. .Pp Arguments .Ar arhdr , .Ar data , .Ar elf and .Ar scn denote the data structures whose flags need to be changed. These values should have been returned by prior calls to functions in the .Xr elf 3 API set: .Bl -bullet -compact .It Argument .Ar arhdr should have been returned by a prior call to .Xr elf_getarhdr 3 . .It Argument .Ar data should have been returned by a prior call to one of .Xr elf_newdata 3 , .Xr elf_getdata 3 or .Xr elf_rawdata 3 . .It Argument .Ar elf should have been allocated by a prior call to one of .Xr elf_begin 3 or .Xr elf_memory 3 . .It Argument .Ar scn should have been returned by a prior call to one of .Xr elf_getscn 3 , .Xr elf_newscn 3 or .Xr elf_nextscn 3 . .El These values are allowed to be NULL to simplify error handling in application code. .Pp Argument .Ar cmd may have the following values: .Bl -tag -width ELF_C_SET .It Dv ELF_C_CLR The argument .Ar flags specifies the flags to be cleared. .It Dv ELF_C_SET The argument .Ar flags specifies the flags to be set. .El .Pp The argument .Ar flags is allowed to have the following flags set: .Bl -tag -width ELF_F_ARCHIVE_SYSV .It Dv ELF_F_ARCHIVE This flag is only valid with the .Fn elf_flagelf API. It informs the library that the application desires to create an .Xr ar 1 archive. Argument .Ar elf should have been opened for writing using the .Dv ELF_C_WRITE command to function .Fn elf_begin . .It Dv ELF_F_ARCHIVE_SYSV This flag is used in conjunction with the .Dv ELF_F_ARCHIVE flag to indicate that library should create archives that conform to System V layout rules. The default is to create BSD style archives. .It Dv ELF_F_DIRTY Mark the associated data structure as needing to be written back to the underlying file. A subsequent call to .Xr elf_update 3 will resynchronize the library's internal data structures. .It Dv ELF_F_LAYOUT This flag is only valid with the .Fn elf_flagelf API. It informs the library that the application will take responsibility for the layout of the file and that the library is not to insert any padding in between sections. .El .Pp Marking a given data structure as .Dq dirty affects all of its contained elements. Thus marking an ELF descriptor .Ar elf with .Fn elf_flagelf "elf" "ELF_C_SET" "ELF_F_DIRTY" means that the entire contents of the descriptor are .Dq dirty . .Pp Using a value of zero for argument .Ar flags will return the current set of flags for the data structure being queried. .Sh RETURN VALUES These functions return the updated flags if successful, or zero if an error is detected. .Sh COMPATIBILITY The .Fn elf_flagarhdr function and the .Dv ELF_F_ARCHIVE and .Dv ELF_F_ARCHIVE_SYSV flags are an extension to the .Xr elf 3 API. .Sh ERRORS These functions may fail with the following errors: .Bl -tag -width "[ELF_E_RESOURCE]" .It Bq Er ELF_E_ARGUMENT An unsupported value was used for the .Ar cmd argument. .It Bq Er ELF_E_ARGUMENT Argument .Ar flags had unsupported flags set. .It Bq Er ELF_E_ARGUMENT The argument .Ar elf was not a descriptor for an ELF object. .It Bq Er ELF_E_MODE The .Dv ELF_F_ARCHIVE flag was used with an ELF descriptor that had not been opened for writing. .It Bq Er ELF_E_SEQUENCE Function .Fn elf_flagehdr was called without an executable header being allocated. .It Bq Er ELF_E_SEQUENCE Function .Fn elf_flagphdr was called without a program header being allocated. .El .Sh SEE ALSO .Xr elf 3 , .Xr elf32_newehdr 3 , .Xr elf32_newphdr 3 , .Xr elf64_newehdr 3 , .Xr elf64_newphdr 3 , .Xr elf_newdata 3 , .Xr elf_update 3 , .Xr gelf 3 , .Xr gelf_newehdr 3 , .Xr gelf_newphdr 3 , .Xr gelf_update_dyn 3 , .Xr gelf_update_move 3 , .Xr gelf_update_rel 3 , .Xr gelf_update_rela 3 , .Xr gelf_update_sym 3 , .Xr gelf_update_syminfo 3