glibc/elf/libelf.h
Roland McGrath 6e33fad374 Thu Apr 13 09:45:01 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* elf/libelf.h (elf_hash): Use XOR instead of ANDN when the bits
 	being cleared are already known to be set.  Thanks Ulrich.
1995-04-14 01:13:53 +00:00

284 lines
8.8 KiB
C

/* Interface for manipulating ELF object files; functions found in -lelf.
Copyright (C) 1995 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#ifndef _LIBELF_H
#define _LIBELF_H 1
#include <sys/cdefs.h>
#include <sys/types.h>
#include <elf.h>
__BEGIN_DECLS
/* Commands to operate on an Elf descriptor.
The meanings are slightly different for the different functions. */
typedef enum
{
ELF_C_NULL = 0,
ELF_C_READ, /* Read from the file. */
ELF_C_WRITE, /* Write the file, ignoring old contents. */
ELF_C_CLR, /* Clear specified flag bits. */
ELF_C_SET, /* Set specified flag bits. */
ELF_C_FDDONE, /* Close the fd; no further io will happen. */
ELF_C_FDREAD, /* Read the whole file, then close it. */
ELF_C_RDWR, /* Read from and modify the file. */
ELF_C_NUM /* Number of valid command values. */
} Elf_Cmd;
/* Flag bits for `elf_flag*'. */
#define ELF_F_DIRTY 0x1 /* Object is */
#define ELF_F_LAYOUT 0x4
/* File types. */
typedef enum
{
ELF_K_NONE = 0,
ELF_K_AR,
ELF_K_COFF, /* The GNU -lelf does not support COFF. */
ELF_K_ELF,
ELF_K_NUM /* Number of valid file kinds. */
} Elf_Kind;
/* Translation types. */
typedef enum
{
ELF_T_BYTE = 0,
ELF_T_ADDR,
ELF_T_DYN,
ELF_T_EHDR,
ELF_T_HALF,
ELF_T_OFF,
ELF_T_PHDR,
ELF_T_RELA,
ELF_T_REL,
ELF_T_SHDR,
ELF_T_SWORD,
ELF_T_SYM,
ELF_T_WORD,
ELF_T_NUM
} Elf_Type;
/* These types are opaque to user code; only pointers to them are used. */
typedef struct Elf Elf;
typedef struct Elf_Scn Elf_Scn;
/* Archive member header. */
typedef struct
{
char *ar_name;
time_t ar_date;
uid_t ar_uid;
gid_t ar_gid;
mode_t ar_mode;
off_t ar_size;
char *ar_rawname;
} Elf_Arhdr;
/* Archive symbol table. */
typedef struct
{
char *as_name;
size_t as_off;
unsigned long int as_hash;
} Elf_Arsym;
/* Data descriptor. */
typedef struct
{
void *d_buf;
Elf_Type d_type;
size_t d_size;
off_t d_off; /* Offset into section. */
size_t d_align; /* Alignment in section. */
unsigned int d_version; /* ELF version. */
} Elf_Data;
/* Open an Elf descriptor on file descriptor FD.
REF is the Elf descriptor for the containing archive (to open a member);
or the descriptor previously returned for FD (to add a user reference);
or NULL. */
extern Elf *elf_begin __P ((int __fd, Elf_Cmd __cmd, Elf *__ref));
/* Finish using ELF (remove a user reference); if this is the last user
reference, its data will be freed. */
extern int elf_end __P ((Elf *__elf));
/* Control the library's access to the file descriptor for ELF.
CMD is either ELF_C_FDDONE or ELF_C_FDREAD. */
extern int elf_cntl __P ((Elf *__elf, Elf_Cmd __cmd));
/* Return a string describing an ELF error number. */
extern __const char *elf_errmsg __P ((int __errno));
/* Return the ELF error number for the last failed operation. */
extern int elf_errno __P ((void));
/* Set the byte value used to fill sections for alignment. */
extern void elf_fill __P ((int __fillchar));
/* The following functions `elf_flag*' all operate the same way:
CMD is either ELF_C_SET or ELF_C_CLR; FLAGS are `ELF_F_*' above,
which are set or cleared for the object the call relates to. */
/* Modify flags affecting the file as a whole (?). */
extern unsigned int elf_flagelf __P ((Elf *__elf, Elf_Cmd __cmd,
unsigned int __flags));
/* Modify flags affecting DATA. */
extern unsigned int elf_flagdata __P ((Elf_Data *__data, Elf_Cmd __cmd,
unsigned int __flags));
/* Modify flags affecting the ELF header. */
extern unsigned int elf_flagehdr __P ((Elf *__elf, Elf_Cmd __cmd,
unsigned int __flags));
/* Modify flags affecting the ELF program header. */
extern unsigned int elf_flagphdr __P ((Elf *__elf, Elf_Cmd __cmd,
unsigned int __flags));
/* Modify flags affecting the given section's data. */
extern unsigned int elf_flagscn __P ((Elf_Scn *__scn, Elf_Cmd __cmd,
unsigned int __flags));
/* Modify flags affecting the given section's header. */
extern unsigned int elf_flagshdr __P ((Elf_Scn *__scn, Elf_Cmd __cmd,
unsigned int __flags));
extern size_t elf32_fsize __P ((Elf_Type __type, size_t __count,
unsigned int __ver));
/* Return the archive header for ELF, which must describe an archive. */
extern Elf_Arhdr *elf_getarhdr __P ((Elf *__elf));
/* Return the archive symbol table for ELF, and store
in *NELTSP the number of elements in the table. */
extern Elf_Arsym *elf_getarsym __P ((Elf *__elf, size_t *__neltsp));
/* Return the file offset for the beginning of ELF.
If ELF describes an archive member, this points to the member header. */
extern off_t elf_getbase __P ((Elf *__elf));
/* Extract the data from a section. */
extern Elf_Data *elf_getdata __P ((Elf_Scn *__scn, Elf_Data *__data));
/* Extract the ELF header from the file. */
extern Elf32_Ehdr *elf32_getehdr __P ((Elf *__elf));
/* Extract the initial ELF identification bytes from the file.
If PTR is nonnull, the number of identification bytes is stored there. */
extern char *elf_getident __P((Elf *__elf, size_t *__ptr));
/* Extract the ELF program header from the file. */
extern Elf32_Phdr *elf32_getphdr __P ((Elf *__elf));
/* Extract the indicated section from the file. */
extern Elf_Scn *elf_getscn __P ((Elf *__elf, size_t __index));
/* Extract the section header from the section. */
extern Elf32_Shdr *elf32_getshdr __P ((Elf_Scn *__scn));
/* Return the index of the section following SCN. */
extern size_t elf_ndxscn __P ((Elf_Scn *__scn));
/* Standard ELF symbol name hash function. */
extern unsigned long int elf_hash __P ((__const char *__name));
#if defined (__OPTIMIZE__) || defined (_EXTERN_INLINE)
#ifndef _EXTERN_INLINE
#define _EXTERN_INLINE extern __inline
#endif
_EXTERN_INLINE unsigned long int
elf_hash (__const char *__name)
{
/* This is the hashing function specified by the ELF ABI. */
unsigned long int __hash = 0;
while (*__name != '\0')
{
unsigned long int __hi;
__hash = (__hash << 4) + *__name++;
__hi = __hash & 0xf0000000;
if (__hi != 0)
{
__hash ^= __hi >> 24;
/* The ELF ABI says `hash &= ~hi', but this is equivalent
in this case and on some machines one insn instead of two. */
__hash ^= __hi;
}
}
return __hash;
}
#endif
/* Return the kind of file ELF describes. */
extern Elf_Kind elf_kind __P ((Elf *__elf));
extern Elf_Data *elf_newdata __P ((Elf_Scn *__scn));
/* Create the ELF header for ELF. */
extern Elf32_Ehdr *elf32_newehdr __P ((Elf *__elf));
/* Create the program header for ELF, with COUNT segments. */
extern Elf32_Phdr *elf32_newphdr __P ((Elf *__elf, size_t __count));
/* Create a new section in ELF. */
extern Elf_Scn *elf_newscn __P ((Elf *__elf));
/* Return the section following SCN. */
extern Elf_Scn *elf_nextscn __P ((Elf *__elf, Elf_Scn *__scn));
/* Set up ELF to read the next archive member. */
extern Elf_Cmd elf_next __P ((Elf *__elf));
/* Set up ELF (which must describe an archive) to read the
archive member that starts at file position OFFSET. */
extern size_t elf_rand __P ((Elf *__elf, size_t __offset));
extern Elf_Data *elf_rawdata __P ((Elf_Scn *__scn, Elf_Data *__data));
/* Read the entire file into memory; store its size in *PTR. */
extern char *elf_rawfile __P ((Elf *__elf, size_t *__ptr));
/* Return a pointer to the string at OFFSET bytes into the string table.
SECTION is the index of the SHT_STRTAB section in ELF. */
extern char *elf_strptr __P ((Elf *__elf, size_t __section, size_t __offset));
/* If CMD is ELF_C_NULL, update ELF's data structures based on any
user modifications, and set the ELF_F_DIRTY flag if anything changed.
If CMD is ELF_C_WRITE, do that and then write the changes to the file. */
extern off_t elf_update __P ((Elf *__elf, Elf_Cmd __cmd));
/* Handle ELF version VER. Return the old version handled,
or EV_NONE if VER is unrecognized. */
extern unsigned int elf_version __P ((unsigned int __ver));
extern Elf_Data *elf32_xlatetof __P ((Elf_Data *__dst, const Elf_Data *__src,
unsigned int __encode));
extern Elf_Data *elf32_xlatetom __P ((Elf_Data *__dst, const Elf_Data *__src,
unsigned int __encode));
__END_DECLS
#endif /* _LIBELF_H */