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elf_xlate(S)


elf_xlate: elf32_xlatetof, elf32_xlatetom -- class-dependent data translation

Syntax

cc [flag . . . ] file . . . -lelf [library] . . .

#include <libelf.h>

Elf_Data *elf32_xlatetof(Elf_Data *dst, const Elf_Data *src, unsigned encode);

Elf_Data *elf32_xlatetom(Elf_Data *dst, const Elf_Data *src, unsigned encode);

Description


elf32_xlatetom(S) translates various data structures from their 32-bit class file representations to their memory representations; elf32_xlatetof(S) provides the inverse. This conversion is particularly important for cross-development environments.

src is a pointer to the source buffer that holds the original data; dst is a pointer to a destination buffer that will hold the translated copy. encode gives the byte encoding in which the file objects are (to be) represented. It must have one of the encoding values defined for the ELF header's e_ident[EI_DATA] entry (see elf_getident(S)).

If the data can be translated, the functions return dst. Otherwise, they return null because an error occurred, such as incompatible types, destination buffer overflow, and so forth.

elf_getdata(S) describes the Elf_Data descriptor, which the translation routines use as follows:


d_buf
Both the source and destination must have valid buffer pointers.

d_type
This member's value specifies the type of the data to which d_buf points and the type of data to be created in the destination. The program supplies a d_type value in the source; the library sets the destination's d_type() to the same value. These values are summarized below.

d_size
This member holds the total size, in bytes, of the memory occupied by the source data and the size allocated for the destination data. If the destination buffer is not large enough, the routines do not change its original contents. The translation routines reset the destination's d_size member to the actual size required, after the translation occurs. The source and destination sizes may differ.

d_version
This member holds the version number of the objects (desired) in the buffer. The source and destination versions are independent.

Translation routines allow the source and destination buffers to coincide. That is, dst->d_buf may equal src->d_buf. Other cases where the source and destination buffers overlap give undefined behavior.

Elf_Type 32-Bit Memory Type
ELF_T_ADDR Elf32_Addr
ELF_T_BYTE unsigned char
ELF_T_DYN Elf32_Dyn
ELF_T_EHDR Elf32_Ehdr
ELF_T_HALF Elf32_Half
ELT_T_OFF Elf32_Off
ELF_T_PHDR Elf32_Phdr
ELF_T_REL Elf32_Rel
ELF_T_RELA Elf32_Rela
ELF_T_SHDR Elf32_Shdr
ELF_T_SWORD Elf32_Sword
ELF_T_SYM Elf32_Sym
ELF_T_WORD Elf32_Word

 +-------------+--------------------+
 |Elf_Type     | 32-Bit Memory Type |
 +-------------+--------------------+
 |ELF_T_ADDR   | Elf32_Addr         |
 +-------------+--------------------+
 |ELF_T_BYTE   | unsigned char      |
 +-------------+--------------------+
 |ELF_T_DYN    | Elf32_Dyn          |
 +-------------+--------------------+
 |ELF_T_EHDR   | Elf32_Ehdr         |
 +-------------+--------------------+
 |ELF_T_HALF   | Elf32_Half         |
 +-------------+--------------------+
 |ELT_T_OFF    | Elf32_Off          |
 +-------------+--------------------+
 |ELF_T_PHDR   | Elf32_Phdr         |
 +-------------+--------------------+
 |ELF_T_REL    | Elf32_Rel          |
 +-------------+--------------------+
 |ELF_T_RELA   | Elf32_Rela         |
 +-------------+--------------------+
 |ELF_T_SHDR   | Elf32_Shdr         |
 +-------------+--------------------+
 |ELF_T_SWORD  | Elf32_Sword        |
 +-------------+--------------------+
 |ELF_T_SYM    | Elf32_Sym          |
 +-------------+--------------------+
 |ELF_T_WORD   | Elf32_Word         |
 +-------------+--------------------+
``Translating'' buffers of type ELF_T_BYTE does not change the byte order.

Return values

This function returns a pointer to the Elf_Data buffer or NULL.

Diagnostics

Error conditions are identified through the routine elf_error(S).

See also

elf(S), elf_fsize(S), elf_getdata(S), elf_getident(S)

Standards conformance

elf32_xlatetof(S) and elf32_xlatetom(S) are not part of any currently supported standard; they were developed by UNIX System Laboratories, Inc. and are maintained by The SCO Group.
© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003