cosmopolitan/libc/elf/struct/rel.h
Justine Tunney fa20edc44d
Reduce header complexity
- Remove most __ASSEMBLER__ __LINKER__ ifdefs
- Rename libc/intrin/bits.h to libc/serialize.h
- Block pthread cancelation in fchmodat() polyfill
- Remove `clang-format off` statements in third_party
2023-11-28 14:39:42 -08:00

52 lines
1.3 KiB
C

#ifndef COSMOPOLITAN_LIBC_ELF_STRUCT_REL_H_
#define COSMOPOLITAN_LIBC_ELF_STRUCT_REL_H_
#include "libc/elf/scalar.h"
/*
* ELF relocation.
*
* Relocations let us easily apply fixups to compiled object code. This
* data structure represents the contents of an `sh_type` w/ `SHT_REL`.
*
* @see Elf64_Rela
*/
typedef struct Elf64_Rel {
/*
* Location to be modified.
*
* If `e_type` is `ET_REL` then this is a section data byte offset.
*
* If `e_type` isn't `ET_REL` then this is a virtual address.
*/
Elf64_Addr r_offset;
/*
* Relocation type and symbol.
*
* This value may be created using:
*
* r_info = ELF64_R_INFO(sym, type);
*
* This value may be read using:
*
* Elf64_Word sym = ELF64_R_SYM(r_info);
* Elf64_Word type = ELF64_R_TYPE(r_info);
*
* Where `sym` is a symbol index, and `type` might be:
*
* - `R_X86_64_64`
* - `R_X86_64_PC32`
* - `R_X86_64_GOTPCRELX`
* - `R_AARCH64_ABS64`
*
* Each relocation type specifies a mathematical formula that's used
* to compute the appropriate value for the fixed-up object code. If
* it needs an addend, then this struct doesn't have one, but it can
* still be embedded by the compiler in the location to be modified.
*/
Elf64_Xword r_info;
} Elf64_Rel;
#endif /* COSMOPOLITAN_LIBC_ELF_STRUCT_REL_H_ */