elf_loader 0.12.0

A pure-rust library for loading all ELF format files from both memory and files.
Documentation 
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use elf::abi::*;

pub const EM_ARCH: u16 = EM_ARM;
pub const TLS_DTV_OFFSET: usize = 0;

pub const REL_RELATIVE: u32 = R_ARM_RELATIVE;
pub const REL_GOT: u32 = R_ARM_GLOB_DAT;
pub const REL_DTPMOD: u32 = R_ARM_TLS_DTPMOD32;
pub const REL_SYMBOLIC: u32 = R_ARM_ABS32;
pub const REL_JUMP_SLOT: u32 = R_ARM_JUMP_SLOT;
pub const REL_DTPOFF: u32 = R_ARM_TLS_DTPOFF32;
pub const REL_IRELATIVE: u32 = R_ARM_IRELATIVE;
pub const REL_COPY: u32 = R_ARM_COPY;
pub const REL_TPOFF: u32 = R_ARM_TLS_TPOFF32;

#[cfg(feature = "lazy")]
core::arch::global_asm!(
    "
    .text
    .globl dl_runtime_resolve
	.type dl_runtime_resolve, %function
	.align 16
dl_runtime_resolve:
    push {{r0, r1, r2, r3, r4}}
    ldr r0, [lr, #-4]
    add r1, lr, #4 
	sub r1, ip, r1
    lsr r1, r1, 2
    bl dl_fixup
    mov	ip, r0
    pop	{{r0, r1, r2, r3, r4, lr}}
    bx ip
"
);

#[cfg(feature = "lazy")]
pub(crate) fn prepare_lazy_bind(got: *mut usize, dylib: usize) {
    unsafe extern "C" {
        fn dl_runtime_resolve();
    }
    // 这是安全的，延迟绑定时库是存在的
    unsafe {
        got.add(1).write(dylib);
        got.add(2).write(dl_runtime_resolve as usize);
    }
}