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#include <linux/auxvec.h> // for AT_NULL
#include <linux/elf.h> // for Elf64_Ehdr
#include "asm/auxvec.h" // for AT_SYSINFO_EHDR
#include <stdint.h> // for uintptr_t
#include <stdlib.h> // for exit
#define weak_reference(old, new) \
extern __typeof(old) new __attribute__((__weak__, __alias__(#old)))
extern int main(int, char *[]);
char **environ;
struct __attribute__((packed)) auxv_t {
uintptr_t a_type;
uintptr_t a_val;
} *__auxv;
static void __vdso_setup(Elf64_Ehdr *vdso_addr __attribute__((unused)))
{
}
weak_reference(__vdso_setup, vdso_setup);
__attribute__((used)) void __libc_start(uintptr_t *sp)
{
char **argv;
int argc;
argc = (int)(*sp);
argv = (char **)(++sp);
sp += argc;
environ = (char **)(++sp);
while (*sp)
sp++;
__auxv = (struct auxv_t *)(++sp);
while (__auxv->a_type != AT_NULL) {
if (__auxv->a_type == AT_SYSINFO_EHDR) {
vdso_setup((Elf64_Ehdr *)__auxv->a_val);
}
__auxv++;
}
exit(main(argc, argv));
}
__attribute__((noreturn, naked)) void _start(void)
{
__asm__ __volatile__("mov %rsp, %rdi\n"
"call __libc_start\n");
}
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