EnderIce2 6dae34debd
userspace: Rewrite everything
Everything.

Signed-off-by: EnderIce2 <enderice2@protonmail.com>
2025-01-04 06:27:54 +02:00

101 lines
2.4 KiB
C

/*
This file is part of Fennix Userspace.
Fennix Userspace is free software: you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation, either version 3 of
the License, or (at your option) any later version.
Fennix Userspace 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with Fennix Userspace. If not, see <https://www.gnu.org/licenses/>.
*/
typedef void (*fct)(void);
#define asm __asm__ __volatile__
extern void (*__preinit_array_start[])(void) __attribute__((weak));
extern void (*__preinit_array_end[])(void) __attribute__((weak));
extern void (*__init_array_start[])(void) __attribute__((weak));
extern void (*__init_array_end[])(void) __attribute__((weak));
extern void (*__fini_array_start[])(void) __attribute__((weak));
extern void (*__fini_array_end[])(void) __attribute__((weak));
void __crt_init_array(void)
{
for (fct *func = __init_array_start; func != __init_array_end; func++)
(*func)();
}
void __crt_fini_array(void)
{
for (fct *func = __fini_array_start; func != __fini_array_end; func++)
(*func)();
}
__attribute__((naked, used, no_stack_protector, section(".text"))) void _start()
{
asm("movq $0, %rbp\n"
"pushq %rbp\n"
"pushq %rbp\n"
"movq %rsp, %rbp\n"
"pushq %rcx\n"
"pushq %rdx\n"
"pushq %rsi\n"
"pushq %rdi\n"
"call __libc_init\n"
"call __crt_init_array\n"
"popq %rdi\n"
"popq %rsi\n"
"popq %rdx\n"
"popq %rcx\n"
"call main\n"
"pushq %rax\n"
"call __crt_fini_array\n"
"popq %rax\n"
"movl %eax, %edi\n"
"call _exit\n");
}
/* These are declared in GNU ld */
enum
{
NT_FNX_ABI_TAG = 1,
NT_FNX_VERSION = 2,
NT_FNX_BUILD_ID = 3,
NT_FNX_ARCH = 4
};
typedef struct Elf_Nhdr
{
__UINT32_TYPE__ n_namesz;
__UINT32_TYPE__ n_descsz;
__UINT32_TYPE__ n_type;
char n_name[];
} __attribute__((packed)) Elf_Nhdr;
const struct
{
Elf_Nhdr header;
char name[4];
__UINT32_TYPE__ desc[4];
} __abi_tag __attribute__((aligned(4), section(".note.ABI-tag"))) = {
.header = {
.n_namesz = 4, /* "FNX" + '\0' */
.n_descsz = sizeof(__UINT32_TYPE__) * 4, /* Description Size */
.n_type = NT_FNX_ABI_TAG, /* Type */
},
.name = "FNX",
.desc = {0, 0, 0, 0},
};