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#include <posix/unistd.h>
#include <posix/fcntl.h>
#include <kjarna/interface.h>
#include <libc/string.h>
#include <libc/stdio.h>
#include <libc/stdlib.h>
#include <lib/elf.h>
#include <posix/unistd.h>
#include <posix/sys/mman.h>
#include "kjarna_efi.h"
#include "config.h"
#include <efi/error.h>
static int create_image_buffer(int fd, struct image_buffer *buffer)
{
if ((buffer->length = elf64_size_fd(fd)) == 0)
{
return -1;
}
printf("creating image buffer, %d bytes\n", buffer->length);
if((buffer->base = mmap(nullptr, buffer->length, 0, 0, -1, 0)) == MAP_FAILED)
{
buffer->length = 0;
buffer->base = nullptr;
return -1;
}
printf("image buffer base %p\n", buffer->base);
return 0;
}
static struct image_buffer load_image(void)
{
const char *image_entry_path = SERVICE_FILE_PATH;
int image_fd;
struct image_buffer buffer = { nullptr, 0 };
if ((image_fd = open(image_entry_path, O_RDONLY, 0)) == -1)
{
return buffer;
}
if (!elf64_validate_fd(image_fd, ET_DYN, EM_X86_64))
{
return buffer;
}
if (create_image_buffer(image_fd, &buffer) < 0)
{
return buffer;
}
if (buffer.base != nullptr && elf64_load_segments(image_fd, buffer.length, buffer.base) < 0)
{
printf("error detected: buffer {base: %p, length: %zu}\n", buffer.base, buffer.length);
munmap(buffer.base, buffer.length);
buffer.base = nullptr;
}
close(image_fd);
return buffer;
}
kjarna_image_entry_func *image_entry_addr(struct image_buffer *buffer)
{
if (buffer->base == nullptr)
{
return nullptr;
}
Elf64_Ehdr *ehdr = (Elf64_Ehdr *)buffer->base;
return (kjarna_image_entry_func *)(buffer->base + ehdr->e_entry);
}
struct kjarna_interface get_boot_interface(void)
{
struct kjarna_interface result =
{
efi_open,
efi_close,
efi_lseek,
efi_read,
efi_write,
efi_mmap,
efi_munmap
};
return result;
}
struct kjarna_boot_image get_boot_image(void)
{
struct kjarna_boot_image image =
{
{ nullptr, 0 },
nullptr
};
image.buffer = load_image();
if (image.buffer.base != nullptr)
{
image.entry = image_entry_addr(&image.buffer);
}
return image;
}
int image_start(void)
{
struct kjarna_interface interface = get_boot_interface();
struct kjarna_entry_params params =
{
&interface,
0,
nullptr,
nullptr
};
struct kjarna_boot_image image = get_boot_image();
if (image.buffer.base != nullptr)
{
image.entry = image_entry_addr(&image.buffer);
}
if (image.entry != nullptr)
{
image.entry(¶ms);
}
if (munmap(image.buffer.base, image.buffer.length) == -1)
{
write(STDOUT_FILENO, "failed unmap\r\n", -1);
if (efi_errno == EFI_NOT_FOUND)
{
write(STDOUT_FILENO, "not found\r\n", -1);
}
else
{
write(STDOUT_FILENO, "bad alignment?\r\n", -1);
}
}
return -1;
}
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