1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
#include <stdio.h>
#include <err.h>
#include <endian.h>
#include <stdint.h>
#include <sys/types.h>
#define ANSI_FG_RED "\033[0;31m"
/* This program pipes it's argument file to stdout prepending it */
/* with it's size (4 bytes, little endian). It is intended to be used */
/* with our bootloader (i.e. by piping kernel image to UART). */
int main(int argc, char **argv) {
char *image_file_name = argc > 1 ? argv[1] : "kernel7.img";
FILE *image_file_handle = fopen(image_file_name, "r");
if (!image_file_handle)
err(-1, "couldn't open" ANSI_FG_RED "%s", image_file_name);
if (fseek(image_file_handle, 0, SEEK_END))
err(-1, "error navigating through file");
ssize_t image_size = ftell(image_file_handle);
if (image_size < 0)
err(-1, "couldn't get image file size");
if (image_size >> 32)
err(-1, "file to big (should be smaller than 4G)");
if (fseek(image_file_handle, 0, SEEK_SET))
err(-1, "error navigating through file");
uint32_t image_size_le = htole32(image_size);
if (fwrite(&image_size_le, 4, 1, stdout) != 1)
err(-1, "couldn't write to stdout");
ssize_t bytes_left = image_size;
char buf[1024];
while (bytes_left)
{
size_t bytes_read;
if ((bytes_read = fread(buf, 1, sizeof(buf), image_file_handle))
< 1)
err(-1, "error reading the file");
if (fwrite(buf, bytes_read, 1, stdout) != 1)
err(-1, "error writing to stdout");
bytes_left -= bytes_read;
}
}
|
