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#include <init/tar.h>
#include <init/types.h>
#include <shared/flags.h>
#include <shared/syscalls.h>
#include <stdint.h>
#define argify(str) str, sizeof(str) - 1
#define log(str) _syscall_write(tty_fd, argify(str))
extern char _bss_start; // provided by the linker
extern char _bss_end;
extern char _initrd;
int tty_fd;
void fs_test(void);
void fs_server(handle_t back);
__attribute__((section(".text.startup")))
int main(void) {
// allocate bss
_syscall_memflag(&_bss_start, &_bss_end - &_bss_start, MEMFLAG_PRESENT);
tty_fd = _syscall_open("/tty", sizeof("/tty") - 1);
if (tty_fd < 0)
_syscall_exit(argify("couldn't open tty"));
fs_test();
tar_driver(&_initrd);
_syscall_exit(argify("my job here is done."));
}
void fs_test(void) {
handle_t front, back, file;
front = _syscall_fs_create(&back);
if (_syscall_fork()) {
// child: is the fs server
fs_server(back);
return;
}
// parent: accesses the fs
_syscall_mount(front, argify("/mnt"));
log("requesting file. ");
file = _syscall_open(argify("/mnt/tty"));
log("open returned. ");
_syscall_write(file, argify("hello"));
// try reading
char buf[8];
int len = 8;
for (int i = 0; i < 8; i++)
buf[i] = '.';
len = _syscall_read(file, buf, len);
_syscall_write(tty_fd, buf, len + 1); // read 1 byte past, should be a dot
}
void fs_server(handle_t back) {
static char buf[64];
int len, id;
for (;;) {
len = 64;
switch (_syscall_fs_wait(back, buf, &len, &id)) {
case VFSOP_OPEN:
_syscall_write(tty_fd, buf, len);
log(" was opened. ");
_syscall_fs_respond(NULL, 32); // doesn't check the path yet
break;
case VFSOP_READ:
// all reads output "world"
_syscall_fs_respond("world", 5);
break;
case VFSOP_WRITE:
// uppercase the buffer
for (int i = 0; i < len; i++) buf[i] &= ~id; // id == 32
// and passthrough to tty
_syscall_write(tty_fd, buf, len);
_syscall_fs_respond(NULL, len); // return the amt of bytes written
break;
default:
log("fuck");
break;
}
}
}
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