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#include <kernel/mem/virt.h>
#include <kernel/panic.h>
#include <kernel/proc.h>
#include <kernel/util.h>
#include <kernel/vfs/root.h>
enum {
HANDLE_ROOT,
HANDLE_TTY,
};
int vfs_root_handler(struct vfs_request *req) {
switch (req->type) {
case VFSOP_OPEN:
assert(req->input.kern);
if (req->input.len == 1 && *req->input.buf_kern == '/')
return HANDLE_ROOT;
if (req->input.len == 4
&& !memcmp(req->input.buf_kern, "/tty", 4)) {
return HANDLE_TTY;
}
return -1;
case VFSOP_READ:
switch (req->id) {
case HANDLE_ROOT: {
const char *src = "tty"; // TODO document directory read format
int srclen = 4; // TODO port strlen to the kernel
int len = req->output.len;
if (len < 0) return 0; // is this needed?
if (len > srclen) len = srclen;
virt_cpy_to(req->caller->pages, req->output.buf, src, len);
return len;
}
case HANDLE_TTY: {
struct virt_iter iter;
virt_iter_new(&iter, req->output.buf, req->output.len,
req->caller->pages, true, false);
while (virt_iter_next(&iter))
tty_read(iter.frag, iter.frag_len);
return iter.prior;
}
default: panic_invalid_state();
}
case VFSOP_WRITE:
switch (req->id) {
case HANDLE_ROOT: return -1;
case HANDLE_TTY: {
struct virt_iter iter;
virt_iter_new(&iter, req->input.buf, req->input.len,
req->caller->pages, true, false);
while (virt_iter_next(&iter))
tty_write(iter.frag, iter.frag_len);
return iter.prior;
}
default: panic_invalid_state();
}
default: panic_invalid_state();
}
}
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