rename file descriptors to handles

1 files changed, 55 insertions, 0 deletions

diff --git a/src/kernel/handle.c b/src/kernel/handle.c
new file mode 100644
index 0000000..6e25b74
--- /dev/null
+++ b/src/kernel/handle.c
@@ -0,0 +1,55 @@
+#include <kernel/handle.h>
+#include <kernel/mem.h>
+#include <kernel/panic.h>
+#include <kernel/proc.h>
+
+static int handleop_special_tty(struct handleop_args *args);
+
+int handleop_dispatch(struct handleop_args args) {
+	switch(args.handle->type) {
+		case HANDLE_EMPTY: {
+			if (args.type == HANDLEOP_MOUNT) // mounting an empty handle is allowed
+				return 0;
+			return -1;
+		}
+		case HANDLE_SPECIAL_TTY:
+			return handleop_special_tty(&args);
+		default:
+			panic();
+	}
+}
+
+static int handleop_special_tty(struct handleop_args *args) {
+	switch(args->type) {
+		case HANDLEOP_MOUNT:
+			return 0; // no special action needed
+
+		case HANDLEOP_OPEN:
+			/* don't allow anything after the mount point
+			 * this is a file, not a directory
+			 * for example: open("/tty") is allowed. open("/tty/smth") isn't */
+			if (args->open.len == 0) {
+				args->open.target->type = HANDLE_SPECIAL_TTY;
+				return 0;
+			}
+			return -1;
+
+		case HANDLEOP_READ:
+			return -1; // input not implemented yet
+
+		case HANDLEOP_WRITE: {
+			 struct virt_iter iter;
+			 virt_iter_new(&iter, args->rw.ptr, args->rw.len,
+					 process_current->pages, true, false);
+			 while (virt_iter_next(&iter))
+				 tty_write(iter.frag, iter.frag_len);
+			 return iter.prior;
+		}
+
+		case HANDLEOP_CLOSE:
+			args->handle->type = HANDLE_EMPTY;
+			return 0;
+
+		default: panic();
+	}
+}