init: implement a halfassed passthrough fs

2 files changed, 36 insertions, 0 deletions

diff --git a/src/init/fs/misc.c b/src/init/fs/misc.c
new file mode 100644
index 0000000..134c311
--- /dev/null
+++ b/src/init/fs/misc.c
@@ -0,0 +1,33 @@
+#include <init/stdlib.h>
+#include <shared/flags.h>
+#include <shared/syscalls.h>
+
+void fs_passthru() {
+	struct fs_wait_response res;
+	int buf_size = 64;
+	char buf[      64];
+	int ret;
+
+	for (;;) {
+		switch (_syscall_fs_wait(buf, buf_size, &res)) {
+			case VFSOP_OPEN:
+				ret = _syscall_open(buf, res.len);
+				_syscall_fs_respond(NULL, ret);
+				break;
+
+			case VFSOP_READ:
+				if (res.capacity > buf_size)
+					res.capacity = buf_size; /* don't overflow the buffer */
+				ret = _syscall_read(res.id, buf, res.capacity, res.offset);
+				_syscall_fs_respond(buf, ret);
+				break;
+
+			// temporarily doesn't support writing
+			// also TODO closing
+
+			default:
+				_syscall_fs_respond(NULL, -1);
+				break;
+		}
+	}
+}
diff --git a/src/init/fs/misc.h b/src/init/fs/misc.h
new file mode 100644
index 0000000..6afca79
--- /dev/null
+++ b/src/init/fs/misc.h
@@ -0,0 +1,3 @@
+#pragma once
+
+void fs_passthru();