add docs for syscalls. make syscall code kind-of cleaner

1 files changed, 33 insertions, 0 deletions

diff --git a/arch/x86_64/sys/syscall_serial.c b/arch/x86_64/sys/syscall_serial.c
new file mode 100644
index 0000000..786a78b
--- /dev/null
+++ b/arch/x86_64/sys/syscall_serial.c
@@ -0,0 +1,33 @@
+#include "jove.h"
+#include "lib/printf.h"
+#include "sys/syscall.h"
+#include "syscall.h"
+#include "arch/x86_64/hal/serial_com.h"
+
+static int
+s_syscall_serial_write(
+        jove_owned_obj_t *serial_com,
+        size_t payload_bytes,
+        void *payload_data)
+{
+    size_t bytes_needed = sizeof(struct syscall_generic_write);
+    CHECK_TOOSMALL(bytes_needed, payload_bytes, "Message is too small for this syscall!");
+
+    struct syscall_generic_write *payload = payload_data;
+    bytes_needed += payload->len * 2;
+    CHECK_TOOSMALL(bytes_needed, payload_bytes, "Message is too small for write buffer!");
+    
+    return serial_com_write(serial_com, payload->data, payload->len);
+}
+
+int
+_syscall_handle_serial(syscall_context_t *ctx)
+{
+    switch(ctx->header->callid) {
+        case SYSCALL_SERIAL_COM_WRITE:
+            return s_syscall_serial_write(ctx->target.obj, ctx->bytes_left, ctx->payload);
+        default:
+            kprintf("syscall_serial: serial com object does not support syscall %i\n", ctx->header->callid);
+            return -EBADCALL;
+    }
+}