From fa7d66d196e0aa4577bb246ea7d5af381824c0cc Mon Sep 17 00:00:00 2001
From: Shuntian Liu <shuntian.liu@outlook.com>
Date: Fri, 2 Aug 2024 00:33:34 +0100
Subject: [PATCH] cpg: initial binding to libcpg

---
 lib/cpg.ml | 104 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 lib/cpg.ml

diff --git a/lib/cpg.ml b/lib/cpg.ml
new file mode 100644
index 0000000..6aaba97
--- /dev/null
+++ b/lib/cpg.ml
@@ -0,0 +1,104 @@
+open Ctypes
+open Foreign
+open Corotypes
+open CsError
+
+let ( >>= ) = Result.bind
+
+let cpg_handle_t = uint64_t
+
+type cpg_name
+
+let cpg_name : cpg_name structure typ = structure "cpg_name"
+
+let cpg_name_length = field cpg_name "length" uint32_t
+
+let cpg_name_value = field cpg_name "value" (ptr char)
+
+let () = seal cpg_name
+
+type cpg_address
+
+let cpg_address : cpg_address structure typ = structure "cpg_address"
+
+let nodeid = field cpg_address "nodeid" uint32_t
+
+let pid = field cpg_address "pid" uint32_t
+
+let reason = field cpg_address "reason" uint32_t
+
+let () = seal cpg_address
+
+let cpg_deliver_fn_t =
+  cpg_handle_t @-> ptr cpg_name @-> uint32_t @-> uint32_t @-> returning void
+
+let cpg_confchg_fn_t =
+  cpg_handle_t
+  @-> ptr cpg_name
+  @-> ptr cpg_address
+  @-> size_t
+  @-> ptr cpg_address
+  @-> size_t
+  @-> cpg_address
+  @-> size_t
+  @-> returning void
+
+(* struct cpg_callbacks_t *)
+
+type cpg_callbacks_t
+
+let cpg_callbacks_t : cpg_callbacks_t structure typ =
+  structure "cpg_callbacks_t"
+
+let cpg_deliver_fn =
+  field cpg_callbacks_t "cpg_deliver_fn" (funptr cpg_deliver_fn_t)
+
+let cpg_confchg_fn =
+  field cpg_callbacks_t "cpg_confchg_fn" (funptr cpg_confchg_fn_t)
+
+let () = seal cpg_callbacks_t
+
+(* cpg bindings *)
+
+let cpg_initialize =
+  foreign "cpg_initialize"
+    (ptr cpg_handle_t @-> ptr cpg_callbacks_t @-> returning cs_error_t)
+
+let cpg_finalize = foreign "cpg_finalize" (cpg_handle_t @-> returning cs_error_t)
+
+let cpg_fd_get =
+  foreign "cpg_fd_get" (cpg_handle_t @-> ptr int @-> returning cs_error_t)
+
+let cpg_join =
+  foreign "cpg_join" (cpg_handle_t @-> ptr cpg_name @-> returning cs_error_t)
+
+let cpg_leave =
+  foreign "cpg_leave" (cpg_handle_t @-> ptr cpg_name @-> returning cs_error_t)
+
+let cpg_membership_get =
+  foreign "cpg_member_ship_get"
+    (cpg_handle_t
+    @-> ptr cpg_name
+    @-> ptr cpg_address
+    @-> ptr int
+    @-> returning cs_error_t
+    )
+
+let cpg_local_get =
+  foreign "cpg_local_get" (cpg_handle_t @-> ptr uint @-> returning cs_error_t)
+
+(* ocaml APIs *)
+let with_handle f =
+  let handle = allocate cpg_handle_t Unsigned.UInt64.zero in
+  cpg_initialize handle (from_voidp cpg_callbacks_t null)
+  |> CsError.to_result
+  >>= fun () ->
+  let r = f !@handle in
+  cpg_finalize !@handle |> CsError.to_result >>= fun () -> r
+
+let fd_get handle = 
+  let fd = allocate int 0 in
+  cpg_fd_get handle fd |> to_result >>= fun () ->
+  Ok !@fd
+
+