feat: IPC: use C-lock pattern to retain IPC transfers.

Signed-off-by: Amlal El Mahrouss <amlal@nekernel.org>

2 files changed, 21 insertions, 1 deletions

diff --git a/dev/kernel/NetworkKit/IPC.h b/dev/kernel/NetworkKit/IPC.h
index 0dd8a1f1..d14356c0 100644
--- a/dev/kernel/NetworkKit/IPC.h
+++ b/dev/kernel/NetworkKit/IPC.h
@@ -57,6 +57,12 @@ enum {
 
 constexpr inline auto kIPCMsgSize = 6094U;
 
+enum {
+  kIPCLockInvalid,
+  kIPCLockFree = 1,
+  kIPCLockUsed = 2,
+};
+
 /// @brief IPC connection header, message cannot be greater than 6K.
 typedef struct IPC_MSG final {
   UInt32   IpcHeaderMagic;  // cRemoteHeaderMagic
@@ -68,7 +74,7 @@ typedef struct IPC_MSG final {
   UInt32   IpcMsg;
   UInt32   IpcMsgSz;
   UInt8    IpcData[kIPCMsgSize];
-
+  UInt32   IpcLock;
   /// @brief Passes the message to target, could be anything, HTTP packet, JSON or whatever.
   static Bool Pass(IPC_MSG* self, IPC_MSG* target) noexcept;
 } PACKED IPC_MSG;
diff --git a/dev/kernel/src/Network/IPCMsg.cc b/dev/kernel/src/Network/IPCMsg.cc
index 6f54e449..9abefcef 100644
--- a/dev/kernel/src/Network/IPCMsg.cc
+++ b/dev/kernel/src/Network/IPCMsg.cc
@@ -87,6 +87,8 @@ Bool ipc_construct_packet(_Output IPC_MSG** pckt_in) {
     (*pckt_in)->IpcFrom.UserProcessID   = 0;
     (*pckt_in)->IpcFrom.UserProcessTeam = 0;
 
+    (*pckt_in)->IpcLock = kIPCLockFree;
+
     return Yes;
   }
 
@@ -103,8 +105,20 @@ Bool IPC_MSG::Pass(IPC_MSG* src, IPC_MSG* target) noexcept {
     if (src->IpcMsgSz > target->IpcMsgSz) return No;
     if (target->IpcMsgSz > src->IpcMsgSz) return No;
 
+    UInt32 timeout = 0U;
+
+    while ((target->IpcLock % kIPCLockUsed) != 0) {
+      if (timeout > 100000U) {
+        return No;
+      }
+    }
+
+    ++target->IpcLock;
+
     rt_copy_memory_safe(src->IpcData, target->IpcData, src->IpcMsgSz, kIPCMsgSize);
 
+    --target->IpcLock;
+
     return Yes;
   }