[kernel] Add the handle_close syscallnnAdd a generic handle_close syscall and use it in j6::channel when failing to open

definitions/syscalls.def

@@ -44,6 +44,11 @@ interface syscalls [syscall] {
         param mask uint32                        # The capability bitmask
     }
 
+    # Close the handle to an object
+    function handle_close {
+        param hnd ref object [handle] # The handle to close
+    }
+
     # Block waiting on a futex
     function futex_wait [static] {
         param address uint32*  # Address of the futex value

src/kernel/syscalls/handle.cpp

@@ -32,4 +32,13 @@ handle_clone(j6_handle_t orig, j6_handle_t *clone, uint32_t mask)
     return j6_status_ok;
 }
 
+
+j6_status_t
+handle_close(j6_handle_t hnd)
+{
+    process &p = process::current();
+    p.remove_handle(hnd);
+    return j6_status_ok;
+}
+
 } // namespace syscalls

src/libraries/j6/channel.cpp

@@ -79,7 +79,7 @@ channel::create(size_t tx_size, size_t rx_size)
     uintptr_t rx_addr = create_channel_vma(rx_vma, rx_size);
     if (!rx_addr) {
         j6_vma_unmap(tx_vma, 0);
-        // TODO: Close TX handle
+        j6_handle_close(tx_vma);
         return nullptr;
     }
 
@@ -109,7 +109,7 @@ channel::open(const channel_def &def)
     result = j6_vma_map(def.rx, 0, &rx_addr, 0);
     if (result != j6_status_ok) {
         j6_vma_unmap(def.tx, 0);
-        // TODO: Close TX handle
+        j6_handle_close(def.tx);
         syslog(j6::logs::ipc, j6::log_level::error, "Failed to map channel VMA. Error: %lx", result);
         return nullptr;
     }