[interface] Provide the ability to shut down multiple interfaces

Shutting down (and optionally restarting) multiple interfaces is
fraught with problems if there are loops in the interface connectivity
(e.g. the HTTP content-decoded and transfer-decoded interfaces, which
will generally loop back to each other).  Various workarounds
currently exist across the codebase, generally involving preceding
calls to intf_nullify() to avoid problems due to known loops.

Provide intfs_shutdown() and intfs_restart() to allow all of an
object's interfaces to be shut down (or restarted) in a single call,
without having to worry about potential external loops.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/core/interface.c b/src/core/interface.c
index f7802be071c0d94c2fb064b3cad16348956e6a04..402aa45415059b009e4fbc5e8bfd325cece691de 100644 (file)
--- a/src/core/interface.c
+++ b/src/core/interface.c
@@ -290,6 +290,41 @@ void intf_shutdown ( struct interface *intf, int rc ) {
        intf_unplug ( &tmp );
 }
 
+/**
+ * Shut down multiple object interfaces
+ *
+ * @v intfs            Object interfaces
+ * @v rc               Reason for close
+ */
+void intfs_vshutdown ( va_list intfs, int rc ) {
+       struct interface *intf;
+       va_list tmp;
+
+       /* Nullify all interfaces to avoid potential loops */
+       va_copy ( tmp, intfs );
+       while ( ( intf = va_arg ( tmp, struct interface * ) ) )
+               intf_nullify ( intf );
+       va_end ( tmp );
+
+       /* Shut down all interfaces */
+       while ( ( intf = va_arg ( intfs, struct interface * ) ) )
+               intf_shutdown ( intf, rc );
+}
+
+/**
+ * Shut down multiple object interfaces
+ *
+ * @v rc               Reason for close
+ * @v ...              Object interfaces
+ */
+void intfs_shutdown ( int rc, ... ) {
+       va_list intfs;
+
+       va_start ( intfs, rc );
+       intfs_vshutdown ( intfs, rc );
+       va_end ( intfs );
+}
+
 /**
  * Shut down and restart an object interface
  *
@@ -316,6 +351,40 @@ void intf_restart ( struct interface *intf, int rc ) {
        intf_reinit ( intf );
 }
 
+/**
+ * Shut down and restart multiple object interfaces
+ *
+ * @v intfs            Object interfaces
+ * @v rc               Reason for close
+ */
+void intfs_vrestart ( va_list intfs, int rc ) {
+       struct interface *intf;
+       va_list tmp;
+
+       /* Shut down all interfaces */
+       va_copy ( tmp, intfs );
+       intfs_vshutdown ( tmp, rc );
+       va_end ( tmp );
+
+       /* Reinitialise all interfaces */
+       while ( ( intf = va_arg ( intfs, struct interface * ) ) )
+               intf_reinit ( intf );
+}
+
+/**
+ * Shut down and restart multiple object interfaces
+ *
+ * @v rc               Reason for close
+ * @v ...              Object interfaces
+ */
+void intfs_restart ( int rc, ... ) {
+       va_list intfs;
+
+       va_start ( intfs, rc );
+       intfs_vrestart ( intfs, rc );
+       va_end ( intfs );
+}
+
 /**
  * Poke an object interface
  *

diff --git a/src/include/ipxe/interface.h b/src/include/ipxe/interface.h
index ebb1b691114a366f56805db21266236bc1db496c..b65002c805f8ec5d107b7423d97af9e801978974 100644 (file)
--- a/src/include/ipxe/interface.h
+++ b/src/include/ipxe/interface.h
@@ -10,6 +10,7 @@
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stddef.h>
+#include <stdarg.h>
 #include <ipxe/refcnt.h>
 
 /** An object interface operation */
@@ -148,7 +149,11 @@ extern void intf_close ( struct interface *intf, int rc );
        typeof ( void ( object_type, int rc ) )
 
 extern void intf_shutdown ( struct interface *intf, int rc );
+extern void intfs_vshutdown ( va_list intfs, int rc );
+extern void intfs_shutdown ( int rc, ... ) __attribute__ (( sentinel ));
 extern void intf_restart ( struct interface *intf, int rc );
+extern void intfs_vrestart ( va_list intfs, int rc );
+extern void intfs_restart ( int rc, ... ) __attribute__ (( sentinel ));
 
 extern void intf_poke ( struct interface *intf,
                        void ( type ) ( struct interface *intf ) );