r15188: Restore svn rev. 15183, 15184 and 15185, which I inadvertantly clobbered

in r15186. I don't think I should be allowed to use quilt and svn at the
same time any more :(
(This used to be commit e0ca5ead27743c84f5d9310a05d6d718862ead1d)

9 files changed, 75 insertions, 22 deletions

diff --git a/source4/ntvfs/cifs/vfs_cifs.c b/source4/ntvfs/cifs/vfs_cifs.c
index 25fe4cb2a4..586e0ebb98 100644
--- a/source4/ntvfs/cifs/vfs_cifs.c
+++ b/source4/ntvfs/cifs/vfs_cifs.c
@@ -939,6 +939,7 @@ NTSTATUS ntvfs_cifs_init(void)
 {
 	NTSTATUS ret;
 	struct ntvfs_ops ops;
+	NTVFS_CURRENT_CRITICAL_SIZES(vers);
 
 	ZERO_STRUCT(ops);
 
@@ -985,7 +986,7 @@ NTSTATUS ntvfs_cifs_init(void)
 
 	/* register ourselves with the NTVFS subsystem. We register
 	   under the name 'cifs'. */
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 
 	if (!NT_STATUS_IS_OK(ret)) {
 		DEBUG(0,("Failed to register CIFS backend!\n"));
diff --git a/source4/ntvfs/ipc/vfs_ipc.c b/source4/ntvfs/ipc/vfs_ipc.c
index b6b931eccd..6ef380c4eb 100644
--- a/source4/ntvfs/ipc/vfs_ipc.c
+++ b/source4/ntvfs/ipc/vfs_ipc.c
@@ -777,6 +777,7 @@ NTSTATUS ntvfs_ipc_init(void)
 {
 	NTSTATUS ret;
 	struct ntvfs_ops ops;
+	NTVFS_CURRENT_CRITICAL_SIZES(vers);
 
 	ZERO_STRUCT(ops);
 	
@@ -817,7 +818,7 @@ NTSTATUS ntvfs_ipc_init(void)
 	ops.cancel = ipc_cancel;
 
 	/* register ourselves with the NTVFS subsystem. */
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 
 	if (!NT_STATUS_IS_OK(ret)) {
 		DEBUG(0,("Failed to register IPC backend!\n"));
diff --git a/source4/ntvfs/nbench/vfs_nbench.c b/source4/ntvfs/nbench/vfs_nbench.c
index b93e5f3c44..a8ec141760 100644
--- a/source4/ntvfs/nbench/vfs_nbench.c
+++ b/source4/ntvfs/nbench/vfs_nbench.c
@@ -884,6 +884,7 @@ NTSTATUS ntvfs_nbench_init(void)
 {
 	NTSTATUS ret;
 	struct ntvfs_ops ops;
+	NTVFS_CURRENT_CRITICAL_SIZES(vers);
 
 	ZERO_STRUCT(ops);
 
@@ -928,7 +929,7 @@ NTSTATUS ntvfs_nbench_init(void)
 	ops.trans2 = NULL;
 
 	/* register ourselves with the NTVFS subsystem. */
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 
 	if (!NT_STATUS_IS_OK(ret)) {
 		DEBUG(0,("Failed to register nbench backend!\n"));
diff --git a/source4/ntvfs/ntvfs.h b/source4/ntvfs/ntvfs.h
index ec1f741fa8..3d12c5efc9 100644
--- a/source4/ntvfs/ntvfs.h
+++ b/source4/ntvfs/ntvfs.h
@@ -266,6 +266,17 @@ struct ntvfs_critical_sizes {
 	int sizeof_ntvfs_request;
 };
 
+#define NTVFS_CURRENT_CRITICAL_SIZES(c) \
+    struct ntvfs_critical_sizes c = { \
+	.interface_version		= NTVFS_INTERFACE_VERSION, \
+	.sizeof_ntvfs_critical_sizes	= sizeof(struct ntvfs_critical_sizes), \
+	.sizeof_ntvfs_context		= sizeof(struct ntvfs_context), \
+	.sizeof_ntvfs_module_context	= sizeof(struct ntvfs_module_context), \
+	.sizeof_ntvfs_ops		= sizeof(struct ntvfs_ops), \
+	.sizeof_ntvfs_async_state	= sizeof(struct ntvfs_async_state), \
+	.sizeof_ntvfs_request		= sizeof(struct ntvfs_request), \
+    }
+
 struct messaging_context;
 #include "librpc/gen_ndr/security.h"
 #include "librpc/gen_ndr/notify.h"
diff --git a/source4/ntvfs/ntvfs_base.c b/source4/ntvfs/ntvfs_base.c
index b1efb44ec7..316a9e9c68 100644
--- a/source4/ntvfs/ntvfs_base.c
+++ b/source4/ntvfs/ntvfs_base.c
@@ -44,11 +44,18 @@ static int num_backends;
 
   The 'type' is used to specify whether this is for a disk, printer or IPC$ share
 */
-_PUBLIC_ NTSTATUS ntvfs_register(const void *_ops)
+_PUBLIC_ NTSTATUS ntvfs_register(const struct ntvfs_ops *ops,
+				 const struct ntvfs_critical_sizes *const sizes)
 {
-	const struct ntvfs_ops *ops = _ops;
 	struct ntvfs_ops *new_ops;
-	
+
+	if (ntvfs_interface_differs(sizes)) {
+		DEBUG(0, ("NTVFS backend '%s' for type %d "
+			  "failed version check\n",
+			  ops->name, (int)ops->type));
+		return NT_STATUS_BAD_FUNCTION_TABLE;
+	}
+
 	if (ntvfs_backend_byname(ops->name, ops->type) != NULL) {
 		/* its already registered! */
 		DEBUG(0,("NTVFS backend '%s' for type %d already registered\n", 
@@ -98,21 +105,49 @@ _PUBLIC_ const struct ntvfs_ops *ntvfs_backend_byname(const char *name, enum ntv
   This can be used by backends to either detect compilation errors, or provide
   multiple implementations for different smbd compilation options in one module
 */
-static const struct ntvfs_critical_sizes critical_sizes = {
-	.interface_version		= NTVFS_INTERFACE_VERSION,
-	.sizeof_ntvfs_critical_sizes	= sizeof(struct ntvfs_critical_sizes),
-	.sizeof_ntvfs_context		= sizeof(struct ntvfs_context),
-	.sizeof_ntvfs_module_context	= sizeof(struct ntvfs_module_context),
-	.sizeof_ntvfs_ops		= sizeof(struct ntvfs_ops),
-	.sizeof_ntvfs_async_state	= sizeof(struct ntvfs_async_state),
-	.sizeof_ntvfs_request		= sizeof(struct ntvfs_request),
-};
+
+static const NTVFS_CURRENT_CRITICAL_SIZES(critical_sizes);
 
 _PUBLIC_ const struct ntvfs_critical_sizes *ntvfs_interface_version(void)
 {
 	return &critical_sizes;
 }
 
+_PUBLIC_ BOOL ntvfs_interface_differs(const struct ntvfs_critical_sizes *const iface)
+{
+	/* The comparison would be easier with memcmp, but compiler-interset
+	 * alignment padding is not guaranteed to be zeroed.
+	 */
+
+#define FIELD_DIFFERS(field) (iface->field != critical_sizes.field)
+
+	if (FIELD_DIFFERS(interface_version))
+		return True;
+
+	if (FIELD_DIFFERS(sizeof_ntvfs_critical_sizes))
+		return True;
+
+	if (FIELD_DIFFERS(sizeof_ntvfs_context))
+		return True;
+
+	if (FIELD_DIFFERS(sizeof_ntvfs_module_context))
+		return True;
+
+	if (FIELD_DIFFERS(sizeof_ntvfs_ops))
+		return True;
+
+	if (FIELD_DIFFERS(sizeof_ntvfs_async_state))
+		return True;
+
+	if (FIELD_DIFFERS(sizeof_ntvfs_request))
+		return True;
+
+	/* Versions match. */
+	return False;
+
+#undef FIELD_DIFFERS
+}
+
 
 /*
   initialise a connection structure to point at a NTVFS backend
diff --git a/source4/ntvfs/posix/vfs_posix.c b/source4/ntvfs/posix/vfs_posix.c
index eddc49c919..2d40ceb85d 100644
--- a/source4/ntvfs/posix/vfs_posix.c
+++ b/source4/ntvfs/posix/vfs_posix.c
@@ -286,6 +286,7 @@ NTSTATUS ntvfs_posix_init(void)
 {
 	NTSTATUS ret;
 	struct ntvfs_ops ops;
+	NTVFS_CURRENT_CRITICAL_SIZES(vers);
 
 	ZERO_STRUCT(ops);
 
@@ -328,14 +329,14 @@ NTSTATUS ntvfs_posix_init(void)
 	   under the name 'default' as we wish to be the default
 	   backend, and also register as 'posix' */
 	ops.name = "default";
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 
 	if (!NT_STATUS_IS_OK(ret)) {
 		DEBUG(0,("Failed to register POSIX backend as '%s'!\n", ops.name));
 	}
 
 	ops.name = "posix";
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 
 	if (!NT_STATUS_IS_OK(ret)) {
 		DEBUG(0,("Failed to register POSIX backend as '%s'!\n", ops.name));
diff --git a/source4/ntvfs/print/vfs_print.c b/source4/ntvfs/print/vfs_print.c
index 1aa38a59c2..31cfcc9303 100644
--- a/source4/ntvfs/print/vfs_print.c
+++ b/source4/ntvfs/print/vfs_print.c
@@ -100,6 +100,7 @@ NTSTATUS ntvfs_print_init(void)
 {
 	NTSTATUS ret;
 	struct ntvfs_ops ops;
+	NTVFS_CURRENT_CRITICAL_SIZES(vers);
 
 	ZERO_STRUCT(ops);
 
@@ -115,7 +116,7 @@ NTSTATUS ntvfs_print_init(void)
 
 	/* register ourselves with the NTVFS subsystem. We register under the name 'default'
 	   as we wish to be the default backend */
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 
 	if (!NT_STATUS_IS_OK(ret)) {
 		DEBUG(0,("Failed to register PRINT backend!\n"));
diff --git a/source4/ntvfs/simple/vfs_simple.c b/source4/ntvfs/simple/vfs_simple.c
index 2347f31bde..35c18e3f1c 100644
--- a/source4/ntvfs/simple/vfs_simple.c
+++ b/source4/ntvfs/simple/vfs_simple.c
@@ -969,6 +969,7 @@ NTSTATUS ntvfs_simple_init(void)
 {
 	NTSTATUS ret;
 	struct ntvfs_ops ops;
+	NTVFS_CURRENT_CRITICAL_SIZES(vers);
 
 	ZERO_STRUCT(ops);
 
@@ -1010,7 +1011,7 @@ NTSTATUS ntvfs_simple_init(void)
 
 	ops.type = NTVFS_DISK;
 	ops.name = "simple";
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 
 	if (!NT_STATUS_IS_OK(ret)) {
 		DEBUG(0,("Failed to register simple backend with name: %s!\n",
diff --git a/source4/ntvfs/unixuid/vfs_unixuid.c b/source4/ntvfs/unixuid/vfs_unixuid.c
index 061b8fbe55..9afb2b1380 100644
--- a/source4/ntvfs/unixuid/vfs_unixuid.c
+++ b/source4/ntvfs/unixuid/vfs_unixuid.c
@@ -639,6 +639,7 @@ NTSTATUS ntvfs_unixuid_init(void)
 {
 	NTSTATUS ret;
 	struct ntvfs_ops ops;
+	NTVFS_CURRENT_CRITICAL_SIZES(vers);
 
 	ZERO_STRUCT(ops);
 
@@ -679,15 +680,15 @@ NTSTATUS ntvfs_unixuid_init(void)
 
 	/* we register under all 3 backend types, as we are not type specific */
 	ops.type = NTVFS_DISK;	
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 	if (!NT_STATUS_IS_OK(ret)) goto failed;
 
 	ops.type = NTVFS_PRINT;	
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 	if (!NT_STATUS_IS_OK(ret)) goto failed;
 
 	ops.type = NTVFS_IPC;	
-	ret = ntvfs_register(&ops);
+	ret = ntvfs_register(&ops, &vers);
 	if (!NT_STATUS_IS_OK(ret)) goto failed;
 	
 failed: