r21527: Add forgotten notify fam module -- thanks James for the heads-up

diff --git a/source/modules/vfs_notify_fam.c b/source/modules/vfs_notify_fam.c
new file mode 100644 (file)
index 0000000..b76046b
--- /dev/null
+++ b/source/modules/vfs_notify_fam.c
@@ -0,0 +1,302 @@
+/*
+ * FAM file notification support.
+ *
+ * Copyright (c) James Peach 2005
+ * Copyright (c) Volker Lendecke 2007
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include "includes.h"
+
+#include <fam.h>
+
+#if !defined(HAVE_FAM_H_FAMCODES_TYPEDEF)
+/* Gamin provides this typedef which means we can't use 'enum FAMCodes' as per
+ * every other FAM implementation. Phooey.
+ */
+typedef enum FAMCodes FAMCodes;
+#endif
+
+/* NOTE: There are multiple versions of FAM floating around the net, each with
+ * slight differences from the original SGI FAM implementation. In this file,
+ * we rely only on the SGI features and do not assume any extensions. For
+ * example, we do not look at FAMErrno, because it is not set by the original
+ * implementation.
+ *
+ * Random FAM links:
+ *     http://oss.sgi.com/projects/fam/
+ *     http://savannah.nongnu.org/projects/fam/
+ *     http://sourceforge.net/projects/bsdfam/
+ */
+
+/* ------------------------------------------------------------------------- */
+
+struct fam_watch_context {
+       struct fam_watch_context *prev, *next;
+       FAMConnection *fam_connection;
+       struct FAMRequest fr;
+       struct sys_notify_context *sys_ctx;
+       void (*callback)(struct sys_notify_context *ctx, 
+                        void *private_data,
+                        struct notify_event *ev);
+       void *private_data;
+       uint32_t mask; /* the inotify mask */
+       uint32_t filter; /* the windows completion filter */
+       const char *path;
+};
+
+
+/*
+ * We want one FAM connection per smbd, not one per tcon.
+ */
+static FAMConnection fam_connection;
+static BOOL fam_connection_initialized = False;
+
+static struct fam_watch_context *fam_notify_list;
+static void fam_handler(struct event_context *event_ctx,
+                       struct fd_event *fd_event,
+                       uint16 flags,
+                       void *private_data);
+
+static NTSTATUS fam_open_connection(FAMConnection *fam_conn,
+                                   struct event_context *event_ctx)
+{
+       int res;
+       char *name;
+
+       ZERO_STRUCTP(fam_conn);
+       FAMCONNECTION_GETFD(fam_conn) = -1;
+
+       if (asprintf(&name, "smbd (%lu)", (unsigned long)sys_getpid()) == -1) {
+               DEBUG(0, ("No memory\n"));
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       res = FAMOpen2(fam_conn, name);
+       SAFE_FREE(name);
+
+       if (res < 0) {
+               DEBUG(10, ("FAM file change notifications not available\n"));
+               /*
+                * No idea how to get NT_STATUS from a FAM result
+                */
+               FAMCONNECTION_GETFD(fam_conn) = -1;
+               return NT_STATUS_UNEXPECTED_IO_ERROR;
+       }
+
+       if (event_add_fd(event_ctx, event_ctx,
+                        FAMCONNECTION_GETFD(fam_conn),
+                        EVENT_FD_READ, fam_handler,
+                        (void *)fam_conn) == NULL) {
+               DEBUG(0, ("event_add_fd failed\n"));
+               FAMClose(fam_conn);
+               FAMCONNECTION_GETFD(fam_conn) = -1;
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       return NT_STATUS_OK;
+}
+
+static void fam_reopen(FAMConnection *fam_conn,
+                      struct event_context *event_ctx,
+                      struct fam_watch_context *notify_list)
+{
+       struct fam_watch_context *ctx;
+
+       DEBUG(5, ("Re-opening FAM connection\n"));
+
+       FAMClose(fam_conn);
+
+       if (!NT_STATUS_IS_OK(fam_open_connection(fam_conn, event_ctx))) {
+               DEBUG(5, ("Re-opening fam connection failed\n"));
+               return;
+       }
+
+       for (ctx = notify_list; ctx; ctx = ctx->next) {
+               FAMMonitorDirectory(fam_conn, ctx->path, &ctx->fr, NULL);
+       }
+}
+
+static void fam_handler(struct event_context *event_ctx,
+                       struct fd_event *fd_event,
+                       uint16 flags,
+                       void *private_data)
+{
+       FAMConnection *fam_conn = (FAMConnection *)private_data;
+       FAMEvent fam_event;
+       struct fam_watch_context *ctx;
+       struct notify_event ne;
+
+       if (FAMPending(fam_conn) == 0) {
+               DEBUG(10, ("fam_handler called but nothing pending\n"));
+               return;
+       }
+
+       if (FAMNextEvent(fam_conn, &fam_event) != 1) {
+               DEBUG(5, ("FAMNextEvent returned an error\n"));
+               TALLOC_FREE(fd_event);
+               fam_reopen(fam_conn, event_ctx, fam_notify_list);
+               return;
+       }
+
+       DEBUG(10, ("Got FAMCode %d for %s\n", fam_event.code,
+                  fam_event.filename));
+
+       switch (fam_event.code) {
+       case FAMCreated:
+               ne.action = NOTIFY_ACTION_ADDED;
+               break;
+       case FAMDeleted:
+               ne.action = NOTIFY_ACTION_REMOVED;
+               break;
+       default:
+               DEBUG(10, ("Ignoring code FAMCode %d for file %s\n",
+                          (int)fam_event.code, fam_event.filename));
+               return;
+       }
+
+       for (ctx = fam_notify_list; ctx; ctx = ctx->next) {
+               if (memcmp(&fam_event.fr, &ctx->fr, sizeof(FAMRequest)) == 0) {
+                       break;
+               }
+       }
+
+       if (ctx == NULL) {
+               DEBUG(5, ("Discarding event for file %s\n",
+                         fam_event.filename));
+               return;
+       }
+
+       if ((ne.path = strrchr_m(fam_event.filename, '\\')) == NULL) {
+               ne.path = fam_event.filename;
+       }
+
+       ctx->callback(ctx->sys_ctx, ctx->private_data, &ne);
+}
+
+static int fam_watch_context_destructor(struct fam_watch_context *ctx)
+{
+       if (FAMCONNECTION_GETFD(ctx->fam_connection) != -1) {
+               FAMCancelMonitor(&fam_connection, &ctx->fr);
+       }
+       DLIST_REMOVE(fam_notify_list, ctx);
+       return 0;
+}
+
+/*
+  add a watch. The watch is removed when the caller calls
+  talloc_free() on *handle
+*/
+static NTSTATUS fam_watch(vfs_handle_struct *vfs_handle,
+                         struct sys_notify_context *ctx,
+                         struct notify_entry *e,
+                         void (*callback)(struct sys_notify_context *ctx, 
+                                          void *private_data,
+                                          struct notify_event *ev),
+                         void *private_data, 
+                         void *handle_p)
+{
+       const uint32 fam_mask = (FILE_NOTIFY_CHANGE_FILE_NAME|
+                                FILE_NOTIFY_CHANGE_DIR_NAME);
+       struct fam_watch_context *watch;
+       void **handle = (void **)handle_p;
+
+       if ((e->filter & fam_mask) == 0) {
+               DEBUG(10, ("filter = %u, ignoring in FAM\n", e->filter));
+               return NT_STATUS_OK;
+       }
+
+       if (!fam_connection_initialized) {
+               if (!NT_STATUS_IS_OK(fam_open_connection(&fam_connection,
+                                                        ctx->ev))) {
+                       /*
+                        * Just let smbd do all the work itself
+                        */
+                       return NT_STATUS_OK;
+               }
+               fam_connection_initialized = True;
+       }
+
+       if (!(watch = TALLOC_P(ctx, struct fam_watch_context))) {
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       watch->fam_connection = &fam_connection;
+
+       watch->callback = callback;
+       watch->private_data = private_data;
+       watch->sys_ctx = ctx;
+
+       if (!(watch->path = talloc_strdup(watch, e->path))) {
+               DEBUG(0, ("talloc_asprintf failed\n"));
+               TALLOC_FREE(watch);
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       /*
+        * The FAM module in this early state will only take care of
+        * FAMCreated and FAMDeleted events, Leave the rest to
+        * notify_internal.c
+        */
+
+       watch->filter = fam_mask;
+       e->filter &= ~fam_mask;
+
+       DLIST_ADD(fam_notify_list, watch);
+       talloc_set_destructor(watch, fam_watch_context_destructor);
+
+       /*
+        * Only directories monitored so far
+        */
+
+       if (FAMCONNECTION_GETFD(watch->fam_connection) != -1) {
+               FAMMonitorDirectory(watch->fam_connection, watch->path,
+                                   &watch->fr, NULL);
+       }
+       else {
+               /*
+                * If the re-open is successful, this will establish the
+                * FAMMonitor from the list
+                */
+               fam_reopen(watch->fam_connection, ctx->ev, fam_notify_list);
+       }
+
+       *handle = (void *)watch;
+
+       return NT_STATUS_OK;
+}
+
+/* VFS operations structure */
+
+static vfs_op_tuple notify_fam_op_tuples[] = {
+
+       {SMB_VFS_OP(fam_watch),
+        SMB_VFS_OP_NOTIFY_WATCH,
+        SMB_VFS_LAYER_OPAQUE},
+
+       {SMB_VFS_OP(NULL),
+        SMB_VFS_OP_NOOP,
+        SMB_VFS_LAYER_NOOP}
+
+};
+
+
+NTSTATUS vfs_notify_fam_init(void);
+NTSTATUS vfs_notify_fam_init(void)
+{
+       return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "notify_fam",
+                               notify_fam_op_tuples);
+}