/* * 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 3 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, see <http://www.gnu.org/licenses/>. */ #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 FAMChanged: ne.action = NOTIFY_ACTION_MODIFIED; break; 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); }