Fixed change notify for Visual C++.

No-one seemed to have noticed it wasn't working (this worries
me....).

ChangeNotify now scans the directory if necessary and uses the
sum of all timestamps and the number of entries as the 'hash'
to determin if anything changed.

Jeremy.

1 files changed, 118 insertions, 28 deletions

diff --git a/source/smbd/nttrans.c b/source/smbd/nttrans.c
index d7a9d447d78..9173a977e12 100644
--- a/source/smbd/nttrans.c
+++ b/source/smbd/nttrans.c
@@ -1186,6 +1186,18 @@ static int call_nt_transact_rename(connection_struct *conn,
 }
    
 /****************************************************************************
+ This is the structure to keep the information needed to
+ determine if a directory has changed.
+*****************************************************************************/
+
+typedef struct {
+  time_t modify_time; /* Info from the directory we're monitoring. */ 
+  time_t status_time; /* Info from the directory we're monitoring. */
+  time_t total_time; /* Total time of all directory entries - don't care if it wraps. */
+  unsigned int num_entries; /* Zero or the number of files in the directory. */
+} change_hash_data;
+
+/****************************************************************************
  This is the structure to queue to implement NT change
  notify. It consists of smb_size bytes stored from the
  transact command (to keep the mid, tid etc around).
@@ -1196,9 +1208,9 @@ typedef struct {
   ubi_slNode msg_next;
   files_struct *fsp;
   connection_struct *conn;
+  uint32 flags;
   time_t next_check_time;
-  time_t modify_time; /* Info from the directory we're monitoring. */ 
-  time_t status_time; /* Info from the directory we're monitoring. */
+  change_hash_data change_data;
   char request_buf[smb_size];
 } change_notify_buf;
 
@@ -1239,8 +1251,93 @@ static void change_notify_reply_packet(char *inbuf, int error_class, uint32 erro
 }
 
 /****************************************************************************
+ Create the hash we will use to determine if the contents changed.
+*****************************************************************************/
+
+static BOOL create_directory_notify_hash( change_notify_buf *cnbp, change_hash_data *change_data)
+{
+  SMB_STRUCT_STAT st;
+  files_struct *fsp = cnbp->fsp;
+
+  memset((char *)change_data, '\0', sizeof(change_data));
+
+  /* 
+   * Store the current timestamp on the directory we are monitoring.
+   */
+
+  if(dos_stat(fsp->fsp_name, &st) < 0) {
+    DEBUG(0,("create_directory_notify_hash: Unable to stat name = %s. \
+Error was %s\n", fsp->fsp_name, strerror(errno) ));
+    return False;
+  }
+ 
+  change_data->modify_time = st.st_mtime;
+  change_data->status_time = st.st_ctime;
+
+  /*
+   * If we are to watch for changes that are only stored
+   * in inodes of files, not in the directory inode, we must
+   * scan the directory and produce a unique identifier with
+   * which we can determine if anything changed. We use the
+   * modify and change times from all the files in the
+   * directory, added together (ignoring wrapping if it's
+   * larger than the max time_t value).
+   */
+
+  if(cnbp->flags & (FILE_NOTIFY_CHANGE_SIZE|FILE_NOTIFY_CHANGE_LAST_WRITE)) {
+    pstring full_name;
+    char *p;
+    char *fname;
+    char *fname_off;
+    size_t remaining_len;
+    size_t fullname_len;
+    void *dp = OpenDir(cnbp->conn, fsp->fsp_name, True);
+
+    if(dp == NULL) {
+      DEBUG(0,("create_directory_notify_hash: Unable to open directory = %s. \
+Error was %s\n", fsp->fsp_name, strerror(errno) ));
+      return False;
+    }
+
+    change_data->num_entries = 0;
+
+    pstrcpy(full_name, fsp->fsp_name);
+    pstrcat(full_name, "/");
+
+    fullname_len = strlen(full_name);
+    remaining_len = sizeof(full_name) - fullname_len - 1;
+    p = &full_name[fullname_len];
+
+    while(fname = ReadDirName( dp )) {
+      if(strequal(fname, ".") || strequal(fname, ".."))
+        continue;
+
+      change_data->num_entries++;
+      safe_strcpy( p, fname, remaining_len);
+
+      memset(&st, '\0', sizeof(st));
+
+      /*
+       * Do the stat - but ignore errors.
+       */
+
+      if(dos_stat(full_name, &st) < 0) {
+        DEBUG(5,("create_directory_notify_hash: Unable to stat content file = %s. \
+Error was %s\n", fsp->fsp_name, strerror(errno) ));
+      }
+      change_data->total_time += (st.st_mtime + st.st_ctime);
+    }
+
+    CloseDir(dp);
+  }
+
+  return True;
+}
+
+/****************************************************************************
  Delete entries by fnum from the change notify pending queue.
 *****************************************************************************/
+
 void remove_pending_change_notify_requests_by_fid(files_struct *fsp)
 {
   change_notify_buf *cnbp = (change_notify_buf *)ubi_slFirst( &change_notify_queue );
@@ -1301,8 +1398,7 @@ void process_pending_change_notify_queue(time_t t)
    */
 
   while((cnbp != NULL) && (cnbp->next_check_time <= t)) {
-    SMB_STRUCT_STAT st;
-    files_struct *fsp = cnbp->fsp;
+    change_hash_data change_data;
     connection_struct *conn = cnbp->conn;
     uint16 vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID : 
                   SVAL(cnbp->request_buf,smb_uid);
@@ -1338,9 +1434,9 @@ void process_pending_change_notify_queue(time_t t)
       continue;
     }
 
-    if(dos_stat(fsp->fsp_name, &st) < 0) {
-      DEBUG(0,("process_pending_change_notify_queue: Unable to stat directory %s. \
-Error was %s.\n", fsp->fsp_name, strerror(errno) ));
+    if(!create_directory_notify_hash( cnbp, &change_data)) {
+      DEBUG(0,("process_pending_change_notify_queue: Unable to create change data for \
+directory %s\n", cnbp->fsp->fsp_name ));
       /*
        * Remove the entry and return an error to the client.
        */
@@ -1351,13 +1447,12 @@ Error was %s.\n", fsp->fsp_name, strerror(errno) ));
       continue;
     }
 
-    if(cnbp->modify_time != st.st_mtime ||
-       cnbp->status_time != st.st_ctime) {
+    if(memcmp( (char *)&cnbp->change_data, (char *)&change_data, sizeof(change_data))) {
       /*
        * Remove the entry and return a change notify to the client.
        */
-      DEBUG(5,("process_pending_change_notify_queue: directory name = %s changed\n",
-            fsp->fsp_name ));
+      DEBUG(5,("process_pending_change_notify_queue: directory name = %s changed.\n",
+            cnbp->fsp->fsp_name ));
       change_notify_reply_packet(cnbp->request_buf,0,NT_STATUS_NOTIFY_ENUM_DIR);
       free((char *)ubi_slRemNext( &change_notify_queue, prev));
       cnbp = (change_notify_buf *)(prev ? ubi_slNext(prev) : ubi_slFirst(&change_notify_queue));
@@ -1379,16 +1474,16 @@ Error was %s.\n", fsp->fsp_name, strerror(errno) ));
  Reply to a notify change - queue the request and 
  don't allow a directory to be opened.
 ****************************************************************************/
+
 static int call_nt_transact_notify_change(connection_struct *conn,
-					  char *inbuf, char *outbuf, int length,
+                                          char *inbuf, char *outbuf, int length,
                                           int bufsize, 
                                           char **ppsetup, 
-					  char **ppparams, char **ppdata)
+                                          char **ppparams, char **ppdata)
 {
   char *setup = *ppsetup;
   files_struct *fsp;
   change_notify_buf *cnbp;
-  SMB_STRUCT_STAT st;
 
   fsp = file_fsp(setup,4);
 
@@ -1409,28 +1504,22 @@ static int call_nt_transact_notify_change(connection_struct *conn,
    */
 
   if((cnbp = (change_notify_buf *)malloc(sizeof(change_notify_buf))) == NULL) {
-    DEBUG(0,("call_nt_transact_notify_change: Malloc fail (2) !\n" ));
+    DEBUG(0,("call_nt_transact_notify_change: malloc fail !\n" ));
     return -1;
   }
 
-  /* 
-   * Store the current timestamp on the directory we are monitoring.
-   */
+  memset((char *)cnbp, '\0', sizeof(change_notify_buf));
 
-  if(dos_stat(fsp->fsp_name, &st) < 0) {
-    DEBUG(0,("call_nt_transact_notify_change: Unable to stat name = %s. \
-Error was %s\n", fsp->fsp_name, strerror(errno) ));
-    free((char *)cnbp);
-    return(UNIXERROR(ERRDOS,ERRbadfid));
-  }
- 
   memcpy(cnbp->request_buf, inbuf, smb_size);
   cnbp->fsp = fsp;
   cnbp->conn = conn;
-  cnbp->modify_time = st.st_mtime;
-  cnbp->status_time = st.st_ctime;
-
   cnbp->next_check_time = time(NULL) + lp_change_notify_timeout();
+  cnbp->flags = IVAL(setup, 0);
+
+  if(!create_directory_notify_hash( cnbp, &cnbp->change_data )) {
+    free((char *)cnbp);
+    return(UNIXERROR(ERRDOS,ERRbadfid));
+  }
 
   /*
    * Adding to the tail enables us to check only
@@ -1450,6 +1539,7 @@ name = %s\n", fsp->fsp_name ));
  Reply to query a security descriptor - currently this is not implemented (it
  is planned to be though).
 ****************************************************************************/
+
 static int call_nt_transact_query_security_desc(connection_struct *conn,
 						char *inbuf, char *outbuf, 
 						int length,