server: Track created and removed directories in the tree of inodes for inotify.
Add them to or remove them from existing recursive watches.
diff --git a/server/change.c b/server/change.c
index d0de942..e1093d6 100644
--- a/server/change.c
+++ b/server/change.c
@@ -152,6 +152,7 @@
int notified; /* SIGIO counter */
int want_data; /* return change data */
long signaled; /* the file changed */
+ int subtree; /* do we want to watch subdirectories? */
struct list change_q; /* change readers */
struct list change_records; /* data for the change */
struct list in_entry; /* entry in the inode dirs list */
@@ -388,17 +389,23 @@
#define HASH_SIZE 31
struct inode {
+ struct list ch_entry; /* entry in the children list */
+ struct list children; /* children of this inode */
+ struct inode *parent; /* parent of this inode */
struct list dirs; /* directory handles watching this inode */
struct list ino_entry; /* entry in the inode hash */
struct list wd_entry; /* entry in the watch descriptor hash */
dev_t dev; /* device number */
ino_t ino; /* device's inode number */
int wd; /* inotify's watch descriptor */
+ char *name; /* basename name of the inode */
};
struct list inode_hash[ HASH_SIZE ];
struct list wd_hash[ HASH_SIZE ];
+static int inotify_add_dir( char *path, unsigned int filter );
+
static struct inode *inode_from_wd( int wd )
{
struct list *bucket = &wd_hash[ wd % HASH_SIZE ];
@@ -416,7 +423,7 @@
return &inode_hash[ (ino ^ dev) % HASH_SIZE ];
}
-static struct inode *get_inode( dev_t dev, ino_t ino )
+static struct inode *find_inode( dev_t dev, ino_t ino )
{
struct list *bucket = get_hash_list( dev, ino );
struct inode *inode;
@@ -435,15 +442,28 @@
inode = malloc( sizeof *inode );
if (inode)
{
+ list_init( &inode->children );
list_init( &inode->dirs );
inode->ino = ino;
inode->dev = dev;
inode->wd = -1;
+ inode->parent = NULL;
+ inode->name = NULL;
list_add_tail( get_hash_list( dev, ino ), &inode->ino_entry );
}
return inode;
}
+static struct inode *get_inode( dev_t dev, ino_t ino )
+{
+ struct inode *inode;
+
+ inode = find_inode( dev, ino );
+ if (inode)
+ return inode;
+ return create_inode( dev, ino );
+}
+
static void inode_set_wd( struct inode *inode, int wd )
{
if (inode->wd != -1)
@@ -452,20 +472,83 @@
list_add_tail( &wd_hash[ wd % HASH_SIZE ], &inode->wd_entry );
}
+static void inode_set_name( struct inode *inode, const char *name )
+{
+ if (inode->name)
+ free (inode->name);
+ inode->name = name ? strdup( name ) : NULL;
+}
+
static void free_inode( struct inode *inode )
{
- if (!list_empty( &inode->dirs ))
+ int subtree = 0, watches = 0;
+ struct dir *dir;
+
+ LIST_FOR_EACH_ENTRY( dir, &inode->dirs, struct dir, in_entry )
+ {
+ subtree |= dir->subtree;
+ watches++;
+ }
+
+ if (!subtree && !inode->parent)
+ {
+ struct list *head;
+ while ( (head = list_head(&inode->children)) )
+ {
+ struct inode *tmp = LIST_ENTRY( head, struct inode, ch_entry );
+ assert( tmp != inode );
+ assert( tmp->parent == inode );
+ free_inode( tmp );
+ }
+ }
+
+ if (watches)
return;
+ if (inode->parent)
+ list_remove( &inode->ch_entry );
+
if (inode->wd != -1)
{
inotify_remove_watch( get_unix_fd( inotify_fd ), inode->wd );
list_remove( &inode->wd_entry );
}
list_remove( &inode->ino_entry );
+
+ free( inode->name );
free( inode );
}
+static struct inode *inode_add( struct inode *parent,
+ dev_t dev, ino_t ino, const char *name )
+{
+ struct inode *inode;
+
+ inode = get_inode( dev, ino );
+ if (!inode)
+ return NULL;
+
+ if (!inode->parent)
+ {
+ list_add_tail( &parent->children, &inode->ch_entry );
+ inode->parent = parent;
+ assert( inode != parent );
+ }
+ inode_set_name( inode, name );
+
+ return inode;
+}
+
+static struct inode *inode_from_name( struct inode *inode, const char *name )
+{
+ struct inode *i;
+
+ LIST_FOR_EACH_ENTRY( i, &inode->children, struct inode, ch_entry )
+ if (i->name && !strcmp( i->name, name ))
+ return i;
+ return NULL;
+}
+
static int inotify_get_poll_events( struct fd *fd );
static void inotify_poll_event( struct fd *fd, int event );
static int inotify_get_info( struct fd *fd );
@@ -490,6 +573,8 @@
{
struct change_record *record;
+ assert( dir->obj.ops == &dir_ops );
+
if (dir->want_data)
{
size_t len = strlen(relpath);
@@ -531,38 +616,134 @@
return filter;
}
-static int inode_entry_is_dir( struct inode *inode, const char *name )
+/* scan up the parent directories for watches */
+static unsigned int filter_from_inode( struct inode *inode, int is_parent )
{
- /* distinguish a created file from a directory */
- char *path;
+ unsigned int filter = 0;
+ struct dir *dir;
+
+ /* combine filters from parents watching subtrees */
+ while (inode)
+ {
+ LIST_FOR_EACH_ENTRY( dir, &inode->dirs, struct dir, in_entry )
+ if (dir->subtree || !is_parent)
+ filter |= dir->filter;
+ is_parent = 1;
+ inode = inode->parent;
+ }
+
+ return filter;
+}
+
+static char *inode_get_path( struct inode *inode, int sz )
+{
struct list *head;
- struct stat st;
- int unix_fd, r;
+ char *path;
+ int len;
+
+ if (!inode)
+ return NULL;
head = list_head( &inode->dirs );
- if (!head)
- return -1;
+ if (head)
+ {
+ int unix_fd = get_unix_fd( LIST_ENTRY( head, struct dir, in_entry )->fd );
+ path = malloc ( 32 + sz );
+ if (path)
+ sprintf( path, "/proc/self/fd/%u/", unix_fd );
+ return path;
+ }
- path = malloc( strlen(name) + 32 );
+ if (!inode->name)
+ return NULL;
+
+ len = strlen( inode->name );
+ path = inode_get_path( inode->parent, sz + len + 1 );
if (!path)
- return -1;
+ return NULL;
+
+ strcat( path, inode->name );
+ strcat( path, "/" );
- unix_fd = get_unix_fd( LIST_ENTRY( head, struct dir, in_entry )->fd );
- sprintf( path, "/proc/self/fd/%u/%s", unix_fd, name );
+ return path;
+}
+
+static int inode_check_dir( struct inode *parent, const char *name )
+{
+ char *path;
+ unsigned int filter;
+ struct inode *inode;
+ struct stat st;
+ int wd = -1, r = -1;
+
+ path = inode_get_path( parent, strlen(name) );
+ if (!path)
+ return r;
+
+ strcat( path, name );
+
r = stat( path, &st );
- free( path );
- if (-1 == r)
- return -1;
+ if (r < 0) goto end;
- if (S_ISDIR(st.st_mode))
- return 1;
- return 0;
+ if (!S_ISDIR(st.st_mode))
+ {
+ r = 0;
+ goto end;
+ }
+
+ r = 1;
+
+ filter = filter_from_inode( parent, 1 );
+ if (!filter)
+ goto end;
+
+ inode = inode_add( parent, st.st_dev, st.st_ino, name );
+ if (!inode || inode->wd != -1)
+ goto end;
+
+ wd = inotify_add_dir( path, filter );
+ if (wd != -1)
+ inode_set_wd( inode, wd );
+ else
+ free_inode( inode );
+
+end:
+ free( path );
+ return r;
+}
+
+static int prepend( char **path, const char *segment )
+{
+ int extra;
+ char *p;
+
+ extra = strlen( segment ) + 1;
+ if (*path)
+ {
+ int len = strlen( *path ) + 1;
+ p = realloc( *path, len + extra );
+ if (!p) return 0;
+ memmove( &p[ extra ], p, len );
+ p[ extra - 1 ] = '/';
+ memcpy( p, segment, extra - 1 );
+ }
+ else
+ {
+ p = malloc( extra );
+ if (!p) return 0;
+ memcpy( p, segment, extra );
+ }
+
+ *path = p;
+
+ return 1;
}
static void inotify_notify_all( struct inotify_event *ie )
{
unsigned int filter, action;
- struct inode *inode;
+ struct inode *inode, *i;
+ char *path = NULL;
struct dir *dir;
inode = inode_from_wd( ie->wd );
@@ -576,7 +757,7 @@
if (ie->mask & IN_CREATE)
{
- switch (inode_entry_is_dir( inode, ie->name ))
+ switch (inode_check_dir( inode, ie->name ))
{
case 1:
filter &= ~FILE_NOTIFY_CHANGE_FILE_NAME;
@@ -595,9 +776,32 @@
else
action = FILE_ACTION_MODIFIED;
- LIST_FOR_EACH_ENTRY( dir, &inode->dirs, struct dir, in_entry )
- if (filter & dir->filter)
- inotify_do_change_notify( dir, action, ie->name );
+ /*
+ * Work our way up the inode heirachy
+ * extending the relative path as we go
+ * and notifyiny all recursive watches.
+ */
+ if (!prepend( &path, ie->name ))
+ return;
+
+ for (i = inode; i; i = i->parent)
+ {
+ LIST_FOR_EACH_ENTRY( dir, &i->dirs, struct dir, in_entry )
+ if ((filter & dir->filter) && (i==inode || dir->subtree))
+ inotify_do_change_notify( dir, action, path );
+
+ if (!i->name || !prepend( &path, i->name ))
+ break;
+ }
+
+ free( path );
+
+ if (ie->mask & IN_DELETE)
+ {
+ i = inode_from_name( inode, ie->name );
+ if (i)
+ free_inode( i );
+ }
}
static void inotify_poll_event( struct fd *fd, int event )
@@ -642,12 +846,11 @@
static int map_flags( unsigned int filter )
{
- unsigned int mask = 0;
+ unsigned int mask;
- if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
- mask |= (IN_MOVED_FROM | IN_MOVED_TO | IN_DELETE | IN_CREATE);
- if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
- mask |= (IN_MOVED_FROM | IN_MOVED_TO | IN_DELETE | IN_CREATE | IN_DELETE_SELF);
+ /* always watch these so we can track subdirectories in recursive watches */
+ mask = (IN_MOVED_FROM | IN_MOVED_TO | IN_DELETE | IN_CREATE | IN_DELETE_SELF);
+
if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
mask |= IN_ATTRIB;
if (filter & FILE_NOTIFY_CHANGE_SIZE)
@@ -656,8 +859,6 @@
mask |= IN_MODIFY;
if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
mask |= IN_ACCESS;
- if (filter & FILE_NOTIFY_CHANGE_CREATION)
- mask |= IN_CREATE;
if (filter & FILE_NOTIFY_CHANGE_SECURITY)
mask |= IN_ATTRIB;
@@ -673,17 +874,6 @@
return wd;
}
-static unsigned int filter_from_inode( struct inode *inode )
-{
- unsigned int filter = 0;
- struct dir *dir;
-
- LIST_FOR_EACH_ENTRY( dir, &inode->dirs, struct dir, in_entry )
- filter |= dir->filter;
-
- return filter;
-}
-
static int init_inotify( void )
{
int i;
@@ -733,7 +923,7 @@
dir->inode = inode;
}
- filter = filter_from_inode( inode );
+ filter = filter_from_inode( inode, 0 );
sprintf( path, "/proc/self/fd/%u", unix_fd );
wd = inotify_add_dir( path, filter );
@@ -825,6 +1015,7 @@
init_inotify();
insert_change( dir );
dir->filter = req->filter;
+ dir->subtree = req->subtree;
dir->want_data = req->want_data;
}
