fs:notify add support for inotify

support API: open close read write unlink mkdir rename fchstat rmdir symlink

Signed-off-by: guohao15 <guohao15@xiaomi.com>

fs/Kconfig

@@ -118,6 +118,7 @@ source "fs/mqueue/Kconfig"
 source "fs/shm/Kconfig"
 source "fs/mmap/Kconfig"
 source "fs/partition/Kconfig"
+source "fs/notify/Kconfig"
 source "fs/fat/Kconfig"
 source "fs/nfs/Kconfig"
 source "fs/nxffs/Kconfig"

fs/Makefile

@@ -59,6 +59,7 @@ include rpmsgfs/Make.defs
 include zipfs/Make.defs
 include mnemofs/Make.defs
 include v9fs/Make.defs
+include notify/Make.defs
 endif
 
 CFLAGS += ${INCDIR_PREFIX}$(TOPDIR)$(DELIM)fs

fs/driver/fs_registerblockdriver.c

@@ -30,6 +30,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 #ifndef CONFIG_DISABLE_MOUNTPOINT
 
@@ -90,7 +91,11 @@ int register_blockdriver(FAR const char *path,
 
       node->u.i_bops  = bops;
       node->i_private = priv;
-      ret             = OK;
+      inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_create(path);
+#endif
+      return OK;
     }
 
   inode_unlock();

fs/driver/fs_registerdriver.c

@@ -31,6 +31,7 @@
 #include <nuttx/sched_note.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Public Functions
@@ -89,7 +90,11 @@ int register_driver(FAR const char *path,
 
       node->u.i_ops   = fops;
       node->i_private = priv;
-      ret             = OK;
+      inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_create(path);
+#endif
+      return OK;
     }
 
   inode_unlock();

fs/driver/fs_registermtddriver.c

@@ -31,6 +31,7 @@
 #include <nuttx/mtd/mtd.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 #if defined(CONFIG_MTD) && !defined(CONFIG_DISABLE_MOUNTPOINT)
 
@@ -90,7 +91,11 @@ int register_mtddriver(FAR const char *path, FAR struct mtd_dev_s *mtd,
 
       node->u.i_mtd   = mtd;
       node->i_private = priv;
-      ret             = OK;
+      inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_create(path);
+#endif
+      return OK;
     }
 
   inode_unlock();

fs/driver/fs_registerpipedriver.c

@@ -30,6 +30,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 #ifdef CONFIG_PIPES
 
@@ -88,7 +89,11 @@ int register_pipedriver(FAR const char *path,
 
       node->u.i_ops   = fops;
       node->i_private = priv;
-      ret             = OK;
+      inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_create(path);
+#endif
+      return OK;
     }
 
   inode_unlock();

fs/driver/fs_unregisterblockdriver.c

@@ -27,6 +27,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Public Functions
@@ -49,7 +50,12 @@ int unregister_blockdriver(FAR const char *path)
     {
       ret = inode_remove(path);
       inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_unlink(path);
+#endif
+      return OK;
     }
 
+  inode_unlock();
   return ret;
 }

fs/driver/fs_unregisterdriver.c

@@ -27,6 +27,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Public Functions
@@ -59,7 +60,12 @@ int unregister_driver(FAR const char *path)
     {
       ret = inode_remove(path);
       inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_unlink(path);
+#endif
+      return OK;
     }
 
+  inode_unlock();
   return ret;
 }

fs/driver/fs_unregistermtddriver.c

@@ -28,6 +28,7 @@
 #include <nuttx/mtd/mtd.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Public Functions
@@ -50,7 +51,12 @@ int unregister_mtddriver(FAR const char *path)
     {
       ret = inode_remove(path);
       inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_unlink(path);
+#endif
+      return OK;
     }
 
+  inode_unlock();
   return ret;
 }

fs/driver/fs_unregisterpipedriver.c

@@ -27,6 +27,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 #ifdef CONFIG_PIPES
 
@@ -51,8 +52,13 @@ int unregister_pipedriver(FAR const char *path)
     {
       ret = inode_remove(path);
       inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+      notify_unlink(path);
+#endif
+      return OK;
     }
 
+  inode_unlock();
   return ret;
 }
 

fs/fs_initialize.c

@@ -26,6 +26,7 @@
 #include <nuttx/reboot_notifier.h>
 #include <nuttx/trace.h>
 
+#include "notify/notify.h"
 #include "rpmsgfs/rpmsgfs.h"
 #include "inode/inode.h"
 #include "aio/aio.h"
@@ -97,6 +98,10 @@ void fs_initialize(void)
   rpmsgfs_server_init();
 #endif
 
+#ifdef CONFIG_FS_NOTIFY
+  notify_initialize();
+#endif
+
   register_reboot_notifier(&g_sync_nb);
   fs_trace_end();
 }

fs/mount/fs_mount.c

@@ -33,8 +33,9 @@
 
 #include <nuttx/fs/fs.h>
 
-#include "inode/inode.h"
 #include "driver/driver.h"
+#include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Pre-processor Definitions
@@ -494,6 +495,9 @@ int nx_mount(FAR const char *source, FAR const char *target,
 
 #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
   RELEASE_SEARCH(&desc);
+#endif
+#ifdef CONFIG_FS_NOTIFY
+  notify_create(target);
 #endif
   return OK;
 

fs/mount/fs_umount2.c

@@ -32,6 +32,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Public Functions
@@ -184,6 +185,9 @@ int nx_umount2(FAR const char *target, unsigned int flags)
     }
 
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_unmount(target);
+#endif
   return OK;
 
   /* A lot of goto's!  But they make the error handling much simpler */

fs/mqueue/mq_open.c

@@ -39,6 +39,7 @@
 
 #include "inode/inode.h"
 #include "mqueue/mqueue.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Private Functions Prototypes
@@ -331,6 +332,9 @@ static int file_mq_vopen(FAR struct file *mq, FAR const char *mq_name,
 
   RELEASE_SEARCH(&desc);
   leave_critical_section(flags);
+#ifdef CONFIG_FS_NOTIFY
+  notify_open(fullpath, oflags);
+#endif
   return OK;
 
 errout_with_inode:

fs/mqueue/mq_unlink.c

@@ -34,6 +34,7 @@
 
 #include "inode/inode.h"
 #include "mqueue/mqueue.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Private Functions
@@ -173,6 +174,9 @@ int file_mq_unlink(FAR const char *mq_name)
   inode_unlock();
   mq_inode_release(inode);
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_unlink(fullpath);
+#endif
   return OK;
 
 errout_with_lock:

fs/notify/Kconfig

@@ -0,0 +1,25 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+config FS_NOTIFY
+	bool "FS Notify System"
+	default n
+	---help---
+		The Fsnotify System
+
+if FS_NOTIFY
+config FSNOTIFY_BUCKET_SIZE
+	int "Dir hash bucket size"
+	default 64
+
+config FSNOTIFY_MAX_EVENTS
+	int "Max events in one notify device"
+	default 1024
+
+config FSNOTIFY_FD_POLLWAITERS
+	int "Max pollwaiters in one notify devcie"
+	default 2
+
+endif # FS_NOTIFY

fs/notify/Make.defs

@@ -0,0 +1,29 @@
+############################################################################
+# fs/notify/Make.defs
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+# Include FSNOTIFY build support
+
+
+ifeq ($(CONFIG_FS_NOTIFY),y)
+CSRCS += inotify.c
+endif
+
+DEPPATH += --dep-path notify
+VPATH += :notify

fs/notify/notify.h

@@ -0,0 +1,58 @@
+/****************************************************************************
+ * fs/notify/notify.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __FS_NOTIFY_NOTIFY_H
+#define __FS_NOTIFY_NOTIFY_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/fs/fs.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Type Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/* These are internal OS interface and are not available to applications */
+
+void notify_open(FAR const char *path, int oflags);
+void notify_close(FAR struct file *filep);
+void notify_close2(FAR struct inode *inode);
+void notify_read(FAR struct file *filep);
+void notify_write(FAR struct file *filep);
+void notify_chstat(FAR struct file *filep);
+void notify_unlink(FAR const char *path);
+void notify_unmount(FAR const char *path);
+void notify_mkdir(FAR const char *path);
+void notify_create(FAR const char *path);
+void notify_rename(FAR const char *oldpath, bool oldisdir,
+                   FAR const char *newpath, bool newisdir);
+void notify_initialize(void);
+
+#endif

fs/semaphore/sem_close.c

@@ -33,6 +33,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 #ifdef CONFIG_FS_NAMED_SEMAPHORES
 
@@ -116,7 +117,9 @@ int nxsem_close(FAR sem_t *sem)
        */
 
       inode_unlock();
-
+#ifdef CONFIG_FS_NOTIFY
+      notify_close2(inode);
+#endif
       DEBUGASSERT(inode->i_peer == NULL);
       inode_free(inode);
       return OK;

fs/semaphore/sem_open.c

@@ -40,6 +40,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 #include "semaphore/semaphore.h"
 
 #ifdef CONFIG_FS_NAMED_SEMAPHORES
@@ -222,6 +223,9 @@ int nxsem_open(FAR sem_t **sem, FAR const char *name, int oflags, ...)
     }
 
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_open(fullpath, oflags);
+#endif
   return OK;
 
 errout_with_inode:

fs/semaphore/sem_unlink.c

@@ -34,6 +34,7 @@
 #include <nuttx/semaphore.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 #include "semaphore/semaphore.h"
 
 /****************************************************************************
@@ -138,6 +139,9 @@ int nxsem_unlink(FAR const char *name)
   inode_unlock();
   ret = nxsem_close(&inode->u.i_nsem->ns_sem);
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_unlink(fullpath);
+#endif
   return ret;
 
 errout_with_lock:

fs/shm/shm_open.c

@@ -29,6 +29,7 @@
 #include <errno.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 #include "shm/shmfs.h"
 
 /****************************************************************************
@@ -149,6 +150,13 @@ errout_with_sem:
   inode_unlock();
 errout_with_search:
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  if (ret >= 0)
+    {
+      notify_open(fullpath, oflags);
+    }
+#endif
+
   return ret;
 }
 

fs/shm/shm_unlink.c

@@ -27,6 +27,7 @@
 #include <errno.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Private Functions
@@ -140,6 +141,13 @@ errout_with_sem:
   inode_unlock();
 errout_with_search:
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  if (ret >= 0)
+    {
+      notify_unlink(fullpath);
+    }
+#endif
+
   return ret;
 }
 

fs/vfs/fs_close.c

@@ -32,6 +32,7 @@
 
 #include <nuttx/fs/fs.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 #include "vfs/lock.h"
 

fs/vfs/fs_fchstat.c

@@ -31,6 +31,7 @@
 
 #include <nuttx/fs/fs.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -191,6 +192,13 @@ int file_fchstat(FAR struct file *filep, FAR struct stat *buf, int flags)
       ret = inode_chstat(inode, buf, flags, 0);
     }
 
+#ifdef CONFIG_FS_NOTIFY
+  if (ret >= 0)
+    {
+      notify_chstat(filep);
+    }
+#endif
+
   return ret;
 }
 

fs/vfs/fs_mkdir.c

@@ -32,6 +32,7 @@
 
 #include <nuttx/fs/fs.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -165,6 +166,9 @@ int mkdir(const char *pathname, mode_t mode)
   /* Directory successfully created */
 
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_mkdir(pathname);
+#endif
   return OK;
 
 errout_with_inode:

fs/vfs/fs_open.c

@@ -38,6 +38,7 @@
 
 #include "inode/inode.h"
 #include "driver/driver.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Private Functions
@@ -196,7 +197,15 @@ static int file_vopen(FAR struct file *filep, FAR const char *path,
 
       /* Get the file structure of the opened character driver proxy */
 
-      return block_proxy(filep, path, oflags);
+      ret = block_proxy(filep, path, oflags);
+#ifdef CONFIG_FS_NOTIFY
+      if (ret >= 0)
+        {
+          notify_open(path, filep->f_oflags);
+        }
+#endif
+
+      return ret;
     }
 #endif
 
@@ -255,6 +264,9 @@ static int file_vopen(FAR struct file *filep, FAR const char *path,
     }
 
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_open(path, filep->f_oflags);
+#endif
   return OK;
 
 errout_with_inode:

fs/vfs/fs_pseudofile.c

@@ -37,6 +37,7 @@
 #include <nuttx/lib/math32.h>
 
 #include "inode/inode.h"
+#include "notify/notify.h"
 
 /****************************************************************************
  * Private Types
@@ -505,6 +506,9 @@ int pseudofile_create(FAR struct inode **node, FAR const char *path,
   (*node)->i_private = pf;
 
   inode_unlock();
+#ifdef CONFIG_FS_NOTIFY
+  notify_create(path);
+#endif
   return 0;
 
 reserve_err:

fs/vfs/fs_read.c

@@ -33,6 +33,7 @@
 
 #include <nuttx/cancelpt.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -96,6 +97,13 @@ ssize_t file_read(FAR struct file *filep, FAR void *buf, size_t nbytes)
 
   /* Return the number of bytes read (or possibly an error code) */
 
+#ifdef CONFIG_FS_NOTIFY
+  if (ret > 0)
+    {
+      notify_read(filep);
+    }
+#endif
+
   return ret;
 }
 

fs/vfs/fs_rename.c

@@ -35,6 +35,7 @@
 #include <nuttx/fs/fs.h>
 #include <nuttx/lib/lib.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -67,6 +68,9 @@ static int pseudorename(FAR const char *oldpath, FAR struct inode *oldinode,
   struct inode_search_s newdesc;
   FAR struct inode *newinode;
   FAR char *subdir = NULL;
+#ifdef CONFIG_FS_NOTIFY
+  bool isdir = INODE_IS_PSEUDODIR(oldinode);
+#endif
   int ret;
 
   /* According to POSIX, any new inode at this path should be removed
@@ -160,6 +164,9 @@ next_subdir:
            */
 
           inode_remove(newpath);
+#ifdef CONFIG_FS_NOTIFY
+          notify_unlink(newpath);
+#endif
         }
 
       inode_release(newinode);
@@ -244,6 +251,13 @@ errout_with_lock:
 
 errout:
   RELEASE_SEARCH(&newdesc);
+#ifdef CONFIG_FS_NOTIFY
+  if (ret >= 0)
+    {
+      notify_rename(oldpath, isdir, newpath, isdir);
+    }
+#endif
+
   if (subdir != NULL)
     {
       lib_free(subdir);
@@ -270,6 +284,10 @@ static int mountptrename(FAR const char *oldpath, FAR struct inode *oldinode,
   FAR struct inode *newinode;
   FAR const char *newrelpath;
   FAR char *subdir = NULL;
+#ifdef CONFIG_FS_NOTIFY
+  bool newisdir = false;
+  bool oldisdir = false;
+#endif
   int ret;
 
   DEBUGASSERT(oldinode->u.i_mops);
@@ -338,13 +356,26 @@ static int mountptrename(FAR const char *oldpath, FAR struct inode *oldinode,
     {
       struct stat buf;
 
+#ifdef CONFIG_FS_NOTIFY
+      ret = oldinode->u.i_mops->stat(oldinode, oldpath, &buf);
+      if (ret >= 0)
+        {
+          oldisdir = S_ISDIR(buf.st_mode);
+        }
+#endif
+
 next_subdir:
       ret = oldinode->u.i_mops->stat(oldinode, newrelpath, &buf);
       if (ret >= 0)
         {
           /* Is the directory entry a directory? */
 
+#ifdef CONFIG_FS_NOTIFY
+          newisdir = S_ISDIR(buf.st_mode);
+          if (newisdir)
+#else
           if (S_ISDIR(buf.st_mode))
+#endif
             {
               FAR char *subdirname;
 
@@ -417,6 +448,9 @@ next_subdir:
                    */
 
                    oldinode->u.i_mops->unlink(oldinode, newrelpath);
+#ifdef CONFIG_FS_NOTIFY
+                   notify_unlink(newrelpath);
+#endif
                 }
             }
         }
@@ -438,6 +472,13 @@ errout_with_newsearch:
       lib_free(subdir);
     }
 
+#ifdef CONFIG_FS_NOTIFY
+  if (ret >= 0)
+    {
+      notify_rename(oldpath, oldisdir, newpath, newisdir);
+    }
+#endif
+
   return ret;
 }
 #endif /* CONFIG_DISABLE_MOUNTPOINT */

fs/vfs/fs_rmdir.c

@@ -31,6 +31,7 @@
 
 #include <nuttx/fs/fs.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -165,6 +166,9 @@ int rmdir(FAR const char *pathname)
 
   inode_release(inode);
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_unlink(pathname);
+#endif
   return OK;
 
 errout_with_inode:

fs/vfs/fs_symlink.c

@@ -35,6 +35,7 @@
 #include <nuttx/lib/lib.h>
 #include <nuttx/fs/fs.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -167,6 +168,9 @@ int symlink(FAR const char *path1, FAR const char *path2)
   /* Symbolic link successfully created */
 
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_create(path2);
+#endif
   return OK;
 
 errout_with_inode:

fs/vfs/fs_unlink.c

@@ -31,6 +31,7 @@
 
 #include <nuttx/fs/fs.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -190,6 +191,9 @@ int nx_unlink(FAR const char *pathname)
 
   inode_release(inode);
   RELEASE_SEARCH(&desc);
+#ifdef CONFIG_FS_NOTIFY
+  notify_unlink(pathname);
+#endif
   return OK;
 
 #if !defined(CONFIG_DISABLE_MOUNTPOINT) || !defined(CONFIG_DISABLE_PSEUDOFS_OPERATIONS)

fs/vfs/fs_write.c

@@ -33,6 +33,7 @@
 
 #include <nuttx/cancelpt.h>
 
+#include "notify/notify.h"
 #include "inode/inode.h"
 
 /****************************************************************************
@@ -68,6 +69,7 @@ ssize_t file_write(FAR struct file *filep, FAR const void *buf,
                    size_t nbytes)
 {
   FAR struct inode *inode;
+  ssize_t ret;
 
   /* Was this file opened for write access? */
 
@@ -86,7 +88,15 @@ ssize_t file_write(FAR struct file *filep, FAR const void *buf,
 
   /* Yes, then let the driver perform the write */
 
-  return inode->u.i_ops->write(filep, buf, nbytes);
+  ret = inode->u.i_ops->write(filep, buf, nbytes);
+#ifdef CONFIG_FS_NOTIFY
+  if (ret > 0)
+    {
+      notify_write(filep);
+    }
+#endif
+
+  return ret;
 }
 
 /****************************************************************************

include/sys/inotify.h

@@ -0,0 +1,169 @@
+/****************************************************************************
+ * include/sys/inotify.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __INCLUDE_SYS_INOTIFY_H
+#define __INCLUDE_SYS_INOTIFY_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <fcntl.h>
+#include <stdint.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define IN_ACCESS        0x00000001      /* File was accessed */
+#define IN_MODIFY        0x00000002      /* File was modified */
+#define IN_ATTRIB        0x00000004      /* Metadata changed */
+#define IN_CLOSE_WRITE   0x00000008      /* Writtable file was closed */
+#define IN_CLOSE_NOWRITE 0x00000010      /* Unwrittable file closed */
+#define IN_OPEN          0x00000020      /* File was opened */
+#define IN_MOVED_FROM    0x00000040      /* File was moved from X */
+#define IN_MOVED_TO      0x00000080      /* File was moved to Y */
+#define IN_CREATE        0x00000100      /* Subfile was created */
+#define IN_DELETE        0x00000200      /* Subfile was deleted */
+#define IN_DELETE_SELF   0x00000400      /* Self was deleted */
+#define IN_MOVE_SELF     0x00000800      /* Self was moved */
+
+#define IN_UNMOUNT       0x00002000      /* Backing fs was unmounted */
+#define IN_Q_OVERFLOW    0x00004000      /* Event queued overflowed */
+#define IN_IGNORED       0x00008000      /* File was ignored */
+
+#define IN_ONLYDIR       0x01000000      /* Only watch the path if it is a directory.  */
+#define IN_DONT_FOLLOW   0x02000000      /* Do not follow a sym link.  */
+#define IN_EXCL_UNLINK   0x04000000      /* Exclude events on unlinked objects.  */
+#define IN_MASK_CREATE   0x10000000      /* Only create watches.  */
+
+#define IN_MASK_ADD      0x20000000      /* Add to the mask of an already existing watch */
+#define IN_ISDIR         0x40000000      /* Event occurred against dir */
+#define IN_ONESHOT       0x80000000      /* Only send event once */
+
+#define IN_CLOSE        (IN_CLOSE_WRITE | IN_CLOSE_NOWRITE)  /* Close */
+#define IN_MOVE         (IN_MOVED_FROM | IN_MOVED_TO)        /* Moves */
+
+#define IN_ALL_EVENTS   (IN_ACCESS | IN_MODIFY | IN_ATTRIB | IN_CLOSE_WRITE | \
+                         IN_CLOSE_NOWRITE | IN_OPEN | IN_MOVED_FROM | IN_MOVED_TO | \
+                         IN_CREATE | IN_DELETE | IN_DELETE_SELF | IN_MOVE_SELF)
+
+#define IN_CLOEXEC       O_CLOEXEC   /* Set close_on_exec for the inotify file descriptor */
+#define IN_NONBLOCK      O_NONBLOCK  /* Set O_NONBLOCK for the inotify file descriptor */
+
+/****************************************************************************
+ * Type Definitions
+ ****************************************************************************/
+
+struct inotify_event
+{
+  int      wd;              /* Watch descriptor */
+  uint32_t mask;            /* Mask describing event */
+  uint32_t cookie;          /* Unique cookie associating related events (for rename(2)) */
+  uint32_t len;             /* Size of name field */
+  char     name[0];         /* Stub for possible name */
+};
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: inotify_init
+ *
+ * Description:
+ *  Initializes a new inotify instance and returns a file descriptor
+ *  associated with a new inotify event queue.
+ *
+ * Returned Value:
+ *  On success, these system calls return a new file descriptor.
+ *  On error, -1 is returned and errno is set appropriately.
+ *
+ ****************************************************************************/
+
+int inotify_init(void);
+
+/****************************************************************************
+ * Name: inotify_init1
+ *
+ * Description:
+ *  Initializes a new inotify instance and returns a file descriptor
+ *  associated with a new inotify event queue.
+ *
+ * Input Parameters:
+ *  flags - The following values are recognized in flags:
+ *    IN_NONBLOCK - Set the O_NONBLOCK file status flag on the new open file
+ *      description. Using this flag saves extra calls to fcntl(2) to achieve
+ *      the same result.
+ *    IN_CLOEXEC - Set the close-on-exec (FD_CLOEXEC) flag on the new file
+ *      descriptor. See the description of the O_CLOEXEC flag in open(2) for
+ *      reasons why this may be useful.
+ *
+ * Returned Value:
+ *  On success, these system calls return a new file descriptor.
+ *  On error, -1 is returned and errno is set appropriately.
+ *
+ ****************************************************************************/
+
+int inotify_init1(int flags);
+
+/****************************************************************************
+ * Name: inotify_add_watch
+ *
+ * Description:
+ *  Adds a new watch, or modifies an existing watch, for the file whose
+ *  location is specified in pathname; the caller must have read permission
+ *  for this file.  The fd argument is a file descriptor referring to the
+ *  inotify instance whose watch list is to be modified.  The events to be
+ *  monitored for pathname are specified in the mask bit-mask argument.
+ *
+ * Input Parameters:
+ *  fd - The file descriptor associated with an instance of inotify.
+ *  pathname - The path to the file to be monitored.
+ *  mask - The bit mask of events to be monitored.
+ *
+ * Returned Value:
+ *  On success, inotify_add_watch() returns a nonnegative watch descriptor.
+ *  On error, -1 is returned and errno is set appropriately.
+ *
+ ****************************************************************************/
+
+int inotify_add_watch(int fd, FAR const char *pathname, uint32_t mask);
+
+/****************************************************************************
+ * Name: inotify_rm_watch
+ *
+ * Description:
+ *  Removes the watch associated with the watch descriptor wd from the
+ *  inotify instance associated with the file descriptor fd.
+ *
+ * Input Parameters:
+ *  fd - The file descriptor associated with an instance of inotify.
+ *  wd - The watch descriptor to be removed.
+ *
+ * Returned Value:
+ *  On success, inotify_rm_watch() returns zero.  On error, -1 is returned
+ *  and errno is set appropriately.
+ *
+ ****************************************************************************/
+
+int inotify_rm_watch(int fd, int wd);
+
+#endif

include/sys/syscall_lookup.h

@@ -286,6 +286,15 @@ SYSCALL_LOOKUP(munmap,                     2)
   SYSCALL_LOOKUP(shm_unlink,               1)
 #endif
 
+/* The following are defined if the file system notify is enabled */
+
+#ifdef CONFIG_FS_NOTIFY
+  SYSCALL_LOOKUP(inotify_add_watch,        3)
+  SYSCALL_LOOKUP(inotify_init,             0)
+  SYSCALL_LOOKUP(inotify_init1,            1)
+  SYSCALL_LOOKUP(inotify_rm_watch,         2)
+#endif
+
 /* The following are defined if pthreads are enabled */
 
 #ifndef CONFIG_DISABLE_PTHREAD

syscall/syscall.csv

@@ -50,6 +50,10 @@
 "gettid","unistd.h","","pid_t"
 "gettimeofday","sys/time.h","","int","FAR struct timeval *","FAR struct timezone *"
 "getuid","unistd.h","defined(CONFIG_SCHED_USER_IDENTITY)","uid_t"
+"inotify_add_watch","sys/inotify.h","defined(CONFIG_FS_NOTIFY)","int","int","FAR const char *","uint32_t"
+"inotify_init","sys/inotify.h","defined(CONFIG_FS_NOTIFY)","int"
+"inotify_init1","sys/inotify.h","defined(CONFIG_FS_NOTIFY)","int","int"
+"inotify_rm_watch","sys/inotify.h","defined(CONFIG_FS_NOTIFY)","int","int","int"
 "insmod","nuttx/module.h","defined(CONFIG_MODULE)","FAR void *","FAR const char *","FAR const char *"
 "ioctl","sys/ioctl.h","","int","int","int","...","unsigned long"
 "kill","signal.h","","int","pid_t","int"