Add FAT rmdir and unlink

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@247 42af7a65-404d-4744-a932-0658087f49c3

3 files changed, 226 insertions, 38 deletions

diff --git a/nuttx/fs/fs_fat32.c b/nuttx/fs/fs_fat32.c
index 81992e72d..d0561f380 100644
--- a/nuttx/fs/fs_fat32.c
+++ b/nuttx/fs/fs_fat32.c
@@ -73,7 +73,7 @@
  * Private Function Prototypes
  ****************************************************************************/
 
-static int     fat_open(FAR struct file *filp, const char *rel_path,
+static int     fat_open(FAR struct file *filp, const char *relpath,
                         int oflags, mode_t mode);
 static int     fat_close(FAR struct file *filp);
 static ssize_t fat_read(FAR struct file *filp, char *buffer, size_t buflen);
@@ -86,10 +86,10 @@ static int     fat_sync(FAR struct file *filp);
 static int     fat_bind(FAR struct inode *blkdriver, const void *data,
                         void **handle);
 static int     fat_unbind(void *handle);
-static int     fat_unlink(struct inode *mountpt, const char *rel_path);
-static int     fat_mkdir(struct inode *mountpt, const char *rel_path,
+static int     fat_unlink(struct inode *mountpt, const char *relpath);
+static int     fat_mkdir(struct inode *mountpt, const char *relpath,
                          mode_t mode);
-static int     fat_rmdir(struct inode *mountpt, const char *rel_path);
+static int     fat_rmdir(struct inode *mountpt, const char *relpath);
 static int     fat_rename(struct inode *mountpt, const char *old_relpath,
                           const char *new_relpath);
 
@@ -120,6 +120,7 @@ const struct mountpt_operations fat_operations =
   fat_unbind,
   fat_unlink,
   fat_mkdir,
+  fat_rmdir,
   fat_rename
 };
 
@@ -131,7 +132,7 @@ const struct mountpt_operations fat_operations =
  * Name: fat_open
  ****************************************************************************/
 
-static int fat_open(FAR struct file *filp, const char *rel_path,
+static int fat_open(FAR struct file *filp, const char *relpath,
                     int oflags, mode_t mode)
 {
   struct fat_dirinfo_s  dirinfo;
@@ -165,13 +166,12 @@ static int fat_open(FAR struct file *filp, const char *rel_path,
   /* Initialize the directory info structure */
 
   memset(&dirinfo, 0, sizeof(struct fat_dirinfo_s));
-  dirinfo.fs = fs;
 
   /* Locate the directory entry for this path */
 
-  ret = fat_finddirentry(&dirinfo, rel_path);
+  ret = fat_finddirentry(fs, &dirinfo, relpath);
 
-  /* Three possibililities: (1) a node exists for the rel_path and
+  /* Three possibililities: (1) a node exists for the relpath and
    * dirinfo describes the directory entry of the entity, (2) the
    * node does not exist, or (3) some error occurred.
    */
@@ -206,7 +206,7 @@ static int fat_open(FAR struct file *filp, const char *rel_path,
       /* Check if the caller has sufficient privileges to open the file */
 
       readonly = ((DIR_GETATTRIBUTES(dirinfo.fd_entry) & FATATTR_READONLY) != 0);
-      if (((oflags && O_WRONLY) != 0) && readonly)
+      if (((oflags & O_WRONLY) != 0) && readonly)
         {
           ret = -EACCES;
           goto errout_with_semaphore;
@@ -236,7 +236,7 @@ static int fat_open(FAR struct file *filp, const char *rel_path,
     {
       /* The file does not exist.  Were we asked to create it? */
 
-      if ((oflags && O_CREAT) == 0)
+      if ((oflags & O_CREAT) == 0)
         {
           /* No.. then we fail with -ENOENT */
           ret = -ENOENT;
@@ -303,7 +303,7 @@ static int fat_open(FAR struct file *filp, const char *rel_path,
 
   /* In write/append mode, we need to set the file pointer to the end of the file */
 
-  if ((oflags && (O_APPEND|O_WRONLY)) == (O_APPEND|O_WRONLY))
+  if ((oflags & (O_APPEND|O_WRONLY)) == (O_APPEND|O_WRONLY))
     {
         ff->ff_position   = ff->ff_size;
     }
@@ -1320,7 +1320,7 @@ static int fat_unbind(void *handle)
  *
  ****************************************************************************/
 
-static int fat_unlink(struct inode *mountpt, const char *rel_path)
+static int fat_unlink(struct inode *mountpt, const char *relpath)
 {
   struct fat_mountpt_s *fs;
   int                   ret;
@@ -1337,15 +1337,20 @@ static int fat_unlink(struct inode *mountpt, const char *rel_path)
 
   fat_semtake(fs);
   ret = fat_checkmount(fs);
-  if (ret != OK)
+  if (ret == OK)
     {
-      goto errout_with_semaphore;
-    }
+      /* If the file is open, the correct behavior is to remove the file
+       * name, but to keep the file cluster chain in place until the last
+       * open reference to the file is closed.
+       */
 
-#warning "fat_unlink is not implemented"
-  ret = -ENOSYS;
+#warning "Need to defer deleting cluster chain if the file is open"
+
+      /* Remove the file */
+
+      ret = fat_remove(fs, relpath, FALSE);
+    }
 
- errout_with_semaphore:
   fat_semgive(fs);
   return ret;
 }
@@ -1357,7 +1362,7 @@ static int fat_unlink(struct inode *mountpt, const char *rel_path)
  *
  ****************************************************************************/
 
-static int fat_mkdir(struct inode *mountpt, const char *rel_path, mode_t mode)
+static int fat_mkdir(struct inode *mountpt, const char *relpath, mode_t mode)
 {
   struct fat_mountpt_s *fs;
   int                   ret;
@@ -1394,7 +1399,7 @@ static int fat_mkdir(struct inode *mountpt, const char *rel_path, mode_t mode)
  *
  ****************************************************************************/
 
-int fat_rmdir(struct inode *mountpt, const char *rel_path)
+int fat_rmdir(struct inode *mountpt, const char *relpath)
 {
   struct fat_mountpt_s *fs;
   int                   ret;
@@ -1411,15 +1416,20 @@ int fat_rmdir(struct inode *mountpt, const char *rel_path)
 
   fat_semtake(fs);
   ret = fat_checkmount(fs);
-  if (ret != OK)
+  if (ret == OK)
     {
-      goto errout_with_semaphore;
-    }
+      /* If the directory is open, the correct behavior is to remove the directory
+       * name, but to keep the directory cluster chain in place until the last
+       * open reference to the directory is closed.
+       */
 
-#warning "fat_rmdir is not implemented"
-  ret = -ENOSYS;
+#warning "Need to defer deleting cluster chain if the directory is open"
+
+      /* Remove the directory */
+
+      ret = fat_remove(fs, relpath, TRUE);
+    }
 
- errout_with_semaphore:
   fat_semgive(fs);
   return ret;
 }
diff --git a/nuttx/fs/fs_fat32.h b/nuttx/fs/fs_fat32.h
index 9e10cd7d8..e8edd14c7 100644
--- a/nuttx/fs/fs_fat32.h
+++ b/nuttx/fs/fs_fat32.h
@@ -488,7 +488,6 @@ struct fat_file_s
 
 struct fat_dirinfo_s
 {
-  struct fat_mountpt_s *fs;        /* Pointer to the parent mountpoint */
   ubyte    fd_name[8+3];           /* Filename -- directory format*/
 #ifdef CONFIG_FAT_LCNAMES
   ubyte    fd_ntflags;             /* NTRes lower case flags */
@@ -557,15 +556,17 @@ EXTERN sint32 fat_extendchain(struct fat_mountpt_s *fs, uint32 cluster);
 
 /* Help for traverseing directory trees */
 
-EXTERN int    fat_nextdirentry(struct fat_dirinfo_s *dirinfo);
-EXTERN int    fat_finddirentry(struct fat_dirinfo_s *dirinfo, const char *path);
+EXTERN int    fat_nextdirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo);
+EXTERN int    fat_finddirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo,
+                               const char *path);
 
-/* File creation helpers */
+/* File creation and removal helpers */
 
 EXTERN int    fat_dirtruncate(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo);
 EXTERN int    fat_dircreate(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo);
+EXTERN int    fat_remove(struct fat_mountpt_s *fs, const char *relpath, boolean directory);
 
-/* Mountpoint and fFile buffer cache (for partial sector accesses) */
+/* Mountpoint and file buffer cache (for partial sector accesses) */
 
 EXTERN int    fat_fscacheread(struct fat_mountpt_s *fs, size_t sector);
 EXTERN int    fat_ffcacheflush(struct fat_mountpt_s *fs, struct fat_file_s *ff);
diff --git a/nuttx/fs/fs_fat32util.c b/nuttx/fs/fs_fat32util.c
index 826d13bec..eb7981a56 100644
--- a/nuttx/fs/fs_fat32util.c
+++ b/nuttx/fs/fs_fat32util.c
@@ -471,7 +471,7 @@ static int fat_allocatedirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *
           return OK;
         }
 
-      ret = fat_nextdirentry(dirinfo);
+      ret = fat_nextdirentry(fs, dirinfo);
       if (ret < 0)
         {
           return ret;
@@ -1583,9 +1583,8 @@ sint32 fat_extendchain(struct fat_mountpt_s *fs, uint32 cluster)
  *
  ****************************************************************************/
 
-int fat_nextdirentry(struct fat_dirinfo_s *dirinfo)
+int fat_nextdirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo)
 {
-  struct fat_mountpt_s *fs = dirinfo->fs;
   unsigned int cluster;
   unsigned int ndx;
 
@@ -1674,9 +1673,9 @@ int fat_nextdirentry(struct fat_dirinfo_s *dirinfo)
  *
  ****************************************************************************/
 
-int fat_finddirentry(struct fat_dirinfo_s *dirinfo, const char *path)
+int fat_finddirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo,
+                     const char *path)
 {
-  struct fat_mountpt_s *fs = dirinfo->fs;
   size_t cluster;
   ubyte *direntry = NULL;
   char terminator;
@@ -1778,7 +1777,7 @@ int fat_finddirentry(struct fat_dirinfo_s *dirinfo, const char *path)
 
           /* No... get the next directory index and try again */
 
-          if (fat_nextdirentry(dirinfo) != OK)
+          if (fat_nextdirentry(fs, dirinfo) != OK)
             {
               return -ENOENT;
             }
@@ -1936,6 +1935,184 @@ int fat_dircreate(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo)
 }
 
 /****************************************************************************
+ * Name: fat_remove
+ *
+ * Desciption: Remove a directory or file from the file system.  This
+ *   implements both rmdir() and unlink().
+ *
+ ****************************************************************************/
+
+int fat_remove(struct fat_mountpt_s *fs, const char *relpath, boolean directory)
+{
+  struct fat_dirinfo_s dirinfo;
+  uint32  dircluster;
+  size_t  dirsector;
+  int     ret;
+
+  /* Find the directory entry referring to the entry to be deleted */
+
+  ret = fat_finddirentry(fs, &dirinfo, relpath);
+  if (ret != OK)
+    {
+      /* No such path */
+
+      return -ENOENT;
+    }
+
+  /* Check if this is a FAT12/16 root directory */
+
+  if (dirinfo.fd_entry == NULL)
+    {
+      /* The root directory cannot be removed */
+
+      return -EPERM;
+    }
+
+  /* The object has to have write access to be deleted */
+
+  if ((DIR_GETATTRIBUTES(dirinfo.fd_entry) & FATATTR_READONLY) != 0)
+    {
+      /* It is a read-only entry */
+
+      return -EACCES;
+    }
+
+  /* Get the directory sector and cluster containing the
+   * entry to be deleted
+   */
+
+  dirsector  = fs->fs_currentsector;
+  dircluster =
+      ((uint32)DIR_GETFSTCLUSTHI(dirinfo.fd_entry) << 16) |
+      DIR_GETFSTCLUSTLO(dirinfo.fd_entry);
+
+  /* Is this entry a directory? */
+
+  if (DIR_GETATTRIBUTES(dirinfo.fd_entry) & FATATTR_DIRECTORY)
+    {
+      /* It is a sub-directory. Check if we are be asked to remove
+       * a directory or a file.
+       */
+
+      if (!directory)
+        {
+          /* We are asked to delete a file */
+
+          return -EISDIR;
+        }
+
+      /* We are asked to delete a directory. Check if this
+       * sub-directory is empty
+       */
+
+      dirinfo.fd_currcluster = dircluster;
+      dirinfo.fd_currsector  = fat_cluster2sector(fs, dircluster);
+      dirinfo.fd_index       = 2;
+
+      /* Loop until either (1) an entry is found in the directory
+       * (error), (2) the directory is found to be empty, or (3) some
+       * error occurs.
+       */
+
+      for (;;)
+        {
+          unsigned int subdirindex;
+          ubyte       *subdirentry;
+
+          /* Make sure that the sector containing the of the
+           * subdirectory sector is in the cache
+           */
+
+          ret = fat_fscacheread(fs, dirinfo.fd_currsector);
+          if (ret < 0)
+            {
+              return ret;
+            }
+
+          /* Get a reference to the next entry in the directory */
+
+          subdirindex = (dirinfo.fd_index & DIRSEC_NDXMASK(fs)) * 32;
+          subdirentry = &fs->fs_buffer[subdirindex];
+
+          /* Is this the last entry in the direcory? */
+
+          if (subdirentry[DIR_NAME] == DIR0_ALLEMPTY)
+            {
+              /* Yes then the directory is empty.  Break out of the
+               * loop and delete the directory.
+               */
+
+              break;
+            }
+
+          /* Check if the next entry refers to a file or directory */
+
+          if (subdirentry[DIR_NAME] != DIR0_EMPTY &&
+              !(DIR_GETATTRIBUTES(subdirentry) & FATATTR_VOLUMEID))
+            {
+              /* The directory is not empty */
+
+              return -ENOTEMPTY;
+            }
+
+          /* Get the next directgory entry */
+
+          ret = fat_nextdirentry(fs, &dirinfo);
+          if (ret < 0)
+            {
+              return ret;
+            }
+        }
+    }
+  else
+    {
+      /* It is a file. Check if we are be asked to remove a directory
+       * or a file.
+       */
+
+      if (directory)
+        {
+          /* We are asked to remove a directory */
+
+          return -ENOTDIR;
+        }
+    }
+
+  /* Make sure that the directory containing the entry to be deleted is
+   * in the cache.
+   */
+
+  ret = fat_fscacheread(fs, dirsector);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  /* Mark the directory entry 'deleted' */
+
+  dirinfo.fd_entry[DIR_NAME] = DIR0_EMPTY;
+  fs->fs_dirty = TRUE;
+
+  /* And remove the cluster chain making up the subdirectory */
+
+  ret = fat_removechain(fs, dircluster);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  /* Update the FSINFO sector (FAT32) */
+
+  ret = fat_updatefsinfo(fs);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  return OK;
+}
+
+/****************************************************************************
  * Name: fat_fscacheread
  *
  * Desciption: Read the specified sector into the sector cache, flushing any
@@ -2092,7 +2269,7 @@ int fat_ffcacheinvalidate(struct fat_mountpt_s *fs, struct fat_file_s *ff)
  * Name: fat_updatefsinfo
  *
  * Desciption: Flush evertyhing buffered for the mountpoint and update
- *  the FSINFO sector, if appropriate
+ *   the FSINFO sector, if appropriate
  *
  ****************************************************************************/