fs: fat: factor out dentry link create/delete

The create_link() code was previously duplicated in two existing functions.
The two functions will be used in a future commit to achieve renaming.

Signed-off-by: Gabriel Dalimonte <gabriel.dalimonte@gmail.com>

diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
index ea877ee..86366d0 100644 (file)
--- a/fs/fat/fat_write.c
+++ b/fs/fat/fat_write.c
@@ -1215,6 +1215,43 @@ static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
        memcpy(&dentptr->nameext, shortname, SHORT_NAME_SIZE);
 }
 
+/**
+ * create_link() - inserts a directory entry for a file or directory
+ *
+ * @itr:       directory iterator
+ * @basename:  file name
+ * @clust:     cluster number the new directory entry should point to. Use 0
+ * if no cluster is assigned yet
+ * @size:      file size
+ * @attr:      file attributes
+ * Return:     0 for success
+ */
+static int create_link(fat_itr *itr, char *basename, __u32 clust, __u32 size,
+                      __u8 attr)
+{
+       char shortname[SHORT_NAME_SIZE];
+       int ndent;
+       int ret;
+
+       /* Check if long name is needed */
+       ndent = set_name(itr, basename, shortname);
+       if (ndent < 0)
+               return ndent;
+       ret = fat_find_empty_dentries(itr, ndent);
+       if (ret)
+               return ret;
+       if (ndent > 1) {
+               /* Set long name entries */
+               ret = fill_dir_slot(itr, basename, shortname);
+               if (ret)
+                       return ret;
+       }
+
+       fill_dentry(itr->fsdata, itr->dent, shortname, clust, size, attr);
+
+       return 0;
+}
+
 /**
  * find_directory_entry() - find a directory entry by filename
  *
@@ -1420,35 +1457,15 @@ int file_fat_write_at(const char *filename, loff_t pos, void *buffer,
                /* Update change date */
                dentry_set_time(retdent);
        } else {
-               /* Create a new file */
-               char shortname[SHORT_NAME_SIZE];
-               int ndent;
-
                if (pos) {
                        /* No hole allowed */
                        ret = -EINVAL;
                        goto exit;
                }
 
-               /* Check if long name is needed */
-               ndent = set_name(itr, basename, shortname);
-               if (ndent < 0) {
-                       ret = ndent;
-                       goto exit;
-               }
-               ret = fat_find_empty_dentries(itr, ndent);
+               ret = create_link(itr, basename, 0, size, ATTR_ARCH);
                if (ret)
                        goto exit;
-               if (ndent > 1) {
-                       /* Set long name entries */
-                       ret = fill_dir_slot(itr, basename, shortname);
-                       if (ret)
-                               goto exit;
-               }
-
-               /* Set short name entry */
-               fill_dentry(itr->fsdata, itr->dent, shortname, 0, size,
-                           ATTR_ARCH);
 
                retdent = itr->dent;
        }
@@ -1564,6 +1581,31 @@ static int delete_long_name(fat_itr *itr)
        return 0;
 }
 
+/**
+ * delete_dentry_link() - deletes a directory entry, but not the cluster chain
+ * it points to
+ *
+ * @itr:       the first directory entry (if a longname) to remove
+ * Return:     0 for success
+ */
+static int delete_dentry_link(fat_itr *itr)
+{
+       itr->dent = itr->dent_start;
+       itr->remaining = itr->dent_rem;
+       /* Delete long name */
+       if ((itr->dent->attr & ATTR_VFAT) == ATTR_VFAT &&
+           (itr->dent->nameext.name[0] & LAST_LONG_ENTRY_MASK)) {
+               int ret;
+
+               ret = delete_long_name(itr);
+               if (ret)
+                       return ret;
+       }
+       /* Delete short name */
+       delete_single_dentry(itr);
+       return flush_dir(itr);
+}
+
 /**
  * delete_dentry_long() - remove directory entry
  *
@@ -1589,21 +1631,7 @@ static int delete_dentry_long(fat_itr *itr)
                if (ret)
                        return ret;
        }
-       itr->dent = itr->dent_start;
-       itr->remaining = itr->dent_rem;
-       dent = itr->dent_start;
-       /* Delete long name */
-       if ((dent->attr & ATTR_VFAT) == ATTR_VFAT &&
-           (dent->nameext.name[0] & LAST_LONG_ENTRY_MASK)) {
-               int ret;
-
-               ret = delete_long_name(itr);
-               if (ret)
-                       return ret;
-       }
-       /* Delete short name */
-       delete_single_dentry(itr);
-       return flush_dir(itr);
+       return delete_dentry_link(itr);
 }
 
 int fat_unlink(const char *filename)
@@ -1725,9 +1753,6 @@ int fat_mkdir(const char *dirname)
                ret = -EEXIST;
                goto exit;
        } else {
-               char shortname[SHORT_NAME_SIZE];
-               int ndent;
-
                if (itr->is_root) {
                        /* root dir cannot have "." or ".." */
                        if (!strcmp(l_dirname, ".") ||
@@ -1737,25 +1762,9 @@ int fat_mkdir(const char *dirname)
                        }
                }
 
-               /* Check if long name is needed */
-               ndent = set_name(itr, basename, shortname);
-               if (ndent < 0) {
-                       ret = ndent;
-                       goto exit;
-               }
-               ret = fat_find_empty_dentries(itr, ndent);
+               ret = create_link(itr, basename, 0, 0, ATTR_DIR | ATTR_ARCH);
                if (ret)
                        goto exit;
-               if (ndent > 1) {
-                       /* Set long name entries */
-                       ret = fill_dir_slot(itr, basename, shortname);
-                       if (ret)
-                               goto exit;
-               }
-
-               /* Set attribute as archive for regular file */
-               fill_dentry(itr->fsdata, itr->dent, shortname, 0, 0,
-                           ATTR_DIR | ATTR_ARCH);
 
                retdent = itr->dent;
        }