Add dirsort module

1 files changed, 194 insertions, 0 deletions

diff --git a/source3/modules/vfs_dirsort.c b/source3/modules/vfs_dirsort.c
new file mode 100644
index 0000000000..f9a31c8976
--- /dev/null
+++ b/source3/modules/vfs_dirsort.c
@@ -0,0 +1,194 @@
+/*
+ * VFS module to provide a sorted directory list.
+ *
+ * Copyright (C) Andy Kelk (andy@mopoke.co.uk), 2009
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "includes.h"
+
+static int compare_dirent (const void *a, const void *b) {
+	const SMB_STRUCT_DIRENT *da = (const SMB_STRUCT_DIRENT *) a;
+	const SMB_STRUCT_DIRENT *db = (const SMB_STRUCT_DIRENT *) b;
+	return strcmp(da->d_name, db->d_name);
+}
+
+struct dirsort_privates {
+	long pos;
+	SMB_STRUCT_DIRENT *directory_list;
+	long number_of_entries;
+	time_t mtime;
+	SMB_STRUCT_DIR *source_directory;
+	int fd;
+};
+
+static void free_dirsort_privates(void **datap) {
+	struct dirsort_privates *data = (struct dirsort_privates *) *datap;
+	SAFE_FREE(data->directory_list);
+	SAFE_FREE(data);
+	*datap = NULL;
+
+	return;
+}
+
+static void open_and_sort_dir (vfs_handle_struct *handle)
+{
+	SMB_STRUCT_DIRENT *dp;
+	struct stat dir_stat;
+	long current_pos;
+	struct dirsort_privates *data = NULL;
+
+	SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates, return);
+
+	data->number_of_entries = 0;
+
+	if (fstat(data->fd, &dir_stat) == 0) {
+		data->mtime = dir_stat.st_mtime;
+	}
+
+	while (SMB_VFS_NEXT_READDIR(handle, data->source_directory, NULL)
+	       != NULL) {
+		data->number_of_entries++;
+	}
+
+	/* Open the underlying directory and count the number of entries
+	   Skip back to the beginning as we'll read it again */
+	SMB_VFS_NEXT_REWINDDIR(handle, data->source_directory);
+
+	/* Set up an array and read the directory entries into it */
+	SAFE_FREE(data->directory_list); /* destroy previous cache if needed */
+	data->directory_list = (SMB_STRUCT_DIRENT *)SMB_MALLOC(
+		data->number_of_entries * sizeof(SMB_STRUCT_DIRENT));
+	current_pos = data->pos;
+	data->pos = 0;
+	while ((dp = SMB_VFS_NEXT_READDIR(handle, data->source_directory,
+					  NULL)) != NULL) {
+		data->directory_list[data->pos++] = *dp;
+	}
+
+	/* Sort the directory entries by name */
+	data->pos = current_pos;
+	qsort(data->directory_list, data->number_of_entries,
+	      sizeof(SMB_STRUCT_DIRENT), compare_dirent);
+}
+
+static SMB_STRUCT_DIR *dirsort_opendir(vfs_handle_struct *handle,
+				       const char *fname, const char *mask,
+				       uint32 attr)
+{
+	struct dirsort_privates *data = NULL;
+
+	/* set up our private data about this directory */
+	data = (struct dirsort_privates *)SMB_MALLOC(
+		sizeof(struct dirsort_privates));
+
+	data->directory_list = NULL;
+	data->pos = 0;
+
+	/* Open the underlying directory and count the number of entries */
+	data->source_directory = SMB_VFS_NEXT_OPENDIR(handle, fname, mask,
+						      attr);
+
+	data->fd = dirfd(data->source_directory);
+
+	SMB_VFS_HANDLE_SET_DATA(handle, data, free_dirsort_privates,
+				struct dirsort_privates, return NULL);
+
+	open_and_sort_dir(handle);
+
+	return data->source_directory;
+}
+
+static SMB_STRUCT_DIRENT *dirsort_readdir(vfs_handle_struct *handle,
+					  SMB_STRUCT_DIR *dirp)
+{
+	struct dirsort_privates *data = NULL;
+	time_t current_mtime;
+	struct stat dir_stat;
+
+	SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates,
+				return NULL);
+
+	if (fstat(data->fd, &dir_stat) == -1) {
+		return NULL;
+	}
+
+	current_mtime = dir_stat.st_mtime;
+
+	/* throw away cache and re-read the directory if we've changed */
+	if (current_mtime > data->mtime) {
+		open_and_sort_dir(handle);
+	}
+
+	if (data->pos >= data->number_of_entries) {
+		return NULL;
+	}
+
+	return &data->directory_list[data->pos++];
+}
+
+static void dirsort_seekdir(vfs_handle_struct *handle, SMB_STRUCT_DIR *dirp,
+			    long offset)
+{
+	struct dirsort_privates *data = NULL;
+	SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates, return);
+
+	data->pos = offset;
+}
+
+static long dirsort_telldir(vfs_handle_struct *handle, SMB_STRUCT_DIR *dirp)
+{
+	struct dirsort_privates *data = NULL;
+	SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates,
+				return -1);
+
+	return data->pos;
+}
+
+static void dirsort_rewinddir(vfs_handle_struct *handle, SMB_STRUCT_DIR *dirp)
+{
+	struct dirsort_privates *data = NULL;
+	SMB_VFS_HANDLE_GET_DATA(handle, data, struct dirsort_privates, return);
+
+	data->pos = 0;
+}
+
+/* VFS operations structure */
+
+static vfs_op_tuple dirsort_op_tuples[] = {
+
+    /* Directory operations */
+
+    {SMB_VFS_OP(dirsort_opendir),	     SMB_VFS_OP_OPENDIR,
+     SMB_VFS_LAYER_TRANSPARENT},
+    {SMB_VFS_OP(dirsort_readdir),	     SMB_VFS_OP_READDIR,
+     SMB_VFS_LAYER_TRANSPARENT},
+    {SMB_VFS_OP(dirsort_seekdir),	     SMB_VFS_OP_SEEKDIR,
+     SMB_VFS_LAYER_TRANSPARENT},
+    {SMB_VFS_OP(dirsort_telldir),	     SMB_VFS_OP_TELLDIR,
+     SMB_VFS_LAYER_TRANSPARENT},
+    {SMB_VFS_OP(dirsort_rewinddir),	     SMB_VFS_OP_REWINDDIR,
+     SMB_VFS_LAYER_TRANSPARENT},
+
+    {NULL,				     SMB_VFS_OP_NOOP,
+     SMB_VFS_LAYER_NOOP}
+};
+
+NTSTATUS vfs_dirsort_init(void)
+{
+	return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "dirsort",
+				dirsort_op_tuples);
+}