X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=osl.c;h=36da808af853aa58495382c2c6fd1afe3893b5e8;hb=cd38753609763dbc55e72a7df446837792628d6d;hp=ab3b8de4683df09c306bcd968ae868f2d978cc8d;hpb=2c679eeb8bbc93220f85403eca6e9380dc624a6a;p=paraslash.git

diff --git a/osl.c b/osl.c
index ab3b8de4..36da808a 100644
--- a/osl.c
+++ b/osl.c
@@ -17,7 +17,7 @@
 /**
  * A wrapper for lseek(2).
  *
- * \param fd The filedescriptor whose offset is to be to repositioned.
+ * \param fd The file descriptor whose offset is to be to repositioned.
  * \param offset A value-result parameter.
  * \param whence Usual repositioning directive.
  *
@@ -46,8 +46,8 @@ int para_lseek(int fd, off_t *offset, int whence)
  * \param buf The buffer to write.
  * \param size The length of \a buf in bytes.
  *
- * This function writes out the given bufffer and retries if an interrupt
- * occured during the write.
+ * This function writes out the given buffer and retries if an interrupt
+ * occurred during the write.
  *
  * \return On success, the number of bytes written is returned, otherwise, the
  * function returns \p -E_WRITE.
@@ -211,9 +211,10 @@ out:
  * \param func The function to call for each entry.
  * \param private_data Pointer to an arbitrary data structure.
  *
- * For each regular file  in \a dirname, the supplied function \a func is
+ * For each regular file under \a dirname, the supplied function \a func is
  * called.  The full path of the regular file and the \a private_data pointer
- * are passed to \a func.
+ * are passed to \a func. Directories for which the calling process has no
+ * permissions to change to are silently ignored.
  *
  * \return On success, 1 is returned. Otherwise, this function returns a
  * negative value which indicates the kind of the error.
@@ -226,7 +227,7 @@ int for_each_file_in_dir(const char *dirname,
 	int cwd_fd, ret2, ret = para_opendir(dirname, &dir, &cwd_fd);
 
 	if (ret < 0)
-		return ret;
+		return ret == -E_CHDIR_PERM? 1 : ret;
 	/* scan cwd recursively */
 	while ((entry = readdir(dir))) {
 		mode_t m;
@@ -365,7 +366,7 @@ static int init_column_descriptions(struct osl_table *t)
 	if (ret < 0)
 		goto err;
 	ret = -E_BAD_DB_DIR;
-	if (!t->desc->dir)
+	if (!t->desc->dir && (t->num_disk_storage_columns || t->num_mapped_columns))
 		goto err;
 	/* the size of the index header without column descriptions */
 	t->index_header_size = IDX_COLUMN_DESCRIPTIONS;
@@ -658,10 +659,7 @@ static int create_table_index(struct osl_table *t)
  *
  * \param desc Pointer to the table description.
  *
- * \return Positive on success, negative on errors. Possible errors include: \p
- * E_BAD_TABLE_DESC, \p E_BAD_DB_DIR, \p E_BAD_NAME, \p E_NO_COMPARE_FUNC, \p
- * E_NO_COLUMN_NAME, \p E_DUPLICATE_COL_NAME, \p E_MKDIR, any errors returned
- * by para_open().
+ * \return Standard.
  */
 int osl_create_table(const struct osl_table_description *desc)
 {
@@ -678,7 +676,7 @@ int osl_create_table(const struct osl_table_description *desc)
 			continue;
 		if (!table_dir) {
 			ret = para_mkdir(desc->dir, 0777);
-			if (ret < 0 && ret != -E_EXIST)
+			if (ret < 0 && !is_errno(-ret, EEXIST))
 				goto out;
 			table_dir = make_message("%s/%s", desc->dir,
 				desc->name);
@@ -1085,7 +1083,7 @@ void clear_rbtrees(struct osl_table *t)
  * \param flags Options for what should be cleaned up.
  *
  * If osl_open_table() succeeds, the resulting table pointer must later be
- * passed to this function in order to flush all changes to the filesystem and
+ * passed to this function in order to flush all changes to the file system and
  * to free the resources that were allocated by osl_open_table().
  *
  * \return Positive on success, negative on errors. Possible errors: \p E_BAD_TABLE,
@@ -1202,10 +1200,7 @@ int init_rbtrees(struct osl_table *t)
  * The table description given by \a desc should coincide with the
  * description used at creation time.
  *
- * \return Positive on success, negative on errors. Possible errors include:
- * errors returned by init_table_structure(), \p E_NOENT, \p E_STAT, \p \p
- * E_NOTDIR, \p E_BAD_TABLE_DESC, \p E_BAD_DB_DIR, \p E_NO_COMPARE_FUNC, \p
- * E_NO_COLUMN_NAME, errors returned by init_rbtrees().
+ * \return Standard.
  */
 int osl_open_table(const struct osl_table_description *table_desc,
 		struct osl_table **result)
@@ -1225,13 +1220,10 @@ int osl_open_table(const struct osl_table_description *table_desc,
 		ret = stat(dirname, &statbuf);
 		free(dirname);
 		if (ret < 0) {
-			if (errno == ENOENT)
-				ret = -E_NOENT;
-			else
-				ret = -E_STAT;
+			ret = -ERRNO_TO_PARA_ERROR(errno);
 			goto err;
 		}
-		ret = -E_NOTDIR;
+		ret = -ERRNO_TO_PARA_ERROR(ENOTDIR);
 		if (!S_ISDIR(statbuf.st_mode))
 			goto err;
 	}
@@ -1264,7 +1256,7 @@ static int create_disk_storage_object_dir(const struct osl_table *t,
 	dirname = disk_storage_dirname(t, col_num, ds_name);
 	ret = para_mkdir(dirname, 0777);
 	free(dirname);
-	if (ret < 0 && ret != -E_EXIST)
+	if (ret < 0 && !is_errno(-ret, EEXIST))
 		return ret;
 	return 1;
 }
@@ -1357,15 +1349,11 @@ static int delete_disk_storage_file(const struct osl_table *t, unsigned col_num,
 		const char *ds_name)
 {
 	char *dirname, *filename = disk_storage_path(t, col_num, ds_name);
-	int ret = unlink(filename);
+	int ret = unlink(filename), err = errno;
 
-	PARA_DEBUG_LOG("deleted %s\n", filename);
 	free(filename);
-	if (ret < 0) {
-		if (errno == ENOENT)
-			return -E_NOENT;
-		return -E_UNLINK;
-	}
+	if (ret < 0)
+		return -ERRNO_TO_PARA_ERROR(err);
 	if (!(t->desc->flags & OSL_LARGE_TABLE))
 		return 1;
 	dirname = disk_storage_dirname(t, col_num, ds_name);
@@ -1667,7 +1655,7 @@ static int check_rbtree_col(const struct osl_table *t, unsigned col_num,
  * Lookup \a obj in \a t and return the row containing \a obj. The column
  * specified by \a col_num must have an associated rbtree.
  *
- * \return Positive on success, negative on errors. If an error occured, \a
+ * \return Positive on success, negative on errors. If an error occurred, \a
  * result is set to \p NULL. Possible errors include: \p E_BAD_TABLE, \p
  * E_BAD_STORAGE_FLAGS, errors returned by get_mapped_object(), \p
  * E_RB_KEY_NOT_FOUND.
@@ -1697,9 +1685,12 @@ int osl_get_row(const struct osl_table *t, unsigned col_num,
 static int rbtree_loop(struct osl_column *col,  void *private_data,
 		osl_rbtree_loop_func *func)
 {
-	struct rb_node *n;
+	struct rb_node *n, *tmp;
 
-	for (n = rb_first(&col->rbtree); n; n = rb_next(n)) {
+	/* this for-loop is safe against removal of an entry */
+	for (n = rb_first(&col->rbtree), tmp = n? rb_next(n) : NULL;
+			n;
+			n = tmp, tmp = tmp? rb_next(tmp) : NULL) {
 		struct osl_row *r = get_row_pointer(n, col->rbtree_num);
 		int ret = func(r, private_data);
 		if (ret < 0)
@@ -1711,9 +1702,12 @@ static int rbtree_loop(struct osl_column *col,  void *private_data,
 static int rbtree_loop_reverse(struct osl_column *col,  void *private_data,
 		osl_rbtree_loop_func *func)
 {
-	struct rb_node *n;
+	struct rb_node *n, *tmp;
 
-	for (n = rb_last(&col->rbtree); n; n = rb_prev(n)) {
+	/* safe against removal of an entry */
+	for (n = rb_last(&col->rbtree), tmp = n? rb_prev(n) : NULL;
+			n;
+			n = tmp, tmp = tmp? rb_prev(tmp) : NULL) {
 		struct osl_row *r = get_row_pointer(n, col->rbtree_num);
 		int ret = func(r, private_data);
 		if (ret < 0)
@@ -1733,9 +1727,9 @@ static int rbtree_loop_reverse(struct osl_column *col,  void *private_data,
  * This function does an in-order walk of the rbtree associated with \a
  * col_num. It is an error if the \p OSL_RBTREE flag is not set for this
  * column. For each node in the rbtree, the given function \a func is called
- * with two \p void* pointers as arguments: The first argument points to the
+ * with two pointers as arguments: The first osl_row* argument points to the
  * row that contains the object corresponding to the rbtree node currently
- * traversed, and the \a private_data pointer is passed to \a func as the
+ * traversed, and the \a private_data pointer is passed verbatim to \a func as the
  * second argument. The loop terminates either if \a func returns a negative
  * value, or if all nodes of the tree have been visited.
  *
@@ -1829,16 +1823,14 @@ out:
  *
  * This function  gets rid of all references to the old object. This includes
  * removal of the rbtree node in case there is an rbtree associated with \a
- * col_num. It then inserts \a obj into the table and the rbtree if neccessary.
+ * col_num. It then inserts \a obj into the table and the rbtree if necessary.
  *
  * If the \p OSL_RBTREE flag is set for \a col_num, you \b MUST call this
  * function in order to change the contents of an object, even for volatile or
  * mapped columns of constant size (which may be updated directly if \p
  * OSL_RBTREE is not set).  Otherwise the rbtree might become corrupted.
  *
- * \return Positive on success, negative on errors. Possible errors include: \p
- * E_BAD_TABLE, \p E_RB_KEY_EXISTS, \p E_BAD_SIZE, \p E_NOENT, \p E_UNLINK,
- * errors returned by para_write_file(), \p E_MKDIR.
+ * \return Standard
  */
 int osl_update_object(struct osl_table *t, const struct osl_row *r,
 		unsigned col_num, struct osl_object *obj)
@@ -1870,7 +1862,7 @@ int osl_update_object(struct osl_table *t, const struct osl_row *r,
 		if (ret < 0)
 			return ret;
 		ret = delete_disk_storage_file(t, col_num, ds_name);
-		if (ret < 0 && ret != -E_NOENT) {
+		if (ret < 0 && !is_errno(-ret, ENOENT)) {
 			free(ds_name);
 			return ret;
 		}
@@ -2007,7 +1999,7 @@ int osl_get_num_rows(const struct osl_table *t, unsigned *num_rows)
  * \param rank Result pointer.
  *
  * The rank is, by definition, the position of the row in the linear order
- * determined by an inorder tree walk of the rbtree associated with column
+ * determined by an in-order tree walk of the rbtree associated with column
  * number \a col_num of \a table.
  *
  * \return Positive on success, negative on errors.