X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=osl.c;h=6e3eeca65db2a07d308f0fd2a30995867b29dbc9;hb=bd4ab2d82dec95a4deb2455c0e3394db3e0d3bc5;hp=ab3b8de4683df09c306bcd968ae868f2d978cc8d;hpb=2c679eeb8bbc93220f85403eca6e9380dc624a6a;p=paraslash.git

diff --git a/osl.c b/osl.c
index ab3b8de4..6e3eeca6 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.
@@ -1085,7 +1085,7 @@ 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,
@@ -1667,7 +1667,7 @@ 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 +1697,12 @@ 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 +1714,12 @@ 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 +1739,9 @@ 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.
  *
@@ -1829,7 +1835,7 @@ 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