seq_file: Rename seq_overflow() to seq_has_overflowed() and make public

The return values of seq_printf/puts/putc are frequently misused.

Start down a path to remove all the return value uses of these
functions.

Move the seq_overflow() to a global inlined function called
seq_has_overflowed() that can be used by the users of seq_file() calls.

Update the documentation to not show return types for seq_printf
et al.  Add a description of seq_has_overflowed().

Link: http://lkml.kernel.org/p/848ac7e3d1c31cddf638a8526fa3c59fa6fdeb8a.1412031505.git.joe@perches.com

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Joe Perches <joe@perches.com>
[ Reworked the original patch from Joe ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h
index 52e0097f61f0..cf6a9daaaf6d 100644
--- a/include/linux/seq_file.h
+++ b/include/linux/seq_file.h
@@ -43,6 +43,21 @@ struct seq_operations {
 #define SEQ_SKIP 1
 
 /**
+ * seq_has_overflowed - check if the buffer has overflowed
+ * @m: the seq_file handle
+ *
+ * seq_files have a buffer which may overflow. When this happens a larger
+ * buffer is reallocated and all the data will be printed again.
+ * The overflow state is true when m->count == m->size.
+ *
+ * Returns true if the buffer received more than it can hold.
+ */
+static inline bool seq_has_overflowed(struct seq_file *m)
+{
+	return m->count == m->size;
+}
+
+/**
  * seq_get_buf - get buffer to write arbitrary data to
  * @m: the seq_file handle
  * @bufp: the beginning of the buffer is stored here