On Thu, 2013-12-12 at 10:27 +1100, Ryan Mallon wrote: > On 11/12/13 16:12, Joe Perches wrote: > > seq_printf and seq_puts returns are often misused. > > > > Instead of checking the seq_printf or seq_puts return, > > add a new seq_overflow function to test if a seq_file has > > overflowed the available buffer space. > > > > This will eventually allow seq_printf and seq_puts to be > > converted to have a void return instead of the int return > > that is often assumed to have a size_t value instead of an > > error/no-error value. > > > > Signed-off-by: Joe Perches <[email protected]> > > --- > > fs/seq_file.c | 15 ++++++++------- > > include/linux/seq_file.h | 2 ++ > > 2 files changed, 10 insertions(+), 7 deletions(-) > > > > diff --git a/fs/seq_file.c b/fs/seq_file.c > > index 1d641bb..aab0736 100644 > > --- a/fs/seq_file.c > > +++ b/fs/seq_file.c > > @@ -14,16 +14,17 @@ > > #include <asm/uaccess.h> > > #include <asm/page.h> > > > > - > > -/* > > - * seq_files have a buffer which can 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. > > +/** > > + * seq_overflow - test if a seq_file has overflowed the space available > > + * @m: the seq_file handle > > + * > > + * Returns -1 when an overflow has occurred, 0 otherwise. > > */ > > -static bool seq_overflow(struct seq_file *m) > > +int seq_overflow(struct seq_file *m) > > { > > - return m->count == m->size; > > + return m->count == m->size ? -1 : 0; > > } > > +EXPORT_SYMBOL(seq_overflow); > > What is the reasoning in making this return int instead of bool? Having > it return int encourages people to do: > > return seq_overflow(s); > > When used in seq_file functions will return -EPERM (-1) to user-space, > which is confusing. It should probably return bool and let the caller > sort out the correct error to return.
It was intended to make the return from seq_printf the same. Anyway, the patch series is out of date (see Al's comments). I'll update it later unless you or someone else does it first. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
