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    SubjectRe: 2.6.13-rc6-mm1
    On Sun, Aug 21, 2005 at 06:34:48PM -0400, Jon Smirl wrote:
    > This should fix it, but I'm not on a machine where I can test it. Can
    > you give it a try and let me know?
    >

    it works ok.
    But there is still at least one problem: if ops->store returns an error,
    then there will be a substraction and the write will loop (i could do it
    with a store wich returned EINVAL and a 22 length string).

    I don't know if you can put a '\0' at buffer->page[count] if
    count == PAGE_SIZE.

    Moreover, i think it is more correct to add only the leading
    whitespace from the count because if the ops->store doesn't read
    everything it will do something weird:

    For example, if we have ' 123 ' and ops->store read only one char,
    then the function will return 7 (1 leading + 4 trailing + 1 read). For
    the next call the buffer will be filled only by spaces which is
    incorrect (it should be '23 ').

    > diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
    > --- a/fs/sysfs/file.c
    > +++ b/fs/sysfs/file.c
    > @@ -6,6 +6,7 @@
    > #include <linux/fsnotify.h>
    > #include <linux/kobject.h>
    > #include <linux/namei.h>
    > +#include <linux/ctype.h>
    > #include <asm/uaccess.h>
    > #include <asm/semaphore.h>
    >
    > @@ -207,8 +208,28 @@ flush_write_buffer(struct dentry * dentr
    > struct attribute * attr = to_attr(dentry);
    > struct kobject * kobj = to_kobj(dentry->d_parent);
    > struct sysfs_ops * ops = buffer->ops;
    > + int ws_count = count;
    > + char *x;
    >
    > - return ops->store(kobj,attr,buffer->page,count);
    > + /* locate trailing white space */
    > + while ((count > 0) && isspace(buffer->page[count - 1]))
    > + count--;
    > +
    > + /* locate leading white space */
    > + x = buffer->page;
    > + if (count > 0) {
    > + while (isspace(*x))
    > + x++;
    > + count -= (x - buffer->page);
    > + }
    > + /* terminate the string */
    > + x[count] = '\0';
    what if count == PAGE_SIZE ?
    > + ws_count -= count;
    > +
    > + if (count != 0)
    > + count = ops->store(kobj, attr, x, count);
    > +
    > + return count + ws_count;
    return (count < 0) ? count : count + ws_count;
    > }
    >
    >
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