From: "Steven Rostedt (Red Hat)" <[email protected]> Add two helper functions; seq_buf_get_buf() and seq_buf_commit() that are used by seq_buf_path(). This makes the code similar to the seq_file: seq_path() function, and will help to be able to consolidate the functions between seq_file and trace_seq.
Signed-off-by: Steven Rostedt <[email protected]> --- include/linux/seq_buf.h | 40 ++++++++++++++++++++++++++++++++++++++++ kernel/trace/seq_buf.c | 7 +++---- 2 files changed, 43 insertions(+), 4 deletions(-) diff --git a/include/linux/seq_buf.h b/include/linux/seq_buf.h index 3cd25038cb5e..10c17c61c7a4 100644 --- a/include/linux/seq_buf.h +++ b/include/linux/seq_buf.h @@ -55,6 +55,46 @@ seq_buf_set_overflow(struct seq_buf *s) s->len = s->size + 1; } +/** + * seq_buf_get_buf - get buffer to write arbitrary data to + * @s: the seq_buf handle + * @bufp: the beginning of the buffer is stored here + * + * Return the number of bytes available in the buffer, or zero if + * there's no space. + */ +static inline size_t seq_buf_get_buf(struct seq_buf *s, char **bufp) +{ + BUG_ON(s->len > s->size + 1); + + if (s->len < s->size) { + *bufp = s->buffer + s->len; + return s->size - s->len; + } + + *bufp = NULL; + return 0; +} + +/** + * seq_buf_commit - commit data to the buffer + * @s: the seq_buf handle + * @num: the number of bytes to commit + * + * Commit @num bytes of data written to a buffer previously acquired + * by seq_buf_get. To signal an error condition, or that the data + * didn't fit in the available space, pass a negative @num value. + */ +static inline void seq_buf_commit(struct seq_buf *s, int num) +{ + if (num < 0) { + s->len = s->size; + } else { + BUG_ON(s->len + num > s->size + 1); + s->len += num; + } +} + extern __printf(2, 3) int seq_buf_printf(struct seq_buf *s, const char *fmt, ...); extern __printf(2, 0) diff --git a/kernel/trace/seq_buf.c b/kernel/trace/seq_buf.c index 06fd1833e692..d118d0d6c956 100644 --- a/kernel/trace/seq_buf.c +++ b/kernel/trace/seq_buf.c @@ -280,8 +280,8 @@ int seq_buf_putmem_hex(struct seq_buf *s, const void *mem, */ int seq_buf_path(struct seq_buf *s, const struct path *path, const char *esc) { - char *buf = s->buffer + s->len; - size_t size = SEQ_BUF_LEFT(s); + char *buf; + size_t size = seq_buf_get_buf(s, &buf); int res = -1; if (size) { @@ -292,8 +292,7 @@ int seq_buf_path(struct seq_buf *s, const struct path *path, const char *esc) res = end - buf; } } - if (res > 0) - s->len += res; + seq_buf_commit(s, res); return res; } -- 2.1.1 -- 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/
