linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * seq_buf.c

 *

 * Copyright (C) 2014 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>

 *

 * The seq_buf is a handy tool that allows you to pass a descriptor around

 * to a buffer that other functions can write to. It is similar to the

 * seq_file functionality but has some differences.

 *

 * To use it, the seq_buf must be initialized with seq_buf_init().

 * This will set up the counters within the descriptor. You can call

 * seq_buf_init() more than once to reset the seq_buf to start

 * from scratch.

 */

#include <linux/uaccess.h>

#include <linux/seq_file.h>

#include <linux/seq_buf.h>

​

/**

 * seq_buf_can_fit - can the new data fit in the current buffer?

 * @s: the seq_buf descriptor

 * @len: The length to see if it can fit in the current buffer

 *

 * Returns true if there's enough unused space in the seq_buf buffer

 * to fit the amount of new data according to @len.

 */

static bool seq_buf_can_fit(struct seq_buf *s, size_t len)

{

    return s->len + len <= s->size;

}

​

/**

 * seq_buf_print_seq - move the contents of seq_buf into a seq_file

 * @m: the seq_file descriptor that is the destination

 * @s: the seq_buf descriptor that is the source.

 *

 * Returns zero on success, non zero otherwise

 */

int seq_buf_print_seq(struct seq_file *m, struct seq_buf *s)

{

    unsigned int len = seq_buf_used(s);

​

    return seq_write(m, s->buffer, len);

}

​

/**

 * seq_buf_vprintf - sequence printing of information.

 * @s: seq_buf descriptor

 * @fmt: printf format string

 * @args: va_list of arguments from a printf() type function

 *

 * Writes a vnprintf() format into the sequencce buffer.

 *

 * Returns zero on success, -1 on overflow.

 */

int seq_buf_vprintf(struct seq_buf *s, const char *fmt, va_list args)

{

    int len;

​

    WARN_ON(s->size == 0);

​

    if (s->len < s->size) {