Re: [PATCH 2/2] jffs2: fix buffer dump debug output

[Joe Perches <joe@perches.com>]

On Tue, 2014-10-21 at 10:05 +0200, Cyrille Pitchen wrote:
> This patch fixes __jffs2_dbg_dump_buffer(): this function prints a message
> claiming to dump len bytes. However, depending on the start offset, the former
> code drops up to 31 (JFFS2_BUFDUMP_BYTES_PER_LINE - 1) bytes.
> 
> Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
> ---
>  fs/jffs2/debug.c | 21 ++++++++-------------
>  1 file changed, 8 insertions(+), 13 deletions(-)
> 
> diff --git a/fs/jffs2/debug.c b/fs/jffs2/debug.c
> index 07bd5bc..1b515b2 100644
> --- a/fs/jffs2/debug.c
> +++ b/fs/jffs2/debug.c
> @@ -736,30 +736,25 @@ void
>  __jffs2_dbg_dump_buffer(unsigned char *buf, int len, uint32_t offs)
>  {
>  	int skip;
> -	int i;
> +	int i, pos;
>  
>  	printk(JFFS2_DBG_MSG_PREFIX " dump from offset %#08x to offset %#08x (%x bytes).\n",
>  		offs, offs + len, len);
> -	i = skip = offs % JFFS2_BUFDUMP_BYTES_PER_LINE;
> +	i = skip = offs & (JFFS2_BUFDUMP_BYTES_PER_LINE - 1);
>  	offs = offs & ~(JFFS2_BUFDUMP_BYTES_PER_LINE - 1);
>  
> -	if (skip != 0)
> -		printk(JFFS2_DBG "%#08x: ", offs);
> -
> +	printk(JFFS2_DBG "%#08x: ", offs);
>  	while (skip--)
>  		printk("   ");
>  
> -	while (i < len) {
> -		if ((i % JFFS2_BUFDUMP_BYTES_PER_LINE) == 0 && i != len -1) {
> -			if (i != 0)
> -				printk("\n");
> +	for (pos = 0; pos < len; ++pos, ++i) {
> +		if (i == JFFS2_BUFDUMP_BYTES_PER_LINE) {
>  			offs += JFFS2_BUFDUMP_BYTES_PER_LINE;
> -			printk(JFFS2_DBG "%0#8x: ", offs);
> +			printk(JFFS2_DBG "\n%0#8x: ", offs);
> +			i = 0;

print_hex_dump would be better