Re: [ndctl PATCH v4 09/17] util/hexdump: Add a util helper to print a buffer in hex

[Dan Williams <dan.j.williams@intel.com>]

On Thu, Oct 7, 2021 at 1:22 AM Vishal Verma <vishal.l.verma@intel.com> wrote:
>
> In preparation for tests that may need to set, retrieve, and display
> opaque data, add a hexdump function in util/
>
> Cc: Ben Widawsky <ben.widawsky@intel.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
> ---
>  util/hexdump.h |  8 ++++++++
>  util/hexdump.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++

If this is just for tests shouldn't it go in tests/ with the other
common test helpers? If it stays in util/ I would kind of expect it to
use the log infrastructure, no?

Other than that looks ok to me:

Reviewed-by: Dan Williams <dan.j.williams@intel.com>

>  2 files changed, 61 insertions(+)
>  create mode 100644 util/hexdump.h
>  create mode 100644 util/hexdump.c
>
> diff --git a/util/hexdump.h b/util/hexdump.h
> new file mode 100644
> index 0000000..d322b6a
> --- /dev/null
> +++ b/util/hexdump.h
> @@ -0,0 +1,8 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright (C) 2021 Intel Corporation. All rights reserved. */
> +#ifndef _UTIL_HEXDUMP_H_
> +#define _UTIL_HEXDUMP_H_
> +
> +void hex_dump_buf(unsigned char *buf, int size);
> +
> +#endif /* _UTIL_HEXDUMP_H_*/
> diff --git a/util/hexdump.c b/util/hexdump.c
> new file mode 100644
> index 0000000..1ab0118
> --- /dev/null
> +++ b/util/hexdump.c
> @@ -0,0 +1,53 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (C) 2015-2021 Intel Corporation. All rights reserved. */
> +#include <stdio.h>
> +#include <util/hexdump.h>
> +
> +static void print_separator(int len)
> +{
> +       int i;
> +
> +       for (i = 0; i < len; i++)
> +               fprintf(stderr, "-");
> +       fprintf(stderr, "\n");
> +}
> +
> +void hex_dump_buf(unsigned char *buf, int size)
> +{
> +       int i;
> +       const int grp = 4;  /* Number of bytes in a group */
> +       const int wid = 16; /* Bytes per line. Should be a multiple of grp */
> +       char ascii[wid + 1];
> +
> +       /* Generate header */
> +       print_separator((wid * 4) + (wid / grp) + 12);
> +
> +       fprintf(stderr, "Offset    ");
> +       for (i = 0; i < wid; i++) {
> +               if (i % grp == 0) fprintf(stderr, " ");
> +               fprintf(stderr, "%02x ", i);
> +       }
> +       fprintf(stderr, "  Ascii\n");
> +
> +       print_separator((wid * 4) + (wid / grp) + 12);
> +
> +       /* Generate hex dump */
> +       for (i = 0; i < size; i++) {
> +               if (i % wid == 0) fprintf(stderr, "%08x  ", i);
> +               ascii[i % wid] =
> +                   ((buf[i] >= ' ') && (buf[i] <= '~')) ? buf[i] : '.';
> +               if (i % grp == 0) fprintf(stderr, " ");
> +               fprintf(stderr, "%02x ", buf[i]);
> +               if ((i == size - 1) && (size % wid != 0)) {
> +                       int j;
> +                       int done = size % wid;
> +                       int grps_done = (done / grp) + ((done % grp) ? 1 : 0);
> +                       int spaces = wid / grp - grps_done + ((wid - done) * 3);
> +
> +                       for (j = 0; j < spaces; j++) fprintf(stderr, " ");
> +               }
> +               if ((i % wid == wid - 1) || (i == size - 1))
> +                       fprintf(stderr, "  %.*s\n", (i % wid) + 1, ascii);
> +       }
> +       print_separator((wid * 4) + (wid / grp) + 12);
> +}
> --
> 2.31.1
>