[PATCH v1 1/1] cmd: setexpr: add dec operation for converting variable to decimal

[Sean Anderson]

On 6/22/21 3:25 PM, Simon Glass wrote:
 > Hi Roland,
 >
 > On Tue, 22 Jun 2021 at 07:51, <roland.gaudig-oss at weidmueller.com> wrote:
 >>
 >> From: Roland Gaudig <roland.gaudig at weidmueller.com>
 >>
 >> This patch extends the setexpr command with a dec operator to
 >> convert an input value to decimal.
 >>
 >> Signed-off-by: Roland Gaudig <roland.gaudig at weidmueller.com>
 >> ---
 >>
 >>  cmd/setexpr.c | 16 ++++++++++++++--
 >>  1 file changed, 14 insertions(+), 2 deletions(-)
 >>
 >> diff --git a/cmd/setexpr.c b/cmd/setexpr.c
 >> index e828be3970..2d4bee2182 100644
 >> --- a/cmd/setexpr.c
 >> +++ b/cmd/setexpr.c
 >> @@ -370,15 +370,16 @@ static int do_setexpr(struct cmd_tbl *cmdtp, int flag, int argc,
 >>         int w;
 >>
 >>         /*
 >> -        * We take 3, 5, or 6 arguments:
 >> +        * We take 3, 4, 5, or 6 arguments:
 >>          * 3 : setexpr name value
 >> +        * 4 : setexpr name dec value
 >>          * 5 : setexpr name val1 op val2
 >>          *     setexpr name [g]sub r s
 >>          * 6 : setexpr name [g]sub r s t
 >>          */
 >>
 >>         /* > 6 already tested by max command args */
 >> -       if ((argc < 3) || (argc == 4))
 >> +       if (argc < 3)
 >>                 return CMD_RET_USAGE;
 >>
 >>         w = cmd_get_data_size(argv[0], 4);
 >> @@ -398,6 +399,13 @@ static int do_setexpr(struct cmd_tbl *cmdtp, int flag, int argc,
 >>                 return ret;
 >>         }
 >>
 >> +       /* hexadecimal to decimal conversion: "setexpr name dec value" */
 >> +       if (argc == 4 && (strcmp(argv[2], "dec") == 0)) {
 >> +               w = cmd_get_data_size(argv[3], 4);
 >> +               a = get_arg(argv[3], w);
 >> +               return env_set_ulong(argv[1], a);
 >> +       }
 >> +
 >>         /* 5 or 6 args (6 args only with [g]sub) */
 >>  #ifdef CONFIG_REGEX
 >>         /*
 >> @@ -515,4 +523,8 @@ U_BOOT_CMD(
 >>         "setexpr name sub r s [t]\n"
 >>         "    - Just like gsub(), but replace only the first matching substring"
 >>  #endif
 >> +       "\n"
 >> +       "setexpr name dec [*]value\n"
 >> +       "    - set environment variable 'name' to the result of the decimal\n"
 >> +       "      conversion of [*]value.\n"
 >>  );
 >> --
 >> 2.25.1
 >>
 >
 > This seems reasonable to me.
 >
 > I have been thinking of introducing a prefix for decimal, perhaps
 > 0m123 ? ('m' for deciMal).

Perhaps 0d123? Though I would prefer to remove many of the implicit
assumptions of hex input.

--Sean

 >
 > Can you please add a test for this in test//cmd/setexpr.c and also,
 > how about adding something in doc/usage?
 >
 > Regards,
 > Simon
 >