[PATCH 10/15] cmd: blk_common: Use macros for the return values

[Bin Meng]

Hi Simon,

On Mon, Oct 2, 2023 at 9:42 AM Simon Glass <sjg at chromium.org> wrote:
>
> Hi Bin,
>
> On Tue, 26 Sept 2023 at 02:54, Bin Meng <bmeng at tinylab.org> wrote:
> >
> > Avoid using magic number 0/1 for the command result.
> >
> > Signed-off-by: Bin Meng <bmeng at tinylab.org>
> > ---
> >
> >  cmd/blk_common.c | 14 +++++++-------
> >  1 file changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/cmd/blk_common.c b/cmd/blk_common.c
> > index 9f9d4327a9..ad9b16dc09 100644
> > --- a/cmd/blk_common.c
> > +++ b/cmd/blk_common.c
> > @@ -25,18 +25,18 @@ int blk_common_cmd(int argc, char *const argv[], enum uclass_id uclass_id,
> >         case 2:
> >                 if (strncmp(argv[1], "inf", 3) == 0) {
> >                         blk_list_devices(uclass_id);
> > -                       return 0;
> > +                       return CMD_RET_SUCCESS;
>
> I really don't like this...0 is success.
>
> >                 } else if (strncmp(argv[1], "dev", 3) == 0) {
> >                         if (blk_print_device_num(uclass_id, *cur_devnump)) {
> >                                 printf("\nno %s devices available\n", if_name);
> >                                 return CMD_RET_FAILURE;
> >                         }
> > -                       return 0;
> > +                       return CMD_RET_SUCCESS;
> >                 } else if (strncmp(argv[1], "part", 4) == 0) {
> >                         if (blk_list_part(uclass_id))
> >                                 printf("\nno %s partition table available\n",
> >                                        if_name);
> > -                       return 0;
> > +                       return CMD_RET_SUCCESS;
> >                 }
> >                 return CMD_RET_USAGE;
> >         case 3:
> > @@ -49,7 +49,7 @@ int blk_common_cmd(int argc, char *const argv[], enum uclass_id uclass_id,
> >                         } else {
> >                                 return CMD_RET_FAILURE;
> >                         }
> > -                       return 0;
> > +                       return CMD_RET_SUCCESS;
> >                 } else if (strncmp(argv[1], "part", 4) == 0) {
> >                         int dev = (int)dectoul(argv[2], NULL);
> >
> > @@ -58,7 +58,7 @@ int blk_common_cmd(int argc, char *const argv[], enum uclass_id uclass_id,
> >                                        if_name, dev);
> >                                 return CMD_RET_FAILURE;
> >                         }
> > -                       return 0;
> > +                       return CMD_RET_SUCCESS;
> >                 }
> >                 return CMD_RET_USAGE;
> >
> > @@ -80,7 +80,7 @@ int blk_common_cmd(int argc, char *const argv[], enum uclass_id uclass_id,
> >
> >                         printf("%ld blocks read: %s\n", n,
> >                                n == cnt ? "OK" : "ERROR");
> > -                       return n == cnt ? 0 : 1;
> > +                       return n == cnt ? CMD_RET_SUCCESS : CMD_RET_FAILURE;
>
> CMD_RET_FAILURE is OK, but I would prefer not to use CMD_RET_SUCCESS.
> It is 0 and always will be.
>
> It encourages people to do things like:
>
> if (ret == CMD_RET_SUCCESS)
>
> instead of
>
> if (!ret)

I see your concern. However we don't change the return value type to
enum, so people can still use

    if (!ret)

I would still defend that we should use CMD_RET_SUCCESS.

This is like EXIT_XXX defined in stdlib.h:

#define   EXIT_FAILURE   1    /* Failing exit status.  */
#define   EXIT_SUCCESS   0    /* Successful exit status.  */

One should use predefined macros whenever possible.

>
> It would eventually creep into everything, including our clean error handling.
>
> >                 } else if (strcmp(argv[1], "write") == 0) {
> >                         phys_addr_t paddr = hextoul(argv[2], NULL);
> >                         lbaint_t blk = hextoul(argv[3], NULL);
> > @@ -98,7 +98,7 @@ int blk_common_cmd(int argc, char *const argv[], enum uclass_id uclass_id,
> >
> >                         printf("%ld blocks written: %s\n", n,
> >                                n == cnt ? "OK" : "ERROR");
> > -                       return n == cnt ? 0 : 1;
> > +                       return n == cnt ? CMD_RET_SUCCESS : CMD_RET_FAILURE;
> >                 } else {
> >                         return CMD_RET_USAGE;
> >                 }
> > --

Regards,
Bin