[Libguestfs] [PATCH] fish: help command return error for non-existent commands (RHBZ#597145).

[Matthew Booth]

On 01/06/10 16:30, Richard W.M. Jones wrote:
>> From ea5c6cf0341fdd8072b12723f9794506841bc688 Mon Sep 17 00:00:00 2001
> From: Richard Jones<rjones at redhat.com>
> Date: Tue, 1 Jun 2010 16:27:33 +0100
> Subject: [PATCH] fish: help command return error for non-existent commands (RHBZ#597145).
>
> With this change, the exit status indicates error for non-existent
> commands.
>
> $ guestfish -h foo
> foo: command not known, use -h to list all commands
> $ echo $?
> 1
> $ guestfish help foo
> foo: command not known, use -h to list all commands
> $ echo $?
> 1
> ---
>   fish/fish.c      |   78 ++++++++++++++++++++++++++++++++++++++----------------
>   fish/fish.h      |    4 +-
>   src/generator.ml |    8 +++--
>   3 files changed, 62 insertions(+), 28 deletions(-)
>
> diff --git a/fish/fish.c b/fish/fish.c
> index 557a6ac..470c625 100644
> --- a/fish/fish.c
> +++ b/fish/fish.c
> @@ -1166,7 +1190,9 @@ display_builtin_command (const char *cmd)
>                 "\n"
>                 "    Size can be specified using standard suffixes, eg. '1M'.\n"
>                 ));
> -  else if (STRCASEEQ (cmd, "supported"))
> +    return 0;
> +  }
> +  else if (STRCASEEQ (cmd, "supported")) {
>       printf (_("supported - list supported groups of commands\n"
>                 "     supported\n"
>                 "\n"
> @@ -1176,15 +1202,21 @@ display_builtin_command (const char *cmd)
>                 "\n"
>                 "    See also guestfs(3) section AVAILABILITY.\n"
>                 ));
> -  else if (STRCASEEQ (cmd, "time"))
> +    return 0;
> +  }
> +  else if (STRCASEEQ (cmd, "time")) {
>       printf (_("time - measure time taken to run command\n"
>                 "    time<command>  [<args>  ...]\n"
>                 "\n"
>                 "    This runs<command>  as usual, and prints the elapsed\n"
>                 "    time afterwards.\n"));
> -  else
> +    return 0;
> +  }
> +  else {
>       fprintf (stderr, _("%s: command not known, use -h to list all commands\n"),
>                cmd);
> +    return -1;
> +  }
>   }

You could get rid of all of the above 'return 0' statements by allowing 
them to fall through and having a single 'return 0' at the end of the 
function. This would also be clearer IMHO.

On a related note, I'd still put curlies round all the single-line if 
statements.


>
>   /* This is printed when the user types in an unknown command for the
> diff --git a/fish/fish.h b/fish/fish.h
> index b98faf0..9f64979 100644
> --- a/fish/fish.h
> +++ b/fish/fish.h
> @@ -55,7 +55,7 @@ extern int command_num;
>   extern int issue_command (const char *cmd, char *argv[], const char *pipe);
>   extern void pod2text (const char *name, const char *shortdesc, const char *body);
>   extern void list_builtin_commands (void);
> -extern void display_builtin_command (const char *cmd);
> +extern int display_builtin_command (const char *cmd);
>   extern void free_strings (char **argv);
>   extern int count_strings (char *const *argv);
>   extern void print_strings (char *const *argv);
> @@ -71,7 +71,7 @@ extern void extended_help_message (void);
>
>   /* in cmds.c (auto-generated) */
>   extern void list_commands (void);
> -extern void display_command (const char *cmd);
> +extern int display_command (const char *cmd);
>   extern int run_action (const char *cmd, int argc, char *argv[]);
>
>   /* in completion.c (auto-generated) */
> diff --git a/src/generator.ml b/src/generator.ml
> index 2c33049..571ea3a 100755
> --- a/src/generator.ml
> +++ b/src/generator.ml
> @@ -7575,7 +7575,7 @@ and generate_fish_cmds () =
>     pr "\n";
>
>     (* display_command function, which implements guestfish -h cmd *)
> -  pr "void display_command (const char *cmd)\n";
> +  pr "int display_command (const char *cmd)\n";
>     pr "{\n";
>     List.iter (
>       fun (name, style, _, flags, _, shortdesc, longdesc) ->
> @@ -7623,15 +7623,17 @@ and generate_fish_cmds () =
>           pr " || STRCASEEQ (cmd, \"%s\")" name2;
>         if name<>  alias then
>           pr " || STRCASEEQ (cmd, \"%s\")" alias;
> -      pr ")\n";
> +      pr ") {\n";
>         pr "    pod2text (\"%s\", _(\"%s\"), %S);\n"
>           name2 shortdesc
>           ("=head1 SYNOPSIS\n\n " ^ synopsis ^ "\n\n" ^
>            "=head1 DESCRIPTION\n\n" ^
>            longdesc ^ warnings ^ describe_alias);
> +      pr "    return 0;\n";
> +      pr "  }\n";
>         pr "  else\n"
>     ) all_functions;
> -  pr "    display_builtin_command (cmd);\n";
> +  pr "    return display_builtin_command (cmd);\n";
>     pr "}\n";
>     pr "\n";

I guess it doesn't matter so much here, though.

Apart from the style point, though, ACK.

Matt
-- 
Matthew Booth, RHCA, RHCSS
Red Hat Engineering, Virtualisation Team

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