> Wenchao Xia <xiaw...@linux.vnet.ibm.com> writes:
>
>> This patch make parsing of hmp command aware of that it may
>> have sub command. Also discard simple encapsulation function
>> monitor_find_command() and qmp_find_cmd().
>>
>> Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com>
>> ---
>> monitor.c | 31 +++++++++++++++++++++++--------
>> 1 files changed, 23 insertions(+), 8 deletions(-)
>>
>> diff --git a/monitor.c b/monitor.c
>> index c7b3014..d49a362 100644
>> --- a/monitor.c
>> +++ b/monitor.c
>> @@ -130,6 +130,7 @@ typedef struct mon_cmd_t {
>> MonitorCompletion *cb, void *opaque);
>> } mhandler;
>> int flags;
>> + struct mon_cmd_t *sub_table;
>> } mon_cmd_t;
>>
>> /* file descriptors passed via SCM_RIGHTS */
>> @@ -3534,21 +3535,22 @@ static const mon_cmd_t *search_dispatch_table(const
>> mon_cmd_t *disp_table,
>> return NULL;
>> }
>>
>> -static const mon_cmd_t *monitor_find_command(const char *cmdname)
>> -{
>> - return search_dispatch_table(mon_cmds, cmdname);
>> -}
>> -
>> static const mon_cmd_t *qmp_find_cmd(const char *cmdname)
>> {
>> return search_dispatch_table(qmp_cmds, cmdname);
>> }
>>
>> +/*
>> + * Try find the target mon_cmd_t instance. If it have sub_table and have
>> string
>> + * for it, this function will try search it with remaining string, and if
>> not
>> + * found it return NULL.
>> + */
>
> Thanks for going the extra mile and document the function. What about:
>
> /*
> * Parse @cmdline according to command table @table.
> * If @cmdline is blank, return NULL.
> * If it can't be parsed, report to @mon, and return NULL.
> * Else, insert command arguments into @qdict, and return the command.
> * Do not assume the returned command points into @table! It doesn't
> * when the command is a sub-command.
> */
>
OK, I'll use it in V5.
>> static const mon_cmd_t *monitor_parse_command(Monitor *mon,
>> const char *cmdline,
>> + mon_cmd_t *table,
>> QDict *qdict)
>> {
>> - const char *p, *typestr;
>> + const char *p, *p1, *typestr;
>> int c;
>> const mon_cmd_t *cmd;
>> char cmdname[256];
>> @@ -3564,12 +3566,25 @@ static const mon_cmd_t
>> *monitor_parse_command(Monitor *mon,
>> if (!p)
>> return NULL;
>>
>> - cmd = monitor_find_command(cmdname);
>> + cmd = search_dispatch_table(table, cmdname);
>> if (!cmd) {
>> monitor_printf(mon, "unknown command: '%s'\n", cmdname);
>> return NULL;
>> }
>>
>> + /* search sub command */
>> + if (cmd->sub_table != NULL) {
>> + p1 = p;
>> + /* check if user set additional command */
>> + while (qemu_isspace(*p1)) {
>> + p1++;
>> + }
>> + if (*p1 == '\0') {
>> + return cmd;
>> + }
>> + return monitor_parse_command(mon, p, cmd->sub_table, qdict);
>> + }
>> +
>> /* parse the parameters */
>> typestr = cmd->args_type;
>> for(;;) {
>
> The check whether non-space characters follow is awkward. We need it
> only because we want to handle "@cmdline is blank" differently than "it
> can't be parsed", but monitor_parse_command() returns NULL for both
> cases. If we care, we can try to do better in a follow-up patch.
>
Yes it is checked to avoid getting NULL for case "info ". I'll split
up a patch for the check code.
> We'll get sub-optimal error messages when the infrastructure is put to
> use in patch 4/4, e.g.:
>
> (qemu) info apple pie
> unknown command: 'apple'
>
> That's because cmdname is just "apple" at the place where the error is
> diagnosed.
>
> Several other messages also print cmdname, and thus are similarly
> affected. Many of them could probably just omit printing it, but that's
> a separate issue.
>
> A possible way to improve this: additional parameter int start, parse
> starts at cmdline + start, and instead of printing cmdname, print
> cmdline up to end of cmdname. Something like
>
> monitor_printf(mon, "unknown command: '%.*s'\n",
> (int)(p - cmdline), cmdline);
>
Thanks, I think this could work.
>> @@ -3925,7 +3940,7 @@ static void handle_user_command(Monitor *mon, const
>> char *cmdline)
>>
>> qdict = qdict_new();
>>
>> - cmd = monitor_parse_command(mon, cmdline, qdict);
>> + cmd = monitor_parse_command(mon, cmdline, mon_cmds, qdict);
>> if (!cmd)
>> goto out;
>
--
Best Regards
Wenchao Xia
