monitor: refine parse_cmdline()

Since this function will be used by help_cmd() later, so improve
it to make it more generic and easier to use. free_cmdline_args()
is added too as paired function to free the result.

One change of this function is that, when the valid args in input
exceed the limit of MAX_ARGS, it fails now, instead of return with
MAX_ARGS of parsed args in old code. This should not impact much
since it is rare that user input many args in monitor's "help" and
auto complete scenario.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
This commit is contained in:
Wenchao Xia 2013-08-27 20:38:22 +08:00 committed by Luiz Capitulino
parent f5438c0500
commit dcc70cdf09
1 changed files with 40 additions and 11 deletions

View File

@ -821,9 +821,33 @@ static int get_str(char *buf, int buf_size, const char **pp)
#define MAX_ARGS 16
/* NOTE: this parser is an approximate form of the real command parser */
static void parse_cmdline(const char *cmdline,
int *pnb_args, char **args)
static void free_cmdline_args(char **args, int nb_args)
{
int i;
assert(nb_args <= MAX_ARGS);
for (i = 0; i < nb_args; i++) {
g_free(args[i]);
}
}
/*
* Parse the command line to get valid args.
* @cmdline: command line to be parsed.
* @pnb_args: location to store the number of args, must NOT be NULL.
* @args: location to store the args, which should be freed by caller, must
* NOT be NULL.
*
* Returns 0 on success, negative on failure.
*
* NOTE: this parser is an approximate form of the real command parser. Number
* of args have a limit of MAX_ARGS. If cmdline contains more, it will
* return with failure.
*/
static int parse_cmdline(const char *cmdline,
int *pnb_args, char **args)
{
const char *p;
int nb_args, ret;
@ -839,16 +863,21 @@ static void parse_cmdline(const char *cmdline,
break;
}
if (nb_args >= MAX_ARGS) {
break;
goto fail;
}
ret = get_str(buf, sizeof(buf), &p);
if (ret < 0) {
goto fail;
}
args[nb_args] = g_strdup(buf);
nb_args++;
if (ret < 0) {
break;
}
}
*pnb_args = nb_args;
return 0;
fail:
free_cmdline_args(args, nb_args);
return -1;
}
static void help_cmd_dump(Monitor *mon, const mon_cmd_t *cmds,
@ -4169,7 +4198,9 @@ static void monitor_find_completion(Monitor *mon,
const mon_cmd_t *cmd;
MonitorBlockComplete mbs;
parse_cmdline(cmdline, &nb_args, args);
if (parse_cmdline(cmdline, &nb_args, args) < 0) {
return;
}
#ifdef DEBUG_COMPLETION
for (i = 0; i < nb_args; i++) {
monitor_printf(mon, "arg%d = '%s'\n", i, args[i]);
@ -4259,9 +4290,7 @@ static void monitor_find_completion(Monitor *mon,
}
cleanup:
for (i = 0; i < nb_args; i++) {
g_free(args[i]);
}
free_cmdline_args(args, nb_args);
}
static int monitor_can_read(void *opaque)