perf report: Don't allow empty argument for '-t'.
Without this patch, perf report cause segfault if pass "" as '-t':
$ perf report -t ""
# To display the perf.data header info, please use --header/--header-only options.
#
# Samples: 37 of event 'syscalls:sys_enter_write'
# Event count (approx.): 37
#
# Children SelfCommand Shared Object Symbol
Segmentation fault
Since -t is used to add field-separator for generate table, -t "" is
actually meanless. This patch defines a new OPT_STRING_NOEMPTY() option
generator to ensure user never pass empty string to that option.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1426251114-198991-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/parse-options.c b/tools/perf/util/parse-options.c
index 1457d66..01626be 100644
--- a/tools/perf/util/parse-options.c
+++ b/tools/perf/util/parse-options.c
@@ -37,6 +37,7 @@
{
const char *s, *arg = NULL;
const int unset = flags & OPT_UNSET;
+ int err;
if (unset && p->opt)
return opterror(opt, "takes no value", flags);
@@ -114,13 +115,29 @@
return 0;
case OPTION_STRING:
+ err = 0;
if (unset)
*(const char **)opt->value = NULL;
else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
*(const char **)opt->value = (const char *)opt->defval;
else
- return get_arg(p, opt, flags, (const char **)opt->value);
- return 0;
+ err = get_arg(p, opt, flags, (const char **)opt->value);
+
+ /* PARSE_OPT_NOEMPTY: Allow NULL but disallow empty string. */
+ if (opt->flags & PARSE_OPT_NOEMPTY) {
+ const char *val = *(const char **)opt->value;
+
+ if (!val)
+ return err;
+
+ /* Similar to unset if we are given an empty string. */
+ if (val[0] == '\0') {
+ *(const char **)opt->value = NULL;
+ return 0;
+ }
+ }
+
+ return err;
case OPTION_CALLBACK:
if (unset)