Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753061AbbBMNKS (ORCPT ); Fri, 13 Feb 2015 08:10:18 -0500 Received: from szxga01-in.huawei.com ([119.145.14.64]:56801 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752532AbbBMNKM (ORCPT ); Fri, 13 Feb 2015 08:10:12 -0500 From: Yunlong Song To: , , , CC: , Subject: [PATCH 4/7] perf list: fix a bug of segmentation fault Date: Fri, 13 Feb 2015 21:11:52 +0800 Message-ID: <1423833115-11199-5-git-send-email-yunlong.song@huawei.com> X-Mailer: git-send-email 1.8.4.5 In-Reply-To: <1423833115-11199-1-git-send-email-yunlong.song@huawei.com> References: <1423833115-11199-1-git-send-email-yunlong.song@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.110.52.30] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1450 Lines: 48 Fix the 'segmentation fault' bug of 'perf list --list-cmds', which also happens in other cases (e.g. record, report ...). This bug happens when there are no cmds to list at all. Example Before this patch: $perf list --list-cmds Segmentation fault $ After this patch: $perf list --list-cmds $ As shown above, the result prints nothing rather than a segmentation fault. The null result means 'perf list' has no cmds to display at this time. Signed-off-by: Yunlong Song --- tools/perf/util/parse-options.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/parse-options.c b/tools/perf/util/parse-options.c index 4a015f7..4ee9a86 100644 --- a/tools/perf/util/parse-options.c +++ b/tools/perf/util/parse-options.c @@ -510,8 +510,10 @@ int parse_options_subcommand(int argc, const char **argv, const struct option *o } exit(130); case PARSE_OPT_LIST_SUBCMDS: - for (int i = 0; subcommands[i]; i++) - printf("%s ", subcommands[i]); + if (subcommands) { + for (int i = 0; subcommands[i]; i++) + printf("%s ", subcommands[i]); + } exit(130); default: /* PARSE_OPT_UNKNOWN */ if (ctx.argv[0][1] == '-') { -- 1.8.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/