[PATCH 05/11] perf script: Show proper message when failed list scripts

Arnaldo Carvalho de Melo
2016-08-15T22:01:46Z

From: He Kuang <hekuang@huawei.com>

Perf shows the usage message when perf scripts folder failed to open,
which misleads users to let them think the command is being mistyped.

This patch shows a proper message and guides users to check the
PERF_EXEC_PATH environment variable in that case.

Before:

$ perf script --list

Usage: perf script [<options>]
or: perf script [<options>] record [<record-options>] <command>
or: perf script [<options>] report [script-args]
or: perf script [<options>] [<record-options>] <command>
or: perf script [<options>] <top-script> [script-args]

-l, --list list available scripts

After:

$ perf script --list
open(/home/user/perf-core/scripts) failed.
Check for "PERF_EXEC_PATH" env to set scripts dir.

Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1470309943-153909-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-script.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 9c640a8081c7..45c51eb6cab4 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -1690,8 +1690,13 @@ static int list_available_scripts(const struct option *opt __maybe_unused,
snprintf(scripts_path, MAXPATHLEN, "%s/scripts", get_argv_exec_path());

scripts_dir = opendir(scripts_path);
- if (!scripts_dir)
- return -1;
+ if (!scripts_dir) {
+ fprintf(stdout,
+ "open(%s) failed.\n"
+ "Check \"PERF_EXEC_PATH\" env to set scripts dir.\n",
+ scripts_path);
+ exit(-1);
+ }

for_each_lang(scripts_path, scripts_dir, lang_dirent) {
snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
--
2.7.4