perf tools: Enhance the matching of sub-commands abbreviations

We support short command 'rec*' for 'record' and 'rep*' for 'report' in
lots of sub-commands, but the matching is not quite strict currnetly.

It may be puzzling sometime, like we mis-type a 'recport' to report but
it will perform 'record' in fact without any message.

To fix this, add a check to ensure that the short cmd is valid prefix
of the real command.

Committer testing:

  [root@quaco ~]# perf c2c re sleep 1

   Usage: perf c2c {record|report}

      -v, --verbose         be more verbose (show counter open errors, etc)

  # perf c2c rec sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.038 MB perf.data (16 samples) ]
  # perf c2c recport sleep 1

   Usage: perf c2c {record|report}

      -v, --verbose         be more verbose (show counter open errors, etc)

  # perf c2c record sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.038 MB perf.data (15 samples) ]
  # perf c2c records sleep 1

   Usage: perf c2c {record|report}

      -v, --verbose         be more verbose (show counter open errors, etc)

  #

Signed-off-by: Wei Li <liwei391@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Rui Xiang <rui.xiang@huawei.com>
Link: http://lore.kernel.org/lkml/20220325092032.2956161-1-liwei391@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 5 insertions, 4 deletions

diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index b23a1f3eaeda..2fa687f73e5e 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -24,6 +24,7 @@
 #include "util/ordered-events.h"
 #include "util/kvm-stat.h"
 #include "ui/ui.h"
+#include "util/string2.h"
 
 #include <sys/prctl.h>
 #ifdef HAVE_TIMERFD_SUPPORT
@@ -1500,10 +1501,10 @@ static int kvm_cmd_stat(const char *file_name, int argc, const char **argv)
 		goto perf_stat;
 	}
 
-	if (!strncmp(argv[1], "rec", 3))
+	if (strlen(argv[1]) > 2 && strstarts("record", argv[1]))
 		return kvm_events_record(&kvm, argc - 1, argv + 1);
 
-	if (!strncmp(argv[1], "rep", 3))
+	if (strlen(argv[1]) > 2 && strstarts("report", argv[1]))
 		return kvm_events_report(&kvm, argc - 1 , argv + 1);
 
 #ifdef HAVE_TIMERFD_SUPPORT
@@ -1631,9 +1632,9 @@ int cmd_kvm(int argc, const char **argv)
 		}
 	}
 
-	if (!strncmp(argv[0], "rec", 3))
+	if (strlen(argv[0]) > 2 && strstarts("record", argv[0]))
 		return __cmd_record(file_name, argc, argv);
-	else if (!strncmp(argv[0], "rep", 3))
+	else if (strlen(argv[0]) > 2 && strstarts("report", argv[0]))
 		return __cmd_report(file_name, argc, argv);
 	else if (!strncmp(argv[0], "diff", 4))
 		return cmd_diff(argc, argv);