perf tools: Introduce perf_target__strerror()
The perf_target__strerror() sets @buf to a string that describes the
(perf_target-specific) error condition that is passed via @errnum.
This is similar to strerror_r() and does same thing if @errnum has a
standard errno value.
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1336367344-28071-6-git-send-email-namhyung.kim@lge.com
[ committer note: No need to use PERF_ERRNO_TARGET__SUCCESS, use shorter idiom ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c
index 02a6bed..1064d5b 100644
--- a/tools/perf/util/target.c
+++ b/tools/perf/util/target.c
@@ -10,6 +10,7 @@
#include "debug.h"
#include <pwd.h>
+#include <string.h>
enum perf_target_errno perf_target__validate(struct perf_target *target)
@@ -89,3 +90,53 @@
target->uid = result->pw_uid;
return PERF_ERRNO_TARGET__SUCCESS;
}
+
+/*
+ * This must have a same ordering as the enum perf_target_errno.
+ */
+static const char *perf_target__error_str[] = {
+ "PID/TID switch overriding CPU",
+ "PID/TID switch overriding UID",
+ "UID switch overriding CPU",
+ "PID/TID switch overriding SYSTEM",
+ "UID switch overriding SYSTEM",
+ "Invalid User: %s",
+ "Problems obtaining information for user %s",
+};
+
+int perf_target__strerror(struct perf_target *target, int errnum,
+ char *buf, size_t buflen)
+{
+ int idx;
+ const char *msg;
+
+ if (errnum >= 0) {
+ strerror_r(errnum, buf, buflen);
+ return 0;
+ }
+
+ if (errnum < __PERF_ERRNO_TARGET__START ||
+ errnum >= __PERF_ERRNO_TARGET__END)
+ return -1;
+
+ idx = errnum - __PERF_ERRNO_TARGET__START;
+ msg = perf_target__error_str[idx];
+
+ switch (errnum) {
+ case PERF_ERRNO_TARGET__PID_OVERRIDE_CPU
+ ... PERF_ERRNO_TARGET__UID_OVERRIDE_SYSTEM:
+ snprintf(buf, buflen, "%s", msg);
+ break;
+
+ case PERF_ERRNO_TARGET__INVALID_UID:
+ case PERF_ERRNO_TARGET__USER_NOT_FOUND:
+ snprintf(buf, buflen, msg, target->uid_str);
+ break;
+
+ default:
+ /* cannot reach here */
+ break;
+ }
+
+ return 0;
+}