perf util: Add parse_nsec_time() function
The parse_nsec_time() function is for parsing a string of time into
64-bit nsec value. It's a preparation of time filtering in some of perf
commands.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: David Ahern <dsahern@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1370310629-9642-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 9a06584..6d17b18 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -328,3 +328,36 @@
{
free(file);
}
+
+int parse_nsec_time(const char *str, u64 *ptime)
+{
+ u64 time_sec, time_nsec;
+ char *end;
+
+ time_sec = strtoul(str, &end, 10);
+ if (*end != '.' && *end != '\0')
+ return -1;
+
+ if (*end == '.') {
+ int i;
+ char nsec_buf[10];
+
+ if (strlen(++end) > 9)
+ return -1;
+
+ strncpy(nsec_buf, end, 9);
+ nsec_buf[9] = '\0';
+
+ /* make it nsec precision */
+ for (i = strlen(nsec_buf); i < 9; i++)
+ nsec_buf[i] = '0';
+
+ time_nsec = strtoul(nsec_buf, &end, 10);
+ if (*end != '\0')
+ return -1;
+ } else
+ time_nsec = 0;
+
+ *ptime = time_sec * NSEC_PER_SEC + time_nsec;
+ return 0;
+}