[PATCH v1 4/8] perf util: Support no index time percent slice

[Jin Yao]

Previously, the time percent slice needs an index to specify
which one the user wants.

While it may be easy for using if the index can be omitted.
So with this patch, for example,

perf report --stdio --time 10%/1 should be equivalent to
perf report --stdio --time 10%

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
 tools/perf/util/time-utils.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/tools/perf/util/time-utils.c b/tools/perf/util/time-utils.c
index 88510ab..5769f97 100644
--- a/tools/perf/util/time-utils.c
+++ b/tools/perf/util/time-utils.c
@@ -261,6 +261,37 @@ static int percent_comma_split(struct perf_time_interval *ptime_buf, int num,
 	return i;
 }
 
+static int one_percent_convert(struct perf_time_interval *ptime_buf,
+			       const char *ostr, u64 start, u64 end, char *c)
+{
+	char *str;
+	int len = strlen(ostr), ret;
+
+	/*
+	 * c points to '%'.
+	 * '%' should be the last character
+	 */
+	if (ostr + len - 1 != c)
+		return -1;
+
+	/*
+	 * Construct a string like "xx%/1"
+	 */
+	str = malloc(len + 3);
+	if (str == NULL)
+		return -ENOMEM;
+
+	memcpy(str, ostr, len);
+	strcpy(str + len, "/1");
+
+	ret = percent_slash_split(str, ptime_buf, start, end);
+	if (ret == 0)
+		ret = 1;
+
+	free(str);
+	return ret;
+}
+
 int perf_time__percent_parse_str(struct perf_time_interval *ptime_buf, int num,
 				 const char *ostr, u64 start, u64 end)
 {
@@ -270,6 +301,7 @@ int perf_time__percent_parse_str(struct perf_time_interval *ptime_buf, int num,
 	 * ostr example:
 	 * 10%/2,10%/3: select the second 10% slice and the third 10% slice
 	 * 0%-10%,30%-40%: multiple time range
+	 * 50%: just one percent
 	 */
 
 	memset(ptime_buf, 0, sizeof(*ptime_buf) * num);
@@ -286,6 +318,10 @@ int perf_time__percent_parse_str(struct perf_time_interval *ptime_buf, int num,
 					   end, percent_dash_split);
 	}
 
+	c = strchr(ostr, '%');
+	if (c)
+		return one_percent_convert(ptime_buf, ostr, start, end, c);
+
 	return -1;
 }
 
-- 
2.7.4