[COMMITTED] Print strlen benchmark output in json

diff --git a/ChangeLog b/ChangeLog
index dedffaa9d3..ec444a339e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@ 
+2018-08-16  Siddhesh Poyarekar  <siddhesh@sourceware.org>
+
+	* benchtests/bench-strlen.c: Print performance numbers in json.
+
 2018-08-16  Rajalakshmi Srinivasaraghavan  <raji@linux.vnet.ibm.com>
 
 	* sysdeps/powerpc/powerpc64/multiarch/Makefile
diff --git a/benchtests/bench-strlen.c b/benchtests/bench-strlen.c
index 215b5bb6e1..6782215e7e 100644
--- a/benchtests/bench-strlen.c
+++ b/benchtests/bench-strlen.c
@@ -35,6 +35,8 @@ 
 # define MAX_CHAR WCHAR_MAX
 #endif
 
+#include "json-lib.h"
+
 typedef size_t (*proto_t) (const CHAR *);
 
 size_t
@@ -60,7 +62,7 @@  IMPL (STRLEN, 1)
 
 
 static void
-do_one_test (impl_t *impl, const CHAR *s, size_t exp_len)
+do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s, size_t exp_len)
 {
   size_t len = CALL (impl, s), i, iters = INNER_LOOP_ITERS;
   timing_t start, stop, cur;
@@ -82,11 +84,11 @@  do_one_test (impl_t *impl, const CHAR *s, size_t exp_len)
 
   TIMING_DIFF (cur, start, stop);
 
-  TIMING_PRINT_MEAN ((double) cur, (double) iters);
+  json_element_double (json_ctx, (double) cur / (double) iters);
 }
 
 static void
-do_test (size_t align, size_t len)
+do_test (json_ctx_t *json_ctx, size_t align, size_t len)
 {
   size_t i;
 
@@ -100,42 +102,63 @@  do_test (size_t align, size_t len)
     buf[align + i] = 1 + 11111 * i % MAX_CHAR;
   buf[align + len] = 0;
 
-  printf ("Length %4zd, alignment %2zd:", len, align);
+  json_element_object_begin (json_ctx);
+  json_attr_uint (json_ctx, "length", len);
+  json_attr_uint (json_ctx, "alignment", align);
+  json_array_begin (json_ctx, "timings");
+
 
   FOR_EACH_IMPL (impl, 0)
-    do_one_test (impl, (CHAR *) (buf + align), len);
+    do_one_test (json_ctx, impl, (CHAR *) (buf + align), len);
 
-  putchar ('\n');
+  json_array_end (json_ctx);
+  json_element_object_end (json_ctx);
 }
 
 int
 test_main (void)
 {
+  json_ctx_t json_ctx;
   size_t i;
 
   test_init ();
 
-  printf ("%20s", "");
+  json_init (&json_ctx, 0, stdout);
+
+  json_document_begin (&json_ctx);
+  json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
+
+  json_attr_object_begin (&json_ctx, "functions");
+  json_attr_object_begin (&json_ctx, TEST_NAME);
+  json_attr_string (&json_ctx, "bench-variant", "");
+
+  json_array_begin (&json_ctx, "ifuncs");
   FOR_EACH_IMPL (impl, 0)
-    printf ("\t%s", impl->name);
-  putchar ('\n');
+    json_element_string (&json_ctx, impl->name);
+  json_array_end (&json_ctx);
 
+  json_array_begin (&json_ctx, "results");
   /* Checking with only 4 * N alignments for wcslen, other alignments are wrong for wchar_t type arrays*/
 
   for (i = 1; i < 8; ++i)
   {
-    do_test (sizeof(CHAR) * i, i);
-    do_test (0, i);
+    do_test (&json_ctx, sizeof(CHAR) * i, i);
+    do_test (&json_ctx, 0, i);
   }
 
   for (i = 2; i <= 12; ++i)
     {
-      do_test (0, 1 << i);
-      do_test (sizeof(CHAR) * 7, 1 << i);
-      do_test (sizeof(CHAR) * i, 1 << i);
-      do_test (sizeof(CHAR) * i, (size_t)((1 << i) / 1.5));
+      do_test (&json_ctx, 0, 1 << i);
+      do_test (&json_ctx, sizeof(CHAR) * 7, 1 << i);
+      do_test (&json_ctx, sizeof(CHAR) * i, 1 << i);
+      do_test (&json_ctx, sizeof(CHAR) * i, (size_t)((1 << i) / 1.5));
     }
 
+  json_array_end (&json_ctx);
+  json_attr_object_end (&json_ctx);
+  json_attr_object_end (&json_ctx);
+  json_document_end (&json_ctx);
+
   return ret;
 }