Fix #214: mpstat: JSON output should display "all" for global CPU use

Displaying "-1" for CPU number in mpstat's JSON output format is not
consistent with what mpstat uses for other options.
So display "all" instead.

Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>

diff --git a/mpstat.c b/mpstat.c
index 9e2a393fff5aa35aed3b81edee3baa7e044cbce0..ae915a6edeac17ea6907bb62ab8c63c89703f0e3 100644 (file)
--- a/mpstat.c
+++ b/mpstat.c
@@ -652,6 +652,7 @@ void write_json_cpu_stats(int tab, unsigned long long deltot_jiffies, int prev,
                          unsigned char offline_cpu_bitmap[])
 {
        int i, next = FALSE;
+       char cpu_name[16];
        struct stats_cpu *scc, *scp;
 
        xprintf(tab++, "\"cpu-load\": [");
@@ -675,7 +676,15 @@ void write_json_cpu_stats(int tab, unsigned long long deltot_jiffies, int prev,
                }
                next = TRUE;
 
-               if (i != 0) {
+               if (i == 0) {
+                       /* This is CPU "all" */
+                       strcpy(cpu_name, "all");
+
+               }
+               else {
+                       snprintf(cpu_name, 16, "%d", i - 1);
+                       cpu_name[15] = '\0';
+
                        /* Recalculate itv for current proc */
                        deltot_jiffies = get_per_cpu_interval(scc, scp);
 
@@ -694,9 +703,9 @@ void write_json_cpu_stats(int tab, unsigned long long deltot_jiffies, int prev,
                        }
                }
 
-               xprintf0(tab, "{\"cpu\": \"%d\", \"usr\": %.2f, \"nice\": %.2f, \"sys\": %.2f, "
+               xprintf0(tab, "{\"cpu\": \"%s\", \"usr\": %.2f, \"nice\": %.2f, \"sys\": %.2f, "
                         "\"iowait\": %.2f, \"irq\": %.2f, \"soft\": %.2f, \"steal\": %.2f, "
-                        "\"guest\": %.2f, \"gnice\": %.2f, \"idle\": %.2f}", i - 1,
+                        "\"guest\": %.2f, \"gnice\": %.2f, \"idle\": %.2f}", cpu_name,
                         (scc->cpu_user - scc->cpu_guest) < (scp->cpu_user - scp->cpu_guest) ?
                         0.0 :
                         ll_sp_value(scp->cpu_user - scp->cpu_guest,