Rework the dynamic per-CPU stats code a bit. Always set 'statics->ncpus'

to the maximum number of CPUs to ensure that lcpustates[] array is always
allocated to the maximum size.  Previously, if top was started without
per-CPU stats it would allocate a smaller lcpustates[] array.  When
per-CPU stats were then enabled, it would overflow the array and trash
the cpustates_columns[] array causing the CPU stats to be printed in the
wrong locations.

Approved by:	re (kib)
MFC after:	1 week

2 files changed, 15 insertions, 3 deletions

diff --git a/contrib/top/display.c b/contrib/top/display.c
index a5a4e9e..89795c0 100644
--- a/contrib/top/display.c
+++ b/contrib/top/display.c
@@ -156,18 +156,30 @@ int display_updatecpus(statics)
 struct statics *statics;
 
 {
+    register int *lp;
     register int lines;
     register int i;
     
     /* call resize to do the dirty work */
     lines = display_resize();
-    num_cpus = statics->ncpus;
+    if (pcpu_stats)
+	num_cpus = statics->ncpus;
+    else
+	num_cpus = 1;
     cpustates_column = 5;	/* CPU: */
     if (num_cpus != 1)
     cpustates_column += 2;	/* CPU 0: */
     for (i = num_cpus; i > 9; i /= 10)
 	cpustates_column++;
 
+    /* fill the "last" array with all -1s, to insure correct updating */
+    lp = lcpustates;
+    i = num_cpustates * num_cpus;
+    while (--i >= 0)
+    {
+	*lp++ = -1;
+    }
+    
     return(lines);
 }
     
@@ -197,7 +209,7 @@ struct statics *statics;
 	num_swap = string_count(swap_names);
 	lswap = (int *)malloc(num_swap * sizeof(int));
 	num_cpustates = string_count(cpustate_names);
-	lcpustates = (int *)malloc(num_cpustates * sizeof(int) * num_cpus);
+	lcpustates = (int *)malloc(num_cpustates * sizeof(int) * statics->ncpus);
 	cpustate_columns = (int *)malloc(num_cpustates * sizeof(int));
 
 	memory_names = statics->memory_names;
diff --git a/contrib/top/top.c b/contrib/top/top.c
index 1a017a3..e7e27d5 100644
--- a/contrib/top/top.c
+++ b/contrib/top/top.c
@@ -1094,7 +1094,7 @@ restart:
 				new_message(MT_standout | MT_delayed,
 				    " Displaying %sCPU statistics.",
 				    pcpu_stats ? "per-" : "global ");
-				toggle_pcpustats(&statics);
+				toggle_pcpustats();
 				max_topn = display_updatecpus(&statics);
 				reset_display();
 				putchar('\r');