From 4eb3e65353484c6c5cf81046d7b2296151ef3b83 Mon Sep 17 00:00:00 2001
From: nocjj <[email protected]>
Date: Sat, 19 Sep 2020 14:48:06 +0800
Subject: [PATCH 4/4] bugfix: check unsigned number flip before getting delta

Sometimes, a very large number will appear in EXTxxx display items.
The reason of this phenomenon is that we do not check the size of
two unsigned numbers before getting delta value of them,
which will cause unsigned number flip.
So add check before getting delta value.

Signed-off-by: Jiajun Chen <[email protected]>
---
 src/type.h  | 6 +++++-
 src/vmtop.c | 2 +-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/type.h b/src/type.h
index 85edc52..0e92388 100644
--- a/src/type.h
+++ b/src/type.h
@@ -42,7 +42,11 @@ typedef unsigned long long u64;
     static inline void DELTA_NAME(v)(struct domain *new, \
                                      struct domain *old) \
     {                                                    \
-        new->DELTA_VALUE(v) = new->v - old->v;           \
+        if (new->v >= old->v) {                          \
+            new->DELTA_VALUE(v) = new->v - old->v;       \
+        } else {                                         \
+            new->DELTA_VALUE(v) = old->DELTA_VALUE(v);   \
+        }                                                \
     }
 
 #define SUM_NAME(v) domain_sum_ ## v
diff --git a/src/vmtop.c b/src/vmtop.c
index 18d3010..7a1b19b 100644
--- a/src/vmtop.c
+++ b/src/vmtop.c
@@ -250,7 +250,7 @@ static void show_task(struct domain *task)
     int showd_field = 0;
     showd_task++;
     if (showd_task < begin_task ||
-        showd_task - begin_task > scr_row_size - 4) {
+        showd_task - begin_task > scr_row_size - 5) {
         return;
     }
     clrtoeol();
-- 
2.23.0