Fix segfault in BarMeterMode_draw() for small terminal widths

2 files changed, 10 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index b6e19855..5643e356 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,8 @@ What's new in version 0.9.1
 * Meters update in every screen (no longer halting while on Setup, etc.)
 * BUGFIX: Support larger numbers for process times.
   (thanks to Tristan Nakagawa for the report.)
+* BUGFIX: Segfault in BarMeterMode_draw() for small terminal widths
+  (patch by Sebastian Pipping)
 
 What's new in version 0.9
 
diff --git a/Meter.c b/Meter.c
index 6947d9b3..57862364 100644
--- a/Meter.c
+++ b/Meter.c
@@ -264,13 +264,19 @@ static void BarMeterMode_draw(Meter* this, int x, int y, int w) {
    
    w--;
    x++;
-   char bar[w];
+
+   if (w < 1) {
+      attrset(CRT_colors[RESET_COLOR]);
+      return;
+   }
+   char bar[w + 1];
    
    int blockSizes[10];
    for (int i = 0; i < w; i++)
       bar[i] = ' ';
 
-   sprintf(bar + (w-strlen(buffer)), "%s", buffer);
+   const size_t barOffset = w - MIN(strlen(buffer), w);
+   snprintf(bar + barOffset, w - barOffset + 1, "%s", buffer);
 
    // First draw in the bar[] buffer...
    double total = 0.0;