Fix handling of empty input

robryk · robryk · commit 483c93eb07e9 · 2017-04-03T15:42:47.000+02:00
Fixes #166
diff --git a/guetzli/guetzli.cc b/guetzli/guetzli.cc
@@ -163,7 +163,7 @@ std::string ReadFileOrDie(const char* filename) {
   off_t buffer_size = 8192;
 
   if (fseek(f, 0, SEEK_END) == 0) {
-    buffer_size = ftell(f);
+    buffer_size = std::max<off_t>(ftell(f), 1);
     if (fseek(f, 0, SEEK_SET) != 0) {
       perror("fseek");
       exit(1);
diff --git a/tests/smoke_test.sh b/tests/smoke_test.sh
@@ -49,3 +49,10 @@ run_test png file stdout --nomemlimit
 run_test png file stdout --memlimit 100
 run_test png file stdout --quality 85
 
+echo $GUETZLI /dev/null /dev/null
+$GUETZLI /dev/null /dev/null
+if [[ $? -ne 1 ]]; then
+  echo "Expected a clean failure"
+  exit 1
+fi
+
