libbb: code shrink in last_char_is()

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 9 insertions, 8 deletions

diff --git a/libbb/last_char_is.c b/libbb/last_char_is.c
index 66f2e3635..918526e6c 100644
--- a/libbb/last_char_is.c
+++ b/libbb/last_char_is.c
@@ -8,16 +8,17 @@
  */
 #include "libbb.h"
 
-/* Find out if the last character of a string matches the one given.
- * Don't underrun the buffer if the string length is 0.
- */
+/* Find out if the last character of a string matches the one given */
 char* FAST_FUNC last_char_is(const char *s, int c)
 {
-        if (s && *s) {
-                size_t sz = strlen(s) - 1;
-                s += sz;
-                if ( (unsigned char)*s == c)
-                        return (char*)s;
+        if (s) {
+                size_t sz = strlen(s);
+                /* Don't underrun the buffer if the string length is 0 */
+                if (sz != 0) {
+                        s += sz - 1;
+                        if ((unsigned char)*s == c)
+                                return (char*)s;
+                }
         }
         return NULL;
 }