Don't atoi off the end of a buffer chunk.

Fixes bug 20894; bugfix on 0.2.0.16-alpha.

We already applied a workaround for this as 20834, so no need to
freak out (unless you didn't apply 20384 yet).

src/common/util.c

@@ -712,6 +712,19 @@ tor_strisnonupper(const char *s)
   return 1;
 }
 
+/** Return true iff every character in <b>s</b> is whitespace space; else
+ * return false. */
+int
+tor_strisspace(const char *s)
+{
+  while (*s) {
+    if (!TOR_ISSPACE(*s))
+      return 0;
+    s++;
+  }
+  return 1;
+}
+
 /** As strcmp, except that either string may be NULL.  The NULL string is
  * considered to be before any non-NULL string. */
 int

src/common/util.h

@@ -186,6 +186,7 @@ void tor_strlower(char *s) ATTR_NONNULL((1));
 void tor_strupper(char *s) ATTR_NONNULL((1));
 int tor_strisprint(const char *s) ATTR_NONNULL((1));
 int tor_strisnonupper(const char *s) ATTR_NONNULL((1));
+int tor_strisspace(const char *s);
 int strcmp_opt(const char *s1, const char *s2);
 int strcmpstart(const char *s1, const char *s2) ATTR_NONNULL((1,2));
 int strcmp_len(const char *s1, const char *s2, size_t len) ATTR_NONNULL((1,2));