+int columns(void) {
+ static __thread int parsed_columns = 0;
+ const char *e;
+
+ if (parsed_columns > 0)
+ return parsed_columns;
+
+ if ((e = getenv("COLUMNS")))
+ parsed_columns = atoi(e);
+
+ if (parsed_columns <= 0) {
+ struct winsize ws;
+ zero(ws);
+
+ if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
+ parsed_columns = ws.ws_col;
+ }
+
+ if (parsed_columns <= 0)
+ parsed_columns = 80;
+
+ return parsed_columns;
+}
+
+int running_in_chroot(void) {
+ struct stat a, b;
+
+ zero(a);
+ zero(b);
+
+ /* Only works as root */
+
+ if (stat("/proc/1/root", &a) < 0)
+ return -errno;
+
+ if (stat("/", &b) < 0)
+ return -errno;
+
+ return
+ a.st_dev != b.st_dev ||
+ a.st_ino != b.st_ino;
+}
+
+char *ellipsize(const char *s, unsigned length, unsigned percent) {
+ size_t l, x;
+ char *r;
+
+ assert(s);
+ assert(percent <= 100);
+ assert(length >= 3);
+
+ l = strlen(s);
+
+ if (l <= 3 || l <= length)
+ return strdup(s);
+
+ if (!(r = new0(char, length+1)))
+ return r;
+
+ x = (length * percent) / 100;
+
+ if (x > length - 3)
+ x = length - 3;
+
+ memcpy(r, s, x);
+ r[x] = '.';
+ r[x+1] = '.';
+ r[x+2] = '.';
+ memcpy(r + x + 3,
+ s + l - (length - x - 3),
+ length - x - 3);
+
+ return r;
+}
+