Function buf_printf

ds4_server.c:145–157

static void buf_putc(buf *b, char c) {
    buf_append(b, &c, 1);
}

static void buf_puts(buf *b, const char *s) {
    buf_append(b, s, strlen(s));
}

static void buf_printf(buf *b, const char *fmt, ...) {
    va_list ap;
    va_start(ap, fmt);
    va_list ap2;
    va_copy(ap2, ap);
    int n = vsnprintf(NULL, 0, fmt, ap);
    va_end(ap);
    if (n < 0) die("vsnprintf failed");
    buf_reserve(b, (size_t)n);
    vsnprintf(b->ptr + b->len, b->cap - b->len, fmt, ap2);