event_id_t
next_event_id ()
{
- /* libsmf supports reading variable-length data up to 4 bytes only.
- * so we wrap around at 2^(4 * 7) - 1
- *
- * interestingly enough libsmf happily writes data longer than that, but then
- * fails to load it in ./libs/evoral/src/libsmf/smf_load.c:237
- * g_critical("SMF error: Variable Length Quantities longer than four bytes are not supported yet.");
+ /* TODO: handle 31bit overflow , event_id_t is an int32_t,
+ * and libsmf only supports loading uint32_t vlq's, see smf_extract_vlq()
*
* event-IDs only have to be unique per .mid file.
* Previously (Ardour 4.2ish) Ardour re-generated those IDs when loading the
* file but that lead to .mid files being modified on every load/save.
*
- * For now just assume that by the time 2^28 is reached, files with low ids have vanished.
- * There is only one user who managed to get to 268 million events so far.
- * quite a feat: id-counter="6483089" event-counter="276390506"
- * Eventually a proper solution will have to be implemented.
+ * current user-record: is event-counter="276390506" (just abov 2^28)
*/
- return g_atomic_int_add (&_event_id_counter, 1) & 268435455;
+ return g_atomic_int_add (&_event_id_counter, 1);
}
#ifdef EVORAL_EVENT_ALLOC
{
uint32_t val = 0;
const unsigned char *c = buf;
+ int i = 0;
- for (;;) {
+ for (;; ++i) {
if (c >= buf + buffer_length) {
g_critical("End of buffer in extract_vlq().");
return (-1);
}
+ if (i == 4 && (val & 0xfe000000)) {
+ g_critical("SMF error: Variable Length Quantities longer than four bytes are not supported yet.");
+ return (-2);
+ }
+
val = (val << 7) + (*c & 0x7F);
if (*c & 0x80)
*value = val;
*len = c - buf + 1;
- if (*len > 4) {
+ if (*len > 5) {
g_critical("SMF error: Variable Length Quantities longer than four bytes are not supported yet.");
return (-2);
}