int snd_seq_oss_read(seq_oss_devinfo_t *dp, char __user *buf, int count) { seq_oss_readq_t *readq = dp->readq; int cnt, pos; evrec_t *q; unsigned long flags; if (readq == NULL || ! is_read_mode(dp->file_mode)) return -EIO; /* copy queued events to read buffer */ cnt = count; pos = 0; q = snd_seq_oss_readq_pick(readq, !is_nonblock_mode(dp->file_mode), &flags); if (q == NULL) return 0; do { int ev_len; /* tansfer the data */ ev_len = ev_length(q); if (copy_to_user(buf + pos, q, ev_len)) { snd_seq_oss_readq_unlock(readq, flags); break; } snd_seq_oss_readq_free(readq, flags); pos += ev_len; cnt -= ev_len; if (cnt < ev_len) break; } while ((q = snd_seq_oss_readq_pick(readq, 0, &flags)) != NULL); return count - cnt; }
int snd_seq_oss_read(struct seq_oss_devinfo *dp, char __user *buf, int count) { struct seq_oss_readq *readq = dp->readq; int result = 0, err = 0; int ev_len; union evrec rec; unsigned long flags; if (readq == NULL || ! is_read_mode(dp->file_mode)) return -ENXIO; while (count >= SHORT_EVENT_SIZE) { snd_seq_oss_readq_lock(readq, flags); err = snd_seq_oss_readq_pick(readq, &rec); if (err == -EAGAIN && !is_nonblock_mode(dp->file_mode) && result == 0) { snd_seq_oss_readq_unlock(readq, flags); snd_seq_oss_readq_wait(readq); snd_seq_oss_readq_lock(readq, flags); if (signal_pending(current)) err = -ERESTARTSYS; else err = snd_seq_oss_readq_pick(readq, &rec); } if (err < 0) { snd_seq_oss_readq_unlock(readq, flags); break; } ev_len = ev_length(&rec); if (ev_len < count) { snd_seq_oss_readq_unlock(readq, flags); break; } snd_seq_oss_readq_free(readq); snd_seq_oss_readq_unlock(readq, flags); if (copy_to_user(buf, &rec, ev_len)) { err = -EFAULT; break; } result += ev_len; buf += ev_len; count -= ev_len; } return result > 0 ? result : err; }