From b37147744e34c0f23acb391de6bd04a0a1dc8cca Mon Sep 17 00:00:00 2001
From: wm4 <wm4@nowhere>
Date: Fri, 21 Jun 2013 21:18:03 +0200
Subject: [PATCH] demux: add utility functions for preloading demuxers

These will be needed by subtitle demuxers, which read all data on
initialization.
---
 demux/demux.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++---
 demux/demux.h | 11 ++++++--
 2 files changed, 81 insertions(+), 5 deletions(-)

diff --git a/demux/demux.c b/demux/demux.c
index 23c4a28706..be00f38bd7 100644
--- a/demux/demux.c
+++ b/demux/demux.c
@@ -482,13 +482,16 @@ void free_demuxer(demuxer_t *demuxer)
     talloc_free(demuxer);
 }
 
-void demuxer_add_packet(demuxer_t *demuxer, struct sh_stream *stream,
-                        demux_packet_t *dp)
+// Returns the same value as demuxer->fill_buffer: 1 ok, 0 EOF/not selected.
+int demuxer_add_packet(demuxer_t *demuxer, struct sh_stream *stream,
+                       demux_packet_t *dp)
 {
-    if (!demuxer_stream_is_selected(demuxer, stream)) {
+    if (!dp || !demuxer_stream_is_selected(demuxer, stream)) {
         free_demux_packet(dp);
+        return 0;
     } else {
         ds_add_packet(demuxer->ds[stream->type], dp);
+        return 1;
     }
 }
 
@@ -1518,3 +1521,69 @@ int demuxer_set_angle(demuxer_t *demuxer, int angle)
 
     return angle;
 }
+
+static int packet_sort_compare(const void *p1, const void *p2)
+{
+    struct demux_packet *c1 = *(struct demux_packet **)p1;
+    struct demux_packet *c2 = *(struct demux_packet **)p2;
+
+    if (c1->pts > c2->pts)
+        return 1;
+    else if (c1->pts < c2->pts)
+        return -1;
+    return 0;
+}
+
+void demux_packet_list_sort(struct demux_packet **pkts, int num_pkts)
+{
+    qsort(pkts, num_pkts, sizeof(struct demux_packet *), packet_sort_compare);
+}
+
+void demux_packet_list_seek(struct demux_packet **pkts, int num_pkts,
+                            int *current, float rel_seek_secs, int flags)
+{
+    double ref_time = 0;
+    if (*current >= 0 && *current < num_pkts) {
+        ref_time = pkts[*current]->pts;
+    } else if (*current == num_pkts && num_pkts > 0) {
+        ref_time = pkts[num_pkts - 1]->pts + pkts[num_pkts - 1]->duration;
+    }
+
+    if (flags & SEEK_ABSOLUTE)
+        ref_time = 0;
+
+    if (flags & SEEK_FACTOR) {
+        ref_time += demux_packet_list_duration(pkts, num_pkts) * rel_seek_secs;
+    } else {
+        ref_time += rel_seek_secs;
+    }
+
+    // Could do binary search, but it's probably not worth the complexity.
+    int last_index = 0;
+    for (int n = 0; n < num_pkts; n++) {
+        if (pkts[n]->pts > ref_time)
+            break;
+        last_index = n;
+    }
+    *current = last_index;
+}
+
+double demux_packet_list_duration(struct demux_packet **pkts, int num_pkts)
+{
+    if (num_pkts > 0)
+        return pkts[num_pkts - 1]->pts + pkts[num_pkts - 1]->duration;
+    return 0;
+}
+
+struct demux_packet *demux_packet_list_fill(struct demux_packet **pkts,
+                                            int num_pkts, int *current)
+{
+    if (*current < 0)
+        *current = 0;
+    if (*current >= num_pkts)
+        return NULL;
+    struct demux_packet *new = talloc(NULL, struct demux_packet);
+    *new = *pkts[*current];
+    *current += 1;
+    return new;
+}
diff --git a/demux/demux.h b/demux/demux.h
index a82fbea91a..bf16001c0f 100644
--- a/demux/demux.h
+++ b/demux/demux.h
@@ -311,8 +311,8 @@ demuxer_t *new_sub_pseudo_demuxer(struct MPOpts *opts);
 
 void free_demuxer(struct demuxer *demuxer);
 
-void demuxer_add_packet(demuxer_t *demuxer, struct sh_stream *stream,
-                        demux_packet_t *dp);
+int demuxer_add_packet(demuxer_t *demuxer, struct sh_stream *stream,
+                       demux_packet_t *dp);
 void ds_add_packet(struct demux_stream *ds, struct demux_packet *dp);
 void ds_read_packet(struct demux_stream *ds, struct stream *stream, int len,
                     double pts, int64_t pos, bool keyframe);
@@ -426,4 +426,11 @@ struct sh_stream *demuxer_stream_by_demuxer_id(struct demuxer *d,
 
 bool demuxer_stream_is_selected(struct demuxer *d, struct sh_stream *stream);
 
+void demux_packet_list_sort(struct demux_packet **pkts, int num_pkts);
+void demux_packet_list_seek(struct demux_packet **pkts, int num_pkts,
+                            int *current, float rel_seek_secs, int flags);
+double demux_packet_list_duration(struct demux_packet **pkts, int num_pkts);
+struct demux_packet *demux_packet_list_fill(struct demux_packet **pkts,
+                                            int num_pkts, int *current);
+
 #endif /* MPLAYER_DEMUXER_H */