stream: redo memory streams

Make memory streams actual streams. This causes fewer weird corner cases
and actually allows using demuxers with them.

Makefile

@@ -227,6 +227,7 @@ SOURCES = talloc.c \
           stream/stream_avdevice.c \
           stream/stream_file.c \
           stream/stream_lavf.c \
+          stream/stream_memory.c \
           stream/stream_mf.c \
           stream/stream_null.c \
           stream/url.c \

stream/stream.c

@@ -78,6 +78,7 @@ extern const stream_info_t stream_info_vstream;
 extern const stream_info_t stream_info_smb;
 
 extern const stream_info_t stream_info_null;
+extern const stream_info_t stream_info_memory;
 extern const stream_info_t stream_info_mf;
 extern const stream_info_t stream_info_ffmpeg;
 extern const stream_info_t stream_info_avdevice;
@@ -130,6 +131,7 @@ static const stream_info_t *const auto_open_streams[] = {
     &stream_info_bluray,
 #endif
 
+    &stream_info_memory,
     &stream_info_null,
     &stream_info_mf,
     &stream_info_file,
@@ -725,14 +727,9 @@ int stream_check_interrupt(int time)
 stream_t *open_memory_stream(void *data, int len)
 {
     assert(len >= 0);
-    stream_t *s = new_stream(len);
-
-    s->buf_pos = 0;
-    s->buf_len = len;
-    s->start_pos = 0;
-    s->end_pos = len;
-    s->pos = len;
-    memcpy(s->buffer, data, len);
+    stream_t *s = open_stream("memory://", NULL, NULL);
+    assert(s);
+    stream_control(s, STREAM_CTRL_SET_CONTENTS, &(bstr){data, len});
     return s;
 }
 

stream/stream.h

@@ -40,6 +40,7 @@
 #define STREAMTYPE_VCD  1      // raw mode-2 CDROM reading, 2324 bytes/sector
 #define STREAMTYPE_STREAM 2    // same as FILE but no seeking (for net/stdin)
 #define STREAMTYPE_DVD  3      // libdvdread
+#define STREAMTYPE_MEMORY 4
 #define STREAMTYPE_PLAYLIST 6  // FIXME!!! same as STREAMTYPE_FILE now
 #define STREAMTYPE_CDDA 10     // raw audio CD reader
 #define STREAMTYPE_SMB 11      // smb:// url, using libsmbclient (samba)
@@ -101,6 +102,7 @@
 #define STREAM_CTRL_GET_START_TIME 20
 #define STREAM_CTRL_GET_CHAPTER_TIME 21
 #define STREAM_CTRL_GET_DVD_INFO 22
+#define STREAM_CTRL_SET_CONTENTS 23
 
 struct stream_lang_req {
     int type;     // STREAM_AUDIO, STREAM_SUB

stream/stream_memory.c

@@ -0,0 +1,84 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with mpv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <libavutil/common.h>
+
+#include "stream.h"
+
+struct priv {
+    bstr data;
+};
+
+static int fill_buffer(stream_t *s, char* buffer, int len)
+{
+    struct priv *p = s->priv;
+    bstr data = p->data;
+    if (s->pos < 0 || s->pos > data.len)
+        return 0;
+    len = FFMIN(len, data.len - s->pos);
+    memcpy(buffer, data.start + s->pos, len);
+    return len;
+}
+
+static int seek(stream_t *s, int64_t newpos)
+{
+    s->pos = newpos;
+    return 1;
+}
+
+static int control(stream_t *s, int cmd, void *arg)
+{
+    struct priv *p = s->priv;
+    switch(cmd) {
+    case STREAM_CTRL_SET_CONTENTS: ;
+        bstr *data = (bstr *)arg;
+        talloc_free(p->data.start);
+        p->data = bstrdup(s, *data);
+        s->end_pos = p->data.len;
+        return 1;
+    }
+    return STREAM_UNSUPPORTED;
+}
+
+static int open_f(stream_t *stream, int mode, void* opts, int* file_format)
+{
+    stream->type = STREAMTYPE_MEMORY;
+
+    stream->fill_buffer = fill_buffer;
+    stream->seek = seek;
+    stream->control = control;
+    stream->read_chunk = 1024 * 1024;
+
+    struct priv *p = talloc_zero(stream, struct priv);
+    stream->priv = p;
+
+    // Initial data
+    bstr data = bstr0(stream->url);
+    bstr_eatstart0(&data, "memory://");
+    stream_control(stream, STREAM_CTRL_SET_CONTENTS, &data);
+
+    return STREAM_OK;
+}
+
+const stream_info_t stream_info_memory = {
+    "Memory",
+    "memory",
+    "",
+    "",
+    open_f,
+    { "memory", NULL },
+};