client API: add stream_cb API for user-defined stream implementations

Based on #2630. Some heavy changes by committer.

Signed-off-by: wm4 <wm4@nowhere>

3 files changed, 128 insertions, 0 deletions

diff --git a/stream/stream.c b/stream/stream.c
index 846765f326..4b55b1134a 100644
--- a/stream/stream.c
+++ b/stream/stream.c
@@ -75,6 +75,7 @@ extern const stream_info_t stream_info_bdnav;
 extern const stream_info_t stream_info_rar;
 extern const stream_info_t stream_info_edl;
 extern const stream_info_t stream_info_libarchive;
+extern const stream_info_t stream_info_cb;
 
 static const stream_info_t *const stream_list[] = {
 #if HAVE_CDDA
@@ -115,6 +116,7 @@ static const stream_info_t *const stream_list[] = {
     &stream_info_edl,
     &stream_info_rar,
     &stream_info_file,
+    &stream_info_cb,
     NULL
 };
 
@@ -243,6 +245,9 @@ static stream_t *new_stream(void)
 
 static const char *match_proto(const char *url, const char *proto)
 {
+    if (strcmp(proto, "*") == 0)
+        return url;
+
     int l = strlen(proto);
     if (l > 0) {
         if (strncasecmp(url, proto, l) == 0 && strncmp("://", url + l, 3) == 0)
@@ -1111,3 +1116,17 @@ void stream_print_proto_list(struct mp_log *log)
     talloc_free(list);
     mp_info(log, "\nTotal: %d protocols\n", count);
 }
+
+bool stream_has_proto(const char *proto)
+{
+    for (int i = 0; stream_list[i]; i++) {
+        const stream_info_t *stream_info = stream_list[i];
+
+        for (int j = 0; stream_info->protocols && stream_info->protocols[j]; j++) {
+            if (strcmp(stream_info->protocols[j], proto) == 0)
+                return true;
+        }
+    }
+
+    return false;
+}
diff --git a/stream/stream.h b/stream/stream.h
index 21e497e563..1112e09f50 100644
--- a/stream/stream.h
+++ b/stream/stream.h
@@ -299,5 +299,6 @@ void mp_setup_av_network_options(struct AVDictionary **dict,
 
 void stream_print_proto_list(struct mp_log *log);
 char **stream_get_proto_list(void);
+bool stream_has_proto(const char *proto);
 
 #endif /* MPLAYER_STREAM_H */
diff --git a/stream/stream_cb.c b/stream/stream_cb.c
new file mode 100644
index 0000000000..4496e63255
--- /dev/null
+++ b/stream/stream_cb.c
@@ -0,0 +1,108 @@
+#include "config.h"
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "osdep/io.h"
+
+#include "common/common.h"
+#include "common/msg.h"
+#include "common/global.h"
+#include "stream.h"
+#include "options/m_option.h"
+#include "options/path.h"
+#include "player/client.h"
+#include "libmpv/stream_cb.h"
+
+struct priv {
+    mpv_stream_cb_info info;
+};
+
+static int fill_buffer(stream_t *s, char *buffer, int max_len)
+{
+    struct priv *p = s->priv;
+    return (int)p->info.read_fn(p->info.cookie, buffer, (size_t)max_len);
+}
+
+static int seek(stream_t *s, int64_t newpos)
+{
+    struct priv *p = s->priv;
+    return (int)p->info.seek_fn(p->info.cookie, newpos) >= 0;
+}
+
+static int control(stream_t *s, int cmd, void *arg)
+{
+    struct priv *p = s->priv;
+    switch (cmd) {
+    case STREAM_CTRL_GET_SIZE: {
+        if (!p->info.size_fn)
+            break;
+        int64_t size = p->info.size_fn(p->info.cookie);
+        if (size >= 0) {
+            *(int64_t *)arg = size;
+            return 1;
+        }
+        break;
+    }
+    }
+    return STREAM_UNSUPPORTED;
+}
+
+static void s_close(stream_t *s)
+{
+    struct priv *p = s->priv;
+    p->info.close_fn(p->info.cookie);
+}
+
+static int open_cb(stream_t *stream)
+{
+    struct priv *p = talloc_ptrtype(stream, p);
+    stream->priv = p;
+
+    bstr bproto = mp_split_proto(bstr0(stream->url), NULL);
+    char *proto = bstrto0(stream, bproto);
+
+    void *user_data;
+    mpv_stream_cb_open_ro_fn open_fn;
+
+    if (!mp_streamcb_lookup(stream->global, proto, &user_data, &open_fn))
+        return STREAM_UNSUPPORTED;
+
+    mpv_stream_cb_info info = {0};
+
+    int r = open_fn(user_data, stream->url, &info);
+    if (r < 0) {
+        if (r != MPV_ERROR_LOADING_FAILED)
+            MP_WARN(stream, "unknown error from user callback\n");
+        return STREAM_ERROR;
+    }
+
+    if (!info.read_fn || !info.close_fn) {
+        MP_FATAL(stream, "required read_fn or close_fn callbacks not set.\n");
+        return STREAM_ERROR;
+    }
+
+    p->info = info;
+
+    if (p->info.seek_fn && p->info.seek_fn(p->info.cookie, 0) >= 0) {
+        stream->seek = seek;
+        stream->seekable = true;
+    }
+    stream->fast_skip = true;
+    stream->fill_buffer = fill_buffer;
+    stream->control = control;
+    stream->read_chunk = 64 * 1024;
+    stream->close = s_close;
+
+    return STREAM_OK;
+}
+
+const stream_info_t stream_info_cb = {
+    .name = "stream_callback",
+    .open = open_cb,
+    .protocols = (const char*const[]){ "*", NULL },
+};