input_stream: non-blocking I/O

Add GMutex, GCond attributes which will be used by callers to
conditionally wait on the stream.

Remove the (now-useless) plugin method buffer(), wait on GCond
instead.  Lock the input_stream before each method call.  Do the same
with the playlist plugins.

8 files changed, 30 insertions, 36 deletions

diff --git a/src/playlist/asx_playlist_plugin.c b/src/playlist/asx_playlist_plugin.c
index b711f83f3..298687859 100644
--- a/src/playlist/asx_playlist_plugin.c
+++ b/src/playlist/asx_playlist_plugin.c
@@ -233,7 +233,8 @@ asx_open_stream(struct input_stream *is)
 					     &parser, asx_parser_destroy);
 
 	while (true) {
-		nbytes = input_stream_read(is, buffer, sizeof(buffer), &error);
+		nbytes = input_stream_lock_read(is, buffer, sizeof(buffer),
+						&error);
 		if (nbytes == 0) {
 			if (error != NULL) {
 				g_markup_parse_context_free(context);
diff --git a/src/playlist/cue_playlist_plugin.c b/src/playlist/cue_playlist_plugin.c
index e3619a284..3f2d5b34c 100644
--- a/src/playlist/cue_playlist_plugin.c
+++ b/src/playlist/cue_playlist_plugin.c
@@ -41,7 +41,8 @@ struct cue_playlist {
 };
 
 static struct playlist_provider *
-cue_playlist_open_uri(const char *uri)
+cue_playlist_open_uri(const char *uri,
+		      G_GNUC_UNUSED GMutex *mutex, G_GNUC_UNUSED GCond *cond)
 {
 	struct cue_playlist *playlist;
 	FILE *file;
diff --git a/src/playlist/despotify_playlist_plugin.c b/src/playlist/despotify_playlist_plugin.c
index 39448e01f..08a32d79d 100644
--- a/src/playlist/despotify_playlist_plugin.c
+++ b/src/playlist/despotify_playlist_plugin.c
@@ -110,7 +110,8 @@ despotify_playlist_finish(void)
 
 
 static struct playlist_provider *
-despotify_playlist_open_uri(const char *url)
+despotify_playlist_open_uri(const char *url, G_GNUC_UNUSED GMutex *mutex,
+			    G_GNUC_UNUSED GCond *cond)
 {
 	struct despotify_playlist *ctx;
 	struct despotify_session *session;
diff --git a/src/playlist/flac_playlist_plugin.c b/src/playlist/flac_playlist_plugin.c
index 8adf694ed..e20519435 100644
--- a/src/playlist/flac_playlist_plugin.c
+++ b/src/playlist/flac_playlist_plugin.c
@@ -45,7 +45,8 @@ struct flac_playlist {
 };
 
 static struct playlist_provider *
-flac_playlist_open_uri(const char *uri)
+flac_playlist_open_uri(const char *uri,
+		       G_GNUC_UNUSED GMutex *mutex, G_GNUC_UNUSED GCond *cond)
 {
 	if (!g_path_is_absolute(uri))
 		/* only local files supported */
diff --git a/src/playlist/lastfm_playlist_plugin.c b/src/playlist/lastfm_playlist_plugin.c
index 5c803cd99..86113643c 100644
--- a/src/playlist/lastfm_playlist_plugin.c
+++ b/src/playlist/lastfm_playlist_plugin.c
@@ -83,15 +83,14 @@ lastfm_finish(void)
  * @return data fetched, or NULL on error. Must be freed with g_free.
  */
 static char *
-lastfm_get(const char *url)
+lastfm_get(const char *url, GMutex *mutex, GCond *cond)
 {
 	struct input_stream *input_stream;
 	GError *error = NULL;
-	int ret;
 	char buffer[4096];
 	size_t length = 0, nbytes;
 
-	input_stream = input_stream_open(url, &error);
+	input_stream = input_stream_open(url, mutex, cond, &error);
 	if (input_stream == NULL) {
 		if (error != NULL) {
 			g_warning("%s", error->message);
@@ -101,15 +100,9 @@ lastfm_get(const char *url)
 		return NULL;
 	}
 
-	while (!input_stream->ready) {
-		ret = input_stream_buffer(input_stream, &error);
-		if (ret < 0) {
-			input_stream_close(input_stream);
-			g_warning("%s", error->message);
-			g_error_free(error);
-			return NULL;
-		}
-	}
+	g_mutex_lock(mutex);
+
+	input_stream_wait_ready(input_stream);
 
 	do {
 		nbytes = input_stream_read(input_stream, buffer + length,
@@ -124,6 +117,7 @@ lastfm_get(const char *url)
 				break;
 
 			/* I/O error */
+			g_mutex_unlock(mutex);
 			input_stream_close(input_stream);
 			return NULL;
 		}
@@ -131,6 +125,8 @@ lastfm_get(const char *url)
 		length += nbytes;
 	} while (length < sizeof(buffer));
 
+	g_mutex_unlock(mutex);
+
 	input_stream_close(input_stream);
 	return g_strndup(buffer, length);
 }
@@ -162,7 +158,7 @@ lastfm_find(const char *response, const char *name)
 }
 
 static struct playlist_provider *
-lastfm_open_uri(const char *uri)
+lastfm_open_uri(const char *uri, GMutex *mutex, GCond *cond)
 {
 	struct lastfm_playlist *playlist;
 	GError *error = NULL;
@@ -175,7 +171,7 @@ lastfm_open_uri(const char *uri)
 			"username=", lastfm_config.user, "&"
 			"passwordmd5=", lastfm_config.md5, "&"
 			"debug=0&partner=", NULL);
-	response = lastfm_get(p);
+	response = lastfm_get(p, mutex, cond);
 	g_free(p);
 	if (response == NULL)
 		return NULL;
@@ -207,7 +203,7 @@ lastfm_open_uri(const char *uri)
 				NULL);
 		g_free(escaped_uri);
 
-		response = lastfm_get(p);
+		response = lastfm_get(p, mutex, cond);
 		g_free(response);
 		g_free(p);
 
@@ -229,7 +225,7 @@ lastfm_open_uri(const char *uri)
 			NULL);
 	g_free(session);
 
-	playlist->is = input_stream_open(p, &error);
+	playlist->is = input_stream_open(p, mutex, cond, &error);
 	g_free(p);
 
 	if (playlist->is == NULL) {
@@ -243,26 +239,17 @@ lastfm_open_uri(const char *uri)
 		return NULL;
 	}
 
-	while (!playlist->is->ready) {
-		int ret = input_stream_buffer(playlist->is, &error);
-		if (ret < 0) {
-			input_stream_close(playlist->is);
-			g_free(playlist);
-			g_warning("%s", error->message);
-			g_error_free(error);
-			return NULL;
-		}
+	g_mutex_lock(mutex);
 
-		if (ret == 0)
-			/* nothing was buffered - wait */
-			g_usleep(10000);
-	}
+	input_stream_wait_ready(playlist->is);
 
 	/* last.fm does not send a MIME type, we have to fake it here
 	   :-( */
 	g_free(playlist->is->mime);
 	playlist->is->mime = g_strdup("application/xspf+xml");
 
+	g_mutex_unlock(mutex);
+
 	/* parse the XSPF playlist */
 
 	playlist->xspf = playlist_list_open_stream(playlist->is, NULL);
diff --git a/src/playlist/pls_playlist_plugin.c b/src/playlist/pls_playlist_plugin.c
index 937f02791..c4e5492af 100644
--- a/src/playlist/pls_playlist_plugin.c
+++ b/src/playlist/pls_playlist_plugin.c
@@ -115,7 +115,8 @@ pls_open_stream(struct input_stream *is)
 	GString *kf_data = g_string_new("");
 
 	do {
-		nbytes = input_stream_read(is, buffer, sizeof(buffer), &error);
+		nbytes = input_stream_lock_read(is, buffer, sizeof(buffer),
+						&error);
 		if (nbytes == 0) {
 			if (error != NULL) {
 				g_string_free(kf_data, TRUE);
diff --git a/src/playlist/rss_playlist_plugin.c b/src/playlist/rss_playlist_plugin.c
index 9ce3c6abe..6740cba7e 100644
--- a/src/playlist/rss_playlist_plugin.c
+++ b/src/playlist/rss_playlist_plugin.c
@@ -231,7 +231,8 @@ rss_open_stream(struct input_stream *is)
 					     &parser, rss_parser_destroy);
 
 	while (true) {
-		nbytes = input_stream_read(is, buffer, sizeof(buffer), &error);
+		nbytes = input_stream_lock_read(is, buffer, sizeof(buffer),
+						&error);
 		if (nbytes == 0) {
 			if (error != NULL) {
 				g_markup_parse_context_free(context);
diff --git a/src/playlist/xspf_playlist_plugin.c b/src/playlist/xspf_playlist_plugin.c
index 89a4a08a4..17d9040e2 100644
--- a/src/playlist/xspf_playlist_plugin.c
+++ b/src/playlist/xspf_playlist_plugin.c
@@ -253,7 +253,8 @@ xspf_open_stream(struct input_stream *is)
 					     &parser, xspf_parser_destroy);
 
 	while (true) {
-		nbytes = input_stream_read(is, buffer, sizeof(buffer), &error);
+		nbytes = input_stream_lock_read(is, buffer, sizeof(buffer),
+						&error);
 		if (nbytes == 0) {
 			if (error != NULL) {
 				g_markup_parse_context_free(context);