input/curl: removed the built-in rewinding code

This has been reimplemented in the "rewind" input plugin.

1 files changed, 10 insertions, 181 deletions

diff --git a/src/input/curl_input_plugin.c b/src/input/curl_input_plugin.c
index 37d721d58..43010c8bb 100644
--- a/src/input/curl_input_plugin.c
+++ b/src/input/curl_input_plugin.c
@@ -41,9 +41,6 @@
 #undef G_LOG_DOMAIN
 #define G_LOG_DOMAIN "input_curl"
 
-/** rewinding is possible after up to 64 kB */
-static const off_t max_rewind_size = 64 * 1024;
-
 /**
  * Buffers created by input_curl_writefunction().
  */
@@ -78,9 +75,6 @@ struct input_curl {
 	/** did libcurl tell us the we're at the end of the response body? */
 	bool eof;
 
-	/** limited list of old buffers, for rewinding */
-	GQueue *rewind;
-
 	/** error message provided by libcurl */
 	char error[CURL_ERROR_SIZE];
 
@@ -176,11 +170,6 @@ input_curl_easy_free(struct input_curl *c)
 
 	g_queue_foreach(c->buffers, buffer_free_callback, NULL);
 	g_queue_clear(c->buffers);
-
-	if (c->rewind != NULL) {
-		g_queue_foreach(c->rewind, buffer_free_callback, NULL);
-		g_queue_clear(c->rewind);
-	}
 }
 
 /**
@@ -201,8 +190,6 @@ input_curl_free(struct input_stream *is)
 		curl_multi_cleanup(c->multi);
 
 	g_queue_free(c->buffers);
-	if (c->rewind != NULL)
-		g_queue_free(c->rewind);
 
 	g_free(c->url);
 	g_free(c);
@@ -322,7 +309,7 @@ fill_buffer(struct input_stream *is)
  * Mark a part of the buffer object as consumed.
  */
 static struct buffer *
-consume_buffer(struct buffer *buffer, size_t length, GQueue *rewind_buffers)
+consume_buffer(struct buffer *buffer, size_t length)
 {
 	assert(buffer != NULL);
 	assert(buffer->consumed < buffer->size);
@@ -333,19 +320,14 @@ consume_buffer(struct buffer *buffer, size_t length, GQueue *rewind_buffers)
 
 	assert(buffer->consumed == buffer->size);
 
-	if (rewind_buffers != NULL)
-		/* append this buffer to the rewind buffer list */
-		g_queue_push_tail(rewind_buffers, buffer);
-	else
-		g_free(buffer);
+	g_free(buffer);
 
 	return NULL;
 }
 
 static size_t
 read_from_buffer(struct icy_metadata *icy_metadata, GQueue *buffers,
-		 void *dest0, size_t length,
-		 GQueue *rewind_buffers)
+		 void *dest0, size_t length)
 {
 	struct buffer *buffer = g_queue_pop_head(buffers);
 	uint8_t *dest = dest0;
@@ -364,7 +346,7 @@ read_from_buffer(struct icy_metadata *icy_metadata, GQueue *buffers,
 		if (chunk > 0) {
 			memcpy(dest, buffer->data + buffer->consumed,
 			       chunk);
-			buffer = consume_buffer(buffer, chunk, rewind_buffers);
+			buffer = consume_buffer(buffer, chunk);
 
 			nbytes += chunk;
 			dest += chunk;
@@ -379,7 +361,7 @@ read_from_buffer(struct icy_metadata *icy_metadata, GQueue *buffers,
 		chunk = icy_meta(icy_metadata, buffer->data + buffer->consumed,
 				 length);
 		if (chunk > 0) {
-			buffer = consume_buffer(buffer, chunk, rewind_buffers);
+			buffer = consume_buffer(buffer, chunk);
 
 			length -= chunk;
 
@@ -418,31 +400,9 @@ input_curl_read(struct input_stream *is, void *ptr, size_t size)
 {
 	struct input_curl *c = is->data;
 	bool success;
-	GQueue *rewind_buffers;
 	size_t nbytes = 0;
 	char *dest = ptr;
 
-#ifndef NDEBUG
-	if (c->rewind != NULL &&
-	    (!g_queue_is_empty(c->rewind) || is->offset == 0)) {
-		off_t offset = 0;
-		struct buffer *buffer;
-
-		for (GList *list = g_queue_peek_head_link(c->rewind);
-		     list != NULL; list = g_list_next(list)) {
-			buffer = list->data;
-			offset += buffer->consumed;
-			assert(offset <= is->offset);
-		}
-
-		buffer = g_queue_peek_head(c->buffers);
-		if (buffer != NULL)
-			offset += buffer->consumed;
-
-		assert(offset == is->offset);
-	}
-#endif
-
 	do {
 		/* fill the buffer */
 
@@ -452,19 +412,9 @@ input_curl_read(struct input_stream *is, void *ptr, size_t size)
 
 		/* send buffer contents */
 
-		if (c->rewind != NULL &&
-		    (!g_queue_is_empty(c->rewind) || is->offset == 0))
-			/* at the beginning or already writing the rewind
-			   buffer list */
-			rewind_buffers = c->rewind;
-		else
-			/* we don't need the rewind buffers anymore */
-			rewind_buffers = NULL;
-
 		while (size > 0 && !g_queue_is_empty(c->buffers)) {
 			size_t copy = read_from_buffer(&c->icy_metadata, c->buffers,
-						       dest + nbytes, size,
-						       rewind_buffers);
+						       dest + nbytes, size);
 
 			nbytes += copy;
 			size -= copy;
@@ -476,33 +426,6 @@ input_curl_read(struct input_stream *is, void *ptr, size_t size)
 
 	is->offset += (off_t)nbytes;
 
-#ifndef NDEBUG
-	if (rewind_buffers != NULL) {
-		off_t offset = 0;
-		struct buffer *buffer;
-
-		for (GList *list = g_queue_peek_head_link(c->rewind);
-		     list != NULL; list = g_list_next(list)) {
-			buffer = list->data;
-			offset += buffer->consumed;
-			assert(offset <= is->offset);
-		}
-
-		buffer = g_queue_peek_head(c->buffers);
-		if (buffer != NULL)
-			offset += buffer->consumed;
-
-		assert(offset == is->offset);
-	}
-#endif
-
-	if (rewind_buffers != NULL && is->offset > max_rewind_size) {
-		/* drop the rewind buffer, it has grown too large */
-
-		g_queue_foreach(c->rewind, buffer_free_callback, NULL);
-		g_queue_clear(c->rewind);
-	}
-
 	return nbytes;
 }
 
@@ -635,15 +558,6 @@ input_curl_headerfunction(void *ptr, size_t size, size_t nmemb, void *stream)
 			/* a stream with icy-metadata is not
 			   seekable */
 			is->seekable = false;
-
-			if (c->rewind != NULL) {
-				/* rewinding with icy-metadata is too
-				   hairy for me .. */
-				assert(g_queue_is_empty(c->rewind));
-
-				g_queue_free(c->rewind);
-				c->rewind = NULL;
-			}
 		}
 	}
 
@@ -764,72 +678,6 @@ input_curl_send_request(struct input_curl *c)
 }
 
 static bool
-input_curl_can_rewind(struct input_stream *is)
-{
-	struct input_curl *c = is->data;
-	struct buffer *buffer;
-
-	if (c->rewind == NULL)
-		return false;
-
-	if (!g_queue_is_empty(c->rewind))
-		/* the rewind buffer hasn't been wiped yet */
-		return true;
-
-	if (g_queue_is_empty(c->buffers))
-		/* there are no buffers at all - cheap rewind not
-		   possible */
-		return false;
-
-	/* rewind is possible if this is the very first buffer of the
-	   resource */
-	buffer = (struct buffer*)g_queue_peek_head(c->buffers);
-	return (off_t)buffer->consumed == is->offset;
-}
-
-static void
-input_curl_rewind(struct input_stream *is)
-{
-	struct input_curl *c = is->data;
-#ifndef NDEBUG
-	off_t offset = 0;
-#endif
-
-	assert(c->rewind != NULL);
-
-	/* rewind the current buffer */
-
-	if (!g_queue_is_empty(c->buffers)) {
-		struct buffer *buffer =
-			(struct buffer*)g_queue_peek_head(c->buffers);
-#ifndef NDEBUG
-		offset += buffer->consumed;
-#endif
-		buffer->consumed = 0;
-	}
-
-	/* reset and move all rewind buffers back to the regular buffer list */
-
-	while (!g_queue_is_empty(c->rewind)) {
-		struct buffer *buffer =
-			(struct buffer*)g_queue_pop_tail(c->rewind);
-#ifndef NDEBUG
-		offset += buffer->consumed;
-#endif
-		buffer->consumed = 0;
-		g_queue_push_head(c->buffers, buffer);
-	}
-
-	assert(offset == is->offset);
-
-	is->offset = 0;
-
-	/* rewind the icy_metadata object */
-
-	icy_reset(&c->icy_metadata);
-}
-
-static bool
 input_curl_seek(struct input_stream *is, off_t offset, int whence)
 {
 	struct input_curl *c = is->data;
@@ -837,17 +685,9 @@ input_curl_seek(struct input_stream *is, off_t offset, int whence)
 
 	assert(is->ready);
 
-	if (whence == SEEK_SET && offset == 0) {
-		if (is->offset == 0)
-			/* no-op */
-			return true;
-
-		if (input_curl_can_rewind(is)) {
-			/* we have enough rewind buffers left */
-			input_curl_rewind(is);
-			return true;
-		}
-	}
+	if (whence == SEEK_SET && offset == is->offset)
+		/* no-op */
+		return true;
 
 	if (!is->seekable)
 		return false;
@@ -880,26 +720,16 @@ input_curl_seek(struct input_stream *is, off_t offset, int whence)
 	/* check if we can fast-forward the buffer */
 
 	while (offset > is->offset && !g_queue_is_empty(c->buffers)) {
-		GQueue *rewind_buffers;
 		struct buffer *buffer;
 		size_t length;
 
-		if (c->rewind != NULL &&
-		    (!g_queue_is_empty(c->rewind) || is->offset == 0))
-			/* at the beginning or already writing the rewind
-			   buffer list */
-			rewind_buffers = c->rewind;
-		else
-			/* we don't need the rewind buffers anymore */
-			rewind_buffers = NULL;
-
 		buffer = (struct buffer *)g_queue_pop_head(c->buffers);
 
 		length = buffer->size - buffer->consumed;
 		if (offset - is->offset < (off_t)length)
 			length = offset - is->offset;
 
-		buffer = consume_buffer(buffer, length, rewind_buffers);
+		buffer = consume_buffer(buffer, length);
 		if (buffer != NULL)
 			g_queue_push_head(c->buffers, buffer);
 
@@ -952,7 +782,6 @@ input_curl_open(struct input_stream *is, const char *url)
 	c = g_new0(struct input_curl, 1);
 	c->url = g_strdup(url);
 	c->buffers = g_queue_new();
-	c->rewind = g_queue_new();
 
 	is->plugin = &input_plugin_curl;
 	is->data = c;