• Max Kellermann's avatar
    input/curl: fixed endless loop during buffering · 6037beab
    Max Kellermann authored
    When the connection is lost while buffering, the CURL input plugin may
    enter an endless loop, because it does not check the EOF condition.
    This patch makes fill_buffer() return success only if there's at least
    one buffer, which is enough of a check.x
    6037beab
curl_input_plugin.c 21.2 KB
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/*
 * Copyright (C) 2003-2009 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "input/curl_input_plugin.h"
#include "input_plugin.h"
#include "conf.h"
#include "config.h"
#include "tag.h"
#include "icy_metadata.h"

#include <assert.h>

#if defined(WIN32)
	#include <winsock2.h>
#else
	#include <sys/select.h>
#endif

#include <string.h>
#include <errno.h>

#include <curl/curl.h>
#include <glib.h>

#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().
 */
struct buffer {
	/** size of the payload */
	size_t size;

	/** how much has been consumed yet? */
	size_t consumed;

	/** the payload */
	unsigned char data[sizeof(long)];
};

struct input_curl {
	/* some buffers which were passed to libcurl, which we have
	   too free */
	char *url, *range;
	struct curl_slist *request_headers;

	/** the curl handles */
	CURL *easy;
	CURLM *multi;

	/** list of buffers, where input_curl_writefunction() appends
	    to, and input_curl_read() reads from them */
	GQueue *buffers;

	/** has something been added to the buffers list? */
	bool buffered;

	/** 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];

	/** parser for icy-metadata */
	struct icy_metadata icy_metadata;

	/** the stream name from the icy-name response header */
	char *meta_name;

	/** the tag object ready to be requested via
	    input_stream_tag() */
	struct tag *tag;
};

/** libcurl should accept "ICY 200 OK" */
static struct curl_slist *http_200_aliases;

/** HTTP proxy settings */
static const char *proxy, *proxy_user, *proxy_password;
static unsigned proxy_port;

static bool
input_curl_init(const struct config_param *param)
{
	CURLcode code = curl_global_init(CURL_GLOBAL_ALL);
	if (code != CURLE_OK) {
		g_warning("curl_global_init() failed: %s\n",
			  curl_easy_strerror(code));
		return false;
	}

	http_200_aliases = curl_slist_append(http_200_aliases, "ICY 200 OK");

	proxy = config_get_block_string(param, "proxy", NULL);
	proxy_port = config_get_block_unsigned(param, "proxy_port", 0);
	proxy_user = config_get_block_string(param, "proxy_user", NULL);
	proxy_password = config_get_block_string(param, "proxy_password",
						 NULL);

	if (proxy == NULL) {
		/* deprecated proxy configuration */
		proxy = config_get_string(CONF_HTTP_PROXY_HOST, NULL);
		proxy_port = config_get_positive(CONF_HTTP_PROXY_PORT, 0);
		proxy_user = config_get_string(CONF_HTTP_PROXY_USER, NULL);
		proxy_password = config_get_string(CONF_HTTP_PROXY_PASSWORD,
						   "");
	}

	return true;
}

static void
input_curl_finish(void)
{
	curl_slist_free_all(http_200_aliases);

	curl_global_cleanup();
}

static void
buffer_free_callback(gpointer data, G_GNUC_UNUSED gpointer user_data)
{
	struct buffer *buffer = data;

	assert(buffer->consumed <= buffer->size);

	g_free(data);
}

/* g_queue_clear() was introduced in GLib 2.14 */
#if !GLIB_CHECK_VERSION(2,14,0)
#define g_queue_clear(q) do { g_queue_free(q); q = g_queue_new(); } while (0)
#endif

/**
 * Frees the current "libcurl easy" handle, and everything associated
 * with it.
 */
static void
input_curl_easy_free(struct input_curl *c)
{
	if (c->easy != NULL) {
		curl_multi_remove_handle(c->multi, c->easy);
		curl_easy_cleanup(c->easy);
		c->easy = NULL;
	}

	curl_slist_free_all(c->request_headers);
	c->request_headers = NULL;

	g_free(c->range);
	c->range = NULL;

	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);
	}
}

/**
 * Frees this stream (but not the input_stream struct itself).
 */
static void
input_curl_free(struct input_stream *is)
{
	struct input_curl *c = is->data;

	if (c->tag != NULL)
		tag_free(c->tag);
	g_free(c->meta_name);

	input_curl_easy_free(c);

	if (c->multi != NULL)
		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);
}

static struct tag *
input_curl_tag(struct input_stream *is)
{
	struct input_curl *c = is->data;
	struct tag *tag = c->tag;

	c->tag = NULL;
	return tag;
}

static bool
input_curl_multi_info_read(struct input_stream *is)
{
	struct input_curl *c = is->data;
	CURLMsg *msg;
	int msgs_in_queue;

	while ((msg = curl_multi_info_read(c->multi,
					   &msgs_in_queue)) != NULL) {
		if (msg->msg == CURLMSG_DONE) {
			c->eof = true;
			is->ready = true;

			if (msg->data.result != CURLE_OK) {
				g_warning("curl failed: %s\n", c->error);
				is->error = -1;
				return false;
			}
		}
	}

	return true;
}

/**
 * Wait for the libcurl socket.
 *
 * @return -1 on error, 0 if no data is available yet, 1 if data is
 * available
 */
static int
input_curl_select(struct input_curl *c)
{
	fd_set rfds, wfds, efds;
	int max_fd, ret;
	CURLMcode mcode;
	/* XXX hard coded timeout value.. */
	struct timeval timeout = {
		.tv_sec = 1,
		.tv_usec = 0,
	};

	assert(!c->eof);

	FD_ZERO(&rfds);
	FD_ZERO(&wfds);
	FD_ZERO(&efds);

	mcode = curl_multi_fdset(c->multi, &rfds, &wfds, &efds, &max_fd);
	if (mcode != CURLM_OK) {
		g_warning("curl_multi_fdset() failed: %s\n",
			  curl_multi_strerror(mcode));
		return -1;
	}

	assert(max_fd >= 0);

	ret = select(max_fd + 1, &rfds, &wfds, &efds, &timeout);
	if (ret < 0)
		g_warning("select() failed: %s\n", strerror(errno));

	return ret;
}

static bool
fill_buffer(struct input_stream *is)
{
	struct input_curl *c = is->data;
	CURLMcode mcode = CURLM_CALL_MULTI_PERFORM;

	while (!c->eof && g_queue_is_empty(c->buffers)) {
		int running_handles;
		bool bret;

		if (mcode != CURLM_CALL_MULTI_PERFORM) {
			/* if we're still here, there is no input yet
			   - wait for input */
			int ret = input_curl_select(c);
			if (ret <= 0)
				/* no data yet or error */
				return false;
		}

		mcode = curl_multi_perform(c->multi, &running_handles);
		if (mcode != CURLM_OK && mcode != CURLM_CALL_MULTI_PERFORM) {
			g_warning("curl_multi_perform() failed: %s\n",
				  curl_multi_strerror(mcode));
			c->eof = true;
			is->ready = true;
			return false;
		}

		bret = input_curl_multi_info_read(is);
		if (!bret)
			return false;
	}

	return !g_queue_is_empty(c->buffers);
}

/**
 * Mark a part of the buffer object as consumed.
 */
static struct buffer *
consume_buffer(struct buffer *buffer, size_t length, GQueue *rewind_buffers)
{
	assert(buffer != NULL);
	assert(buffer->consumed < buffer->size);

	buffer->consumed += length;
	if (buffer->consumed < buffer->size)
		return buffer;

	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);

	return NULL;
}

static size_t
read_from_buffer(struct icy_metadata *icy_metadata, GQueue *buffers,
		 void *dest0, size_t length,
		 GQueue *rewind_buffers)
{
	struct buffer *buffer = g_queue_pop_head(buffers);
	uint8_t *dest = dest0;
	size_t nbytes = 0;

	assert(buffer->size > 0);
	assert(buffer->consumed < buffer->size);

	if (length > buffer->size - buffer->consumed)
		length = buffer->size - buffer->consumed;

	while (true) {
		size_t chunk;

		chunk = icy_data(icy_metadata, length);
		if (chunk > 0) {
			memcpy(dest, buffer->data + buffer->consumed,
			       chunk);
			buffer = consume_buffer(buffer, chunk, rewind_buffers);

			nbytes += chunk;
			dest += chunk;
			length -= chunk;

			if (length == 0)
				break;

			assert(buffer != NULL);
		}

		chunk = icy_meta(icy_metadata, buffer->data + buffer->consumed,
				 length);
		if (chunk > 0) {
			buffer = consume_buffer(buffer, chunk, rewind_buffers);

			length -= chunk;

			if (length == 0)
				break;

			assert(buffer != NULL);
		}
	}

	if (buffer != NULL)
		g_queue_push_head(buffers, buffer);

	return nbytes;
}

static void
copy_icy_tag(struct input_curl *c)
{
	struct tag *tag = icy_tag(&c->icy_metadata);

	if (tag == NULL)
		return;

	if (c->tag != NULL)
		tag_free(c->tag);

	if (c->meta_name != NULL && !tag_has_type(tag, TAG_ITEM_NAME))
		tag_add_item(tag, TAG_ITEM_NAME, c->meta_name);

	c->tag = tag;
}

static size_t
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 */

		success = fill_buffer(is);
		if (!success)
			return 0;

		/* 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);

			nbytes += copy;
			size -= copy;
		}
	} while (nbytes == 0);

	if (icy_defined(&c->icy_metadata))
		copy_icy_tag(c);

	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;
}

static void
input_curl_close(struct input_stream *is)
{
	input_curl_free(is);
}

static bool
input_curl_eof(G_GNUC_UNUSED struct input_stream *is)
{
	struct input_curl *c = is->data;

	return c->eof && g_queue_is_empty(c->buffers);
}

static int
input_curl_buffer(struct input_stream *is)
{
	struct input_curl *c = is->data;
	CURLMcode mcode;
	int running_handles;
	bool ret;

	c->buffered = false;

	if (!is->ready && !c->eof)
		/* not ready yet means the caller is waiting in a busy
		   loop; relax that by calling select() on the
		   socket */
		input_curl_select(c);

	do {
		mcode = curl_multi_perform(c->multi, &running_handles);
	} while (mcode == CURLM_CALL_MULTI_PERFORM &&
		 g_queue_is_empty(c->buffers));

	if (mcode != CURLM_OK && mcode != CURLM_CALL_MULTI_PERFORM) {
		g_warning("curl_multi_perform() failed: %s\n",
			  curl_multi_strerror(mcode));
		c->eof = true;
		is->ready = true;
		return -1;
	}

	ret = input_curl_multi_info_read(is);
	if (!ret)
		return -1;

	return c->buffered;
}

/** called by curl when new data is available */
static size_t
input_curl_headerfunction(void *ptr, size_t size, size_t nmemb, void *stream)
{
	struct input_stream *is = stream;
	struct input_curl *c = is->data;
	const char *header = ptr, *end, *value;
	char name[64];

	size *= nmemb;
	end = header + size;

	value = memchr(header, ':', size);
	if (value == NULL || (size_t)(value - header) >= sizeof(name))
		return size;

	memcpy(name, header, value - header);
	name[value - header] = 0;

	/* skip the colon */

	++value;

	/* strip the value */

	while (value < end && g_ascii_isspace(*value))
		++value;

	while (end > value && g_ascii_isspace(end[-1]))
		--end;

	if (g_ascii_strcasecmp(name, "accept-ranges") == 0) {
		/* a stream with icy-metadata is not seekable */
		if (!icy_defined(&c->icy_metadata))
			is->seekable = true;
	} else if (g_ascii_strcasecmp(name, "content-length") == 0) {
		char buffer[64];

		if ((size_t)(end - header) >= sizeof(buffer))
			return size;

		memcpy(buffer, value, end - value);
		buffer[end - value] = 0;

		is->size = is->offset + g_ascii_strtoull(buffer, NULL, 10);
	} else if (g_ascii_strcasecmp(name, "content-type") == 0) {
		g_free(is->mime);
		is->mime = g_strndup(value, end - value);
	} else if (g_ascii_strcasecmp(name, "icy-name") == 0 ||
		   g_ascii_strcasecmp(name, "ice-name") == 0 ||
		   g_ascii_strcasecmp(name, "x-audiocast-name") == 0) {
		g_free(c->meta_name);
		c->meta_name = g_strndup(value, end - value);

		if (c->tag != NULL)
			tag_free(c->tag);

		c->tag = tag_new();
		tag_add_item(c->tag, TAG_ITEM_NAME, c->meta_name);
	} else if (g_ascii_strcasecmp(name, "icy-metaint") == 0) {
		char buffer[64];
		size_t icy_metaint;

		if ((size_t)(end - header) >= sizeof(buffer) ||
		    icy_defined(&c->icy_metadata))
			return size;

		memcpy(buffer, value, end - value);
		buffer[end - value] = 0;

		icy_metaint = g_ascii_strtoull(buffer, NULL, 10);
		g_debug("icy-metaint=%zu", icy_metaint);

		if (icy_metaint > 0) {
			icy_start(&c->icy_metadata, icy_metaint);

			/* 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;
			}
		}
	}

	return size;
}

/** called by curl when new data is available */
static size_t
input_curl_writefunction(void *ptr, size_t size, size_t nmemb, void *stream)
{
	struct input_stream *is = stream;
	struct input_curl *c = is->data;
	struct buffer *buffer;

	size *= nmemb;
	if (size == 0)
		return 0;

	buffer = g_malloc(sizeof(*buffer) - sizeof(buffer->data) + size);
	buffer->size = size;
	buffer->consumed = 0;
	memcpy(buffer->data, ptr, size);
	g_queue_push_tail(c->buffers, buffer);

	c->buffered = true;
	is->ready = true;

	return size;
}

static bool
input_curl_easy_init(struct input_stream *is)
{
	struct input_curl *c = is->data;
	CURLcode code;
	CURLMcode mcode;

	c->eof = false;

	c->easy = curl_easy_init();
	if (c->easy == NULL) {
		g_warning("curl_easy_init() failed\n");
		return false;
	}

	mcode = curl_multi_add_handle(c->multi, c->easy);
	if (mcode != CURLM_OK)
		return false;

	curl_easy_setopt(c->easy, CURLOPT_USERAGENT,
			 "Music Player Daemon " VERSION);
	curl_easy_setopt(c->easy, CURLOPT_HEADERFUNCTION,
			 input_curl_headerfunction);
	curl_easy_setopt(c->easy, CURLOPT_WRITEHEADER, is);
	curl_easy_setopt(c->easy, CURLOPT_WRITEFUNCTION,
			 input_curl_writefunction);
	curl_easy_setopt(c->easy, CURLOPT_WRITEDATA, is);
	curl_easy_setopt(c->easy, CURLOPT_HTTP200ALIASES, http_200_aliases);
	curl_easy_setopt(c->easy, CURLOPT_FOLLOWLOCATION, 1);
	curl_easy_setopt(c->easy, CURLOPT_MAXREDIRS, 5);
	curl_easy_setopt(c->easy, CURLOPT_FAILONERROR, true);
	curl_easy_setopt(c->easy, CURLOPT_ERRORBUFFER, c->error);

	if (proxy != NULL)
		curl_easy_setopt(c->easy, CURLOPT_PROXY, proxy);

	if (proxy_port > 0)
		curl_easy_setopt(c->easy, CURLOPT_PROXYPORT, (long)proxy_port);

	if (proxy_user != NULL && proxy_password != NULL) {
		char *proxy_auth_str =
			g_strconcat(proxy_user, ":", proxy_password, NULL);
		curl_easy_setopt(c->easy, CURLOPT_PROXYUSERPWD, proxy_auth_str);
		g_free(proxy_auth_str);
	}

	code = curl_easy_setopt(c->easy, CURLOPT_URL, c->url);
	if (code != CURLE_OK)
		return false;

	c->request_headers = NULL;
	c->request_headers = curl_slist_append(c->request_headers,
					       "Icy-Metadata: 1");
	curl_easy_setopt(c->easy, CURLOPT_HTTPHEADER, c->request_headers);

	return true;
}

static bool
input_curl_send_request(struct input_curl *c)
{
	CURLMcode mcode;
	int running_handles;

	do {
		mcode = curl_multi_perform(c->multi, &running_handles);
	} while (mcode == CURLM_CALL_MULTI_PERFORM);

	if (mcode != CURLM_OK) {
		g_warning("curl_multi_perform() failed: %s\n",
			  curl_multi_strerror(mcode));
		return false;
	}

	return true;
}

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;
	bool ret;

	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 (!is->seekable)
		return false;

	/* calculate the absolute offset */

	switch (whence) {
	case SEEK_SET:
		break;

	case SEEK_CUR:
		offset += is->offset;
		break;

	case SEEK_END:
		if (is->size < 0)
			/* stream size is not known */
			return false;

		offset += is->size;
		break;

	default:
		return false;
	}

	if (offset < 0)
		return false;

	/* 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);
		if (buffer != NULL)
			g_queue_push_head(c->buffers, buffer);

		is->offset += length;
	}

	if (offset == is->offset)
		return true;

	/* close the old connection and open a new one */

	input_curl_easy_free(c);

	is->offset = offset;
	if (is->offset == is->size) {
		/* seek to EOF: simulate empty result; avoid
		   triggering a "416 Requested Range Not Satisfiable"
		   response */
		c->eof = true;
		return true;
	}

	ret = input_curl_easy_init(is);
	if (!ret)
		return false;

	/* send the "Range" header */

	if (is->offset > 0) {
		c->range = g_strdup_printf("%lld-", (long long)is->offset);
		curl_easy_setopt(c->easy, CURLOPT_RANGE, c->range);
	}

	ret = input_curl_send_request(c);
	if (!ret)
		return false;

	return input_curl_multi_info_read(is);
}

static bool
input_curl_open(struct input_stream *is, const char *url)
{
	struct input_curl *c;
	bool ret;

	if (strncmp(url, "http://", 7) != 0)
		return false;

	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;

	c->multi = curl_multi_init();
	if (c->multi == NULL) {
		g_warning("curl_multi_init() failed\n");

		input_curl_free(is);
		return false;
	}

	icy_clear(&c->icy_metadata);
	c->tag = NULL;

	ret = input_curl_easy_init(is);
	if (!ret) {
		input_curl_free(is);
		return false;
	}

	ret = input_curl_send_request(c);
	if (!ret) {
		input_curl_free(is);
		return false;
	}

	ret = input_curl_multi_info_read(is);
	if (!ret) {
		input_curl_free(is);
		return false;
	}

	return true;
}

const struct input_plugin input_plugin_curl = {
	.name = "curl",
	.init = input_curl_init,
	.finish = input_curl_finish,

	.open = input_curl_open,
	.close = input_curl_close,
	.tag = input_curl_tag,
	.buffer = input_curl_buffer,
	.read = input_curl_read,
	.eof = input_curl_eof,
	.seek = input_curl_seek,
};