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authorMax Kellermann <max@duempel.org>2009-03-02 20:40:31 +0100
committerMax Kellermann <max@duempel.org>2009-03-02 20:40:31 +0100
commit36d24fb7eae3a7a761cb1659d10464f65ecdddf9 (patch)
tree51c8166fb9723f891a58122166077dcb7fd04db8 /src/input/curl_input_plugin.c
parent2e51365ea4b636560d234b0b937a6c8dfb528c10 (diff)
downloadmpd-36d24fb7eae3a7a761cb1659d10464f65ecdddf9.tar.gz
mpd-36d24fb7eae3a7a761cb1659d10464f65ecdddf9.tar.xz
mpd-36d24fb7eae3a7a761cb1659d10464f65ecdddf9.zip
input: moved plugins to ./src/input/
Create a sub directory for input plugins.
Diffstat (limited to 'src/input/curl_input_plugin.c')
-rw-r--r--src/input/curl_input_plugin.c958
1 files changed, 958 insertions, 0 deletions
diff --git a/src/input/curl_input_plugin.c b/src/input/curl_input_plugin.c
new file mode 100644
index 000000000..b6d444a8a
--- /dev/null
+++ b/src/input/curl_input_plugin.c
@@ -0,0 +1,958 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2008 Max Kellermann <max@duempel.org>
+ * This project's homepage is: 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 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>
+#include <sys/select.h>
+#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;
+
+void input_curl_global_init(void)
+{
+ CURLcode code = curl_global_init(CURL_GLOBAL_ALL);
+ if (code != CURLE_OK)
+ g_warning("curl_global_init() failed: %s\n",
+ curl_easy_strerror(code));
+
+ http_200_aliases = curl_slist_append(http_200_aliases, "ICY 200 OK");
+}
+
+void input_curl_global_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;
+}
+
+/**
+ * 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;
+ CURLMcode mcode = CURLM_CALL_MULTI_PERFORM;
+ 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
+
+ /* fill the buffer */
+
+ 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 0;
+ }
+
+ 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 0;
+ }
+
+ bret = input_curl_multi_info_read(is);
+ if (!bret)
+ 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;
+ }
+
+ 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 (strcasecmp(name, "accept-ranges") == 0) {
+ /* a stream with icy-metadata is not seekable */
+ if (!icy_defined(&c->icy_metadata))
+ is->seekable = true;
+ } else if (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 (strcasecmp(name, "content-type") == 0) {
+ g_free(is->mime);
+ is->mime = g_strndup(value, end - value);
+ } else if (strcasecmp(name, "icy-name") == 0 ||
+ strcasecmp(name, "ice-name") == 0 ||
+ 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 (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;
+ const char *proxy_host;
+ const char *proxy_port;
+ const char *proxy_user;
+ const char *proxy_pass;
+
+ 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);
+
+ proxy_host = config_get_string(CONF_HTTP_PROXY_HOST, NULL);
+ proxy_port = config_get_string(CONF_HTTP_PROXY_PORT, NULL);
+
+ if (proxy_host != NULL) {
+ char *proxy_host_str;
+
+ if (proxy_port == NULL) {
+ proxy_host_str = g_strdup(proxy_host);
+ } else {
+ proxy_host_str =
+ g_strconcat(proxy_host, ":", proxy_port, NULL);
+ }
+ curl_easy_setopt(c->easy, CURLOPT_PROXY, proxy_host_str);
+ g_free(proxy_host_str);
+ }
+
+ proxy_user = config_get_string(CONF_HTTP_PROXY_USER, NULL);
+ proxy_pass = config_get_string(CONF_HTTP_PROXY_PASSWORD, NULL);
+
+ if ((proxy_user != NULL) && (proxy_pass != NULL)) {
+ char *proxy_auth_str =
+ g_strconcat(proxy_user, ":", proxy_pass, 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 = {
+ .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,
+};