transmission/gtk/FaviconCache.cc

144 lines
3.8 KiB
C++

// This file Copyright © 2012-2022 Mnemosyne LLC.
// It may be used under GPLv2 (SPDX: GPL-2.0-only), GPLv3 (SPDX: GPL-3.0-only),
// or any future license endorsed by Mnemosyne LLC.
// License text can be found in the licenses/ folder.
#include <array>
#include <memory>
#include <string>
#include <glib/gstdio.h> /* g_remove() */
#include <libtransmission/transmission.h>
#include <libtransmission/web.h> // tr_sessionFetch()
#include <libtransmission/web-utils.h>
#include "FaviconCache.h"
#include "Utils.h" /* gtr_get_host_from_url() */
namespace
{
std::array<char const*, 4> const image_types = { "ico", "png", "gif", "jpg" };
struct favicon_data
{
tr_session* session = nullptr;
std::function<void(Glib::RefPtr<Gdk::Pixbuf> const&)> func;
std::string host;
std::string contents;
size_t type = 0;
};
Glib::ustring get_url(std::string const& host, size_t image_type)
{
return gtr_sprintf("http://%s/favicon.%s", host, image_types[image_type]);
}
std::string favicon_get_cache_dir()
{
static std::string dir;
if (dir.empty())
{
dir = Glib::build_filename(Glib::get_user_cache_dir(), "transmission", "favicons");
(void)g_mkdir_with_parents(dir.c_str(), 0777);
}
return dir;
}
std::string favicon_get_cache_filename(std::string const& host)
{
return Glib::build_filename(favicon_get_cache_dir(), host);
}
void favicon_save_to_cache(std::string const& host, std::string const& data)
{
Glib::file_set_contents(favicon_get_cache_filename(host), data);
}
Glib::RefPtr<Gdk::Pixbuf> favicon_load_from_cache(std::string const& host)
{
auto const filename = favicon_get_cache_filename(host);
try
{
return Gdk::Pixbuf::create_from_file(filename, 16, 16, false);
}
catch (Glib::Error const&)
{
g_remove(filename.c_str());
return {};
}
}
void favicon_web_done_cb(tr_web::FetchResponse const& response);
bool favicon_web_done_idle_cb(std::unique_ptr<favicon_data> fav)
{
Glib::RefPtr<Gdk::Pixbuf> pixbuf;
if (!fav->contents.empty()) /* we got something... try to make a pixbuf from it */
{
favicon_save_to_cache(fav->host, fav->contents);
pixbuf = favicon_load_from_cache(fav->host);
}
if (pixbuf == nullptr && ++fav->type < image_types.size()) /* keep trying */
{
fav->contents.clear();
auto* const session = fav->session;
auto const next_url = get_url(fav->host, fav->type);
tr_sessionFetch(session, { next_url.raw(), favicon_web_done_cb, fav.release() });
}
// Not released into the next web request, means we're done trying (even if `pixbuf` is still invalid)
if (fav != nullptr)
{
fav->func(pixbuf);
}
return false;
}
void favicon_web_done_cb(tr_web::FetchResponse const& response)
{
auto* const fav = static_cast<favicon_data*>(response.user_data);
fav->contents = response.body;
Glib::signal_idle().connect([fav]() { return favicon_web_done_idle_cb(std::unique_ptr<favicon_data>(fav)); });
}
} // namespace
void gtr_get_favicon(
tr_session* session,
std::string const& host,
std::function<void(Glib::RefPtr<Gdk::Pixbuf> const&)> const& pixbuf_ready_func)
{
auto pixbuf = favicon_load_from_cache(host);
if (pixbuf != nullptr)
{
pixbuf_ready_func(pixbuf);
}
else
{
auto data = std::make_unique<favicon_data>();
data->session = session;
data->func = pixbuf_ready_func;
data->host = host;
tr_sessionFetch(session, { get_url(host, 0).raw(), favicon_web_done_cb, data.release() });
}
}
void gtr_get_favicon_from_url(
tr_session* session,
Glib::ustring const& url,
std::function<void(Glib::RefPtr<Gdk::Pixbuf> const&)> const& pixbuf_ready_func)
{
auto const host = std::string{ tr_urlParse(url.c_str())->host };
gtr_get_favicon(session, host, pixbuf_ready_func);
}