transmission/gtk/FaviconCache.cc

157 lines
3.7 KiB
C++

/*
* This file Copyright (C) 2012-2021 Mnemosyne LLC
*
* It may be used under the GNU GPL versions 2 or 3
* or any future license endorsed by Mnemosyne LLC.
*
*/
#include <array>
#include <glib/gstdio.h> /* g_remove() */
#include <libtransmission/transmission.h>
#include <libtransmission/web.h> /* tr_webRun() */
#include "FaviconCache.h"
#include "Utils.h" /* gtr_get_host_from_url() */
namespace
{
std::array<char const*, 4> 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");
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_session*, bool, bool, long, std::string_view, void*);
bool favicon_web_done_idle_cb(favicon_data* fav)
{
Glib::RefPtr<Gdk::Pixbuf> pixbuf;
bool finished = false;
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);
finished = pixbuf != nullptr;
}
if (!finished) /* no pixbuf yet... */
{
if (++fav->type == image_types.size()) /* failure */
{
finished = true;
}
else /* keep trying */
{
fav->contents.clear();
tr_webRun(fav->session, get_url(fav->host, fav->type).c_str(), favicon_web_done_cb, fav);
}
}
if (finished)
{
fav->func(pixbuf);
delete fav;
}
return false;
}
void favicon_web_done_cb(
tr_session* /*session*/,
bool /*did_connect*/,
bool /*did_timeout*/,
long /*code*/,
std::string_view data,
void* vfav)
{
auto* fav = static_cast<favicon_data*>(vfav);
fav->contents.assign(std::data(data), std::size(data));
Glib::signal_idle().connect([fav]() { return favicon_web_done_idle_cb(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 = new favicon_data();
data->session = session;
data->func = pixbuf_ready_func;
data->host = host;
tr_webRun(session, get_url(host, 0).c_str(), favicon_web_done_cb, data);
}
}
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)
{
gtr_get_favicon(session, gtr_get_host_from_url(url), pixbuf_ready_func);
}