kicad_curl.cpp

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2015 Mark Roszko <[email protected]>
 * Copyright (C) 2016 SoftPLC Corporation, Dick Hollenbeck <[email protected]>
 * Copyright (C) 2015-2021 KiCad Developers, see AUTHORS.txt for contributors.
 *
 * 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 3
 * 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, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
// kicad_curl.h must be included before wx headers, to avoid
// conflicts for some defines, at least on Windows
#include <kicad_curl/kicad_curl.h>
 
#include <mutex>
#include <ki_exception.h> // THROW_IO_ERROR
 
 
 
// These are even more private than class members, and since there is only
// one instance of KICAD_CURL ever, these statics are hidden here to simplify the
// client (API) header file.
static volatile bool s_initialized;
 
static std::mutex s_lock; // for s_initialized
 
static void at_terminate()
{
 KICAD_CURL::Cleanup();
}
 
 
void KICAD_CURL::Init()
{
 // We test s_initialized twice in an effort to avoid
 // unnecessarily locking s_lock. This understands that the common case
 // will not need to lock.
 if( !s_initialized )
 {
 std::lock_guard<std::mutex> lock( s_lock );
 
 if( !s_initialized )
 {
 if( curl_global_init( CURL_GLOBAL_ALL ) != CURLE_OK )
 {
 THROW_IO_ERROR( "curl_global_init() failed." );
 }
 
 s_initialized = true;
 }
 }
}
 
 
void KICAD_CURL::Cleanup()
{
 /*
 
 Calling lock_guard() from a static destructor will typically be bad, since the
 s_lock may already have been statically destroyed itself leading to a boost
 exception. (Remember C++ does not provide certain sequencing of static
 destructor invocation.)
 
 To prevent this we test s_initialized twice, which ensures that the lock_guard
 is only instantiated on the first call, which should be from
 PGM_BASE::destroy() which is first called earlier than static destruction.
 Then when called again from the actual PGM_BASE::~PGM_BASE() function,
 lock_guard will not be instantiated because s_initialized will be false.
 
 */
 
 if( s_initialized )
 {
 std::lock_guard<std::mutex> lock( s_lock );
 
 if( s_initialized )
 {
 curl_global_cleanup();
 
 atexit( &at_terminate );
 
 s_initialized = false;
 }
 }
}
 
 
std::string KICAD_CURL::GetSimpleVersion()
{
 if( !s_initialized )
 Init();
 
 curl_version_info_data* info = curl_version_info( CURLVERSION_NOW );
 
 std::string res;
 
 if( info->version )
 {
 res += "libcurl version: " + std::string( info->version );
 }
 
 res += " (";
 
 if( info->features & CURL_VERSION_SSL )
 {
 res += "with SSL - ";
 res += std::string( info->ssl_version );
 }
 else
 {
 res += "without SSL";
 }
 res += ")";
 
 return res;
}
 
 
std::string GetKicadCurlVersion()
{
 return KICAD_CURL::GetVersion();
}
 
 
std::string GetCurlLibVersion()
{
 return LIBCURL_VERSION;
}