filename_resolver.cpp

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2015-2020 Cirilo Bernardo <[email protected]>
 * Copyright (C) 2015-2023 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 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, 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
 */
 
#include <fstream>
#include <mutex>
#include <sstream>
 
#include <wx/log.h>
#include <wx/uri.h>
#include <pgm_base.h>
#include <trace_helpers.h>
 
#include <common.h>
#include <embedded_files.h>
#include <env_vars.h>
#include <filename_resolver.h>
#include <confirm.h>
#include <wx_filename.h>
 
// configuration file version
#define CFGFILE_VERSION 1
 
// flag bits used to track different one-off messages to users
#define ERRFLG_ALIAS (1)
#define ERRFLG_RELPATH (2)
#define ERRFLG_ENVPATH (4)
 
#define MASK_3D_RESOLVER "3D_RESOLVER"
 
static std::mutex mutex_resolver;
 
 
FILENAME_RESOLVER::FILENAME_RESOLVER() :
 m_pgm( nullptr ),
 m_project( nullptr )
{
 m_errflags = 0;
}
 
 
bool FILENAME_RESOLVER::Set3DConfigDir( const wxString& aConfigDir )
{
 if( aConfigDir.empty() )
 return false;
 
 wxFileName cfgdir( ExpandEnvVarSubstitutions( aConfigDir, m_project ), "" );
 
 cfgdir.Normalize( FN_NORMALIZE_FLAGS );
 
 if( !cfgdir.DirExists() )
 return false;
 
 m_configDir = cfgdir.GetPath();
 createPathList();
 
 return true;
}
 
 
bool FILENAME_RESOLVER::SetProject( PROJECT* aProject, bool* flgChanged )
{
 m_project = aProject;
 
 if( !aProject )
 return false;
 
 wxFileName projdir( ExpandEnvVarSubstitutions( aProject->GetProjectPath(), aProject ), "" );
 
 projdir.Normalize( FN_NORMALIZE_FLAGS );
 
 if( !projdir.DirExists() )
 return false;
 
 m_curProjDir = projdir.GetPath();
 
 if( flgChanged )
 *flgChanged = false;
 
 if( m_paths.empty() )
 {
 SEARCH_PATH al;
 al.m_Alias = wxS( "${KIPRJMOD}" );
 al.m_Pathvar = wxS( "${KIPRJMOD}" );
 al.m_Pathexp = m_curProjDir;
 m_paths.push_back( al );
 
 if( flgChanged )
 *flgChanged = true;
 }
 else
 {
 if( m_paths.front().m_Pathexp != m_curProjDir )
 {
 m_paths.front().m_Pathexp = m_curProjDir;
 
 if( flgChanged )
 *flgChanged = true;
 }
 else
 {
 return true;
 }
 }
 
#ifdef DEBUG
 {
 std::ostringstream ostr;
 ostr << __FILE__ << ": " << __FUNCTION__ << ": " << __LINE__ << "\n";
 ostr << " * [INFO] changed project dir to ";
 ostr << m_paths.front().m_Pathexp.ToUTF8();
 wxLogTrace( MASK_3D_RESOLVER, "%s\n", ostr.str().c_str() );
 }
#endif
 
 return true;
}
 
 
wxString FILENAME_RESOLVER::GetProjectDir() const
{
 return m_curProjDir;
}
 
 
void FILENAME_RESOLVER::SetProgramBase( PGM_BASE* aBase )
{
 m_pgm = aBase;
 
 if( !m_pgm || m_paths.empty() )
 return;
 
 // recreate the path list
 m_paths.clear();
 createPathList();
}
 
 
bool FILENAME_RESOLVER::createPathList()
{
 if( !m_paths.empty() )
 return true;
 
 // add an entry for the default search path; at this point
 // we cannot set a sensible default so we use an empty string.
 // the user may change this later with a call to SetProjectDir()
 
 SEARCH_PATH lpath;
 lpath.m_Alias = wxS( "${KIPRJMOD}" );
 lpath.m_Pathvar = wxS( "${KIPRJMOD}" );
 lpath.m_Pathexp = m_curProjDir;
 m_paths.push_back( lpath );
 wxFileName fndummy;
 wxUniChar psep = fndummy.GetPathSeparator();
 std::list< wxString > epaths;
 
 if( GetKicadPaths( epaths ) )
 {
 for( const wxString& currPath : epaths )
 {
 wxString currPathVarFormat = currPath;
 currPathVarFormat.Prepend( wxS( "${" ) );
 currPathVarFormat.Append( wxS( "}" ) );
 
 wxString pathVal = ExpandEnvVarSubstitutions( currPathVarFormat, m_project );
 
 if( pathVal.empty() )
 {
 lpath.m_Pathexp.clear();
 }
 else
 {
 fndummy.Assign( pathVal, "" );
 fndummy.Normalize( FN_NORMALIZE_FLAGS );
 lpath.m_Pathexp = fndummy.GetFullPath();
 }
 
 lpath.m_Alias = currPath;
 lpath.m_Pathvar = currPath;
 
 if( !lpath.m_Pathexp.empty() && psep == *lpath.m_Pathexp.rbegin() )
 lpath.m_Pathexp.erase( --lpath.m_Pathexp.end() );
 
 // we add it first with the alias set to the non-variable format
 m_paths.push_back( lpath );
 
 // now add it with the "new variable format ${VAR}"
 lpath.m_Alias = currPathVarFormat;
 m_paths.push_back( lpath );
 }
 }
 
 if( m_paths.empty() )
 return false;
 
#ifdef DEBUG
 wxLogTrace( MASK_3D_RESOLVER, wxS( " * [3D model] search paths:\n" ) );
 std::list< SEARCH_PATH >::const_iterator sPL = m_paths.begin();
 
 while( sPL != m_paths.end() )
 {
 wxLogTrace( MASK_3D_RESOLVER, wxS( " + %s : '%s'\n" ), (*sPL).m_Alias.GetData(),
 (*sPL).m_Pathexp.GetData() );
 ++sPL;
 }
#endif
 
 return true;
}
 
 
bool FILENAME_RESOLVER::UpdatePathList( const std::vector< SEARCH_PATH >& aPathList )
{
 wxUniChar envMarker( '$' );
 
 while( !m_paths.empty() && envMarker != *m_paths.back().m_Alias.rbegin() )
 m_paths.pop_back();
 
 for( const SEARCH_PATH& path : aPathList )
 addPath( path );
 
 return true;
}
 
 
wxString FILENAME_RESOLVER::ResolvePath( const wxString& aFileName, const wxString& aWorkingPath,
 const EMBEDDED_FILES* aFiles )
{
 std::lock_guard<std::mutex> lock( mutex_resolver );
 
 if( aFileName.empty() )
 return wxEmptyString;
 
 if( m_paths.empty() )
 createPathList();
 
 // first attempt to use the name as specified:
 wxString tname = aFileName;
 
 // Note: variable expansion must preferably be performed via a threadsafe wrapper for the
 // getenv() system call. If we allow the wxFileName::Normalize() routine to perform expansion
 // then we will have a race condition since wxWidgets does not assure a threadsafe wrapper
 // for getenv().
 tname = ExpandEnvVarSubstitutions( tname, m_project );
 
 // Check to see if the file is a URI for an embedded file.
 if( tname.StartsWith( FILEEXT::KiCadUriPrefix + "://" ) )
 {
 if( !aFiles )
 {
 wxLogTrace( wxT( "KICAD_EMBED" ),
 wxT( "No EMBEDDED_FILES object provided for kicad_embed URI" ) );
 return wxEmptyString;
 }
 
 wxString path = tname.Mid( 14 );
 wxFileName temp_file = aFiles->GetTemporaryFileName( path );
 
 if( !temp_file.IsOk() )
 {
 wxLogTrace( wxT( "KICAD_EMBED" ),
 wxT( "Failed to get temp file '%s' for kicad_embed URI" ), path );
 return wxEmptyString;
 }
 
 wxLogTrace( wxT( "KICAD_EMBED" ), wxT( "Opening embedded file '%s' as '%s'" ),
 tname, temp_file.GetFullPath() );
 
 return temp_file.GetFullPath();
 }
 
 wxFileName tmpFN( tname );
 
 // this case covers full paths, leading expanded vars, and paths relative to the current
 // working directory (which is not necessarily the current project directory)
 if( tmpFN.FileExists() )
 {
 tmpFN.Normalize( FN_NORMALIZE_FLAGS );
 tname = tmpFN.GetFullPath();
 
 // special case: if a path begins with ${ENV_VAR} but is not in the resolver's path list
 // then add it.
 if( aFileName.StartsWith( wxS( "${" ) ) || aFileName.StartsWith( wxS( "$(" ) ) )
 checkEnvVarPath( aFileName );
 
 return tname;
 }
 
 // if a path begins with ${ENV_VAR}/$(ENV_VAR) and is not resolved then the file either does
 // not exist or the ENV_VAR is not defined
 if( aFileName.StartsWith( "${" ) || aFileName.StartsWith( "$(" ) )
 {
 if( !( m_errflags & ERRFLG_ENVPATH ) )
 {
 m_errflags |= ERRFLG_ENVPATH;
 wxString errmsg = "[3D File Resolver] No such path; ensure the environment var is defined";
 errmsg.append( "\n" );
 errmsg.append( tname );
 errmsg.append( "\n" );
 wxLogTrace( tracePathsAndFiles, errmsg );
 }
 
 return wxEmptyString;
 }
 
 // at this point aFileName is:
 // a. an aliased shortened name or
 // b. cannot be determined
 
 // check the path relative to the current project directory;
 // NB: this is not necessarily the same as the current working directory, which has already
 // been checked. This case accounts for partial paths which do not contain ${KIPRJMOD}.
 // This check is performed before checking the path relative to ${KICAD7_3DMODEL_DIR} so that
 // users can potentially override a model within ${KICAD7_3DMODEL_DIR}.
 if( !m_paths.begin()->m_Pathexp.empty() && !tname.StartsWith( ":" ) )
 {
 tmpFN.Assign( m_paths.begin()->m_Pathexp, "" );
 wxString fullPath = tmpFN.GetPathWithSep() + tname;
 
 fullPath = ExpandEnvVarSubstitutions( fullPath, m_project );
 
 if( wxFileName::FileExists( fullPath ) )
 {
 tmpFN.Assign( fullPath );
 tmpFN.Normalize( FN_NORMALIZE_FLAGS );
 tname = tmpFN.GetFullPath();
 return tname;
 }
 
 }
 
 // check path relative to search path
 if( !aWorkingPath.IsEmpty() && !tname.StartsWith( ":" ) )
 {
 wxString tmp = aWorkingPath;
 tmp.Append( tmpFN.GetPathSeparator() );
 tmp.Append( tname );
 tmpFN.Assign( tmp );
 
 if( tmpFN.MakeAbsolute() && tmpFN.FileExists() )
 {
 tname = tmpFN.GetFullPath();
 return tname;
 }
 }
 
 // check the partial path relative to ${KICAD7_3DMODEL_DIR} (legacy behavior)
 if( !tname.StartsWith( wxS( ":" ) ) )
 {
 wxFileName fpath;
 wxString fullPath( wxString::Format( wxS( "${%s}" ),
 ENV_VAR::GetVersionedEnvVarName( wxS( "3DMODEL_DIR" ) ) ) );
 fullPath.Append( fpath.GetPathSeparator() );
 fullPath.Append( tname );
 fullPath = ExpandEnvVarSubstitutions( fullPath, m_project );
 fpath.Assign( fullPath );
 
 if( fpath.Normalize( FN_NORMALIZE_FLAGS ) && fpath.FileExists() )
 {
 tname = fpath.GetFullPath();
 return tname;
 }
 
 }
 
 // at this point the filename must contain an alias or else it is invalid
 wxString alias; // the alias portion of the short filename
 wxString relpath; // the path relative to the alias
 
 if( !SplitAlias( tname, alias, relpath ) )
 {
 if( !( m_errflags & ERRFLG_RELPATH ) )
 {
 // this can happen if the file was intended to be relative to ${KICAD7_3DMODEL_DIR}
 // but ${KICAD7_3DMODEL_DIR} is not set or is incorrect.
 m_errflags |= ERRFLG_RELPATH;
 wxString errmsg = "[3D File Resolver] No such path";
 errmsg.append( wxS( "\n" ) );
 errmsg.append( tname );
 errmsg.append( wxS( "\n" ) );
 wxLogTrace( tracePathsAndFiles, errmsg );
 }
 
 return wxEmptyString;
 }
 
 for( const SEARCH_PATH& path : m_paths )
 {
 // ${ENV_VAR} paths have already been checked; skip them
 if( path.m_Alias.StartsWith( wxS( "${" ) ) || path.m_Alias.StartsWith( wxS( "$(" ) ) )
 continue;
 
 if( path.m_Alias == alias && !path.m_Pathexp.empty() )
 {
 wxFileName fpath( wxFileName::DirName( path.m_Pathexp ) );
 wxString fullPath = fpath.GetPathWithSep() + relpath;
 
 fullPath = ExpandEnvVarSubstitutions( fullPath, m_project );
 
 if( wxFileName::FileExists( fullPath ) )
 {
 tname = fullPath;
 
 wxFileName tmp( fullPath );
 
 if( tmp.Normalize( FN_NORMALIZE_FLAGS ) )
 tname = tmp.GetFullPath();
 
 return tname;
 }
 }
 }
 
 if( !( m_errflags & ERRFLG_ALIAS ) )
 {
 m_errflags |= ERRFLG_ALIAS;
 wxString errmsg = "[3D File Resolver] No such path; ensure the path alias is defined";
 errmsg.append( "\n" );
 errmsg.append( tname.substr( 1 ) );
 errmsg.append( "\n" );
 wxLogTrace( tracePathsAndFiles, errmsg );
 }
 
 return wxEmptyString;
}
 
 
bool FILENAME_RESOLVER::addPath( const SEARCH_PATH& aPath )
{
 if( aPath.m_Alias.empty() || aPath.m_Pathvar.empty() )
 return false;
 
 std::lock_guard<std::mutex> lock( mutex_resolver );
 
 SEARCH_PATH tpath = aPath;
 
 #ifdef _WIN32
 while( tpath.m_Pathvar.EndsWith( wxT( "\\" ) ) )
 tpath.m_Pathvar.erase( tpath.m_Pathvar.length() - 1 );
 #else
 while( tpath.m_Pathvar.EndsWith( wxT( "/" ) ) && tpath.m_Pathvar.length() > 1 )
 tpath.m_Pathvar.erase( tpath.m_Pathvar.length() - 1 );
 #endif
 
 wxFileName path( ExpandEnvVarSubstitutions( tpath.m_Pathvar, m_project ), "" );
 
 path.Normalize( FN_NORMALIZE_FLAGS );
 
 if( !path.DirExists() )
 {
 wxString versionedPath = wxString::Format( wxS( "${%s}" ),
 ENV_VAR::GetVersionedEnvVarName( wxS( "3DMODEL_DIR" ) ) );
 
 if( aPath.m_Pathvar == versionedPath
 || aPath.m_Pathvar == wxS( "${KIPRJMOD}" ) || aPath.m_Pathvar == wxS( "$(KIPRJMOD)" )
 || aPath.m_Pathvar == wxS( "${KISYS3DMOD}" ) || aPath.m_Pathvar == wxS( "$(KISYS3DMOD)" ) )
 {
 // suppress the message if the missing pathvar is a system variable
 }
 else
 {
 wxString msg = _( "The given path does not exist" );
 msg.append( wxT( "\n" ) );
 msg.append( tpath.m_Pathvar );
 DisplayErrorMessage( nullptr, msg );
 }
 
 tpath.m_Pathexp.clear();
 }
 else
 {
 tpath.m_Pathexp = path.GetFullPath();
 
#ifdef _WIN32
 while( tpath.m_Pathexp.EndsWith( wxT( "\\" ) ) )
 tpath.m_Pathexp.erase( tpath.m_Pathexp.length() - 1 );
#else
 while( tpath.m_Pathexp.EndsWith( wxT( "/" ) ) && tpath.m_Pathexp.length() > 1 )
 tpath.m_Pathexp.erase( tpath.m_Pathexp.length() - 1 );
#endif
 }
 
 std::list< SEARCH_PATH >::iterator sPL = m_paths.begin();
 std::list< SEARCH_PATH >::iterator ePL = m_paths.end();
 
 while( sPL != ePL )
 {
 if( tpath.m_Alias == sPL->m_Alias )
 {
 wxString msg = _( "Alias: " );
 msg.append( tpath.m_Alias );
 msg.append( wxT( "\n" ) );
 msg.append( _( "This path:" ) + wxS( " " ) );
 msg.append( tpath.m_Pathvar );
 msg.append( wxT( "\n" ) );
 msg.append( _( "Existing path:" ) + wxS( " " ) );
 msg.append( sPL->m_Pathvar );
 DisplayErrorMessage( nullptr, _( "Bad alias (duplicate name)" ), msg );
 return false;
 }
 
 ++sPL;
 }
 
 m_paths.push_back( tpath );
 return true;
}
 
 
void FILENAME_RESOLVER::checkEnvVarPath( const wxString& aPath )
{
 bool useParen = false;
 
 if( aPath.StartsWith( wxS( "$(" ) ) )
 useParen = true;
 else if( !aPath.StartsWith( wxS( "${" ) ) )
 return;
 
 size_t pEnd;
 
 if( useParen )
 pEnd = aPath.find( wxS( ")" ) );
 else
 pEnd = aPath.find( wxS( "}" ) );
 
 if( pEnd == wxString::npos )
 return;
 
 wxString envar = aPath.substr( 0, pEnd + 1 );
 
 // check if the alias exists; if not then add it to the end of the
 // env var section of the path list
 auto sPL = m_paths.begin();
 auto ePL = m_paths.end();
 
 while( sPL != ePL )
 {
 if( sPL->m_Alias == envar )
 return;
 
 if( !sPL->m_Alias.StartsWith( wxS( "${" ) ) )
 break;
 
 ++sPL;
 }
 
 SEARCH_PATH lpath;
 lpath.m_Alias = envar;
 lpath.m_Pathvar = lpath.m_Alias;
 wxFileName tmpFN( ExpandEnvVarSubstitutions( lpath.m_Alias, m_project ), "" );
 
 wxUniChar psep = tmpFN.GetPathSeparator();
 tmpFN.Normalize( FN_NORMALIZE_FLAGS );
 
 if( !tmpFN.DirExists() )
 return;
 
 lpath.m_Pathexp = tmpFN.GetFullPath();
 
 if( !lpath.m_Pathexp.empty() && psep == *lpath.m_Pathexp.rbegin() )
 lpath.m_Pathexp.erase( --lpath.m_Pathexp.end() );
 
 if( lpath.m_Pathexp.empty() )
 return;
 
 m_paths.insert( sPL, lpath );
}
 
 
wxString FILENAME_RESOLVER::ShortenPath( const wxString& aFullPathName )
{
 wxString fname = aFullPathName;
 
 if( m_paths.empty() )
 createPathList();
 
 std::lock_guard<std::mutex> lock( mutex_resolver );
 
 std::list< SEARCH_PATH >::const_iterator sL = m_paths.begin();
 size_t idx;
 
 while( sL != m_paths.end() )
 {
 // undefined paths do not participate in the
 // file name shortening procedure
 if( sL->m_Pathexp.empty() )
 {
 ++sL;
 continue;
 }
 
 wxFileName fpath;
 
 // in the case of aliases, ensure that we use the most recent definition
 if( sL->m_Alias.StartsWith( wxS( "${" ) ) || sL->m_Alias.StartsWith( wxS( "$(" ) ) )
 {
 wxString tpath = ExpandEnvVarSubstitutions( sL->m_Alias, m_project );
 
 if( tpath.empty() )
 {
 ++sL;
 continue;
 }
 
 fpath.Assign( tpath, wxT( "" ) );
 }
 else
 {
 fpath.Assign( sL->m_Pathexp, wxT( "" ) );
 }
 
 wxString fps = fpath.GetPathWithSep();
 wxString tname;
 
 idx = fname.find( fps );
 
 if( idx == 0 )
 {
 fname = fname.substr( fps.size() );
 
 #ifdef _WIN32
 // ensure only the '/' separator is used in the internal name
 fname.Replace( wxT( "\\" ), wxT( "/" ) );
 #endif
 
 if( sL->m_Alias.StartsWith( wxS( "${" ) ) || sL->m_Alias.StartsWith( wxS( "$(" ) ) )
 {
 // old style ENV_VAR
 tname = sL->m_Alias;
 tname.Append( wxS( "/" ) );
 tname.append( fname );
 }
 else
 {
 // new style alias
 tname = "${";
 tname.append( sL->m_Alias );
 tname.append( wxS( "}/" ) );
 tname.append( fname );
 }
 
 return tname;
 }
 
 ++sL;
 }
 
#ifdef _WIN32
 // it is strange to convert an MSWin full path to use the
 // UNIX separator but this is done for consistency and can
 // be helpful even when transferring project files from
 // MSWin to *NIX.
 fname.Replace( wxT( "\\" ), wxT( "/" ) );
#endif
 
 return fname;
}
 
 
 
const std::list< SEARCH_PATH >* FILENAME_RESOLVER::GetPaths() const
{
 return &m_paths;
}
 
 
bool FILENAME_RESOLVER::SplitAlias( const wxString& aFileName,
 wxString& anAlias, wxString& aRelPath ) const
{
 anAlias.clear();
 aRelPath.clear();
 
 size_t searchStart = 0;
 
 if( aFileName.StartsWith( wxT( ":" ) ) )
 searchStart = 1;
 
 size_t tagpos = aFileName.find( wxT( ":" ), searchStart );
 
 if( tagpos == wxString::npos || tagpos == searchStart )
 return false;
 
 if( tagpos + 1 >= aFileName.length() )
 return false;
 
 anAlias = aFileName.substr( searchStart, tagpos - searchStart );
 aRelPath = aFileName.substr( tagpos + 1 );
 
 return true;
}
 
 
bool FILENAME_RESOLVER::ValidateFileName( const wxString& aFileName, bool& hasAlias ) const
{
 // Rules:
 // 1. The generic form of an aliased 3D relative path is:
 // ALIAS:relative/path
 // 2. ALIAS is a UTF string excluding wxT( "{}[]()%~<>\"='`;:.,&?/\\|$" )
 // 3. The relative path must be a valid relative path for the platform
 // 4. We allow a URI for embedded files, but only if it has a name
 
 hasAlias = false;
 
 if( aFileName.empty() )
 return false;
 
 if( aFileName.StartsWith( wxT( "file://" ) )
 || aFileName.StartsWith( FILEEXT::KiCadUriPrefix + "://" ) )
 {
 size_t prefixLength = aFileName.StartsWith( wxT( "file://" ) ) ? 7 : 14;
 if( aFileName.length() > prefixLength && aFileName[prefixLength] != '/' )
 return true;
 else
 return false;
 }
 
 wxString filename = aFileName;
 wxString lpath;
 size_t aliasStart = aFileName.StartsWith( ':' ) ? 1 : 0;
 size_t aliasEnd = aFileName.find( ':', aliasStart );
 
 // ensure that the file separators suit the current platform
#ifdef __WINDOWS__
 filename.Replace( wxT( "/" ), wxT( "\\" ) );
 
 // if we see the :\ pattern then it must be a drive designator
 if( aliasEnd != wxString::npos )
 {
 size_t pos1 = filename.find( wxT( ":\\" ) );
 
 if( pos1 != wxString::npos && ( pos1 != aliasEnd || pos1 != 1 ) )
 return false;
 
 // if we have a drive designator then we have no alias
 if( pos1 != wxString::npos )
 aliasEnd = wxString::npos;
 }
#else
 filename.Replace( wxT( "\\" ), wxT( "/" ) );
#endif
 
 // names may not end with ':'
 if( aliasEnd == aFileName.length() -1 )
 return false;
 
 if( aliasEnd != wxString::npos )
 {
 // ensure the alias component is not empty
 if( aliasEnd == aliasStart )
 return false;
 
 lpath = filename.substr( aliasStart, aliasEnd );
 
 // check the alias for restricted characters
 if( wxString::npos != lpath.find_first_of( wxT( "{}[]()%~<>\"='`;:.,&?/\\|$" ) ) )
 return false;
 
 hasAlias = true;
 lpath = aFileName.substr( aliasEnd + 1 );
 }
 else
 {
 lpath = aFileName;
 
 // in the case of ${ENV_VAR}|$(ENV_VAR)/path, strip the
 // environment string before testing
 aliasEnd = wxString::npos;
 
 if( aFileName.StartsWith( wxS( "${" ) ) )
 aliasEnd = aFileName.find( '}' );
 else if( aFileName.StartsWith( wxS( "$(" ) ) )
 aliasEnd = aFileName.find( ')' );
 
 if( aliasEnd != wxString::npos )
 lpath = aFileName.substr( aliasEnd + 1 );
 
 }
 
 // Test for forbidden chars in filenames. Should be wxFileName::GetForbiddenChars()
 // On MSW, the list returned by wxFileName::GetForbiddenChars() contains separators
 // '\'and '/' used here because lpath can be a full path.
 // So remove separators
 wxString lpath_no_sep = lpath;
#ifdef __WINDOWS__
 lpath_no_sep.Replace( "/", " " );
 lpath_no_sep.Replace( "\\", " " );
 
 // A disk identifier is allowed, and therefore remove its separator
 if( lpath_no_sep.Length() > 1 && lpath_no_sep[1] == ':' )
 lpath_no_sep[1] = ' ';
#endif
 
 if( wxString::npos != lpath_no_sep.find_first_of( wxFileName::GetForbiddenChars() ) )
 return false;
 
 return true;
}
 
 
bool FILENAME_RESOLVER::GetKicadPaths( std::list< wxString >& paths ) const
{
 paths.clear();
 
 if( !m_pgm )
 return false;
 
 bool hasKisys3D = false;
 
 
 // iterate over the list of internally defined ENV VARs
 // and add them to the paths list
 ENV_VAR_MAP_CITER mS = m_pgm->GetLocalEnvVariables().begin();
 ENV_VAR_MAP_CITER mE = m_pgm->GetLocalEnvVariables().end();
 
 while( mS != mE )
 {
 // filter out URLs, template directories, and known system paths
 if( mS->first == wxS( "KICAD_PTEMPLATES" )
 || mS->first.Matches( wxS( "KICAD*_FOOTPRINT_DIR") ) )
 {
 ++mS;
 continue;
 }
 
 if( wxString::npos != mS->second.GetValue().find( wxS( "://" ) ) )
 {
 ++mS;
 continue;
 }
 
 //also add the path without the ${} to act as legacy alias support for older files
 paths.push_back( mS->first );
 
 if( mS->first.Matches( wxS("KICAD*_3DMODEL_DIR") ) )
 hasKisys3D = true;
 
 ++mS;
 }
 
 if( !hasKisys3D )
 paths.emplace_back( ENV_VAR::GetVersionedEnvVarName( wxS( "3DMODEL_DIR" ) ) );
 
 return true;
}