Add support for PCB and footprint format versioning

Currently, kicad_pcb files have a (version ...) tag, but it is ignored. This
commit does the following:

1. Parse the version. If it's later than the last supported version, present an
alternative error message suggesting an upgrade if the file does not load
correctly. The version will be interpreted as an integer YYYYMMDD to suggest
a KiCad release date.

2. Accept a (version ...) tag also in kicad_mod files, but do not write them
yet. If no version tag is present in these files, assume the version to be that
of the current format version at the time of this commit.

This is meant to be merged to the 4.x stable series, and preps for KiCad 5
which will start emitting version tags also in footprints - users with what
will then be 'old stable' will not get a parse error when we introduce this for
footprints, and we can safely increment the format version later.

pcbnew/pcb_parser.cpp

@@ -2,8 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2012 CERN
- * Copyright (C) 2012-2015 KiCad Developers, see change_log.txt for contributors.
- * @author Wayne Stambaugh <[email protected]>
+ * Copyright (C) 2012-2016 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
@@ -60,6 +59,8 @@ using namespace PCB_KEYS_T;
 
 void PCB_PARSER::init()
 {
+    m_tooRecent = false;
+    m_requiredVersion = 0;
     m_layerIndices.clear();
     m_layerMasks.clear();
 
@@ -169,6 +170,43 @@ bool PCB_PARSER::parseBool() throw( PARSE_ERROR )
 }
 
 
+int PCB_PARSER::parseVersion() throw( IO_ERROR, PARSE_ERROR )
+{
+    if( NextTok() != T_version )
+        Expecting( GetTokenText( T_version ) );
+
+    int pcb_version = parseInt( FromUTF8() );
+
+    NeedRIGHT();
+
+    return pcb_version;
+}
+
+
+wxString PCB_PARSER::GetRequiredVersion()
+{
+    int year, month, day;
+
+    year = m_requiredVersion / 10000;
+    month = ( m_requiredVersion / 100 ) - ( year * 100 );
+    day = m_requiredVersion - ( year * 10000 ) - ( month * 100 );
+
+    // wx throws an assertion, not a catchable exception, when the date is invalid.
+    // User input shouldn't give wx asserts, so check manually and throw a proper
+    // error instead
+    if( day <= 0 || month <= 0 || month > 12 ||
+            day > wxDateTime::GetNumberOfDays( (wxDateTime::Month)( month - 1 ), year ) )
+    {
+        wxString err;
+        err.Printf( _( "cannot interpret date code %d" ), m_requiredVersion );
+        THROW_PARSE_ERROR( err, CurSource(), CurLine(), CurLineNumber(), CurOffset() );
+    }
+
+    wxDateTime date( day, (wxDateTime::Month)( month - 1 ), year, 0, 0, 0, 0 );
+    return date.FormatDate();
+}
+
+
 wxPoint PCB_PARSER::parseXY() throw( PARSE_ERROR, IO_ERROR )
 {
     if( CurTok() != T_LEFT )
@@ -411,7 +449,23 @@ BOARD_ITEM* PCB_PARSER::Parse() throw( IO_ERROR, PARSE_ERROR )
 }
 
 
-BOARD* PCB_PARSER::parseBOARD() throw( IO_ERROR, PARSE_ERROR )
+BOARD* PCB_PARSER::parseBOARD() throw( IO_ERROR, PARSE_ERROR, FUTURE_FORMAT_ERROR )
+{
+    try
+    {
+        return parseBOARD_unchecked();
+    }
+    catch( const PARSE_ERROR& parse_error )
+    {
+        if( m_tooRecent )
+            throw FUTURE_FORMAT_ERROR( parse_error, GetRequiredVersion() );
+        else
+            throw;
+    }
+}
+
+
+BOARD* PCB_PARSER::parseBOARD_unchecked() throw( IO_ERROR, PARSE_ERROR )
 {
     T token;
 
@@ -506,24 +560,34 @@ void PCB_PARSER::parseHeader() throw( IO_ERROR, PARSE_ERROR )
     wxCHECK_RET( CurTok() == T_kicad_pcb,
                  wxT( "Cannot parse " ) + GetTokenString( CurTok() ) + wxT( " as a header." ) );
 
-    T token;
-
     NeedLEFT();
-    token = NextTok();
 
-    if( token != T_version )
-        Expecting( GetTokenText( T_version ) );
+    T tok = NextTok();
+    if( tok == T_version )
+    {
+        m_requiredVersion = parseInt( FromUTF8() );
+        m_tooRecent = ( m_requiredVersion > SEXPR_BOARD_FILE_VERSION );
+        NeedRIGHT();
 
-    // Get the file version.
-    m_board->SetFileFormatVersionAtLoad( parseInt( GetTokenText( T_version ) ) );
+        // Skip the host name and host build version information.
+        NeedLEFT();
+        NeedSYMBOL();
+        NeedSYMBOL();
+        NeedSYMBOL();
+        NeedRIGHT();
+    }
+    else
+    {
+        m_requiredVersion = SEXPR_BOARD_FILE_VERSION;
+        m_tooRecent = ( m_requiredVersion > SEXPR_BOARD_FILE_VERSION );
 
-    // Skip the host name and host build version information.
-    NeedRIGHT();
-    NeedLEFT();
-    NeedSYMBOL();
-    NeedSYMBOL();
-    NeedSYMBOL();
-    NeedRIGHT();
+        // Skip the host name and host build version information.
+        NeedSYMBOL();
+        NeedSYMBOL();
+        NeedRIGHT();
+    }
+
+    m_board->SetFileFormatVersionAtLoad( m_requiredVersion );
 }
 
 
@@ -1651,7 +1715,25 @@ DIMENSION* PCB_PARSER::parseDIMENSION() throw( IO_ERROR, PARSE_ERROR )
 }
 
 
-MODULE* PCB_PARSER::parseMODULE( wxArrayString* aInitialComments ) throw( IO_ERROR, PARSE_ERROR )
+MODULE* PCB_PARSER::parseMODULE( wxArrayString* aInitialComments )
+        throw( IO_ERROR, PARSE_ERROR, FUTURE_FORMAT_ERROR )
+{
+    try
+    {
+        return parseMODULE_unchecked( aInitialComments );
+    }
+    catch( const PARSE_ERROR& parse_error )
+    {
+        if( m_tooRecent )
+            throw FUTURE_FORMAT_ERROR( parse_error, GetRequiredVersion() );
+        else
+            throw;
+    }
+}
+
+
+MODULE* PCB_PARSER::parseMODULE_unchecked( wxArrayString* aInitialComments )
+        throw( IO_ERROR, PARSE_ERROR )
 {
     wxCHECK_MSG( CurTok() == T_module, NULL,
                  wxT( "Cannot parse " ) + GetTokenString( CurTok() ) + wxT( " as MODULE." ) );
@@ -1665,7 +1747,11 @@ MODULE* PCB_PARSER::parseMODULE( wxArrayString* aInitialComments ) throw( IO_ERR
 
     module->SetInitialComments( aInitialComments );
 
-    NeedSYMBOLorNUMBER();
+    token = NextTok();
+
+    if( !IsSymbol( token ) && token != T_NUMBER )
+        Expecting( "symbol|number" );
+
     name = FromUTF8();
 
     if( !name.IsEmpty() && fpid.Parse( FromUTF8() ) >= 0 )
@@ -1683,6 +1769,18 @@ MODULE* PCB_PARSER::parseMODULE( wxArrayString* aInitialComments ) throw( IO_ERR
 
         switch( token )
         {
+        case T_version:
+        {
+            // Theoretically a module nested in a PCB could declare its own version, though
+            // as of writing this comment we don't do that. Just in case, take the greater
+            // version.
+            int this_version = parseInt( FromUTF8() );
+            NeedRIGHT();
+            m_requiredVersion = std::max( m_requiredVersion, this_version );
+            m_tooRecent = ( m_requiredVersion > SEXPR_BOARD_FILE_VERSION );
+            break;
+        }
+
         case T_locked:
             module->SetLocked( true );
             break;