modulpsr.c

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  struct token *theToken,
  struct defmodule *theDefmodule)
  {
   int error;

   /*=============================*/
   /* The import and export lists */
   /* are initially empty.        */
   /*=============================*/

   theDefmodule->importList = NULL;
   theDefmodule->exportList = NULL;

   /*==========================================*/
   /* Parse import/export specifications until */
   /* a right parenthesis is encountered.      */
   /*==========================================*/

   while (theToken->type != RPAREN)
     {
      /*========================================*/
      /* Look for the opening left parenthesis. */
      /*========================================*/

      if (theToken->type != LPAREN)
        {
         SyntaxErrorMessage(theEnv,"defmodule");
         return(TRUE);
        }

      /*====================================*/
      /* Look for the import/export keyword */
      /* and call the appropriate functions */
      /* for parsing the specification.     */
      /*====================================*/

      GetToken(theEnv,readSource,theToken);

      if (theToken->type != SYMBOL)
        {
         SyntaxErrorMessage(theEnv,"defmodule");
         return(TRUE);
        }

      if (strcmp(ValueToString(theToken->value),"import") == 0)
        {
         error = ParseImportSpec(theEnv,readSource,theToken,theDefmodule);
        }
      else if (strcmp(ValueToString(theToken->value),"export") == 0)
        {
         error = ParseExportSpec(theEnv,readSource,theToken,theDefmodule,NULL);
        }
      else
        {
         SyntaxErrorMessage(theEnv,"defmodule");
         return(TRUE);
        }

      if (error) return(TRUE);

      /*============================================*/
      /* Begin parsing the next port specification. */
      /*============================================*/

      PPCRAndIndent(theEnv);
      GetToken(theEnv,readSource,theToken);

      if (theToken->type == RPAREN)
        {
         PPBackup(theEnv);
         PPBackup(theEnv);
         SavePPBuffer(theEnv,")");
        }
     }

   /*===================================*/
   /* Return FALSE to indicate no error */
   /* occurred while parsing the        */
   /* import/export specifications.     */
   /*===================================*/

   return(FALSE);
  }

/**********************************************************/
/* ParseImportSpec: Parses import specifications found in */
/*   a defmodule construct.                               */
/*                                                        */
/* <import-spec> ::= (import <module-name> <port-item>)   */
/*                                                        */
/* <port-item>   ::= ?ALL |                               */
/*                   ?NONE |                              */
/*                   <construct-name> ?ALL |              */
/*                   <construct-name> ?NONE |             */
/*                   <construct-name> <names>*            */
/**********************************************************/
static int ParseImportSpec(
  void *theEnv,
  char *readSource,
  struct token *theToken,
  struct defmodule *newModule)
  {
   struct defmodule *theModule;
   struct portItem *thePort, *oldImportSpec;
   int found, count;

   /*===========================*/
   /* Look for the module name. */
   /*===========================*/

   SavePPBuffer(theEnv," ");

   GetToken(theEnv,readSource,theToken);

   if (theToken->type != SYMBOL)
     {
      SyntaxErrorMessage(theEnv,"defmodule import specification");
      return(TRUE);
     }

   /*=====================================*/
   /* Verify the existence of the module. */
   /*=====================================*/

   if ((theModule = (struct defmodule *)
                    EnvFindDefmodule(theEnv,ValueToString(theToken->value))) == NULL)
     {
      CantFindItemErrorMessage(theEnv,"defmodule",ValueToString(theToken->value));
      return(TRUE);
     }

   /*========================================*/
   /* If the specified module doesn't export */
   /* any constructs, then the import        */
   /* specification is meaningless.          */
   /*========================================*/

   if (theModule->exportList == NULL)
     {
      NotExportedErrorMessage(theEnv,EnvGetDefmoduleName(theEnv,theModule),NULL,NULL);
      return(TRUE);
     }

   /*==============================================*/
   /* Parse the remaining portion of the import    */
   /* specification and return if an error occurs. */
   /*==============================================*/

   oldImportSpec = newModule->importList;
   if (ParseExportSpec(theEnv,readSource,theToken,newModule,theModule)) return(TRUE);

   /*========================================================*/
   /* If the ?NONE keyword was used with the import spec,    */
   /* then no constructs were actually imported and the      */
   /* import spec does not need to be checked for conflicts. */
   /*========================================================*/

   if (newModule->importList == oldImportSpec) return(FALSE);

   /*======================================================*/
   /* Check to see if the construct being imported can be  */
   /* by the specified module. This check exported doesn't */
   /* guarantee that a specific named construct actually   */
   /* exists. It just checks that it could be exported if  */
   /* it does exists.                                      */
   /*======================================================*/

   if (newModule->importList->constructType != NULL)
     {
      /*=============================*/
      /* Look for the construct in   */
      /* the module that exports it. */
      /*=============================*/

      found = FALSE;
      for (thePort = theModule->exportList;
           (thePort != NULL) && (! found);
           thePort = thePort->next)
        {
         if (thePort->constructType == NULL) found = TRUE;
         else if (thePort->constructType == newModule->importList->constructType)
           {
            if (newModule->importList->constructName == NULL) found = TRUE;
            else if (thePort->constructName == NULL) found = TRUE;
            else if (thePort->constructName == newModule->importList->constructName)
              { found = TRUE; }
           }
        }

      /*=======================================*/
      /* If it's not exported by the specified */
      /* module, print an error message.       */
      /*=======================================*/

      if (! found)
        {
         if (newModule->importList->constructName == NULL)
           {
            NotExportedErrorMessage(theEnv,EnvGetDefmoduleName(theEnv,theModule),
                                    ValueToString(newModule->importList->constructType),
                                    NULL);
           }
         else
           {
            NotExportedErrorMessage(theEnv,EnvGetDefmoduleName(theEnv,theModule),
                                    ValueToString(newModule->importList->constructType),
                                    ValueToString(newModule->importList->constructName));
           }
         return(TRUE);
        }
     }

   /*======================================================*/
   /* Verify that specific named constructs actually exist */
   /* and can be seen from the module importing them.      */
   /*======================================================*/

   SaveCurrentModule(theEnv);
   EnvSetCurrentModule(theEnv,(void *) newModule);

   for (thePort = newModule->importList;
        thePort != NULL;
        thePort = thePort->next)
     {
      if ((thePort->constructType == NULL) || (thePort->constructName == NULL))
        { continue; }

      theModule = (struct defmodule *)
                  EnvFindDefmodule(theEnv,ValueToString(thePort->moduleName));
      EnvSetCurrentModule(theEnv,theModule);
      if (FindImportedConstruct(theEnv,ValueToString(thePort->constructType),NULL,
                                ValueToString(thePort->constructName),&count,
                                TRUE,FALSE) == NULL)
        {
         NotExportedErrorMessage(theEnv,EnvGetDefmoduleName(theEnv,theModule),
                                 ValueToString(thePort->constructType),
                                 ValueToString(thePort->constructName));
         RestoreCurrentModule(theEnv);
         return(TRUE);
        }
     }

   RestoreCurrentModule(theEnv);

   /*===============================================*/
   /* The import list has been successfully parsed. */
   /*===============================================*/

   return(FALSE);
  }

/**********************************************************/
/* ParseExportSpec: Parses export specifications found in */
/*   a defmodule construct. This includes parsing the     */
/*   remaining specification found in an import           */
/*   specification after the module name.                 */
/**********************************************************/
static int ParseExportSpec(
  void *theEnv,
  char *readSource,
  struct token *theToken,
  struct defmodule *newModule,
  struct defmodule *importModule)
  {
   struct portItem *newPort;
   SYMBOL_HN *theConstruct, *moduleName;
   struct portConstructItem *thePortConstruct;
   char *errorMessage;

   /*===========================================*/
   /* Set up some variables for error messages. */
   /*===========================================*/

   if (importModule != NULL)
     {
      errorMessage = "defmodule import specification";
      moduleName = importModule->name;
     }
   else
     {
      errorMessage = "defmodule export specification";
      moduleName = NULL;
     }

   /*=============================================*/
   /* Handle the special variables ?ALL and ?NONE */
   /* in the import/export specification.         */
   /*=============================================*/

   SavePPBuffer(theEnv," ");
   GetToken(theEnv,readSource,theToken);

   if (theToken->type == SF_VARIABLE)
     {
      /*==============================*/
      /* Check to see if the variable */
      /* is either ?ALL or ?NONE.     */
      /*==============================*/

      if (strcmp(ValueToString(theToken->value),"ALL") == 0)
        {
         newPort = (struct portItem *) get_struct(theEnv,portItem);
         newPort->moduleName = moduleName;
         newPort->constructType = NULL;
         newPort->constructName = NULL;
         newPort->next = NULL;
        }
      else if (strcmp(ValueToString(theToken->value),"NONE") == 0)
        { newPort = NULL; }
      else
        {
         SyntaxErrorMessage(theEnv,errorMessage);
         return(TRUE);
        }

      /*=======================================================*/
      /* The export/import specification must end with a right */
      /* parenthesis after ?ALL or ?NONE at this point.        */
      /*=======================================================*/

      GetToken(theEnv,readSource,theToken);

      if (theToken->type != RPAREN)
        {
         if (newPort != NULL) rtn_struct(theEnv,portItem,newPort);
         PPBackup(theEnv);
         SavePPBuffer(theEnv," ");
         SavePPBuffer(theEnv,theToken->printForm);
         SyntaxErrorMessage(theEnv,errorMessage);
         return(TRUE);
        }

      /*=====================================*/
      /* Add the new specification to either */
      /* the import or export list.          */
      /*=====================================*/

      if (newPort != NULL)
        {
         if (importModule != NULL)
           {
            newPort->next = newModule->importList;
            newModule->importList = newPort;
           }
         else
           {
            newPort->next = newModule->exportList;
            newModule->exportList = newPort;
           }
        }

      /*============================================*/
      /* Return FALSE to indicate the import/export */
      /* specification was successfully parsed.     */
      /*============================================*/

      return(FALSE);
     }

   /*========================================================*/
   /* If the ?ALL and ?NONE keywords were not used, then the */
   /* token must be the name of an importable construct.     */
   /*========================================================*/

   if (theToken->type != SYMBOL)
     {
      SyntaxErrorMessage(theEnv,errorMessage);
      return(TRUE);
     }

   theConstruct = (SYMBOL_HN *) theToken->value;

   if ((thePortConstruct = ValidPortConstructItem(theEnv,ValueToString(theConstruct))) == NULL)
     {
      SyntaxErrorMessage(theEnv,errorMessage);
      return(TRUE);
     }

   /*=============================================================*/