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(*                                                              *)
(*         Gardens Point Modula-2 Library Definition            *)
(*                                                              *)
(*                                                              *)
(*     (c) Copyright 1992 Faculty of Information Technology     *)
(*              Queensland University of Technology             *)
(*                                                              *)
(*     Permission is granted to use, copy and change this       *)
(*     program as long as the copyright message is left intact  *)
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(*                                                              *)
(*                File name lookup and create			*)
(*                                                              *)
(*      original module : kjg July 1992				*)
(*      modifications   : kjg  Sep 1992 lowercase default, use  *)
(*				GPNAMES=MIXED for mixed case... *)
(*                                                              *)
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DEFINITION MODULE GpFiles;

    FROM UxFiles IMPORT File;
(* 
 *	this module implements the gpm file lookup strategy.
 *	It was introduced to make the change from lower case
 *	to mixed case file names in a consistent manner for
 *	gpm, build, gpmake, gpscript, decode, mkenumio and
 *	other tools which lookup files based on module names.
 *	The lookup strategy is backward compatible with the
 *	filenames created by previous version of gpm.
 *
 *	  GPNAMES=MIXED			  GPNAMES=LOWER
 *	lookup(1) name as given;	lookup(1) lower case; 
 *	lookup(2) lower case;		lookup(2) name as given;
 *	lookup(3) DOS length;		lookup(3) DOS length;
 *)
    CONST fileNameLength    = 79;	(* max base name length *)
	  oldFileNameLength = 8; 	(* DOS compatibility    *)

    PROCEDURE GpCreateFile(	base : ARRAY OF CHAR;
				ext  : ARRAY OF CHAR;
			    VAR name : ARRAY OF CHAR;
			    VAR file : File);	(* NIL if can't create *)
    (*		Truncate base name at fileNameLength.    *)
    (*		If ext <> "" then a dot and the ext are  *)
    (*		appended, otherwise the base unchanged.  *)
    (*		Name is then made lower case unless the  *)
    (*		env variable GPNAMES has first character *)
    (*		"m" or "M" at module initialization time *)
    (*  post : name is the name of the created file	 *)

    PROCEDURE GpFilename(	base : ARRAY OF CHAR;
				ext  : ARRAY OF CHAR;
			    VAR name : ARRAY OF CHAR);
    (*		Truncate base name at fileNameLength.    *)
    (*		If ext <> "" then a dot and the ext are  *)
    (*		appended, otherwise the base unchanged.  *)
    (*		Name is then made lower case unless the  *)
    (*		env variable GPNAMES has first character *)
    (*		"m" or "M" at module initialization time *)
    (*  post : name is the name of the created file	 *)

    PROCEDURE GpFindLocal(	base : ARRAY OF CHAR;
				ext  : ARRAY OF CHAR;
			    VAR name : ARRAY OF CHAR;
			    VAR file : File);	(* or NIL if not found *)
    (*		Look for file in current directory ...	 *)
    (*		If ext <> "" then look for "base.ext",	 *)
    (*		else look for the file "base"		 *)
    (*  post : name is the name of the file, if found in *)
    (*		the current directory, else file = NIL   *)

    PROCEDURE GpFindOnPath(	path : ARRAY OF CHAR;
				base : ARRAY OF CHAR;
				ext  : ARRAY OF CHAR;
			    VAR name : ARRAY OF CHAR;
			    VAR file : File);	(* or NIL if not found *)
    (*		Look for file first in current directory, *)
    (*		then on the given path.			  *)
    (*		If ext <> "" then look for "base.ext",	  *)
    (*		else look for the file "base"		  *)
    (*		Actual "name" must be long enough for the *)
    (*		longest possible path name!		  *)
    (*  post : name is the pathname of the file, if 	  *)
    (*		file found, else file = NIL		  *)

END GpFiles.
