/*****
 ** ** Module Header ******************************************************* **
 ** 									     **
 **   Modules Revision 3.0						     **
 **   Providing a flexible user environment				     **
 ** 									     **
 **   File:		ModuleCmd_Use.c					     **
 **   First Edition:	1991/10/23					     **
 ** 									     **
 **   Authors:	John Furlan, jlf@behere.com				     **
 **		Jens Hamisch, jens@Strawberry.COM			     **
 **		R.K. Owen, <rk@owen.sj.ca.us> or <rkowen@nersc.gov>	     **
 ** 									     **
 **   Description:	Prepends (and appends) directories to the MODULEPATH **
 **			environment variable to enable access to more	     **
 **			modulefiles.					     **
 ** 									     **
 **   Exports:		ModuleCmd_Use					     **
 **			ModuleCmd_UnUse					     **
 ** 									     **
 **   Notes:								     **
 ** 									     **
 ** ************************************************************************ **
 ****/

/** ** Copyright *********************************************************** **
 ** 									     **
 ** Copyright 1991-1994 by John L. Furlan.                      	     **
 ** see LICENSE.GPL, which must be provided, for details		     **
 ** 									     ** 
 ** ************************************************************************ **/

static char Id[] = "@(#)$Id: ModuleCmd_Use.c,v 1.13 2009/09/02 20:37:38 rkowen Exp $";
static void *UseId[] = { &UseId, Id };

/** ************************************************************************ **/
/** 				      HEADERS				     **/
/** ************************************************************************ **/

#include "modules_def.h"

/** ************************************************************************ **/
/** 				  LOCAL DATATYPES			     **/
/** ************************************************************************ **/

/** not applicable **/

/** ************************************************************************ **/
/** 				     CONSTANTS				     **/
/** ************************************************************************ **/

/** not applicable **/

/** ************************************************************************ **/
/**				      MACROS				     **/
/** ************************************************************************ **/

/** not applicable **/

/** ************************************************************************ **/
/** 				    LOCAL DATA				     **/
/** ************************************************************************ **/

static	char	module_name[] = __FILE__;

/** ************************************************************************ **/
/**				    PROTOTYPES				     **/
/** ************************************************************************ **/


#ifdef BEGINENV
/*++++
 ** ** Function-Header ***************************************************** **
 ** 									     **
 **   Function:		append_to_modulesbeginenv			     **
 ** 									     **
 **   Description:	Append the passed variable (with value) to the begin-**
 **			ning environment				     **
 ** 									     **
 **   First Edition:	1991/10/23					     **
 ** 									     **
 **   Parameters:	Tcl_Interp	*interp		Attached Tcl Interp. **
 **			char 		*var		Name of the variable **
 ** 									     **
 **   Result:		-						     **
 ** 									     **
 **   Attached Globals:	-						     **
 ** 									     **
 ** ************************************************************************ **
 ++++*/

static	void	append_to_modulesbeginenv(	Tcl_Interp	*interp,
						char		*var)
{
    char	*filename,		/** The filename, where the begin-   **/
					/** ning environment resides	     **/
		*val;			/** Value of the passed variable     **/
    FILE	*file;			/** File read handle		     **/

    if(	var
#if BEGINENV == 99
	&& Tcl_GetVar2( interp,"env","MODULESBEGINENV", TCL_GLOBAL_ONLY)
#endif
	) {
	/**
	 **  Get filename and the value of the passed variable
	 **/
	if( (filename = (char *) Tcl_GetVar2( interp, "env","_MODULESBEGINENV_",
	    TCL_GLOBAL_ONLY)) ) {
	    val = (char *) Tcl_GetVar2( interp, "env", var, TCL_GLOBAL_ONLY);

	    /**
	     **  Append the string <var>=<value>
	     **/

            if( NULL != (file = fopen( filename, "a+"))) {
                fprintf( file, "%s=%s\n", var, val);
                if( EOF == fclose( file))
		    ErrorLogger( ERR_CLOSE, LOC, filename, NULL);
            } else {
		ErrorLogger( ERR_OPEN, LOC, filename, _(em_appending), NULL);
	    }

        } /** if( get filename) **/
    } /** if( var passed) **/

} /** End of 'append_to_modulesbeginenv' **/
#else
#  define append_to_modulesbeginenv( a, b) {}
#endif

/*++++
 ** ** Function-Header ***************************************************** **
 ** 									     **
 **   Function:		ModuleCmd_Use					     **
 ** 									     **
 **   Description:	Execution of the module-command 'use'		     **
 ** 									     **
 **   First Edition:	1991/10/23					     **
 ** 									     **
 **   Parameters:	Tcl_Interp	*interp		Attached Tcl Interp. **
 **			int		 argc		Number of arguments  **
 **			char 		*argv[]		Argument list	     **
 ** 									     **
 **   Result:		int	TCL_ERROR	Failure			     **
 **				TCL_OK		Successful operation	     **
 ** 									     **
 **   Attached Globals:	g_flags		Controllig the callback functions    **
 ** 									     **
 ** ************************************************************************ **
 ++++*/

int ModuleCmd_Use(
	Tcl_Interp * interp,
	int argc,
	char *argv[]
) {
	struct stat     stats;		/** Buffer for the stat() systemcall **/
	char           *pathargv[4];	/** Argument buffer for Tcl calls    **/
	Tcl_Obj       **objv;		/** Tcl Object vector **/
	int             objc,		/** Tcl Object vector count **/
	                i;

    /**
     **  Parameter check. Usage is 'module use <path> [ <path> ... ]'
     **/
	if (argc < 1) {
		if (OK !=
		    ErrorLogger(ERR_USAGE, LOC,
				"use [-a|--append] dir [dir ...]", NULL))
			return (TCL_ERROR); /** ------ EXIT (FAILURE) -----> **/
	}

    /**
     **  Remove is done by another subroutine
     **/

	if (g_flags & M_REMOVE)
		return (ModuleCmd_UnUse(interp, argc, argv));

    /**
     **  Append or prepend the new module path
     **/

	if (append_flag) {
		pathargv[0] = "append-path";
	} else {
		pathargv[0] = "prepend-path";
	}

    /**
     **  Append (prepend) all passed paths to MODULEPATH in case they do exist,
     **  and are readable directories
     **/

	pathargv[1] = "MODULEPATH";
	pathargv[3] = NULL;

	for (i = 0; i < argc; i++) {
	/**
	 **  Check for -a|--append flag (if in modulefile - it's not parsed
	 **	by getoptlong) (keep -append for backward compatibility)
	 **/
		if ((!strcmp("-a", argv[i])) || (!strcmp("--append", argv[i]))
		    || (!strcmp("-append", argv[i]))) {

			pathargv[0] = "append-path";
			continue;

		} else if (stat(argv[i], &stats) < 0) {
	/**
	 **  Check for existing, readable directories
	 **/
			if (OK !=
			    ErrorLogger(ERR_DIRNOTFOUND, LOC, argv[i], NULL))
				return (TCL_ERROR); /** -- EXIT (FAILURE) -> **/
		} else if (!S_ISDIR(stats.st_mode)) {
			if (OK != ErrorLogger(ERR_NODIR, LOC, argv[i], NULL))
				return (TCL_ERROR); /** -- EXIT (FAILURE) -> **/
		}

	/**
	 **  Used the 'cmdSetPath' callback function to modify the MODULEPATH
	 **/

		pathargv[2] = argv[i];

		/* convert from argv to objv */
		Tcl_ArgvToObjv(&objc, &objv, -1, (char **) pathargv);
		if (cmdSetPath((ClientData) 0, interp, objc, objv) == TCL_ERROR)
			return (TCL_ERROR); /** ------ EXIT (FAILURE) -----> **/
	} /** for **/

    /**
     **  Add the new value of MODULESPATH to the end
     **  of the beginenvcache so that update will be able to find its
     **  modulefiles.
     **/

	append_to_modulesbeginenv(interp, "MODULEPATH");

	return (TCL_OK);

} /** End of 'ModuleCmd_Use' **/

/*++++
 ** ** Function-Header ***************************************************** **
 ** 									     **
 **   Function:		ModuleCmd_UnUse					     **
 ** 									     **
 **   Description:	Execution of the module-command 'unuse'		     **
 ** 									     **
 **   First Edition:	1991/10/23					     **
 ** 									     **
 **   Parameters:	Tcl_Interp	*interp		Attached Tcl Interp. **
 **			int		 argc		Number of arguments  **
 **			char 		*argv[]		Argument list	     **
 ** 									     **
 **   Result:		int	TCL_ERROR	Failure			     **
 **				TCL_OK		Successful operation	     **
 ** 									     **
 **   Attached Globals:	-						     **
 ** 									     **
 ** ************************************************************************ **
 ++++*/

int ModuleCmd_UnUse(
	Tcl_Interp * interp,
	int argc,
	char *argv[]
) {
	char           *pathargv[4];	/** Argument buffer for Tcl calls    **/
	Tcl_Obj       **objv;		/** Tcl Object vector **/
	int             objc,		/** Tcl Object vector count **/
	                i = 0;
    /**
     **  Parameter check. Usage is 'module use <path> [ <path> ... ]'
     **/
	if (argc < 1) {
		if (OK !=
		    ErrorLogger(ERR_USAGE, LOC, "unuse dir [dir ...]", NULL))
			return (TCL_ERROR); /** ------ EXIT (FAILURE) -----> **/
	}

    /**
     **  Remove all passed paths from MODULEPATH
     **	 Use the 'cmdSetPath' callback function to modify the MODULEPATH
     **/

	pathargv[0] = "remove-path";
	pathargv[1] = "MODULEPATH";
	pathargv[3] = NULL;

	for (i = 0; i < argc; i++) {
		pathargv[2] = argv[i];
		/* convert from argv to objv */
		Tcl_ArgvToObjv(&objc, &objv, -1, (char **) pathargv);
		if (cmdRemovePath((ClientData) 0, interp, objc, objv) ==
		    TCL_ERROR)
			return (TCL_ERROR); /** ------ EXIT (FAILURE) -----> **/
	} /** for **/
    /**
     **  Add the new value of MODULESPATH to the end
     **  of the beginenvcache so that update will be able to find its
     **  modulefiles.
     **/

	append_to_modulesbeginenv(interp, "MODULEPATH");

	return (TCL_OK);

} /** End of 'ModuleCmd_UnUse' **/