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CPM OPERATING SYSTEMS/CPM 68K/1.0X SOURCES/v102a/clib/xopen.c

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+/***************************************************************************
+ *									    
+ *			_ _ o p e n   F u n c t i o n			    
+ *			-----------------------------			    
+ *	Copyright 1982 by Digital Research Inc.  All rights reserved.	    
+ *									    
+ *	Function "__open" is used to parse the CP/M fcb and open or create  
+ *	the requested file.  Created files are deleted first, to avoid 	    
+ *	directory problems.						    
+ *									    
+ *	Calling Sequence:						    
+ *									    
+ *		ret = __open(ch,filnam,bdosfunc);			    
+ *									    
+ *	Where:								    
+ *		ch	Is a vacant channel number			    
+ *		filnam	Is a null-terminated CP/M filename		    
+ *		bdosfunc Is the desired BDOS function to perform	    
+ *		ret	Is SUCCESS if everything ok, FAILURE o.w. unless:   
+ *			  bdosfunc=SEARCHF/N, ret = dcnt (0-3)		    
+ *									    
+ *	This routine may also be used to delete files as well.		    
+ *									    
+ *	Modified  4-Nov-83 (whf) open files read-only if appropriate	    
+ *	Modified  8-Oct-83 (whf) handle user #s differently		    
+ *	Modified  5-Oct-83 (whf) added '_parsefn()'			    
+ *	Modified 11-Aug-83 (whf) for DRC				    
+ *	Modified 26-Jun-83 (sw) for wild cards and user # support	    
+ *									    
+ ****************************************************************************/
+
+#include "portab.h"
+#include "osif.h"
+#include "osiferr.h"
+#include "errno.h"
+#define HIBIT 0x80
+
+WORD	__open(ch,filnam,bdosfunc)		/****************************/
+						/*			    */
+	WORD	ch;				/* Channel number	    */
+REG	BYTE	*filnam;			/* -> filename		    */
+	WORD	bdosfunc;			/* BDOS Function	    */
+{						/****************************/
+	FD	*fp;				/* -> ccb area		    */
+REG	struct fcbtab	*fcbp;			/* -> FCB area in ccb	    */
+REG	BYTE	*p;				/* Temp character pointer   */
+REG	WORD	rv;				/* Return value		    */
+REG	WORD	xuser;				/* User number		    */
+	BYTE	*_parsefn();			/* Parse filename function  */
+						/****************************/
+						/*			    */
+	fp = _getccb(ch);			/* Fetch ccb pointer	    */
+	fcbp = &(fp ->fcb);			/* Fetch fcb pointer	    */
+	rv = SUCCESS;				/* Default to success	    */
+						/****************************/
+	if( _parsefn(filnam,fcbp) != NULLPTR )	/* Parse filnam into fcb    */
+		RETERR(FAILURE,EINVAL);		/* Quit if name not ok	    */
+#if CPM						/* Handling user numbers?   */
+	if(fcbp->fuser)				/* User # specified?	    */
+		fp->user = fcbp->fuser;		/* put it where we use it   */
+#endif						/****************************/
+	if( bdosfunc == CREATE  &&  		/* Creating file?	    */
+	    index(fcbp->fname,'?'))		/* Wild cards @!@#$!!!	    */
+		RETERR(FAILURE,EINVAL);		/* Just quit		    */
+						/*			    */
+	xuser = _chkuser(fp->user);		/* Change user # if needed  */
+						/*			    */
+	if(bdosfunc == CREATE)			/* Creating file?	    */
+		__OSIF(DELETE,fcbp);		/*  delete it first	    */
+						/*			    */
+#if CPM						/* running some brand of CPM*/
+	if(bdosfunc == OPEN)			/* Opening a file?	    */
+	{					/* Yes...		    */
+	    if( fp->flags & ISREAD )		/* Open file Read-Only?	    */
+		(fcbp->fname)[5] |= HIBIT;	/* Turn on F6' attribute bit*/
+	}					/*			    */
+#endif						/*			    */
+						/****************************/
+	rv = __OSIF(bdosfunc,fcbp);		/* Do requested operation   */
+						/****************************/
+						/*			    */
+	_uchkuser(fp->user,xuser);		/* Change back if needed    */
+						/*			    */
+	if(bdosfunc == SEARCHF || bdosfunc == SEARCHN) /*		    */
+		return(rv);			/* return directory count   */
+	return((rv<=3) ? SUCCESS : FAILURE);	/* Binary return code	    */
+}						/****************************/