Enter your search terms Submit search form
	Web pdp-10.trailing-edge.com

 %TITLE 'UFBUFFER - find a buffer'
MODULE UFBUFFER (				! Find a buffer
		IDENT = '1-004'			! File: UFBUFFER.BLI Edit: STS1004
		) =
BEGIN
!COPYRIGHT (c) DIGITAL EQUIPMENT CORPORATION 1981, 1988.  ALL RIGHTS RESERVED.
!
!THIS SOFTWARE IS FURNISHED UNDER A LICENSE AND MAY BE USED AND COPIED ONLY
!IN ACCORDANCE WITH THE TERMS OF SUCH LICENSE AND WITH THE INCLUSION OF 
!THE ABOVE COPYRIGHT NOTICE.  THIS SOFTWARE OR ANY OTHER COPIES THEREOF MAY 
!NOT BE PROVIDED OR OTHERWISE MADE AVAILABLE TO ANY OTHER PERSON.  NO TITLE
!TO AND OWNERSHIP OF THE SOFTWARE IS HEREBY TRANSFERRED.
!
!THE INFORMATION IN THIS SOFTWARE IS SUBJECT TO CHANGE WITHOUT NOTICE AND 
!SHOULD NOT BE CONSTRUED AS A COMMITMENT BY DIGITAL EQUIPMENT CORPORATION.
!
!DIGITAL ASSUMES NO RESPONSIBILITY FOR THE USE OR RELIABILITY OF ITS 
!SOFTWARE ON EQUIPMENT THAT IS NOT SUPPLIED BY DIGITAL.
!
!
!++
! FACILITY:	EDT -- The DEC Standard Editor
!
! ABSTRACT:
!
!	Find a buffer, given its name.  A buffer is created if necessary.
!
! ENVIRONMENT:	Runs at any access mode - AST reentrant
!
! AUTHOR: Bob Kushlis, CREATION DATE: February 7, 1978
!
! MODIFIED BY:
!
! 1-001	- Original.  DJS 19-FEB-1981.  This module was created by
!	extracting routine EDT$$FND_BUF  from module UTIL.
! 1-002	- Regularized headers.  JBS 25-Feb-1981
! 1-003	- Fix module name.  JBS 11-Mar-1981
! 1-004 - Initialize more of the tbcb. STS 10-Mar-1982
!--

%SBTTL 'Declarations'
!
! TABLE OF CONTENTS:
!

REQUIRE 'EDTSRC:TRAROUNAM';

FORWARD ROUTINE
    EDT$$FND_BUF;

!
! INCLUDE FILES:
!

REQUIRE 'EDTSRC:EDTREQ';

!
! MACROS:
!
!	NONE
!
! EQUATED SYMBOLS:
!
!	NONE
!
! OWN STORAGE:
!
!	NONE
!
! EXTERNAL REFERENCES:
!
!	In the routine
%SBTTL 'EDT$$FND_BUF  - find a buffer'

GLOBAL ROUTINE EDT$$FND_BUF (			! Find a buffer
	NAME, 					! pointer to the buffer name
	LEN					! length of that name
    ) =

!++
! FUNCTIONAL DESCRIPTION:
!
!	This routine searches for a buffer with a specified name and positions
!	into it.  If  a buffer by that name does not exist, then it is created.
!	The global variable PRV_BUF  is set to point to the TBCB
!	of the buffer we were originally positioned in.
!
! FORMAL PARAMETERS:
!
!  NAME			Pointer to a string containing the name of the buffer.
!
!  LEN			Length of the name string.
!
! IMPLICIT INPUTS:
!
!	CUR_BUF
!
! IMPLICIT OUTPUTS:
!
!	CUR_BUF
!	PRV_BUF
!
! ROUTINE VALUE
!
!	Returns 1 if the buffer was found or created, 0 if an attempt to create a
!	new buffer failed.
!
! SIDE EFFECTS:
!
!	May create a new buffer.
!
!--

    BEGIN

    EXTERNAL ROUTINE
	EDT$$GET_BUFPTR,
	EDT$$NEW_BUF;

    EXTERNAL
	LNO_ZERO : LN_BLOCK,
	CUR_BUF : REF TBCB_BLOCK,	! Pointer to current buffer TBCB
	PRV_BUF : REF TBCB_BLOCK;	! Pointer to previous buffer TBCB

    LOCAL
	BUF_ADDR : REF TBCB_BLOCK,
	NEW;

!+
! Look for the buffer.
!-

    IF EDT$$GET_BUFPTR (.NAME, .LEN, BUF_ADDR, NEW)
    THEN
	BEGIN
!+
! Position to the new buffer.
!-
	PRV_BUF = .CUR_BUF;
	CUR_BUF = .BUF_ADDR;
!+
! If the buffer was new, then open it up.
!-

	IF (.NEW NEQ 0) THEN 
	    BEGIN
	    BUF_ADDR[TBCB_INPUT_RAB] = 0;
	    BUF_ADDR [TBCB_LINE_COUNT] = .LNO_ZERO [LN_LO];
	    BUF_ADDR [TBCB_LC_M] = .LNO_ZERO [LN_MD];
	    BUF_ADDR [TBCB_LC_H] = .LNO_ZERO [LN_HI];
	    EDT$$NEW_BUF ();
	    END;	    

	RETURN (1);
	END
    ELSE
	RETURN (0);

    END;


END
ELUDOM