Initial import of the CDE 2.1.30 sources from the Open Group.

cde/lib/tt/mini_isam/isopen.c

@@ -0,0 +1,106 @@
+/*%%  (c) Copyright 1993, 1994 Hewlett-Packard Company			 */
+/*%%  (c) Copyright 1993, 1994 International Business Machines Corp.	 */
+/*%%  (c) Copyright 1993, 1994 Sun Microsystems, Inc.			 */
+/*%%  (c) Copyright 1993, 1994 Novell, Inc. 				 */
+/*%%  $XConsortium: isopen.c /main/3 1995/10/23 11:42:40 rswiston $ 			 				 */
+#ifndef lint
+static char sccsid[] = "@(#)isopen.c 1.12 89/07/17 Copyr 1988 Sun Micro";
+#endif
+/*
+ * Copyright (c) 1988 by Sun Microsystems, Inc.
+ */
+
+/*
+ * isopen.c
+ *
+ * Description:
+ *	Open an ISAM file. 
+ */
+
+#include "isam_impl.h"
+#include <netdb.h>     
+#include <sys/file.h>
+#include <sys/time.h>
+
+extern char _isam_version[];
+static char *_version_ = _isam_version;
+
+static int _am_open();
+/*
+ * isfd = isopen(isfname, mode)
+ *
+ * Isopen() determines on which machine the ISAM file resides, 
+ * checks if the file exists, creates a File access block,
+ * and initilizes it. It also checks permissions. Returns an ISAM file
+ * descriptor (isfd), or a value of -1 if the open failed.
+ *
+ * Errors:
+ *	EBADARG	Improper mode parameter
+ *	EBADFILE ISAM file is corrupted or it is not an NetISAM file
+ *	EFLOCKED The file is exclusively locked by other process.
+ *	EFNAME	Invalid ISAM file name 
+ *	EFNAME	ISAM file does not exist
+ *	ETOOMANY Too many ISAM file descriptors are in use (128 is the limit)
+ *
+ * The following error code is "borrowed" from UNIX:
+ *	EACCES	UNIX file system protection denies access to the file:
+ *	         - mode is INOUT or OUTPUT and ISAM file is on 
+ *	           a Read-Only mounted file system
+ *		 - UNIX file permissions don't allow access to the file
+ */
+
+int 
+isopen(isfname, mode)
+    char		*isfname;
+    int			mode;
+{
+    Fab			*fab;
+    Isfd		isfd;
+    enum openmode	openmode;
+
+    /*
+     * Check if the user is allowed to access the ISAM file.
+     * Use UNIX and NFS permissions.
+     */
+
+    /* Get file open mode part of the mode parameter. */
+    if ((openmode = _getopenmode(mode)) == OM_BADMODE) {
+	_setiserrno2(EBADARG, '9', '0');
+	return (NOISFD);
+    }
+    /* Create a Fab object. */
+    fab = _fab_new(isfname,
+		   openmode,
+		   (Bool)((mode & ISLENMODE) == ISVARLEN),
+		   0,
+		   0);
+    if (fab == NULL) {
+	return (NOISFD);		     /* iserrno is set by fab_new */
+    }
+
+    /* Get an ISAM file descriptor for this fab */
+    if ((isfd = _isfd_insert(fab)) == NOISFD) {
+	/* Table of ISAM file descriptors would overflow. */
+	_fab_destroy(fab);
+	_setiserrno2(ETOOMANY, '9', '0');
+	return (NOISFD);
+    }
+    FAB_ISFDSET(fab, isfd);
+    if (_am_open(fab)) {
+	_seterr_errcode(&fab->errcode);
+	_fab_destroy(fab);
+	return (NOISFD);
+    }
+
+    isreclen = fab->maxreclen;
+
+    return ((int)isfd);			     /* Successful isopen() */
+}
+
+Static int _am_open(fab)
+    register Fab	*fab;
+{
+    return (_amopen(fab->isfname, fab->openmode, &fab->varlength,
+		    &fab->minreclen, &fab->maxreclen, &fab->isfhandle,
+		    &fab->curpos, &fab->errcode));
+}