Initial source for rwtest/doio in LTP
diff --git a/lib/file_lock.c b/lib/file_lock.c
new file mode 100644
index 0000000..00eb582
--- /dev/null
+++ b/lib/file_lock.c
@@ -0,0 +1,209 @@
+/*
+ * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
+ * 
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * 
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ * 
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ * 
+ * http://www.sgi.com 
+ * 
+ * For further information regarding this notice, see: 
+ * 
+ * http://oss.sgi.com/projects/GenInfo/NoticeExplan/
+ */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/file.h>
+#include <sys/param.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <sys/sysmacros.h>
+#include <string.h> /* memset, strerror */
+
+extern int errno;
+
+#ifndef EFSEXCLWR
+#define EFSEXCLWR	503
+#endif
+
+/*
+ * String containing the last system call.
+ *
+ */
+char Fl_syscall_str[128];
+
+static char errmsg[256];
+
+/***********************************************************************
+ *
+ * Test interface to the fcntl system call.
+ * It will loop if the LOCK_NB flags is NOT set.
+ ***********************************************************************/
+int
+file_lock(fd, flags, errormsg)
+int fd;
+int flags;
+char **errormsg;
+{
+        register int cmd, ret;
+        struct flock flocks;
+
+        memset(&flocks, 0, sizeof(struct flock));
+
+        if (flags&LOCK_NB)
+                cmd = F_SETLK;
+        else
+                cmd = F_SETLKW;
+
+        flocks.l_whence = 0;
+        flocks.l_start = 0;
+        flocks.l_len = 0;
+
+        if (flags&LOCK_UN)
+                flocks.l_type = F_UNLCK;
+        else if (flags&LOCK_EX)
+                flocks.l_type = F_WRLCK;
+        else if (flags&LOCK_SH)
+                flocks.l_type = F_RDLCK;
+        else {
+                errno = EINVAL;
+	    if ( errormsg != NULL ) {
+		sprintf(errmsg,
+		    "Programmer error, called file_lock with in valid flags\n");
+		*errormsg = errmsg;
+            }
+            return -1;
+        }
+
+	sprintf(Fl_syscall_str,
+	    "fcntl(%d, %d, &flocks): type:%d whence:%d, start:%lld len:%lld\n",
+                fd, cmd, flocks.l_type, flocks.l_whence,
+		(long long)flocks.l_start, (long long)flocks.l_len);
+
+	while (1) {
+            ret = fcntl(fd, cmd, &flocks);
+
+	    if ( ret < 0 ) {
+	        if ( cmd == F_SETLK )
+	            switch (errno) {
+		       /* these errors are okay */
+		        case EACCES:	/* Permission denied */
+		        case EINTR:		/* interrupted system call */
+#ifdef EFILESH
+		        case EFILESH:	/* file shared */
+#endif
+		        case EFSEXCLWR:	/* File is write protected */
+			    continue;	/* retry getting lock */
+	        }
+	        if ( errormsg != NULL ) {
+	            sprintf(errmsg, "fcntl(%d, %d, &flocks): errno:%d %s\n",
+		        fd, cmd, errno, strerror(errno));
+		    *errormsg = errmsg;
+	        }
+	        return -1;
+	    }
+	    break;
+	}
+
+        return ret;
+
+}	/* end of file_lock */
+
+/***********************************************************************
+ *
+ * Test interface to the fcntl system call.
+ * It will loop if the LOCK_NB flags is NOT set.
+ ***********************************************************************/
+int
+record_lock(fd, flags, start, len, errormsg)
+int fd;
+int flags;
+int start;
+int len;
+char **errormsg;
+{
+        register int cmd, ret;
+        struct flock flocks;
+
+        memset(&flocks, 0, sizeof(struct flock));
+
+        if (flags&LOCK_NB)
+                cmd = F_SETLK;
+        else
+                cmd = F_SETLKW;
+
+        flocks.l_whence = 0;
+        flocks.l_start = start;
+        flocks.l_len = len;
+
+        if (flags&LOCK_UN)
+                flocks.l_type = F_UNLCK;
+        else if (flags&LOCK_EX)
+                flocks.l_type = F_WRLCK;
+        else if (flags&LOCK_SH)
+                flocks.l_type = F_RDLCK;
+        else {
+                errno = EINVAL;
+	    if ( errormsg != NULL ) {
+		sprintf(errmsg,
+		    "Programmer error, called record_lock with in valid flags\n");
+		*errormsg = errmsg;
+            }
+            return -1;
+        }
+
+	sprintf(Fl_syscall_str,
+	    "fcntl(%d, %d, &flocks): type:%d whence:%d, start:%lld len:%lld\n",
+                fd, cmd, flocks.l_type, flocks.l_whence,
+		(long long)flocks.l_start, (long long)flocks.l_len);
+
+	while (1) {
+            ret = fcntl(fd, cmd, &flocks);
+
+	    if ( ret < 0 ) {
+	        if ( cmd == F_SETLK )
+	            switch (errno) {
+		       /* these errors are okay */
+		        case EACCES:	/* Permission denied */
+		        case EINTR:		/* interrupted system call */
+#ifdef EFILESH
+		        case EFILESH:	/* file shared */
+#endif
+		        case EFSEXCLWR:	/* File is write protected */
+			    continue;	/* retry getting lock */
+	        }
+	        if ( errormsg != NULL ) {
+	            sprintf(errmsg, "fcntl(%d, %d, &flocks): errno:%d %s\n",
+		        fd, cmd, errno, strerror(errno));
+		    *errormsg = errmsg;
+	        }
+	        return -1;
+	    }
+	    break;
+	}
+
+        return ret;
+
+}	/* end of record_lock */
+
+