cleanup in unistd.h and lockf

1 files changed, 74 insertions, 0 deletions

diff --git a/src/port/unistd.c b/src/port/unistd.c
new file mode 100644
index 0000000..7a931be
--- /dev/null
+++ b/src/port/unistd.c
@@ -0,0 +1,74 @@
+/*
+    Copyright (C) 2008 Andreas Baumann <abaumann@yahoo.com>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "port/unistd.h"
+
+#if !defined HAVE_LOCKF || defined TEST_HAVE_LOCKF
+
+#include "port/string.h"	/* for memset */
+#include "port/unistd.h"	/* for getpid */
+
+#include <errno.h>		/* for errno */
+
+int wolf_port_lockf( int fd, int cmd, off_t len ) {
+	struct flock fl;
+	
+	memset( (char *)&fl, 0, sizeof( fl ) );
+	/* lockf is always relative to the current file position. */
+	fl.l_whence = SEEK_CUR;
+	fl.l_start = 0;
+	fl.l_len = len;
+	
+	errno = 0;
+	
+	switch( cmd ) {
+		case F_TEST:
+			fl.l_type = F_RDLCK;
+			if( fcntl( fd, F_GETLK, &fl ) < 0 ) {
+				return -1;
+			}
+			if( fl.l_type == F_UNLCK ||
+			    fl.l_pid == getpid( ) ) {
+				return 0;
+			}
+			errno = EACCES;
+			return -1;
+			
+		case F_ULOCK:
+			fl.l_type = F_UNLCK;
+			cmd = F_SETLK;
+			break;
+		
+		case F_LOCK:
+			fl.l_type = F_WRLCK;
+			cmd = F_SETLKW;
+			break;
+		
+		case F_TLOCK:
+			fl.l_type = F_WRLCK;
+			cmd = F_SETLK; 
+			break;
+			
+		default:
+			errno = EINVAL;
+			return -1;
+	}
+	
+	return fcntl( fd, cmd, &fl );
+}
+
+#endif /* !defined HAVE_LOCKF || defined TEST_HAVE_LOCKF */