Initial revision

modules/src/system/open.c

@@ -0,0 +1,53 @@
+/* $Header$ */
+
+#include <system.h>
+
+extern File *_get_entry();
+
+int
+sys_open(path, flag, filep)
+	char *path;
+	int flag;
+	File **filep;
+{
+	register fd;
+	register File *fp;
+	int open_mode;
+	long lseek();
+
+	switch (flag) {
+	case OP_READ:
+		open_mode = 0;
+		break;
+	case OP_WRITE:
+	case OP_APPEND:
+		open_mode = 1;
+		break;
+	default:
+		return 0;
+	}
+	if ((fp = _get_entry()) == (File *)0)
+		return 0;
+	if (flag == OP_WRITE) {
+		if ((fd = creat(path, 0644)) < 0)
+			return 0;
+	}
+	else /* OP_READ or OP_APPEND */
+	if ((fd = open(path, open_mode)) < 0) {
+		if (flag == OP_READ || access(path, 0) == 0)
+			return 0;
+		/* now: flag == OP_APPEND */
+		if ((fd = creat(path, 0644)) < 0)
+			return 0;
+	}
+	else {
+		if (flag == OP_APPEND && (lseek(fd, 0L, 2) < 0L)) {
+			close(fd);
+			return 0;
+		}
+	}
+	fp->o_flags = flag;
+	fp->o_fd = fd;
+	*filep = fp;
+	return 1;
+}