Skeleton job control interface

src/core/job.c

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 2 of the
+ * License, or 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, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <string.h>
+#include <errno.h>
+#include <gpxe/job.h>
+
+/** @file
+ *
+ * Job control interfaces
+ *
+ */
+
+void done ( struct job_interface *job, int rc ) {
+	struct job_interface *dest = job_dest ( job );
+
+	dest->op->done ( dest, rc );
+}
+
+/****************************************************************************
+ *
+ * Helper methods
+ *
+ * These functions are designed to be used as methods in the
+ * job_interface_operations table.
+ *
+ */
+
+void ignore_done ( struct job_interface *job __unused, int rc __unused ) {
+	/* Nothing to do */
+}
+
+void ignore_kill ( struct job_interface *job __unused ) {
+	/* Nothing to do */
+}
+
+void ignore_progress ( struct job_interface *job __unused,
+		       struct job_progress *progress ) {
+	memset ( progress, 0, sizeof ( *progress ) );
+}
+
+/** Null job control interface operations */
+struct job_interface_operations null_job_ops = {
+	.done		= ignore_done,
+	.kill		= ignore_kill,
+	.progress	= ignore_progress,
+};
+
+/**
+ * Null job control interface
+ *
+ * This is the interface to which job control interfaces are connected
+ * when unplugged.  It will never generate messages, and will silently
+ * absorb all received messages.
+ */
+struct job_interface null_job = {
+	.intf = {
+		.dest = &null_job.intf,
+		.refcnt = null_refcnt,
+	},
+	.op = &null_job_ops,
+};

src/include/gpxe/job.h

@@ -0,0 +1,124 @@
+#ifndef _GPXE_JOB_H
+#define _GPXE_JOB_H
+
+/** @file
+ *
+ * Job control interfaces
+ *
+ */
+
+#include <stddef.h>
+#include <gpxe/interface.h>
+
+/** Job progress */
+struct job_progress {
+	/** Amount of operation completed so far
+	 *
+	 * The units for this quantity are arbitrary.  @c completed
+	 * divded by @total should give something which approximately
+	 * represents the progress through the operation.  For a
+	 * download operation, using byte counts would make sense.
+	 */
+	unsigned long completed;
+	/** Total operation size
+	 *
+	 * See @c completed.  A zero value means "total size unknown"
+	 * and is explcitly permitted; users should take this into
+	 * account before calculating @c completed/total.
+	 */
+	unsigned long total;
+};
+
+struct job_interface;
+
+/** Job control interface operations */
+struct job_interface_operations {
+	/** Job completed
+	 *
+	 * @v job		Job control interface
+	 * @v rc		Overall job status code
+	 */
+	void ( * done ) ( struct job_interface *job, int rc );
+	/** Abort job
+	 *
+	 * @v job		Job control interface
+	 */
+	void ( * kill ) ( struct job_interface *job );
+	/** Get job progress
+	 *
+	 * @v job		Job control interface
+	 * @v progress		Progress data to fill in
+	 */
+	void ( * progress ) ( struct job_interface *job,
+			      struct job_progress *progress );
+};
+
+/** A job control interface */
+struct job_interface {
+	/** Generic object communication interface */
+	struct interface intf;
+	/** Operations for received messages */
+	struct job_interface_operations *op;
+};
+
+extern struct job_interface null_job;
+extern struct job_interface_operations null_job_ops;
+
+extern void done ( struct job_interface *job, int rc );
+
+extern void ignore_done ( struct job_interface *job, int rc );
+extern void ignore_kill ( struct job_interface *job );
+extern void ignore_progress ( struct job_interface *job,
+			      struct job_progress *progress );
+
+/**
+ * Initialise a job control interface
+ *
+ * @v job		Job control interface
+ * @v op		Job control interface operations
+ * @v refcnt		Job control interface reference counting method
+ */
+static inline void job_init ( struct job_interface *job,
+			       struct job_interface_operations *op,
+			       void ( * refcnt ) ( struct interface *intf,
+						   int delta ) ) {
+	job->intf.dest = &null_job.intf;
+	job->intf.refcnt = refcnt;
+	job->op = op;
+}
+
+/**
+ * Get job control interface from generic object communication interface
+ *
+ * @v intf		Generic object communication interface
+ * @ret job		Job control interface
+ */
+static inline struct job_interface *
+intf_to_job ( struct interface *intf ) {
+	return container_of ( intf, struct job_interface, intf );
+}
+
+/**
+ * Get destination job control interface
+ *
+ * @v job		Job control interface
+ * @ret dest		Destination interface
+ */
+static inline struct job_interface *
+job_dest ( struct job_interface *job ) {
+	return intf_to_job ( job->intf.dest );
+}
+
+/**
+ * Stop using a job control interface
+ *
+ * @v job		Job control interface
+ *
+ * After calling this method, no further messages will be received via
+ * the interface.
+ */
+static inline void job_nullify ( struct job_interface *job ) {
+	job->op = &null_job_ops;
+};
+
+#endif /* _GPXE_JOB_H */