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-rw-r--r--debian/grub-extras/disabled/gpxe/src/core/process.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/debian/grub-extras/disabled/gpxe/src/core/process.c b/debian/grub-extras/disabled/gpxe/src/core/process.c
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index 0000000..9c13e02
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+++ b/debian/grub-extras/disabled/gpxe/src/core/process.c
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2006 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.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <gpxe/list.h>
+#include <gpxe/init.h>
+#include <gpxe/process.h>
+
+/** @file
+ *
+ * Processes
+ *
+ * We implement a trivial form of cooperative multitasking, in which
+ * all processes share a single stack and address space.
+ */
+
+/** Process run queue */
+static LIST_HEAD ( run_queue );
+
+/**
+ * Add process to process list
+ *
+ * @v process Process
+ *
+ * It is safe to call process_add() multiple times; further calls will
+ * have no effect.
+ */
+void process_add ( struct process *process ) {
+ if ( list_empty ( &process->list ) ) {
+ DBGC ( process, "PROCESS %p starting\n", process );
+ ref_get ( process->refcnt );
+ list_add_tail ( &process->list, &run_queue );
+ } else {
+ DBGC ( process, "PROCESS %p already started\n", process );
+ }
+}
+
+/**
+ * Remove process from process list
+ *
+ * @v process Process
+ *
+ * It is safe to call process_del() multiple times; further calls will
+ * have no effect.
+ */
+void process_del ( struct process *process ) {
+ if ( ! list_empty ( &process->list ) ) {
+ DBGC ( process, "PROCESS %p stopping\n", process );
+ list_del ( &process->list );
+ INIT_LIST_HEAD ( &process->list );
+ ref_put ( process->refcnt );
+ } else {
+ DBGC ( process, "PROCESS %p already stopped\n", process );
+ }
+}
+
+/**
+ * Single-step a single process
+ *
+ * This executes a single step of the first process in the run queue,
+ * and moves the process to the end of the run queue.
+ */
+void step ( void ) {
+ struct process *process;
+
+ list_for_each_entry ( process, &run_queue, list ) {
+ list_del ( &process->list );
+ list_add_tail ( &process->list, &run_queue );
+ DBGC2 ( process, "PROCESS %p executing\n", process );
+ process->step ( process );
+ DBGC2 ( process, "PROCESS %p finished executing\n", process );
+ break;
+ }
+}
+
+/**
+ * Initialise processes
+ *
+ */
+static void init_processes ( void ) {
+ struct process *process;
+
+ for_each_table_entry ( process, PERMANENT_PROCESSES )
+ process_add ( process );
+}
+
+/** Process initialiser */
+struct init_fn process_init_fn __init_fn ( INIT_NORMAL ) = {
+ .initialise = init_processes,
+};