conntrackd: add child process infrastructure

This patch adds a simple infrastructure that allows to account
the child processes that have been forked. This also includes
a callback handler that can be registered that is called once
the child process finishes.

We can extended this later to include an alarm to limit the
maximum lifetime of a forked child process. This is good to
ensure that child processes behave timely.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 55 insertions, 0 deletions

diff --git a/src/process.c b/src/process.c
new file mode 100644
index 0000000..a89f388
--- /dev/null
+++ b/src/process.c
@@ -0,0 +1,55 @@
+/*
+ * (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org>
+ * 
+ * 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
+ * (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, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "conntrackd.h"
+#include "process.h"
+
+static LIST_HEAD(process_list);
+
+int fork_process_new(void (*cb)(void *data), void *data)
+{
+	struct child_process *c;
+
+	c = calloc(sizeof(struct child_process), 1);
+	if (c == NULL)
+		return -1;
+
+	c->cb = cb;
+	c->data = data;
+
+	list_add(&c->head, &process_list);
+
+	return fork();
+}
+
+int fork_process_delete(int pid)
+{
+	struct child_process *this, *tmp;
+
+	list_for_each_entry_safe(this, tmp, &process_list, head) {
+		if (this->pid == pid) {
+			list_del(&this->head);
+			if (this->cb) {
+				this->cb(this->data);
+			}
+			free(this);
+			return 1;
+		}
+	}
+	return 0;
+}