[CRIU] [PATCH 05/11] pstree: add a function to check if a task is in pstree

[Qiang Huang]

Sometimes, when we parse some global info files, we can only care about
tasks which are taken into dump(such as file locks), which means their
pids are in the pstree.
So a function like this would be help.

Signed-off-by: Qiang Huang <h.huangqiang at huawei.com>
---
 include/pstree.h |    1 +
 pstree.c         |   12 ++++++++++++
 2 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/include/pstree.h b/include/pstree.h
index d13dacf..cefc750 100644
--- a/include/pstree.h
+++ b/include/pstree.h
@@ -58,6 +58,7 @@ extern bool restore_before_setsid(struct pstree_item *child);
 extern int prepare_pstree(void);
 
 extern int dump_pstree(struct pstree_item *root_item);
+extern bool pid_in_pstree(pid_t pid);
 
 struct task_entries;
 extern struct task_entries *task_entries;
diff --git a/pstree.c b/pstree.c
index 3ba645e..216f95d 100644
--- a/pstree.c
+++ b/pstree.c
@@ -455,3 +455,15 @@ bool restore_before_setsid(struct pstree_item *child)
 
 	return false;
 }
+
+bool pid_in_pstree(pid_t pid)
+{
+	struct pstree_item *item;
+
+	for_each_pstree_item(item) {
+		if (item->pid.real == pid)
+			return true;
+	}
+
+	return false;
+}
-- 
1.7.1