[32/50] mesos git commit: Libprocess: Introduced Hooks for Subprocess.

[vi...@apache.org]

Libprocess: Introduced Hooks for Subprocess.

Review: https://reviews.apache.org/r/43302


Project: http://git-wip-us.apache.org/repos/asf/mesos/repo
Commit: http://git-wip-us.apache.org/repos/asf/mesos/commit/a450c474
Tree: http://git-wip-us.apache.org/repos/asf/mesos/tree/a450c474
Diff: http://git-wip-us.apache.org/repos/asf/mesos/diff/a450c474

Branch: refs/heads/0.26.x
Commit: a450c474dec7ed23cbf3835f3902d7cda4354ae8
Parents: dac9f4a
Author: Joris Van Remoortere <jo...@gmail.com>
Authored: Thu Feb 4 14:54:27 2016 -0500
Committer: Michael Park <mp...@apache.org>
Committed: Fri Feb 26 20:59:06 2016 -0800

----------------------------------------------------------------------
 .../libprocess/include/process/subprocess.hpp   | 27 ++++++++++++++++++++
 3rdparty/libprocess/src/subprocess.cpp          |  5 ++++
 2 files changed, 32 insertions(+)
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http://git-wip-us.apache.org/repos/asf/mesos/blob/a450c474/3rdparty/libprocess/include/process/subprocess.hpp
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diff --git a/3rdparty/libprocess/include/process/subprocess.hpp b/3rdparty/libprocess/include/process/subprocess.hpp
index f17816e..0932def 100644
--- a/3rdparty/libprocess/include/process/subprocess.hpp
+++ b/3rdparty/libprocess/include/process/subprocess.hpp
@@ -23,6 +23,7 @@
 
 #include <map>
 #include <memory>
+#include <mutex>
 #include <string>
 #include <vector>
 
@@ -124,6 +125,32 @@ public:
   }
 
   /**
+   * A hook can be passed to a `subprocess` call. It provides a way to
+   * inject dynamic implementation behavior between the clone and exec
+   * calls in the implementation of `subprocess`.
+   */
+  struct Hook
+  {
+    /**
+     * Returns an empty list of hooks.
+     */
+    static std::vector<Hook> None() { return std::vector<Hook>(); }
+
+    Hook(const lambda::function<Try<Nothing>(pid_t)>& _parent_callback);
+
+    /**
+     * The callback that must be sepcified for execution after the
+     * child has been cloned, but before it start executing the new
+     * process. This provides access to the child pid after its
+     * initialization to add tracking or modify execution state of
+     * the child before it executes the new process.
+     */
+    const lambda::function<Try<Nothing>(pid_t)> parent_callback;
+
+    friend class Subprocess;
+  };
+
+  /**
    * @return The operating system PID for this subprocess.
    */
   pid_t pid() const { return data->pid; }

http://git-wip-us.apache.org/repos/asf/mesos/blob/a450c474/3rdparty/libprocess/src/subprocess.cpp
----------------------------------------------------------------------
diff --git a/3rdparty/libprocess/src/subprocess.cpp b/3rdparty/libprocess/src/subprocess.cpp
index efe0018..3bf3a0b 100644
--- a/3rdparty/libprocess/src/subprocess.cpp
+++ b/3rdparty/libprocess/src/subprocess.cpp
@@ -39,6 +39,11 @@ using std::string;
 using std::vector;
 
 namespace process {
+
+Subprocess::Hook::Hook(
+    const lambda::function<Try<Nothing>(pid_t)>& _parent_callback)
+  : parent_callback(_parent_callback) {}
+
 namespace internal {
 
 // See the comment below as to why subprocess is passed to cleanup.