From 9fedb3b40b5983372b2c2de29dfe321c6dfaadf4 Mon Sep 17 00:00:00 2001
From: William Hubbs <w.d.hubbs@gmail.com>
Date: Tue, 1 Dec 2015 18:20:02 -0600
Subject: [PATCH] Add detection for docker containers

---
 etc/rc.conf.Linux | 1 +
 man/openrc-run.8  | 2 ++
 src/librc/librc.c | 4 ++++
 src/librc/rc.h.in | 1 +
 4 files changed, 8 insertions(+)

diff --git a/etc/rc.conf.Linux b/etc/rc.conf.Linux
index f04f96ef..0865075b 100644
--- a/etc/rc.conf.Linux
+++ b/etc/rc.conf.Linux
@@ -3,6 +3,7 @@
 
 # This is the subsystem type. Valid options on Linux:
 # ""               - nothing special
+# "docker"         - Docker container manager
 # "lxc"            - Linux Containers
 # "openvz"         - Linux OpenVZ
 # "prefix"         - Prefix
diff --git a/man/openrc-run.8 b/man/openrc-run.8
index 12c1919b..9e0e7763 100644
--- a/man/openrc-run.8
+++ b/man/openrc-run.8
@@ -223,6 +223,8 @@ Same as -jail, but for VServer systems.
 Same as -jail, but for Xen DOM0 systems.
 .It Dv -xenu
 Same as -jail, but for Xen DOMU systems.
+.It Dv -docker
+Same as -jail, but for docker systems.
 .El
 .El
 .Pp
diff --git a/src/librc/librc.c b/src/librc/librc.c
index 5e5de8d8..cad80333 100644
--- a/src/librc/librc.c
+++ b/src/librc/librc.c
@@ -269,6 +269,8 @@ rc_sys(void)
 			return RC_SYS_LXC;
 		if (strcmp(systype, RC_SYS_SYSTEMD_NSPAWN) == 0)
 				return RC_SYS_SYSTEMD_NSPAWN;
+		if (strcmp(systype, RC_SYS_DOCKER) == 0)
+				return RC_SYS_DOCKER;
 	}
 	if (exists("/proc/xen")) {
 		if (file_regex("/proc/xen/capabilities", "control_d"))
@@ -288,6 +290,8 @@ rc_sys(void)
 		return RC_SYS_LXC;
 	else if (file_regex("/proc/1/environ", "container=systemd-nspawn"))
 		return RC_SYS_SYSTEMD_NSPAWN;
+	else if (file_regex("/proc/1/environ", "container=docker"))
+		return RC_SYS_DOCKER;
 #endif
 
 	return NULL;
diff --git a/src/librc/rc.h.in b/src/librc/rc.h.in
index 141ecb97..360c26a1 100644
--- a/src/librc/rc.h.in
+++ b/src/librc/rc.h.in
@@ -329,6 +329,7 @@ bool rc_service_daemons_crashed(const char *);
 /*! @name System types
  * OpenRC can support some special sub system types, normally virtualization.
  * Some services cannot work in these systems, or we do something else. */
+#define RC_SYS_DOCKER  "DOCKER"
 #define RC_SYS_JAIL    "JAIL"
 #define RC_SYS_OPENVZ  "OPENVZ"
 #define RC_SYS_LXC     "LXC"