[lxc-devel] [PATCH 2/3] execute: bind init.lxc.static into container

[Serge Hallyn]

Signed-off-by: Serge Hallyn <serge.hallyn at ubuntu.com>
---
 src/lxc/conf.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 7427a94..0580f46 100644
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -3811,6 +3811,61 @@ static void remount_all_slave(void)
 		free(line);
 }
 
+void lxc_execute_bind_init(struct lxc_conf *conf)
+{
+	int ret;
+	char path[PATH_MAX], destpath[PATH_MAX];
+
+	ret = snprintf(path, PATH_MAX, SBINDIR "/init.lxc.static");
+	if (ret < 0 || ret >= PATH_MAX) {
+		WARN("Path name too long searching for lxc.init.static");
+		return;
+	}
+
+	if (!file_exists(path)) {
+		INFO("%s does not exist on host", path);
+		return;
+	}
+
+	ret = snprintf(destpath, PATH_MAX, "%s%s", conf->rootfs.mount, path);
+	if (ret < 0 || ret >= PATH_MAX) {
+		WARN("Path name too long for container's lxc.init.static");
+		return;
+	}
+
+	if (!file_exists(destpath)) {
+		FILE *pathfile;
+		char *pathdirname = strdup(path);
+
+		if (!pathdirname) {
+			SYSERROR("Out of memory binding lxc.init.static into container");
+			return;
+		}
+		pathdirname = dirname(pathdirname);
+		ret = mkdir_p(pathdirname, 0755);
+		free(pathdirname);
+		if (ret < 0) {
+			/*
+			 * this can fail just due to read-only bind mounts.  Trust
+			 * that the user knows what they want, log and proceed
+			 */
+			WARN("Failed to create %s in container", SBINDIR);
+			return;
+		}
+		pathfile = fopen(destpath, "wb");
+		if (!pathfile) {
+			SYSERROR("Failed to create mount target '%s'", destpath);
+			return;
+		}
+		fclose(pathfile);
+	}
+
+	ret = mount(path, destpath, "none", MS_BIND, NULL);
+	if (ret < 0)
+		SYSERROR("Failed to bind lxc.init.static into container");
+	INFO("lxc.init.static bound into container at %s", path);
+}
+
 int lxc_setup(struct lxc_handler *handler)
 {
 	const char *name = handler->name;
@@ -3878,6 +3933,9 @@ int lxc_setup(struct lxc_handler *handler)
 		return -1;
 	}
 
+	if (lxc_conf->is_execute)
+		lxc_execute_bind_init(lxc_conf);
+
 	/* now mount only cgroup, if wanted;
 	 * before, /sys could not have been mounted
 	 * (is either mounted automatically or via fstab entries)
-- 
1.9.1