init: introduce ro.kernel.version property
This property will hold the major.minor part of the kernel version (e.g. "5.4"), allowing init scripts to act depending on that version, enabling and disabling certain features.
Bug: 194156700
Change-Id: Icec640b8a7150b344d9aa3bc0bdbcdae050c7c45
Test: manual on a Pixel device
Signed-off-by: Alexander Potapenko <glider@google.com>
diff --git a/init/init.cpp b/init/init.cpp
index bde8e04..e3596cb 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -27,6 +27,7 @@
#include <sys/mount.h>
#include <sys/signalfd.h>
#include <sys/types.h>
+#include <sys/utsname.h>
#include <unistd.h>
#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
@@ -554,6 +555,19 @@
}
}
+/// Set ro.kernel.version property to contain the major.minor pair as returned
+/// by uname(2).
+static void SetKernelVersion() {
+ struct utsname uts;
+ unsigned int major, minor;
+
+ if ((uname(&uts) != 0) || (sscanf(uts.release, "%u.%u", &major, &minor) != 2)) {
+ LOG(ERROR) << "Could not parse the kernel version from uname";
+ return;
+ }
+ SetProperty("ro.kernel.version", android::base::StringPrintf("%u.%u", major, minor));
+}
+
static void HandleSigtermSignal(const signalfd_siginfo& siginfo) {
if (siginfo.ssi_pid != 0) {
// Drop any userspace SIGTERM requests.
@@ -858,6 +872,7 @@
export_oem_lock_status();
MountHandler mount_handler(&epoll);
SetUsbController();
+ SetKernelVersion();
const BuiltinFunctionMap& function_map = GetBuiltinFunctionMap();
Action::set_function_map(&function_map);