Add a method to Process to get uid for a pid.

Use the uids to track native processes. Cache the uids to avoid
checking /proc every time.

1 files changed, 15 insertions, 1 deletions

diff --git a/core/java/android/os/Process.java b/core/java/android/os/Process.java
index 333c7cb..1214abc 100644
--- a/core/java/android/os/Process.java
+++ b/core/java/android/os/Process.java
@@ -573,7 +573,21 @@ public class Process {
      * directly to a gid.
      */
     public static final native int getGidForName(String name);
-    
+
+    /**
+     * Returns a uid for a currently running process.
+     * @param pid the process id
+     * @return the uid of the process, or -1 if the process is not running.
+     * @hide pending API council review
+     */
+    public static final int getUidForPid(int pid) {
+        String[] procStatusLabels = { "Uid:" };
+        long[] procStatusValues = new long[1];
+        procStatusValues[0] = -1;
+        Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues);
+        return (int) procStatusValues[0];
+    }
+
     /**
      * Set the priority of a thread, based on Linux priorities.
      *