Adding guardrails on writing to disk from statsd

- Limit total number of files to 1000
- Limit total size of files to 5MB
- Remove idle files to be deleted after 30 days

Bug: 69854160
Test: manual testing, statsd, statsd_test
Change-Id: I33148a3b7ca11d413ec2495d5c0659f1ba4485c3
diff --git a/cmds/statsd/src/config/ConfigManager.cpp b/cmds/statsd/src/config/ConfigManager.cpp
index 42994b5..15af7c5 100644
--- a/cmds/statsd/src/config/ConfigManager.cpp
+++ b/cmds/statsd/src/config/ConfigManager.cpp
@@ -185,8 +185,8 @@
     remove_saved_configs(key);
 
     // Then we save the latest config.
-    string file_name = StringPrintf("%s/%d-%lld-%ld", STATS_SERVICE_DIR, key.GetUid(),
-                                    (long long)key.GetId(), time(nullptr));
+    string file_name = StringPrintf("%s/%ld_%d_%lld", STATS_SERVICE_DIR, time(nullptr),
+                                    key.GetUid(), (long long)key.GetId());
     const int numBytes = config.ByteSize();
     vector<uint8_t> buffer(numBytes);
     config.SerializeToArray(&buffer[0], numBytes);