From d1e048f95618b6fb7f66c81e1c650482d95cd452 Mon Sep 17 00:00:00 2001
From: "T.J. Mercier" <tjmercier@google.com>
Date: Thu, 28 Mar 2024 00:33:44 +0000
Subject: [PATCH] Use ConvertUid{Pid}ToPath for all path generation

Consolidate into a single implementation.

Test: m
Change-Id: I0fc52db2d4b2973a74bad24c0a5f77384a559cee
---
 libprocessgroup/processgroup.cpp  |  8 --------
 libprocessgroup/task_profiles.cpp | 18 ++++++++++++++----
 libprocessgroup/task_profiles.h   |  3 +++
 3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index 94d950209..8df2805d9 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -78,14 +78,6 @@ bool CgroupGetControllerPath(const std::string& cgroup_name, std::string* path)
     return true;
 }
 
-static std::string ConvertUidToPath(const char* cgroup, uid_t uid) {
-    return StringPrintf("%s/uid_%u", cgroup, uid);
-}
-
-static std::string ConvertUidPidToPath(const char* cgroup, uid_t uid, pid_t pid) {
-    return StringPrintf("%s/uid_%u/pid_%d", cgroup, uid, pid);
-}
-
 static bool CgroupKillAvailable() {
     static std::once_flag f;
     static bool cgroup_kill_available = false;
diff --git a/libprocessgroup/task_profiles.cpp b/libprocessgroup/task_profiles.cpp
index 2353cf18a..c376a0fe6 100644
--- a/libprocessgroup/task_profiles.cpp
+++ b/libprocessgroup/task_profiles.cpp
@@ -126,11 +126,19 @@ void ProfileAttribute::Reset(const CgroupController& controller, const std::stri
     file_v2_name_ = file_v2_name;
 }
 
+std::string ConvertUidToPath(const char* root_cgroup_path, uid_t uid) {
+    return StringPrintf("%s/uid_%u", root_cgroup_path, uid);
+}
+
+std::string ConvertUidPidToPath(const char* root_cgroup_path, uid_t uid, pid_t pid) {
+    const std::string uid_path = ConvertUidToPath(root_cgroup_path, uid);
+    return StringPrintf("%s/pid_%d", uid_path.c_str(), pid);
+}
+
 bool ProfileAttribute::GetPathForProcess(uid_t uid, pid_t pid, std::string* path) const {
     if (controller()->version() == 2) {
-        // all cgroup v2 attributes use the same process group hierarchy
-        *path = StringPrintf("%s/uid_%u/pid_%d/%s", controller()->path(), uid, pid,
-                             file_name().c_str());
+        const std::string cgroup_path = ConvertUidPidToPath(controller()->path(), uid, pid);
+        *path = cgroup_path + "/" + file_name();
         return true;
     }
     return GetPathForTask(pid, path);
@@ -155,12 +163,14 @@ bool ProfileAttribute::GetPathForTask(pid_t tid, std::string* path) const {
     return true;
 }
 
+// NOTE: This function is for cgroup v2 only
 bool ProfileAttribute::GetPathForUID(uid_t uid, std::string* path) const {
     if (path == nullptr) {
         return true;
     }
 
-    *path = StringPrintf("%s/uid_%u/%s", controller()->path(), uid, file_name().c_str());
+    const std::string cgroup_path = ConvertUidToPath(controller()->path(), uid);
+    *path = cgroup_path + "/" + file_name();
     return true;
 }
 
diff --git a/libprocessgroup/task_profiles.h b/libprocessgroup/task_profiles.h
index 428447106..7e3c50d9f 100644
--- a/libprocessgroup/task_profiles.h
+++ b/libprocessgroup/task_profiles.h
@@ -252,3 +252,6 @@ class TaskProfiles {
     std::map<std::string, std::shared_ptr<TaskProfile>, std::less<>> profiles_;
     std::map<std::string, std::unique_ptr<IProfileAttribute>, std::less<>> attributes_;
 };
+
+std::string ConvertUidToPath(const char* root_cgroup_path, uid_t uid);
+std::string ConvertUidPidToPath(const char* root_cgroup_path, uid_t uid, pid_t pid);