commit 3eec5b9bee837e8a5454682902978ecfe5c1866d
author Steven Moreland <smoreland@google.com> Tue Jul 21 17:47:32 2020 +0000
committer Steven Moreland <smoreland@google.com> Fri Jul 24 17:38:11 2020 +0000
tree e3c3bbf680a570950f707b5b3f9777d09bdd23a5
parent afebef48e1e035a06770a1f67a0ccc644ff119d5

tryRegistrationImpl: better error checking

ifstream is_open does not check for errors, so we use ifstream operator
bool instead, and we use it more frequently than strictly needed. Also,
the functions here are added to attribute noinline, so that stacktraces
will be more useful.

Test: boot and check names are fixed up in `ps -A -o comm`
Bug: 161271113

Change-Id: Ia451fa1b06c49def0fe8b3a3558af83fff18ec96
Merged-In: Ia451fa1b06c49def0fe8b3a3558af83fff18ec96

transport/ServiceManagement.cpp

diff --git a/transport/ServiceManagement.cpp b/transport/ServiceManagement.cpp
index d7faa6d..7de5c78 100644
--- a/transport/ServiceManagement.cpp
+++ b/transport/ServiceManagement.cpp
@@ -87,7 +87,7 @@
 static std::string binaryName() {
     std::ifstream ifs("/proc/self/cmdline");
     std::string cmdline;
-    if (!ifs.is_open()) {
+    if (!ifs) {
         return "";
     }
     ifs >> cmdline;
@@ -106,7 +106,7 @@
     return packageAndVersion.substr(0, at);
 }
 
-static void tryShortenProcessName(const std::string& descriptor) {
+__attribute__((noinline)) static void tryShortenProcessName(const std::string& descriptor) {
     const static std::string kTasks = "/proc/self/task/";
 
     // make sure that this binary name is in the same package
@@ -135,17 +135,17 @@
         if (dp->d_name[0] == '.') continue;
 
         std::fstream fs(kTasks + dp->d_name + "/comm");
-        if (!fs.is_open()) {
+        if (!fs) {
             ALOGI("Could not rename process, failed read comm for %s.", dp->d_name);
             continue;
         }
 
         std::string oldComm;
-        fs >> oldComm;
+        if (!(fs >> oldComm)) continue;
 
         // don't rename if it already has an explicit name
         if (base::StartsWith(descriptor, oldComm)) {
-            fs.seekg(0, fs.beg);
+            if (!fs.seekg(0, fs.beg)) continue;
             fs << newName;
         }
     }
@@ -157,7 +157,7 @@
  * Returns the age of the current process by reading /proc/self/stat and comparing starttime to the
  * current time. This is useful for measuring how long it took a HAL to register itself.
  */
-static long getProcessAgeMs() {
+__attribute__((noinline)) static long getProcessAgeMs() {
     constexpr const int PROCFS_STAT_STARTTIME_INDEX = 21;
     std::string content;
     android::base::ReadFileToString("/proc/self/stat", &content, false);