Parse /proc/<pid>/stats fields as int64

Some entries are 64 bits wide, and will overflow on occasion.  In particular,
VM_STARTTIME will overflow a 32-bit int on long-running systems.

BUG=332491
TEST=local build, run on desktop Linux

Review URL: https://codereview.chromium.org/129353002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243733 0039d316-1c4b-4281-b951-d872f2087c98

base/process/internal_linux.cc

@@ -115,13 +115,13 @@ void ParseProcStat(const std::string& contents, ProcStatMap* output) {
   }
 }
 
-int GetProcStatsFieldAsInt(const std::vector<std::string>& proc_stats,
+int64 GetProcStatsFieldAsInt64(const std::vector<std::string>& proc_stats,
                                ProcStatsFields field_num) {
   DCHECK_GE(field_num, VM_PPID);
   CHECK_LT(static_cast<size_t>(field_num), proc_stats.size());
 
-  int value;
-  return StringToInt(proc_stats[field_num], &value) ? value : 0;
+  int64 value;
+  return StringToInt64(proc_stats[field_num], &value) ? value : 0;
 }
 
 size_t GetProcStatsFieldAsSizeT(const std::vector<std::string>& proc_stats,
@@ -133,15 +133,14 @@ size_t GetProcStatsFieldAsSizeT(const std::vector<std::string>& proc_stats,
   return StringToSizeT(proc_stats[field_num], &value) ? value : 0;
 }
 
-int ReadProcStatsAndGetFieldAsInt(pid_t pid,
-                                  ProcStatsFields field_num) {
+int64 ReadProcStatsAndGetFieldAsInt64(pid_t pid, ProcStatsFields field_num) {
   std::string stats_data;
   if (!ReadProcStats(pid, &stats_data))
     return 0;
   std::vector<std::string> proc_stats;
   if (!ParseProcStats(stats_data, &proc_stats))
     return 0;
-  return GetProcStatsFieldAsInt(proc_stats, field_num);
+  return GetProcStatsFieldAsInt64(proc_stats, field_num);
 }
 
 size_t ReadProcStatsAndGetFieldAsSizeT(pid_t pid,

base/process/internal_linux.h

@@ -63,19 +63,18 @@ enum ProcStatsFields {
 // Reads the |field_num|th field from |proc_stats|. Returns 0 on failure.
 // This version does not handle the first 3 values, since the first value is
 // simply |pid|, and the next two values are strings.
-int GetProcStatsFieldAsInt(const std::vector<std::string>& proc_stats,
+int64 GetProcStatsFieldAsInt64(const std::vector<std::string>& proc_stats,
                                ProcStatsFields field_num);
 
-// Same as GetProcStatsFieldAsInt(), but for size_t values.
+// Same as GetProcStatsFieldAsInt64(), but for size_t values.
 size_t GetProcStatsFieldAsSizeT(const std::vector<std::string>& proc_stats,
                                 ProcStatsFields field_num);
 
-// Convenience wrapper around GetProcStatsFieldAsInt(), ParseProcStats() and
-// ReadProcStats(). See GetProcStatsFieldAsInt() for details.
-int ReadProcStatsAndGetFieldAsInt(pid_t pid,
-                                  ProcStatsFields field_num);
+// Convenience wrapper around GetProcStatsFieldAsInt64(), ParseProcStats() and
+// ReadProcStats(). See GetProcStatsFieldAsInt64() for details.
+int64 ReadProcStatsAndGetFieldAsInt64(pid_t pid, ProcStatsFields field_num);
 
-// Same as ReadProcStatsAndGetFieldAsInt() but for size_t values.
+// Same as ReadProcStatsAndGetFieldAsInt64() but for size_t values.
 size_t ReadProcStatsAndGetFieldAsSizeT(pid_t pid,
                                        ProcStatsFields field_num);
 

base/process/process_handle_linux.cc

@@ -11,7 +11,7 @@ namespace base {
 
 ProcessId GetParentProcessId(ProcessHandle process) {
   ProcessId pid =
-      internal::ReadProcStatsAndGetFieldAsInt(process, internal::VM_PPID);
+      internal::ReadProcStatsAndGetFieldAsInt64(process, internal::VM_PPID);
   if (pid)
     return pid;
   return -1;

base/process/process_info_linux.cc

@@ -15,8 +15,8 @@ namespace base {
 //static
 const Time CurrentProcessInfo::CreationTime() {
   ProcessHandle pid = GetCurrentProcessHandle();
-  int start_ticks = internal::ReadProcStatsAndGetFieldAsInt(
-      pid, internal::VM_STARTTIME);
+  int64 start_ticks =
+      internal::ReadProcStatsAndGetFieldAsInt64(pid, internal::VM_STARTTIME);
   DCHECK(start_ticks);
   TimeDelta start_offset = internal::ClockTicksToTimeDelta(start_ticks);
   Time boot_time = internal::GetBootTime();

base/process/process_iterator_linux.cc

@@ -121,8 +121,8 @@ bool ProcessIterator::CheckForNextProcess() {
   }
 
   entry_.pid_ = pid;
-  entry_.ppid_ = GetProcStatsFieldAsInt(proc_stats, internal::VM_PPID);
-  entry_.gid_ = GetProcStatsFieldAsInt(proc_stats, internal::VM_PGRP);
+  entry_.ppid_ = GetProcStatsFieldAsInt64(proc_stats, internal::VM_PPID);
+  entry_.gid_ = GetProcStatsFieldAsInt64(proc_stats, internal::VM_PGRP);
   entry_.cmd_line_args_.assign(cmd_line_args.begin(), cmd_line_args.end());
   entry_.exe_file_ = GetProcessExecutablePath(pid).BaseName().value();
   return true;

base/process/process_metrics_linux.cc

@@ -391,15 +391,15 @@ int ParseProcStatCPU(const std::string& input) {
 
   if (proc_stats.size() <= internal::VM_STIME)
     return -1;
-  int utime = GetProcStatsFieldAsInt(proc_stats, internal::VM_UTIME);
-  int stime = GetProcStatsFieldAsInt(proc_stats, internal::VM_STIME);
+  int utime = GetProcStatsFieldAsInt64(proc_stats, internal::VM_UTIME);
+  int stime = GetProcStatsFieldAsInt64(proc_stats, internal::VM_STIME);
   return utime + stime;
 }
 
 const char kProcSelfExe[] = "/proc/self/exe";
 
 int GetNumberOfThreads(ProcessHandle process) {
-  return internal::ReadProcStatsAndGetFieldAsInt(process,
+  return internal::ReadProcStatsAndGetFieldAsInt64(process,
                                                    internal::VM_NUMTHREADS);
 }