Mac: Implement about:memory.

chrome/browser/process_info_snapshot_mac.cc

+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/process_info_snapshot.h"
+
+#include <iostream>
+#include <sstream>
+
+#include "base/string_util.h"
+#include "base/thread.h"
+
+// Implementation for the Mac; calls '/bin/ps' for information when
+// |Sample()| is called.
+
+// Default constructor.
+ProcessInfoSnapshot::ProcessInfoSnapshot() { }
+
+// Destructor: just call |Reset()| to release everything.
+ProcessInfoSnapshot::~ProcessInfoSnapshot() {
+  Reset();
+}
+
+// Capture the information by calling '/bin/ps'.
+// Note: we ignore the "tsiz" (text size) display option of ps because it's
+// always zero (tested on 10.5 and 10.6).
+bool ProcessInfoSnapshot::Sample(std::vector<base::ProcessId> pid_list) {
+  Reset();
+
+  std::vector<std::string> argv;
+  argv.push_back("/bin/ps");
+  // Get PID, PPID, (real) UID, effective UID, resident set size, virtual memory
+  // size, and command.
+  argv.push_back("-o");
+  argv.push_back("pid=,ppid=,ruid=,uid=,rss=,vsz=,comm=");
+  // Only display the specified PIDs.
+  for(std::vector<base::ProcessId>::iterator it = pid_list.begin();
+      it != pid_list.end(); ++it) {
+    argv.push_back("-p");
+    argv.push_back(Int64ToString(static_cast<int64>(*it)));
+  }
+
+  std::string output;
+  CommandLine command_line(argv);
+  if (!base::GetAppOutputRestricted(command_line,
+                                    &output, (pid_list.size() + 10) * 100)) {
+    LOG(ERROR) << "Failure running /bin/ps to acquire data.";
+    return false;
+  }
+
+  std::istringstream in(output, std::istringstream::in);
+  std::string line;
+
+  // Process lines until done.
+  while (true) {
+    ProcInfoEntry proc_info;
+
+    // The format is as specified above to ps (see ps(1)):
+    //   "-o pid=,ppid=,ruid=,uid=,rss=,vsz=,comm=".
+    // Try to read the PID; if we get it, we should be able to get the rest of
+    // the line.
+    in >> proc_info.pid;
+    if (in.eof())
+      break;
+    in >> proc_info.ppid;
+    in >> proc_info.uid;
+    in >> proc_info.euid;
+    in >> proc_info.rss;
+    in >> proc_info.vsize;
+    in.ignore(1, ' ');                    // Eat the space.
+    std::getline(in, proc_info.command);  // Get the rest of the line.
+    if (!in.good()) {
+      LOG(ERROR) << "Error parsing output from /usr/bin/top.";
+      return false;
+    }
+
+    // Make sure the new PID isn't already in our list.
+    if (proc_info_entries_.find(proc_info.pid) != proc_info_entries_.end()) {
+      LOG(ERROR) << "Duplicate PID in output from /bin/ps.";
+      return false;
+    }
+
+    if (!proc_info.pid || ! proc_info.vsize) {
+      LOG(WARNING) << "Invalid data from /bin/ps.";
+      return false;
+    }
+
+    // Record the process information.
+    proc_info_entries_[proc_info.pid] = proc_info;
+  }
+
+  return true;
+}
+
+// Clear all the stored information.
+void ProcessInfoSnapshot::Reset() {
+  proc_info_entries_.clear();
+}
+
+bool ProcessInfoSnapshot::GetProcInfo(int pid,
+                                      ProcInfoEntry* proc_info) const {
+  std::map<int,ProcInfoEntry>::const_iterator it = proc_info_entries_.find(pid);
+  if (it == proc_info_entries_.end())
+    return false;
+
+  *proc_info = it->second;
+  return true;
+}
+
+bool ProcessInfoSnapshot::GetCommittedKBytesOfPID(
+    int pid,
+    base::CommittedKBytes* usage) const {
+  // Try to avoid crashing on a bug; stats aren't usually so crucial.
+  if (!usage) {
+    NOTREACHED();
+    return false;
+  }
+
+  // Failure of |GetProcInfo()| is "normal", due to racing.
+  ProcInfoEntry proc_info;
+  if (!GetProcInfo(pid, &proc_info)) {
+    usage->priv = 0;
+    usage->mapped = 0;
+    usage->image = 0;
+    return false;
+  }
+
+  usage->priv = proc_info.vsize;
+  usage->mapped = 0;
+  usage->image = 0;
+  return true;
+}
+
+bool ProcessInfoSnapshot::GetWorkingSetKBytesOfPID(
+    int pid,
+    base::WorkingSetKBytes* ws_usage) const {
+  // Try to avoid crashing on a bug; stats aren't usually so crucial.
+  if (!ws_usage) {
+    NOTREACHED();
+    return false;
+  }
+
+  // Failure of |GetProcInfo()| is "normal", due to racing.
+  ProcInfoEntry proc_info;
+  if (!GetProcInfo(pid, &proc_info)) {
+    ws_usage->priv = 0;
+    ws_usage->shareable = 0;
+    ws_usage->shared = 0;
+    return false;
+  }
+
+  ws_usage->priv = 0;
+  ws_usage->shareable = proc_info.rss;
+  ws_usage->shared = 0;
+  return true;
+}