process_util.h revision 4a5e2dc747d50c653511c68ccb2cfbfb740bd5a7
1// Copyright (c) 2010 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// This file/namespace contains utility functions for enumerating, ending and
6// computing statistics of processes.
7
8#ifndef BASE_PROCESS_UTIL_H_
9#define BASE_PROCESS_UTIL_H_
10#pragma once
11
12#include "base/basictypes.h"
13
14#if defined(OS_WIN)
15#include <windows.h>
16#include <tlhelp32.h>
17#elif defined(OS_MACOSX)
18// kinfo_proc is defined in <sys/sysctl.h>, but this forward declaration
19// is sufficient for the vector<kinfo_proc> below.
20struct kinfo_proc;
21// malloc_zone_t is defined in <malloc/malloc.h>, but this forward declaration
22// is sufficient for GetPurgeableZone() below.
23typedef struct _malloc_zone_t malloc_zone_t;
24#include <mach/mach.h>
25#elif defined(OS_POSIX)
26#include <dirent.h>
27#include <limits.h>
28#include <sys/types.h>
29#endif
30
31#include <list>
32#include <string>
33#include <utility>
34#include <vector>
35
36#include "base/file_descriptor_shuffle.h"
37#include "base/process.h"
38
39class CommandLine;
40class FilePath;
41
42namespace base {
43
44#if defined(OS_WIN)
45struct ProcessEntry : public PROCESSENTRY32 {
46  ProcessId pid() const { return th32ProcessID; }
47  ProcessId parent_pid() const { return th32ParentProcessID; }
48  const wchar_t* exe_file() const { return szExeFile; }
49};
50
51struct IoCounters : public IO_COUNTERS {
52};
53
54// Process access masks. These constants provide platform-independent
55// definitions for the standard Windows access masks.
56// See http://msdn.microsoft.com/en-us/library/ms684880(VS.85).aspx for
57// the specific semantics of each mask value.
58const uint32 kProcessAccessTerminate              = PROCESS_TERMINATE;
59const uint32 kProcessAccessCreateThread           = PROCESS_CREATE_THREAD;
60const uint32 kProcessAccessSetSessionId           = PROCESS_SET_SESSIONID;
61const uint32 kProcessAccessVMOperation            = PROCESS_VM_OPERATION;
62const uint32 kProcessAccessVMRead                 = PROCESS_VM_READ;
63const uint32 kProcessAccessVMWrite                = PROCESS_VM_WRITE;
64const uint32 kProcessAccessDuplicateHandle        = PROCESS_DUP_HANDLE;
65const uint32 kProcessAccessCreateProcess          = PROCESS_CREATE_PROCESS;
66const uint32 kProcessAccessSetQuota               = PROCESS_SET_QUOTA;
67const uint32 kProcessAccessSetInformation         = PROCESS_SET_INFORMATION;
68const uint32 kProcessAccessQueryInformation       = PROCESS_QUERY_INFORMATION;
69const uint32 kProcessAccessSuspendResume          = PROCESS_SUSPEND_RESUME;
70const uint32 kProcessAccessQueryLimitedInfomation =
71    PROCESS_QUERY_LIMITED_INFORMATION;
72const uint32 kProcessAccessWaitForTermination     = SYNCHRONIZE;
73#elif defined(OS_POSIX)
74
75struct ProcessEntry {
76  ProcessEntry();
77  ~ProcessEntry();
78
79  ProcessId pid_;
80  ProcessId ppid_;
81  ProcessId gid_;
82  std::string exe_file_;
83  std::vector<std::string> cmd_line_args_;
84
85  ProcessId pid() const { return pid_; }
86  ProcessId parent_pid() const { return ppid_; }
87  ProcessId gid() const { return gid_; }
88  const char* exe_file() const { return exe_file_.c_str(); }
89  const std::vector<std::string>& cmd_line_args() const {
90    return cmd_line_args_;
91  }
92};
93
94struct IoCounters {
95  uint64_t ReadOperationCount;
96  uint64_t WriteOperationCount;
97  uint64_t OtherOperationCount;
98  uint64_t ReadTransferCount;
99  uint64_t WriteTransferCount;
100  uint64_t OtherTransferCount;
101};
102
103// Process access masks. They are not used on Posix because access checking
104// does not happen during handle creation.
105const uint32 kProcessAccessTerminate              = 0;
106const uint32 kProcessAccessCreateThread           = 0;
107const uint32 kProcessAccessSetSessionId           = 0;
108const uint32 kProcessAccessVMOperation            = 0;
109const uint32 kProcessAccessVMRead                 = 0;
110const uint32 kProcessAccessVMWrite                = 0;
111const uint32 kProcessAccessDuplicateHandle        = 0;
112const uint32 kProcessAccessCreateProcess          = 0;
113const uint32 kProcessAccessSetQuota               = 0;
114const uint32 kProcessAccessSetInformation         = 0;
115const uint32 kProcessAccessQueryInformation       = 0;
116const uint32 kProcessAccessSuspendResume          = 0;
117const uint32 kProcessAccessQueryLimitedInfomation = 0;
118const uint32 kProcessAccessWaitForTermination     = 0;
119#endif  // defined(OS_POSIX)
120
121// A minimalistic but hopefully cross-platform set of exit codes.
122// Do not change the enumeration values or you will break third-party
123// installers.
124enum {
125  PROCESS_END_NORMAL_TERMINATION = 0,
126  PROCESS_END_KILLED_BY_USER     = 1,
127  PROCESS_END_PROCESS_WAS_HUNG   = 2
128};
129
130// Returns the id of the current process.
131ProcessId GetCurrentProcId();
132
133// Returns the ProcessHandle of the current process.
134ProcessHandle GetCurrentProcessHandle();
135
136// Converts a PID to a process handle. This handle must be closed by
137// CloseProcessHandle when you are done with it. Returns true on success.
138bool OpenProcessHandle(ProcessId pid, ProcessHandle* handle);
139
140// Converts a PID to a process handle. On Windows the handle is opened
141// with more access rights and must only be used by trusted code.
142// You have to close returned handle using CloseProcessHandle. Returns true
143// on success.
144// TODO(sanjeevr): Replace all calls to OpenPrivilegedProcessHandle with the
145// more specific OpenProcessHandleWithAccess method and delete this.
146bool OpenPrivilegedProcessHandle(ProcessId pid, ProcessHandle* handle);
147
148// Converts a PID to a process handle using the desired access flags. Use a
149// combination of the kProcessAccess* flags defined above for |access_flags|.
150bool OpenProcessHandleWithAccess(ProcessId pid,
151                                 uint32 access_flags,
152                                 ProcessHandle* handle);
153
154// Closes the process handle opened by OpenProcessHandle.
155void CloseProcessHandle(ProcessHandle process);
156
157// Returns the unique ID for the specified process. This is functionally the
158// same as Windows' GetProcessId(), but works on versions of Windows before
159// Win XP SP1 as well.
160ProcessId GetProcId(ProcessHandle process);
161
162#if defined(OS_LINUX)
163// Returns the ID for the parent of the given process.
164ProcessId GetParentProcessId(ProcessHandle process);
165
166// Returns the path to the executable of the given process.
167FilePath GetProcessExecutablePath(ProcessHandle process);
168
169// Parse the data found in /proc/<pid>/stat and return the sum of the
170// CPU-related ticks.  Returns -1 on parse error.
171// Exposed for testing.
172int ParseProcStatCPU(const std::string& input);
173
174static const char kAdjustOOMScoreSwitch[] = "--adjust-oom-score";
175
176// This adjusts /proc/process/oom_adj so the Linux OOM killer will prefer
177// certain process types over others. The range for the adjustment is
178// [-17,15], with [0,15] being user accessible.
179bool AdjustOOMScore(ProcessId process, int score);
180#endif
181
182#if defined(OS_POSIX)
183// Close all file descriptors, expect those which are a destination in the
184// given multimap. Only call this function in a child process where you know
185// that there aren't any other threads.
186void CloseSuperfluousFds(const InjectiveMultimap& saved_map);
187#endif
188
189#if defined(OS_WIN)
190
191enum IntegrityLevel {
192  INTEGRITY_UNKNOWN,
193  LOW_INTEGRITY,
194  MEDIUM_INTEGRITY,
195  HIGH_INTEGRITY,
196};
197// Determine the integrity level of the specified process. Returns false
198// if the system does not support integrity levels (pre-Vista) or in the case
199// of an underlying system failure.
200bool GetProcessIntegrityLevel(ProcessHandle process, IntegrityLevel *level);
201
202// Runs the given application name with the given command line. Normally, the
203// first command line argument should be the path to the process, and don't
204// forget to quote it.
205//
206// If wait is true, it will block and wait for the other process to finish,
207// otherwise, it will just continue asynchronously.
208//
209// Example (including literal quotes)
210//  cmdline = "c:\windows\explorer.exe" -foo "c:\bar\"
211//
212// If process_handle is non-NULL, the process handle of the launched app will be
213// stored there on a successful launch.
214// NOTE: In this case, the caller is responsible for closing the handle so
215//       that it doesn't leak!
216bool LaunchApp(const std::wstring& cmdline,
217               bool wait, bool start_hidden, ProcessHandle* process_handle);
218
219// Same as LaunchApp, except allows the new process to inherit handles of the
220// parent process.
221bool LaunchAppWithHandleInheritance(const std::wstring& cmdline,
222                                    bool wait,
223                                    bool start_hidden,
224                                    ProcessHandle* process_handle);
225
226// Runs the given application name with the given command line as if the user
227// represented by |token| had launched it. The caveats about |cmdline| and
228// |process_handle| explained for LaunchApp above apply as well.
229//
230// Whether the application is visible on the interactive desktop depends on
231// the token belonging to an interactive logon session.
232//
233// To avoid hard to diagnose problems, this function internally loads the
234// environment variables associated with the user and if this operation fails
235// the entire call fails as well.
236bool LaunchAppAsUser(UserTokenHandle token, const std::wstring& cmdline,
237                     bool start_hidden, ProcessHandle* process_handle);
238
239// Has the same behavior as LaunchAppAsUser, but offers the boolean option to
240// use an empty string for the desktop name and a boolean for allowing the
241// child process to inherit handles from its parent.
242bool LaunchAppAsUser(UserTokenHandle token, const std::wstring& cmdline,
243                     bool start_hidden, ProcessHandle* process_handle,
244                     bool empty_desktop_name, bool inherit_handles);
245
246
247#elif defined(OS_POSIX)
248// Runs the application specified in argv[0] with the command line argv.
249// Before launching all FDs open in the parent process will be marked as
250// close-on-exec.  |fds_to_remap| defines a mapping of src fd->dest fd to
251// propagate FDs into the child process.
252//
253// As above, if wait is true, execute synchronously. The pid will be stored
254// in process_handle if that pointer is non-null.
255//
256// Note that the first argument in argv must point to the executable filename.
257// If the filename is not fully specified, PATH will be searched.
258typedef std::vector<std::pair<int, int> > file_handle_mapping_vector;
259bool LaunchApp(const std::vector<std::string>& argv,
260               const file_handle_mapping_vector& fds_to_remap,
261               bool wait, ProcessHandle* process_handle);
262
263// Similar to the above, but also (un)set environment variables in child process
264// through |environ|.
265typedef std::vector<std::pair<std::string, std::string> > environment_vector;
266bool LaunchApp(const std::vector<std::string>& argv,
267               const environment_vector& environ,
268               const file_handle_mapping_vector& fds_to_remap,
269               bool wait, ProcessHandle* process_handle);
270
271// Similar to the above two methods, but starts the child process in a process
272// group of its own, instead of allowing it to inherit the parent's process
273// group. The pgid of the child process will be the same as its pid.
274bool LaunchAppInNewProcessGroup(const std::vector<std::string>& argv,
275                                const environment_vector& environ,
276                                const file_handle_mapping_vector& fds_to_remap,
277                                bool wait, ProcessHandle* process_handle);
278
279// AlterEnvironment returns a modified environment vector, constructed from the
280// given environment and the list of changes given in |changes|. Each key in
281// the environment is matched against the first element of the pairs. In the
282// event of a match, the value is replaced by the second of the pair, unless
283// the second is empty, in which case the key-value is removed.
284//
285// The returned array is allocated using new[] and must be freed by the caller.
286char** AlterEnvironment(const environment_vector& changes,
287                        const char* const* const env);
288#endif  // defined(OS_POSIX)
289
290// Executes the application specified by cl. This function delegates to one
291// of the above two platform-specific functions.
292bool LaunchApp(const CommandLine& cl,
293               bool wait, bool start_hidden, ProcessHandle* process_handle);
294
295// Executes the application specified by |cl| and wait for it to exit. Stores
296// the output (stdout) in |output|. Redirects stderr to /dev/null. Returns true
297// on success (application launched and exited cleanly, with exit code
298// indicating success).
299bool GetAppOutput(const CommandLine& cl, std::string* output);
300
301#if defined(OS_POSIX)
302// A restricted version of |GetAppOutput()| which (a) clears the environment,
303// and (b) stores at most |max_output| bytes; also, it doesn't search the path
304// for the command.
305bool GetAppOutputRestricted(const CommandLine& cl,
306                            std::string* output, size_t max_output);
307#endif
308
309// Used to filter processes by process ID.
310class ProcessFilter {
311 public:
312  // Returns true to indicate set-inclusion and false otherwise.  This method
313  // should not have side-effects and should be idempotent.
314  virtual bool Includes(const ProcessEntry& entry) const = 0;
315
316 protected:
317  virtual ~ProcessFilter() {}
318};
319
320// Returns the number of processes on the machine that are running from the
321// given executable name.  If filter is non-null, then only processes selected
322// by the filter will be counted.
323int GetProcessCount(const std::wstring& executable_name,
324                    const ProcessFilter* filter);
325
326// Attempts to kill all the processes on the current machine that were launched
327// from the given executable name, ending them with the given exit code.  If
328// filter is non-null, then only processes selected by the filter are killed.
329// Returns true if all processes were able to be killed off, false if at least
330// one couldn't be killed.
331bool KillProcesses(const std::wstring& executable_name, int exit_code,
332                   const ProcessFilter* filter);
333
334// Attempts to kill the process identified by the given process
335// entry structure, giving it the specified exit code. If |wait| is true, wait
336// for the process to be actually terminated before returning.
337// Returns true if this is successful, false otherwise.
338bool KillProcess(ProcessHandle process, int exit_code, bool wait);
339
340#if defined(OS_POSIX)
341// Attempts to kill the process group identified by |process_group_id|. Returns
342// true on success.
343bool KillProcessGroup(ProcessHandle process_group_id);
344#endif
345
346#if defined(OS_WIN)
347bool KillProcessById(ProcessId process_id, int exit_code, bool wait);
348#endif
349
350// Get the termination status (exit code) of the process and return true if the
351// status indicates the process crashed. |child_exited| is set to true iff the
352// child process has terminated. (|child_exited| may be NULL.)
353bool DidProcessCrash(bool* child_exited, ProcessHandle handle);
354
355// Waits for process to exit. In POSIX systems, if the process hasn't been
356// signaled then puts the exit code in |exit_code|; otherwise it's considered
357// a failure. On Windows |exit_code| is always filled. Returns true on success,
358// and closes |handle| in any case.
359bool WaitForExitCode(ProcessHandle handle, int* exit_code);
360
361// Waits for process to exit. If it did exit within |timeout_milliseconds|,
362// then puts the exit code in |exit_code|, closes |handle|, and returns true.
363// In POSIX systems, if the process has been signaled then |exit_code| is set
364// to -1. Returns false on failure (the caller is then responsible for closing
365// |handle|).
366bool WaitForExitCodeWithTimeout(ProcessHandle handle, int* exit_code,
367                                int64 timeout_milliseconds);
368
369// Wait for all the processes based on the named executable to exit.  If filter
370// is non-null, then only processes selected by the filter are waited on.
371// Returns after all processes have exited or wait_milliseconds have expired.
372// Returns true if all the processes exited, false otherwise.
373bool WaitForProcessesToExit(const std::wstring& executable_name,
374                            int64 wait_milliseconds,
375                            const ProcessFilter* filter);
376
377// Wait for a single process to exit. Return true if it exited cleanly within
378// the given time limit.
379bool WaitForSingleProcess(ProcessHandle handle,
380                          int64 wait_milliseconds);
381
382// Returns true when |wait_milliseconds| have elapsed and the process
383// is still running.
384bool CrashAwareSleep(ProcessHandle handle, int64 wait_milliseconds);
385
386// Waits a certain amount of time (can be 0) for all the processes with a given
387// executable name to exit, then kills off any of them that are still around.
388// If filter is non-null, then only processes selected by the filter are waited
389// on.  Killed processes are ended with the given exit code.  Returns false if
390// any processes needed to be killed, true if they all exited cleanly within
391// the wait_milliseconds delay.
392bool CleanupProcesses(const std::wstring& executable_name,
393                      int64 wait_milliseconds,
394                      int exit_code,
395                      const ProcessFilter* filter);
396
397// This class provides a way to iterate through a list of processes on the
398// current machine with a specified filter.
399// To use, create an instance and then call NextProcessEntry() until it returns
400// false.
401class ProcessIterator {
402 public:
403  typedef std::list<ProcessEntry> ProcessEntries;
404
405  explicit ProcessIterator(const ProcessFilter* filter);
406  virtual ~ProcessIterator();
407
408  // If there's another process that matches the given executable name,
409  // returns a const pointer to the corresponding PROCESSENTRY32.
410  // If there are no more matching processes, returns NULL.
411  // The returned pointer will remain valid until NextProcessEntry()
412  // is called again or this NamedProcessIterator goes out of scope.
413  const ProcessEntry* NextProcessEntry();
414
415  // Takes a snapshot of all the ProcessEntry found.
416  ProcessEntries Snapshot();
417
418 protected:
419  virtual bool IncludeEntry();
420  const ProcessEntry& entry() { return entry_; }
421
422 private:
423  // Determines whether there's another process (regardless of executable)
424  // left in the list of all processes.  Returns true and sets entry_ to
425  // that process's info if there is one, false otherwise.
426  bool CheckForNextProcess();
427
428  // Initializes a PROCESSENTRY32 data structure so that it's ready for
429  // use with Process32First/Process32Next.
430  void InitProcessEntry(ProcessEntry* entry);
431
432#if defined(OS_WIN)
433  HANDLE snapshot_;
434  bool started_iteration_;
435#elif defined(OS_MACOSX)
436  std::vector<kinfo_proc> kinfo_procs_;
437  size_t index_of_kinfo_proc_;
438#elif defined(OS_POSIX)
439  DIR *procfs_dir_;
440#endif
441  ProcessEntry entry_;
442  const ProcessFilter* filter_;
443
444  DISALLOW_COPY_AND_ASSIGN(ProcessIterator);
445};
446
447// This class provides a way to iterate through the list of processes
448// on the current machine that were started from the given executable
449// name.  To use, create an instance and then call NextProcessEntry()
450// until it returns false.
451class NamedProcessIterator : public ProcessIterator {
452 public:
453  NamedProcessIterator(const std::wstring& executable_name,
454                       const ProcessFilter* filter);
455  virtual ~NamedProcessIterator();
456
457 protected:
458  virtual bool IncludeEntry();
459
460 private:
461  std::wstring executable_name_;
462
463  DISALLOW_COPY_AND_ASSIGN(NamedProcessIterator);
464};
465
466// Working Set (resident) memory usage broken down by
467//
468// On Windows:
469// priv (private): These pages (kbytes) cannot be shared with any other process.
470// shareable:      These pages (kbytes) can be shared with other processes under
471//                 the right circumstances.
472// shared :        These pages (kbytes) are currently shared with at least one
473//                 other process.
474//
475// On Linux:
476// priv:           Pages mapped only by this process
477// shared:         PSS or 0 if the kernel doesn't support this
478// shareable:      0
479//
480// On OS X: TODO(thakis): Revise.
481// priv:           Memory.
482// shared:         0
483// shareable:      0
484struct WorkingSetKBytes {
485  WorkingSetKBytes() : priv(0), shareable(0), shared(0) {}
486  size_t priv;
487  size_t shareable;
488  size_t shared;
489};
490
491// Committed (resident + paged) memory usage broken down by
492// private: These pages cannot be shared with any other process.
493// mapped:  These pages are mapped into the view of a section (backed by
494//          pagefile.sys)
495// image:   These pages are mapped into the view of an image section (backed by
496//          file system)
497struct CommittedKBytes {
498  CommittedKBytes() : priv(0), mapped(0), image(0) {}
499  size_t priv;
500  size_t mapped;
501  size_t image;
502};
503
504// Free memory (Megabytes marked as free) in the 2G process address space.
505// total : total amount in megabytes marked as free. Maximum value is 2048.
506// largest : size of the largest contiguous amount of memory found. It is
507//   always smaller or equal to FreeMBytes::total.
508// largest_ptr: starting address of the largest memory block.
509struct FreeMBytes {
510  size_t total;
511  size_t largest;
512  void* largest_ptr;
513};
514
515// Convert a POSIX timeval to microseconds.
516int64 TimeValToMicroseconds(const struct timeval& tv);
517
518// Provides performance metrics for a specified process (CPU usage, memory and
519// IO counters). To use it, invoke CreateProcessMetrics() to get an instance
520// for a specific process, then access the information with the different get
521// methods.
522class ProcessMetrics {
523 public:
524  // Creates a ProcessMetrics for the specified process.
525  // The caller owns the returned object.
526#if !defined(OS_MACOSX)
527  static ProcessMetrics* CreateProcessMetrics(ProcessHandle process);
528#else
529  class PortProvider {
530   public:
531    // Should return the mach task for |process| if possible, or else
532    // |MACH_PORT_NULL|. Only processes that this returns tasks for will have
533    // metrics on OS X (except for the current process, which always gets
534    // metrics).
535    virtual mach_port_t TaskForPid(ProcessHandle process) const = 0;
536  };
537
538  // The port provider needs to outlive the ProcessMetrics object returned by
539  // this function. If NULL is passed as provider, the returned object
540  // only returns valid metrics if |process| is the current process.
541  static ProcessMetrics* CreateProcessMetrics(ProcessHandle process,
542                                              PortProvider* port_provider);
543#endif  // !defined(OS_MACOSX)
544
545  ~ProcessMetrics();
546
547  // Returns the current space allocated for the pagefile, in bytes (these pages
548  // may or may not be in memory).  On Linux, this returns the total virtual
549  // memory size.
550  size_t GetPagefileUsage() const;
551  // Returns the peak space allocated for the pagefile, in bytes.
552  size_t GetPeakPagefileUsage() const;
553  // Returns the current working set size, in bytes.  On Linux, this returns
554  // the resident set size.
555  size_t GetWorkingSetSize() const;
556  // Returns the peak working set size, in bytes.
557  size_t GetPeakWorkingSetSize() const;
558  // Returns private and sharedusage, in bytes. Private bytes is the amount of
559  // memory currently allocated to a process that cannot be shared. Returns
560  // false on platform specific error conditions.  Note: |private_bytes|
561  // returns 0 on unsupported OSes: prior to XP SP2.
562  bool GetMemoryBytes(size_t* private_bytes,
563                      size_t* shared_bytes);
564  // Fills a CommittedKBytes with both resident and paged
565  // memory usage as per definition of CommittedBytes.
566  void GetCommittedKBytes(CommittedKBytes* usage) const;
567  // Fills a WorkingSetKBytes containing resident private and shared memory
568  // usage in bytes, as per definition of WorkingSetBytes.
569  bool GetWorkingSetKBytes(WorkingSetKBytes* ws_usage) const;
570
571  // Computes the current process available memory for allocation.
572  // It does a linear scan of the address space querying each memory region
573  // for its free (unallocated) status. It is useful for estimating the memory
574  // load and fragmentation.
575  bool CalculateFreeMemory(FreeMBytes* free) const;
576
577  // Returns the CPU usage in percent since the last time this method was
578  // called. The first time this method is called it returns 0 and will return
579  // the actual CPU info on subsequent calls.
580  // On Windows, the CPU usage value is for all CPUs. So if you have 2 CPUs and
581  // your process is using all the cycles of 1 CPU and not the other CPU, this
582  // method returns 50.
583  double GetCPUUsage();
584
585  // Retrieves accounting information for all I/O operations performed by the
586  // process.
587  // If IO information is retrieved successfully, the function returns true
588  // and fills in the IO_COUNTERS passed in. The function returns false
589  // otherwise.
590  bool GetIOCounters(IoCounters* io_counters) const;
591
592 private:
593#if !defined(OS_MACOSX)
594  explicit ProcessMetrics(ProcessHandle process);
595#else
596  ProcessMetrics(ProcessHandle process, PortProvider* port_provider);
597#endif  // !defined(OS_MACOSX)
598
599  ProcessHandle process_;
600
601  int processor_count_;
602
603  // Used to store the previous times and CPU usage counts so we can
604  // compute the CPU usage between calls.
605  int64 last_time_;
606  int64 last_system_time_;
607
608#if defined(OS_MACOSX)
609  // Queries the port provider if it's set.
610  mach_port_t TaskForPid(ProcessHandle process) const;
611
612  PortProvider* port_provider_;
613#elif defined(OS_POSIX)
614  // Jiffie count at the last_time_ we updated.
615  int last_cpu_;
616#endif  // defined(OS_MACOSX)
617
618  DISALLOW_COPY_AND_ASSIGN(ProcessMetrics);
619};
620
621// Returns the memory commited by the system in KBytes.
622// Returns 0 if it can't compute the commit charge.
623size_t GetSystemCommitCharge();
624
625// Enables low fragmentation heap (LFH) for every heaps of this process. This
626// won't have any effect on heaps created after this function call. It will not
627// modify data allocated in the heaps before calling this function. So it is
628// better to call this function early in initialization and again before
629// entering the main loop.
630// Note: Returns true on Windows 2000 without doing anything.
631bool EnableLowFragmentationHeap();
632
633// Enables 'terminate on heap corruption' flag. Helps protect against heap
634// overflow. Has no effect if the OS doesn't provide the necessary facility.
635void EnableTerminationOnHeapCorruption();
636
637#if !defined(OS_WIN)
638// Turns on process termination if memory runs out. This is handled on Windows
639// inside RegisterInvalidParamHandler().
640void EnableTerminationOnOutOfMemory();
641#if defined(OS_MACOSX)
642// Exposed for testing.
643malloc_zone_t* GetPurgeableZone();
644#endif
645#endif
646
647#if defined(UNIT_TEST)
648// Enables stack dump to console output on exception and signals.
649// When enabled, the process will quit immediately. This is meant to be used in
650// unit_tests only!
651bool EnableInProcessStackDumping();
652#endif  // defined(UNIT_TEST)
653
654// If supported on the platform, and the user has sufficent rights, increase
655// the current process's scheduling priority to a high priority.
656void RaiseProcessToHighPriority();
657
658#if defined(OS_MACOSX)
659// Restore the default exception handler, setting it to Apple Crash Reporter
660// (ReportCrash).  When forking and execing a new process, the child will
661// inherit the parent's exception ports, which may be set to the Breakpad
662// instance running inside the parent.  The parent's Breakpad instance should
663// not handle the child's exceptions.  Calling RestoreDefaultExceptionHandler
664// in the child after forking will restore the standard exception handler.
665// See http://crbug.com/20371/ for more details.
666void RestoreDefaultExceptionHandler();
667#endif  // defined(OS_MACOSX)
668
669}  // namespace base
670
671#endif  // BASE_PROCESS_UTIL_H_
672