1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
  136
  137
  138

base / process / process_iterator_mac.cc [blame]

// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/process/process_iterator.h"

#include <errno.h>
#include <stddef.h>
#include <sys/sysctl.h>
#include <sys/types.h>
#include <unistd.h>

#include "base/logging.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"

namespace base {

ProcessIterator::ProcessIterator(const ProcessFilter* filter)
    : filter_(filter) {
  // Get a snapshot of all of my processes (yes, as we loop it can go stale, but
  // but trying to find where we were in a constantly changing list is basically
  // impossible.

  int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_UID,
                static_cast<int>(geteuid()) };

  // Since more processes could start between when we get the size and when
  // we get the list, we do a loop to keep trying until we get it.
  bool done = false;
  int try_num = 1;
  const int max_tries = 10;
  do {
    // Get the size of the buffer
    size_t len = 0;
    if (sysctl(mib, std::size(mib), NULL, &len, NULL, 0) < 0) {
      DLOG(ERROR) << "failed to get the size needed for the process list";
      kinfo_procs_.resize(0);
      done = true;
    } else {
      size_t num_of_kinfo_proc = len / sizeof(struct kinfo_proc);
      // Leave some spare room for process table growth (more could show up
      // between when we check and now)
      num_of_kinfo_proc += 16;
      kinfo_procs_.resize(num_of_kinfo_proc);
      len = num_of_kinfo_proc * sizeof(struct kinfo_proc);
      // Load the list of processes
      if (sysctl(mib, std::size(mib), &kinfo_procs_[0], &len, NULL, 0) < 0) {
        // If we get a mem error, it just means we need a bigger buffer, so
        // loop around again.  Anything else is a real error and give up.
        if (errno != ENOMEM) {
          DLOG(ERROR) << "failed to get the process list";
          kinfo_procs_.resize(0);
          done = true;
        }
      } else {
        // Got the list, just make sure we're sized exactly right
        kinfo_procs_.resize(len / sizeof(struct kinfo_proc));
        done = true;
      }
    }
  } while (!done && (try_num++ < max_tries));

  if (!done) {
    DLOG(ERROR) << "failed to collect the process list in a few tries";
    kinfo_procs_.resize(0);
  }
}

ProcessIterator::~ProcessIterator() = default;

bool ProcessIterator::CheckForNextProcess() {
  std::string data;
  for (; index_of_kinfo_proc_ < kinfo_procs_.size(); ++index_of_kinfo_proc_) {
    kinfo_proc& kinfo = kinfo_procs_[index_of_kinfo_proc_];

    // Skip processes just awaiting collection
    if ((kinfo.kp_proc.p_pid > 0) && (kinfo.kp_proc.p_stat == SZOMB))
      continue;

    int mib[] = { CTL_KERN, KERN_PROCARGS, kinfo.kp_proc.p_pid };

    // Find out what size buffer we need.
    size_t data_len = 0;
    if (sysctl(mib, std::size(mib), NULL, &data_len, NULL, 0) < 0) {
      DVPLOG(1) << "failed to figure out the buffer size for a commandline";
      continue;
    }

    data.resize(data_len);
    if (sysctl(mib, std::size(mib), &data[0], &data_len, NULL, 0) < 0) {
      DVPLOG(1) << "failed to fetch a commandline";
      continue;
    }

    // |data| contains all the command line parameters of the process, separated
    // by blocks of one or more null characters. We tokenize |data| into a
    // vector of strings using '\0' as a delimiter and populate
    // |entry_.cmd_line_args_|.
    std::string delimiters;
    delimiters.push_back('\0');
    entry_.cmd_line_args_ = SplitString(data, delimiters,
                                        KEEP_WHITESPACE, SPLIT_WANT_NONEMPTY);

    // |data| starts with the full executable path followed by a null character.
    // We search for the first instance of '\0' and extract everything before it
    // to populate |entry_.exe_file_|.
    size_t exec_name_end = data.find('\0');
    if (exec_name_end == std::string::npos) {
      DLOG(ERROR) << "command line data didn't match expected format";
      continue;
    }

    entry_.pid_ = kinfo.kp_proc.p_pid;
    entry_.ppid_ = kinfo.kp_eproc.e_ppid;
    entry_.gid_ = kinfo.kp_eproc.e_pgid;
    size_t last_slash = data.rfind('/', exec_name_end);
    if (last_slash == std::string::npos)
      entry_.exe_file_.assign(data, 0, exec_name_end);
    else
      entry_.exe_file_.assign(data, last_slash + 1,
                              exec_name_end - last_slash - 1);
    // Start w/ the next entry next time through
    ++index_of_kinfo_proc_;
    // Done
    return true;
  }
  return false;
}

bool NamedProcessIterator::IncludeEntry() {
  const bool name_match =
      use_prefix_match_ ? base::StartsWith(entry().exe_file(), executable_name_)
                        : executable_name_ == entry().exe_file();
  return name_match && ProcessIterator::IncludeEntry();
}

}  // namespace base