1 // Copyright (c) 2013 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 #include "base/process/process_iterator.h"
6
7 #include <errno.h>
8 #include <sys/sysctl.h>
9 #include <sys/types.h>
10
11 #include "base/logging.h"
12 #include "base/strings/string_util.h"
13
14 namespace base {
15
ProcessIterator(const ProcessFilter * filter)16 ProcessIterator::ProcessIterator(const ProcessFilter* filter)
17 : index_of_kinfo_proc_(0),
18 filter_(filter) {
19 // Get a snapshot of all of my processes (yes, as we loop it can go stale, but
20 // but trying to find where we were in a constantly changing list is basically
21 // impossible.
22
23 int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_UID, geteuid() };
24
25 // Since more processes could start between when we get the size and when
26 // we get the list, we do a loop to keep trying until we get it.
27 bool done = false;
28 int try_num = 1;
29 const int max_tries = 10;
30 do {
31 // Get the size of the buffer
32 size_t len = 0;
33 if (sysctl(mib, arraysize(mib), NULL, &len, NULL, 0) < 0) {
34 DLOG(ERROR) << "failed to get the size needed for the process list";
35 kinfo_procs_.resize(0);
36 done = true;
37 } else {
38 size_t num_of_kinfo_proc = len / sizeof(struct kinfo_proc);
39 // Leave some spare room for process table growth (more could show up
40 // between when we check and now)
41 num_of_kinfo_proc += 16;
42 kinfo_procs_.resize(num_of_kinfo_proc);
43 len = num_of_kinfo_proc * sizeof(struct kinfo_proc);
44 // Load the list of processes
45 if (sysctl(mib, arraysize(mib), &kinfo_procs_[0], &len, NULL, 0) < 0) {
46 // If we get a mem error, it just means we need a bigger buffer, so
47 // loop around again. Anything else is a real error and give up.
48 if (errno != ENOMEM) {
49 DLOG(ERROR) << "failed to get the process list";
50 kinfo_procs_.resize(0);
51 done = true;
52 }
53 } else {
54 // Got the list, just make sure we're sized exactly right
55 size_t num_of_kinfo_proc = len / sizeof(struct kinfo_proc);
56 kinfo_procs_.resize(num_of_kinfo_proc);
57 done = true;
58 }
59 }
60 } while (!done && (try_num++ < max_tries));
61
62 if (!done) {
63 DLOG(ERROR) << "failed to collect the process list in a few tries";
64 kinfo_procs_.resize(0);
65 }
66 }
67
~ProcessIterator()68 ProcessIterator::~ProcessIterator() {
69 }
70
CheckForNextProcess()71 bool ProcessIterator::CheckForNextProcess() {
72 std::string data;
73 for (; index_of_kinfo_proc_ < kinfo_procs_.size(); ++index_of_kinfo_proc_) {
74 kinfo_proc& kinfo = kinfo_procs_[index_of_kinfo_proc_];
75
76 // Skip processes just awaiting collection
77 if ((kinfo.kp_proc.p_pid > 0) && (kinfo.kp_proc.p_stat == SZOMB))
78 continue;
79
80 int mib[] = { CTL_KERN, KERN_PROCARGS, kinfo.kp_proc.p_pid };
81
82 // Find out what size buffer we need.
83 size_t data_len = 0;
84 if (sysctl(mib, arraysize(mib), NULL, &data_len, NULL, 0) < 0) {
85 DVPLOG(1) << "failed to figure out the buffer size for a commandline";
86 continue;
87 }
88
89 data.resize(data_len);
90 if (sysctl(mib, arraysize(mib), &data[0], &data_len, NULL, 0) < 0) {
91 DVPLOG(1) << "failed to fetch a commandline";
92 continue;
93 }
94
95 // |data| contains all the command line parameters of the process, separated
96 // by blocks of one or more null characters. We tokenize |data| into a
97 // vector of strings using '\0' as a delimiter and populate
98 // |entry_.cmd_line_args_|.
99 std::string delimiters;
100 delimiters.push_back('\0');
101 Tokenize(data, delimiters, &entry_.cmd_line_args_);
102
103 // |data| starts with the full executable path followed by a null character.
104 // We search for the first instance of '\0' and extract everything before it
105 // to populate |entry_.exe_file_|.
106 size_t exec_name_end = data.find('\0');
107 if (exec_name_end == std::string::npos) {
108 DLOG(ERROR) << "command line data didn't match expected format";
109 continue;
110 }
111
112 entry_.pid_ = kinfo.kp_proc.p_pid;
113 entry_.ppid_ = kinfo.kp_eproc.e_ppid;
114 entry_.gid_ = kinfo.kp_eproc.e_pgid;
115 size_t last_slash = data.rfind('/', exec_name_end);
116 if (last_slash == std::string::npos)
117 entry_.exe_file_.assign(data, 0, exec_name_end);
118 else
119 entry_.exe_file_.assign(data, last_slash + 1,
120 exec_name_end - last_slash - 1);
121 // Start w/ the next entry next time through
122 ++index_of_kinfo_proc_;
123 // Done
124 return true;
125 }
126 return false;
127 }
128
IncludeEntry()129 bool NamedProcessIterator::IncludeEntry() {
130 return (executable_name_ == entry().exe_file() &&
131 ProcessIterator::IncludeEntry());
132 }
133
134 } // namespace base
135