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 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 68 ProcessIterator::~ProcessIterator() { 69 } 70 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 } 128 129 bool NamedProcessIterator::IncludeEntry() { 130 return (executable_name_ == entry().exe_file() && 131 ProcessIterator::IncludeEntry()); 132 } 133 134 } // namespace base 135