src/basic/process-util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2010 Lennart Poettering
   8
   9   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <alloca.h>
  24 #include <errno.h>
  25 #include <sched.h>
  26 #include <signal.h>
  27 #include <stdbool.h>
  28 #include <stddef.h>
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <sys/resource.h>
  32 #include <sys/types.h>
  33
  34 #include "format-util.h"
  35 #include "ioprio.h"
  36 #include "macro.h"
  37 #include "time-util.h"
  38
  39 #define procfs_file_alloca(pid, field)                                  \
  40         ({                                                              \
  41                 pid_t _pid_ = (pid);                                    \
  42                 const char *_r_;                                        \
  43                 if (_pid_ == 0) {                                       \
  44                         _r_ = ("/proc/self/" field);                    \
  45                 } else {                                                \
  46                         _r_ = alloca(STRLEN("/proc/") + DECIMAL_STR_MAX(pid_t) + 1 + sizeof(field)); \
  47                         sprintf((char*) _r_, "/proc/"PID_FMT"/" field, _pid_);                       \
  48                 }                                                       \
  49                 _r_;                                                    \
  50         })
  51
  52 int get_process_state(pid_t pid);
  53 int get_process_comm(pid_t pid, char **name);
  54 int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line);
  55 int get_process_exe(pid_t pid, char **name);
  56 int get_process_uid(pid_t pid, uid_t *uid);
  57 int get_process_gid(pid_t pid, gid_t *gid);
  58 int get_process_capeff(pid_t pid, char **capeff);
  59 int get_process_cwd(pid_t pid, char **cwd);
  60 int get_process_root(pid_t pid, char **root);
  61 int get_process_environ(pid_t pid, char **environ);
  62 int get_process_ppid(pid_t pid, pid_t *ppid);
  63
  64 int wait_for_terminate(pid_t pid, siginfo_t *status);
  65
  66 typedef enum WaitFlags {
  67         WAIT_LOG_ABNORMAL             = 1U << 0,
  68         WAIT_LOG_NON_ZERO_EXIT_STATUS = 1U << 1,
  69
  70         /* A shortcut for requesting the most complete logging */
  71         WAIT_LOG = WAIT_LOG_ABNORMAL|WAIT_LOG_NON_ZERO_EXIT_STATUS,
  72 } WaitFlags;
  73
  74 int wait_for_terminate_and_check(const char *name, pid_t pid, WaitFlags flags);
  75 int wait_for_terminate_with_timeout(pid_t pid, usec_t timeout);
  76
  77 void sigkill_wait(pid_t pid);
  78 void sigkill_waitp(pid_t *pid);
  79
  80 int kill_and_sigcont(pid_t pid, int sig);
  81
  82 int rename_process(const char name[]);
  83 int is_kernel_thread(pid_t pid);
  84
  85 int getenv_for_pid(pid_t pid, const char *field, char **_value);
  86
  87 bool pid_is_alive(pid_t pid);
  88 bool pid_is_unwaited(pid_t pid);
  89 int pid_from_same_root_fs(pid_t pid);
  90
  91 bool is_main_thread(void);
  92
  93 noreturn void freeze(void);
  94
  95 bool oom_score_adjust_is_valid(int oa);
  96
  97 #ifndef PERSONALITY_INVALID
  98 /* personality(7) documents that 0xffffffffUL is used for querying the
  99  * current personality, hence let's use that here as error
 100  * indicator. */
 101 #define PERSONALITY_INVALID 0xffffffffLU
 102 #endif
 103
 104 unsigned long personality_from_string(const char *p);
 105 const char *personality_to_string(unsigned long);
 106
 107 int safe_personality(unsigned long p);
 108 int opinionated_personality(unsigned long *ret);
 109
 110 int ioprio_class_to_string_alloc(int i, char **s);
 111 int ioprio_class_from_string(const char *s);
 112
 113 const char *sigchld_code_to_string(int i) _const_;
 114 int sigchld_code_from_string(const char *s) _pure_;
 115
 116 int sched_policy_to_string_alloc(int i, char **s);
 117 int sched_policy_from_string(const char *s);
 118
 119 static inline pid_t PTR_TO_PID(const void *p) {
 120         return (pid_t) ((uintptr_t) p);
 121 }
 122
 123 static inline void* PID_TO_PTR(pid_t pid) {
 124         return (void*) ((uintptr_t) pid);
 125 }
 126
 127 void valgrind_summary_hack(void);
 128
 129 int pid_compare_func(const void *a, const void *b);
 130
 131 static inline bool nice_is_valid(int n) {
 132         return n >= PRIO_MIN && n < PRIO_MAX;
 133 }
 134
 135 static inline bool sched_policy_is_valid(int i) {
 136         return IN_SET(i, SCHED_OTHER, SCHED_BATCH, SCHED_IDLE, SCHED_FIFO, SCHED_RR);
 137 }
 138
 139 static inline bool sched_priority_is_valid(int i) {
 140         return i >= 0 && i <= sched_get_priority_max(SCHED_RR);
 141 }
 142
 143 static inline bool ioprio_class_is_valid(int i) {
 144         return IN_SET(i, IOPRIO_CLASS_NONE, IOPRIO_CLASS_RT, IOPRIO_CLASS_BE, IOPRIO_CLASS_IDLE);
 145 }
 146
 147 static inline bool ioprio_priority_is_valid(int i) {
 148         return i >= 0 && i < IOPRIO_BE_NR;
 149 }
 150
 151 static inline bool pid_is_valid(pid_t p) {
 152         return p > 0;
 153 }
 154
 155 static inline int sched_policy_to_string_alloc_with_check(int n, char **s) {
 156         if (!sched_policy_is_valid(n))
 157                 return -EINVAL;
 158
 159         return sched_policy_to_string_alloc(n, s);
 160 }
 161
 162 int ioprio_parse_priority(const char *s, int *ret);
 163
 164 pid_t getpid_cached(void);
 165 void reset_cached_pid(void);
 166
 167 int must_be_root(void);
 168
 169 typedef enum ForkFlags {
 170         FORK_RESET_SIGNALS = 1U << 0,
 171         FORK_CLOSE_ALL_FDS = 1U << 1,
 172         FORK_DEATHSIG      = 1U << 2,
 173         FORK_NULL_STDIO    = 1U << 3,
 174         FORK_REOPEN_LOG    = 1U << 4,
 175         FORK_LOG           = 1U << 5,
 176         FORK_WAIT          = 1U << 6,
 177         FORK_NEW_MOUNTNS   = 1U << 7,
 178 } ForkFlags;
 179
 180 int safe_fork_full(const char *name, const int except_fds[], size_t n_except_fds, ForkFlags flags, pid_t *ret_pid);
 181
 182 static inline int safe_fork(const char *name, ForkFlags flags, pid_t *ret_pid) {
 183         return safe_fork_full(name, NULL, 0, flags, ret_pid);
 184 }
 185
 186 int fork_agent(const char *name, const int except[], unsigned n_except, pid_t *pid, const char *path, ...);