1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 #pragma once
3 
4 #include <errno.h>
5 #include <sched.h>
6 #include <signal.h>
7 #include <stdbool.h>
8 #include <stddef.h>
9 #include <stdio.h>
10 #include <string.h>
11 #include <sys/resource.h>
12 #include <sys/types.h>
13 
14 #include "alloc-util.h"
15 #include "format-util.h"
16 #include "macro.h"
17 #include "time-util.h"
18 
19 #define procfs_file_alloca(pid, field)                                  \
20         ({                                                              \
21                 pid_t _pid_ = (pid);                                    \
22                 const char *_field_ = (field);                          \
23                 char *_r_;                                              \
24                 if (_pid_ == 0) {                                       \
25                         _r_ = newa(char, STRLEN("/proc/self/") + strlen(_field_) + 1); \
26                         strcpy(stpcpy(_r_, "/proc/self/"), _field_);    \
27                 } else {                                                \
28                         _r_ = newa(char, STRLEN("/proc/") + DECIMAL_STR_MAX(pid_t) + 1 + strlen(_field_) + 1); \
29                         sprintf(_r_, "/proc/" PID_FMT "/%s", _pid_, _field_); \
30                 }                                                       \
31                 (const char*) _r_;                                      \
32         })
33 
34 typedef enum ProcessCmdlineFlags {
35         PROCESS_CMDLINE_COMM_FALLBACK = 1 << 0,
36         PROCESS_CMDLINE_USE_LOCALE    = 1 << 1,
37         PROCESS_CMDLINE_QUOTE         = 1 << 2,
38         PROCESS_CMDLINE_QUOTE_POSIX   = 1 << 3,
39 } ProcessCmdlineFlags;
40 
41 int get_process_comm(pid_t pid, char **ret);
42 int get_process_cmdline(pid_t pid, size_t max_columns, ProcessCmdlineFlags flags, char **ret);
43 int get_process_exe(pid_t pid, char **ret);
44 int get_process_uid(pid_t pid, uid_t *ret);
45 int get_process_gid(pid_t pid, gid_t *ret);
46 int get_process_capeff(pid_t pid, char **ret);
47 int get_process_cwd(pid_t pid, char **ret);
48 int get_process_root(pid_t pid, char **ret);
49 int get_process_environ(pid_t pid, char **ret);
50 int get_process_ppid(pid_t pid, pid_t *ret);
51 int get_process_umask(pid_t pid, mode_t *ret);
52 
53 int wait_for_terminate(pid_t pid, siginfo_t *status);
54 
55 typedef enum WaitFlags {
56         WAIT_LOG_ABNORMAL             = 1 << 0,
57         WAIT_LOG_NON_ZERO_EXIT_STATUS = 1 << 1,
58 
59         /* A shortcut for requesting the most complete logging */
60         WAIT_LOG = WAIT_LOG_ABNORMAL|WAIT_LOG_NON_ZERO_EXIT_STATUS,
61 } WaitFlags;
62 
63 int wait_for_terminate_and_check(const char *name, pid_t pid, WaitFlags flags);
64 int wait_for_terminate_with_timeout(pid_t pid, usec_t timeout);
65 
66 void sigkill_wait(pid_t pid);
67 void sigkill_waitp(pid_t *pid);
68 void sigterm_wait(pid_t pid);
69 
70 int kill_and_sigcont(pid_t pid, int sig);
71 
72 int rename_process(const char name[]);
73 int is_kernel_thread(pid_t pid);
74 
75 int getenv_for_pid(pid_t pid, const char *field, char **_value);
76 
77 bool pid_is_alive(pid_t pid);
78 bool pid_is_unwaited(pid_t pid);
79 int pid_is_my_child(pid_t pid);
80 int pid_from_same_root_fs(pid_t pid);
81 
82 bool is_main_thread(void);
83 
84 bool oom_score_adjust_is_valid(int oa);
85 
86 #ifndef PERSONALITY_INVALID
87 /* personality(7) documents that 0xffffffffUL is used for querying the
88  * current personality, hence let's use that here as error
89  * indicator. */
90 #define PERSONALITY_INVALID 0xffffffffLU
91 #endif
92 
93 unsigned long personality_from_string(const char *p);
94 const char *personality_to_string(unsigned long);
95 
96 int safe_personality(unsigned long p);
97 int opinionated_personality(unsigned long *ret);
98 
99 const char *sigchld_code_to_string(int i) _const_;
100 int sigchld_code_from_string(const char *s) _pure_;
101 
102 int sched_policy_to_string_alloc(int i, char **s);
103 int sched_policy_from_string(const char *s);
104 
PTR_TO_PID(const void * p)105 static inline pid_t PTR_TO_PID(const void *p) {
106         return (pid_t) ((uintptr_t) p);
107 }
108 
PID_TO_PTR(pid_t pid)109 static inline void* PID_TO_PTR(pid_t pid) {
110         return (void*) ((uintptr_t) pid);
111 }
112 
113 void valgrind_summary_hack(void);
114 
115 int pid_compare_func(const pid_t *a, const pid_t *b);
116 
nice_is_valid(int n)117 static inline bool nice_is_valid(int n) {
118         return n >= PRIO_MIN && n < PRIO_MAX;
119 }
120 
sched_policy_is_valid(int i)121 static inline bool sched_policy_is_valid(int i) {
122         return IN_SET(i, SCHED_OTHER, SCHED_BATCH, SCHED_IDLE, SCHED_FIFO, SCHED_RR);
123 }
124 
sched_priority_is_valid(int i)125 static inline bool sched_priority_is_valid(int i) {
126         return i >= 0 && i <= sched_get_priority_max(SCHED_RR);
127 }
128 
pid_is_valid(pid_t p)129 static inline bool pid_is_valid(pid_t p) {
130         return p > 0;
131 }
132 
133 pid_t getpid_cached(void);
134 void reset_cached_pid(void);
135 
136 int must_be_root(void);
137 
138 typedef enum ForkFlags {
139         FORK_RESET_SIGNALS      = 1 <<  0, /* Reset all signal handlers and signal mask */
140         FORK_CLOSE_ALL_FDS      = 1 <<  1, /* Close all open file descriptors in the child, except for 0,1,2 */
141         FORK_DEATHSIG           = 1 <<  2, /* Set PR_DEATHSIG in the child to SIGTERM */
142         FORK_DEATHSIG_SIGINT    = 1 <<  3, /* Set PR_DEATHSIG in the child to SIGINT */
143         FORK_NULL_STDIO         = 1 <<  4, /* Connect 0,1,2 to /dev/null */
144         FORK_REOPEN_LOG         = 1 <<  5, /* Reopen log connection */
145         FORK_LOG                = 1 <<  6, /* Log above LOG_DEBUG log level about failures */
146         FORK_WAIT               = 1 <<  7, /* Wait until child exited */
147         FORK_NEW_MOUNTNS        = 1 <<  8, /* Run child in its own mount namespace */
148         FORK_MOUNTNS_SLAVE      = 1 <<  9, /* Make child's mount namespace MS_SLAVE */
149         FORK_RLIMIT_NOFILE_SAFE = 1 << 10, /* Set RLIMIT_NOFILE soft limit to 1K for select() compat */
150         FORK_STDOUT_TO_STDERR   = 1 << 11, /* Make stdout a copy of stderr */
151         FORK_FLUSH_STDIO        = 1 << 12, /* fflush() stdout (and stderr) before forking */
152         FORK_NEW_USERNS         = 1 << 13, /* Run child in its own user namespace */
153 } ForkFlags;
154 
155 int safe_fork_full(const char *name, const int except_fds[], size_t n_except_fds, ForkFlags flags, pid_t *ret_pid);
156 
safe_fork(const char * name,ForkFlags flags,pid_t * ret_pid)157 static inline int safe_fork(const char *name, ForkFlags flags, pid_t *ret_pid) {
158         return safe_fork_full(name, NULL, 0, flags, ret_pid);
159 }
160 
161 int namespace_fork(const char *outer_name, const char *inner_name, const int except_fds[], size_t n_except_fds, ForkFlags flags, int pidns_fd, int mntns_fd, int netns_fd, int userns_fd, int root_fd, pid_t *ret_pid);
162 
163 int set_oom_score_adjust(int value);
164 int get_oom_score_adjust(int *ret);
165 
166 /* The highest possibly (theoretic) pid_t value on this architecture. */
167 #define PID_T_MAX ((pid_t) INT32_MAX)
168 /* The maximum number of concurrent processes Linux allows on this architecture, as well as the highest valid PID value
169  * the kernel will potentially assign. This reflects a value compiled into the kernel (PID_MAX_LIMIT), and sets the
170  * upper boundary on what may be written to the /proc/sys/kernel/pid_max sysctl (but do note that the sysctl is off by
171  * 1, since PID 0 can never exist and there can hence only be one process less than the limit would suggest). Since
172  * these values are documented in proc(5) we feel quite confident that they are stable enough for the near future at
173  * least to define them here too. */
174 #define TASKS_MAX 4194303U
175 
176 assert_cc(TASKS_MAX <= (unsigned long) PID_T_MAX);
177 
178 /* Like TAKE_PTR() but for child PIDs, resetting them to 0 */
179 #define TAKE_PID(pid)                           \
180         ({                                      \
181                 pid_t *_ppid_ = &(pid);         \
182                 pid_t _pid_ = *_ppid_;          \
183                 *_ppid_ = 0;                    \
184                 _pid_;                          \
185         })
186 
187 int pidfd_get_pid(int fd, pid_t *ret);
188 
189 int setpriority_closest(int priority);
190 
191 bool invoked_as(char *argv[], const char *token);
192 
193 _noreturn_ void freeze(void);
194 
195 bool argv_looks_like_help(int argc, char **argv);
196