576 lines
14 KiB
C
576 lines
14 KiB
C
/***
|
|
This file is part of systemd.
|
|
|
|
Copyright 2010 Lennart Poettering
|
|
|
|
systemd is free software; you can redistribute it and/or modify it
|
|
under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation; either version 2.1 of the License, or
|
|
(at your option) any later version.
|
|
|
|
systemd is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with systemd; If not, see <http://www.gnu.org/licenses/>.
|
|
***/
|
|
|
|
#include <assert.h>
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <signal.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <sys/types.h>
|
|
#include <sys/wait.h>
|
|
#include <unistd.h>
|
|
|
|
#include "escape.h"
|
|
#include "fd-util.h"
|
|
#include "fileio.h"
|
|
#include "log.h"
|
|
#include "process-util.h"
|
|
#include "signal-util.h"
|
|
#include "string-util.h"
|
|
#include "util.h"
|
|
|
|
int get_process_state(pid_t pid) {
|
|
const char *p;
|
|
char state;
|
|
int r;
|
|
_cleanup_free_ char *line = NULL;
|
|
|
|
assert(pid >= 0);
|
|
|
|
p = procfs_file_alloca(pid, "stat");
|
|
|
|
r = read_one_line_file(p, &line);
|
|
if (r == -ENOENT)
|
|
return -ESRCH;
|
|
if (r < 0)
|
|
return r;
|
|
|
|
p = strrchr(line, ')');
|
|
if (!p)
|
|
return -EIO;
|
|
|
|
p++;
|
|
|
|
if (sscanf(p, " %c", &state) != 1)
|
|
return -EIO;
|
|
|
|
return (unsigned char) state;
|
|
}
|
|
|
|
int get_process_comm(pid_t pid, char **name) {
|
|
const char *p;
|
|
int r;
|
|
|
|
assert(name);
|
|
assert(pid >= 0);
|
|
|
|
p = procfs_file_alloca(pid, "comm");
|
|
|
|
r = read_one_line_file(p, name);
|
|
if (r == -ENOENT)
|
|
return -ESRCH;
|
|
|
|
return r;
|
|
}
|
|
|
|
int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line) {
|
|
_cleanup_fclose_ FILE *f = NULL;
|
|
char *r = NULL, *k;
|
|
const char *p;
|
|
int c;
|
|
|
|
assert(line);
|
|
assert(pid >= 0);
|
|
|
|
p = procfs_file_alloca(pid, "cmdline");
|
|
|
|
f = fopen(p, "re");
|
|
if (!f) {
|
|
if (errno == ENOENT)
|
|
return -ESRCH;
|
|
return -errno;
|
|
}
|
|
|
|
if (max_length == 0) {
|
|
size_t len = 0, allocated = 0;
|
|
|
|
while ((c = getc(f)) != EOF) {
|
|
|
|
if (!GREEDY_REALLOC(r, allocated, len+2)) {
|
|
free(r);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
r[len++] = isprint(c) ? c : ' ';
|
|
}
|
|
|
|
if (len > 0)
|
|
r[len-1] = 0;
|
|
|
|
} else {
|
|
bool space = false;
|
|
size_t left;
|
|
|
|
r = new(char, max_length);
|
|
if (!r)
|
|
return -ENOMEM;
|
|
|
|
k = r;
|
|
left = max_length;
|
|
while ((c = getc(f)) != EOF) {
|
|
|
|
if (isprint(c)) {
|
|
if (space) {
|
|
if (left <= 4)
|
|
break;
|
|
|
|
*(k++) = ' ';
|
|
left--;
|
|
space = false;
|
|
}
|
|
|
|
if (left <= 4)
|
|
break;
|
|
|
|
*(k++) = (char) c;
|
|
left--;
|
|
} else
|
|
space = true;
|
|
}
|
|
|
|
if (left <= 4) {
|
|
size_t n = MIN(left-1, 3U);
|
|
memcpy(k, "...", n);
|
|
k[n] = 0;
|
|
} else
|
|
*k = 0;
|
|
}
|
|
|
|
/* Kernel threads have no argv[] */
|
|
if (isempty(r)) {
|
|
_cleanup_free_ char *t = NULL;
|
|
int h;
|
|
|
|
free(r);
|
|
|
|
if (!comm_fallback)
|
|
return -ENOENT;
|
|
|
|
h = get_process_comm(pid, &t);
|
|
if (h < 0)
|
|
return h;
|
|
|
|
r = strjoin("[", t, "]", NULL);
|
|
if (!r)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
*line = r;
|
|
return 0;
|
|
}
|
|
|
|
int is_kernel_thread(pid_t pid) {
|
|
const char *p;
|
|
size_t count;
|
|
char c;
|
|
bool eof;
|
|
FILE *f;
|
|
|
|
if (pid == 0 || pid == 1) /* pid 1, and we ourselves certainly aren't a kernel thread */
|
|
return 0;
|
|
|
|
assert(pid > 1);
|
|
|
|
p = procfs_file_alloca(pid, "cmdline");
|
|
f = fopen(p, "re");
|
|
if (!f) {
|
|
if (errno == ENOENT)
|
|
return -ESRCH;
|
|
return -errno;
|
|
}
|
|
|
|
count = fread(&c, 1, 1, f);
|
|
eof = feof(f);
|
|
fclose(f);
|
|
|
|
/* Kernel threads have an empty cmdline */
|
|
|
|
if (count <= 0)
|
|
return eof ? 1 : -errno;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int get_process_capeff(pid_t pid, char **capeff) {
|
|
const char *p;
|
|
int r;
|
|
|
|
assert(capeff);
|
|
assert(pid >= 0);
|
|
|
|
p = procfs_file_alloca(pid, "status");
|
|
|
|
r = get_proc_field(p, "CapEff", WHITESPACE, capeff);
|
|
if (r == -ENOENT)
|
|
return -ESRCH;
|
|
|
|
return r;
|
|
}
|
|
|
|
static int get_process_link_contents(const char *proc_file, char **name) {
|
|
int r;
|
|
|
|
assert(proc_file);
|
|
assert(name);
|
|
|
|
r = readlink_malloc(proc_file, name);
|
|
if (r == -ENOENT)
|
|
return -ESRCH;
|
|
if (r < 0)
|
|
return r;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int get_process_exe(pid_t pid, char **name) {
|
|
const char *p;
|
|
char *d;
|
|
int r;
|
|
|
|
assert(pid >= 0);
|
|
|
|
p = procfs_file_alloca(pid, "exe");
|
|
r = get_process_link_contents(p, name);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
d = endswith(*name, " (deleted)");
|
|
if (d)
|
|
*d = '\0';
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int get_process_id(pid_t pid, const char *field, uid_t *uid) {
|
|
_cleanup_fclose_ FILE *f = NULL;
|
|
char line[LINE_MAX];
|
|
const char *p;
|
|
|
|
assert(field);
|
|
assert(uid);
|
|
|
|
if (pid == 0)
|
|
return getuid();
|
|
|
|
p = procfs_file_alloca(pid, "status");
|
|
f = fopen(p, "re");
|
|
if (!f) {
|
|
if (errno == ENOENT)
|
|
return -ESRCH;
|
|
return -errno;
|
|
}
|
|
|
|
FOREACH_LINE(line, f, return -errno) {
|
|
char *l;
|
|
|
|
l = strstrip(line);
|
|
|
|
if (startswith(l, field)) {
|
|
l += strlen(field);
|
|
l += strspn(l, WHITESPACE);
|
|
|
|
l[strcspn(l, WHITESPACE)] = 0;
|
|
|
|
return parse_uid(l, uid);
|
|
}
|
|
}
|
|
|
|
return -EIO;
|
|
}
|
|
|
|
int get_process_uid(pid_t pid, uid_t *uid) {
|
|
return get_process_id(pid, "Uid:", uid);
|
|
}
|
|
|
|
int get_process_gid(pid_t pid, gid_t *gid) {
|
|
assert_cc(sizeof(uid_t) == sizeof(gid_t));
|
|
return get_process_id(pid, "Gid:", gid);
|
|
}
|
|
|
|
int get_process_cwd(pid_t pid, char **cwd) {
|
|
const char *p;
|
|
|
|
assert(pid >= 0);
|
|
|
|
p = procfs_file_alloca(pid, "cwd");
|
|
|
|
return get_process_link_contents(p, cwd);
|
|
}
|
|
|
|
int get_process_root(pid_t pid, char **root) {
|
|
const char *p;
|
|
|
|
assert(pid >= 0);
|
|
|
|
p = procfs_file_alloca(pid, "root");
|
|
|
|
return get_process_link_contents(p, root);
|
|
}
|
|
|
|
int get_process_environ(pid_t pid, char **env) {
|
|
_cleanup_fclose_ FILE *f = NULL;
|
|
_cleanup_free_ char *outcome = NULL;
|
|
int c;
|
|
const char *p;
|
|
size_t allocated = 0, sz = 0;
|
|
|
|
assert(pid >= 0);
|
|
assert(env);
|
|
|
|
p = procfs_file_alloca(pid, "environ");
|
|
|
|
f = fopen(p, "re");
|
|
if (!f) {
|
|
if (errno == ENOENT)
|
|
return -ESRCH;
|
|
return -errno;
|
|
}
|
|
|
|
while ((c = fgetc(f)) != EOF) {
|
|
if (!GREEDY_REALLOC(outcome, allocated, sz + 5))
|
|
return -ENOMEM;
|
|
|
|
if (c == '\0')
|
|
outcome[sz++] = '\n';
|
|
else
|
|
sz += cescape_char(c, outcome + sz);
|
|
}
|
|
|
|
if (!outcome) {
|
|
outcome = strdup("");
|
|
if (!outcome)
|
|
return -ENOMEM;
|
|
} else
|
|
outcome[sz] = '\0';
|
|
|
|
*env = outcome;
|
|
outcome = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
|
|
int r;
|
|
_cleanup_free_ char *line = NULL;
|
|
long unsigned ppid;
|
|
const char *p;
|
|
|
|
assert(pid >= 0);
|
|
assert(_ppid);
|
|
|
|
if (pid == 0) {
|
|
*_ppid = getppid();
|
|
return 0;
|
|
}
|
|
|
|
p = procfs_file_alloca(pid, "stat");
|
|
r = read_one_line_file(p, &line);
|
|
if (r == -ENOENT)
|
|
return -ESRCH;
|
|
if (r < 0)
|
|
return r;
|
|
|
|
/* Let's skip the pid and comm fields. The latter is enclosed
|
|
* in () but does not escape any () in its value, so let's
|
|
* skip over it manually */
|
|
|
|
p = strrchr(line, ')');
|
|
if (!p)
|
|
return -EIO;
|
|
|
|
p++;
|
|
|
|
if (sscanf(p, " "
|
|
"%*c " /* state */
|
|
"%lu ", /* ppid */
|
|
&ppid) != 1)
|
|
return -EIO;
|
|
|
|
if ((long unsigned) (pid_t) ppid != ppid)
|
|
return -ERANGE;
|
|
|
|
*_ppid = (pid_t) ppid;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int wait_for_terminate(pid_t pid, siginfo_t *status) {
|
|
siginfo_t dummy;
|
|
|
|
assert(pid >= 1);
|
|
|
|
if (!status)
|
|
status = &dummy;
|
|
|
|
for (;;) {
|
|
zero(*status);
|
|
|
|
if (waitid(P_PID, pid, status, WEXITED) < 0) {
|
|
|
|
if (errno == EINTR)
|
|
continue;
|
|
|
|
return -errno;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Return values:
|
|
* < 0 : wait_for_terminate() failed to get the state of the
|
|
* process, the process was terminated by a signal, or
|
|
* failed for an unknown reason.
|
|
* >=0 : The process terminated normally, and its exit code is
|
|
* returned.
|
|
*
|
|
* That is, success is indicated by a return value of zero, and an
|
|
* error is indicated by a non-zero value.
|
|
*
|
|
* A warning is emitted if the process terminates abnormally,
|
|
* and also if it returns non-zero unless check_exit_code is true.
|
|
*/
|
|
int wait_for_terminate_and_warn(const char *name, pid_t pid, bool check_exit_code) {
|
|
int r;
|
|
siginfo_t status;
|
|
|
|
assert(name);
|
|
assert(pid > 1);
|
|
|
|
r = wait_for_terminate(pid, &status);
|
|
if (r < 0)
|
|
return log_warning_errno(r, "Failed to wait for %s: %m", name);
|
|
|
|
if (status.si_code == CLD_EXITED) {
|
|
if (status.si_status != 0)
|
|
log_full(check_exit_code ? LOG_WARNING : LOG_DEBUG,
|
|
"%s failed with error code %i.", name, status.si_status);
|
|
else
|
|
log_debug("%s succeeded.", name);
|
|
|
|
return status.si_status;
|
|
} else if (status.si_code == CLD_KILLED ||
|
|
status.si_code == CLD_DUMPED) {
|
|
|
|
log_warning("%s terminated by signal %s.", name, signal_to_string(status.si_status));
|
|
return -EPROTO;
|
|
}
|
|
|
|
log_warning("%s failed due to unknown reason.", name);
|
|
return -EPROTO;
|
|
}
|
|
|
|
int kill_and_sigcont(pid_t pid, int sig) {
|
|
int r;
|
|
|
|
r = kill(pid, sig) < 0 ? -errno : 0;
|
|
|
|
if (r >= 0)
|
|
kill(pid, SIGCONT);
|
|
|
|
return r;
|
|
}
|
|
|
|
int getenv_for_pid(pid_t pid, const char *field, char **_value) {
|
|
_cleanup_fclose_ FILE *f = NULL;
|
|
char *value = NULL;
|
|
int r;
|
|
bool done = false;
|
|
size_t l;
|
|
const char *path;
|
|
|
|
assert(pid >= 0);
|
|
assert(field);
|
|
assert(_value);
|
|
|
|
path = procfs_file_alloca(pid, "environ");
|
|
|
|
f = fopen(path, "re");
|
|
if (!f) {
|
|
if (errno == ENOENT)
|
|
return -ESRCH;
|
|
return -errno;
|
|
}
|
|
|
|
l = strlen(field);
|
|
r = 0;
|
|
|
|
do {
|
|
char line[LINE_MAX];
|
|
unsigned i;
|
|
|
|
for (i = 0; i < sizeof(line)-1; i++) {
|
|
int c;
|
|
|
|
c = getc(f);
|
|
if (_unlikely_(c == EOF)) {
|
|
done = true;
|
|
break;
|
|
} else if (c == 0)
|
|
break;
|
|
|
|
line[i] = c;
|
|
}
|
|
line[i] = 0;
|
|
|
|
if (memcmp(line, field, l) == 0 && line[l] == '=') {
|
|
value = strdup(line + l + 1);
|
|
if (!value)
|
|
return -ENOMEM;
|
|
|
|
r = 1;
|
|
break;
|
|
}
|
|
|
|
} while (!done);
|
|
|
|
*_value = value;
|
|
return r;
|
|
}
|
|
|
|
bool pid_is_unwaited(pid_t pid) {
|
|
/* Checks whether a PID is still valid at all, including a zombie */
|
|
|
|
if (pid <= 0)
|
|
return false;
|
|
|
|
if (kill(pid, 0) >= 0)
|
|
return true;
|
|
|
|
return errno != ESRCH;
|
|
}
|
|
|
|
bool pid_is_alive(pid_t pid) {
|
|
int r;
|
|
|
|
/* Checks whether a PID is still valid and not a zombie */
|
|
|
|
if (pid <= 0)
|
|
return false;
|
|
|
|
r = get_process_state(pid);
|
|
if (r == -ESRCH || r == 'Z')
|
|
return false;
|
|
|
|
return true;
|
|
}
|