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-rw-r--r--src/basic/process-util.c410
1 files changed, 364 insertions, 46 deletions
diff --git a/src/basic/process-util.c b/src/basic/process-util.c
index 2c05f2fee4..54b644ad56 100644
--- a/src/basic/process-util.c
+++ b/src/basic/process-util.c
@@ -17,22 +17,44 @@
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <linux/oom.h>
+#include <sched.h>
+#include <signal.h>
#include <stdbool.h>
-#include <sys/types.h>
-#include <string.h>
#include <stdio.h>
-#include <assert.h>
-#include <errno.h>
-#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/personality.h>
+#include <sys/prctl.h>
+#include <sys/types.h>
#include <sys/wait.h>
-#include <signal.h>
-#include <ctype.h>
-
+#include <syslog.h>
+#include <unistd.h>
+#ifdef HAVE_VALGRIND_VALGRIND_H
+#include <valgrind/valgrind.h>
+#endif
+
+#include "alloc-util.h"
+#include "architecture.h"
+#include "escape.h"
+#include "fd-util.h"
#include "fileio.h"
-#include "util.h"
+#include "fs-util.h"
+#include "ioprio.h"
#include "log.h"
-#include "signal-util.h"
+#include "macro.h"
+#include "missing.h"
#include "process-util.h"
+#include "raw-clone.h"
+#include "signal-util.h"
+#include "stat-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "user-util.h"
+#include "util.h"
int get_process_state(pid_t pid) {
const char *p;
@@ -43,7 +65,10 @@ int get_process_state(pid_t pid) {
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;
@@ -77,6 +102,7 @@ int get_process_comm(pid_t pid, char **name) {
int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line) {
_cleanup_fclose_ FILE *f = NULL;
+ bool space = false;
char *r = NULL, *k;
const char *p;
int c;
@@ -84,30 +110,62 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
assert(line);
assert(pid >= 0);
+ /* Retrieves a process' command line. Replaces unprintable characters while doing so by whitespace (coalescing
+ * multiple sequential ones into one). If max_length is != 0 will return a string of the specified size at most
+ * (the trailing NUL byte does count towards the length here!), abbreviated with a "..." ellipsis. If
+ * comm_fallback is true and the process has no command line set (the case for kernel threads), or has a
+ * command line that resolves to the empty string will return the "comm" name of the process instead.
+ *
+ * Returns -ESRCH if the process doesn't exist, and -ENOENT if the process has no command line (and
+ * comm_fallback is false). */
+
p = procfs_file_alloca(pid, "cmdline");
f = fopen(p, "re");
- if (!f)
+ if (!f) {
+ if (errno == ENOENT)
+ return -ESRCH;
return -errno;
+ }
+
+ if (max_length == 1) {
+
+ /* If there's only room for one byte, return the empty string */
+ r = new0(char, 1);
+ if (!r)
+ return -ENOMEM;
+
+ *line = r;
+ return 0;
- if (max_length == 0) {
+ } else if (max_length == 0) {
size_t len = 0, allocated = 0;
while ((c = getc(f)) != EOF) {
- if (!GREEDY_REALLOC(r, allocated, len+2)) {
+ if (!GREEDY_REALLOC(r, allocated, len+3)) {
free(r);
return -ENOMEM;
}
- r[len++] = isprint(c) ? c : ' ';
- }
+ if (isprint(c)) {
+ if (space) {
+ r[len++] = ' ';
+ space = false;
+ }
+
+ r[len++] = c;
+ } else if (len > 0)
+ space = true;
+ }
if (len > 0)
- r[len-1] = 0;
+ r[len] = 0;
+ else
+ r = mfree(r);
} else {
- bool space = false;
+ bool dotdotdot = false;
size_t left;
r = new(char, max_length);
@@ -119,28 +177,46 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
while ((c = getc(f)) != EOF) {
if (isprint(c)) {
+
if (space) {
- if (left <= 4)
+ if (left <= 2) {
+ dotdotdot = true;
break;
+ }
*(k++) = ' ';
left--;
space = false;
}
- if (left <= 4)
+ if (left <= 1) {
+ dotdotdot = true;
break;
+ }
*(k++) = (char) c;
left--;
- } else
+ } else if (k > r)
space = true;
}
- if (left <= 4) {
- size_t n = MIN(left-1, 3U);
- memcpy(k, "...", n);
- k[n] = 0;
+ if (dotdotdot) {
+ if (max_length <= 4) {
+ k = r;
+ left = max_length;
+ } else {
+ k = r + max_length - 4;
+ left = 4;
+
+ /* Eat up final spaces */
+ while (k > r && isspace(k[-1])) {
+ k--;
+ left++;
+ }
+ }
+
+ strncpy(k, "...", left-1);
+ k[left-1] = 0;
} else
*k = 0;
}
@@ -159,7 +235,37 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
if (h < 0)
return h;
- r = strjoin("[", t, "]", NULL);
+ if (max_length == 0)
+ r = strjoin("[", t, "]", NULL);
+ else {
+ size_t l;
+
+ l = strlen(t);
+
+ if (l + 3 <= max_length)
+ r = strjoin("[", t, "]", NULL);
+ else if (max_length <= 6) {
+
+ r = new(char, max_length);
+ if (!r)
+ return -ENOMEM;
+
+ memcpy(r, "[...]", max_length-1);
+ r[max_length-1] = 0;
+ } else {
+ char *e;
+
+ t[max_length - 6] = 0;
+
+ /* Chop off final spaces */
+ e = strchr(t, 0);
+ while (e > t && isspace(e[-1]))
+ e--;
+ *e = 0;
+
+ r = strjoin("[", t, "...]", NULL);
+ }
+ }
if (!r)
return -ENOMEM;
}
@@ -168,6 +274,37 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
return 0;
}
+void rename_process(const char name[8]) {
+ assert(name);
+
+ /* This is a like a poor man's setproctitle(). It changes the
+ * comm field, argv[0], and also the glibc's internally used
+ * name of the process. For the first one a limit of 16 chars
+ * applies, to the second one usually one of 10 (i.e. length
+ * of "/sbin/init"), to the third one one of 7 (i.e. length of
+ * "systemd"). If you pass a longer string it will be
+ * truncated */
+
+ (void) prctl(PR_SET_NAME, name);
+
+ if (program_invocation_name)
+ strncpy(program_invocation_name, name, strlen(program_invocation_name));
+
+ if (saved_argc > 0) {
+ int i;
+
+ if (saved_argv[0])
+ strncpy(saved_argv[0], name, strlen(saved_argv[0]));
+
+ for (i = 1; i < saved_argc; i++) {
+ if (!saved_argv[i])
+ break;
+
+ memzero(saved_argv[i], strlen(saved_argv[i]));
+ }
+ }
+}
+
int is_kernel_thread(pid_t pid) {
const char *p;
size_t count;
@@ -175,15 +312,18 @@ int is_kernel_thread(pid_t pid) {
bool eof;
FILE *f;
- if (pid == 0)
+ if (pid == 0 || pid == 1) /* pid 1, and we ourselves certainly aren't a kernel thread */
return 0;
- assert(pid > 0);
+ assert(pid > 1);
p = procfs_file_alloca(pid, "cmdline");
f = fopen(p, "re");
- if (!f)
+ if (!f) {
+ if (errno == ENOENT)
+ return -ESRCH;
return -errno;
+ }
count = fread(&c, 1, 1, f);
eof = feof(f);
@@ -199,13 +339,18 @@ int is_kernel_thread(pid_t pid) {
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");
- return get_status_field(p, "\nCapEff:", capeff);
+ 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) {
@@ -215,8 +360,10 @@ static int get_process_link_contents(const char *proc_file, char **name) {
assert(name);
r = readlink_malloc(proc_file, name);
+ if (r == -ENOENT)
+ return -ESRCH;
if (r < 0)
- return r == -ENOENT ? -ESRCH : r;
+ return r;
return 0;
}
@@ -248,13 +395,13 @@ static int get_process_id(pid_t pid, const char *field, uid_t *uid) {
assert(field);
assert(uid);
- if (pid == 0)
- return getuid();
-
p = procfs_file_alloca(pid, "status");
f = fopen(p, "re");
- if (!f)
+ if (!f) {
+ if (errno == ENOENT)
+ return -ESRCH;
return -errno;
+ }
FOREACH_LINE(line, f, return -errno) {
char *l;
@@ -316,8 +463,11 @@ int get_process_environ(pid_t pid, char **env) {
p = procfs_file_alloca(pid, "environ");
f = fopen(p, "re");
- if (!f)
+ if (!f) {
+ if (errno == ENOENT)
+ return -ESRCH;
return -errno;
+ }
while ((c = fgetc(f)) != EOF) {
if (!GREEDY_REALLOC(outcome, allocated, sz + 5))
@@ -329,17 +479,20 @@ int get_process_environ(pid_t pid, char **env) {
sz += cescape_char(c, outcome + sz);
}
- if (sz == 0)
- return -ENOENT;
+ if (!outcome) {
+ outcome = strdup("");
+ if (!outcome)
+ return -ENOMEM;
+ } else
+ outcome[sz] = '\0';
- outcome[sz] = '\0';
*env = outcome;
outcome = NULL;
return 0;
}
-int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
+int get_process_ppid(pid_t pid, pid_t *_ppid) {
int r;
_cleanup_free_ char *line = NULL;
long unsigned ppid;
@@ -355,6 +508,8 @@ int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
p = procfs_file_alloca(pid, "stat");
r = read_one_line_file(p, &line);
+ if (r == -ENOENT)
+ return -ESRCH;
if (r < 0)
return r;
@@ -398,7 +553,7 @@ int wait_for_terminate(pid_t pid, siginfo_t *status) {
if (errno == EINTR)
continue;
- return -errno;
+ return negative_errno();
}
return 0;
@@ -449,13 +604,31 @@ int wait_for_terminate_and_warn(const char *name, pid_t pid, bool check_exit_cod
return -EPROTO;
}
+void sigkill_wait(pid_t pid) {
+ assert(pid > 1);
+
+ if (kill(pid, SIGKILL) > 0)
+ (void) wait_for_terminate(pid, NULL);
+}
+
+void sigkill_waitp(pid_t *pid) {
+ if (!pid)
+ return;
+ if (*pid <= 1)
+ return;
+
+ sigkill_wait(*pid);
+}
+
int kill_and_sigcont(pid_t pid, int sig) {
int r;
r = kill(pid, sig) < 0 ? -errno : 0;
- if (r >= 0)
- kill(pid, SIGCONT);
+ /* If this worked, also send SIGCONT, unless we already just sent a SIGCONT, or SIGKILL was sent which isn't
+ * affected by a process being suspended anyway. */
+ if (r >= 0 && !IN_SET(SIGCONT, SIGKILL))
+ (void) kill(pid, SIGCONT);
return r;
}
@@ -475,8 +648,11 @@ int getenv_for_pid(pid_t pid, const char *field, char **_value) {
path = procfs_file_alloca(pid, "environ");
f = fopen(path, "re");
- if (!f)
+ if (!f) {
+ if (errno == ENOENT)
+ return -ESRCH;
return -errno;
+ }
l = strlen(field);
r = 0;
@@ -517,9 +693,12 @@ int getenv_for_pid(pid_t pid, const char *field, char **_value) {
bool pid_is_unwaited(pid_t pid) {
/* Checks whether a PID is still valid at all, including a zombie */
- if (pid <= 0)
+ if (pid < 0)
return false;
+ if (pid <= 1) /* If we or PID 1 would be dead and have been waited for, this code would not be running */
+ return true;
+
if (kill(pid, 0) >= 0)
return true;
@@ -531,12 +710,151 @@ bool pid_is_alive(pid_t pid) {
/* Checks whether a PID is still valid and not a zombie */
- if (pid <= 0)
+ if (pid < 0)
return false;
+ if (pid <= 1) /* If we or PID 1 would be a zombie, this code would not be running */
+ return true;
+
r = get_process_state(pid);
- if (r == -ENOENT || r == 'Z')
+ if (r == -ESRCH || r == 'Z')
return false;
return true;
}
+
+int pid_from_same_root_fs(pid_t pid) {
+ const char *root;
+
+ if (pid < 0)
+ return 0;
+
+ root = procfs_file_alloca(pid, "root");
+
+ return files_same(root, "/proc/1/root");
+}
+
+bool is_main_thread(void) {
+ static thread_local int cached = 0;
+
+ if (_unlikely_(cached == 0))
+ cached = getpid() == gettid() ? 1 : -1;
+
+ return cached > 0;
+}
+
+noreturn void freeze(void) {
+
+ log_close();
+
+ /* Make sure nobody waits for us on a socket anymore */
+ close_all_fds(NULL, 0);
+
+ sync();
+
+ for (;;)
+ pause();
+}
+
+bool oom_score_adjust_is_valid(int oa) {
+ return oa >= OOM_SCORE_ADJ_MIN && oa <= OOM_SCORE_ADJ_MAX;
+}
+
+unsigned long personality_from_string(const char *p) {
+ int architecture;
+
+ if (!p)
+ return PERSONALITY_INVALID;
+
+ /* Parse a personality specifier. We use our own identifiers that indicate specific ABIs, rather than just
+ * hints regarding the register size, since we want to keep things open for multiple locally supported ABIs for
+ * the same register size. */
+
+ architecture = architecture_from_string(p);
+ if (architecture < 0)
+ return PERSONALITY_INVALID;
+
+ if (architecture == native_architecture())
+ return PER_LINUX;
+#ifdef SECONDARY_ARCHITECTURE
+ if (architecture == SECONDARY_ARCHITECTURE)
+ return PER_LINUX32;
+#endif
+
+ return PERSONALITY_INVALID;
+}
+
+const char* personality_to_string(unsigned long p) {
+ int architecture = _ARCHITECTURE_INVALID;
+
+ if (p == PER_LINUX)
+ architecture = native_architecture();
+#ifdef SECONDARY_ARCHITECTURE
+ else if (p == PER_LINUX32)
+ architecture = SECONDARY_ARCHITECTURE;
+#endif
+
+ if (architecture < 0)
+ return NULL;
+
+ return architecture_to_string(architecture);
+}
+
+void valgrind_summary_hack(void) {
+#ifdef HAVE_VALGRIND_VALGRIND_H
+ if (getpid() == 1 && RUNNING_ON_VALGRIND) {
+ pid_t pid;
+ pid = raw_clone(SIGCHLD);
+ if (pid < 0)
+ log_emergency_errno(errno, "Failed to fork off valgrind helper: %m");
+ else if (pid == 0)
+ exit(EXIT_SUCCESS);
+ else {
+ log_info("Spawned valgrind helper as PID "PID_FMT".", pid);
+ (void) wait_for_terminate(pid, NULL);
+ }
+ }
+#endif
+}
+
+int pid_compare_func(const void *a, const void *b) {
+ const pid_t *p = a, *q = b;
+
+ /* Suitable for usage in qsort() */
+
+ if (*p < *q)
+ return -1;
+ if (*p > *q)
+ return 1;
+ return 0;
+}
+
+static const char *const ioprio_class_table[] = {
+ [IOPRIO_CLASS_NONE] = "none",
+ [IOPRIO_CLASS_RT] = "realtime",
+ [IOPRIO_CLASS_BE] = "best-effort",
+ [IOPRIO_CLASS_IDLE] = "idle"
+};
+
+DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(ioprio_class, int, INT_MAX);
+
+static const char *const sigchld_code_table[] = {
+ [CLD_EXITED] = "exited",
+ [CLD_KILLED] = "killed",
+ [CLD_DUMPED] = "dumped",
+ [CLD_TRAPPED] = "trapped",
+ [CLD_STOPPED] = "stopped",
+ [CLD_CONTINUED] = "continued",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(sigchld_code, int);
+
+static const char* const sched_policy_table[] = {
+ [SCHED_OTHER] = "other",
+ [SCHED_BATCH] = "batch",
+ [SCHED_IDLE] = "idle",
+ [SCHED_FIFO] = "fifo",
+ [SCHED_RR] = "rr"
+};
+
+DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(sched_policy, int, INT_MAX);
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-08-14 23:46:08 +0000