summaryrefslogtreecommitdiff
path: root/src/basic/cgroup-util.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/basic/cgroup-util.c')
-rw-r--r--src/basic/cgroup-util.c1917
1 files changed, 1917 insertions, 0 deletions
diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
new file mode 100644
index 0000000000..66857f118f
--- /dev/null
+++ b/src/basic/cgroup-util.c
@@ -0,0 +1,1917 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ 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 <errno.h>
+#include <unistd.h>
+#include <signal.h>
+#include <string.h>
+#include <stdlib.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <ftw.h>
+
+#include "cgroup-util.h"
+#include "set.h"
+#include "macro.h"
+#include "util.h"
+#include "formats-util.h"
+#include "process-util.h"
+#include "path-util.h"
+#include "unit-name.h"
+#include "fileio.h"
+#include "special.h"
+#include "mkdir.h"
+#include "login-util.h"
+
+int cg_enumerate_processes(const char *controller, const char *path, FILE **_f) {
+ _cleanup_free_ char *fs = NULL;
+ FILE *f;
+ int r;
+
+ assert(_f);
+
+ r = cg_get_path(controller, path, "cgroup.procs", &fs);
+ if (r < 0)
+ return r;
+
+ f = fopen(fs, "re");
+ if (!f)
+ return -errno;
+
+ *_f = f;
+ return 0;
+}
+
+int cg_read_pid(FILE *f, pid_t *_pid) {
+ unsigned long ul;
+
+ /* Note that the cgroup.procs might contain duplicates! See
+ * cgroups.txt for details. */
+
+ assert(f);
+ assert(_pid);
+
+ errno = 0;
+ if (fscanf(f, "%lu", &ul) != 1) {
+
+ if (feof(f))
+ return 0;
+
+ return errno ? -errno : -EIO;
+ }
+
+ if (ul <= 0)
+ return -EIO;
+
+ *_pid = (pid_t) ul;
+ return 1;
+}
+
+int cg_enumerate_subgroups(const char *controller, const char *path, DIR **_d) {
+ _cleanup_free_ char *fs = NULL;
+ int r;
+ DIR *d;
+
+ assert(_d);
+
+ /* This is not recursive! */
+
+ r = cg_get_path(controller, path, NULL, &fs);
+ if (r < 0)
+ return r;
+
+ d = opendir(fs);
+ if (!d)
+ return -errno;
+
+ *_d = d;
+ return 0;
+}
+
+int cg_read_subgroup(DIR *d, char **fn) {
+ struct dirent *de;
+
+ assert(d);
+ assert(fn);
+
+ FOREACH_DIRENT(de, d, return -errno) {
+ char *b;
+
+ if (de->d_type != DT_DIR)
+ continue;
+
+ if (streq(de->d_name, ".") ||
+ streq(de->d_name, ".."))
+ continue;
+
+ b = strdup(de->d_name);
+ if (!b)
+ return -ENOMEM;
+
+ *fn = b;
+ return 1;
+ }
+
+ return 0;
+}
+
+int cg_rmdir(const char *controller, const char *path) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ r = cg_get_path(controller, path, NULL, &p);
+ if (r < 0)
+ return r;
+
+ r = rmdir(p);
+ if (r < 0 && errno != ENOENT)
+ return -errno;
+
+ return 0;
+}
+
+int cg_kill(const char *controller, const char *path, int sig, bool sigcont, bool ignore_self, Set *s) {
+ _cleanup_set_free_ Set *allocated_set = NULL;
+ bool done = false;
+ int r, ret = 0;
+ pid_t my_pid;
+
+ assert(sig >= 0);
+
+ /* This goes through the tasks list and kills them all. This
+ * is repeated until no further processes are added to the
+ * tasks list, to properly handle forking processes */
+
+ if (!s) {
+ s = allocated_set = set_new(NULL);
+ if (!s)
+ return -ENOMEM;
+ }
+
+ my_pid = getpid();
+
+ do {
+ _cleanup_fclose_ FILE *f = NULL;
+ pid_t pid = 0;
+ done = true;
+
+ r = cg_enumerate_processes(controller, path, &f);
+ if (r < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ return r;
+
+ return ret;
+ }
+
+ while ((r = cg_read_pid(f, &pid)) > 0) {
+
+ if (ignore_self && pid == my_pid)
+ continue;
+
+ if (set_get(s, LONG_TO_PTR(pid)) == LONG_TO_PTR(pid))
+ continue;
+
+ /* If we haven't killed this process yet, kill
+ * it */
+ if (kill(pid, sig) < 0) {
+ if (ret >= 0 && errno != ESRCH)
+ ret = -errno;
+ } else {
+ if (sigcont && sig != SIGKILL)
+ kill(pid, SIGCONT);
+
+ if (ret == 0)
+ ret = 1;
+ }
+
+ done = false;
+
+ r = set_put(s, LONG_TO_PTR(pid));
+ if (r < 0) {
+ if (ret >= 0)
+ return r;
+
+ return ret;
+ }
+ }
+
+ if (r < 0) {
+ if (ret >= 0)
+ return r;
+
+ return ret;
+ }
+
+ /* To avoid racing against processes which fork
+ * quicker than we can kill them we repeat this until
+ * no new pids need to be killed. */
+
+ } while (!done);
+
+ return ret;
+}
+
+int cg_kill_recursive(const char *controller, const char *path, int sig, bool sigcont, bool ignore_self, bool rem, Set *s) {
+ _cleanup_set_free_ Set *allocated_set = NULL;
+ _cleanup_closedir_ DIR *d = NULL;
+ int r, ret = 0;
+ char *fn;
+
+ assert(path);
+ assert(sig >= 0);
+
+ if (!s) {
+ s = allocated_set = set_new(NULL);
+ if (!s)
+ return -ENOMEM;
+ }
+
+ ret = cg_kill(controller, path, sig, sigcont, ignore_self, s);
+
+ r = cg_enumerate_subgroups(controller, path, &d);
+ if (r < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ return r;
+
+ return ret;
+ }
+
+ while ((r = cg_read_subgroup(d, &fn)) > 0) {
+ _cleanup_free_ char *p = NULL;
+
+ p = strjoin(path, "/", fn, NULL);
+ free(fn);
+ if (!p)
+ return -ENOMEM;
+
+ r = cg_kill_recursive(controller, p, sig, sigcont, ignore_self, rem, s);
+ if (ret >= 0 && r != 0)
+ ret = r;
+ }
+
+ if (ret >= 0 && r < 0)
+ ret = r;
+
+ if (rem) {
+ r = cg_rmdir(controller, path);
+ if (r < 0 && ret >= 0 && r != -ENOENT && r != -EBUSY)
+ return r;
+ }
+
+ return ret;
+}
+
+int cg_migrate(const char *cfrom, const char *pfrom, const char *cto, const char *pto, bool ignore_self) {
+ bool done = false;
+ _cleanup_set_free_ Set *s = NULL;
+ int r, ret = 0;
+ pid_t my_pid;
+
+ assert(cfrom);
+ assert(pfrom);
+ assert(cto);
+ assert(pto);
+
+ s = set_new(NULL);
+ if (!s)
+ return -ENOMEM;
+
+ my_pid = getpid();
+
+ do {
+ _cleanup_fclose_ FILE *f = NULL;
+ pid_t pid = 0;
+ done = true;
+
+ r = cg_enumerate_processes(cfrom, pfrom, &f);
+ if (r < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ return r;
+
+ return ret;
+ }
+
+ while ((r = cg_read_pid(f, &pid)) > 0) {
+
+ /* This might do weird stuff if we aren't a
+ * single-threaded program. However, we
+ * luckily know we are not */
+ if (ignore_self && pid == my_pid)
+ continue;
+
+ if (set_get(s, LONG_TO_PTR(pid)) == LONG_TO_PTR(pid))
+ continue;
+
+ r = cg_attach(cto, pto, pid);
+ if (r < 0) {
+ if (ret >= 0 && r != -ESRCH)
+ ret = r;
+ } else if (ret == 0)
+ ret = 1;
+
+ done = false;
+
+ r = set_put(s, LONG_TO_PTR(pid));
+ if (r < 0) {
+ if (ret >= 0)
+ return r;
+
+ return ret;
+ }
+ }
+
+ if (r < 0) {
+ if (ret >= 0)
+ return r;
+
+ return ret;
+ }
+ } while (!done);
+
+ return ret;
+}
+
+int cg_migrate_recursive(
+ const char *cfrom,
+ const char *pfrom,
+ const char *cto,
+ const char *pto,
+ bool ignore_self,
+ bool rem) {
+
+ _cleanup_closedir_ DIR *d = NULL;
+ int r, ret = 0;
+ char *fn;
+
+ assert(cfrom);
+ assert(pfrom);
+ assert(cto);
+ assert(pto);
+
+ ret = cg_migrate(cfrom, pfrom, cto, pto, ignore_self);
+
+ r = cg_enumerate_subgroups(cfrom, pfrom, &d);
+ if (r < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ return r;
+
+ return ret;
+ }
+
+ while ((r = cg_read_subgroup(d, &fn)) > 0) {
+ _cleanup_free_ char *p = NULL;
+
+ p = strjoin(pfrom, "/", fn, NULL);
+ free(fn);
+ if (!p) {
+ if (ret >= 0)
+ return -ENOMEM;
+
+ return ret;
+ }
+
+ r = cg_migrate_recursive(cfrom, p, cto, pto, ignore_self, rem);
+ if (r != 0 && ret >= 0)
+ ret = r;
+ }
+
+ if (r < 0 && ret >= 0)
+ ret = r;
+
+ if (rem) {
+ r = cg_rmdir(cfrom, pfrom);
+ if (r < 0 && ret >= 0 && r != -ENOENT && r != -EBUSY)
+ return r;
+ }
+
+ return ret;
+}
+
+int cg_migrate_recursive_fallback(
+ const char *cfrom,
+ const char *pfrom,
+ const char *cto,
+ const char *pto,
+ bool ignore_self,
+ bool rem) {
+
+ int r;
+
+ assert(cfrom);
+ assert(pfrom);
+ assert(cto);
+ assert(pto);
+
+ r = cg_migrate_recursive(cfrom, pfrom, cto, pto, ignore_self, rem);
+ if (r < 0) {
+ char prefix[strlen(pto) + 1];
+
+ /* This didn't work? Then let's try all prefixes of the destination */
+
+ PATH_FOREACH_PREFIX(prefix, pto) {
+ r = cg_migrate_recursive(cfrom, pfrom, cto, prefix, ignore_self, rem);
+ if (r >= 0)
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static const char *normalize_controller(const char *controller) {
+
+ assert(controller);
+
+ if (startswith(controller, "name="))
+ return controller + 5;
+ else
+ return controller;
+}
+
+static int join_path(const char *controller, const char *path, const char *suffix, char **fs) {
+ char *t = NULL;
+
+ if (!isempty(controller)) {
+ if (!isempty(path) && !isempty(suffix))
+ t = strjoin("/sys/fs/cgroup/", controller, "/", path, "/", suffix, NULL);
+ else if (!isempty(path))
+ t = strjoin("/sys/fs/cgroup/", controller, "/", path, NULL);
+ else if (!isempty(suffix))
+ t = strjoin("/sys/fs/cgroup/", controller, "/", suffix, NULL);
+ else
+ t = strappend("/sys/fs/cgroup/", controller);
+ } else {
+ if (!isempty(path) && !isempty(suffix))
+ t = strjoin(path, "/", suffix, NULL);
+ else if (!isempty(path))
+ t = strdup(path);
+ else
+ return -EINVAL;
+ }
+
+ if (!t)
+ return -ENOMEM;
+
+ *fs = path_kill_slashes(t);
+ return 0;
+}
+
+int cg_get_path(const char *controller, const char *path, const char *suffix, char **fs) {
+ const char *p;
+ static thread_local bool good = false;
+
+ assert(fs);
+
+ if (controller && !cg_controller_is_valid(controller))
+ return -EINVAL;
+
+ if (_unlikely_(!good)) {
+ int r;
+
+ r = path_is_mount_point("/sys/fs/cgroup", 0);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ENOENT;
+
+ /* Cache this to save a few stat()s */
+ good = true;
+ }
+
+ p = controller ? normalize_controller(controller) : NULL;
+
+ return join_path(p, path, suffix, fs);
+}
+
+static int check_hierarchy(const char *p) {
+ const char *cc;
+
+ assert(p);
+
+ if (!filename_is_valid(p))
+ return 0;
+
+ /* Check if this controller actually really exists */
+ cc = strjoina("/sys/fs/cgroup/", p);
+ if (laccess(cc, F_OK) < 0)
+ return -errno;
+
+ return 0;
+}
+
+int cg_get_path_and_check(const char *controller, const char *path, const char *suffix, char **fs) {
+ const char *p;
+ int r;
+
+ assert(fs);
+
+ if (!cg_controller_is_valid(controller))
+ return -EINVAL;
+
+ /* Normalize the controller syntax */
+ p = normalize_controller(controller);
+
+ /* Check if this controller actually really exists */
+ r = check_hierarchy(p);
+ if (r < 0)
+ return r;
+
+ return join_path(p, path, suffix, fs);
+}
+
+static int trim_cb(const char *path, const struct stat *sb, int typeflag, struct FTW *ftwbuf) {
+ assert(path);
+ assert(sb);
+ assert(ftwbuf);
+
+ if (typeflag != FTW_DP)
+ return 0;
+
+ if (ftwbuf->level < 1)
+ return 0;
+
+ rmdir(path);
+ return 0;
+}
+
+int cg_trim(const char *controller, const char *path, bool delete_root) {
+ _cleanup_free_ char *fs = NULL;
+ int r = 0;
+
+ assert(path);
+
+ r = cg_get_path(controller, path, NULL, &fs);
+ if (r < 0)
+ return r;
+
+ errno = 0;
+ if (nftw(fs, trim_cb, 64, FTW_DEPTH|FTW_MOUNT|FTW_PHYS) != 0)
+ r = errno ? -errno : -EIO;
+
+ if (delete_root) {
+ if (rmdir(fs) < 0 && errno != ENOENT)
+ return -errno;
+ }
+
+ return r;
+}
+
+int cg_delete(const char *controller, const char *path) {
+ _cleanup_free_ char *parent = NULL;
+ int r;
+
+ assert(path);
+
+ r = path_get_parent(path, &parent);
+ if (r < 0)
+ return r;
+
+ r = cg_migrate_recursive(controller, path, controller, parent, false, true);
+ return r == -ENOENT ? 0 : r;
+}
+
+int cg_create(const char *controller, const char *path) {
+ _cleanup_free_ char *fs = NULL;
+ int r;
+
+ r = cg_get_path_and_check(controller, path, NULL, &fs);
+ if (r < 0)
+ return r;
+
+ r = mkdir_parents(fs, 0755);
+ if (r < 0)
+ return r;
+
+ if (mkdir(fs, 0755) < 0) {
+
+ if (errno == EEXIST)
+ return 0;
+
+ return -errno;
+ }
+
+ return 1;
+}
+
+int cg_create_and_attach(const char *controller, const char *path, pid_t pid) {
+ int r, q;
+
+ assert(pid >= 0);
+
+ r = cg_create(controller, path);
+ if (r < 0)
+ return r;
+
+ q = cg_attach(controller, path, pid);
+ if (q < 0)
+ return q;
+
+ /* This does not remove the cgroup on failure */
+ return r;
+}
+
+int cg_attach(const char *controller, const char *path, pid_t pid) {
+ _cleanup_free_ char *fs = NULL;
+ char c[DECIMAL_STR_MAX(pid_t) + 2];
+ int r;
+
+ assert(path);
+ assert(pid >= 0);
+
+ r = cg_get_path_and_check(controller, path, "cgroup.procs", &fs);
+ if (r < 0)
+ return r;
+
+ if (pid == 0)
+ pid = getpid();
+
+ snprintf(c, sizeof(c), PID_FMT"\n", pid);
+
+ return write_string_file_no_create(fs, c);
+}
+
+int cg_attach_fallback(const char *controller, const char *path, pid_t pid) {
+ int r;
+
+ assert(controller);
+ assert(path);
+ assert(pid >= 0);
+
+ r = cg_attach(controller, path, pid);
+ if (r < 0) {
+ char prefix[strlen(path) + 1];
+
+ /* This didn't work? Then let's try all prefixes of
+ * the destination */
+
+ PATH_FOREACH_PREFIX(prefix, path) {
+ r = cg_attach(controller, prefix, pid);
+ if (r >= 0)
+ break;
+ }
+ }
+
+ return 0;
+}
+
+int cg_set_group_access(
+ const char *controller,
+ const char *path,
+ mode_t mode,
+ uid_t uid,
+ gid_t gid) {
+
+ _cleanup_free_ char *fs = NULL;
+ int r;
+
+ assert(path);
+
+ if (mode != MODE_INVALID)
+ mode &= 0777;
+
+ r = cg_get_path(controller, path, NULL, &fs);
+ if (r < 0)
+ return r;
+
+ return chmod_and_chown(fs, mode, uid, gid);
+}
+
+int cg_set_task_access(
+ const char *controller,
+ const char *path,
+ mode_t mode,
+ uid_t uid,
+ gid_t gid) {
+
+ _cleanup_free_ char *fs = NULL, *procs = NULL;
+ int r;
+
+ assert(path);
+
+ if (mode == MODE_INVALID && uid == UID_INVALID && gid == GID_INVALID)
+ return 0;
+
+ if (mode != MODE_INVALID)
+ mode &= 0666;
+
+ r = cg_get_path(controller, path, "cgroup.procs", &fs);
+ if (r < 0)
+ return r;
+
+ r = chmod_and_chown(fs, mode, uid, gid);
+ if (r < 0)
+ return r;
+
+ /* Compatibility, Always keep values for "tasks" in sync with
+ * "cgroup.procs" */
+ r = cg_get_path(controller, path, "tasks", &procs);
+ if (r < 0)
+ return r;
+
+ return chmod_and_chown(procs, mode, uid, gid);
+}
+
+int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
+ _cleanup_fclose_ FILE *f = NULL;
+ char line[LINE_MAX];
+ const char *fs;
+ size_t cs;
+
+ assert(path);
+ assert(pid >= 0);
+
+ if (controller) {
+ if (!cg_controller_is_valid(controller))
+ return -EINVAL;
+
+ controller = normalize_controller(controller);
+ } else
+ controller = SYSTEMD_CGROUP_CONTROLLER;
+
+ fs = procfs_file_alloca(pid, "cgroup");
+
+ f = fopen(fs, "re");
+ if (!f)
+ return errno == ENOENT ? -ESRCH : -errno;
+
+ cs = strlen(controller);
+
+ FOREACH_LINE(line, f, return -errno) {
+ char *l, *p, *e;
+ size_t k;
+ const char *word, *state;
+ bool found = false;
+
+ truncate_nl(line);
+
+ l = strchr(line, ':');
+ if (!l)
+ continue;
+
+ l++;
+ e = strchr(l, ':');
+ if (!e)
+ continue;
+
+ *e = 0;
+
+ FOREACH_WORD_SEPARATOR(word, k, l, ",", state) {
+
+ if (k == cs && memcmp(word, controller, cs) == 0) {
+ found = true;
+ break;
+ }
+
+ if (k == 5 + cs &&
+ memcmp(word, "name=", 5) == 0 &&
+ memcmp(word+5, controller, cs) == 0) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found)
+ continue;
+
+ p = strdup(e + 1);
+ if (!p)
+ return -ENOMEM;
+
+ *path = p;
+ return 0;
+ }
+
+ return -ENOENT;
+}
+
+int cg_install_release_agent(const char *controller, const char *agent) {
+ _cleanup_free_ char *fs = NULL, *contents = NULL;
+ char *sc;
+ int r;
+
+ assert(agent);
+
+ r = cg_get_path(controller, NULL, "release_agent", &fs);
+ if (r < 0)
+ return r;
+
+ r = read_one_line_file(fs, &contents);
+ if (r < 0)
+ return r;
+
+ sc = strstrip(contents);
+ if (sc[0] == 0) {
+ r = write_string_file_no_create(fs, agent);
+ if (r < 0)
+ return r;
+ } else if (!streq(sc, agent))
+ return -EEXIST;
+
+ free(fs);
+ fs = NULL;
+ r = cg_get_path(controller, NULL, "notify_on_release", &fs);
+ if (r < 0)
+ return r;
+
+ free(contents);
+ contents = NULL;
+ r = read_one_line_file(fs, &contents);
+ if (r < 0)
+ return r;
+
+ sc = strstrip(contents);
+ if (streq(sc, "0")) {
+ r = write_string_file_no_create(fs, "1");
+ if (r < 0)
+ return r;
+
+ return 1;
+ }
+
+ if (!streq(sc, "1"))
+ return -EIO;
+
+ return 0;
+}
+
+int cg_uninstall_release_agent(const char *controller) {
+ _cleanup_free_ char *fs = NULL;
+ int r;
+
+ r = cg_get_path(controller, NULL, "notify_on_release", &fs);
+ if (r < 0)
+ return r;
+
+ r = write_string_file_no_create(fs, "0");
+ if (r < 0)
+ return r;
+
+ free(fs);
+ fs = NULL;
+
+ r = cg_get_path(controller, NULL, "release_agent", &fs);
+ if (r < 0)
+ return r;
+
+ r = write_string_file_no_create(fs, "");
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int cg_is_empty(const char *controller, const char *path, bool ignore_self) {
+ _cleanup_fclose_ FILE *f = NULL;
+ pid_t pid = 0, self_pid;
+ bool found = false;
+ int r;
+
+ assert(path);
+
+ r = cg_enumerate_processes(controller, path, &f);
+ if (r < 0)
+ return r == -ENOENT ? 1 : r;
+
+ self_pid = getpid();
+
+ while ((r = cg_read_pid(f, &pid)) > 0) {
+
+ if (ignore_self && pid == self_pid)
+ continue;
+
+ found = true;
+ break;
+ }
+
+ if (r < 0)
+ return r;
+
+ return !found;
+}
+
+int cg_is_empty_recursive(const char *controller, const char *path, bool ignore_self) {
+ _cleanup_closedir_ DIR *d = NULL;
+ char *fn;
+ int r;
+
+ assert(path);
+
+ r = cg_is_empty(controller, path, ignore_self);
+ if (r <= 0)
+ return r;
+
+ r = cg_enumerate_subgroups(controller, path, &d);
+ if (r < 0)
+ return r == -ENOENT ? 1 : r;
+
+ while ((r = cg_read_subgroup(d, &fn)) > 0) {
+ _cleanup_free_ char *p = NULL;
+
+ p = strjoin(path, "/", fn, NULL);
+ free(fn);
+ if (!p)
+ return -ENOMEM;
+
+ r = cg_is_empty_recursive(controller, p, ignore_self);
+ if (r <= 0)
+ return r;
+ }
+
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+int cg_split_spec(const char *spec, char **controller, char **path) {
+ const char *e;
+ char *t = NULL, *u = NULL;
+ _cleanup_free_ char *v = NULL;
+
+ assert(spec);
+
+ if (*spec == '/') {
+ if (!path_is_safe(spec))
+ return -EINVAL;
+
+ if (path) {
+ t = strdup(spec);
+ if (!t)
+ return -ENOMEM;
+
+ *path = path_kill_slashes(t);
+ }
+
+ if (controller)
+ *controller = NULL;
+
+ return 0;
+ }
+
+ e = strchr(spec, ':');
+ if (!e) {
+ if (!cg_controller_is_valid(spec))
+ return -EINVAL;
+
+ if (controller) {
+ t = strdup(normalize_controller(spec));
+ if (!t)
+ return -ENOMEM;
+
+ *controller = t;
+ }
+
+ if (path)
+ *path = NULL;
+
+ return 0;
+ }
+
+ v = strndup(spec, e-spec);
+ if (!v)
+ return -ENOMEM;
+ t = strdup(normalize_controller(v));
+ if (!t)
+ return -ENOMEM;
+ if (!cg_controller_is_valid(t)) {
+ free(t);
+ return -EINVAL;
+ }
+
+ if (streq(e+1, "")) {
+ u = strdup("/");
+ if (!u) {
+ free(t);
+ return -ENOMEM;
+ }
+ } else {
+ u = strdup(e+1);
+ if (!u) {
+ free(t);
+ return -ENOMEM;
+ }
+
+ if (!path_is_safe(u) ||
+ !path_is_absolute(u)) {
+ free(t);
+ free(u);
+ return -EINVAL;
+ }
+
+ path_kill_slashes(u);
+ }
+
+ if (controller)
+ *controller = t;
+ else
+ free(t);
+
+ if (path)
+ *path = u;
+ else
+ free(u);
+
+ return 0;
+}
+
+int cg_mangle_path(const char *path, char **result) {
+ _cleanup_free_ char *c = NULL, *p = NULL;
+ char *t;
+ int r;
+
+ assert(path);
+ assert(result);
+
+ /* First, check if it already is a filesystem path */
+ if (path_startswith(path, "/sys/fs/cgroup")) {
+
+ t = strdup(path);
+ if (!t)
+ return -ENOMEM;
+
+ *result = path_kill_slashes(t);
+ return 0;
+ }
+
+ /* Otherwise, treat it as cg spec */
+ r = cg_split_spec(path, &c, &p);
+ if (r < 0)
+ return r;
+
+ return cg_get_path(c ? c : SYSTEMD_CGROUP_CONTROLLER, p ? p : "/", NULL, result);
+}
+
+int cg_get_root_path(char **path) {
+ char *p, *e;
+ int r;
+
+ assert(path);
+
+ r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 1, &p);
+ if (r < 0)
+ return r;
+
+ e = endswith(p, "/" SPECIAL_SYSTEM_SLICE);
+ if (e)
+ *e = 0;
+
+ *path = p;
+ return 0;
+}
+
+int cg_shift_path(const char *cgroup, const char *root, const char **shifted) {
+ _cleanup_free_ char *rt = NULL;
+ char *p;
+ int r;
+
+ assert(cgroup);
+ assert(shifted);
+
+ if (!root) {
+ /* If the root was specified let's use that, otherwise
+ * let's determine it from PID 1 */
+
+ r = cg_get_root_path(&rt);
+ if (r < 0)
+ return r;
+
+ root = rt;
+ }
+
+ p = path_startswith(cgroup, root);
+ if (p)
+ *shifted = p - 1;
+ else
+ *shifted = cgroup;
+
+ return 0;
+}
+
+int cg_pid_get_path_shifted(pid_t pid, const char *root, char **cgroup) {
+ _cleanup_free_ char *raw = NULL;
+ const char *c;
+ int r;
+
+ assert(pid >= 0);
+ assert(cgroup);
+
+ r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &raw);
+ if (r < 0)
+ return r;
+
+ r = cg_shift_path(raw, root, &c);
+ if (r < 0)
+ return r;
+
+ if (c == raw) {
+ *cgroup = raw;
+ raw = NULL;
+ } else {
+ char *n;
+
+ n = strdup(c);
+ if (!n)
+ return -ENOMEM;
+
+ *cgroup = n;
+ }
+
+ return 0;
+}
+
+int cg_path_decode_unit(const char *cgroup, char **unit){
+ char *c, *s;
+ size_t n;
+
+ assert(cgroup);
+ assert(unit);
+
+ n = strcspn(cgroup, "/");
+ if (n < 3)
+ return -ENXIO;
+
+ c = strndupa(cgroup, n);
+ c = cg_unescape(c);
+
+ if (!unit_name_is_valid(c, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))
+ return -ENXIO;
+
+ s = strdup(c);
+ if (!s)
+ return -ENOMEM;
+
+ *unit = s;
+ return 0;
+}
+
+static bool valid_slice_name(const char *p, size_t n) {
+
+ if (!p)
+ return false;
+
+ if (n < strlen("x.slice"))
+ return false;
+
+ if (memcmp(p + n - 6, ".slice", 6) == 0) {
+ char buf[n+1], *c;
+
+ memcpy(buf, p, n);
+ buf[n] = 0;
+
+ c = cg_unescape(buf);
+
+ return unit_name_is_valid(c, UNIT_NAME_PLAIN);
+ }
+
+ return false;
+}
+
+static const char *skip_slices(const char *p) {
+ assert(p);
+
+ /* Skips over all slice assignments */
+
+ for (;;) {
+ size_t n;
+
+ p += strspn(p, "/");
+
+ n = strcspn(p, "/");
+ if (!valid_slice_name(p, n))
+ return p;
+
+ p += n;
+ }
+}
+
+int cg_path_get_unit(const char *path, char **ret) {
+ const char *e;
+ char *unit;
+ int r;
+
+ assert(path);
+ assert(ret);
+
+ e = skip_slices(path);
+
+ r = cg_path_decode_unit(e, &unit);
+ if (r < 0)
+ return r;
+
+ /* We skipped over the slices, don't accept any now */
+ if (endswith(unit, ".slice")) {
+ free(unit);
+ return -ENXIO;
+ }
+
+ *ret = unit;
+ return 0;
+}
+
+int cg_pid_get_unit(pid_t pid, char **unit) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(unit);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_unit(cgroup, unit);
+}
+
+/**
+ * Skip session-*.scope, but require it to be there.
+ */
+static const char *skip_session(const char *p) {
+ size_t n;
+
+ if (isempty(p))
+ return NULL;
+
+ p += strspn(p, "/");
+
+ n = strcspn(p, "/");
+ if (n < strlen("session-x.scope"))
+ return NULL;
+
+ if (memcmp(p, "session-", 8) == 0 && memcmp(p + n - 6, ".scope", 6) == 0) {
+ char buf[n - 8 - 6 + 1];
+
+ memcpy(buf, p + 8, n - 8 - 6);
+ buf[n - 8 - 6] = 0;
+
+ /* Note that session scopes never need unescaping,
+ * since they cannot conflict with the kernel's own
+ * names, hence we don't need to call cg_unescape()
+ * here. */
+
+ if (!session_id_valid(buf))
+ return false;
+
+ p += n;
+ p += strspn(p, "/");
+ return p;
+ }
+
+ return NULL;
+}
+
+/**
+ * Skip user@*.service, but require it to be there.
+ */
+static const char *skip_user_manager(const char *p) {
+ size_t n;
+
+ if (isempty(p))
+ return NULL;
+
+ p += strspn(p, "/");
+
+ n = strcspn(p, "/");
+ if (n < strlen("user@x.service"))
+ return NULL;
+
+ if (memcmp(p, "user@", 5) == 0 && memcmp(p + n - 8, ".service", 8) == 0) {
+ char buf[n - 5 - 8 + 1];
+
+ memcpy(buf, p + 5, n - 5 - 8);
+ buf[n - 5 - 8] = 0;
+
+ /* Note that user manager services never need unescaping,
+ * since they cannot conflict with the kernel's own
+ * names, hence we don't need to call cg_unescape()
+ * here. */
+
+ if (parse_uid(buf, NULL) < 0)
+ return NULL;
+
+ p += n;
+ p += strspn(p, "/");
+
+ return p;
+ }
+
+ return NULL;
+}
+
+static const char *skip_user_prefix(const char *path) {
+ const char *e, *t;
+
+ assert(path);
+
+ /* Skip slices, if there are any */
+ e = skip_slices(path);
+
+ /* Skip the user manager, if it's in the path now... */
+ t = skip_user_manager(e);
+ if (t)
+ return t;
+
+ /* Alternatively skip the user session if it is in the path... */
+ return skip_session(e);
+}
+
+int cg_path_get_user_unit(const char *path, char **ret) {
+ const char *t;
+
+ assert(path);
+ assert(ret);
+
+ t = skip_user_prefix(path);
+ if (!t)
+ return -ENXIO;
+
+ /* And from here on it looks pretty much the same as for a
+ * system unit, hence let's use the same parser from here
+ * on. */
+ return cg_path_get_unit(t, ret);
+}
+
+int cg_pid_get_user_unit(pid_t pid, char **unit) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(unit);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_user_unit(cgroup, unit);
+}
+
+int cg_path_get_machine_name(const char *path, char **machine) {
+ _cleanup_free_ char *u = NULL, *sl = NULL;
+ int r;
+
+ r = cg_path_get_unit(path, &u);
+ if (r < 0)
+ return r;
+
+ sl = strjoin("/run/systemd/machines/unit:", u, NULL);
+ if (!sl)
+ return -ENOMEM;
+
+ return readlink_malloc(sl, machine);
+}
+
+int cg_pid_get_machine_name(pid_t pid, char **machine) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(machine);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_machine_name(cgroup, machine);
+}
+
+int cg_path_get_session(const char *path, char **session) {
+ _cleanup_free_ char *unit = NULL;
+ char *start, *end;
+ int r;
+
+ assert(path);
+
+ r = cg_path_get_unit(path, &unit);
+ if (r < 0)
+ return r;
+
+ start = startswith(unit, "session-");
+ if (!start)
+ return -ENXIO;
+ end = endswith(start, ".scope");
+ if (!end)
+ return -ENXIO;
+
+ *end = 0;
+ if (!session_id_valid(start))
+ return -ENXIO;
+
+ if (session) {
+ char *rr;
+
+ rr = strdup(start);
+ if (!rr)
+ return -ENOMEM;
+
+ *session = rr;
+ }
+
+ return 0;
+}
+
+int cg_pid_get_session(pid_t pid, char **session) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_session(cgroup, session);
+}
+
+int cg_path_get_owner_uid(const char *path, uid_t *uid) {
+ _cleanup_free_ char *slice = NULL;
+ char *start, *end;
+ int r;
+
+ assert(path);
+
+ r = cg_path_get_slice(path, &slice);
+ if (r < 0)
+ return r;
+
+ start = startswith(slice, "user-");
+ if (!start)
+ return -ENXIO;
+ end = endswith(start, ".slice");
+ if (!end)
+ return -ENXIO;
+
+ *end = 0;
+ if (parse_uid(start, uid) < 0)
+ return -ENXIO;
+
+ return 0;
+}
+
+int cg_pid_get_owner_uid(pid_t pid, uid_t *uid) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_owner_uid(cgroup, uid);
+}
+
+int cg_path_get_slice(const char *p, char **slice) {
+ const char *e = NULL;
+
+ assert(p);
+ assert(slice);
+
+ /* Finds the right-most slice unit from the beginning, but
+ * stops before we come to the first non-slice unit. */
+
+ for (;;) {
+ size_t n;
+
+ p += strspn(p, "/");
+
+ n = strcspn(p, "/");
+ if (!valid_slice_name(p, n)) {
+
+ if (!e) {
+ char *s;
+
+ s = strdup("-.slice");
+ if (!s)
+ return -ENOMEM;
+
+ *slice = s;
+ return 0;
+ }
+
+ return cg_path_decode_unit(e, slice);
+ }
+
+ e = p;
+ p += n;
+ }
+}
+
+int cg_pid_get_slice(pid_t pid, char **slice) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(slice);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_slice(cgroup, slice);
+}
+
+int cg_path_get_user_slice(const char *p, char **slice) {
+ const char *t;
+ assert(p);
+ assert(slice);
+
+ t = skip_user_prefix(p);
+ if (!t)
+ return -ENXIO;
+
+ /* And now it looks pretty much the same as for a system
+ * slice, so let's just use the same parser from here on. */
+ return cg_path_get_slice(t, slice);
+}
+
+int cg_pid_get_user_slice(pid_t pid, char **slice) {
+ _cleanup_free_ char *cgroup = NULL;
+ int r;
+
+ assert(slice);
+
+ r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+ if (r < 0)
+ return r;
+
+ return cg_path_get_user_slice(cgroup, slice);
+}
+
+char *cg_escape(const char *p) {
+ bool need_prefix = false;
+
+ /* This implements very minimal escaping for names to be used
+ * as file names in the cgroup tree: any name which might
+ * conflict with a kernel name or is prefixed with '_' is
+ * prefixed with a '_'. That way, when reading cgroup names it
+ * is sufficient to remove a single prefixing underscore if
+ * there is one. */
+
+ /* The return value of this function (unlike cg_unescape())
+ * needs free()! */
+
+ if (p[0] == 0 ||
+ p[0] == '_' ||
+ p[0] == '.' ||
+ streq(p, "notify_on_release") ||
+ streq(p, "release_agent") ||
+ streq(p, "tasks"))
+ need_prefix = true;
+ else {
+ const char *dot;
+
+ dot = strrchr(p, '.');
+ if (dot) {
+
+ if (dot - p == 6 && memcmp(p, "cgroup", 6) == 0)
+ need_prefix = true;
+ else {
+ char *n;
+
+ n = strndupa(p, dot - p);
+
+ if (check_hierarchy(n) >= 0)
+ need_prefix = true;
+ }
+ }
+ }
+
+ if (need_prefix)
+ return strappend("_", p);
+ else
+ return strdup(p);
+}
+
+char *cg_unescape(const char *p) {
+ assert(p);
+
+ /* The return value of this function (unlike cg_escape())
+ * doesn't need free()! */
+
+ if (p[0] == '_')
+ return (char*) p+1;
+
+ return (char*) p;
+}
+
+#define CONTROLLER_VALID \
+ DIGITS LETTERS \
+ "_"
+
+bool cg_controller_is_valid(const char *p) {
+ const char *t, *s;
+
+ if (!p)
+ return false;
+
+ s = startswith(p, "name=");
+ if (s)
+ p = s;
+
+ if (*p == 0 || *p == '_')
+ return false;
+
+ for (t = p; *t; t++)
+ if (!strchr(CONTROLLER_VALID, *t))
+ return false;
+
+ if (t - p > FILENAME_MAX)
+ return false;
+
+ return true;
+}
+
+int cg_slice_to_path(const char *unit, char **ret) {
+ _cleanup_free_ char *p = NULL, *s = NULL, *e = NULL;
+ const char *dash;
+ int r;
+
+ assert(unit);
+ assert(ret);
+
+ if (streq(unit, "-.slice")) {
+ char *x;
+
+ x = strdup("");
+ if (!x)
+ return -ENOMEM;
+ *ret = x;
+ return 0;
+ }
+
+ if (!unit_name_is_valid(unit, UNIT_NAME_PLAIN))
+ return -EINVAL;
+
+ if (!endswith(unit, ".slice"))
+ return -EINVAL;
+
+ r = unit_name_to_prefix(unit, &p);
+ if (r < 0)
+ return r;
+
+ dash = strchr(p, '-');
+
+ /* Don't allow initial dashes */
+ if (dash == p)
+ return -EINVAL;
+
+ while (dash) {
+ _cleanup_free_ char *escaped = NULL;
+ char n[dash - p + sizeof(".slice")];
+
+ /* Don't allow trailing or double dashes */
+ if (dash[1] == 0 || dash[1] == '-')
+ return -EINVAL;
+
+ strcpy(stpncpy(n, p, dash - p), ".slice");
+ if (!unit_name_is_valid(n, UNIT_NAME_PLAIN))
+ return -EINVAL;
+
+ escaped = cg_escape(n);
+ if (!escaped)
+ return -ENOMEM;
+
+ if (!strextend(&s, escaped, "/", NULL))
+ return -ENOMEM;
+
+ dash = strchr(dash+1, '-');
+ }
+
+ e = cg_escape(unit);
+ if (!e)
+ return -ENOMEM;
+
+ if (!strextend(&s, e, NULL))
+ return -ENOMEM;
+
+ *ret = s;
+ s = NULL;
+
+ return 0;
+}
+
+int cg_set_attribute(const char *controller, const char *path, const char *attribute, const char *value) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ r = cg_get_path(controller, path, attribute, &p);
+ if (r < 0)
+ return r;
+
+ return write_string_file_no_create(p, value);
+}
+
+int cg_get_attribute(const char *controller, const char *path, const char *attribute, char **ret) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ r = cg_get_path(controller, path, attribute, &p);
+ if (r < 0)
+ return r;
+
+ return read_one_line_file(p, ret);
+}
+
+static const char mask_names[] =
+ "cpu\0"
+ "cpuacct\0"
+ "blkio\0"
+ "memory\0"
+ "devices\0";
+
+int cg_create_everywhere(CGroupControllerMask supported, CGroupControllerMask mask, const char *path) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ /* This one will create a cgroup in our private tree, but also
+ * duplicate it in the trees specified in mask, and remove it
+ * in all others */
+
+ /* First create the cgroup in our own hierarchy. */
+ r = cg_create(SYSTEMD_CGROUP_CONTROLLER, path);
+ if (r < 0)
+ return r;
+
+ /* Then, do the same in the other hierarchies */
+ NULSTR_FOREACH(n, mask_names) {
+ if (mask & bit)
+ cg_create(n, path);
+ else if (supported & bit)
+ cg_trim(n, path, true);
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+int cg_attach_everywhere(CGroupControllerMask supported, const char *path, pid_t pid, cg_migrate_callback_t path_callback, void *userdata) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, path, pid);
+ if (r < 0)
+ return r;
+
+ NULSTR_FOREACH(n, mask_names) {
+
+ if (supported & bit) {
+ const char *p = NULL;
+
+ if (path_callback)
+ p = path_callback(bit, userdata);
+
+ if (!p)
+ p = path;
+
+ cg_attach_fallback(n, path, pid);
+ }
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+int cg_attach_many_everywhere(CGroupControllerMask supported, const char *path, Set* pids, cg_migrate_callback_t path_callback, void *userdata) {
+ Iterator i;
+ void *pidp;
+ int r = 0;
+
+ SET_FOREACH(pidp, pids, i) {
+ pid_t pid = PTR_TO_LONG(pidp);
+ int q;
+
+ q = cg_attach_everywhere(supported, path, pid, path_callback, userdata);
+ if (q < 0)
+ r = q;
+ }
+
+ return r;
+}
+
+int cg_migrate_everywhere(CGroupControllerMask supported, const char *from, const char *to, cg_migrate_callback_t to_callback, void *userdata) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ if (!path_equal(from, to)) {
+ r = cg_migrate_recursive(SYSTEMD_CGROUP_CONTROLLER, from, SYSTEMD_CGROUP_CONTROLLER, to, false, true);
+ if (r < 0)
+ return r;
+ }
+
+ NULSTR_FOREACH(n, mask_names) {
+ if (supported & bit) {
+ const char *p = NULL;
+
+ if (to_callback)
+ p = to_callback(bit, userdata);
+
+ if (!p)
+ p = to;
+
+ cg_migrate_recursive_fallback(SYSTEMD_CGROUP_CONTROLLER, to, n, p, false, false);
+ }
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+int cg_trim_everywhere(CGroupControllerMask supported, const char *path, bool delete_root) {
+ CGroupControllerMask bit = 1;
+ const char *n;
+ int r;
+
+ r = cg_trim(SYSTEMD_CGROUP_CONTROLLER, path, delete_root);
+ if (r < 0)
+ return r;
+
+ NULSTR_FOREACH(n, mask_names) {
+ if (supported & bit)
+ cg_trim(n, path, delete_root);
+
+ bit <<= 1;
+ }
+
+ return 0;
+}
+
+CGroupControllerMask cg_mask_supported(void) {
+ CGroupControllerMask bit = 1, mask = 0;
+ const char *n;
+
+ NULSTR_FOREACH(n, mask_names) {
+ if (check_hierarchy(n) >= 0)
+ mask |= bit;
+
+ bit <<= 1;
+ }
+
+ return mask;
+}
+
+int cg_kernel_controllers(Set *controllers) {
+ _cleanup_fclose_ FILE *f = NULL;
+ char buf[LINE_MAX];
+ int r;
+
+ assert(controllers);
+
+ f = fopen("/proc/cgroups", "re");
+ if (!f) {
+ if (errno == ENOENT)
+ return 0;
+ return -errno;
+ }
+
+ /* Ignore the header line */
+ (void) fgets(buf, sizeof(buf), f);
+
+ for (;;) {
+ char *controller;
+ int enabled = 0;
+
+ errno = 0;
+ if (fscanf(f, "%ms %*i %*i %i", &controller, &enabled) != 2) {
+
+ if (feof(f))
+ break;
+
+ if (ferror(f) && errno)
+ return -errno;
+
+ return -EBADMSG;
+ }
+
+ if (!enabled) {
+ free(controller);
+ continue;
+ }
+
+ if (!filename_is_valid(controller)) {
+ free(controller);
+ return -EBADMSG;
+ }
+
+ r = set_consume(controllers, controller);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-09 00:37:38 +0000