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-rw-r--r--src/shared/cgroup-util.c1111
-rw-r--r--src/shared/cgroup-util.h72
2 files changed, 1183 insertions, 0 deletions
diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
new file mode 100644
index 000000000..904d30095
--- /dev/null
+++ b/src/shared/cgroup-util.c
@@ -0,0 +1,1111 @@
+/*-*- 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU 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 "log.h"
+#include "set.h"
+#include "macro.h"
+#include "util.h"
+
+int cg_enumerate_processes(const char *controller, const char *path, FILE **_f) {
+ char *fs;
+ int r;
+ FILE *f;
+
+ assert(controller);
+ assert(path);
+ assert(_f);
+
+ if ((r = cg_get_path(controller, path, "cgroup.procs", &fs)) < 0)
+ return r;
+
+ f = fopen(fs, "re");
+ free(fs);
+
+ if (!f)
+ return -errno;
+
+ *_f = f;
+ return 0;
+}
+
+int cg_enumerate_tasks(const char *controller, const char *path, FILE **_f) {
+ char *fs;
+ int r;
+ FILE *f;
+
+ assert(controller);
+ assert(path);
+ assert(_f);
+
+ if ((r = cg_get_path(controller, path, "tasks", &fs)) < 0)
+ return r;
+
+ f = fopen(fs, "re");
+ free(fs);
+
+ 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. */
+
+ 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) {
+ char *fs;
+ int r;
+ DIR *d;
+
+ assert(controller);
+ assert(path);
+ assert(_d);
+
+ /* This is not recursive! */
+
+ if ((r = cg_get_path(controller, path, NULL, &fs)) < 0)
+ return r;
+
+ d = opendir(fs);
+ free(fs);
+
+ if (!d)
+ return -errno;
+
+ *_d = d;
+ return 0;
+}
+
+int cg_read_subgroup(DIR *d, char **fn) {
+ struct dirent *de;
+
+ assert(d);
+
+ errno = 0;
+ while ((de = readdir(d))) {
+ char *b;
+
+ if (de->d_type != DT_DIR)
+ continue;
+
+ if (streq(de->d_name, ".") ||
+ streq(de->d_name, ".."))
+ continue;
+
+ if (!(b = strdup(de->d_name)))
+ return -ENOMEM;
+
+ *fn = b;
+ return 1;
+ }
+
+ if (errno)
+ return -errno;
+
+ return 0;
+}
+
+int cg_rmdir(const char *controller, const char *path, bool honour_sticky) {
+ char *p;
+ int r;
+
+ r = cg_get_path(controller, path, NULL, &p);
+ if (r < 0)
+ return r;
+
+ if (honour_sticky) {
+ char *tasks;
+
+ /* If the sticky bit is set don't remove the directory */
+
+ tasks = strappend(p, "/tasks");
+ if (!tasks) {
+ free(p);
+ return -ENOMEM;
+ }
+
+ r = file_is_priv_sticky(tasks);
+ free(tasks);
+
+ if (r > 0) {
+ free(p);
+ return 0;
+ }
+ }
+
+ r = rmdir(p);
+ free(p);
+
+ return (r < 0 && errno != ENOENT) ? -errno : 0;
+}
+
+int cg_kill(const char *controller, const char *path, int sig, bool sigcont, bool ignore_self, Set *s) {
+ bool done = false;
+ int r, ret = 0;
+ pid_t my_pid;
+ FILE *f = NULL;
+ Set *allocated_set = NULL;
+
+ assert(controller);
+ assert(path);
+ 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)
+ if (!(s = allocated_set = set_new(trivial_hash_func, trivial_compare_func)))
+ return -ENOMEM;
+
+ my_pid = getpid();
+
+ do {
+ pid_t pid = 0;
+ done = true;
+
+ if ((r = cg_enumerate_processes(controller, path, &f)) < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ ret = r;
+
+ goto finish;
+ }
+
+ while ((r = cg_read_pid(f, &pid)) > 0) {
+
+ if (pid == my_pid && ignore_self)
+ 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 (ret == 0) {
+
+ if (sigcont)
+ kill(pid, SIGCONT);
+
+ ret = 1;
+ }
+
+ done = false;
+
+ if ((r = set_put(s, LONG_TO_PTR(pid))) < 0) {
+ if (ret >= 0)
+ ret = r;
+
+ goto finish;
+ }
+ }
+
+ if (r < 0) {
+ if (ret >= 0)
+ ret = r;
+
+ goto finish;
+ }
+
+ fclose(f);
+ f = NULL;
+
+ /* 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);
+
+finish:
+ if (allocated_set)
+ set_free(allocated_set);
+
+ if (f)
+ fclose(f);
+
+ return ret;
+}
+
+int cg_kill_recursive(const char *controller, const char *path, int sig, bool sigcont, bool ignore_self, bool rem, Set *s) {
+ int r, ret = 0;
+ DIR *d = NULL;
+ char *fn;
+ Set *allocated_set = NULL;
+
+ assert(path);
+ assert(controller);
+ assert(sig >= 0);
+
+ if (!s)
+ if (!(s = allocated_set = set_new(trivial_hash_func, trivial_compare_func)))
+ return -ENOMEM;
+
+ ret = cg_kill(controller, path, sig, sigcont, ignore_self, s);
+
+ if ((r = cg_enumerate_subgroups(controller, path, &d)) < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ ret = r;
+
+ goto finish;
+ }
+
+ while ((r = cg_read_subgroup(d, &fn)) > 0) {
+ char *p = NULL;
+
+ r = asprintf(&p, "%s/%s", path, fn);
+ free(fn);
+
+ if (r < 0) {
+ if (ret >= 0)
+ ret = -ENOMEM;
+
+ goto finish;
+ }
+
+ r = cg_kill_recursive(controller, p, sig, sigcont, ignore_self, rem, s);
+ free(p);
+
+ if (r != 0 && ret >= 0)
+ ret = r;
+ }
+
+ if (r < 0 && ret >= 0)
+ ret = r;
+
+ if (rem)
+ if ((r = cg_rmdir(controller, path, true)) < 0) {
+ if (ret >= 0 &&
+ r != -ENOENT &&
+ r != -EBUSY)
+ ret = r;
+ }
+
+finish:
+ if (d)
+ closedir(d);
+
+ if (allocated_set)
+ set_free(allocated_set);
+
+ return ret;
+}
+
+int cg_kill_recursive_and_wait(const char *controller, const char *path, bool rem) {
+ unsigned i;
+
+ assert(path);
+ assert(controller);
+
+ /* This safely kills all processes; first it sends a SIGTERM,
+ * then checks 8 times after 200ms whether the group is now
+ * empty, then kills everything that is left with SIGKILL and
+ * finally checks 5 times after 200ms each whether the group
+ * is finally empty. */
+
+ for (i = 0; i < 15; i++) {
+ int sig, r;
+
+ if (i <= 0)
+ sig = SIGTERM;
+ else if (i == 9)
+ sig = SIGKILL;
+ else
+ sig = 0;
+
+ if ((r = cg_kill_recursive(controller, path, sig, true, true, rem, NULL)) <= 0)
+ return r;
+
+ usleep(200 * USEC_PER_MSEC);
+ }
+
+ return 0;
+}
+
+int cg_migrate(const char *controller, const char *from, const char *to, bool ignore_self) {
+ bool done = false;
+ Set *s;
+ int r, ret = 0;
+ pid_t my_pid;
+ FILE *f = NULL;
+
+ assert(controller);
+ assert(from);
+ assert(to);
+
+ if (!(s = set_new(trivial_hash_func, trivial_compare_func)))
+ return -ENOMEM;
+
+ my_pid = getpid();
+
+ do {
+ pid_t pid = 0;
+ done = true;
+
+ if ((r = cg_enumerate_tasks(controller, from, &f)) < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ ret = r;
+
+ goto finish;
+ }
+
+ 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 (pid == my_pid && ignore_self)
+ continue;
+
+ if (set_get(s, LONG_TO_PTR(pid)) == LONG_TO_PTR(pid))
+ continue;
+
+ if ((r = cg_attach(controller, to, pid)) < 0) {
+ if (ret >= 0 && r != -ESRCH)
+ ret = r;
+ } else if (ret == 0)
+ ret = 1;
+
+ done = false;
+
+ if ((r = set_put(s, LONG_TO_PTR(pid))) < 0) {
+ if (ret >= 0)
+ ret = r;
+
+ goto finish;
+ }
+ }
+
+ if (r < 0) {
+ if (ret >= 0)
+ ret = r;
+
+ goto finish;
+ }
+
+ fclose(f);
+ f = NULL;
+
+ } while (!done);
+
+finish:
+ set_free(s);
+
+ if (f)
+ fclose(f);
+
+ return ret;
+}
+
+int cg_migrate_recursive(const char *controller, const char *from, const char *to, bool ignore_self, bool rem) {
+ int r, ret = 0;
+ DIR *d = NULL;
+ char *fn;
+
+ assert(controller);
+ assert(from);
+ assert(to);
+
+ ret = cg_migrate(controller, from, to, ignore_self);
+
+ if ((r = cg_enumerate_subgroups(controller, from, &d)) < 0) {
+ if (ret >= 0 && r != -ENOENT)
+ ret = r;
+ goto finish;
+ }
+
+ while ((r = cg_read_subgroup(d, &fn)) > 0) {
+ char *p = NULL;
+
+ r = asprintf(&p, "%s/%s", from, fn);
+ free(fn);
+
+ if (r < 0) {
+ if (ret >= 0)
+ ret = -ENOMEM;
+
+ goto finish;
+ }
+
+ r = cg_migrate_recursive(controller, p, to, ignore_self, rem);
+ free(p);
+
+ if (r != 0 && ret >= 0)
+ ret = r;
+ }
+
+ if (r < 0 && ret >= 0)
+ ret = r;
+
+ if (rem)
+ if ((r = cg_rmdir(controller, from, true)) < 0) {
+ if (ret >= 0 &&
+ r != -ENOENT &&
+ r != -EBUSY)
+ ret = r;
+ }
+
+finish:
+ if (d)
+ closedir(d);
+
+ return ret;
+}
+
+int cg_get_path(const char *controller, const char *path, const char *suffix, char **fs) {
+ const char *p;
+ char *t;
+ static __thread bool good = false;
+
+ assert(controller);
+ assert(fs);
+
+ if (_unlikely_(!good)) {
+ int r;
+
+ r = path_is_mount_point("/sys/fs/cgroup", false);
+ if (r <= 0)
+ return r < 0 ? r : -ENOENT;
+
+ /* Cache this to save a few stat()s */
+ good = true;
+ }
+
+ if (isempty(controller))
+ return -EINVAL;
+
+ /* This is a very minimal lookup from controller names to
+ * paths. Since we have mounted most hierarchies ourselves
+ * should be kinda safe, but eventually we might want to
+ * extend this to have a fallback to actually check
+ * /proc/mounts. Might need caching then. */
+
+ if (streq(controller, SYSTEMD_CGROUP_CONTROLLER))
+ p = "systemd";
+ else if (startswith(controller, "name="))
+ p = controller + 5;
+ else
+ p = controller;
+
+ if (path && suffix)
+ t = join("/sys/fs/cgroup/", p, "/", path, "/", suffix, NULL);
+ else if (path)
+ t = join("/sys/fs/cgroup/", p, "/", path, NULL);
+ else if (suffix)
+ t = join("/sys/fs/cgroup/", p, "/", suffix, NULL);
+ else
+ t = join("/sys/fs/cgroup/", p, NULL);
+
+ if (!t)
+ return -ENOMEM;
+
+ path_kill_slashes(t);
+
+ *fs = t;
+ return 0;
+}
+
+static int trim_cb(const char *path, const struct stat *sb, int typeflag, struct FTW *ftwbuf) {
+ char *p;
+ bool is_sticky;
+
+ if (typeflag != FTW_DP)
+ return 0;
+
+ if (ftwbuf->level < 1)
+ return 0;
+
+ p = strappend(path, "/tasks");
+ if (!p) {
+ errno = ENOMEM;
+ return 1;
+ }
+
+ is_sticky = file_is_priv_sticky(p) > 0;
+ free(p);
+
+ if (is_sticky)
+ return 0;
+
+ rmdir(path);
+ return 0;
+}
+
+int cg_trim(const char *controller, const char *path, bool delete_root) {
+ char *fs;
+ int r = 0;
+
+ assert(controller);
+ 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) {
+ bool is_sticky;
+ char *p;
+
+ p = strappend(fs, "/tasks");
+ if (!p) {
+ free(fs);
+ return -ENOMEM;
+ }
+
+ is_sticky = file_is_priv_sticky(p) > 0;
+ free(p);
+
+ if (!is_sticky)
+ if (rmdir(fs) < 0 && errno != ENOENT) {
+ if (r == 0)
+ r = -errno;
+ }
+ }
+
+ free(fs);
+
+ return r;
+}
+
+int cg_delete(const char *controller, const char *path) {
+ char *parent;
+ int r;
+
+ assert(controller);
+ assert(path);
+
+ if ((r = parent_of_path(path, &parent)) < 0)
+ return r;
+
+ r = cg_migrate_recursive(controller, path, parent, false, true);
+ free(parent);
+
+ return r == -ENOENT ? 0 : r;
+}
+
+int cg_create(const char *controller, const char *path) {
+ char *fs;
+ int r;
+
+ assert(controller);
+ assert(path);
+
+ if ((r = cg_get_path(controller, path, NULL, &fs)) < 0)
+ return r;
+
+ r = mkdir_parents(fs, 0755);
+
+ if (r >= 0) {
+ if (mkdir(fs, 0755) >= 0)
+ r = 1;
+ else if (errno == EEXIST)
+ r = 0;
+ else
+ r = -errno;
+ }
+
+ free(fs);
+
+ return r;
+}
+
+int cg_attach(const char *controller, const char *path, pid_t pid) {
+ char *fs;
+ int r;
+ char c[32];
+
+ assert(controller);
+ assert(path);
+ assert(pid >= 0);
+
+ if ((r = cg_get_path(controller, path, "tasks", &fs)) < 0)
+ return r;
+
+ if (pid == 0)
+ pid = getpid();
+
+ snprintf(c, sizeof(c), "%lu\n", (unsigned long) pid);
+ char_array_0(c);
+
+ r = write_one_line_file(fs, c);
+ free(fs);
+
+ return r;
+}
+
+int cg_create_and_attach(const char *controller, const char *path, pid_t pid) {
+ int r, q;
+
+ assert(controller);
+ assert(path);
+ assert(pid >= 0);
+
+ if ((r = cg_create(controller, path)) < 0)
+ return r;
+
+ if ((q = cg_attach(controller, path, pid)) < 0)
+ return q;
+
+ /* This does not remove the cgroup on failure */
+
+ return r;
+}
+
+int cg_set_group_access(const char *controller, const char *path, mode_t mode, uid_t uid, gid_t gid) {
+ char *fs;
+ int r;
+
+ assert(controller);
+ assert(path);
+
+ if (mode != (mode_t) -1)
+ mode &= 0777;
+
+ r = cg_get_path(controller, path, NULL, &fs);
+ if (r < 0)
+ return r;
+
+ r = chmod_and_chown(fs, mode, uid, gid);
+ free(fs);
+
+ return r;
+}
+
+int cg_set_task_access(const char *controller, const char *path, mode_t mode, uid_t uid, gid_t gid, int sticky) {
+ char *fs;
+ int r;
+
+ assert(controller);
+ assert(path);
+
+ if (mode == (mode_t) -1 && uid == (uid_t) -1 && gid == (gid_t) -1 && sticky < 0)
+ return 0;
+
+ if (mode != (mode_t) -1)
+ mode &= 0666;
+
+ r = cg_get_path(controller, path, "tasks", &fs);
+ if (r < 0)
+ return r;
+
+ if (sticky >= 0 && mode != (mode_t) -1)
+ /* Both mode and sticky param are passed */
+ mode |= (sticky ? S_ISVTX : 0);
+ else if ((sticky >= 0 && mode == (mode_t) -1) ||
+ (mode != (mode_t) -1 && sticky < 0)) {
+ struct stat st;
+
+ /* Only one param is passed, hence read the current
+ * mode from the file itself */
+
+ r = lstat(fs, &st);
+ if (r < 0) {
+ free(fs);
+ return -errno;
+ }
+
+ if (mode == (mode_t) -1)
+ /* No mode set, we just shall set the sticky bit */
+ mode = (st.st_mode & ~S_ISVTX) | (sticky ? S_ISVTX : 0);
+ else
+ /* Only mode set, leave sticky bit untouched */
+ mode = (st.st_mode & ~0777) | mode;
+ }
+
+ r = chmod_and_chown(fs, mode, uid, gid);
+ free(fs);
+
+ return r;
+}
+
+int cg_get_by_pid(const char *controller, pid_t pid, char **path) {
+ int r;
+ char *p = NULL;
+ FILE *f;
+ char *fs;
+ size_t cs;
+
+ assert(controller);
+ assert(path);
+ assert(pid >= 0);
+
+ if (pid == 0)
+ pid = getpid();
+
+ if (asprintf(&fs, "/proc/%lu/cgroup", (unsigned long) pid) < 0)
+ return -ENOMEM;
+
+ f = fopen(fs, "re");
+ free(fs);
+
+ if (!f)
+ return errno == ENOENT ? -ESRCH : -errno;
+
+ cs = strlen(controller);
+
+ while (!feof(f)) {
+ char line[LINE_MAX];
+ char *l;
+
+ errno = 0;
+ if (!(fgets(line, sizeof(line), f))) {
+ if (feof(f))
+ break;
+
+ r = errno ? -errno : -EIO;
+ goto finish;
+ }
+
+ truncate_nl(line);
+
+ if (!(l = strchr(line, ':')))
+ continue;
+
+ l++;
+ if (strncmp(l, controller, cs) != 0)
+ continue;
+
+ if (l[cs] != ':')
+ continue;
+
+ if (!(p = strdup(l + cs + 1))) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ *path = p;
+ r = 0;
+ goto finish;
+ }
+
+ r = -ENOENT;
+
+finish:
+ fclose(f);
+
+ return r;
+}
+
+int cg_install_release_agent(const char *controller, const char *agent) {
+ char *fs = NULL, *contents = NULL, *line = NULL, *sc;
+ int r;
+
+ assert(controller);
+ assert(agent);
+
+ if ((r = cg_get_path(controller, NULL, "release_agent", &fs)) < 0)
+ return r;
+
+ if ((r = read_one_line_file(fs, &contents)) < 0)
+ goto finish;
+
+ sc = strstrip(contents);
+ if (sc[0] == 0) {
+
+ if (asprintf(&line, "%s\n", agent) < 0) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ if ((r = write_one_line_file(fs, line)) < 0)
+ goto finish;
+
+ } else if (!streq(sc, agent)) {
+ r = -EEXIST;
+ goto finish;
+ }
+
+ free(fs);
+ fs = NULL;
+ if ((r = cg_get_path(controller, NULL, "notify_on_release", &fs)) < 0)
+ goto finish;
+
+ free(contents);
+ contents = NULL;
+ if ((r = read_one_line_file(fs, &contents)) < 0)
+ goto finish;
+
+ sc = strstrip(contents);
+
+ if (streq(sc, "0")) {
+ if ((r = write_one_line_file(fs, "1\n")) < 0)
+ goto finish;
+
+ r = 1;
+ } else if (!streq(sc, "1")) {
+ r = -EIO;
+ goto finish;
+ } else
+ r = 0;
+
+finish:
+ free(fs);
+ free(contents);
+ free(line);
+
+ return r;
+}
+
+int cg_is_empty(const char *controller, const char *path, bool ignore_self) {
+ pid_t pid = 0;
+ int r;
+ FILE *f = NULL;
+ bool found = false;
+
+ assert(controller);
+ assert(path);
+
+ if ((r = cg_enumerate_tasks(controller, path, &f)) < 0)
+ return r == -ENOENT ? 1 : r;
+
+ while ((r = cg_read_pid(f, &pid)) > 0) {
+
+ if (ignore_self && pid == getpid())
+ continue;
+
+ found = true;
+ break;
+ }
+
+ fclose(f);
+
+ if (r < 0)
+ return r;
+
+ return !found;
+}
+
+int cg_is_empty_recursive(const char *controller, const char *path, bool ignore_self) {
+ int r;
+ DIR *d = NULL;
+ char *fn;
+
+ assert(controller);
+ assert(path);
+
+ if ((r = cg_is_empty(controller, path, ignore_self)) <= 0)
+ return r;
+
+ if ((r = cg_enumerate_subgroups(controller, path, &d)) < 0)
+ return r == -ENOENT ? 1 : r;
+
+ while ((r = cg_read_subgroup(d, &fn)) > 0) {
+ char *p = NULL;
+
+ r = asprintf(&p, "%s/%s", path, fn);
+ free(fn);
+
+ if (r < 0) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ r = cg_is_empty_recursive(controller, p, ignore_self);
+ free(p);
+
+ if (r <= 0)
+ goto finish;
+ }
+
+ if (r >= 0)
+ r = 1;
+
+finish:
+
+ if (d)
+ closedir(d);
+
+ return r;
+}
+
+int cg_split_spec(const char *spec, char **controller, char **path) {
+ const char *e;
+ char *t = NULL, *u = NULL;
+
+ assert(spec);
+ assert(controller || path);
+
+ if (*spec == '/') {
+
+ if (path) {
+ if (!(t = strdup(spec)))
+ return -ENOMEM;
+
+ *path = t;
+ }
+
+ if (controller)
+ *controller = NULL;
+
+ return 0;
+ }
+
+ if (!(e = strchr(spec, ':'))) {
+
+ if (strchr(spec, '/') || spec[0] == 0)
+ return -EINVAL;
+
+ if (controller) {
+ if (!(t = strdup(spec)))
+ return -ENOMEM;
+
+ *controller = t;
+ }
+
+ if (path)
+ *path = NULL;
+
+ return 0;
+ }
+
+ if (e[1] != '/' ||
+ e == spec ||
+ memchr(spec, '/', e-spec))
+ return -EINVAL;
+
+ if (controller)
+ if (!(t = strndup(spec, e-spec)))
+ return -ENOMEM;
+
+ if (path)
+ if (!(u = strdup(e+1))) {
+ free(t);
+ return -ENOMEM;
+ }
+
+ if (controller)
+ *controller = t;
+
+ if (path)
+ *path = u;
+
+ return 0;
+}
+
+int cg_join_spec(const char *controller, const char *path, char **spec) {
+ assert(controller);
+ assert(path);
+
+ if (!path_is_absolute(path) ||
+ controller[0] == 0 ||
+ strchr(controller, ':') ||
+ strchr(controller, '/'))
+ return -EINVAL;
+
+ if (asprintf(spec, "%s:%s", controller, path) < 0)
+ return -ENOMEM;
+
+ return 0;
+}
+
+int cg_fix_path(const char *path, char **result) {
+ char *t, *c, *p;
+ int r;
+
+ assert(path);
+ assert(result);
+
+ /* First check if it already is a filesystem path */
+ if (path_is_absolute(path) &&
+ path_startswith(path, "/sys/fs/cgroup") &&
+ access(path, F_OK) >= 0) {
+
+ if (!(t = strdup(path)))
+ return -ENOMEM;
+
+ *result = t;
+ return 0;
+ }
+
+ /* Otherwise treat it as cg spec */
+ if ((r = cg_split_spec(path, &c, &p)) < 0)
+ return r;
+
+ r = cg_get_path(c ? c : SYSTEMD_CGROUP_CONTROLLER, p ? p : "/", NULL, result);
+ free(c);
+ free(p);
+
+ return r;
+}
+
+int cg_get_user_path(char **path) {
+ char *root, *p;
+
+ assert(path);
+
+ /* Figure out the place to put user cgroups below. We use the
+ * same as PID 1 has but with the "/system" suffix replaced by
+ * "/user" */
+
+ if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 1, &root) < 0)
+ p = strdup("/user");
+ else {
+ if (endswith(root, "/system"))
+ root[strlen(root) - 7] = 0;
+ else if (streq(root, "/"))
+ root[0] = 0;
+
+ p = strappend(root, "/user");
+ free(root);
+ }
+
+ if (!p)
+ return -ENOMEM;
+
+ *path = p;
+ return 0;
+}
diff --git a/src/shared/cgroup-util.h b/src/shared/cgroup-util.h
new file mode 100644
index 000000000..37e4255a9
--- /dev/null
+++ b/src/shared/cgroup-util.h
@@ -0,0 +1,72 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#ifndef foocgrouputilhfoo
+#define foocgrouputilhfoo
+
+/***
+ 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <dirent.h>
+
+#include "set.h"
+#include "def.h"
+
+int cg_enumerate_processes(const char *controller, const char *path, FILE **_f);
+int cg_enumerate_tasks(const char *controller, const char *path, FILE **_f);
+int cg_read_pid(FILE *f, pid_t *_pid);
+
+int cg_enumerate_subgroups(const char *controller, const char *path, DIR **_d);
+int cg_read_subgroup(DIR *d, char **fn);
+
+int cg_kill(const char *controller, const char *path, int sig, bool sigcont, bool ignore_self, Set *s);
+int cg_kill_recursive(const char *controller, const char *path, int sig, bool sigcont, bool ignore_self, bool remove, Set *s);
+int cg_kill_recursive_and_wait(const char *controller, const char *path, bool remove);
+
+int cg_migrate(const char *controller, const char *from, const char *to, bool ignore_self);
+int cg_migrate_recursive(const char *controller, const char *from, const char *to, bool ignore_self, bool remove);
+
+int cg_split_spec(const char *spec, char **controller, char **path);
+int cg_join_spec(const char *controller, const char *path, char **spec);
+int cg_fix_path(const char *path, char **result);
+
+int cg_get_path(const char *controller, const char *path, const char *suffix, char **fs);
+int cg_get_by_pid(const char *controller, pid_t pid, char **path);
+
+int cg_trim(const char *controller, const char *path, bool delete_root);
+
+int cg_rmdir(const char *controller, const char *path, bool honour_sticky);
+int cg_delete(const char *controller, const char *path);
+
+int cg_create(const char *controller, const char *path);
+int cg_attach(const char *controller, const char *path, pid_t pid);
+int cg_create_and_attach(const char *controller, const char *path, pid_t pid);
+
+int cg_set_group_access(const char *controller, const char *path, mode_t mode, uid_t uid, gid_t gid);
+int cg_set_task_access(const char *controller, const char *path, mode_t mode, uid_t uid, gid_t gid, int sticky);
+
+int cg_install_release_agent(const char *controller, const char *agent);
+
+int cg_is_empty(const char *controller, const char *path, bool ignore_self);
+int cg_is_empty_recursive(const char *controller, const char *path, bool ignore_self);
+
+int cg_get_user_path(char **path);
+
+#endif