diff options
Diffstat (limited to 'src/shared/cgroup-util.c')
-rw-r--r-- | src/shared/cgroup-util.c | 1917 |
1 files changed, 0 insertions, 1917 deletions
diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c deleted file mode 100644 index d83cdf7e5f..0000000000 --- a/src/shared/cgroup-util.c +++ /dev/null @@ -1,1917 +0,0 @@ -/*-*- 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-shared.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; -} |