X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fcgroup-util.c;h=c17e1d4d1bde18080cd82a7ebb2b1bd6778a384f;hp=b2fb324a18c995255e954ff2bc5e644c5d8f0ba9;hb=3df82d5a8cdc510f518fd5e234ccb3233b748719;hpb=3474ae3c7e1981301d0b35bc89d759ca13f06e8f

diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
index b2fb324a1..c17e1d4d1 100644
--- a/src/shared/cgroup-util.c
+++ b/src/shared/cgroup-util.c
@@ -34,17 +34,21 @@
 #include "set.h"
 #include "macro.h"
 #include "util.h"
+#include "path-util.h"
+#include "strv.h"
+#include "unit-name.h"
+#include "fileio.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)
+        r = cg_get_path(controller, path, "cgroup.procs", &fs);
+        if (r < 0)
                 return r;
 
         f = fopen(fs, "re");
@@ -62,11 +66,11 @@ int cg_enumerate_tasks(const char *controller, const char *path, FILE **_f) {
         int r;
         FILE *f;
 
-        assert(controller);
         assert(path);
         assert(_f);
 
-        if ((r = cg_get_path(controller, path, "tasks", &fs)) < 0)
+        r = cg_get_path(controller, path, "tasks", &fs);
+        if (r < 0)
                 return r;
 
         f = fopen(fs, "re");
@@ -106,13 +110,13 @@ int cg_enumerate_subgroups(const char *controller, const char *path, DIR **_d) {
         int r;
         DIR *d;
 
-        assert(controller);
         assert(path);
         assert(_d);
 
         /* This is not recursive! */
 
-        if ((r = cg_get_path(controller, path, NULL, &fs)) < 0)
+        r = cg_get_path(controller, path, NULL, &fs);
+        if (r < 0)
                 return r;
 
         d = opendir(fs);
@@ -372,18 +376,20 @@ int cg_kill_recursive_and_wait(const char *controller, const char *path, bool re
         return 0;
 }
 
-int cg_migrate(const char *controller, const char *from, const char *to, bool ignore_self) {
+int cg_migrate(const char *cfrom, const char *pfrom, const char *cto, const char *pto, bool ignore_self) {
         bool done = false;
-        Set *s;
+        _cleanup_set_free_ Set *s = NULL;
         int r, ret = 0;
         pid_t my_pid;
-        FILE *f = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
 
-        assert(controller);
-        assert(from);
-        assert(to);
+        assert(cfrom);
+        assert(pfrom);
+        assert(cto);
+        assert(pto);
 
-        if (!(s = set_new(trivial_hash_func, trivial_compare_func)))
+        s = set_new(trivial_hash_func, trivial_compare_func);
+        if (!s)
                 return -ENOMEM;
 
         my_pid = getpid();
@@ -392,11 +398,12 @@ int cg_migrate(const char *controller, const char *from, const char *to, bool ig
                 pid_t pid = 0;
                 done = true;
 
-                if ((r = cg_enumerate_tasks(controller, from, &f)) < 0) {
+                r = cg_enumerate_tasks(cfrom, pfrom, &f);
+                if (r < 0) {
                         if (ret >= 0 && r != -ENOENT)
                                 ret = r;
 
-                        goto finish;
+                        return ret;
                 }
 
                 while ((r = cg_read_pid(f, &pid)) > 0) {
@@ -410,7 +417,8 @@ int cg_migrate(const char *controller, const char *from, const char *to, bool ig
                         if (set_get(s, LONG_TO_PTR(pid)) == LONG_TO_PTR(pid))
                                 continue;
 
-                        if ((r = cg_attach(controller, to, pid)) < 0) {
+                        r = cg_attach(cto, pto, pid);
+                        if (r < 0) {
                                 if (ret >= 0 && r != -ESRCH)
                                         ret = r;
                         } else if (ret == 0)
@@ -418,11 +426,12 @@ int cg_migrate(const char *controller, const char *from, const char *to, bool ig
 
                         done = false;
 
-                        if ((r = set_put(s, LONG_TO_PTR(pid))) < 0) {
+                        r = set_put(s, LONG_TO_PTR(pid));
+                        if (r < 0) {
                                 if (ret >= 0)
                                         ret = r;
 
-                                goto finish;
+                                return ret;
                         }
                 }
 
@@ -430,56 +439,48 @@ int cg_migrate(const char *controller, const char *from, const char *to, bool ig
                         if (ret >= 0)
                                 ret = r;
 
-                        goto finish;
+                        return ret;
                 }
 
                 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 cg_migrate_recursive(const char *cfrom, const char *pfrom, const char *cto, const char *pto, bool ignore_self, bool rem) {
         int r, ret = 0;
-        DIR *d = NULL;
+        _cleanup_closedir_ DIR *d = NULL;
         char *fn;
 
-        assert(controller);
-        assert(from);
-        assert(to);
+        assert(cfrom);
+        assert(pfrom);
+        assert(cto);
+        assert(pto);
 
-        ret = cg_migrate(controller, from, to, ignore_self);
+        ret = cg_migrate(cfrom, pfrom, cto, pto, ignore_self);
 
-        if ((r = cg_enumerate_subgroups(controller, from, &d)) < 0) {
+        r = cg_enumerate_subgroups(cfrom, pfrom, &d);
+        if (r < 0) {
                 if (ret >= 0 && r != -ENOENT)
                         ret = r;
-                goto finish;
+                return ret;
         }
 
         while ((r = cg_read_subgroup(d, &fn)) > 0) {
-                char *p = NULL;
+                _cleanup_free_ char *p = NULL;
 
-                r = asprintf(&p, "%s/%s", from, fn);
+                p = strjoin(pfrom, "/", fn, NULL);
                 free(fn);
-
-                if (r < 0) {
+                if (!p) {
                         if (ret >= 0)
                                 ret = -ENOMEM;
 
-                        goto finish;
+                        return ret;
                 }
 
-                r = cg_migrate_recursive(controller, p, to, ignore_self, rem);
-                free(p);
-
+                r = cg_migrate_recursive(cfrom, p, cto, pto, ignore_self, rem);
                 if (r != 0 && ret >= 0)
                         ret = r;
         }
@@ -487,17 +488,11 @@ int cg_migrate_recursive(const char *controller, const char *from, const char *t
         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);
+        if (rem) {
+                r = cg_rmdir(cfrom, pfrom, true);
+                if (r < 0 && ret >= 0 && r != -ENOENT && r != -EBUSY)
+                        return r;
+        }
 
         return ret;
 }
@@ -513,16 +508,26 @@ static const char *normalize_controller(const char *controller) {
 }
 
 static int join_path(const char *controller, const char *path, const char *suffix, char **fs) {
-        char *t;
-
-        if (path && suffix)
-                t = join("/sys/fs/cgroup/", controller, "/", path, "/", suffix, NULL);
-        else if (path)
-                t = join("/sys/fs/cgroup/", controller, "/", path, NULL);
-        else if (suffix)
-                t = join("/sys/fs/cgroup/", controller, "/", suffix, NULL);
-        else
-                t = join("/sys/fs/cgroup/", controller, NULL);
+        char *t = NULL;
+
+        if (!(controller || path))
+                return -EINVAL;
+
+        if (controller) {
+                if (path && suffix)
+                        t = strjoin("/sys/fs/cgroup/", controller, "/", path, "/", suffix, NULL);
+                else if (path)
+                        t = strjoin("/sys/fs/cgroup/", controller, "/", path, NULL);
+                else if (suffix)
+                        t = strjoin("/sys/fs/cgroup/", controller, "/", suffix, NULL);
+                else
+                        t = strjoin("/sys/fs/cgroup/", controller, NULL);
+        } else {
+                if (path && suffix)
+                        t = strjoin(path, "/", suffix, NULL);
+                else if (path)
+                        t = strdup(path);
+        }
 
         if (!t)
                 return -ENOMEM;
@@ -537,12 +542,8 @@ int cg_get_path(const char *controller, const char *path, const char *suffix, ch
         const char *p;
         static __thread bool good = false;
 
-        assert(controller);
         assert(fs);
 
-        if (isempty(controller))
-                return -EINVAL;
-
         if (_unlikely_(!good)) {
                 int r;
 
@@ -554,14 +555,27 @@ int cg_get_path(const char *controller, const char *path, const char *suffix, ch
                 good = true;
         }
 
-        p = normalize_controller(controller);
-
+        p = controller ? normalize_controller(controller) : NULL;
         return join_path(p, path, suffix, fs);
 }
 
+static int check(const char *p) {
+        char *cc;
+
+        assert(p);
+
+        /* Check if this controller actually really exists */
+        cc = alloca(sizeof("/sys/fs/cgroup/") + strlen(p));
+        strcpy(stpcpy(cc, "/sys/fs/cgroup/"), p);
+        if (access(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;
-        char *cc;
+        int r;
 
         assert(controller);
         assert(fs);
@@ -569,13 +583,13 @@ int cg_get_path_and_check(const char *controller, const char *path, const char *
         if (isempty(controller))
                 return -EINVAL;
 
+        /* Normalize the controller syntax */
         p = normalize_controller(controller);
 
         /* Check if this controller actually really exists */
-        cc = alloca(sizeof("/sys/fs/cgroup/") + strlen(p));
-        strcpy(stpcpy(cc, "/sys/fs/cgroup/"), p);
-        if (access(cc, F_OK) < 0)
-                return -errno;
+        r = check(p);
+        if (r < 0)
+                return r;
 
         return join_path(p, path, suffix, fs);
 }
@@ -653,19 +667,19 @@ int cg_delete(const char *controller, const char *path) {
         assert(controller);
         assert(path);
 
-        if ((r = parent_of_path(path, &parent)) < 0)
+        if ((r = path_get_parent(path, &parent)) < 0)
                 return r;
 
-        r = cg_migrate_recursive(controller, path, parent, false, true);
+        r = cg_migrate_recursive(controller, path, controller, parent, false, true);
         free(parent);
 
         return r == -ENOENT ? 0 : r;
 }
 
 int cg_attach(const char *controller, const char *path, pid_t pid) {
-        char *fs;
+        _cleanup_free_ char *fs = NULL;
+        char c[DECIMAL_STR_MAX(pid_t) + 2];
         int r;
-        char c[32];
 
         assert(controller);
         assert(path);
@@ -679,16 +693,18 @@ int cg_attach(const char *controller, const char *path, pid_t pid) {
                 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;
+        return write_string_file(fs, c);
 }
 
-int cg_set_group_access(const char *controller, const char *path, mode_t mode, uid_t uid, gid_t gid) {
-        char *fs;
+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(controller);
@@ -701,14 +717,18 @@ int cg_set_group_access(const char *controller, const char *path, mode_t mode, u
         if (r < 0)
                 return r;
 
-        r = chmod_and_chown(fs, mode, uid, gid);
-        free(fs);
-
-        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, int sticky) {
-        char *fs;
+int cg_set_task_access(
+                const char *controller,
+                const char *path,
+                mode_t mode,
+                uid_t uid,
+                gid_t gid,
+                int sticky) {
+
+        _cleanup_free_ char *fs = NULL, *procs = NULL;
         int r;
 
         assert(controller);
@@ -735,10 +755,8 @@ int cg_set_task_access(const char *controller, const char *path, mode_t mode, ui
                  * mode from the file itself */
 
                 r = lstat(fs, &st);
-                if (r < 0) {
-                        free(fs);
+                if (r < 0)
                         return -errno;
-                }
 
                 if (mode == (mode_t) -1)
                         /* No mode set, we just shall set the sticky bit */
@@ -749,9 +767,15 @@ int cg_set_task_access(const char *controller, const char *path, mode_t mode, ui
         }
 
         r = chmod_and_chown(fs, mode, uid, gid);
-        free(fs);
+        if (r < 0)
+                return r;
 
-        return r;
+        /* Always keep values for "cgroup.procs" in sync with "tasks" */
+        r = cg_get_path(controller, path, "cgroup.procs", &procs);
+        if (r < 0)
+                return r;
+
+        return chmod_and_chown(procs, mode, uid, gid);
 }
 
 int cg_get_by_pid(const char *controller, pid_t pid, char **path) {
@@ -798,7 +822,7 @@ int cg_get_by_pid(const char *controller, pid_t pid, char **path) {
                         continue;
 
                 l++;
-                if (strncmp(l, controller, cs) != 0)
+                if (!strneq(l, controller, cs))
                         continue;
 
                 if (l[cs] != ':')
@@ -843,7 +867,8 @@ int cg_install_release_agent(const char *controller, const char *agent) {
                         goto finish;
                 }
 
-                if ((r = write_one_line_file(fs, line)) < 0)
+                r = write_string_file(fs, line);
+                if (r < 0)
                         goto finish;
 
         } else if (!streq(sc, agent)) {
@@ -864,7 +889,7 @@ int cg_install_release_agent(const char *controller, const char *agent) {
         sc = strstrip(contents);
 
         if (streq(sc, "0")) {
-                if ((r = write_one_line_file(fs, "1\n")) < 0)
+                if ((r = write_string_file(fs, "1\n")) < 0)
                         goto finish;
 
                 r = 1;
@@ -883,20 +908,22 @@ finish:
 }
 
 int cg_is_empty(const char *controller, const char *path, bool ignore_self) {
-        pid_t pid = 0;
+        pid_t pid = 0, self_pid;
         int r;
         FILE *f = NULL;
         bool found = false;
 
-        assert(controller);
         assert(path);
 
-        if ((r = cg_enumerate_tasks(controller, path, &f)) < 0)
+        r = cg_enumerate_tasks(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 == getpid())
+                if (ignore_self && pid == self_pid)
                         continue;
 
                 found = true;
@@ -911,18 +938,32 @@ int cg_is_empty(const char *controller, const char *path, bool ignore_self) {
         return !found;
 }
 
+int cg_is_empty_by_spec(const char *spec, bool ignore_self) {
+        int r;
+        _cleanup_free_ char *controller = NULL, *path = NULL;
+
+        assert(spec);
+
+        r = cg_split_spec(spec, &controller, &path);
+        if (r < 0)
+                return r;
+
+        return cg_is_empty(controller, path, ignore_self);
+}
+
 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)
+        r = cg_is_empty(controller, path, ignore_self);
+        if (r <= 0)
                 return r;
 
-        if ((r = cg_enumerate_subgroups(controller, path, &d)) < 0)
+        r = cg_enumerate_subgroups(controller, path, &d);
+        if (r < 0)
                 return r == -ENOENT ? 1 : r;
 
         while ((r = cg_read_subgroup(d, &fn)) > 0) {
@@ -959,12 +1000,14 @@ int cg_split_spec(const char *spec, char **controller, char **path) {
         char *t = NULL, *u = NULL;
 
         assert(spec);
-        assert(controller || path);
 
         if (*spec == '/') {
+                if (!path_is_safe(spec))
+                        return -EINVAL;
 
                 if (path) {
-                        if (!(t = strdup(spec)))
+                        t = strdup(spec);
+                        if (!t)
                                 return -ENOMEM;
 
                         *path = t;
@@ -976,13 +1019,14 @@ int cg_split_spec(const char *spec, char **controller, char **path) {
                 return 0;
         }
 
-        if (!(e = strchr(spec, ':'))) {
-
-                if (strchr(spec, '/') || spec[0] == 0)
+        e = strchr(spec, ':');
+        if (!e) {
+                if (!filename_is_safe(spec))
                         return -EINVAL;
 
                 if (controller) {
-                        if (!(t = strdup(spec)))
+                        t = strdup(spec);
+                        if (!t)
                                 return -ENOMEM;
 
                         *controller = t;
@@ -994,26 +1038,34 @@ int cg_split_spec(const char *spec, char **controller, char **path) {
                 return 0;
         }
 
-        if (e[1] != '/' ||
-            e == spec ||
-            memchr(spec, '/', e-spec))
+        t = strndup(spec, e-spec);
+        if (!t)
+                return -ENOMEM;
+        if (!filename_is_safe(t)) {
+                free(t);
                 return -EINVAL;
+        }
 
-        if (controller)
-                if (!(t = strndup(spec, e-spec)))
-                        return -ENOMEM;
-
-        if (path)
-                if (!(u = strdup(e+1))) {
-                        free(t);
-                        return -ENOMEM;
-                }
+        u = strdup(e+1);
+        if (!u) {
+                free(t);
+                return -ENOMEM;
+        }
+        if (!path_is_safe(u)) {
+                free(t);
+                free(u);
+                return -EINVAL;
+        }
 
         if (controller)
                 *controller = t;
+        else
+                free(t);
 
         if (path)
                 *path = u;
+        else
+                free(u);
 
         return 0;
 }
@@ -1042,11 +1094,11 @@ int cg_fix_path(const char *path, char **result) {
         assert(result);
 
         /* First check if it already is a filesystem path */
-        if (path_is_absolute(path) &&
-            path_startswith(path, "/sys/fs/cgroup") &&
+        if (path_startswith(path, "/sys/fs/cgroup") &&
             access(path, F_OK) >= 0) {
 
-                if (!(t = strdup(path)))
+                t = strdup(path);
+                if (!t)
                         return -ENOMEM;
 
                 *result = t;
@@ -1054,7 +1106,8 @@ int cg_fix_path(const char *path, char **result) {
         }
 
         /* Otherwise treat it as cg spec */
-        if ((r = cg_split_spec(path, &c, &p)) < 0)
+        r = cg_split_spec(path, &c, &p);
+        if (r < 0)
                 return r;
 
         r = cg_get_path(c ? c : SYSTEMD_CGROUP_CONTROLLER, p ? p : "/", NULL, result);
@@ -1091,3 +1144,197 @@ int cg_get_user_path(char **path) {
         *path = p;
         return 0;
 }
+
+char **cg_shorten_controllers(char **controllers) {
+        char **f, **t;
+
+        controllers = strv_uniq(controllers);
+
+        if (!controllers)
+                return controllers;
+
+        for (f = controllers, t = controllers; *f; f++) {
+                int r;
+                const char *p;
+
+                if (streq(*f, "systemd") || streq(*f, SYSTEMD_CGROUP_CONTROLLER)) {
+                        free(*f);
+                        continue;
+                }
+
+                p = normalize_controller(*f);
+
+                r = check(p);
+                if (r < 0) {
+                        log_debug("Controller %s is not available, removing from controllers list.", *f);
+                        free(*f);
+                        continue;
+                }
+
+                *(t++) = *f;
+        }
+
+        *t = NULL;
+        return controllers;
+}
+
+int cg_pid_get_cgroup(pid_t pid, char **root, char **cgroup) {
+        char *cg_process, *cg_init, *p;
+        int r;
+
+        assert(pid >= 0);
+
+        if (pid == 0)
+                pid = getpid();
+
+        r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, pid, &cg_process);
+        if (r < 0)
+                return r;
+
+        r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 1, &cg_init);
+        if (r < 0) {
+                free(cg_process);
+                return r;
+        }
+
+        if (endswith(cg_init, "/system"))
+                cg_init[strlen(cg_init)-7] = 0;
+        else if (streq(cg_init, "/"))
+                cg_init[0] = 0;
+
+        if (startswith(cg_process, cg_init))
+                p = cg_process + strlen(cg_init);
+        else
+                p = cg_process;
+
+        free(cg_init);
+
+        if (cgroup) {
+                char* c;
+
+                c = strdup(p);
+                if (!c) {
+                        free(cg_process);
+                        return -ENOMEM;
+                }
+
+                *cgroup = c;
+        }
+
+        if (root) {
+                cg_process[p-cg_process] = 0;
+                *root = cg_process;
+        } else
+                free(cg_process);
+
+        return 0;
+}
+
+static int instance_unit_from_cgroup(char *cgroup){
+        char *at;
+
+        assert(cgroup);
+
+        at = strstr(cgroup, "@.");
+        if (at) {
+                /* This is a templated service */
+
+                char *i;
+                char _cleanup_free_ *i2 = NULL, *s = NULL;
+
+                i = strchr(at, '/');
+                if (!i || !i[1]) /* disallow empty instances */
+                        return -EINVAL;
+
+                s = strndup(at + 1, i - at - 1);
+                i2 = strdup(i + 1);
+                if (!s || !i2)
+                        return -ENOMEM;
+
+                strcpy(at + 1, i2);
+                strcat(at + 1, s);
+        }
+
+        return 0;
+}
+
+/* non-static only for testing purposes */
+int cgroup_to_unit(char *cgroup, char **unit){
+        int r;
+        char *p;
+
+        assert(cgroup);
+        assert(unit);
+
+        r = instance_unit_from_cgroup(cgroup);
+        if (r < 0)
+                return r;
+
+        p = strrchr(cgroup, '/');
+        assert(p);
+
+        r = unit_name_is_valid(p + 1, true);
+        if (!r)
+                return -EINVAL;
+
+        *unit = strdup(p + 1);
+        if (!*unit)
+                return -ENOMEM;
+
+        return 0;
+}
+
+static int cg_pid_get(const char *prefix, pid_t pid, char **unit) {
+        int r;
+        char _cleanup_free_ *cgroup = NULL;
+
+        assert(pid >= 0);
+        assert(unit);
+
+        r = cg_pid_get_cgroup(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
+
+        if (!startswith(cgroup, prefix))
+                return -ENOENT;
+
+        r = cgroup_to_unit(cgroup, unit);
+        return r;
+}
+
+int cg_pid_get_unit(pid_t pid, char **unit) {
+        return cg_pid_get("/system/", pid, unit);
+}
+
+int cg_pid_get_user_unit(pid_t pid, char **unit) {
+        return cg_pid_get("/user/", pid, unit);
+}
+
+int cg_controller_from_attr(const char *attr, char **controller) {
+        const char *dot;
+        char *c;
+
+        assert(attr);
+        assert(controller);
+
+        if (!filename_is_safe(attr))
+                return -EINVAL;
+
+        dot = strchr(attr, '.');
+        if (!dot) {
+                *controller = NULL;
+                return 0;
+        }
+
+        c = strndup(attr, dot - attr);
+        if (!c)
+                return -ENOMEM;
+
+        if (!filename_is_safe(c)) {
+                free(c);
+                return -EINVAL;
+        }
+
+        *controller = c;
+        return 1;
+}