X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fcgroup-util.c;h=8d3bdce0f576fa2184cf317e4758259b1e22a9e2;hb=e9d21f240704f87c6bb5f7fca1c5e6d0f31c84cd;hp=b2fb324a18c995255e954ff2bc5e644c5d8f0ba9;hpb=3474ae3c7e1981301d0b35bc89d759ca13f06e8f;p=elogind.git

diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
index b2fb324a1..8d3bdce0f 100644
--- a/src/shared/cgroup-util.c
+++ b/src/shared/cgroup-util.c
@@ -34,17 +34,19 @@
 #include "set.h"
 #include "macro.h"
 #include "util.h"
+#include "path-util.h"
+#include "strv.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 +64,11 @@ 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 +108,13 @@ 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);
@@ -513,16 +515,26 @@ 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 = 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);
+        } else {
+                if (path && suffix)
+                        t = join(path, "/", suffix, NULL);
+                else if (path)
+                        t = strdup(path);
+        }
 
         if (!t)
                 return -ENOMEM;
@@ -537,12 +549,8 @@ 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 +562,27 @@ 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 +590,13 @@ 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);
 }
@@ -653,7 +674,7 @@ 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);
@@ -883,20 +904,22 @@ 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;
@@ -916,13 +939,14 @@ int cg_is_empty_recursive(const char *controller, const char *path, bool ignore_
         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) {
@@ -1042,11 +1066,11 @@ 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 +1078,8 @@ 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 +1116,36 @@ 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;
+}