*len = newlen;
}
-static char *slurp_file(const char *from)
+static char *slurp_file(const char *from, int fd)
{
char *line = NULL;
char *contents = NULL;
- FILE *f = fopen(from, "r");
+ FILE *f = fdopen(fd, "r");
size_t len = 0, fulllen = 0;
ssize_t linelen;
return true;
}
-/*
- * hierarchies, i.e. 'cpu,cpuacct'
- */
-char **hierarchies;
-int num_hierarchies;
-
struct cgfs_files {
char *name;
uint32_t uid, gid;
{
int i;
- fprintf(stderr, "hierarchies:");
+ fprintf(stderr, "hierarchies:\n");
for (i = 0; i < num_hierarchies; i++) {
if (hierarchies[i])
fprintf(stderr, " %d: %s\n", i, hierarchies[i]);
}
/* do we need to do any massaging here? I'm not sure... */
-static char *find_mounted_controller(const char *controller)
+/* Return the mounted controller and store the corresponding open file descriptor
+ * referring to the controller mountpoint in the private lxcfs namespace in
+ * @cfd.
+ */
+static char *find_mounted_controller(const char *controller, int *cfd)
{
int i;
for (i = 0; i < num_hierarchies; i++) {
if (!hierarchies[i])
continue;
- if (strcmp(hierarchies[i], controller) == 0)
+ if (strcmp(hierarchies[i], controller) == 0) {
+ *cfd = fd_hierarchies[i];
return hierarchies[i];
- if (in_comma_list(controller, hierarchies[i]))
+ }
+ if (in_comma_list(controller, hierarchies[i])) {
+ *cfd = fd_hierarchies[i];
return hierarchies[i];
+ }
}
return NULL;
bool cgfs_set_value(const char *controller, const char *cgroup, const char *file,
const char *value)
{
+ int cfd;
size_t len;
- char *fnam, *tmpc = find_mounted_controller(controller);
+ char *fnam, *tmpc = find_mounted_controller(controller, &cfd);
if (!tmpc)
return false;
- /* basedir / tmpc / cgroup / file \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cgroup) + strlen(file) + 4;
+ /* BASEDIR / tmpc / cgroup / file \0 */
+ len = strlen(BASEDIR) + strlen(tmpc) + strlen(cgroup) + strlen(file) + 4;
fnam = alloca(len);
- snprintf(fnam, len, "%s/%s/%s/%s", basedir, tmpc, cgroup, file);
+ snprintf(fnam, len, "%s/%s/%s/%s", BASEDIR, tmpc, cgroup, file);
return write_string(fnam, value);
}
int cgfs_create(const char *controller, const char *cg, uid_t uid, gid_t gid)
{
+ int cfd;
size_t len;
- char *dirnam, *tmpc = find_mounted_controller(controller);
+ char *dirnam, *tmpc = find_mounted_controller(controller, &cfd);
if (!tmpc)
return -EINVAL;
- /* basedir / tmpc / cg \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cg) + 3;
+ /* BASEDIR / tmpc / cg \0 */
+ len = strlen(BASEDIR) + strlen(tmpc) + strlen(cg) + 3;
dirnam = alloca(len);
- snprintf(dirnam, len, "%s/%s/%s", basedir,tmpc, cg);
+ snprintf(dirnam, len, "%s/%s/%s", BASEDIR,tmpc, cg);
if (mkdir(dirnam, 0755) < 0)
return -errno;
bool cgfs_remove(const char *controller, const char *cg)
{
+ int cfd;
size_t len;
- char *dirnam, *tmpc = find_mounted_controller(controller);
+ char *dirnam, *tmpc = find_mounted_controller(controller, &cfd);
if (!tmpc)
return false;
- /* basedir / tmpc / cg \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cg) + 3;
+ /* BASEDIR / tmpc / cg \0 */
+ len = strlen(BASEDIR) + strlen(tmpc) + strlen(cg) + 3;
dirnam = alloca(len);
- snprintf(dirnam, len, "%s/%s/%s", basedir,tmpc, cg);
+ snprintf(dirnam, len, "%s/%s/%s", BASEDIR,tmpc, cg);
return recursive_rmdir(dirnam);
}
bool cgfs_chmod_file(const char *controller, const char *file, mode_t mode)
{
+ int cfd;
size_t len;
- char *pathname, *tmpc = find_mounted_controller(controller);
+ char *pathname, *tmpc = find_mounted_controller(controller, &cfd);
if (!tmpc)
return false;
- /* basedir / tmpc / file \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(file) + 3;
+ /* BASEDIR / tmpc / file \0 */
+ len = strlen(BASEDIR) + strlen(tmpc) + strlen(file) + 3;
pathname = alloca(len);
- snprintf(pathname, len, "%s/%s/%s", basedir, tmpc, file);
+ snprintf(pathname, len, "%s/%s/%s", BASEDIR, tmpc, file);
if (chmod(pathname, mode) < 0)
return false;
return true;
int cgfs_chown_file(const char *controller, const char *file, uid_t uid, gid_t gid)
{
+ int cfd;
size_t len;
- char *pathname, *tmpc = find_mounted_controller(controller);
+ char *pathname, *tmpc = find_mounted_controller(controller, &cfd);
if (!tmpc)
return -EINVAL;
- /* basedir / tmpc / file \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(file) + 3;
+ /* BASEDIR / tmpc / file \0 */
+ len = strlen(BASEDIR) + strlen(tmpc) + strlen(file) + 3;
pathname = alloca(len);
- snprintf(pathname, len, "%s/%s/%s", basedir, tmpc, file);
+ snprintf(pathname, len, "%s/%s/%s", BASEDIR, tmpc, file);
if (chown(pathname, uid, gid) < 0)
return -errno;
FILE *open_pids_file(const char *controller, const char *cgroup)
{
+ int cfd;
size_t len;
- char *pathname, *tmpc = find_mounted_controller(controller);
+ char *pathname, *tmpc = find_mounted_controller(controller, &cfd);
if (!tmpc)
return NULL;
- /* basedir / tmpc / cgroup / "cgroup.procs" \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cgroup) + 4 + strlen("cgroup.procs");
+ /* BASEDIR / tmpc / cgroup / "cgroup.procs" \0 */
+ len = strlen(BASEDIR) + strlen(tmpc) + strlen(cgroup) + 4 + strlen("cgroup.procs");
pathname = alloca(len);
- snprintf(pathname, len, "%s/%s/%s/cgroup.procs", basedir, tmpc, cgroup);
+ snprintf(pathname, len, "%s/%s/%s/cgroup.procs", BASEDIR, tmpc, cgroup);
return fopen(pathname, "w");
}
void ***list, size_t typesize,
void* (*iterator)(const char*, const char*, const char*))
{
+ int cfd, fd, ret;
size_t len;
- char *dirname, *tmpc = find_mounted_controller(controller);
+ char *cg, *tmpc;
char pathname[MAXPATHLEN];
size_t sz = 0, asz = 0;
- struct dirent dirent, *direntp;
+ struct dirent *dirent;
DIR *dir;
- int ret;
+ tmpc = find_mounted_controller(controller, &cfd);
*list = NULL;
if (!tmpc)
return false;
- /* basedir / tmpc / cgroup \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cgroup) + 3;
- dirname = alloca(len);
- snprintf(dirname, len, "%s/%s/%s", basedir, tmpc, cgroup);
+ /* Make sure we pass a relative path to openat(). */
+ len = strlen(cgroup) + 1 /* . */ + 1 /* \0 */;
+ cg = alloca(len);
+ ret = snprintf(cg, len, "%s%s", *cgroup == '/' ? "." : "", cgroup);
+ if (ret < 0 || (size_t)ret >= len) {
+ fprintf(stderr, "%s: pathname too long under %s\n", __func__, cgroup);
+ return false;
+ }
- dir = opendir(dirname);
+ fd = openat(cfd, cg, O_DIRECTORY);
+ if (fd < 0)
+ return false;
+
+ dir = fdopendir(fd);
if (!dir)
return false;
- while (!readdir_r(dir, &dirent, &direntp)) {
+ while ((dirent = readdir(dir))) {
struct stat mystat;
- int rc;
-
- if (!direntp)
- break;
- if (!strcmp(direntp->d_name, ".") ||
- !strcmp(direntp->d_name, ".."))
+ if (!strcmp(dirent->d_name, ".") ||
+ !strcmp(dirent->d_name, ".."))
continue;
- rc = snprintf(pathname, MAXPATHLEN, "%s/%s", dirname, direntp->d_name);
- if (rc < 0 || rc >= MAXPATHLEN) {
- fprintf(stderr, "%s: pathname too long under %s\n", __func__, dirname);
+ ret = snprintf(pathname, MAXPATHLEN, "%s/%s", cg, dirent->d_name);
+ if (ret < 0 || ret >= MAXPATHLEN) {
+ fprintf(stderr, "%s: pathname too long under %s\n", __func__, cg);
continue;
}
- ret = lstat(pathname, &mystat);
+ ret = fstatat(cfd, pathname, &mystat, AT_SYMLINK_NOFOLLOW);
if (ret) {
fprintf(stderr, "%s: failed to stat %s: %s\n", __func__, pathname, strerror(errno));
continue;
} while (!tmp);
*list = tmp;
}
- (*list)[sz] = (*iterator)(controller, cgroup, direntp->d_name);
+ (*list)[sz] = (*iterator)(controller, cg, dirent->d_name);
(*list)[sz+1] = NULL;
sz++;
}
if (closedir(dir) < 0) {
- fprintf(stderr, "%s: failed closedir for %s: %s\n", __func__, dirname, strerror(errno));
+ fprintf(stderr, "%s: failed closedir for %s: %s\n", __func__, cgroup, strerror(errno));
return false;
}
return true;
bool cgfs_get_value(const char *controller, const char *cgroup, const char *file, char **value)
{
+ int ret, fd, cfd;
size_t len;
- char *fnam, *tmpc = find_mounted_controller(controller);
+ char *fnam, *tmpc = find_mounted_controller(controller, &cfd);
if (!tmpc)
return false;
- /* basedir / tmpc / cgroup / file \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cgroup) + strlen(file) + 4;
+ /* . + /cgroup + / + file + \0 */
+ len = strlen(cgroup) + strlen(file) + 3;
fnam = alloca(len);
- snprintf(fnam, len, "%s/%s/%s/%s", basedir, tmpc, cgroup, file);
+ ret = snprintf(fnam, len, "%s%s/%s", *cgroup == '/' ? "." : "", cgroup, file);
+ if (ret < 0 || (size_t)ret >= len)
+ return NULL;
+
+ fd = openat(cfd, fnam, O_RDONLY);
+ if (fd < 0)
+ return NULL;
- *value = slurp_file(fnam);
+ *value = slurp_file(fnam, fd);
return *value != NULL;
}
struct cgfs_files *cgfs_get_key(const char *controller, const char *cgroup, const char *file)
{
+ int ret, cfd;
size_t len;
- char *fnam, *tmpc = find_mounted_controller(controller);
+ char *fnam, *tmpc = find_mounted_controller(controller, &cfd);
struct stat sb;
struct cgfs_files *newkey;
- int ret;
if (!tmpc)
return false;
if (file && index(file, '/'))
return NULL;
- /* basedir / tmpc / cgroup / file \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cgroup) + 3;
+ /* . + /cgroup + / + file + \0 */
+ len = strlen(cgroup) + 3;
if (file)
len += strlen(file) + 1;
fnam = alloca(len);
- snprintf(fnam, len, "%s/%s/%s%s%s", basedir, tmpc, cgroup,
- file ? "/" : "", file ? file : "");
+ snprintf(fnam, len, "%s%s%s%s", *cgroup == '/' ? "." : "", cgroup,
+ file ? "/" : "", file ? file : "");
- ret = stat(fnam, &sb);
+ ret = fstatat(cfd, fnam, &sb, 0);
if (ret < 0)
return NULL;
}
bool is_child_cgroup(const char *controller, const char *cgroup, const char *f)
-{ size_t len;
- char *fnam, *tmpc = find_mounted_controller(controller);
+{
+ int cfd;
+ size_t len;
+ char *fnam, *tmpc = find_mounted_controller(controller, &cfd);
int ret;
struct stat sb;
if (!tmpc)
return false;
- /* basedir / tmpc / cgroup / f \0 */
- len = strlen(basedir) + strlen(tmpc) + strlen(cgroup) + strlen(f) + 4;
+ /* . + /cgroup + / + f + \0 */
+ len = strlen(cgroup) + strlen(f) + 3;
fnam = alloca(len);
- snprintf(fnam, len, "%s/%s/%s/%s", basedir, tmpc, cgroup, f);
+ ret = snprintf(fnam, len, "%s%s/%s", *cgroup == '/' ? "." : "", cgroup, f);
+ if (ret < 0 || (size_t)ret >= len)
+ return false;
- ret = stat(fnam, &sb);
+ ret = fstatat(cfd, fnam, &sb, 0);
if (ret < 0 || !S_ISDIR(sb.st_mode))
return false;
return true;
static char *get_pid_cgroup(pid_t pid, const char *contrl)
{
+ int cfd;
char fnam[PROCLEN];
FILE *f;
char *answer = NULL;
char *line = NULL;
size_t len = 0;
int ret;
- const char *h = find_mounted_controller(contrl);
+ const char *h = find_mounted_controller(contrl, &cfd);
if (!h)
return NULL;
prune_init_slice(c2);
/*
- * callers pass in '/' for root cgroup, otherwise they pass
- * in a cgroup without leading '/'
+ * callers pass in '/' or './' (openat()) for root cgroup, otherwise
+ * they pass in a cgroup without leading '/'
+ *
+ * The original line here was:
+ * linecmp = *cg == '/' ? c2 : c2+1;
+ * TODO: I'm not sure why you'd want to increment when *cg != '/'?
+ * Serge, do you know?
*/
- linecmp = *cg == '/' ? c2 : c2+1;
+ if (*cg == '/' || !strncmp(cg, "./", 2))
+ linecmp = c2;
+ else
+ linecmp = c2 + 1;
if (strncmp(linecmp, cg, strlen(linecmp)) != 0) {
if (nextcg) {
*nextcg = get_next_cgroup_dir(linecmp, cg);
char *c2, *task_cg;
size_t target_len, task_len;
- if (strcmp(cg, "/") == 0)
+ if (strcmp(cg, "/") == 0 || strcmp(cg, "./") == 0)
return true;
c2 = get_pid_cgroup(pid, contrl);
projects / mirror_lxcfs.git / blobdiff