1 files changed, 174 insertions, 0 deletions
diff --git a/src/nxt_cgroup.c b/src/nxt_cgroup.c
new file mode 100644
index 00000000..2c404acc
--- /dev/null
+++ b/src/nxt_cgroup.c
@@ -0,0 +1,174 @@
+/*
+ * Copyright (C) Andrew Clayton
+ * Copyright (C) F5, Inc.
+ */
+
+#include <nxt_main.h>
+
+#include <nxt_cgroup.h>
+
+
+static int nxt_mk_cgpath_relative(nxt_task_t *task, const char *dir,
+    char *cgpath);
+static nxt_int_t nxt_mk_cgpath(nxt_task_t *task, const char *dir,
+    char *cgpath);
+
+
+nxt_int_t
+nxt_cgroup_proc_add(nxt_task_t *task, nxt_process_t *process)
+{
+    int        len;
+    char       cgprocs[NXT_MAX_PATH_LEN];
+    FILE       *fp;
+    nxt_int_t  ret;
+
+    if (task->thread->runtime->type != NXT_PROCESS_MAIN
+        || nxt_process_type(process) != NXT_PROCESS_PROTOTYPE
+        || process->isolation.cgroup.path == NULL)
+    {
+        return NXT_OK;
+    }
+
+    ret = nxt_mk_cgpath(task, process->isolation.cgroup.path, cgprocs);
+    if (nxt_slow_path(ret == NXT_ERROR)) {
+        return NXT_ERROR;
+    }
+
+    ret = nxt_fs_mkdir_all((const u_char *) cgprocs, 0777);
+    if (nxt_slow_path(ret == NXT_ERROR)) {
+        return NXT_ERROR;
+    }
+
+    len = strlen(cgprocs);
+
+    len = snprintf(cgprocs + len, NXT_MAX_PATH_LEN - len, "/cgroup.procs");
+    if (nxt_slow_path(len >= NXT_MAX_PATH_LEN - len)) {
+        nxt_errno = ENAMETOOLONG;
+        return NXT_ERROR;
+    }
+
+    fp = nxt_file_fopen(task, cgprocs, "we");
+    if (nxt_slow_path(fp == NULL)) {
+        return NXT_ERROR;
+    }
+
+    setvbuf(fp, NULL, _IONBF, 0);
+    len = fprintf(fp, "%d\n", process->pid);
+    nxt_file_fclose(task, fp);
+
+    if (nxt_slow_path(len < 0)) {
+        return NXT_ERROR;
+    }
+
+    return NXT_OK;
+}
+
+
+void
+nxt_cgroup_cleanup(nxt_task_t *task, const nxt_process_t *process)
+{
+    char       *ptr;
+    char       cgroot[NXT_MAX_PATH_LEN], cgpath[NXT_MAX_PATH_LEN];
+    nxt_int_t  ret;
+
+    ret = nxt_mk_cgpath(task, "", cgroot);
+    if (nxt_slow_path(ret == NXT_ERROR)) {
+        return;
+    }
+
+    ret = nxt_mk_cgpath(task, process->isolation.cgroup.path, cgpath);
+    if (nxt_slow_path(ret == NXT_ERROR)) {
+        return;
+    }
+
+    while (*cgpath != '\0' && strcmp(cgroot, cgpath) != 0) {
+        rmdir(cgpath);
+        ptr = strrchr(cgpath, '/');
+        *ptr = '\0';
+    }
+}
+
+
+static int
+nxt_mk_cgpath_relative(nxt_task_t *task, const char *dir, char *cgpath)
+{
+    int         i, len;
+    char        *buf, *ptr;
+    FILE        *fp;
+    size_t      size;
+    ssize_t     nread;
+    nxt_bool_t  found;
+
+    fp = nxt_file_fopen(task, "/proc/self/cgroup", "re");
+    if (nxt_slow_path(fp == NULL)) {
+        return -1;
+    }
+
+    len = -1;
+    buf = NULL;
+    found = 0;
+    while ((nread = getline(&buf, &size, fp)) != -1) {
+        if (strncmp(buf, "0::", 3) == 0) {
+            found = 1;
+            break;
+        }
+    }
+
+    nxt_file_fclose(task, fp);
+
+    if (!found) {
+        nxt_errno = ENODATA;
+        goto out_free_buf;
+    }
+
+    buf[nread - 1] = '\0';  /* lose the trailing '\n' */
+    ptr = buf;
+    for (i = 0; i < 2; i++) {
+        ptr = strchr(ptr, ':');
+        if (ptr == NULL) {
+            nxt_errno = ENODATA;
+            goto out_free_buf;
+        }
+
+        ptr++;
+    }
+
+    len = snprintf(cgpath, NXT_MAX_PATH_LEN, NXT_CGROUP_ROOT "%s/%s",
+                   ptr, dir);
+
+out_free_buf:
+
+    nxt_free(buf);
+
+    return len;
+}
+
+
+static nxt_int_t
+nxt_mk_cgpath(nxt_task_t *task, const char *dir, char *cgpath)
+{
+    int  len;
+
+    /*
+     * If the path from the config is relative, we need to make
+     * the cgroup path include the main unit processes cgroup. I.e
+     *
+     *   NXT_CGROUP_ROOT/<main process cgroup>/<cgroup path>
+     */
+    if (dir[0] != '/') {
+        len = nxt_mk_cgpath_relative(task, dir, cgpath);
+    } else {
+        len = snprintf(cgpath, NXT_MAX_PATH_LEN, NXT_CGROUP_ROOT "%s", dir);
+    }
+
+    if (len == -1) {
+        return NXT_ERROR;
+    }
+
+    if (len >= NXT_MAX_PATH_LEN) {
+        nxt_errno = ENAMETOOLONG;
+        return NXT_ERROR;
+    }
+
+    return NXT_OK;
+}