| /**************************************************************************** |
| * libs/libc/unistd/lib_getpriority.c |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. The |
| * ASF licenses this file to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance with the |
| * License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations |
| * under the License. |
| * |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Included Files |
| ****************************************************************************/ |
| |
| #include <nuttx/config.h> |
| #include <sys/resource.h> |
| |
| #include <sched.h> |
| #include <unistd.h> |
| #include <errno.h> |
| |
| #include <nuttx/sched.h> |
| |
| /**************************************************************************** |
| * Public Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Name: getpriority |
| * |
| * Description: |
| * The getpriority() function shall obtain the nice value of a process, |
| * process group, or user. |
| * |
| * Input Parameters: |
| * which - PRIO_PROCESS, PRIO_PGRP, or PRIO_USER, ignored in current |
| * implementation. |
| * who - Process id is interpreted relative to "which" |
| * |
| * Returned Value: |
| * Upon successful completion, getpriority() shall return an integer in |
| * the range -{NZERO} to {NZERO}-1. Otherwise, -1 shall be returned and |
| * errno set to indicate the error. The following errors may be |
| * reported: |
| * |
| * - ESRCH: No process was located using the which and who values |
| * specified. |
| * - EINVAL: which was not one of PRIO_PROCESS, PRIO_PGRP, or |
| * PRIO_USER. |
| * |
| * Assumptions: |
| * |
| ****************************************************************************/ |
| |
| int getpriority(int which, id_t who) |
| { |
| struct sched_param param; |
| int ret; |
| |
| if (which > PRIO_USER || which < PRIO_PROCESS) |
| { |
| set_errno(EINVAL); |
| return ERROR; |
| } |
| |
| if (who == 0) |
| { |
| who = _SCHED_GETTID(); |
| } |
| |
| ret = sched_getparam(who, ¶m); |
| if (ret < 0) |
| { |
| return ret; |
| } |
| |
| /* Since -1 is a legal return value, clear errno to avoid the chaos */ |
| |
| set_errno(0); |
| |
| return NZERO - param.sched_priority; |
| } |