| /****************************************************************************** |
| * |
| * Copyright (C) 2016 Google, Inc. |
| * |
| * Licensed 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. |
| * |
| ******************************************************************************/ |
| |
| #define LOG_TAG "bt_osi_rand" |
| |
| #include <assert.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <unistd.h> |
| |
| #include "osi/include/log.h" |
| #include "osi/include/osi.h" |
| |
| #define RANDOM_PATH "/dev/urandom" |
| |
| int osi_rand(void) { |
| int rand; |
| int rand_fd = open(RANDOM_PATH, O_RDONLY); |
| |
| if (rand_fd == INVALID_FD) { |
| LOG_ERROR(LOG_TAG, "%s can't open rand fd %s: %s ", __func__, RANDOM_PATH, |
| strerror(errno)); |
| assert(0); |
| } |
| |
| ssize_t read_bytes = read(rand_fd, &rand, sizeof(rand)); |
| close(rand_fd); |
| |
| assert(read_bytes == sizeof(rand)); |
| |
| if (rand < 0) |
| rand = -rand; |
| |
| return rand; |
| } |