1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28#include <unistd.h>
29#include <stdio.h>
30#include <errno.h>
31#include <sys/stat.h>
32#include "cpuacct.h"
33#include <fcntl.h>
34
35int cpuacct_add(uid_t uid)
36{
37    int count;
38    int fd;
39    char buf[80];
40    ssize_t n;
41    int ret = 0;
42
43    count = snprintf(buf, sizeof(buf), "/acct/uid/%d/tasks", uid);
44    fd = open(buf, O_RDWR | O_CREAT, 0666);
45    if (fd == -1) {
46        /* Note: sizeof("tasks") returns 6, which includes the NULL char */
47        buf[count - sizeof("tasks")] = 0;
48        if (mkdir(buf, 0775) < 0)
49            return -errno;
50
51        /* Note: sizeof("tasks") returns 6, which includes the NULL char */
52        buf[count - sizeof("tasks")] = '/';
53        fd = open(buf, O_RDWR | O_CREAT, 0666);
54    }
55    if (fd == -1)
56        return -errno;
57
58    n = TEMP_FAILURE_RETRY(write(fd, "0", 1));
59    if (n < 0)
60        ret = -errno;
61    else if (n == 0)
62        ret = -EIO;
63
64    if (TEMP_FAILURE_RETRY(close(fd)) == -1)
65        return -errno;
66
67    return ret;
68}
69