1/*
2 *
3 * Copyright (C) 2008, The Android Open Source Project
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18#include <dirent.h>
19#include <fcntl.h>
20#include <sys/stat.h>
21#include <unistd.h>
22
23#include <diskusage/dirsize.h>
24
25int64_t stat_size(struct stat *s)
26{
27    int64_t blksize = s->st_blksize;
28    // count actual blocks used instead of nominal file size
29    int64_t size = s->st_blocks * 512;
30
31    if (blksize) {
32        /* round up to filesystem block size */
33        size = (size + blksize - 1) & (~(blksize - 1));
34    }
35
36    return size;
37}
38
39int64_t calculate_dir_size(int dfd)
40{
41    int64_t size = 0;
42    struct stat s;
43    DIR *d;
44    struct dirent *de;
45
46    d = fdopendir(dfd);
47    if (d == NULL) {
48        close(dfd);
49        return 0;
50    }
51
52    while ((de = readdir(d))) {
53        const char *name = de->d_name;
54        if (fstatat(dfd, name, &s, AT_SYMLINK_NOFOLLOW) == 0) {
55            size += stat_size(&s);
56        }
57        if (de->d_type == DT_DIR) {
58            int subfd;
59
60            /* always skip "." and ".." */
61            if (name[0] == '.') {
62                if (name[1] == 0)
63                    continue;
64                if ((name[1] == '.') && (name[2] == 0))
65                    continue;
66            }
67
68            subfd = openat(dfd, name, O_RDONLY | O_DIRECTORY);
69            if (subfd >= 0) {
70                size += calculate_dir_size(subfd);
71            }
72        }
73    }
74    closedir(d);
75    return size;
76}
77