1 /******************************************************************************/
2 /* */
3 /* Copyright (c) 2009 FUJITSU LIMITED */
4 /* */
5 /* This program is free software; you can redistribute it and/or modify */
6 /* it under the terms of the GNU General Public License as published by */
7 /* the Free Software Foundation; either version 2 of the License, or */
8 /* (at your option) any later version. */
9 /* */
10 /* This program is distributed in the hope that it will be useful, */
11 /* but WITHOUT ANY WARRANTY; without even the implied warranty of */
12 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */
13 /* the GNU General Public License for more details. */
14 /* */
15 /* You should have received a copy of the GNU General Public License */
16 /* along with this program; if not, write to the Free Software */
17 /* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
18 /* */
19 /* Author: Li Zefan <lizf@cn.fujitsu.com> */
20 /* */
21 /******************************************************************************/
22
23 #define _ATFILE_SOURCE
24 #include <unistd.h>
25 #include <stdlib.h>
26 #include <stdio.h>
27 #include <errno.h>
28 #include <fcntl.h>
29 #include <sys/stat.h>
30 #include <sys/types.h>
31 #include "config.h"
32
33 /* valid characters for a directory name */
34 char chars[] = "0123456789qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM";
35
36 /* to store the generated directory name */
37 char name[10];
38 int names;
39 int parent_fd;
40
41 /* NCHARS = 10 + 26 + 26 = 62 */
42 #define NCHARS 62
43 #define MAX_LEN1 62
44 #define MAX_LEN2 (62 * 62)
45 #define MAX_LEN3 (62 * 62 * 62)
46 #define MAX_NAMES (MAX_LEN1 + MAX_LEN2 + MAX_LEN3)
47
create_dir(void)48 void create_dir(void)
49 {
50 #ifdef HAVE_MKDIRAT
51 if (mkdirat(parent_fd, name, S_IRWXU)) {
52 perror("mkdir");
53 exit(1);
54 }
55 #else
56 fprintf(stderr, "System lacks mkdirat() call.\n");
57 exit(1);
58 #endif
59 }
60
61 /*
62 * create_1 - create length-1 directory names
63 * @n: how name names to be created
64 */
create_1(int n)65 void create_1(int n)
66 {
67 int i;
68
69 name[1] = '\0';
70 for (i = 0; i < NCHARS; i++) {
71 name[0] = chars[i];
72 create_dir();
73 if (--n == 0)
74 return;
75 }
76 }
77
78 /*
79 * create_2 - generate length-2 directory names
80 * @n: how many names to be created
81 */
create_2(int n)82 void create_2(int n)
83 {
84 int i, j;
85
86 name[2] = '\0';
87 for (i = 0; i < NCHARS; i++) {
88 name[0] = chars[i];
89 for (j = 0; j < NCHARS; j++) {
90 name[1] = chars[j];
91 create_dir();
92 if (--n == 0)
93 return;
94 }
95 }
96 }
97
98 /*
99 * create_3 - generate length-3 directory names
100 * @n: how many names to be created
101 */
create_3(int n)102 void create_3(int n)
103 {
104 int i, j, k;
105
106 name[3] = '\0';
107 for (i = 0; i < NCHARS; i++) {
108 name[0] = chars[i];
109 for (j = 0; j < NCHARS; j++) {
110 name[1] = chars[j];
111 for (k = 0; k < NCHARS; k++) {
112 name[2] = chars[k];
113 create_dir();
114 if (--n == 0)
115 return;
116 }
117 }
118 }
119 }
120
usage()121 void usage()
122 {
123 fprintf(stderr, "Usage: create_short_dirs nr_dirs parent_dir\n");
124 }
125
126 /*
127 * Create short-name directoriess
128 * @argv[1]: director number
129 * @argv[2]: the parent directory
130 */
main(int argc,char * argv[])131 int main(int argc, char *argv[])
132 {
133 if (argc != 3) {
134 usage();
135 return 1;
136 }
137
138 names = atoi(argv[1]);
139 if (names > MAX_NAMES || names <= 0) {
140 usage();
141 return 1;
142 }
143
144 parent_fd = open(argv[2], O_RDONLY);
145 if (parent_fd == -1) {
146 perror("open parent dir");
147 return 1;
148 }
149
150 create_1(names);
151 if (names <= MAX_LEN1)
152 return 0;
153
154 names -= MAX_LEN1;
155 create_2(names);
156 if (names <= MAX_LEN2)
157 return 0;
158
159 names -= MAX_LEN2;
160 create_3(names);
161
162 return 0;
163 }
164