1 /*
2 * Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of version 2 of the GNU General Public License as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it would be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11 *
12 * Further, this software is distributed without any warranty that it is
13 * free of the rightful claim of any third person regarding infringement
14 * or the like. Any license provided herein, whether implied or
15 * otherwise, applies only to this software file. Patent licenses, if
16 * any, provided herein do not apply to combinations of this program with
17 * other software, or any other product whatsoever.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
22 *
23 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24 * Mountain View, CA 94043, or:
25 *
26 * http://www.sgi.com
27 *
28 * For further information regarding this notice, see:
29 *
30 * http://oss.sgi.com/projects/GenInfo/NoticeExplan/
31 */
32
33 /* $Id: rmobj.c,v 1.5 2009/07/20 10:59:32 vapier Exp $ */
34
35 /**********************************************************
36 *
37 * OS Testing - Silicon Graphics, Inc.
38 *
39 * FUNCTION NAME : rmobj()
40 *
41 * FUNCTION TITLE : Remove an object
42 *
43 * SYNOPSIS:
44 * int rmobj(char *obj, char **errmsg)
45 *
46 * AUTHOR : Kent Rogers
47 *
48 * INITIAL RELEASE : UNICOS 7.0
49 *
50 * USER DESCRIPTION
51 * This routine will remove the specified object. If the specified
52 * object is a directory, it will recursively remove the directory
53 * and everything underneath it. It assumes that it has privilege
54 * to remove everything that it tries to remove. If rmobj() encounters
55 * any problems, and errmsg is not NULL, errmsg is set to point to a
56 * string explaining the error.
57 *
58 * DETAILED DESCRIPTION
59 * Allocate space for the directory and its contents
60 * Open the directory to get access to what is in it
61 * Loop through the objects in the directory:
62 * If the object is not "." or "..":
63 * Determine the file type by calling lstat()
64 * If the object is not a directory:
65 * Remove the object with unlink()
66 * Else:
67 * Call rmobj(object) to remove the object's contents
68 * Determine the link count on object by calling lstat()
69 * If the link count >= 3:
70 * Remove the directory with unlink()
71 * Else
72 * Remove the directory with rmdir()
73 * Close the directory and free the pointers
74 *
75 * RETURN VALUE
76 * If there are any problems, rmobj() will set errmsg (if it was not
77 * NULL) and return -1. Otherwise it will return 0.
78 *
79 ************************************************************/
80 #define _GNU_SOURCE
81 #include <errno.h> /* for errno */
82 #include <stdio.h> /* for NULL */
83 #include <stdlib.h> /* for malloc() */
84 #include <string.h> /* for string function */
85 #include <limits.h> /* for PATH_MAX */
86 #include <sys/types.h> /* for opendir(), readdir(), closedir(), stat() */
87 #include <sys/stat.h> /* for [l]stat() */
88 #include <fcntl.h>
89 #include <dirent.h> /* for opendir(), readdir(), closedir() */
90 #include <unistd.h> /* for rmdir(), unlink() */
91 #include "rmobj.h"
92
93 #define SYSERR strerror(errno)
94
rmobj(char * obj,char ** errmsg)95 int rmobj(char *obj, char **errmsg)
96 {
97 int ret_val = 0; /* return value from this routine */
98 DIR *dir; /* pointer to a directory */
99 struct dirent *dir_ent; /* pointer to directory entries */
100 char dirobj[PATH_MAX]; /* object inside directory to modify */
101 struct stat statbuf; /* used to hold stat information */
102 static char err_msg[1024]; /* error message */
103 int fd;
104
105 /* Determine the file type */
106
107 fd = open(obj, O_DIRECTORY | O_NOFOLLOW);
108 if (fd != -1) {
109 close(fd);
110 /* object is a directory */
111
112 /* Do NOT perform the request if the directory is "/" */
113 if (!strcmp(obj, "/")) {
114 if (errmsg != NULL) {
115 sprintf(err_msg, "Cannot remove /");
116 *errmsg = err_msg;
117 }
118 return -1;
119 }
120
121 /* Open the directory to get access to what is in it */
122 if ((dir = opendir(obj)) == NULL) {
123 if (rmdir(obj) != 0) {
124 if (errmsg != NULL) {
125 sprintf(err_msg,
126 "rmdir(%s) failed; errno=%d: %s",
127 obj, errno, SYSERR);
128 *errmsg = err_msg;
129 }
130 return -1;
131 } else {
132 return 0;
133 }
134 }
135
136 /* Loop through the entries in the directory, removing each one */
137 for (dir_ent = (struct dirent *)readdir(dir);
138 dir_ent != NULL; dir_ent = (struct dirent *)readdir(dir)) {
139
140 /* Don't remove "." or ".." */
141 if (!strcmp(dir_ent->d_name, ".")
142 || !strcmp(dir_ent->d_name, ".."))
143 continue;
144
145 /* Recursively call this routine to remove the current entry */
146 sprintf(dirobj, "%s/%s", obj, dir_ent->d_name);
147 if (rmobj(dirobj, errmsg) != 0)
148 ret_val = -1;
149 }
150
151 /* Close the directory */
152 closedir(dir);
153
154 /* If there were problems removing an entry, don't attempt to
155 remove the directory itself */
156 if (ret_val == -1)
157 return -1;
158
159 /* Get the link count, now that all the entries have been removed */
160 if (lstat(obj, &statbuf) < 0) {
161 if (errmsg != NULL) {
162 sprintf(err_msg,
163 "lstat(%s) failed; errno=%d: %s", obj,
164 errno, SYSERR);
165 *errmsg = err_msg;
166 }
167 return -1;
168 }
169
170 /* Remove the directory itself */
171 if (statbuf.st_nlink >= 3) {
172 /* The directory is linked; unlink() must be used */
173 if (unlink(obj) < 0) {
174 if (errmsg != NULL) {
175 sprintf(err_msg,
176 "unlink(%s) failed; errno=%d: %s",
177 obj, errno, SYSERR);
178 *errmsg = err_msg;
179 }
180 return -1;
181 }
182 } else {
183 /* The directory is not linked; remove() can be used */
184 if (remove(obj) < 0) {
185 if (errmsg != NULL) {
186 sprintf(err_msg,
187 "remove(%s) failed; errno=%d: %s",
188 obj, errno, SYSERR);
189 *errmsg = err_msg;
190 }
191 return -1;
192 }
193 }
194 } else {
195 /* object is not a directory; just use unlink() */
196 if (unlink(obj) < 0) {
197 if (errmsg != NULL) {
198 sprintf(err_msg,
199 "unlink(%s) failed; errno=%d: %s", obj,
200 errno, SYSERR);
201 *errmsg = err_msg;
202 }
203 return -1;
204 }
205 } /* if obj is a directory */
206
207 /*
208 * Everything must have went ok.
209 */
210 return 0;
211 } /* rmobj() */
212