/*
* Copyright (C) 2007 The Android Open Source Project
*
* 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.
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <dirent.h>
#include <limits.h>
#include "DirUtil.h"
typedef enum { DMISSING, DDIR, DILLEGAL } DirStatus;
static DirStatus
getPathDirStatus(const char *path)
{
struct stat st;
int err;
err = stat(path, &st);
if (err == 0) {
/* Something's there; make sure it's a directory.
*/
if (S_ISDIR(st.st_mode)) {
return DDIR;
}
errno = ENOTDIR;
return DILLEGAL;
} else if (errno != ENOENT) {
/* Something went wrong, or something in the path
* is bad. Can't do anything in this situation.
*/
return DILLEGAL;
}
return DMISSING;
}
int
dirCreateHierarchy(const char *path, int mode,
const struct utimbuf *timestamp, bool stripFileName,
struct selabel_handle *sehnd)
{
DirStatus ds;
/* Check for an empty string before we bother
* making any syscalls.
*/
if (path[0] == '\0') {
errno = ENOENT;
return -1;
}
/* Allocate a path that we can modify; stick a slash on
* the end to make things easier.
*/
size_t pathLen = strlen(path);
char *cpath = (char *)malloc(pathLen + 2);
if (cpath == NULL) {
errno = ENOMEM;
return -1;
}
memcpy(cpath, path, pathLen);
if (stripFileName) {
/* Strip everything after the last slash.
*/
char *c = cpath + pathLen - 1;
while (c != cpath && *c != '/') {
c--;
}
if (c == cpath) {
//xxx test this path
/* No directory component. Act like the path was empty.
*/
errno = ENOENT;
free(cpath);
return -1;
}
c[1] = '\0'; // Terminate after the slash we found.
} else {
/* Make sure that the path ends in a slash.
*/
cpath[pathLen] = '/';
cpath[pathLen + 1] = '\0';
}
/* See if it already exists.
*/
ds = getPathDirStatus(cpath);
if (ds == DDIR) {
return 0;
} else if (ds == DILLEGAL) {
return -1;
}
/* Walk up the path from the root and make each level.
* If a directory already exists, no big deal.
*/
char *p = cpath;
while (*p != '\0') {
/* Skip any slashes, watching out for the end of the string.
*/
while (*p != '\0' && *p == '/') {
p++;
}
if (*p == '\0') {
break;
}
/* Find the end of the next path component.
* We know that we'll see a slash before the NUL,
* because we added it, above.
*/
while (*p != '/') {
p++;
}
*p = '\0';
/* Check this part of the path and make a new directory
* if necessary.
*/
ds = getPathDirStatus(cpath);
if (ds == DILLEGAL) {
/* Could happen if some other process/thread is
* messing with the filesystem.
*/
free(cpath);
return -1;
} else if (ds == DMISSING) {
int err;
#ifdef HAVE_SELINUX
char *secontext = NULL;
if (sehnd) {
selabel_lookup(sehnd, &secontext, cpath, mode);
setfscreatecon(secontext);
}
#endif
err = mkdir(cpath, mode);
#ifdef HAVE_SELINUX
if (secontext) {
freecon(secontext);
setfscreatecon(NULL);
}
#endif
if (err != 0) {
free(cpath);
return -1;
}
if (timestamp != NULL && utime(cpath, timestamp)) {
free(cpath);
return -1;
}
}
// else, this directory already exists.
/* Repair the path and continue.
*/
*p = '/';
}
free(cpath);
return 0;
}
int
dirUnlinkHierarchy(const char *path)
{
struct stat st;
DIR *dir;
struct dirent *de;
int fail = 0;
/* is it a file or directory? */
if (lstat(path, &st) < 0) {
return -1;
}
/* a file, so unlink it */
if (!S_ISDIR(st.st_mode)) {
return unlink(path);
}
/* a directory, so open handle */
dir = opendir(path);
if (dir == NULL) {
return -1;
}
/* recurse over components */
errno = 0;
while ((de = readdir(dir)) != NULL) {
//TODO: don't blow the stack
char dn[PATH_MAX];
if (!strcmp(de->d_name, "..") || !strcmp(de->d_name, ".")) {
continue;
}
snprintf(dn, sizeof(dn), "%s/%s", path, de->d_name);
if (dirUnlinkHierarchy(dn) < 0) {
fail = 1;
break;
}
errno = 0;
}
/* in case readdir or unlink_recursive failed */
if (fail || errno < 0) {
int save = errno;
closedir(dir);
errno = save;
return -1;
}
/* close directory handle */
if (closedir(dir) < 0) {
return -1;
}
/* delete target directory */
return rmdir(path);
}
int
dirSetHierarchyPermissions(const char *path,
int uid, int gid, int dirMode, int fileMode)
{
struct stat st;
if (lstat(path, &st)) {
return -1;
}
/* ignore symlinks */
if (S_ISLNK(st.st_mode)) {
return 0;
}
/* directories and files get different permissions */
if (chown(path, uid, gid) ||
chmod(path, S_ISDIR(st.st_mode) ? dirMode : fileMode)) {
return -1;
}
/* recurse over directory components */
if (S_ISDIR(st.st_mode)) {
DIR *dir = opendir(path);
if (dir == NULL) {
return -1;
}
errno = 0;
const struct dirent *de;
while (errno == 0 && (de = readdir(dir)) != NULL) {
if (!strcmp(de->d_name, "..") || !strcmp(de->d_name, ".")) {
continue;
}
char dn[PATH_MAX];
snprintf(dn, sizeof(dn), "%s/%s", path, de->d_name);
if (!dirSetHierarchyPermissions(dn, uid, gid, dirMode, fileMode)) {
errno = 0;
} else if (errno == 0) {
errno = -1;
}
}
if (errno != 0) {
int save = errno;
closedir(dir);
errno = save;
return -1;
}
if (closedir(dir)) {
return -1;
}
}
return 0;
}
