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Diffstat (limited to 'otautil/DirUtil.cpp')
| -rw-r--r-- | otautil/DirUtil.cpp | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/otautil/DirUtil.cpp b/otautil/DirUtil.cpp new file mode 100644 index 000000000..e08e360c0 --- /dev/null +++ b/otautil/DirUtil.cpp @@ -0,0 +1,218 @@ +/* + * 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 "DirUtil.h" + +#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 <string> + +#include <selinux/label.h> +#include <selinux/selinux.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. + std::string cpath = path; + if (stripFileName) { + // Strip everything after the last slash. + size_t pos = cpath.rfind('/'); + if (pos == std::string::npos) { + errno = ENOENT; + return -1; + } + cpath.resize(pos + 1); + } else { + // Make sure that the path ends in a slash. + cpath.push_back('/'); + } + + /* See if it already exists. + */ + ds = getPathDirStatus(cpath.c_str()); + 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. + */ + const char *path_start = &cpath[0]; + char *p = &cpath[0]; + 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(path_start); + if (ds == DILLEGAL) { + /* Could happen if some other process/thread is + * messing with the filesystem. + */ + return -1; + } else if (ds == DMISSING) { + int err; + + char *secontext = NULL; + + if (sehnd) { + selabel_lookup(sehnd, &secontext, path_start, mode); + setfscreatecon(secontext); + } + + err = mkdir(path_start, mode); + + if (secontext) { + freecon(secontext); + setfscreatecon(NULL); + } + + if (err != 0) { + return -1; + } + if (timestamp != NULL && utime(path_start, timestamp)) { + return -1; + } + } + // else, this directory already exists. + + // Repair the path and continue. + *p = '/'; + } + 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); +} |