1/* $NetBSD: remove.c,v 1.3 2021/04/10 19:49:59 nia Exp $ */ 2 3/*- 4 * Copyright (c) 2008 Joerg Sonnenberger <joerg@NetBSD.org>. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 22 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 28 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32#if HAVE_CONFIG_H 33#include "config.h" 34#endif 35 36#include <nbcompat.h> 37 38#if HAVE_SYS_CDEFS_H 39#include <sys/cdefs.h> 40#endif 41 42__RCSID("$NetBSD: remove.c,v 1.3 2021/04/10 19:49:59 nia Exp $"); 43 44#if HAVE_DIRENT_H 45#include <dirent.h> 46#endif 47#if HAVE_ERR_H 48#include <err.h> 49#endif 50#include <errno.h> 51#if HAVE_FCNTL_H 52#include <fcntl.h> 53#endif 54#include <limits.h> 55#include <stdio.h> 56#include <stdlib.h> 57#include <string.h> 58#include <unistd.h> 59 60#include "lib.h" 61 62static int 63safe_fchdir(int cwd) 64{ 65 int tmp_errno, rv; 66 67 tmp_errno = errno; 68 rv = fchdir(cwd); 69 errno = tmp_errno; 70 71 return rv; 72} 73 74static int 75long_remove(const char **path_ptr, int missing_ok, int *did_chdir) 76{ 77 char tmp_path[PATH_MAX + 1]; 78 const char *path; 79 size_t i, len; 80 int rv; 81 82 path = *path_ptr; 83 len = strlen(path); 84 *did_chdir = 0; 85 86 while (len >= PATH_MAX) { 87 for (i = PATH_MAX - 1; i > 0; --i) { 88 if (path[i] == '/') 89 break; 90 } 91 if (i == 0) { 92 errno = ENAMETOOLONG; 93 return -1; /* Assumes PATH_MAX > NAME_MAX */ 94 } 95 memcpy(tmp_path, path, i); 96 tmp_path[i] = '\0'; 97 if (chdir(tmp_path)) 98 return -1; 99 *did_chdir = 1; 100 path += i + 1; 101 len -= i + 1; 102 } 103 104 if (remove(path) == 0 || (errno == ENOENT && missing_ok)) 105 rv = 0; 106 else 107 rv = -1; 108 109 *path_ptr = path; 110 111 return rv; 112} 113 114static int 115recursive_remove_internal(const char *path, int missing_ok, int cwd) 116{ 117 DIR *dir; 118 struct dirent *de; 119 const char *sub_path; 120 char *subdir; 121 int did_chdir, rv; 122 123 /* 124 * If the argument is longer than PATH_MAX, long_remove 125 * will try to shorten it using chdir. So before returning, 126 * make sure to fchdir back to the original cwd. 127 */ 128 sub_path = path; 129 if (long_remove(&sub_path, missing_ok, &did_chdir) == 0) 130 rv = 0; 131 else if (errno != ENOTEMPTY) /* Other errors are terminal. */ 132 rv = -1; 133 else 134 rv = 1; 135 136 if (rv != 1) { 137 if (did_chdir && safe_fchdir(cwd) == -1 && rv == 0) 138 rv = -1; 139 return rv; 140 } 141 142 if ((dir = opendir(sub_path)) == NULL) { 143 if (errno == EMFILE) 144 warn("opendir failed"); 145 return -1; 146 } 147 148 if (did_chdir && fchdir(cwd) == -1) 149 return -1; 150 151 rv = 0; 152 153 while ((de = readdir(dir)) != NULL) { 154 if (strcmp(de->d_name, ".") == 0) 155 continue; 156 if (strcmp(de->d_name, "..") == 0) 157 continue; 158 subdir = xasprintf("%s/%s", path, de->d_name); 159 rv = recursive_remove_internal(subdir, 1, cwd); 160 free(subdir); 161 } 162 163 closedir(dir); 164 165 safe_fchdir(cwd); 166 167 rv |= long_remove(&path, missing_ok, &did_chdir); 168 169 if (did_chdir && safe_fchdir(cwd) == -1 && rv == 0) 170 rv = -1; 171 172 return rv; 173} 174 175int 176recursive_remove(const char *path, int missing_ok) 177{ 178 int orig_cwd, rv; 179 180 /* First try the easy case of regular file or empty directory. */ 181 if (remove(path) == 0 || (errno == ENOENT && missing_ok)) 182 return 0; 183 184 /* 185 * If the path is too long, long_remove will use chdir to shorten it, 186 * so remember the current directory first. 187 */ 188 if ((orig_cwd = open(".", O_RDONLY)) == -1) 189 return -1; 190 191 rv = recursive_remove_internal(path, missing_ok, orig_cwd); 192 193 close(orig_cwd); 194 return rv; 195} 196