1 /* $NetBSD: file.h,v 1.8 2025/01/26 16:25:40 christos Exp $ */ 2 3 /* 4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC") 5 * 6 * SPDX-License-Identifier: MPL-2.0 7 * 8 * This Source Code Form is subject to the terms of the Mozilla Public 9 * License, v. 2.0. If a copy of the MPL was not distributed with this 10 * file, you can obtain one at https://mozilla.org/MPL/2.0/. 11 * 12 * See the COPYRIGHT file distributed with this work for additional 13 * information regarding copyright ownership. 14 */ 15 16 #pragma once 17 18 /*! \file isc/file.h */ 19 20 #include <stdbool.h> 21 #include <stdio.h> 22 #include <sys/stat.h> 23 24 #include <isc/lang.h> 25 #include <isc/types.h> 26 27 ISC_LANG_BEGINDECLS 28 29 isc_result_t 30 isc_file_settime(const char *file, isc_time_t *time); 31 32 isc_result_t 33 isc_file_mode(const char *file, mode_t *modep); 34 35 isc_result_t 36 isc_file_getmodtime(const char *file, isc_time_t *time); 37 /*!< 38 * \brief Get the time of last modification of a file. 39 * 40 * Notes: 41 *\li The time that is set is relative to the (OS-specific) epoch, as are 42 * all isc_time_t structures. 43 * 44 * Requires: 45 *\li file != NULL. 46 *\li time != NULL. 47 * 48 * Ensures: 49 *\li If the file could not be accessed, 'time' is unchanged. 50 * 51 * Returns: 52 *\li #ISC_R_SUCCESS 53 * Success. 54 *\li #ISC_R_NOTFOUND 55 * No such file exists. 56 *\li #ISC_R_INVALIDFILE 57 * The path specified was not usable by the operating system. 58 *\li #ISC_R_NOPERM 59 * The file's metainformation could not be retrieved because 60 * permission was denied to some part of the file's path. 61 *\li #ISC_R_IOERROR 62 * Hardware error interacting with the filesystem. 63 *\li #ISC_R_UNEXPECTED 64 * Something totally unexpected happened. 65 * 66 */ 67 68 isc_result_t 69 isc_file_mktemplate(const char *path, char *buf, size_t buflen); 70 /*!< 71 * \brief Generate a template string suitable for use with 72 * isc_file_openunique(). 73 * 74 * Notes: 75 *\li This function is intended to make creating temporary files 76 * portable between different operating systems. 77 * 78 *\li The path is prepended to an implementation-defined string and 79 * placed into buf. The string has no path characters in it, 80 * and its maximum length is 14 characters plus a NUL. Thus 81 * buflen should be at least strlen(path) + 15 characters or 82 * an error will be returned. 83 * 84 * Requires: 85 *\li buf != NULL. 86 * 87 * Ensures: 88 *\li If result == #ISC_R_SUCCESS: 89 * buf contains a string suitable for use as the template argument 90 * to isc_file_openunique(). 91 * 92 *\li If result != #ISC_R_SUCCESS: 93 * buf is unchanged. 94 * 95 * Returns: 96 *\li #ISC_R_SUCCESS Success. 97 *\li #ISC_R_NOSPACE buflen indicates buf is too small for the catenation 98 * of the path with the internal template string. 99 */ 100 101 isc_result_t 102 isc_file_openunique(char *templet, FILE **fp); 103 isc_result_t 104 isc_file_openuniqueprivate(char *templet, FILE **fp); 105 isc_result_t 106 isc_file_openuniquemode(char *templet, int mode, FILE **fp); 107 /*!< 108 * \brief Create and open a file with a unique name based on 'templet'. 109 * 110 * Notes: 111 *\li 'template' is a reserved work in C++. If you want to complain 112 * about the spelling of 'templet', first look it up in the 113 * Merriam-Webster English dictionary. (http://www.m-w.com/) 114 * 115 *\li This function works by using the template to generate file names. 116 * The template must be a writable string, as it is modified in place. 117 * Trailing X characters in the file name (full file name on Unix, 118 * basename on Win32 -- eg, tmp-XXXXXX vs XXXXXX.tmp, respectively) 119 * are replaced with ASCII characters until a non-existent filename 120 * is found. If the template does not include pathname information, 121 * the files in the working directory of the program are searched. 122 * 123 *\li isc_file_mktemplate is a good, portable way to get a template. 124 * 125 * Requires: 126 *\li 'fp' is non-NULL and '*fp' is NULL. 127 * 128 *\li 'template' is non-NULL, and of a form suitable for use by 129 * the system as described above. 130 * 131 * Ensures: 132 *\li If result is #ISC_R_SUCCESS: 133 * *fp points to an stream opening in stdio's "w+" mode. 134 * 135 *\li If result is not #ISC_R_SUCCESS: 136 * *fp is NULL. 137 * 138 * No file is open. Even if one was created (but unable 139 * to be reopened as a stdio FILE pointer) then it has been 140 * removed. 141 * 142 *\li This function does *not* ensure that the template string has not been 143 * modified, even if the operation was unsuccessful. 144 * 145 * Returns: 146 *\li #ISC_R_SUCCESS 147 * Success. 148 *\li #ISC_R_EXISTS 149 * No file with a unique name could be created based on the 150 * template. 151 *\li #ISC_R_INVALIDFILE 152 * The path specified was not usable by the operating system. 153 *\li #ISC_R_NOPERM 154 * The file could not be created because permission was denied 155 * to some part of the file's path. 156 *\li #ISC_R_IOERROR 157 * Hardware error interacting with the filesystem. 158 *\li #ISC_R_UNEXPECTED 159 * Something totally unexpected happened. 160 */ 161 162 isc_result_t 163 isc_file_remove(const char *filename); 164 /*!< 165 * \brief Remove the file named by 'filename'. 166 */ 167 168 isc_result_t 169 isc_file_rename(const char *oldname, const char *newname); 170 /*!< 171 * \brief Rename the file 'oldname' to 'newname'. 172 */ 173 174 bool 175 isc_file_exists(const char *pathname); 176 /*!< 177 * \brief Return #true if the calling process can tell that the given file 178 * exists. Will not return true if the calling process has insufficient 179 * privileges to search the entire path. 180 */ 181 182 bool 183 isc_file_isabsolute(const char *filename); 184 /*!< 185 * \brief Return #true if the given file name is absolute. 186 */ 187 188 isc_result_t 189 isc_file_isplainfile(const char *name); 190 191 isc_result_t 192 isc_file_isplainfilefd(int fd); 193 /*!< 194 * \brief Check that the file is a plain file 195 * 196 * Returns: 197 *\li #ISC_R_SUCCESS 198 * Success. The file is a plain file. 199 *\li #ISC_R_INVALIDFILE 200 * The path specified was not usable by the operating system. 201 *\li #ISC_R_FILENOTFOUND 202 * The file does not exist. This return code comes from 203 * errno=ENOENT when stat returns -1. This code is mentioned 204 * here, because in logconf.c, it is the one rcode that is 205 * permitted in addition to ISC_R_SUCCESS. This is done since 206 * the next call in logconf.c is to isc_stdio_open(), which 207 * will create the file if it can. 208 *\li other ISC_R_* errors translated from errno 209 * These occur when stat returns -1 and an errno. 210 */ 211 212 isc_result_t 213 isc_file_isdirectory(const char *name); 214 /*!< 215 * \brief Check that 'name' exists and is a directory. 216 * 217 * Returns: 218 *\li #ISC_R_SUCCESS 219 * Success, file is a directory. 220 *\li #ISC_R_INVALIDFILE 221 * File is not a directory. 222 *\li #ISC_R_FILENOTFOUND 223 * File does not exist. 224 *\li other ISC_R_* errors translated from errno 225 * These occur when stat returns -1 and an errno. 226 */ 227 228 bool 229 isc_file_iscurrentdir(const char *filename); 230 /*!< 231 * \brief Return #true if the given file name is the current directory ("."). 232 */ 233 234 bool 235 isc_file_ischdiridempotent(const char *filename); 236 /*%< 237 * Return #true if calling chdir(filename) multiple times will give 238 * the same result as calling it once. 239 */ 240 241 const char * 242 isc_file_basename(const char *filename); 243 /*%< 244 * Return the final component of the path in the file name. 245 */ 246 247 isc_result_t 248 isc_file_progname(const char *filename, char *buf, size_t buflen); 249 /*!< 250 * \brief Given an operating system specific file name "filename" 251 * referring to a program, return the canonical program name. 252 * 253 * Any directory prefix or executable file name extension (if 254 * used on the OS in case) is stripped. On systems where program 255 * names are case insensitive, the name is canonicalized to all 256 * lower case. The name is written to 'buf', an array of 'buflen' 257 * chars, and null terminated. 258 * 259 * Returns: 260 *\li #ISC_R_SUCCESS 261 *\li #ISC_R_NOSPACE The name did not fit in 'buf'. 262 */ 263 264 isc_result_t 265 isc_file_template(const char *path, const char *templet, char *buf, 266 size_t buflen); 267 /*%< 268 * Create an OS specific template using 'path' to define the directory 269 * 'templet' to describe the filename and store the result in 'buf' 270 * such that path can be renamed to buf atomically. 271 */ 272 273 isc_result_t 274 isc_file_renameunique(const char *file, char *templet); 275 /*%< 276 * Rename 'file' using 'templet' as a template for the new file name. 277 */ 278 279 isc_result_t 280 isc_file_absolutepath(const char *filename, char *path, size_t pathlen); 281 /*%< 282 * Given a file name, return the fully qualified path to the file. 283 */ 284 285 /* 286 * XXX We should also have a isc_file_writeeopen() function 287 * for safely open a file in a publicly writable directory 288 * (see write_open() in BIND 8's ns_config.c). 289 */ 290 291 isc_result_t 292 isc_file_truncate(const char *filename, off_t size); 293 /*%< 294 * Truncate/extend the file specified to 'size' bytes. 295 */ 296 297 isc_result_t 298 isc_file_safecreate(const char *filename, FILE **fp); 299 /*%< 300 * Open 'filename' for writing, truncating if necessary. Ensure that 301 * if it existed it was a normal file. If creating the file, ensure 302 * that only the owner can read/write it. 303 */ 304 305 isc_result_t 306 isc_file_splitpath(isc_mem_t *mctx, const char *path, char **dirname, 307 char const **basename); 308 /*%< 309 * Split a path into dirname and basename. If 'path' contains no slash, 310 * then '*dirname' is set to ".". 311 * 312 * Allocates memory for '*dirname', which can be freed with isc_mem_free(). 313 * 314 * Returns: 315 * - ISC_R_SUCCESS on success 316 * - ISC_R_INVALIDFILE if 'path' is empty or ends with '/' 317 * - ISC_R_NOMEMORY if unable to allocate memory 318 */ 319 320 isc_result_t 321 isc_file_getsize(const char *file, off_t *size); 322 /*%< 323 * Return the size of the file (stored in the parameter pointed 324 * to by 'size') in bytes. 325 * 326 * Returns: 327 * - ISC_R_SUCCESS on success 328 */ 329 330 isc_result_t 331 isc_file_getsizefd(int fd, off_t *size); 332 /*%< 333 * Return the size of the file (stored in the parameter pointed 334 * to by 'size') in bytes. 335 * 336 * Returns: 337 * - ISC_R_SUCCESS on success 338 */ 339 340 isc_result_t 341 isc_file_sanitize(const char *dir, const char *base, const char *ext, 342 char *path, size_t length); 343 /*%< 344 * Generate a sanitized filename, such as for MKEYS or NZF files. 345 * 346 * Historically, MKEYS and NZF files used SHA256 hashes of the view 347 * name for the filename; this was to deal with the possibility of 348 * forbidden characters such as "/" being in a view name, and to 349 * avoid problems with case-insensitive file systems. 350 * 351 * Given a basename 'base' and an extension 'ext', this function checks 352 * for the existence of file using the old-style name format in directory 353 * 'dir'. If found, it returns the path to that file. If there is no 354 * file already in place, a new pathname is generated; if the basename 355 * contains any excluded characters, then a truncated SHA256 hash is 356 * used, otherwise the basename is used. The path name is copied 357 * into 'path', which must point to a buffer of at least 'length' 358 * bytes. 359 * 360 * Requires: 361 * - base != NULL 362 * - path != NULL 363 * 364 * Returns: 365 * - ISC_R_SUCCESS on success 366 * - ISC_R_NOSPACE if the resulting path would be longer than 'length' 367 */ 368 369 bool 370 isc_file_isdirwritable(const char *path); 371 /*%< 372 * Return true if the path is a directory and is writable 373 */ 374 375 ISC_LANG_ENDDECLS 376
Indexes created Mon Mar 02 05:31:46 UTC 2026