/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#ifndef ISC_FILE_H
#define ISC_FILE_H 1
/*! \file isc/file.h */
#include <stdbool.h>
#include <stdio.h>
#include <isc/lang.h>
#include <isc/stat.h>
#include <isc/types.h>
ISC_LANG_BEGINDECLS
isc_result_t
isc_file_settime(const char *file, isc_time_t *time);
isc_result_t
isc_file_mode(const char *file, mode_t *modep);
isc_result_t
isc_file_getmodtime(const char *file, isc_time_t *time);
/*!<
* \brief Get the time of last modification of a file.
*
* Notes:
*\li The time that is set is relative to the (OS-specific) epoch, as are
* all isc_time_t structures.
*
* Requires:
*\li file != NULL.
*\li time != NULL.
*
* Ensures:
*\li If the file could not be accessed, 'time' is unchanged.
*
* Returns:
*\li #ISC_R_SUCCESS
* Success.
*\li #ISC_R_NOTFOUND
* No such file exists.
*\li #ISC_R_INVALIDFILE
* The path specified was not usable by the operating system.
*\li #ISC_R_NOPERM
* The file's metainformation could not be retrieved because
* permission was denied to some part of the file's path.
*\li #ISC_R_IOERROR
* Hardware error interacting with the filesystem.
*\li #ISC_R_UNEXPECTED
* Something totally unexpected happened.
*
*/
isc_result_t
isc_file_mktemplate(const char *path, char *buf, size_t buflen);
/*!<
* \brief Generate a template string suitable for use with isc_file_openunique().
*
* Notes:
*\li This function is intended to make creating temporary files
* portable between different operating systems.
*
*\li The path is prepended to an implementation-defined string and
* placed into buf. The string has no path characters in it,
* and its maximum length is 14 characters plus a NUL. Thus
* buflen should be at least strlen(path) + 15 characters or
* an error will be returned.
*
* Requires:
*\li buf != NULL.
*
* Ensures:
*\li If result == #ISC_R_SUCCESS:
* buf contains a string suitable for use as the template argument
* to isc_file_openunique().
*
*\li If result != #ISC_R_SUCCESS:
* buf is unchanged.
*
* Returns:
*\li #ISC_R_SUCCESS Success.
*\li #ISC_R_NOSPACE buflen indicates buf is too small for the catenation
* of the path with the internal template string.
*/
isc_result_t
isc_file_openunique(char *templet, FILE **fp);
isc_result_t
isc_file_openuniqueprivate(char *templet, FILE **fp);
isc_result_t
isc_file_openuniquemode(char *templet, int mode, FILE **fp);
isc_result_t
isc_file_bopenunique(char *templet, FILE **fp);
isc_result_t
isc_file_bopenuniqueprivate(char *templet, FILE **fp);
isc_result_t
isc_file_bopenuniquemode(char *templet, int mode, FILE **fp);
/*!<
* \brief Create and open a file with a unique name based on 'templet'.
* isc_file_bopen*() open the file in binary mode in Windows.
* isc_file_open*() open the file in text mode in Windows.
*
* Notes:
*\li 'template' is a reserved work in C++. If you want to complain
* about the spelling of 'templet', first look it up in the
* Merriam-Webster English dictionary. (http://www.m-w.com/)
*
*\li This function works by using the template to generate file names.
* The template must be a writable string, as it is modified in place.
* Trailing X characters in the file name (full file name on Unix,
* basename on Win32 -- eg, tmp-XXXXXX vs XXXXXX.tmp, respectively)
* are replaced with ASCII characters until a non-existent filename
* is found. If the template does not include pathname information,
* the files in the working directory of the program are searched.
*
*\li isc_file_mktemplate is a good, portable way to get a template.
*
* Requires:
*\li 'fp' is non-NULL and '*fp' is NULL.
*
*\li 'template' is non-NULL, and of a form suitable for use by
* the system as described above.
*
* Ensures:
*\li If result is #ISC_R_SUCCESS:
* *fp points to an stream opening in stdio's "w+" mode.
*
*\li If result is not #ISC_R_SUCCESS:
* *fp is NULL.
*
* No file is open. Even if one was created (but unable
* to be reopened as a stdio FILE pointer) then it has been
* removed.
*
*\li This function does *not* ensure that the template string has not been
* modified, even if the operation was unsuccessful.
*
* Returns:
*\li #ISC_R_SUCCESS
* Success.
*\li #ISC_R_EXISTS
* No file with a unique name could be created based on the
* template.
*\li #ISC_R_INVALIDFILE
* The path specified was not usable by the operating system.
*\li #ISC_R_NOPERM
* The file could not be created because permission was denied
* to some part of the file's path.
*\li #ISC_R_IOERROR
* Hardware error interacting with the filesystem.
*\li #ISC_R_UNEXPECTED
* Something totally unexpected happened.
*/
isc_result_t
isc_file_remove(const char *filename);
/*!<
* \brief Remove the file named by 'filename'.
*/
isc_result_t
isc_file_rename(const char *oldname, const char *newname);
/*!<
* \brief Rename the file 'oldname' to 'newname'.
*/
bool
isc_file_exists(const char *pathname);
/*!<
* \brief Return #true if the calling process can tell that the given file exists.
* Will not return true if the calling process has insufficient privileges
* to search the entire path.
*/
bool
isc_file_isabsolute(const char *filename);
/*!<
* \brief Return #true if the given file name is absolute.
*/
isc_result_t
isc_file_isplainfile(const char *name);
isc_result_t
isc_file_isplainfilefd(int fd);
/*!<
* \brief Check that the file is a plain file
*
* Returns:
*\li #ISC_R_SUCCESS
* Success. The file is a plain file.
*\li #ISC_R_INVALIDFILE
* The path specified was not usable by the operating system.
*\li #ISC_R_FILENOTFOUND
* The file does not exist. This return code comes from
* errno=ENOENT when stat returns -1. This code is mentioned
* here, because in logconf.c, it is the one rcode that is
* permitted in addition to ISC_R_SUCCESS. This is done since
* the next call in logconf.c is to isc_stdio_open(), which
* will create the file if it can.
*\li other ISC_R_* errors translated from errno
* These occur when stat returns -1 and an errno.
*/
isc_result_t
isc_file_isdirectory(const char *name);
/*!<
* \brief Check that 'name' exists and is a directory.
*
* Returns:
*\li #ISC_R_SUCCESS
* Success, file is a directory.
*\li #ISC_R_INVALIDFILE
* File is not a directory.
*\li #ISC_R_FILENOTFOUND
* File does not exist.
*\li other ISC_R_* errors translated from errno
* These occur when stat returns -1 and an errno.
*/
bool
isc_file_iscurrentdir(const char *filename);
/*!<
* \brief Return #true if the given file name is the current directory (".").
*/
bool
isc_file_ischdiridempotent(const char *filename);
/*%<
* Return #true if calling chdir(filename) multiple times will give
* the same result as calling it once.
*/
const char *
isc_file_basename(const char *filename);
/*%<
* Return the final component of the path in the file name.
*/
isc_result_t
isc_file_progname(const char *filename, char *buf, size_t buflen);
/*!<
* \brief Given an operating system specific file name "filename"
* referring to a program, return the canonical program name.
*
* Any directory prefix or executable file name extension (if
* used on the OS in case) is stripped. On systems where program
* names are case insensitive, the name is canonicalized to all
* lower case. The name is written to 'buf', an array of 'buflen'
* chars, and null terminated.
*
* Returns:
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOSPACE The name did not fit in 'buf'.
*/
isc_result_t
isc_file_template(const char *path, const char *templet, char *buf,
size_t buflen);
/*%<
* Create an OS specific template using 'path' to define the directory
* 'templet' to describe the filename and store the result in 'buf'
* such that path can be renamed to buf atomically.
*/
isc_result_t
isc_file_renameunique(const char *file, char *templet);
/*%<
* Rename 'file' using 'templet' as a template for the new file name.
*/
isc_result_t
isc_file_absolutepath(const char *filename, char *path, size_t pathlen);
/*%<
* Given a file name, return the fully qualified path to the file.
*/
/*
* XXX We should also have a isc_file_writeeopen() function
* for safely open a file in a publicly writable directory
* (see write_open() in BIND 8's ns_config.c).
*/
isc_result_t
isc_file_truncate(const char *filename, isc_offset_t size);
/*%<
* Truncate/extend the file specified to 'size' bytes.
*/
isc_result_t
isc_file_safecreate(const char *filename, FILE **fp);
/*%<
* Open 'filename' for writing, truncating if necessary. Ensure that
* if it existed it was a normal file. If creating the file, ensure
* that only the owner can read/write it.
*/
isc_result_t
isc_file_splitpath(isc_mem_t *mctx, const char *path,
char **dirname, char const **basename);
/*%<
* Split a path into dirname and basename. If 'path' contains no slash
* (or, on windows, backslash), then '*dirname' is set to ".".
*
* Allocates memory for '*dirname', which can be freed with isc_mem_free().
*
* Returns:
* - ISC_R_SUCCESS on success
* - ISC_R_INVALIDFILE if 'path' is empty or ends with '/'
* - ISC_R_NOMEMORY if unable to allocate memory
*/
isc_result_t
isc_file_getsize(const char *file, off_t *size);
/*%<
* Return the size of the file (stored in the parameter pointed
* to by 'size') in bytes.
*
* Returns:
* - ISC_R_SUCCESS on success
*/
isc_result_t
isc_file_getsizefd(int fd, off_t *size);
/*%<
* Return the size of the file (stored in the parameter pointed
* to by 'size') in bytes.
*
* Returns:
* - ISC_R_SUCCESS on success
*/
void *
isc_file_mmap(void *addr, size_t len, int prot,
int flags, int fd, off_t offset);
/*%<
* Portable front-end to mmap(). If mmap() is not defined on this
* platform, then we simulate it by calling malloc() and read().
* (In this event, the addr, prot, and flags parameters are ignored).
*/
int
isc_file_munmap(void *addr, size_t len);
/*%<
* Portable front-end to munmap(). If munmap() is not defined on
* this platform, then we simply free the memory.
*/
isc_result_t
isc_file_sanitize(const char *dir, const char *base, const char *ext,
char *path, size_t length);
/*%<
* Generate a sanitized filename, such as for MKEYS or NZF files.
*
* Historically, MKEYS and NZF files used SHA256 hashes of the view
* name for the filename; this was to deal with the possibility of
* forbidden characters such as "/" being in a view name, and to
* avoid problems with case-insensitive file systems.
*
* Given a basename 'base' and an extension 'ext', this function checks
* for the existence of file using the old-style name format in directory
* 'dir'. If found, it returns the path to that file. If there is no
* file already in place, a new pathname is generated; if the basename
* contains any excluded characters, then a truncated SHA256 hash is
* used, otherwise the basename is used. The path name is copied
* into 'path', which must point to a buffer of at least 'length'
* bytes.
*
* Requires:
* - base != NULL
* - path != NULL
*
* Returns:
* - ISC_R_SUCCESS on success
* - ISC_R_NOSPACE if the resulting path would be longer than 'length'
*/
bool
isc_file_isdirwritable(const char *path);
/*%<
* Return true if the path is a directory and is writable
*/
ISC_LANG_ENDDECLS
#endif /* ISC_FILE_H */
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