filesystem.h

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/* Copyright (C) 2022 Wildfire Games.
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 * permit persons to whom the Software is furnished to do so, subject to
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 * The above copyright notice and this permission notice shall be included
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/*
 * wchar_t versions of POSIX filesystem functions
 */
 
#ifndef INCLUDED_SYSDEP_FILESYSTEM
#define INCLUDED_SYSDEP_FILESYSTEM
 
#include "lib/os_path.h"
#include "lib/posix/posix_filesystem.h" // mode_t
 
 
//
// dirent.h
//
 
struct WDIR;
 
struct wdirent
{
    // note: SUSv3 describes this as a "char array" but of unspecified size.
    // we declare as a pointer to avoid having to copy the string.
    wchar_t* d_name;
};
 
extern WDIR* wopendir(const OsPath& path);
 
extern wdirent* wreaddir(WDIR*);
 
// return status for the file returned by the last successful
// wreaddir call from the given directory stream.
// currently sets st_size, st_mode, and st_mtime; the rest are zeroed.
// non-portable, but considerably faster than stat(). used by dir_ForEachSortedEntry.
extern int wreaddir_stat_np(WDIR*, struct stat*);
 
extern int wclosedir(WDIR*);
 
 
//
// fcntl.h
//
 
// transfer directly to/from user's buffer.
// treated as a request to enable aio.
#ifndef O_DIRECT    // i.e. Windows or OS X
#define O_DIRECT 0x10000000 // (value does not conflict with any current Win32 _O_* flags.)
#endif
 
// Win32 _wsopen_s does not open files in a manner compatible with waio.
// if its aio_read/aio_write are to be used, waio_open must (also) be called.
// calling both is possible but wasteful and unsafe, since it prevents
// file sharing restrictions, which are the only way to prevent
// exposing previous data as a side effect of waio_Preallocate.
// applications shouldn't mix aio and synchronous I/O anyway, so we
// want wopen to call either waio_open or _wsopen_s.
// since waio requires callers to respect the FILE_FLAG_NO_BUFFERING
// restrictions (sector alignment), and IRIX/BSD/Linux O_DIRECT imposes
// similar semantics, we treat that flag as a request to enable aio.
extern int wopen(const OsPath& pathname, int oflag);
extern int wopen(const OsPath& pathname, int oflag, mode_t mode);
extern int wclose(int fd);
 
 
//
// unistd.h
//
 
// waio requires offsets and sizes to be multiples of the sector size.
// to allow arbitrarily sized files, we truncate them after I/O.
// however, ftruncate cannot be used since it is also subject to the
// sector-alignment requirement. instead, the file must be closed and
// this function called.
int wtruncate(const OsPath& pathname, off_t length);
 
int wunlink(const OsPath& pathname);
 
int wrmdir(const OsPath& path);
 
 
//
// stdlib.h
//
 
OsPath wrealpath(const OsPath& pathname);
 
 
//
// sys/stat.h
//
 
int wstat(const OsPath& pathname, struct stat* buf);
 
int wmkdir(const OsPath& path, mode_t mode);
 
#endif  // #ifndef INCLUDED_SYSDEP_FILESYSTEM