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909 lines
26 KiB
C++
909 lines
26 KiB
C++
//
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// open.cpp
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//
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// Copyright (c) Microsoft Corporation. All rights reserved.
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//
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// Defines _open() and its friends, who are used to open or create files.
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//
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// These functions are used to open a file.
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//
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// oflag: The primary file open flags are passed via this parameter. It may
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// have a combination of the following flags:
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// * _O_APPEND: Reposition file ptr to end before every write
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// * _O_BINARY: Open in binary mode
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// * _O_CREAT: Create a new file* no effect if file already exists
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// * _O_EXCL: Return error if file exists, only use with O_CREAT
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// * _O_RDONLY: Open for reading only
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// * _O_RDWR: Open for reading and writing
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// * _O_TEXT: Open in text mode
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// * _O_TRUNC: Open and truncate to 0 length (must have write permission)
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// * _O_WRONLY: Open for writing only
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// * _O_NOINHERIT: Handle will not be inherited by child processes.
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// Exactly one of _O_RDONLY, _O_WRONLY, and _O_RDWR must be present.
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//
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// shflag: Specifies the sharing options with which the file is to be opened.
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// This parameter is only supported by the sharing-enabled open
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// functions (_tsopen, _tsopen_s, etc.). The following flags are
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// supported:
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// * _SH_COMPAT: Set compatability mode
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// * _SH_DENYRW: Deny read and write access to the file
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// * _SH_DENYWR: Deny write access to the file
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// * _SH_DENYRD: Deny read access to the file
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// * _SH_DENYNO: Permit read and write access
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//
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// pmode: The pmode argument is only required when _O_CREAT is specified. Its
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// flags are as follows:
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// * _S_IWRITE:
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// * _S_IREAD:
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// These flags may be combined (_S_IWRITE | _S_IREAD) to enable both
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// reading and writing. The current file permission mask is applied to
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// pmode before setting the permission (see umask).
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//
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// Functions that return an errno_t return 0 on success and an error code on
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// failure. Functions that return an int return the file handle on success, and
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// return -1 and set errno on failure.
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//
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#include <corecrt_internal_lowio.h>
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#include <stdarg.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/stat.h>
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namespace
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{
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DWORD const GENERIC_READ_WRITE = (GENERIC_READ | GENERIC_WRITE);
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struct file_options
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{
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// These are the flags that are used for the osflag of the CRT file
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// object that is created.
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char crt_flags;
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// These are the flags that are eventually passed to CreateFile to tell
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// the Operating System how to create the file:
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DWORD access;
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DWORD create;
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DWORD share;
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DWORD attributes;
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DWORD flags;
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};
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}
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#define UTF16LE_BOM 0xFEFF // UTF16 Little Endian Byte Order Mark
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#define UTF16BE_BOM 0xFFFE // UTF16 Big Endian Byte Order Mark
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#define BOM_MASK 0xFFFF // Mask for testing Byte Order Mark
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#define UTF8_BOM 0xBFBBEF // UTF8 Byte Order Mark
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#define UTF16_BOMLEN 2 // No of Bytes in a UTF16 BOM
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#define UTF8_BOMLEN 3 // No of Bytes in a UTF8 BOM
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template <typename Character>
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static int __cdecl common_open(
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_In_z_ Character const* const path,
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int const oflag,
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int const pmode
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) throw()
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{
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typedef __crt_char_traits<Character> traits;
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_VALIDATE_RETURN(path != nullptr, EINVAL, -1);
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int fh = -1;
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int unlock_flag = 0;
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errno_t error_code = 0;
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__try
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{
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error_code = traits::tsopen_nolock(&unlock_flag, &fh, path, oflag, _SH_DENYNO, pmode, 0);
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}
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__finally
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{
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if (unlock_flag)
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{
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if (error_code)
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{
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_osfile(fh) &= ~FOPEN;
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}
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__acrt_lowio_unlock_fh(fh);
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}
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}
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__endtry
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if (error_code != 0)
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{
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errno = error_code;
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return -1;
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}
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return fh;
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}
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extern "C" int _open(char const* const path, int const oflag, ...)
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{
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va_list arglist;
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va_start(arglist, oflag);
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int const pmode = va_arg(arglist, int);
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va_end(arglist);
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return common_open(path, oflag, pmode);
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}
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extern "C" int _wopen(wchar_t const* const path, int const oflag, ...)
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{
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va_list arglist;
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va_start(arglist, oflag);
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int const pmode = va_arg(arglist, int);
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va_end(arglist);
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return common_open(path, oflag, pmode);
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}
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template <typename Character>
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static errno_t __cdecl common_sopen_dispatch(
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_In_z_ Character const* const path,
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int const oflag,
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int const shflag,
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int const pmode,
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int* const pfh,
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int const secure
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) throw()
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{
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typedef __crt_char_traits<Character> traits;
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_VALIDATE_RETURN_ERRCODE(pfh != nullptr, EINVAL);
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*pfh = -1;
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_VALIDATE_RETURN_ERRCODE(path != nullptr, EINVAL);
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if(secure)
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{
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_VALIDATE_RETURN_ERRCODE((pmode & (~(_S_IREAD | _S_IWRITE))) == 0, EINVAL);
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}
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int unlock_flag = 0;
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errno_t error_code = 0;
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__try
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{
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error_code = traits::tsopen_nolock(&unlock_flag, pfh, path, oflag, shflag, pmode, secure);
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}
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__finally
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{
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if (unlock_flag)
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{
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if (error_code)
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{
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_osfile(*pfh) &= ~FOPEN;
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}
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__acrt_lowio_unlock_fh(*pfh);
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}
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}
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__endtry
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if (error_code != 0)
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{
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*pfh = -1;
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}
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return error_code;
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}
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extern "C" errno_t __cdecl _sopen_dispatch(
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char const* const path,
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int const oflag,
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int const shflag,
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int const pmode,
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int* const pfh,
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int const secure
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)
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{
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return common_sopen_dispatch(path, oflag, shflag, pmode, pfh, secure);
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}
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extern "C" errno_t __cdecl _wsopen_dispatch(
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wchar_t const* const path,
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int const oflag,
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int const shflag,
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int const pmode,
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int* const pfh,
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int const secure
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)
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{
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return common_sopen_dispatch(path, oflag, shflag, pmode, pfh, secure);
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}
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static HANDLE __cdecl create_file(
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PCWSTR const path,
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SECURITY_ATTRIBUTES* const security_attributes,
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file_options const options
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) throw()
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{
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return CreateFileW(
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path,
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options.access,
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options.share,
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security_attributes,
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options.create,
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options.flags | options.attributes,
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nullptr);
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}
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static DWORD decode_access_flags(int const oflag) throw()
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{
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switch (oflag & (_O_RDONLY | _O_WRONLY | _O_RDWR))
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{
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case _O_RDONLY:
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return GENERIC_READ;
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case _O_WRONLY:
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// If the file is being opened in append mode, we give read access as
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// well because in append (a, not a+) mode, we need to read the BOM to
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// determine the encoding (ANSI, UTF-8, or UTF-16).
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if ((oflag & _O_APPEND) && (oflag & (_O_WTEXT | _O_U16TEXT | _O_U8TEXT)) != 0)
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return GENERIC_READ | GENERIC_WRITE;
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return GENERIC_WRITE;
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case _O_RDWR:
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return GENERIC_READ | GENERIC_WRITE;
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}
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// This is unreachable, but the compiler can't tell.
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_VALIDATE_RETURN(("Invalid open flag", 0), EINVAL, static_cast<DWORD>(-1));
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return 0;
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}
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static DWORD decode_open_create_flags(int const oflag) throw()
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{
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switch (oflag & (_O_CREAT | _O_EXCL | _O_TRUNC))
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{
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case 0:
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case _O_EXCL: // ignore EXCL w/o CREAT
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return OPEN_EXISTING;
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case _O_CREAT:
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return OPEN_ALWAYS;
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case _O_CREAT | _O_EXCL:
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case _O_CREAT | _O_TRUNC | _O_EXCL:
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return CREATE_NEW;
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case _O_TRUNC:
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case _O_TRUNC | _O_EXCL: // ignore EXCL w/o CREAT
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return TRUNCATE_EXISTING;
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case _O_CREAT | _O_TRUNC:
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return CREATE_ALWAYS;
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}
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// This is unreachable, but the compiler can't tell.
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_VALIDATE_RETURN(("Invalid open flag", 0), EINVAL, static_cast<DWORD>(-1));
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return 0;
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}
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static DWORD decode_sharing_flags(int const shflag, int const access) throw()
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{
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switch (shflag)
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{
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case _SH_DENYRW:
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return 0;
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case _SH_DENYWR:
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return FILE_SHARE_READ;
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case _SH_DENYRD:
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return FILE_SHARE_WRITE;
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case _SH_DENYNO:
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return FILE_SHARE_READ | FILE_SHARE_WRITE;
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case _SH_SECURE:
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if (access == GENERIC_READ)
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return FILE_SHARE_READ;
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else
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return 0;
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}
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_VALIDATE_RETURN(("Invalid sharing flag", 0), EINVAL, static_cast<DWORD>(-1));
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return 0;
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}
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static bool is_text_mode(int const oflag) throw()
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{
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if (oflag & _O_BINARY)
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return false;
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if (oflag & (_O_TEXT | _O_WTEXT | _O_U16TEXT | _O_U8TEXT))
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return true;
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// Finally, check the global default mode:
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int fmode;
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_ERRCHECK(_get_fmode(&fmode));
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if (fmode != _O_BINARY)
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return true;
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return false;
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}
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static file_options decode_options(int const oflag, int const shflag, int const pmode) throw()
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{
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file_options result;
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result.crt_flags = 0;
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result.access = decode_access_flags(oflag);
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result.create = decode_open_create_flags(oflag);
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result.share = decode_sharing_flags(shflag, result.access);
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result.attributes = FILE_ATTRIBUTE_NORMAL;
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result.flags = 0;
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if (oflag & _O_NOINHERIT)
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{
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result.crt_flags |= FNOINHERIT;
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}
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if (is_text_mode(oflag))
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{
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result.crt_flags |= FTEXT;
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}
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if (oflag & _O_CREAT)
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{
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if (((pmode & ~_umaskval) & _S_IWRITE) == 0)
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result.attributes = FILE_ATTRIBUTE_READONLY;
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}
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if (oflag & _O_TEMPORARY)
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{
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result.flags |= FILE_FLAG_DELETE_ON_CLOSE;
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result.access |= DELETE;
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result.share |= FILE_SHARE_DELETE;
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}
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if (oflag & _O_SHORT_LIVED)
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{
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result.attributes |= FILE_ATTRIBUTE_TEMPORARY;
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}
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if (oflag & _O_OBTAIN_DIR)
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{
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result.flags |= FILE_FLAG_BACKUP_SEMANTICS;
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}
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if (oflag & _O_SEQUENTIAL)
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{
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result.flags |= FILE_FLAG_SEQUENTIAL_SCAN;
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}
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else if (oflag & _O_RANDOM)
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{
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result.flags |= FILE_FLAG_RANDOM_ACCESS;
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}
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return result;
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}
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// If we open a text mode file for writing, and the file ends in Ctrl+Z, we need
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// to remove the Ctrl+Z character so that appending will work. We do this by
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// seeking to the end of the file, testing if the last character is a Ctrl+Z,
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// truncating the file if it is, then rewinding back to the beginning.
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static errno_t truncate_ctrl_z_if_present(int const fh) throw()
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{
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// No truncation is possible for devices and pipes:
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if (_osfile(fh) & (FDEV | FPIPE))
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return 0;
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// No truncation is necessary for binary files:
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if ((_osfile(fh) & FTEXT) == 0)
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return 0;
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// Find the end of the file:
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__int64 const last_char_position = _lseeki64_nolock(fh, -1, SEEK_END);
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// If the seek failed, either the file is empty or an error occurred.
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// (It's not an error if the file is empty.)
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if (last_char_position == -1)
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{
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if (_doserrno == ERROR_NEGATIVE_SEEK)
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return 0;
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return errno;
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}
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// Read the last character. If the read succeeds and the character
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// is a Ctrl+Z, remove the character from the file by shortening:
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wchar_t c = 0;
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if (_read_nolock(fh, &c, 1) == 0 && c == 26)
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{
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if (_chsize_nolock(fh, last_char_position) == -1)
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return errno;
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}
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// Now, rewind the file pointer back to the beginning:
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if (_lseeki64_nolock(fh, 0, SEEK_SET) == -1)
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return errno;
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return 0;
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}
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// Computes the text mode to be used for a file, using a combination of the
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// options passed into the open function and the BOM read from the file.
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static errno_t configure_text_mode(
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int const fh,
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file_options const options,
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int oflag,
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__crt_lowio_text_mode& text_mode
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) throw()
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{
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// The text mode is ANSI by default:
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text_mode = __crt_lowio_text_mode::ansi;
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// If the file is open in binary mode, it gets the default text mode:
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if ((_osfile(fh) & FTEXT) == 0)
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return 0;
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// Set the default text mode per the oflag. The BOM may change the default,
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// if one is present. If oflag does not specify a text mode, use the _fmode
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// default:
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DWORD const text_mode_mask = (_O_TEXT | _O_WTEXT | _O_U16TEXT | _O_U8TEXT);
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if ((oflag & text_mode_mask) == 0)
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{
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int fmode = 0;
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_ERRCHECK(_get_fmode(&fmode));
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if ((fmode & text_mode_mask) == 0)
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oflag |= _O_TEXT; // Default to ANSI.
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else
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oflag |= fmode & text_mode_mask;
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}
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// Now oflags should be set to one of the text modes:
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_ASSERTE((oflag & text_mode_mask) != 0);
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switch (oflag & text_mode_mask)
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{
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case _O_TEXT:
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text_mode = __crt_lowio_text_mode::ansi;
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break;
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case _O_WTEXT:
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case _O_WTEXT | _O_TEXT:
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if ((oflag & (_O_WRONLY | _O_CREAT | _O_TRUNC)) == (_O_WRONLY | _O_CREAT | _O_TRUNC))
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text_mode = __crt_lowio_text_mode::utf16le;
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break;
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case _O_U16TEXT:
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case _O_U16TEXT | _O_TEXT:
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text_mode = __crt_lowio_text_mode::utf16le;
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break;
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case _O_U8TEXT:
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case _O_U8TEXT | _O_TEXT:
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text_mode = __crt_lowio_text_mode::utf8;
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break;
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}
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// If the file hasn't been opened with the UNICODE flags then we have
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// nothing to do: the text mode is the default mode that we just set:
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if ((oflag & (_O_WTEXT | _O_U16TEXT | _O_U8TEXT)) == 0)
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return 0;
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// If this file refers to a device, we cannot check the BOM, so we have
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// nothing to do: the text mode is the default mode that we just set:
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if ((options.crt_flags & FDEV) != 0)
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return 0;
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// Determine whether we need to check or write the BOM, by testing the
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// access with which the file was opened and whether the file already
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// existed or was just created:
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int check_bom = 0;
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int write_bom = 0;
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switch (options.access & GENERIC_READ_WRITE)
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{
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case GENERIC_READ:
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check_bom = 1;
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break;
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case GENERIC_WRITE:
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case GENERIC_READ_WRITE:
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switch (options.create)
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{
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// If this file was opened, we will read the BOM if the file was opened
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// with read/write access. We will write the BOM if and only if the
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// file is empty:
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case OPEN_EXISTING:
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case OPEN_ALWAYS:
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{
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if (_lseeki64_nolock(fh, 0, SEEK_END) != 0)
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{
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if (_lseeki64_nolock(fh, 0, SEEK_SET) == -1)
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return errno;
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// If we have read access, then we need to check the BOM. Note
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// that we've taken a shortcut here: if the file is empty, then
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// we do not set this flag because the file doesn't have a BOM
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// to be read.
|
|
check_bom = (options.access & GENERIC_READ) != 0;
|
|
}
|
|
else
|
|
{
|
|
write_bom = 1;
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
|
|
// If this is a new or truncated file, then we always write the BOM:
|
|
case CREATE_NEW:
|
|
case CREATE_ALWAYS:
|
|
case TRUNCATE_EXISTING:
|
|
{
|
|
write_bom = 1;
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (check_bom)
|
|
{
|
|
int bom = 0;
|
|
int const count = _read_nolock(fh, &bom, UTF8_BOMLEN);
|
|
|
|
// Intrernal validation: This branch should never be taken if write_bom
|
|
// is true and count > 0:
|
|
if (count > 0 && write_bom == 1)
|
|
{
|
|
_ASSERTE(0 && "Internal Error");
|
|
write_bom = 0;
|
|
}
|
|
|
|
switch (count)
|
|
{
|
|
case -1:
|
|
return errno;
|
|
|
|
case UTF8_BOMLEN:
|
|
if (bom == UTF8_BOM)
|
|
{
|
|
text_mode = __crt_lowio_text_mode::utf8;
|
|
break;
|
|
}
|
|
|
|
case UTF16_BOMLEN:
|
|
if((bom & BOM_MASK) == UTF16BE_BOM)
|
|
{
|
|
_ASSERTE(0 && "Only UTF-16 little endian & UTF-8 is supported for reads");
|
|
errno = EINVAL;
|
|
return errno;
|
|
}
|
|
|
|
if((bom & BOM_MASK) == UTF16LE_BOM)
|
|
{
|
|
// We have read three bytes, so we should seek back one byte:
|
|
if(_lseeki64_nolock(fh, UTF16_BOMLEN, SEEK_SET) == -1)
|
|
return errno;
|
|
|
|
text_mode = __crt_lowio_text_mode::utf16le;
|
|
break;
|
|
}
|
|
|
|
// Fall through to default case to lseek to beginning of file
|
|
|
|
default:
|
|
// The file has no BOM, so we seek back to the beginning:
|
|
if (_lseeki64_nolock(fh, 0, SEEK_SET) == -1)
|
|
return errno;
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (write_bom)
|
|
{
|
|
// If we are creating a new file, we write a UTF-16LE or UTF8 BOM:
|
|
int bom_length = 0;
|
|
int bom = 0;
|
|
switch (text_mode)
|
|
{
|
|
case __crt_lowio_text_mode::utf16le:
|
|
{
|
|
bom = UTF16LE_BOM;
|
|
bom_length = UTF16_BOMLEN;
|
|
break;
|
|
}
|
|
case __crt_lowio_text_mode::utf8:
|
|
{
|
|
bom = UTF8_BOM;
|
|
bom_length = UTF8_BOMLEN;
|
|
break;
|
|
}
|
|
}
|
|
|
|
for (int total_written = 0; bom_length > total_written; )
|
|
{
|
|
char const* const bom_begin = reinterpret_cast<char const*>(&bom);
|
|
|
|
// Note that the call to write may write less than bom_length
|
|
// characters but not really fail. We retry until the write fails
|
|
// or we have written all of the characters:
|
|
int const written = _write(fh, bom_begin + total_written, bom_length - total_written);
|
|
if (written == -1)
|
|
return errno;
|
|
|
|
total_written += written;
|
|
}
|
|
}
|
|
|
|
return 0; // Success!
|
|
}
|
|
|
|
|
|
|
|
extern "C" errno_t __cdecl _wsopen_nolock(
|
|
int* const punlock_flag,
|
|
int* const pfh,
|
|
wchar_t const* const path,
|
|
int const oflag,
|
|
int const shflag,
|
|
int const pmode,
|
|
int const secure
|
|
)
|
|
{
|
|
UNREFERENCED_PARAMETER(secure);
|
|
|
|
// First, do the initial parse of the options. The only thing that can fail
|
|
// here is the parsing of the share options, in which case -1 is returned
|
|
// and errno is set.
|
|
file_options options = decode_options(oflag, shflag, pmode);
|
|
if (options.share == static_cast<DWORD>(-1))
|
|
{
|
|
_doserrno = 0;
|
|
*pfh = -1;
|
|
return errno;
|
|
}
|
|
|
|
// Allocate the CRT file handle. Note that if a handle is allocated, it is
|
|
// locked when it is returned by the allocation function. It is our caller's
|
|
// responsibility to unlock the file handle (we do not unlock it before
|
|
// returning).
|
|
*pfh = _alloc_osfhnd();
|
|
if (*pfh == -1)
|
|
{
|
|
_doserrno = 0;
|
|
*pfh = -1;
|
|
errno = EMFILE;
|
|
return errno;
|
|
}
|
|
|
|
// Beyond this point, do not change *pfh, even if an error occurs. Our
|
|
// caller requires the handle in order to release its lock.
|
|
*punlock_flag = 1;
|
|
|
|
|
|
|
|
SECURITY_ATTRIBUTES security_attributes;
|
|
security_attributes.nLength = sizeof(security_attributes);
|
|
security_attributes.lpSecurityDescriptor = nullptr;
|
|
security_attributes.bInheritHandle = (oflag & _O_NOINHERIT) == 0;
|
|
|
|
|
|
// Try to open or create the file:
|
|
HANDLE os_handle = create_file(path, &security_attributes, options);
|
|
if (os_handle == INVALID_HANDLE_VALUE)
|
|
{
|
|
if ((options.access & GENERIC_READ_WRITE) == GENERIC_READ_WRITE && (oflag & _O_WRONLY))
|
|
{
|
|
// The call may have failed because we may be trying to open
|
|
// something for reading that does not allow reading (e.g. a pipe or
|
|
// a device). So, we try again with just GENERIC_WRITE. If this
|
|
// succeeds, we will have to assume the default encoding because we
|
|
// will have no way to read the BOM.
|
|
options.access &= ~GENERIC_READ;
|
|
|
|
os_handle = create_file(path, &security_attributes, options);
|
|
}
|
|
}
|
|
|
|
if (os_handle == INVALID_HANDLE_VALUE)
|
|
{
|
|
// We failed to open the file. We need to free the CRT file handle, but
|
|
// we do not release the lock--our caller releases the lock.
|
|
_osfile(*pfh) &= ~FOPEN;
|
|
__acrt_errno_map_os_error(GetLastError());
|
|
return errno;
|
|
}
|
|
|
|
// Find out what type of file this is (e.g., file, device, pipe, etc.)
|
|
DWORD const file_type = GetFileType(os_handle);
|
|
|
|
if (file_type == FILE_TYPE_UNKNOWN)
|
|
{
|
|
DWORD const last_error = GetLastError();
|
|
__acrt_errno_map_os_error(last_error);
|
|
|
|
_osfile(*pfh) &= ~FOPEN;
|
|
CloseHandle(os_handle);
|
|
|
|
// If GetFileType returns FILE_TYPE_UNKNOWN but doesn't fail, the file
|
|
// type really is unknown. This function is not designed to handle
|
|
// unknown types of files, so we must return an error.
|
|
if (last_error == ERROR_SUCCESS)
|
|
errno = EACCES;
|
|
|
|
return errno;
|
|
}
|
|
|
|
if (file_type == FILE_TYPE_CHAR)
|
|
{
|
|
options.crt_flags |= FDEV;
|
|
}
|
|
else if (file_type == FILE_TYPE_PIPE)
|
|
{
|
|
options.crt_flags |= FPIPE;
|
|
}
|
|
|
|
// The file is open and valid. Set the OS handle:
|
|
__acrt_lowio_set_os_handle(*pfh, reinterpret_cast<intptr_t>(os_handle));
|
|
|
|
|
|
// Mark the handle as open, and store the flags we gathered so far:
|
|
options.crt_flags |= FOPEN;
|
|
_osfile(*pfh) = options.crt_flags;
|
|
|
|
|
|
// The text mode is set to ANSI by default. If we find a BOM, then we will
|
|
// reset this to the appropriate type (this check happens below).
|
|
_textmode(*pfh) = __crt_lowio_text_mode::ansi;
|
|
|
|
|
|
// If the text mode file is opened for writing and allows reading, remove
|
|
// any trailing Ctrl+Z character, if present, to ensure appending works:
|
|
if (oflag & _O_RDWR)
|
|
{
|
|
errno_t const result = truncate_ctrl_z_if_present(*pfh);
|
|
if (result != 0)
|
|
{
|
|
_close_nolock(*pfh);
|
|
return result;
|
|
}
|
|
}
|
|
|
|
// Configure the text mode:
|
|
__crt_lowio_text_mode text_mode = __crt_lowio_text_mode::ansi;
|
|
errno_t const text_mode_result = configure_text_mode(*pfh, options, oflag, text_mode);
|
|
if (text_mode_result != 0)
|
|
{
|
|
_close_nolock(*pfh);
|
|
return text_mode_result;
|
|
}
|
|
|
|
_textmode(*pfh) = text_mode;
|
|
_tm_unicode(*pfh) = (oflag & _O_WTEXT) != 0;
|
|
|
|
|
|
// Set FAPPEND flag if appropriate. Don't do this for devices or pipes:
|
|
if ((options.crt_flags & (FDEV | FPIPE)) == 0 && (oflag & _O_APPEND))
|
|
_osfile(*pfh) |= FAPPEND;
|
|
|
|
|
|
// Finally, if we were asked only to open the file with write access but we
|
|
// opened it with read and write access in order to read the BOM, close the
|
|
// file and re-open it with only write access:
|
|
if ((options.access & GENERIC_READ_WRITE) == GENERIC_READ_WRITE && (oflag & _O_WRONLY))
|
|
{
|
|
CloseHandle(os_handle);
|
|
options.access &= ~GENERIC_READ;
|
|
os_handle = create_file(path, &security_attributes, options);
|
|
|
|
if (os_handle == INVALID_HANDLE_VALUE)
|
|
{
|
|
// Note that we can't use the normal close function here because the
|
|
// file isn't really open anymore. We need only release the file
|
|
// handle by unsetting the FOPEN flag:
|
|
__acrt_errno_map_os_error(GetLastError());
|
|
_osfile(*pfh) &= ~FOPEN;
|
|
_free_osfhnd(*pfh);
|
|
return errno;
|
|
}
|
|
else
|
|
{
|
|
// We were able to open the file successfully, set the file
|
|
// handle in the _ioinfo structure, then we are done. All
|
|
// the options.crt_flags should have been set properly already.
|
|
_osfhnd(*pfh) = reinterpret_cast<intptr_t>(os_handle);
|
|
}
|
|
}
|
|
|
|
return 0; // Success!
|
|
}
|
|
|
|
|
|
|
|
extern "C" errno_t __cdecl _sopen_nolock(
|
|
int* const punlock_flag,
|
|
int* const pfh,
|
|
char const* const path,
|
|
int const oflag,
|
|
int const shflag,
|
|
int const pmode,
|
|
int const secure
|
|
)
|
|
{
|
|
// At this point we know path is not null already
|
|
__crt_internal_win32_buffer<wchar_t> wide_path;
|
|
|
|
errno_t const cvt = __acrt_mbs_to_wcs_cp(path, wide_path, __acrt_get_utf8_acp_compatibility_codepage());
|
|
|
|
if (cvt != 0) {
|
|
return -1;
|
|
}
|
|
|
|
return _wsopen_nolock(punlock_flag, pfh, wide_path.data(), oflag, shflag, pmode, secure);
|
|
}
|
|
|
|
|
|
|
|
extern "C" int __cdecl _sopen(char const* const path, int const oflag, int const shflag, ...)
|
|
{
|
|
va_list ap;
|
|
va_start(ap, shflag);
|
|
int const pmode = va_arg(ap, int);
|
|
va_end(ap);
|
|
|
|
// The last argument is 0 so thta the pmode is not validated in open_s:
|
|
int fh = -1;
|
|
errno_t const result = _sopen_dispatch(path, oflag, shflag, pmode, &fh, FALSE);
|
|
return result ? -1 : fh;
|
|
}
|
|
|
|
extern "C" int __cdecl _wsopen(wchar_t const* const path, int const oflag, int const shflag, ...)
|
|
{
|
|
va_list ap;
|
|
va_start(ap, shflag);
|
|
int const pmode = va_arg(ap, int);
|
|
va_end(ap);
|
|
|
|
// The last argument is 0 so thta the pmode is not validated in open_s:
|
|
int fh = -1;
|
|
errno_t const result = _wsopen_dispatch(path, oflag, shflag, pmode, &fh, FALSE);
|
|
return result ? -1 : fh;
|
|
}
|
|
|
|
|
|
|
|
extern "C" errno_t __cdecl _sopen_s(
|
|
int* const pfh,
|
|
char const* const path,
|
|
int const oflag,
|
|
int const shflag,
|
|
int const pmode
|
|
)
|
|
{
|
|
// The last argument is 1 so that pmode is validated in open_s:
|
|
return _sopen_dispatch(path, oflag, shflag, pmode, pfh, TRUE);
|
|
}
|
|
|
|
extern "C" errno_t __cdecl _wsopen_s(
|
|
int* const pfh,
|
|
wchar_t const* const path,
|
|
int const oflag,
|
|
int const shflag,
|
|
int const pmode
|
|
)
|
|
{
|
|
// The last argument is 1 so that pmode is validated in open_s:
|
|
return _wsopen_dispatch(path, oflag, shflag, pmode, pfh, TRUE);
|
|
}
|