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/***
*w_cmp.c - W versions of CompareString.** Copyright (c) 1993-2001, Microsoft Corporation. All rights reserved.**Purpose:* Use either CompareStringA or CompareStringW depending on which is * available**Revision History:* 09-14-93 CFW Module created.* 09-17-93 CFW Use unsigned chars.* 09-23-93 CFW Correct NLS API params and comments about same.* 10-07-93 CFW Optimize WideCharToMultiByte, use NULL default char.* 10-22-93 CFW Test for invalid MB chars using global preset flag.* 11-09-93 CFW Allow user to pass in code page.* 11-18-93 CFW Test for entry point function stubs.* 02-23-94 CFW Use W flavor whenever possible.* 03-31-94 CFW Include awint.h.* 05-09-94 CFW Do not let CompareString compare past NULL.* 06-03-94 CFW Test for empty string early.* 11/01-94 CFW But not too early for MB strings.* 12-21-94 CFW Remove invalid MB chars NT 3.1 hack.* 12-27-94 CFW Call direct, all OS's have stubs.* 01-10-95 CFW Debug CRT allocs.* 02-06-95 CFW assert -> _ASSERTE.* 02-15-97 RDK For narrow comparsion, try W version first so Windows NT* can process nonANSI codepage correctly.* 05-15-97 GJF Split off from aw_cmp.c. Replaced use of _malloc_crt* and _free_crt with _alloca. Also, detab-ed and cleaned* up the code a bit.* 05-27-98 GJF Changed wcsncnt() so that it will never examine the* (cnt + 1)-th byte of the string.* 08-18-98 GJF Use _malloc_crt if _alloca fails.* 04-28-99 GJF Changed dwFlags arg value to 0 in WideCharToMultiByte* calls to avoid problems with codepage 1258 on NT 5.0.* 12-10-99 GB Added support for recovery from stack overflow around * _alloca().* 05-17-00 GB Use ERROR_CALL_NOT_IMPLEMENTED for existance of W API* 08-23-00 GB Fixed bug with non Ansi CP on Win9x.********************************************************************************/
#include <cruntime.h>
#include <internal.h>
#include <dbgint.h>
#include <stdlib.h>
#include <setlocal.h>
#include <locale.h>
#include <awint.h>
#include <dbgint.h>
#include <malloc.h>
#define USE_W 1
#define USE_A 2
/***
*int __cdecl wcsncnt - count wide characters in a string, up to n.**Purpose:* Internal local support function. Counts characters in string before NULL.* If NULL not found in n chars, then return n.**Entry:* const wchar_t *string - start of string* int n - byte count**Exit:* returns number of wide characaters from start of string to* NULL (exclusive), up to n.**Exceptions:********************************************************************************/
static int __cdecl wcsncnt ( const wchar_t *string, int cnt ){ int n = cnt; wchar_t *cp = (wchar_t *)string;
while (n-- && *cp) cp++;
return cnt - n - 1;}
/***
*int __cdecl __crtCompareStringW - Get type information about a wide string.**Purpose:* Internal support function. Assumes info in wide string format. Tries* to use NLS API call CompareStringW if available and uses CompareStringA* if it must. If neither are available it fails and returns 0.**Entry:* LCID Locale - locale context for the comparison.* DWORD dwCmpFlags - see NT\Chicago docs* LPCWSTR lpStringn - wide string to be compared* int cchCountn - wide char (word) count (NOT including NULL)* (-1 if NULL terminated)* int code_page - for MB/WC conversion. If 0, use __lc_codepage**Exit:* Success: 1 - if lpString1 < lpString2* 2 - if lpString1 == lpString2* 3 - if lpString1 > lpString2* Failure: 0**Exceptions:********************************************************************************/
int __cdecl __crtCompareStringW( LCID Locale, DWORD dwCmpFlags, LPCWSTR lpString1, int cchCount1, LPCWSTR lpString2, int cchCount2, int code_page ){ static int f_use = 0;
/*
* Look for unstubbed 'preferred' flavor. Otherwise use available flavor. * Must actually call the function to ensure it's not a stub. */ if (0 == f_use) { if (0 != CompareStringW(0, 0, L"\0", 1, L"\0", 1)) f_use = USE_W;
else if (GetLastError() == ERROR_CALL_NOT_IMPLEMENTED) f_use = USE_A; }
/*
* CompareString will compare past NULL. Must find NULL if in string * before cchCountn wide characters. */
if (cchCount1 > 0) cchCount1= wcsncnt(lpString1, cchCount1); if (cchCount2 > 0) cchCount2= wcsncnt(lpString2, cchCount2);
if (!cchCount1 || !cchCount2) return (cchCount1 - cchCount2 == 0) ? 2 : (cchCount1 - cchCount2 < 0) ? 1 : 3;
/* Use "W" version */
if (USE_W == f_use) { return CompareStringW( Locale, dwCmpFlags, lpString1, cchCount1, lpString2, cchCount2 ); }
/* Use "A" version */
if (USE_A == f_use || f_use == 0) { int buff_size1; int buff_size2; unsigned char *buffer1; unsigned char *buffer2; int retcode = 0; int malloc_flag1 = 0; int malloc_flag2 = 0; int AnsiCP;
/*
* Use __lc_codepage for conversion if code_page not specified */
if (0 == Locale) Locale = __lc_handle[LC_CTYPE]; if (0 == code_page) code_page = __lc_codepage;
/*
* Always use Ansi codepage with Ansi WinAPI because they use * Ansi codepage */ if ( code_page != (AnsiCP = __ansicp(Locale))) { if (AnsiCP != -1) code_page = AnsiCP; }
/*
* Convert strings and return the requested information. */
/* find out how big a buffer we need (includes NULL if any) */ if ( 0 == (buff_size1 = WideCharToMultiByte( code_page, 0, lpString1, cchCount1, NULL, 0, NULL, NULL )) ) return 0;
/* allocate enough space for chars */ __try { buffer1 = (unsigned char *)_alloca( buff_size1 * sizeof(char) ); } __except( EXCEPTION_EXECUTE_HANDLER ) { _resetstkoflw(); buffer1 = NULL; }
if ( buffer1 == NULL ) { if ( (buffer1 = (unsigned char *)_malloc_crt(buff_size1 * sizeof(char))) == NULL ) return 0; malloc_flag1++; }
/* do the conversion */ if ( 0 == WideCharToMultiByte( code_page, 0, lpString1, cchCount1, buffer1, buff_size1, NULL, NULL ) ) goto error_cleanup;
/* find out how big a buffer we need (includes NULL if any) */ if ( 0 == (buff_size2 = WideCharToMultiByte( code_page, 0, lpString2, cchCount2, NULL, 0, NULL, NULL )) ) goto error_cleanup;
/* allocate enough space for chars */ __try { buffer2 = (unsigned char *)_alloca( buff_size2 * sizeof(char) ); } __except( EXCEPTION_EXECUTE_HANDLER ) { _resetstkoflw(); buffer2 = NULL; }
if ( buffer2 == NULL ) { if ( (buffer2 = (unsigned char *)_malloc_crt(buff_size2 * sizeof(char))) == NULL ) goto error_cleanup; malloc_flag2++; }
/* do the conversion */ if ( 0 != WideCharToMultiByte( code_page, 0, lpString2, cchCount2, buffer2, buff_size2, NULL, NULL ) ) retcode = CompareStringA( Locale, dwCmpFlags, buffer1, buff_size1, buffer2, buff_size2 );
if ( malloc_flag2 ) _free_crt(buffer2);
error_cleanup: if ( malloc_flag1 ) _free_crt(buffer1);
return retcode; } else /* f_use is neither USE_A nor USE_W */ return 0;}
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