windows-nt/Source/XPSP1/NT/base/crts/crtw32/mbstring/mbschr.c
2020-09-26 16:20:57 +08:00

98 lines
2.6 KiB
C

/***
* mbschr.c - Search MBCS string for character
*
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* Search MBCS string for a character
*
*Revision History:
* 11-19-92 KRS Ported from 16-bit sources.
* 05-12-93 KRS Fix handling of c=='\0'.
* 08-20-93 CFW Change param type to int, use new style param declarators.
* 10-05-93 GJF Replaced _CRTAPI1 with __cdecl.
* 04-15-93 CFW Add _MB_CP_LOCK.
* 05-09-94 CFW Optimize for SBCS.
* 05-19-94 CFW Enable non-Win32.
* 09-11-97 GJF Replaced __mbcodepage == 0 with _ISNOTMBCP.
* 04-06-98 GJF Revised multithread support based on threadmbcinfo
* structs
*
*******************************************************************************/
#ifdef _MBCS
#include <mtdll.h>
#include <cruntime.h>
#include <string.h>
#include <mbdata.h>
#include <mbctype.h>
#include <mbstring.h>
#include <stddef.h>
/***
* _mbschr - Search MBCS string for character
*
*Purpose:
* Search the given string for the specified character.
* MBCS characters are handled correctly.
*
*Entry:
* unsigned char *string = string to search
* int c = character to search for
*
*Exit:
* returns a pointer to the first occurence of the specified char
* within the string.
*
* returns NULL if the character is not found n the string.
*
*Exceptions:
*
*******************************************************************************/
unsigned char * __cdecl _mbschr(
const unsigned char *string,
unsigned int c
)
{
unsigned short cc;
#ifdef _MT
pthreadmbcinfo ptmbci = _getptd()->ptmbcinfo;
if ( ptmbci != __ptmbcinfo )
ptmbci = __updatetmbcinfo();
if ( _ISNOTMBCP_MT(ptmbci) )
#else
if ( _ISNOTMBCP )
#endif
return strchr(string, c);
for (; (cc = *string); string++)
{
#ifdef _MT
if ( __ismbblead_mt(ptmbci, cc) )
#else
if ( _ismbblead(cc) )
#endif
{
if (*++string == '\0')
return NULL; /* error */
if ( c == (unsigned int)((cc << 8) | *string) ) /* DBCS match */
return (unsigned char *)(string - 1);
}
else if (c == (unsigned int)cc)
break; /* SBCS match */
}
if (c == (unsigned int)cc) /* check for SBCS match--handles NUL char */
return (unsigned char *)(string);
return NULL;
}
#endif /* _MBCS */