initctyp.c

C标准库源代码

/***
*initctyp.c - contains __init_ctype
*
*       Copyright (c) 1991-1998, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       Contains the locale-category initialization function: __init_ctype().
*
*       Each initialization function sets up locale-specific information
*       for their category, for use by functions which are affected by
*       their locale category.
*
*       *** For internal use by setlocale() only ***
*
*******************************************************************************/

#include <stdlib.h>
#include <windows.h>
#include <locale.h>
#include <setlocal.h>
#include <ctype.h>
#include <malloc.h>
#include <limits.h>
#include <awint.h>
#include <dbgint.h>

#define _CTABSIZE   257     /* size of ctype tables */

/***
*int __init_ctype() - initialization for LC_CTYPE locale category.
*
*Purpose:
*       In non-C locales, preread ctype tables for chars and wide-chars.
*       Old tables are freed when new tables are fully established, else
*       the old tables remain intact (as if original state unaltered).
*       The leadbyte table is implemented as the high bit in ctype1.
*
*       In the C locale, ctype tables are freed, and pointers point to
*       the static ctype table.
*
*       Tables contain 257 entries: -1 to 256.
*       Table pointers point to entry 0 (to allow index -1).
*
*Entry:
*       None.
*
*Exit:
*       0 success
*       1 fail
*
*Exceptions:
*
*******************************************************************************/

int __cdecl __init_ctype (
        void
        )
{
        /* non-C locale table for char's    */
        static unsigned short *ctype1 = NULL;   /* keep around until next time */
        unsigned short *newctype1;          /* temp new table */

        /* non-C locale table for wchar_t's */
        static unsigned short *wctype1 = NULL;  /* keep around until next time */
        unsigned short *newwctype1;         /* temp new table */

        unsigned char *cbuffer = NULL;      /* char working buffer */
        wchar_t *wbuffer = NULL;            /* wchar_t working buffer */

        int i;                              /* general purpose counter */
        unsigned char *cp;                  /* char pointer */
        wchar_t *wcp;                       /* wide char pointer */
        CPINFO lpCPInfo;                    /* struct for use with GetCPInfo */

        /* allocate and set up buffers before destroying old ones */
        /* codepage will be restored by setlocale if error */


        if (__lc_handle[LC_CTYPE] != _CLOCALEHANDLE)
        {
            if (__lc_codepage == 0)
            { /* code page was not specified */
                if ( __getlocaleinfo( LC_INT_TYPE,
                                      MAKELCID(__lc_id[LC_CTYPE].wLanguage, SORT_DEFAULT),
                                      LOCALE_IDEFAULTANSICODEPAGE,
                                      (char **)&__lc_codepage ) )
                    goto error_cleanup;
            }

            /* allocate new buffers for tables */
            newctype1 = (unsigned short *)
                _malloc_crt(_CTABSIZE * sizeof(unsigned short));
            newwctype1 = (unsigned short *)
                _malloc_crt(_CTABSIZE * sizeof(unsigned short));
            cbuffer = (unsigned char *)
                _malloc_crt (_CTABSIZE * sizeof(char));
            wbuffer = (wchar_t *)
                _malloc_crt (_CTABSIZE * sizeof(wchar_t));

            if (!newctype1 || !newwctype1 || !cbuffer || !wbuffer)
                goto error_cleanup;

            /* construct string composed of first 256 chars in sequence */
            for (cp=cbuffer, i=0; i<_CTABSIZE-1; i++)
                *cp++ = (unsigned char)i;

            if (GetCPInfo( __lc_codepage, &lpCPInfo) == FALSE)
                goto error_cleanup;

            if (lpCPInfo.MaxCharSize > MB_LEN_MAX)
                goto error_cleanup;

            __mb_cur_max = (unsigned short) lpCPInfo.MaxCharSize;

            /* zero out leadbytes so GetStringType doesn't interpret as multi-byte chars */
            if (__mb_cur_max > 1)
            {
                for (cp = (unsigned char *)lpCPInfo.LeadByte; cp[0] && cp[1]; cp += 2)
                {
                    for (i = cp[0]; i <= cp[1]; i++)
                        cbuffer[i] = 0;
                }
            }

            /* convert to newctype1 table - ignore invalid char errors */
            if ( __crtGetStringTypeA( CT_CTYPE1,
                                      cbuffer,
                                      _CTABSIZE-1,
                                      newctype1+1,
                                      0,
                                      0,
                                      FALSE ) == FALSE )
                goto error_cleanup;
            *newctype1 = 0; /* entry for EOF */

            /* construct wide char string composed of first 256 chars in sequence */
            for (wcp=wbuffer, i=0; i<_CTABSIZE-1; i++)
                *wcp++ = (wchar_t)i;

            /* convert to newwctype1 table */
            if ( __crtGetStringTypeW( CT_CTYPE1,
                                      wbuffer,
                                      _CTABSIZE-1,
                                      newwctype1+1,
                                      0,
                                      0 ) == FALSE )
                goto error_cleanup;
            *newwctype1 = 0;    /* entry for EOF */

            /* ignore DefaultChar */

            /* mark lead-byte entries in newctype1 table */
            if (__mb_cur_max > 1)
            {
                for (cp = (unsigned char *)lpCPInfo.LeadByte; cp[0] && cp[1]; cp += 2)
                {
                    for (i = cp[0]; i <= cp[1]; i++)
                        newctype1[i+1] = _LEADBYTE;
                }
            }

            /* set pointers to point to entry 0 of tables */
            _pctype = newctype1 + 1;
            _pwctype = newwctype1 + 1;

            /* free old tables */
            if (ctype1)
                _free_crt (ctype1);
            ctype1 = newctype1;

            if (wctype1)
                _free_crt (wctype1);
            wctype1 = newwctype1;

            /* cleanup and return success */
            _free_crt (cbuffer);
            _free_crt (wbuffer);
            return 0;

error_cleanup:
            _free_crt (newctype1);
            _free_crt (newwctype1);
            _free_crt (cbuffer);
            _free_crt (wbuffer);
            return 1;

        } else {

            /* set pointers to static C-locale table */
            _pctype = _ctype + 1;
            _pwctype = _ctype + 1;

            /* free dynamic locale-specific tables */
            _free_crt (ctype1);
            _free_crt (wctype1);
            ctype1 = NULL;
            wctype1 = NULL;

            return 0;
        }
}