win32setlocale.c

Go to the documentation of this file.

/*-------------------------------------------------------------------------
 *
 * win32setlocale.c
 *      Wrapper to work around bugs in Windows setlocale() implementation
 *
 * Copyright (c) 2011-2013, PostgreSQL Global Development Group
 *
 * IDENTIFICATION
 *    src/port/win32setlocale.c
 *
 *
 * Windows has a problem with locale names that have a dot in the country
 * name. For example:
 *
 * "Chinese (Traditional)_Hong Kong S.A.R..950"
 *
 * For some reason, setlocale() doesn't accept that. Fortunately, Windows'
 * setlocale() accepts various alternative names for such countries, so we
 * provide a wrapper setlocale() function that maps the troublemaking locale
 * names to accepted aliases.
 *-------------------------------------------------------------------------
 */

#include "c.h"

#undef setlocale

struct locale_map
{
    const char *locale_name_part;       /* string in locale name to replace */
    const char *replacement;    /* string to replace it with */
};

static const struct locale_map locale_map_list[] = {
    /*
     * "HKG" is listed here:
     * http://msdn.microsoft.com/en-us/library/cdax410z%28v=vs.71%29.aspx
     * (Country/Region Strings).
     *
     * "ARE" is the ISO-3166 three-letter code for U.A.E. It is not on the
     * above list, but seems to work anyway.
     */
    {"Hong Kong S.A.R.", "HKG"},
    {"U.A.E.", "ARE"},

    /*
     * The ISO-3166 country code for Macau S.A.R. is MAC, but Windows doesn't
     * seem to recognize that. And Macau isn't listed in the table of accepted
     * abbreviations linked above. Fortunately, "ZHM" seems to be accepted as
     * an alias for "Chinese (Traditional)_Macau S.A.R..950". I'm not sure
     * where "ZHM" comes from, must be some legacy naming scheme. But hey, it
     * works.
     *
     * Note that unlike HKG and ARE, ZHM is an alias for the *whole* locale
     * name, not just the country part.
     *
     * Some versions of Windows spell it "Macau", others "Macao".
     */
    {"Chinese (Traditional)_Macau S.A.R..950", "ZHM"},
    {"Chinese_Macau S.A.R..950", "ZHM"},
    {"Chinese (Traditional)_Macao S.A.R..950", "ZHM"},
    {"Chinese_Macao S.A.R..950", "ZHM"}
};

char *
pgwin32_setlocale(int category, const char *locale)
{
    char       *result;
    char       *alias;
    int         i;

    if (locale == NULL)
        return setlocale(category, locale);

    /* Check if the locale name matches any of the problematic ones. */
    alias = NULL;
    for (i = 0; i < lengthof(locale_map_list); i++)
    {
        const char *needle = locale_map_list[i].locale_name_part;
        const char *replacement = locale_map_list[i].replacement;
        char       *match;

        match = strstr(locale, needle);
        if (match != NULL)
        {
            /* Found a match. Replace the matched string. */
            int         matchpos = match - locale;
            int         replacementlen = strlen(replacement);
            char       *rest = match + strlen(needle);
            int         restlen = strlen(rest);

            alias = malloc(matchpos + replacementlen + restlen + 1);
            if (!alias)
                return NULL;

            memcpy(&alias[0], &locale[0], matchpos);
            memcpy(&alias[matchpos], replacement, replacementlen);
            memcpy(&alias[matchpos + replacementlen], rest, restlen + 1);       /* includes null
                                                                                 * terminator */

            break;
        }
    }

    /* Call the real setlocale() function */
    if (alias)
    {
        result = setlocale(category, alias);
        free(alias);
    }
    else
        result = setlocale(category, locale);

    return result;
}