view src/os/win32/ngx_errno.c @ 7585:746567d633ac

Win32: improved fallback on FormatMessage() errors. FormatMessage() seems to return many errors which essentially indicate that the language in question is not available. At least the following were observed in the wild and during testing: ERROR_MUI_FILE_NOT_FOUND (15100) (ticket #1868), ERROR_RESOURCE_TYPE_NOT_FOUND (1813). While documentation says it should be ERROR_RESOURCE_LANG_NOT_FOUND (1815), this doesn't seem to be the case. As such, checking error code was removed, and as long as FormatMessage() returns an error, we now always try the default language.
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 21 Oct 2019 19:06:12 +0300
parents f1a0de6eb505
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>


u_char *
ngx_strerror(ngx_err_t err, u_char *errstr, size_t size)
{
    u_int          len;
    static u_long  lang = MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US);

    if (size == 0) {
        return errstr;
    }

    len = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM,
                        NULL, err, lang, (char *) errstr, size, NULL);

    if (len == 0 && lang) {

        /*
         * Try to use English messages first and fallback to a language,
         * based on locale: non-English Windows have no English messages
         * at all.  This way allows to use English messages at least on
         * Windows with MUI.
         */

        lang = 0;

        len = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM,
                            NULL, err, lang, (char *) errstr, size, NULL);
    }

    if (len == 0) {
        return ngx_snprintf(errstr, size,
                            "FormatMessage() error:(%d)", GetLastError());
    }

    /* remove ".\r\n\0" */
    while (errstr[len] == '\0' || errstr[len] == CR
           || errstr[len] == LF || errstr[len] == '.')
    {
        --len;
    }

    return &errstr[++len];
}


ngx_int_t
ngx_strerror_init(void)
{
    return NGX_OK;
}