ngx_http_browser_module.c

nginx 反向代理0.7.1版本 用于实现反向代理

        }
    }

    if (cf->ancient_browsers) {
        ancient = cf->ancient_browsers->elts;

        for (i = 0; i < cf->ancient_browsers->nelts; i++) {
            if (len >= ancient[i].len
                && ngx_strstr(ua, ancient[i].data) != NULL)
            {
                return NGX_HTTP_ANCIENT_BROWSER;
            }
        }
    }

    if (cf->modern_unlisted_browsers) {
        return NGX_HTTP_MODERN_BROWSER;
    }

    return NGX_HTTP_ANCIENT_BROWSER;
}


static ngx_int_t
ngx_http_msie_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v,
    uintptr_t data)
{
    if (r->headers_in.msie) {
        *v = ngx_http_variable_true_value;
        return NGX_OK;
    }

    *v = ngx_http_variable_null_value;
    return NGX_OK;
}


static ngx_int_t
ngx_http_browser_add_variable(ngx_conf_t *cf)
{
    ngx_http_browser_variable_t   *var;
    ngx_http_variable_t           *v;

    for (var = ngx_http_browsers; var->name.len; var++) {

        v = ngx_http_add_variable(cf, &var->name, NGX_HTTP_VAR_CHANGEABLE);
        if (v == NULL) {
            return NGX_ERROR;
        }

        v->get_handler = var->handler;
        v->data = var->data;
    }

    return NGX_OK;
}


static void *
ngx_http_browser_create_conf(ngx_conf_t *cf)
{
    ngx_http_browser_conf_t  *conf;

    conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_browser_conf_t));
    if (conf == NULL) {
        return NGX_CONF_ERROR;
    }

    /*
     * set by ngx_pcalloc():
     *
     *     conf->modern_browsers = NULL;
     *     conf->ancient_browsers = NULL;
     *     conf->modern_browser_value = NULL;
     *     conf->ancient_browser_value = NULL;
     *
     *     conf->modern_unlisted_browsers = 0;
     *     conf->netscape4 = 0;
     */

    return conf;
}


static char *
ngx_http_browser_merge_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_http_browser_conf_t *prev = parent;
    ngx_http_browser_conf_t *conf = child;

    ngx_uint_t                  i, n;
    ngx_http_modern_browser_t  *browsers, *opera;

    /*
     * At the merge the skip field is used to store the browser slot,
     * it will be used in sorting and then will overwritten
     * with a real skip value.  The zero value means Opera.
     */

    if (conf->modern_browsers == NULL) {
        conf->modern_browsers = prev->modern_browsers;

    } else {
        browsers = conf->modern_browsers->elts;

        for (i = 0; i < conf->modern_browsers->nelts; i++) {
            if (browsers[i].skip == 0) {
                goto found;
            }
        }

        /*
         * Opera may contain MSIE string, so if Opera was not enumerated
         * as modern browsers, then add it and set a unreachable version
         */

        opera = ngx_array_push(conf->modern_browsers);
        if (opera == NULL) {
            return NGX_CONF_ERROR;
        }

        opera->skip = 0;
        opera->version = 4001000000U;

        browsers = conf->modern_browsers->elts;

found:

        ngx_qsort(browsers, (size_t) conf->modern_browsers->nelts,
                  sizeof(ngx_http_modern_browser_t),
                  ngx_http_modern_browser_sort);

        for (i = 0; i < conf->modern_browsers->nelts; i++) {
             n = browsers[i].skip;

             browsers[i].skip = ngx_http_modern_browser_masks[n].skip;
             browsers[i].add = ngx_http_modern_browser_masks[n].add;
             (void) ngx_cpystrn(browsers[i].name,
                                ngx_http_modern_browser_masks[n].name, 12);
        }
    }

    if (conf->ancient_browsers == NULL) {
        conf->ancient_browsers = prev->ancient_browsers;
    }

    if (conf->modern_browser_value == NULL) {
        conf->modern_browser_value = prev->modern_browser_value;
    }

    if (conf->modern_browser_value == NULL) {
        conf->modern_browser_value = &ngx_http_variable_true_value;
    }

    if (conf->ancient_browser_value == NULL) {
        conf->ancient_browser_value = prev->ancient_browser_value;
    }

    if (conf->ancient_browser_value == NULL) {
        conf->ancient_browser_value = &ngx_http_variable_true_value;
    }

    return NGX_CONF_OK;
}


static int ngx_libc_cdecl
ngx_http_modern_browser_sort(const void *one, const void *two)
{
    ngx_http_modern_browser_t *first = (ngx_http_modern_browser_t *) one;
    ngx_http_modern_browser_t *second = (ngx_http_modern_browser_t *) two;

    return (first->skip - second->skip);
}


static char *
ngx_http_modern_browser(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_browser_conf_t *bcf = conf;

    u_char                           c;
    ngx_str_t                       *value;
    ngx_uint_t                       i, n, version, ver, scale;
    ngx_http_modern_browser_t       *browser;
    ngx_http_modern_browser_mask_t  *mask;

    value = cf->args->elts;

    if (cf->args->nelts == 2) {
        if (ngx_strcmp(value[1].data, "unlisted") == 0) {
            bcf->modern_unlisted_browsers = 1;
            return NGX_CONF_OK;
        }

        return NGX_CONF_ERROR;
    }

    if (bcf->modern_browsers == NULL) {
        bcf->modern_browsers = ngx_array_create(cf->pool, 5,
                                            sizeof(ngx_http_modern_browser_t));
        if (bcf->modern_browsers == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    browser = ngx_array_push(bcf->modern_browsers);
    if (browser == NULL) {
        return NGX_CONF_ERROR;
    }

    mask = ngx_http_modern_browser_masks;

    for (n = 0; mask[n].browser[0] != '\0'; n++) {
        if (ngx_strcasecmp(mask[n].browser, value[1].data) == 0) {
            goto found;
        }
    }

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "unknown browser name \"%V\"", &value[1]);

    return NGX_CONF_ERROR;

found:

    /*
     * at this stage the skip field is used to store the browser slot,
     * it will be used in sorting in merge stage and then will overwritten
     * with a real value
     */

    browser->skip = n;

    version = 0;
    ver = 0;
    scale = 1000000;

    for (i = 0; i < value[2].len; i++) {

        c = value[2].data[i];

        if (c >= '0' && c <= '9') {
            ver = ver * 10 + (c - '0');
            continue;
        }

        if (c == '.') {
            version += ver * scale;
            ver = 0;
            scale /= 100;
            continue;
        }

        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid browser version \"%V\"", &value[2]);

        return NGX_CONF_ERROR;
    }

    version += ver * scale;

    browser->version = version;

    return NGX_CONF_OK;
}


static char *
ngx_http_ancient_browser(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_browser_conf_t *bcf = conf;

    ngx_str_t   *value, *browser;
    ngx_uint_t   i;

    value = cf->args->elts;

    for (i = 1; i < cf->args->nelts; i++) {
        if (ngx_strcmp(value[i].data, "netscape4") == 0) {
            bcf->netscape4 = 1;
            continue;
        }

        if (bcf->ancient_browsers == NULL) {
            bcf->ancient_browsers = ngx_array_create(cf->pool, 4,
                                                     sizeof(ngx_str_t));
            if (bcf->ancient_browsers == NULL) {
                return NGX_CONF_ERROR;
            }
        }

        browser = ngx_array_push(bcf->ancient_browsers);
        if (browser == NULL) {
            return NGX_CONF_ERROR;
        }

        *browser = value[i];
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_modern_browser_value(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_browser_conf_t *bcf = conf;

    ngx_str_t  *value;

    bcf->modern_browser_value = ngx_palloc(cf->pool,
                                           sizeof(ngx_http_variable_value_t));
    if (bcf->modern_browser_value == NULL) {
        return NGX_CONF_ERROR;
    }

    value = cf->args->elts;

    bcf->modern_browser_value->len = value[1].len;
    bcf->modern_browser_value->valid = 1;
    bcf->modern_browser_value->no_cacheable = 0;
    bcf->modern_browser_value->not_found = 0;
    bcf->modern_browser_value->data = value[1].data;

    return NGX_CONF_OK;
}


static char *
ngx_http_ancient_browser_value(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_browser_conf_t *bcf = conf;

    ngx_str_t  *value;

    bcf->ancient_browser_value = ngx_palloc(cf->pool,
                                            sizeof(ngx_http_variable_value_t));
    if (bcf->ancient_browser_value == NULL) {
        return NGX_CONF_ERROR;
    }

    value = cf->args->elts;

    bcf->ancient_browser_value->len = value[1].len;
    bcf->ancient_browser_value->valid = 1;
    bcf->ancient_browser_value->no_cacheable = 0;
    bcf->ancient_browser_value->not_found = 0;
    bcf->ancient_browser_value->data = value[1].data;

    return NGX_CONF_OK;
}