ngx_int_t
ngx_http_arg(ngx_http_request_t *r, u_char *name, size_t len, ngx_str_t *value)
{
    u_char  *p, *last;
    if (r->args.len == 0) {
        return NGX_DECLINED;
    }
    p = r->args.data;
    last = p + r->args.len;
    for (   ; p < last; p++) {
        p = ngx_strlcasestrn(p, last - 1, name, len - 1);
        if (p == NULL) {
            return NGX_DECLINED;
        }
        if ((p == r->args.data || *(p - 1) == '&') && *(p + len) == '=') {
            value->data = p + len + 1;
            p = ngx_strlchr(p, last, '&');
            if (p == NULL) {
                p = r->args.data + r->args.len;
            }
            value->len = p - value->data;
            return NGX_OK;
        }
    }
    return NGX_DECLINED;
}
['static ngx_int_t\nngx_http_variable_argument(ngx_http_request_t *r, ngx_http_variable_value_t *v,\n    uintptr_t data)\n{\n    ngx_str_t *name = (ngx_str_t *) data;\n    u_char     *arg;\n    size_t      len;\n    ngx_str_t   value;\n    len = name->len - (sizeof("arg_") - 1);\n    arg = name->data + sizeof("arg_") - 1;\n    if (ngx_http_arg(r, arg, len, &value) != NGX_OK) {\n        v->not_found = 1;\n        return NGX_OK;\n    }\n    v->data = value.data;\n    v->len = value.len;\n    v->valid = 1;\n    v->no_cacheable = 0;\n    v->not_found = 0;\n    return NGX_OK;\n}', "ngx_int_t\nngx_http_arg(ngx_http_request_t *r, u_char *name, size_t len, ngx_str_t *value)\n{\n    u_char  *p, *last;\n    if (r->args.len == 0) {\n        return NGX_DECLINED;\n    }\n    p = r->args.data;\n    last = p + r->args.len;\n    for (   ; p < last; p++) {\n        p = ngx_strlcasestrn(p, last - 1, name, len - 1);\n        if (p == NULL) {\n            return NGX_DECLINED;\n        }\n        if ((p == r->args.data || *(p - 1) == '&') && *(p + len) == '=') {\n            value->data = p + len + 1;\n            p = ngx_strlchr(p, last, '&');\n            if (p == NULL) {\n                p = r->args.data + r->args.len;\n            }\n            value->len = p - value->data;\n            return NGX_OK;\n        }\n    }\n    return NGX_DECLINED;\n}"]