char const* template_formatter::next_specifier(output_buffer* pbuffer,
char const* pformat)
{
#ifdef _GNU_SOURCE
while(true) {
char const* pspecifier = strchrnul(pformat, '%');
auto len = pspecifier - pformat;
auto p = pbuffer->reserve(len);
std::memcpy(p, pformat, len);
pbuffer->commit(len);
if(*pspecifier == '\0')
return nullptr;
pformat = pspecifier + 1;
if(*pformat != '%')
return pformat;
// Found "%%". Add a single '%' and continue.
++pformat;
append_percent(pbuffer);
}
#else
static_assert(false, "need replacement for strchrnul");
#endif
}
void template_formatter::format(output_buffer* pbuffer, char const* pformat)
{
// There are no remaining arguments to format, so we will ignore additional
// format specifications that might occur in the format string. However, we
// still need to treat "%%" as "%". We'll iterate over on next_specifier
// and when it finds a format specifier, we append a '%' and move on.
while((pformat = next_specifier(pbuffer, pformat)) != nullptr)
append_percent(pbuffer);
}
static void format(output_buffer* pbuffer, char const* pformat,
T&& value, Args&&... args)
{
pformat = next_specifier(pbuffer, pformat);
if(not pformat)
return;
char const* pnext_format = detail::invoke_custom_format(pbuffer,
pformat, std::forward<T>(value));
if(pnext_format)
pformat = pnext_format;
else
append_percent(pbuffer);
return template_formatter::format(pbuffer, pformat,
std::forward<Args>(args)...);
}