#include "source/common/http/http2/nghttp2.h"

#include "source/common/common/logger.h"

// nghttp2 fails to convey the POSIX ssize_t declaration

// that Microsoft declines to implement. Pick up a valid

// ssize_t declaration for win32 in our platform.h

#include "envoy/common/platform.h"

#include "nghttp2/nghttp2.h"

namespace Envoy {

namespace Http {

namespace Http2 {

void initializeNghttp2Logging() {

  // When ENVOY_NGHTTP2_TRACE is set, we install a debug logger, to prevent nghttp2

  // logging directly to stdout at -l trace.

  nghttp2_set_debug_vprintf_callback([](const char* format, va_list args) {

    if (std::getenv("ENVOY_NGHTTP2_TRACE") != nullptr) {

      char buf[2048];

      const int n = ::vsnprintf(buf, sizeof(buf), format, args);

      // nghttp2 inserts new lines, but we also insert a new line in the ENVOY_LOG

      // below, so avoid double \n.

      if (n >= 1 && static_cast<size_t>(n) < sizeof(buf) && buf[n - 1] == '\n') {

        buf[n - 1] = '\0';

      }

      ENVOY_LOG_TO_LOGGER(Logger::Registry::getLog(Logger::Id::http2), trace, "nghttp2: {}", buf);

    }

  });

}

} // namespace Http2

} // namespace Http

} // namespace Envoy