Function GetHttpHeader

tools/websocket_to_posix_proxy/src/main.cpp:41–51

Given a multiline string of HTTP headers, returns a pointer to the beginning of the value of given header inside the string that was passed in.

// Given a multiline string of HTTP headers, returns a pointer to the beginning
// of the value of given header inside the string that was passed in.
static int GetHttpHeader(const char *headers, const char *header, char *out, int maxBytesOut) { // thread-safe, re-entrant
  const char *pos = strstr(headers, header);
  if (!pos) return 0;
  pos += strlen(header);
  const char *end = pos;
  while (*end != '\r' && *end != '\n' && *end != '\0') ++end;
  int numBytesToWrite = MIN((int)(end-pos), maxBytesOut-1);
  memcpy(out, pos, numBytesToWrite);
  out[numBytesToWrite] = '\0';
  return (int)(end-pos);
}

// Sends WebSocket handshake back to the given WebSocket connection.
void SendHandshake(int fd, const char *request) {