int HttpClient::skipResponseHeaders()
{
// Just keep reading until we finish reading the headers or time out
unsigned long timeoutStart = millis();
// Whilst we haven't timed out & haven't reached the end of the headers
while ((!endOfHeadersReached()) &&
( (millis() - timeoutStart) < iHttpResponseTimeout ))
{
if (available())
{
(void)readHeader();
// We read something, reset the timeout counter
timeoutStart = millis();
}
else
{
// We haven't got any data, so let's pause to allow some to
// arrive
delay(kHttpWaitForDataDelay);
}
}
if (endOfHeadersReached())
{
// Success
return HTTP_SUCCESS;
}
else
{
// We must've timed out
return HTTP_ERROR_TIMED_OUT;
}
}
int HttpClient::read()
{
#if 0 // Fails on WiFi because multi-byte read seems to be broken
uint8_t b[1];
int ret = read(b, 1);
if (ret == 1)
{
return b[0];
}
else
{
return -1;
}
#else
int ret = iClient->read();
if (ret >= 0)
{
if (endOfHeadersReached() && iContentLength > 0)
{
// We're outputting the body now and we've seen a Content-Length header
// So keep track of how many bytes are left
iBodyLengthConsumed++;
}
}
return ret;
#endif
}
bool HttpClient::headerAvailable()
{
// clear the currently store header line
iHeaderLine = "";
while (!endOfHeadersReached())
{
// read a byte from the header
int c = readHeader();
if (c == '\r' || c == '\n')
{
if (iHeaderLine.length())
{
// end of the line, all done
break;
}
else
{
// ignore any CR or LF characters
continue;
}
}
// append byte to header line
iHeaderLine += (char)c;
}
return (iHeaderLine.length() > 0);
}
int HttpClient::read()
{
if (iIsChunked && !available())
{
return -1;
}
int ret = iClient->read();
if (ret >= 0)
{
if (endOfHeadersReached() && iContentLength > 0)
{
// We're outputting the body now and we've seen a Content-Length header
// So keep track of how many bytes are left
iBodyLengthConsumed++;
}
if (iState == eReadingBodyChunk)
{
iChunkLength--;
if (iChunkLength == 0)
{
iState = eReadingChunkLength;
}
}
}
return ret;
}
bool HttpClient::endOfBodyReached()
{
if (endOfHeadersReached() && (contentLength() != kNoContentLengthHeader))
{
// We've got to the body and we know how long it will be
return (iBodyLengthConsumed >= contentLength());
}
return false;
}
int HttpClient::contentLength()
{
// skip the response headers, if they haven't been read already
if (!endOfHeadersReached())
{
skipResponseHeaders();
}
return iContentLength;
}
int HttpClient::read(uint8_t *buf, size_t size)
{
int ret =iClient->read(buf, size);
if (endOfHeadersReached() && iContentLength > 0)
{
// We're outputting the body now and we've seen a Content-Length header
// So keep track of how many bytes are left
if (ret >= 0)
{
iBodyLengthConsumed += ret;
}
}
return ret;
}
int HttpClient::readHeader()
{
char c = read();
if (endOfHeadersReached())
{
// We've passed the headers, but rather than return an error, we'll just
// act as a slightly less efficient version of read()
return c;
}
// Whilst reading out the headers to whoever wants them, we'll keep an
// eye out for the "Content-Length" header
switch(iState)
{
case eStatusCodeRead:
// We're at the start of a line, or somewhere in the middle of reading
// the Content-Length prefix
if (*iContentLengthPtr == c)
{
// This character matches, just move along
iContentLengthPtr++;
if (*iContentLengthPtr == '\0')
{
// We've reached the end of the prefix
iState = eReadingContentLength;
// Just in case we get multiple Content-Length headers, this
// will ensure we just get the value of the last one
iContentLength = 0;
}
}
else if ((iContentLengthPtr == kContentLengthPrefix) && (c == '\r'))
{
// We've found a '\r' at the start of a line, so this is probably
// the end of the headers
iState = eLineStartingCRFound;
}
else
{
// This isn't the Content-Length header, skip to the end of the line
iState = eSkipToEndOfHeader;
}
break;
case eReadingContentLength:
if (isdigit(c))
{
iContentLength = iContentLength*10 + (c - '0');
}
else
{
// We've reached the end of the content length
// We could sanity check it here or double-check for "\r\n"
// rather than anything else, but let's be lenient
iState = eSkipToEndOfHeader;
}
break;
case eLineStartingCRFound:
if (c == '\n')
{
iState = eReadingBody;
}
break;
default:
// We're just waiting for the end of the line now
break;
};
if ( (c == '\n') && !endOfHeadersReached() )
{
// We've got to the end of this line, start processing again
iState = eStatusCodeRead;
iContentLengthPtr = kContentLengthPrefix;
}
// And return the character read to whoever wants it
return c;
}