image_to_http.cpp

#define HEADER_BUF_SZ   256
char headerBuf[HEADER_BUF_SZ];

char controlName[] = "imgupload";
char fileName[] = "finger.bmpp";

uint16_t connectAndAssembleMultipartHeaders(void)
{
    uint16_t bodyLen = 0;
    
    if (client.connect(server, port)) 
    {
        Serial.println("Connected to server");
        client.println("POST /post HTTP/1.1");
        client.println("Host: 192.168.1.106");
        client.println("Content-Type: multipart/form-data; boundary=X-ARDUINO_MULTIPART");
        client.println("Connection: close");
        
        /* Copy boundary and content disposition for the part */
        uint16_t availSpace = HEADER_BUF_SZ;
        int wouldCopy = 0;
        wouldCopy = snprintf(headerBuf + wouldCopy, availSpace, "--X-ARDUINO_MULTIPART\r\nContent-Disposition: form-data;"
                                                        " name=\"%s\"; filename=\"%s\"\r\n", controlName, fileName);
        
        if (wouldCopy < 0 || wouldCopy >= availSpace)
        {
            Serial.println("Header buffer too small. Stopping.");
            return 0;
        }
        
        bodyLen += wouldCopy;
        availSpace -= wouldCopy;

        /* Copy content type for the part */
        wouldCopy = snprintf(headerBuf + wouldCopy, availSpace, "Content-Type: application/octet-stream\r\n\r\n");
        
        if (wouldCopy < 0 || wouldCopy >= availSpace)
        {
            Serial.println("Header buffer too small (2). Stopping.");
            return 0;
        }
        
        bodyLen += wouldCopy;
        availSpace -= wouldCopy;
        
        /* Add the image size itself */
        uint16_t IMAGE_SZ = 36864;
        bodyLen += IMAGE_SZ;

        /* Add the length of the final boundary */
        bodyLen += strlen("\r\n--X-ARDUINO_MULTIPART--\r\n\r\n");
        
        /* Send content length finally -- a sum of all bytes sent from the beginning of first boundary
         * till the last byte of the last boundary */
        client.print("Content-Length: "); client.print(bodyLen); client.print("\r\n\r\n");
        
        /* Then send the header for the first (and only) part of this multipart request */
        client.print(headerBuf);
        
        return bodyLen;
    }
    
    return 0;
}

void GetFingerprint(){
  if (!set_packet_len_128()) {
    Serial.println("Could not set packet length");
    return;
  }

  delay(100);
    
  int16_t p = -1;
  Serial.println("Waiting for a finger...");
  while (p != FPM_OK) {
    p = finger.getImage();
    switch (p) {
      case FPM_OK:
        Serial.println("Image taken");
        break;
      case FPM_NOFINGER:
        break;
      case FPM_PACKETRECIEVEERR:
        Serial.println("Communication error");
        break;
      case FPM_IMAGEFAIL:
        Serial.println("Imaging error");
        break;
      default:
        Serial.println("Unknown error");
        break;
    }
    yield();
  }
  
  if (connectAndAssembleMultipartHeaders())
  {
      /* The client is ready to send the data. Now request the image from the sensor */
      p = finger.downImage();
      switch (p) {
      case FPM_OK:
        Serial.println("Starting image stream...");
        break;
      case FPM_PACKETRECIEVEERR:
        Serial.println("Communication error");
        return;
      case FPM_UPLOADFAIL:
        Serial.println("Cannot transfer the image");
        return;
      }

      bool read_finished;
      uint16_t readlen = TRANSFER_SZ;
      uint16_t count = 0;
      
      while(true)
      {
        bool ret = finger.readRaw(FPM_OUTPUT_TO_BUFFER, buffer, &read_finished, &readlen);
        if (ret) {
          
          count++;

          client.write(buffer, readlen);
          
          /* indicate the length to be read next time like before */
          readlen = TRANSFER_SZ;
          if (read_finished)
          {
              client.print("\r\n--X-ARDUINO_MULTIPART--\r\n\r\n");
              break;
          }

        }
      }
  }

  while(client.connected()) {
    while(client.available()){
      char c = client.read();
      Serial.print(c);
    }
  }
}