zoneminder/src/zm_remote_camera_http.cpp

//
// ZoneMinder Remote Camera Class Implementation, $Date$, $Revision$
// Copyright (C) 2001-2008 Philip Coombes
// 
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
// 

#include "zm_remote_camera_http.h"

#include "zm_monitor.h"
#include "zm_packet.h"
#include "zm_signal.h"
#include "zm_regexp.h"
#include "zm_utils.h"
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/socket.h>
#include <unistd.h>

#ifdef SOLARIS
#include <sys/filio.h> // FIONREAD and friends
#endif
#ifdef __FreeBSD__
#include <netinet/in.h>
#endif

#if HAVE_LIBPCRE
static RegExpr *header_expr = nullptr;
static RegExpr *status_expr = nullptr;
static RegExpr *connection_expr = nullptr;
static RegExpr *content_length_expr = nullptr;
static RegExpr *content_type_expr = nullptr;
#endif

RemoteCameraHttp::RemoteCameraHttp(
  const Monitor *monitor,
  const std::string &p_method,
  const std::string &p_host,
  const std::string &p_port,
  const std::string &p_path,
  int p_width, int p_height,
  int p_colours,
  int p_brightness,
  int p_contrast,
  int p_hue,
  int p_colour,
  bool p_capture,
  bool p_record_audio ) :
  RemoteCamera(
    monitor,
    "http",
    p_host,
    p_port,
    p_path,
    p_width,
    p_height,
    p_colours,
    p_brightness,
    p_contrast,
    p_hue,
    p_colour,
    p_capture,
    p_record_audio )
{
  sd = -1;

  timeout.tv_sec = 0;
  timeout.tv_usec = 0;

  if ( p_method == "simple" )
    method = SIMPLE;
  else if ( p_method == "regexp" ) {
    method = REGEXP;
  } else
    Fatal("Unrecognised method '%s' when creating HTTP camera %d", p_method.c_str(), monitor->Id());
  if ( capture ) {
    Initialise();
  }
  mVideoStream = nullptr;
}

RemoteCameraHttp::~RemoteCameraHttp() {
  if ( capture ) {
    Terminate();
  }
}

void RemoteCameraHttp::Initialise() {
  RemoteCamera::Initialise();

  if ( request.empty() ) {
    request = stringtf( "GET %s HTTP/%s\r\n", path.c_str(), config.http_version );
    request += stringtf( "User-Agent: %s/%s\r\n", config.http_ua, ZM_VERSION );
    request += stringtf( "Host: %s\r\n", host.c_str());
    if ( strcmp( config.http_version, "1.0" ) == 0 )
      request += "Connection: Keep-Alive\r\n";
    if ( !auth.empty() )
      request += stringtf( "Authorization: Basic %s\r\n", auth64.c_str() );
    request += "\r\n";
    Debug( 2, "Request: %s", request.c_str() );
  }

  if ( !timeout.tv_sec ) {
    timeout.tv_sec = config.http_timeout/1000; 
    timeout.tv_usec = (config.http_timeout%1000)*1000;
  }

  int max_size = width*height*colours;

  buffer.size( max_size );

  mode = SINGLE_IMAGE;
  format = UNDEF;
  state = HEADER;

#if HAVE_LIBPCRE
    if ( method == REGEXP ) {
			if ( !header_expr )
				header_expr = new RegExpr("^(.+?\r?\n\r?\n)", PCRE_DOTALL);
			if ( !status_expr )
				status_expr = new RegExpr("^HTTP/(1\\.[01]) +([0-9]+) +(.+?)\r?\n", PCRE_CASELESS);
			if ( !connection_expr )
				connection_expr = new RegExpr("Connection: ?(.+?)\r?\n", PCRE_CASELESS);
			if ( !content_length_expr )
				content_length_expr = new RegExpr("Content-length: ?([0-9]+)\r?\n", PCRE_CASELESS);
			if ( !content_type_expr )
				content_type_expr = new RegExpr("Content-type: ?(.+?)(?:; ?boundary=\x22?(.+?)\x22?)?\r?\n", PCRE_CASELESS);
		}
#endif
} // end void RemoteCameraHttp::Initialise()

int RemoteCameraHttp::Connect() {
  struct addrinfo *p = nullptr;

  for ( p = hp; p != nullptr; p = p->ai_next ) {
    sd = socket( p->ai_family, p->ai_socktype, p->ai_protocol );
    if ( sd < 0 ) {
      Warning("Can't create socket: %s", strerror(errno) );
      continue;
    }

    if ( connect( sd, p->ai_addr, p->ai_addrlen ) < 0 ) {
      close(sd);
      sd = -1;
      char buf[sizeof(struct in6_addr)];
      struct sockaddr_in *addr;
      addr = (struct sockaddr_in *)p->ai_addr; 
      inet_ntop( AF_INET, &(addr->sin_addr), buf, INET6_ADDRSTRLEN );

      Warning("Can't connect to remote camera mid: %d at %s: %s", monitor->Id(), buf, strerror(errno));
      continue;
    }

    /* If we got here, we must have connected successfully */
    break;
  }

  if ( p == nullptr ) {
    Error("Unable to connect to the remote camera, aborting");
    return -1;
  }

  Debug(3, "Connected to host, socket = %d", sd);
  return sd;
} // end int RemoteCameraHttp::Connect()

int RemoteCameraHttp::Disconnect() {
  close(sd);
  sd = -1;
  Debug(3, "Disconnected from host");
  return 0;
}

int RemoteCameraHttp::SendRequest() {
  Debug(2, "Sending request: %s", request.c_str());
  if ( write(sd, request.data(), request.length()) < 0 ) {
    Error("Can't write: %s", strerror(errno));
    Disconnect();
    return -1;
  }
  format = UNDEF;
  state = HEADER;
  Debug(3, "Request sent");
  return 0;
}

/* Return codes are as follows:
 * -1 means there was an error
 * 0 means no bytes were returned but there wasn't actually an error.
 * > 0 is the # of bytes read.
 */

int RemoteCameraHttp::ReadData(Buffer &buffer, unsigned int bytes_expected) {
  fd_set rfds;
  FD_ZERO(&rfds);
  FD_SET(sd, &rfds);

  struct timeval temp_timeout = timeout;

  int n_found = select(sd+1, &rfds, nullptr, nullptr, &temp_timeout);
  if (n_found == 0) {
    Debug(1, "Select timed out timeout was %d secs %d usecs", temp_timeout.tv_sec, temp_timeout.tv_usec);
    int error = 0;
    socklen_t len = sizeof(error);
    int retval = getsockopt(sd, SOL_SOCKET, SO_ERROR, &error, &len);
    if (retval != 0) {
      Debug(1, "error getting socket error code %s", strerror(retval));
    }
    if (error != 0) {
      return -1;
    }
    // Why are we disconnecting?  It's just a timeout, meaning that data wasn't available.
    //Disconnect();
    return 0;
  } else if (n_found < 0) {
    Error("Select error: %s", strerror(errno));
    return -1;
  }

  unsigned int total_bytes_to_read = 0;

  if (bytes_expected) {
    total_bytes_to_read = bytes_expected;
  } else {
    if (ioctl(sd, FIONREAD, &total_bytes_to_read) < 0) {
      Error("Can't ioctl(): %s", strerror(errno) );
      return -1;
    }

    if (total_bytes_to_read == 0) {
      if (mode == SINGLE_IMAGE) {
        int error = 0;
        socklen_t len = sizeof(error);
        int retval = getsockopt(sd, SOL_SOCKET, SO_ERROR, &error, &len);
        if (retval != 0) {
          Debug(1, "error getting socket error code %s", strerror(retval));
        }
        if (error != 0) {
          return -1;
        }
        // Case where we are grabbing a single jpg, but no content-length was given, so the expectation is that we read until close.
		    return 0;
      }
      // If socket is closed locally, then select will fail, but if it is closed remotely
      // then we have an exception on our socket.. but no data.
      Debug(3, "Socket closed remotely");
      //Disconnect(); // Disconnect is done outside of ReadData now.
      return -1;
    }

    // There can be lots of bytes available.  I've seen 4MB or more. This will vastly inflate our buffer size unnecessarily.
    if (total_bytes_to_read > ZM_NETWORK_BUFSIZ) {
      total_bytes_to_read = ZM_NETWORK_BUFSIZ;
      Debug(4, "Just getting 32K");
    } else {
      Debug(4, "Just getting %d", total_bytes_to_read);
    }
  } // end if bytes_expected or not
  Debug(4, "Expecting %d bytes", total_bytes_to_read);

  int total_bytes_read = 0;
  do {
    int bytes_read = buffer.read_into(sd, total_bytes_to_read);
    if (bytes_read < 0) {
      Error("Read error: %s", strerror(errno));
      return -1;
    } else if (bytes_read == 0) {
      Debug(2, "Socket closed");
      //Disconnect(); // Disconnect is done outside of ReadData now.
      return -1;
    } else if ((unsigned int)bytes_read < total_bytes_to_read) {
      Debug(1, "Incomplete read, expected %d, got %d", total_bytes_to_read, bytes_read);
    } else {
      Debug(3, "Read %d bytes", bytes_read);
    }
    total_bytes_read += bytes_read;
    total_bytes_to_read -= bytes_read;
  } while (total_bytes_to_read);

  Debug(4, "buffer size: %d", static_cast<int>(buffer));

  return total_bytes_read;
}  // end readData

int RemoteCameraHttp::GetData() {
	time_t start_time = time(nullptr);
	int buffer_len = 0;
	while ( !( buffer_len = ReadData(buffer) ) ) {
			if ( zm_terminate ||  ( start_time - time(nullptr) < ZM_WATCH_MAX_DELAY ))
				return -1;
		Debug(4, "Timeout waiting for REGEXP HEADER");
		usleep(100000);
	}
	return buffer_len;
}

int RemoteCameraHttp::GetResponse() {
  int buffer_len;
#if HAVE_LIBPCRE
  if ( method == REGEXP ) {
    const char *header = nullptr;
    int header_len = 0;
    const char *http_version = nullptr;
    int status_code = 0;
    const char *status_mesg = nullptr;
    const char *connection_type = "";
    int content_length = 0;
    const char *content_type = "";
    const char *content_boundary = "";
    const char *subheader = nullptr;
    int subheader_len = 0;
    //int subcontent_length = 0;
    //const char *subcontent_type = "";

    while ( !zm_terminate ) {
      switch( state ) {
        case HEADER :
          {
						buffer_len = GetData();
            if ( buffer_len < 0 ) {
              Error("Unable to read header data");
              return -1;
            }
						bytes += buffer_len;
            if ( header_expr->Match( (char*)buffer, buffer.size() ) == 2 ) {
              header = header_expr->MatchString( 1 );
              header_len = header_expr->MatchLength( 1 );
              Debug(4, "Captured header (%d bytes):\n'%s'", header_len, header);

              if ( status_expr->Match( header, header_len ) < 4 ) {
                Error( "Unable to extract HTTP status from header" );
                return( -1 );
              }
              http_version = status_expr->MatchString( 1 );
              status_code = atoi( status_expr->MatchString( 2 ) );
              status_mesg = status_expr->MatchString( 3 );

              if ( status_code == 401 ) {
                if ( mNeedAuth ) {
                  Error( "Failed authentication: " );
                  return( -1 );
                }
                mNeedAuth = true;
                std::string Header = header;

                mAuthenticator->checkAuthResponse(Header);
                if ( mAuthenticator->auth_method() == zm::AUTH_DIGEST ) {
                  Debug( 2, "Need Digest Authentication" );
                  request = stringtf( "GET %s HTTP/%s\r\n", path.c_str(), config.http_version );
                  request += stringtf( "User-Agent: %s/%s\r\n", config.http_ua, ZM_VERSION );
                  request += stringtf( "Host: %s\r\n", host.c_str());
                  if ( strcmp( config.http_version, "1.0" ) == 0 )
                    request += "Connection: Keep-Alive\r\n";
                  request += mAuthenticator->getAuthHeader( "GET", path.c_str() );
                  request += "\r\n";

                  Debug( 2, "New request header: %s", request.c_str() );
                  return( 0 );
                } 

              } else if ( status_code < 200 || status_code > 299 ) {
                Error( "Invalid response status %d: %s\n%s", status_code, status_mesg, (char *)buffer );
                return( -1 );
              }
              Debug( 3, "Got status '%d' (%s), http version %s", status_code, status_mesg, http_version );

              if ( connection_expr->Match( header, header_len ) == 2 ) {
                connection_type = connection_expr->MatchString( 1 );
                Debug( 3, "Got connection '%s'", connection_type );
              }

              if ( content_length_expr->Match( header, header_len ) == 2 ) {
                content_length = atoi( content_length_expr->MatchString( 1 ) );
                Debug( 3, "Got content length '%d'", content_length );
              }

              if ( content_type_expr->Match( header, header_len ) >= 2 ) {
                content_type = content_type_expr->MatchString( 1 );
                Debug( 3, "Got content type '%s'\n", content_type );
                if ( content_type_expr->MatchCount() > 2 ) {
                  content_boundary = content_type_expr->MatchString( 2 );
                  Debug( 3, "Got content boundary '%s'", content_boundary );
                }
              }

              if ( !strcasecmp( content_type, "image/jpeg" ) || !strcasecmp( content_type, "image/jpg" ) ) {
                // Single image
                mode = SINGLE_IMAGE;
                format = JPEG;
                state = CONTENT;
              } else if ( !strcasecmp( content_type, "image/x-rgb" ) ) {
                // Single image
                mode = SINGLE_IMAGE;
                format = X_RGB;
                state = CONTENT;
              } else if ( !strcasecmp( content_type, "image/x-rgbz" ) ) {
                // Single image
                mode = SINGLE_IMAGE;
                format = X_RGBZ;
                state = CONTENT;
              } else if ( !strcasecmp( content_type, "multipart/x-mixed-replace" ) ) {
                // Image stream, so start processing
                if ( !content_boundary[0] ) {
                  Error( "No content boundary found in header '%s'", header );
                  return( -1 );
                }
                mode = MULTI_IMAGE;
                state = SUBHEADER;
              }
              //else if ( !strcasecmp( content_type, "video/mpeg" ) || !strcasecmp( content_type, "video/mpg" ) )
              //{
              //// MPEG stream, coming soon!
              //}
              else {
                Error( "Unrecognised content type '%s'", content_type );
                return( -1 );
              }
              buffer.consume( header_len );
            } else {
              Debug( 3, "Unable to extract header from stream, retrying" );
              //return( -1 );
            }
            break;
          }
        case SUBHEADER :
          {
            static RegExpr *subheader_expr = nullptr;
            static RegExpr *subcontent_length_expr = nullptr;
            static RegExpr *subcontent_type_expr = nullptr;

            if ( !subheader_expr ) {
              char subheader_pattern[256] = "";
              snprintf( subheader_pattern, sizeof(subheader_pattern), "^((?:\r?\n){0,2}?(?:--)?%s\r?\n.+?\r?\n\r?\n)", content_boundary );
              subheader_expr = new RegExpr( subheader_pattern, PCRE_DOTALL );
            }
            if ( subheader_expr->Match( (char *)buffer, (int)buffer ) == 2 ) {
              subheader = subheader_expr->MatchString( 1 );
              subheader_len = subheader_expr->MatchLength( 1 );
              Debug( 4, "Captured subheader (%d bytes):'%s'", subheader_len, subheader );

              if ( !subcontent_length_expr )
                subcontent_length_expr = new RegExpr( "Content-length: ?([0-9]+)\r?\n", PCRE_CASELESS );
              if ( subcontent_length_expr->Match( subheader, subheader_len ) == 2 ) {
                content_length = atoi( subcontent_length_expr->MatchString( 1 ) );
                Debug( 3, "Got subcontent length '%d'", content_length );
              }

              if ( !subcontent_type_expr )
                subcontent_type_expr = new RegExpr( "Content-type: ?(.+?)\r?\n", PCRE_CASELESS );
              if ( subcontent_type_expr->Match( subheader, subheader_len ) == 2 ) {
                content_type = subcontent_type_expr->MatchString( 1 );
                Debug( 3, "Got subcontent type '%s'", content_type );
              }

              buffer.consume( subheader_len );
              state = CONTENT;
            } else {
              Debug( 3, "Unable to extract subheader from stream, retrying" );
							buffer_len = GetData();
              if ( buffer_len < 0 ) {
                Error( "Unable to extract subheader data" );
                return( -1 );
              }
							bytes += buffer_len;
            }
            break;
          }
        case CONTENT :
          {

            // if content_type is something like image/jpeg;size=, this will strip the ;size=
            char * semicolon = strchr( (char *)content_type, ';' );
            if ( semicolon ) {
              *semicolon = '\0';
            }

            if ( !strcasecmp( content_type, "image/jpeg" ) || !strcasecmp( content_type, "image/jpg" ) ) {
              format = JPEG;
            } else if ( !strcasecmp( content_type, "image/x-rgb" ) ) {
              format = X_RGB;
            } else if ( !strcasecmp( content_type, "image/x-rgbz" ) ) {
              format = X_RGBZ;
            } else {
              Error( "Found unsupported content type '%s'", content_type );
              return( -1 );
            }

            if (content_length) {
              while (((long)buffer.size() < content_length ) and !zm_terminate) {
                Debug(3, "Need more data buffer %d < content length %d", buffer.size(), content_length);
								int bytes_read = ReadData(buffer, content_length - buffer.size());

                if (bytes_read < 0) {
                  Error("Unable to read content");
                  return -1;
                }
								bytes += bytes_read;
              }
              Debug(3, "Got end of image by length, content-length = %d", content_length);
            } else {
              while (!content_length) {
								buffer_len = GetData();
                if (buffer_len < 0) {
                  Error("Unable to read content");
                  return -1;
                }
								bytes += buffer_len;
                static RegExpr *content_expr = 0;
                if (mode == MULTI_IMAGE) {
                  if (!content_expr) {
                    char content_pattern[256] = "";
                    snprintf(content_pattern, sizeof(content_pattern), "^(.+?)(?:\r?\n)*(?:--)?%s\r?\n", content_boundary);
                    content_expr = new RegExpr(content_pattern, PCRE_DOTALL);
                  }
                  if (content_expr->Match( buffer, buffer.size()) == 2) {
                    content_length = content_expr->MatchLength( 1 );
                    Debug(3, "Got end of image by pattern, content-length = %d", content_length);
                  }
                }
              }
            }
            if ( mode == SINGLE_IMAGE ) {
              state = HEADER;
              Disconnect();
            } else {
              state = SUBHEADER;
            }
            Debug( 3, "Returning %d (%d) bytes of captured content", content_length, buffer.size() );
            return content_length;
          }
        case HEADERCONT :
        case SUBHEADERCONT :
            // Ignore
            break;
      }
    }
  } else
#endif // HAVE_LIBPCRE
  {
    static const char *http_match = "HTTP/";
    static const char *connection_match = "Connection:";
    static const char *content_length_match = "Content-length:";
    static const char *content_type_match = "Content-type:";
    static const char *boundary_match = "boundary=";
    static const char *authenticate_match = "WWW-Authenticate:";
    static int http_match_len = 0;
    static int connection_match_len = 0;
    static int content_length_match_len = 0;
    static int content_type_match_len = 0;
    static int boundary_match_len = 0;
    static int authenticate_match_len = 0;

    if ( !http_match_len )
      http_match_len = strlen(http_match);
    if ( !connection_match_len )
      connection_match_len = strlen(connection_match);
    if ( !content_length_match_len )
      content_length_match_len = strlen(content_length_match);
    if ( !content_type_match_len )
      content_type_match_len = strlen(content_type_match);
    if ( !boundary_match_len )
      boundary_match_len = strlen(boundary_match);
    if ( !authenticate_match_len )
      authenticate_match_len = strlen(authenticate_match);

    static int n_headers;
    //static char *headers[32];

    static int n_subheaders;
    //static char *subheaders[32];

    static char *http_header;
    static char *connection_header;
    static char *content_length_header;
    static char *content_type_header;
    static char *boundary_header;
    static char *authenticate_header;
    static char subcontent_length_header[33];
    static char subcontent_type_header[65];

    static char http_version[16];
    static char status_code[16];
    static char status_mesg[256];
    static char connection_type[32];
    static int content_length;
    static char content_type[32];
    static char content_boundary[64];
    static int content_boundary_len;

    while ( !zm_terminate ) {
      switch ( state ) {
        case HEADER :
          {
            n_headers = 0;
            http_header = nullptr;
            connection_header = nullptr;
            content_length_header = nullptr;
            content_type_header = nullptr;
            authenticate_header = nullptr;

            http_version[0] = '\0';
            status_code [0]= '\0';
            status_mesg [0]= '\0';
            connection_type [0]= '\0';
            content_length = 0;
            content_type[0] = '\0';
            content_boundary[0] = '\0';
            content_boundary_len = 0;
            [[gnu::fallthrough]];
          }
        case HEADERCONT :
          {
						buffer_len = GetData();
            if (buffer_len < 0) {
              Error("Unable to read header");
              return -1;
            }
						bytes += buffer_len;

            char *crlf = nullptr;
            char *header_ptr = buffer;
            int header_len = buffer.size();
            bool all_headers = false;

            while (true and !zm_terminate) {
              int crlf_len = memspn(header_ptr, "\r\n", header_len);
              if (n_headers) {
                if (
                    (crlf_len == 2 && !strncmp(header_ptr, "\n\n", crlf_len))
                    ||
                    (crlf_len == 4 && !strncmp(header_ptr, "\r\n\r\n", crlf_len))
                    ) {
									Debug(3, "Have double linefeed, done headers");
                  *header_ptr = '\0';
                  header_ptr += crlf_len;
                  header_len -= buffer.consume(header_ptr-(char *)buffer);
                  all_headers = true;
                  break;
                }
              }
              if (crlf_len) {
                if (header_len == crlf_len) {
                  break;
                } else {
                  *header_ptr = '\0';
                  header_ptr += crlf_len;
                  header_len -= buffer.consume(header_ptr-(char *)buffer);
                }
              }

              Debug(6, "%s", header_ptr);
              if ((crlf = mempbrk(header_ptr, "\r\n", header_len))) {
                //headers[n_headers++] = header_ptr;
                n_headers++;

                if (!http_header && (strncasecmp(header_ptr, http_match, http_match_len) == 0)) {
                  http_header = header_ptr+http_match_len;
                  Debug(6, "Got http header '%s'", header_ptr);
                } else if ( !connection_header && (strncasecmp(header_ptr, connection_match, connection_match_len) == 0) ) {
                  connection_header = header_ptr+connection_match_len;
                  Debug(6, "Got connection header '%s'", header_ptr);
                } else if ( !content_length_header && (strncasecmp(header_ptr, content_length_match, content_length_match_len) == 0) ) {
                  content_length_header = header_ptr+content_length_match_len;
                  Debug(6, "Got content length header '%s'", header_ptr);
                } else if ( !authenticate_header && (strncasecmp(header_ptr, authenticate_match, authenticate_match_len) == 0) ) {
                  authenticate_header = header_ptr;
                  Debug(6, "Got authenticate header '%s'", header_ptr);
                } else if ( !content_type_header && (strncasecmp(header_ptr, content_type_match, content_type_match_len) == 0) ) {
                  content_type_header = header_ptr+content_type_match_len;
                  Debug(6, "Got content type header '%s'", header_ptr);
                } else {
                  Debug(6, "Got ignored header '%s'", header_ptr);
                }
                header_ptr = crlf;
                header_len -= buffer.consume(header_ptr-(char *)buffer);
              } else {
                // No end of line found
                break;
              }
            } // end while search for headers

            if (all_headers) {
              char *start_ptr, *end_ptr;

              if (!http_header) {
                Error("Unable to extract HTTP status from header");
                return -1;
              }

              start_ptr = http_header;
              end_ptr = start_ptr+strspn(start_ptr, "10.");

              // FIXME Why are we memsetting every time?  Can we not do it once?
              //memset(http_version, 0, sizeof(http_version));
              strncpy(http_version, start_ptr, end_ptr-start_ptr);

              start_ptr = end_ptr;
              start_ptr += strspn(start_ptr, " ");
              end_ptr = start_ptr+strspn(start_ptr, "0123456789");

              memset(status_code, 0, sizeof(status_code));
              strncpy(status_code, start_ptr, end_ptr-start_ptr);
              int status = atoi(status_code);

              start_ptr = end_ptr;
              start_ptr += strspn(start_ptr, " ");
              strcpy(status_mesg, start_ptr);

              if (status == 401) {
                if (mNeedAuth) {
                  Error("Failed authentication");
                  return -1;
                }
                if (!authenticate_header) {
                  Error("Failed authentication, but don't have an authentication header.");
                  return -1;
                }
                mNeedAuth = true;
                std::string Header = authenticate_header;
                Debug(2, "Checking for digest auth in %s", authenticate_header);

                mAuthenticator->checkAuthResponse(Header);
                if (mAuthenticator->auth_method() == zm::AUTH_DIGEST) {
                  Debug(2, "Need Digest Authentication");
                  request = stringtf("GET %s HTTP/%s\r\n", path.c_str(), config.http_version);
                  request += stringtf("User-Agent: %s/%s\r\n", config.http_ua, ZM_VERSION);
                  request += stringtf("Host: %s\r\n", host.c_str());
                  if ( strcmp(config.http_version, "1.0") == 0 )
                    request += "Connection: Keep-Alive\r\n";
                  request += mAuthenticator->getAuthHeader("GET", path.c_str());
                  request += "\r\n";

                  Debug(2, "New request header: %s", request.c_str());
                  return 0;
                } else {
                  Debug(2, "Need some other kind of Authentication");
                }
              } else if (status < 200 || status > 299) {
                Error("Invalid response status %s: %s", status_code, status_mesg);
                return -1;
              }
              Debug(3, "Got status '%d' (%s), http version %s", status, status_mesg, http_version);

              if (connection_header) {
                memset(connection_type, 0, sizeof(connection_type));
                start_ptr = connection_header + strspn(connection_header, " ");
                // FIXME Should we not use strncpy?
                strcpy(connection_type, start_ptr);
                Debug(3, "Got connection '%s'", connection_type);
              }
              if (content_length_header) {
                start_ptr = content_length_header + strspn(content_length_header, " ");
                content_length = atoi(start_ptr);
                Debug(3, "Got content length '%d'", content_length);
              }
              if (content_type_header) {
                //memset(content_type, 0, sizeof(content_type));
                start_ptr = content_type_header + strspn(content_type_header, " ");
                if ( (end_ptr = strchr(start_ptr, ';')) ) {
                  strncpy(content_type, start_ptr, end_ptr-start_ptr);
                  Debug(3, "Got content type '%s'", content_type);

                  start_ptr = end_ptr + strspn(end_ptr, "; ");

                  if (strncasecmp(start_ptr, boundary_match, boundary_match_len) == 0) {
                    start_ptr += boundary_match_len;
                    start_ptr += strspn(start_ptr, "-");
                    content_boundary_len = sprintf(content_boundary, "--%s", start_ptr);
                    Debug(3, "Got content boundary '%s'", content_boundary);
                  } else {
                    Error("No content boundary found in header '%s'", content_type_header);
                  }
                } else {
                  strcpy(content_type, start_ptr);
                  Debug(3, "Got content type '%s'", content_type);
                }
              } // end if content_type_header

              if (!strcasecmp(content_type, "image/jpeg") || !strcasecmp(content_type, "image/jpg")) {
                // Single image
                mode = SINGLE_IMAGE;
                format = JPEG;
                state = CONTENT;
              } else if (!strcasecmp(content_type, "image/x-rgb")) {
                // Single image
                mode = SINGLE_IMAGE;
                format = X_RGB;
                state = CONTENT;
              } else if (!strcasecmp(content_type, "image/x-rgbz")) {
                // Single image
                mode = SINGLE_IMAGE;
                format = X_RGBZ;
                state = CONTENT;
              } else if (!strcasecmp(content_type, "multipart/x-mixed-replace")) {
                // Image stream, so start processing
                if (!content_boundary[0]) {
                  Error("No content boundary found in header '%s'", content_type_header);
                  return -1;
                }
                mode = MULTI_IMAGE;
                state = SUBHEADER;
              }
              //else if ( !strcasecmp( content_type, "video/mpeg" ) || !strcasecmp( content_type, "video/mpg" ) )
              //{
              //// MPEG stream, coming soon!
              //}
              else {
                Error("Unrecognised content type '%s'", content_type);
                return -1;
              }
            } else {
              Debug(3, "Unable to extract entire header from stream, continuing");
              state = HEADERCONT;
              //return( -1 );
            } // end if all_headers
            break;
          }
        case SUBHEADER :
          {
            n_subheaders = 0;
            boundary_header = 0;
            subcontent_length_header[0] = '\0';
            subcontent_type_header[0] = '\0';
            content_length = 0;
            content_type[0] = '\0';
            [[gnu::fallthrough]];
          }
        case SUBHEADERCONT :
          {
            char *crlf = nullptr;
            char *subheader_ptr = (char *)buffer;
            int subheader_len = buffer.size();
            bool all_headers = false;

            while (true and !zm_terminate) {
              int crlf_len = memspn(subheader_ptr, "\r\n", subheader_len);
              if (n_subheaders) {
                if ( (crlf_len == 2 && !strncmp(subheader_ptr, "\n\n", crlf_len)) || (crlf_len == 4 && !strncmp( subheader_ptr, "\r\n\r\n", crlf_len )) ) {
                  *subheader_ptr = '\0';
                  subheader_ptr += crlf_len;
                  subheader_len -= buffer.consume(subheader_ptr-(char *)buffer);
                  all_headers = true;
                  break;
                }
              }
              if (crlf_len) {
                if (subheader_len == crlf_len) {
                  break;
                } else {
                  *subheader_ptr = '\0';
                  subheader_ptr += crlf_len;
                  subheader_len -= buffer.consume(subheader_ptr-(char *)buffer);
                }
              }

              Debug(6, "%d: %s", subheader_len, subheader_ptr);

              if ( (crlf = mempbrk(subheader_ptr, "\r\n", subheader_len)) ) {
                //subheaders[n_subheaders++] = subheader_ptr;
                n_subheaders++;

                if ( !boundary_header && (strncasecmp(subheader_ptr, content_boundary, content_boundary_len) == 0) ) {
                  boundary_header = subheader_ptr;
                  Debug(4, "Got boundary subheader '%s'", subheader_ptr);
                } else if (
                    !subcontent_length_header[0]
                    &&
                    (strncasecmp(subheader_ptr, content_length_match, content_length_match_len) == 0)
                    ) {
                  strncpy(
                      subcontent_length_header,
                      subheader_ptr+content_length_match_len,
                      sizeof(subcontent_length_header)-1
                      );
                  *(subcontent_length_header+strcspn(subcontent_length_header, "\r\n")) = '\0';
                  Debug(4, "Got content length subheader '%s'", subcontent_length_header);
                } else if ( !subcontent_type_header[0] && (strncasecmp( subheader_ptr, content_type_match, content_type_match_len) == 0) ) {
                  strncpy(
                      subcontent_type_header,
                      subheader_ptr+content_type_match_len,
                      sizeof(subcontent_type_header)-1
                      );
                  *(subcontent_type_header+strcspn(subcontent_type_header, "\r\n")) = '\0';
                  Debug(4, "Got content type subheader '%s'", subcontent_type_header);
                } else {
                  Debug(6, "Got ignored subheader '%s' found", subheader_ptr);
                }
                subheader_ptr = crlf;
                subheader_len -= buffer.consume( subheader_ptr-(char *)buffer );
              } else {
                // No line end found
                break;
              }
            }

            if (all_headers && boundary_header) {
              char *start_ptr/*, *end_ptr*/;

              Debug(3, "Got boundary '%s'", boundary_header);

              if (subcontent_length_header[0]) {
                start_ptr = subcontent_length_header + strspn(subcontent_length_header, " ");
                content_length = atoi(start_ptr);
                Debug(3, "Got subcontent length '%d'", content_length);
              }
              if (subcontent_type_header[0]) {
                //memset(content_type, 0, sizeof(content_type));
                start_ptr = subcontent_type_header + strspn(subcontent_type_header, " ");
                strcpy(content_type, start_ptr);
                Debug(3, "Got subcontent type '%s'", content_type);
              }
              state = CONTENT;
            } else {
              Debug(3, "Unable to extract subheader from stream, retrying");
							buffer_len = GetData();
              if (buffer_len < 0) {
                Error("Unable to read subheader");
                return -1;
              }
							bytes += buffer_len;
              state = SUBHEADERCONT;
            }
            break;
          }
        case CONTENT : {

            // if content_type is something like image/jpeg;size=, this will strip the ;size=
            char * semicolon = strchr( content_type, ';' );
            if ( semicolon ) {
              *semicolon = '\0';
            }

            if (!strcasecmp(content_type, "image/jpeg") || !strcasecmp(content_type, "image/jpg")) {
              format = JPEG;
            } else if (!strcasecmp(content_type, "image/x-rgb")) {
              format = X_RGB;
            } else if (!strcasecmp(content_type, "image/x-rgbz")) {
              format = X_RGBZ;
            } else {
              Error("Found unsupported content type '%s'", content_type);
              return -1;
            }

            // This is an early test for jpeg content, so we can bail early
            if (format == JPEG and buffer.size() >= 2) {
              if (buffer[0] != 0xff or buffer[1] != 0xd8) {
                Error("Found bogus jpeg header '%02x%02x'", buffer[0], buffer[1]);
                return -1;
              }
            }

            if (content_length) {
              while (((long)buffer.size() < content_length) and !zm_terminate) {
								Debug(4, "getting more data");
								int bytes_read = ReadData(buffer, content_length-buffer.size());
                if (bytes_read < 0) {
                  Error("Unable to read content");
                  return -1;
                }
								bytes += bytes_read;
              }
              Debug(3, "Got end of image by length, content-length = %d", content_length);
            } else {
              // Read until we find the end of image or the stream closes.
              while (!content_length && !zm_terminate) {
								Debug(4, "!content_length, ReadData");
                buffer_len = ReadData(buffer);
                if (buffer_len < 0) {
                  Error("Unable to read content");
                  return -1;
                }
								bytes += buffer_len;
                int buffer_size = buffer.size();
                if (buffer_len) {
                  // Got some data

                  if (mode == MULTI_IMAGE) {
                    // Look for the boundary marker, determine content length using it's position
                    if (char *start_ptr = (char *)memstr( (char *)buffer, "\r\n--", buffer_size)) {
                      content_length = start_ptr - (char *)buffer;
                      Debug(2, "Got end of image by pattern (crlf--), content-length = %d", content_length);
                    } else {
                      Debug(2, "Did not find end of image by patten (crlf--) yet, content-length = %d", content_length);
                    }
                  } // end if MULTI_IMAGE
                } else {
                  content_length = buffer_size;
                  Debug(2, "Got end of image by closure, content-length = %d", content_length);
                  if (mode == SINGLE_IMAGE) {
                    char *end_ptr = (char *)buffer+buffer_size;

                    // strip off any last line feeds
                    while (*end_ptr == '\r' || *end_ptr == '\n') {
                      content_length--;
                      end_ptr--;
                    }

                    if (end_ptr != ((char *)buffer+buffer_size)) {
                      Debug(2, "Trimmed end of image, new content-length = %d", content_length);
                    }
                  } // end if SINGLE_IMAGE
                } // end if read some data
              } // end while ! content_length
            } // end if content_length

            if (mode == SINGLE_IMAGE) {
              state = HEADER;
              Disconnect();
            } else {
              state = SUBHEADER;
            }

            if (format == JPEG && buffer.size() >= 2) {
              if (buffer[0] != 0xff || buffer[1] != 0xd8) {
                Error("Found bogus jpeg header '%02x%02x'", buffer[0], buffer[1]);
                return -1;
              }
            }

            Debug(3, "Returning %d bytes, buffer size: (%d) bytes of captured content",
                content_length, buffer.size());
            return content_length;
        } // end case CONTENT
      } // end switch
    }
  }
  return 0;
} // end RemoteCameraHttp::GetResponse

int RemoteCameraHttp::PrimeCapture() {
  if ( sd < 0 ) {
    Connect();
    if ( sd < 0 ) {
      return -1;
    }
    mode = SINGLE_IMAGE;
    buffer.clear();
  }
  getVideoStream();
  return 1;
}

int RemoteCameraHttp::PreCapture() {
  if ( sd < 0 ) {
    Connect();
    if ( sd < 0 ) {
      return -1;
    }
    mode = SINGLE_IMAGE;
    buffer.clear();
  }
  if ( mode == SINGLE_IMAGE ) {
    if ( SendRequest() < 0 ) {
      Error("Unable to send request");
      return -1;
    }
  }
  return 1;
}  // end int RemoteCameraHttp::PreCapture()

int RemoteCameraHttp::Capture(ZMPacket &packet) {
  int content_length = GetResponse();
  if ( content_length == 0 ) {
    Warning("Unable to capture image, retrying");
    return 0;
  }
  if ( content_length < 0 ) {
    Error("Unable to get response, disconnecting");
    return -1;
  }

  if ( !packet.image ) {
    Debug(1, "Allocating image");
    packet.image = new Image(width, height, colours, subpixelorder);
  }
  Image *image = packet.image;
  packet.keyframe = 1;
  packet.codec_type = AVMEDIA_TYPE_VIDEO;
  packet.packet.stream_index = mVideoStreamId;
  packet.stream = mVideoStream;

  switch ( format ) {
    case JPEG :
      if ( !image->DecodeJpeg(buffer.extract(content_length), content_length, colours, subpixelorder) ) {
        Error("Unable to decode jpeg");
        return -1;
      }
      break;
    case X_RGB :
      if ( content_length != (long)image->Size() ) {
        Error("Image length mismatch, expected %d bytes, content length was %d",
            image->Size(), content_length);
        return -1;
      }
      image->Assign(width, height, colours, subpixelorder, buffer.head(), imagesize);
      break;
    case X_RGBZ :
      if ( !image->Unzip( buffer.extract( content_length ), content_length ) ) {
        Error("Unable to unzip RGB image");
        return -1;
      }
      image->Assign(width, height, colours, subpixelorder, buffer.head(), imagesize);
      break;
    default :
      Error("Unexpected image format encountered");
      return -1;
  }
  return 1;
} // end ZmPacket *RmoteCameraHttp::Capture( &image );

int RemoteCameraHttp::PostCapture() {
  return 1;
}