kc3-lang/libxml2/nanohttp.c

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• Hash : 944e5fe8
  Author :
  Date : 2024-10-23T16:46:03
  

  nanohttp: Fix another stdout file descriptor
  

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• nanohttp.c

• /*
   * nanohttp.c: minimalist HTTP GET implementation to fetch external subsets.
   *             focuses on size, streamability, reentrancy and portability
   *
   * This is clearly not a general purpose HTTP implementation
   * If you look for one, check:
   *         http://www.w3.org/Library/
   *
   * See Copyright for the status of this software.
   *
   * daniel@veillard.com
   */
  
  #define IN_LIBXML
  #include "libxml.h"
  
  #ifdef LIBXML_HTTP_ENABLED
  #include <string.h>
  #include <ctype.h>
  #include <stdlib.h>
  #include <errno.h>
  
  #include <fcntl.h>
  
  #ifdef _WIN32
  
  #include <io.h>
  #include <wsockcompat.h>
  #define XML_SOCKLEN_T int
  
  #else /* _WIN32 */
  
  #include <netdb.h>
  #include <netinet/in.h>
  #include <sys/socket.h>
  #include <sys/time.h>
  #include <unistd.h>
  
  #ifdef HAVE_POLL_H
    #include <poll.h>
  #else
    #include <sys/select.h>
  #endif
  
  /* This can be disabled if you don't have getaddrinfo */
  #define SUPPORT_IP6
  #define XML_SOCKLEN_T socklen_t
  
  #endif /* _WIN32 */
  
  #ifdef LIBXML_ZLIB_ENABLED
  #include <zlib.h>
  #endif
  
  #include <libxml/xmlerror.h>
  #include <libxml/xmlmemory.h>
  #include <libxml/parser.h> /* for xmlStr(n)casecmp() */
  #include <libxml/nanohttp.h>
  #include <libxml/uri.h>
  
  #include "private/error.h"
  #include "private/io.h"
  
  /**
   * A couple portability macros
   */
  #ifndef _WINSOCKAPI_
  #define closesocket(s) close(s)
  #define SOCKET int
  #define INVALID_SOCKET (-1)
  #endif
  
  #define GETHOSTBYNAME_ARG_CAST (char *)
  #define SEND_ARG2_CAST (char *)
  
  #define XML_NANO_HTTP_MAX_REDIR	10
  
  #define XML_NANO_HTTP_CHUNK	4096
  
  #define XML_NANO_HTTP_CLOSED	0
  #define XML_NANO_HTTP_WRITE	1
  #define XML_NANO_HTTP_READ	2
  #define XML_NANO_HTTP_NONE	4
  
  #define __xmlIOErr(domain, code, extra) ((void) 0)
  
  typedef struct xmlNanoHTTPCtxt {
      char *protocol;	/* the protocol name */
      char *hostname;	/* the host name */
      int port;		/* the port */
      char *path;		/* the path within the URL */
      char *query;	/* the query string */
      SOCKET fd;		/* the file descriptor for the socket */
      int state;		/* WRITE / READ / CLOSED */
      char *out;		/* buffer sent (zero terminated) */
      char *outptr;	/* index within the buffer sent */
      char *in;		/* the receiving buffer */
      char *content;	/* the start of the content */
      char *inptr;	/* the next byte to read from network */
      char *inrptr;	/* the next byte to give back to the client */
      int inlen;		/* len of the input buffer */
      int last;		/* return code for last operation */
      int returnValue;	/* the protocol return value */
      int version;        /* the protocol version */
      int ContentLength;  /* specified content length from HTTP header */
      char *contentType;	/* the MIME type for the input */
      char *location;	/* the new URL in case of redirect */
      char *authHeader;	/* contents of {WWW,Proxy}-Authenticate header */
      char *encoding;	/* encoding extracted from the contentType */
      char *mimeType;	/* Mime-Type extracted from the contentType */
  #ifdef LIBXML_ZLIB_ENABLED
      z_stream *strm;	/* Zlib stream object */
      int usesGzip;	/* "Content-Encoding: gzip" was detected */
  #endif
  } xmlNanoHTTPCtxt, *xmlNanoHTTPCtxtPtr;
  
  static int initialized = 0;
  static char *proxy = NULL;	 /* the proxy name if any */
  static int proxyPort;	/* the proxy port if any */
  static unsigned int timeout = 60;/* the select() timeout in seconds */
  
  static int xmlNanoHTTPFetchContent( void * ctx, char ** ptr, int * len );
  
  /**
   * xmlHTTPErrMemory:
   * @extra:  extra information
   *
   * Handle an out of memory condition
   */
  static void
  xmlHTTPErrMemory(void)
  {
      xmlRaiseMemoryError(NULL, NULL, NULL, XML_FROM_HTTP, NULL);
  }
  
  /**
   * A portability function
   */
  static int socket_errno(void) {
  #ifdef _WINSOCKAPI_
      int err = WSAGetLastError();
      switch(err) {
          case WSAECONNRESET:
              return(ECONNRESET);
          case WSAEINPROGRESS:
              return(EINPROGRESS);
          case WSAEINTR:
              return(EINTR);
          case WSAESHUTDOWN:
              return(ESHUTDOWN);
          case WSAEWOULDBLOCK:
              return(EWOULDBLOCK);
          default:
              return(err);
      }
  #else
      return(errno);
  #endif
  }
  
  /**
   * xmlNanoHTTPInit:
   *
   * Initialize the HTTP protocol layer.
   * Currently it just checks for proxy information
   */
  
  void
  xmlNanoHTTPInit(void) {
      const char *env;
  #ifdef _WINSOCKAPI_
      WSADATA wsaData;
  #endif
  
      if (initialized)
  	return;
  
  #ifdef _WINSOCKAPI_
      if (WSAStartup(MAKEWORD(1, 1), &wsaData) != 0)
  	return;
  #endif
  
      if (proxy == NULL) {
  	proxyPort = 80;
  	env = getenv("no_proxy");
  	if (env && ((env[0] == '*') && (env[1] == 0)))
  	    goto done;
  	env = getenv("http_proxy");
  	if (env != NULL) {
  	    xmlNanoHTTPScanProxy(env);
  	    goto done;
  	}
  	env = getenv("HTTP_PROXY");
  	if (env != NULL) {
  	    xmlNanoHTTPScanProxy(env);
  	    goto done;
  	}
      }
  done:
      initialized = 1;
  }
  
  /**
   * xmlNanoHTTPCleanup:
   *
   * Cleanup the HTTP protocol layer.
   */
  
  void
  xmlNanoHTTPCleanup(void) {
      if (proxy != NULL) {
  	xmlFree(proxy);
  	proxy = NULL;
      }
  #ifdef _WINSOCKAPI_
      if (initialized)
  	WSACleanup();
  #endif
      initialized = 0;
      return;
  }
  
  /**
   * xmlNanoHTTPScanURL:
   * @ctxt:  an HTTP context
   * @URL:  The URL used to initialize the context
   *
   * (Re)Initialize an HTTP context by parsing the URL and finding
   * the protocol host port and path it indicates.
   */
  
  static void
  xmlNanoHTTPScanURL(xmlNanoHTTPCtxtPtr ctxt, const char *URL) {
      xmlURIPtr uri;
      int len;
  
      /*
       * Clear any existing data from the context
       */
      if (ctxt->protocol != NULL) {
          xmlFree(ctxt->protocol);
  	ctxt->protocol = NULL;
      }
      if (ctxt->hostname != NULL) {
          xmlFree(ctxt->hostname);
  	ctxt->hostname = NULL;
      }
      if (ctxt->path != NULL) {
          xmlFree(ctxt->path);
  	ctxt->path = NULL;
      }
      if (ctxt->query != NULL) {
          xmlFree(ctxt->query);
  	ctxt->query = NULL;
      }
      if (URL == NULL) return;
  
      uri = xmlParseURIRaw(URL, 1);
      if (uri == NULL)
  	return;
  
      if ((uri->scheme == NULL) || (uri->server == NULL)) {
  	xmlFreeURI(uri);
  	return;
      }
  
      ctxt->protocol = xmlMemStrdup(uri->scheme);
      /* special case of IPv6 addresses, the [] need to be removed */
      if ((uri->server != NULL) && (*uri->server == '[')) {
          len = strlen(uri->server);
  	if ((len > 2) && (uri->server[len - 1] == ']')) {
  	    ctxt->hostname = (char *) xmlCharStrndup(uri->server + 1, len -2);
  	} else
  	    ctxt->hostname = xmlMemStrdup(uri->server);
      } else
  	ctxt->hostname = xmlMemStrdup(uri->server);
      if (uri->path != NULL)
  	ctxt->path = xmlMemStrdup(uri->path);
      else
  	ctxt->path = xmlMemStrdup("/");
      if (uri->query != NULL)
  	ctxt->query = xmlMemStrdup(uri->query);
      if (uri->port != 0)
  	ctxt->port = uri->port;
  
      xmlFreeURI(uri);
  }
  
  /**
   * xmlNanoHTTPScanProxy:
   * @URL:  The proxy URL used to initialize the proxy context
   *
   * (Re)Initialize the HTTP Proxy context by parsing the URL and finding
   * the protocol host port it indicates.
   * Should be like http://myproxy/ or http://myproxy:3128/
   * A NULL URL cleans up proxy information.
   */
  
  void
  xmlNanoHTTPScanProxy(const char *URL) {
      xmlURIPtr uri;
  
      if (proxy != NULL) {
          xmlFree(proxy);
  	proxy = NULL;
      }
      proxyPort = 0;
  
      if (URL == NULL) return;
  
      uri = xmlParseURIRaw(URL, 1);
      if ((uri == NULL) || (uri->scheme == NULL) ||
  	(strcmp(uri->scheme, "http")) || (uri->server == NULL)) {
  	__xmlIOErr(XML_FROM_HTTP, XML_HTTP_URL_SYNTAX, "Syntax Error\n");
  	if (uri != NULL)
  	    xmlFreeURI(uri);
  	return;
      }
  
      proxy = xmlMemStrdup(uri->server);
      if (uri->port != 0)
  	proxyPort = uri->port;
  
      xmlFreeURI(uri);
  }
  
  /**
   * xmlNanoHTTPNewCtxt:
   * @URL:  The URL used to initialize the context
   *
   * Allocate and initialize a new HTTP context.
   *
   * Returns an HTTP context or NULL in case of error.
   */
  
  static xmlNanoHTTPCtxtPtr
  xmlNanoHTTPNewCtxt(const char *URL) {
      xmlNanoHTTPCtxtPtr ret;
  
      ret = (xmlNanoHTTPCtxtPtr) xmlMalloc(sizeof(xmlNanoHTTPCtxt));
      if (ret == NULL) {
          xmlHTTPErrMemory();
          return(NULL);
      }
  
      memset(ret, 0, sizeof(xmlNanoHTTPCtxt));
      ret->port = 80;
      ret->returnValue = 0;
      ret->fd = INVALID_SOCKET;
      ret->ContentLength = -1;
  
      xmlNanoHTTPScanURL(ret, URL);
  
      return(ret);
  }
  
  /**
   * xmlNanoHTTPFreeCtxt:
   * @ctxt:  an HTTP context
   *
   * Frees the context after closing the connection.
   */
  
  static void
  xmlNanoHTTPFreeCtxt(xmlNanoHTTPCtxtPtr ctxt) {
      if (ctxt == NULL) return;
      if (ctxt->hostname != NULL) xmlFree(ctxt->hostname);
      if (ctxt->protocol != NULL) xmlFree(ctxt->protocol);
      if (ctxt->path != NULL) xmlFree(ctxt->path);
      if (ctxt->query != NULL) xmlFree(ctxt->query);
      if (ctxt->out != NULL) xmlFree(ctxt->out);
      if (ctxt->in != NULL) xmlFree(ctxt->in);
      if (ctxt->contentType != NULL) xmlFree(ctxt->contentType);
      if (ctxt->encoding != NULL) xmlFree(ctxt->encoding);
      if (ctxt->mimeType != NULL) xmlFree(ctxt->mimeType);
      if (ctxt->location != NULL) xmlFree(ctxt->location);
      if (ctxt->authHeader != NULL) xmlFree(ctxt->authHeader);
  #ifdef LIBXML_ZLIB_ENABLED
      if (ctxt->strm != NULL) {
  	inflateEnd(ctxt->strm);
  	xmlFree(ctxt->strm);
      }
  #endif
  
      ctxt->state = XML_NANO_HTTP_NONE;
      if (ctxt->fd != INVALID_SOCKET) closesocket(ctxt->fd);
      ctxt->fd = INVALID_SOCKET;
      xmlFree(ctxt);
  }
  
  /**
   * xmlNanoHTTPSend:
   * @ctxt:  an HTTP context
   *
   * Send the input needed to initiate the processing on the server side
   * Returns number of bytes sent or -1 on error.
   */
  
  static int
  xmlNanoHTTPSend(xmlNanoHTTPCtxtPtr ctxt, const char *xmt_ptr, int outlen)
  {
      int total_sent = 0;
  #ifdef HAVE_POLL_H
      struct pollfd p;
  #else
      struct timeval tv;
      fd_set wfd;
  #endif
  
      if ((ctxt->state & XML_NANO_HTTP_WRITE) && (xmt_ptr != NULL)) {
          while (total_sent < outlen) {
              int nsent = send(ctxt->fd, SEND_ARG2_CAST (xmt_ptr + total_sent),
                               outlen - total_sent, 0);
  
              if (nsent > 0)
                  total_sent += nsent;
              else if ((nsent == -1) &&
  #if defined(EAGAIN) && EAGAIN != EWOULDBLOCK
                       (socket_errno() != EAGAIN) &&
  #endif
                       (socket_errno() != EWOULDBLOCK)) {
                  __xmlIOErr(XML_FROM_HTTP, 0, "send failed\n");
                  if (total_sent == 0)
                      total_sent = -1;
                  break;
              } else {
                  /*
                   * No data sent
                   * Since non-blocking sockets are used, wait for
                   * socket to be writable or default timeout prior
                   * to retrying.
                   */
  #ifndef HAVE_POLL_H
  #ifndef _WINSOCKAPI_
                  if (ctxt->fd > FD_SETSIZE)
                      return -1;
  #endif
  
                  tv.tv_sec = timeout;
                  tv.tv_usec = 0;
                  FD_ZERO(&wfd);
  #ifdef _MSC_VER
  #pragma warning(push)
  #pragma warning(disable: 4018)
  #endif
                  FD_SET(ctxt->fd, &wfd);
  #ifdef _MSC_VER
  #pragma warning(pop)
  #endif
                  (void) select(ctxt->fd + 1, NULL, &wfd, NULL, &tv);
  #else
                  p.fd = ctxt->fd;
                  p.events = POLLOUT;
                  (void) poll(&p, 1, timeout * 1000);
  #endif /* !HAVE_POLL_H */
              }
          }
      }
  
      return total_sent;
  }
  
  /**
   * xmlNanoHTTPRecv:
   * @ctxt:  an HTTP context
   *
   * Read information coming from the HTTP connection.
   * This is a blocking call (but it blocks in select(), not read()).
   *
   * Returns the number of byte read or -1 in case of error.
   */
  
  static int
  xmlNanoHTTPRecv(xmlNanoHTTPCtxtPtr ctxt)
  {
  #ifdef HAVE_POLL_H
      struct pollfd p;
  #else
      fd_set rfd;
      struct timeval tv;
  #endif
  
  
      while (ctxt->state & XML_NANO_HTTP_READ) {
          if (ctxt->in == NULL) {
              ctxt->in = xmlMalloc(65000);
              if (ctxt->in == NULL) {
                  xmlHTTPErrMemory();
                  ctxt->last = -1;
                  return (-1);
              }
              ctxt->inlen = 65000;
              ctxt->inptr = ctxt->content = ctxt->inrptr = ctxt->in;
          }
          if (ctxt->inrptr > ctxt->in + XML_NANO_HTTP_CHUNK) {
              int delta = ctxt->inrptr - ctxt->in;
              int len = ctxt->inptr - ctxt->inrptr;
  
              memmove(ctxt->in, ctxt->inrptr, len);
              ctxt->inrptr -= delta;
              ctxt->content -= delta;
              ctxt->inptr -= delta;
          }
          if ((ctxt->in + ctxt->inlen) < (ctxt->inptr + XML_NANO_HTTP_CHUNK)) {
              int d_inptr = ctxt->inptr - ctxt->in;
              int d_content = ctxt->content - ctxt->in;
              int d_inrptr = ctxt->inrptr - ctxt->in;
              char *tmp_ptr = ctxt->in;
  
              ctxt->inlen *= 2;
              ctxt->in = (char *) xmlRealloc(tmp_ptr, ctxt->inlen);
              if (ctxt->in == NULL) {
                  xmlHTTPErrMemory();
                  xmlFree(tmp_ptr);
                  ctxt->last = -1;
                  return (-1);
              }
              ctxt->inptr = ctxt->in + d_inptr;
              ctxt->content = ctxt->in + d_content;
              ctxt->inrptr = ctxt->in + d_inrptr;
          }
          ctxt->last = recv(ctxt->fd, ctxt->inptr, XML_NANO_HTTP_CHUNK, 0);
          if (ctxt->last > 0) {
              ctxt->inptr += ctxt->last;
              return (ctxt->last);
          }
          if (ctxt->last == 0) {
              return (0);
          }
          if (ctxt->last == -1) {
              switch (socket_errno()) {
                  case EINPROGRESS:
                  case EWOULDBLOCK:
  #if defined(EAGAIN) && EAGAIN != EWOULDBLOCK
                  case EAGAIN:
  #endif
                      break;
  
                  case ECONNRESET:
                  case ESHUTDOWN:
                      return (0);
  
                  default:
                      __xmlIOErr(XML_FROM_HTTP, 0, "recv failed\n");
                      return (-1);
              }
          }
  #ifdef HAVE_POLL_H
          p.fd = ctxt->fd;
          p.events = POLLIN;
          if ((poll(&p, 1, timeout * 1000) < 1)
  #if defined(EINTR)
              && (errno != EINTR)
  #endif
              )
              return (0);
  #else /* !HAVE_POLL_H */
  #ifndef _WINSOCKAPI_
          if (ctxt->fd > FD_SETSIZE)
              return 0;
  #endif
  
          tv.tv_sec = timeout;
          tv.tv_usec = 0;
          FD_ZERO(&rfd);
  
  #ifdef _MSC_VER
  #pragma warning(push)
  #pragma warning(disable: 4018)
  #endif
  
          FD_SET(ctxt->fd, &rfd);
  
  #ifdef _MSC_VER
  #pragma warning(pop)
  #endif
  
          if ((select(ctxt->fd + 1, &rfd, NULL, NULL, &tv) < 1)
  #if defined(EINTR)
              && (socket_errno() != EINTR)
  #endif
              )
              return (0);
  #endif /* !HAVE_POLL_H */
      }
      return (0);
  }
  
  /**
   * xmlNanoHTTPReadLine:
   * @ctxt:  an HTTP context
   *
   * Read one line in the HTTP server output, usually for extracting
   * the HTTP protocol information from the answer header.
   *
   * Returns a newly allocated string with a copy of the line, or NULL
   *         which indicate the end of the input.
   */
  
  static char *
  xmlNanoHTTPReadLine(xmlNanoHTTPCtxtPtr ctxt) {
      char buf[4096];
      char *bp = buf;
      int	rc;
  
      while (bp - buf < 4095) {
  	if (ctxt->inrptr == ctxt->inptr) {
  	    if ( (rc = xmlNanoHTTPRecv(ctxt)) == 0) {
  		if (bp == buf)
  		    return(NULL);
  		else
  		    *bp = 0;
  		return(xmlMemStrdup(buf));
  	    }
  	    else if ( rc == -1 ) {
  	        return ( NULL );
  	    }
  	}
  	*bp = *ctxt->inrptr++;
  	if (*bp == '\n') {
  	    *bp = 0;
  	    return(xmlMemStrdup(buf));
  	}
  	if (*bp != '\r')
  	    bp++;
      }
      buf[4095] = 0;
      return(xmlMemStrdup(buf));
  }
  
  
  /**
   * xmlNanoHTTPScanAnswer:
   * @ctxt:  an HTTP context
   * @line:  an HTTP header line
   *
   * Try to extract useful information from the server answer.
   * We currently parse and process:
   *  - The HTTP revision/ return code
   *  - The Content-Type, Mime-Type and charset used
   *  - The Location for redirect processing.
   *
   * Returns -1 in case of failure, the file descriptor number otherwise
   */
  
  static void
  xmlNanoHTTPScanAnswer(xmlNanoHTTPCtxtPtr ctxt, const char *line) {
      const char *cur = line;
  
      if (line == NULL) return;
  
      if (!strncmp(line, "HTTP/", 5)) {
          int version = 0;
  	int ret = 0;
  
  	cur += 5;
  	while ((*cur >= '0') && (*cur <= '9')) {
  	    version *= 10;
  	    version += *cur - '0';
  	    cur++;
  	}
  	if (*cur == '.') {
  	    cur++;
  	    if ((*cur >= '0') && (*cur <= '9')) {
  		version *= 10;
  		version += *cur - '0';
  		cur++;
  	    }
  	    while ((*cur >= '0') && (*cur <= '9'))
  		cur++;
  	} else
  	    version *= 10;
  	if ((*cur != ' ') && (*cur != '\t')) return;
  	while ((*cur == ' ') || (*cur == '\t')) cur++;
  	if ((*cur < '0') || (*cur > '9')) return;
  	while ((*cur >= '0') && (*cur <= '9')) {
  	    ret *= 10;
  	    ret += *cur - '0';
  	    cur++;
  	}
  	if ((*cur != 0) && (*cur != ' ') && (*cur != '\t')) return;
  	ctxt->returnValue = ret;
          ctxt->version = version;
      } else if (!xmlStrncasecmp(BAD_CAST line, BAD_CAST"Content-Type:", 13)) {
          const xmlChar *charset, *last, *mime;
          cur += 13;
  	while ((*cur == ' ') || (*cur == '\t')) cur++;
  	if (ctxt->contentType != NULL)
  	    xmlFree(ctxt->contentType);
  	ctxt->contentType = xmlMemStrdup(cur);
  	mime = (const xmlChar *) cur;
  	last = mime;
  	while ((*last != 0) && (*last != ' ') && (*last != '\t') &&
  	       (*last != ';') && (*last != ','))
  	    last++;
  	if (ctxt->mimeType != NULL)
  	    xmlFree(ctxt->mimeType);
  	ctxt->mimeType = (char *) xmlStrndup(mime, last - mime);
  	charset = xmlStrstr(BAD_CAST ctxt->contentType, BAD_CAST "charset=");
  	if (charset != NULL) {
  	    charset += 8;
  	    last = charset;
  	    while ((*last != 0) && (*last != ' ') && (*last != '\t') &&
  	           (*last != ';') && (*last != ','))
  		last++;
  	    if (ctxt->encoding != NULL)
  	        xmlFree(ctxt->encoding);
  	    ctxt->encoding = (char *) xmlStrndup(charset, last - charset);
  	}
      } else if (!xmlStrncasecmp(BAD_CAST line, BAD_CAST"ContentType:", 12)) {
          const xmlChar *charset, *last, *mime;
          cur += 12;
  	if (ctxt->contentType != NULL) return;
  	while ((*cur == ' ') || (*cur == '\t')) cur++;
  	ctxt->contentType = xmlMemStrdup(cur);
  	mime = (const xmlChar *) cur;
  	last = mime;
  	while ((*last != 0) && (*last != ' ') && (*last != '\t') &&
  	       (*last != ';') && (*last != ','))
  	    last++;
  	if (ctxt->mimeType != NULL)
  	    xmlFree(ctxt->mimeType);
  	ctxt->mimeType = (char *) xmlStrndup(mime, last - mime);
  	charset = xmlStrstr(BAD_CAST ctxt->contentType, BAD_CAST "charset=");
  	if (charset != NULL) {
  	    charset += 8;
  	    last = charset;
  	    while ((*last != 0) && (*last != ' ') && (*last != '\t') &&
  	           (*last != ';') && (*last != ','))
  		last++;
  	    if (ctxt->encoding != NULL)
  	        xmlFree(ctxt->encoding);
  	    ctxt->encoding = (char *) xmlStrndup(charset, last - charset);
  	}
      } else if (!xmlStrncasecmp(BAD_CAST line, BAD_CAST"Location:", 9)) {
          cur += 9;
  	while ((*cur == ' ') || (*cur == '\t')) cur++;
  	if (ctxt->location != NULL)
  	    xmlFree(ctxt->location);
  	if (*cur == '/') {
  	    xmlChar *tmp_http = xmlStrdup(BAD_CAST "http://");
  	    xmlChar *tmp_loc =
  	        xmlStrcat(tmp_http, (const xmlChar *) ctxt->hostname);
  	    ctxt->location =
  	        (char *) xmlStrcat (tmp_loc, (const xmlChar *) cur);
  	} else {
  	    ctxt->location = xmlMemStrdup(cur);
  	}
      } else if (!xmlStrncasecmp(BAD_CAST line, BAD_CAST"WWW-Authenticate:", 17)) {
          cur += 17;
  	while ((*cur == ' ') || (*cur == '\t')) cur++;
  	if (ctxt->authHeader != NULL)
  	    xmlFree(ctxt->authHeader);
  	ctxt->authHeader = xmlMemStrdup(cur);
      } else if (!xmlStrncasecmp(BAD_CAST line, BAD_CAST"Proxy-Authenticate:", 19)) {
          cur += 19;
  	while ((*cur == ' ') || (*cur == '\t')) cur++;
  	if (ctxt->authHeader != NULL)
  	    xmlFree(ctxt->authHeader);
  	ctxt->authHeader = xmlMemStrdup(cur);
  #ifdef LIBXML_ZLIB_ENABLED
      } else if ( !xmlStrncasecmp( BAD_CAST line, BAD_CAST"Content-Encoding:", 17) ) {
  	cur += 17;
  	while ((*cur == ' ') || (*cur == '\t')) cur++;
  	if ( !xmlStrncasecmp( BAD_CAST cur, BAD_CAST"gzip", 4) ) {
  	    ctxt->usesGzip = 1;
  
  	    ctxt->strm = xmlMalloc(sizeof(z_stream));
  
  	    if (ctxt->strm != NULL) {
  		ctxt->strm->zalloc = Z_NULL;
  		ctxt->strm->zfree = Z_NULL;
  		ctxt->strm->opaque = Z_NULL;
  		ctxt->strm->avail_in = 0;
  		ctxt->strm->next_in = Z_NULL;
  
  		inflateInit2( ctxt->strm, 31 );
  	    }
  	}
  #endif
      } else if ( !xmlStrncasecmp( BAD_CAST line, BAD_CAST"Content-Length:", 15) ) {
  	cur += 15;
  	ctxt->ContentLength = strtol( cur, NULL, 10 );
      }
  }
  
  /**
   * xmlNanoHTTPConnectAttempt:
   * @addr:  a socket address structure
   *
   * Attempt a connection to the given IP:port endpoint. It forces
   * non-blocking semantic on the socket, and allow 60 seconds for
   * the host to answer.
   *
   * Returns -1 in case of failure, the file descriptor number otherwise
   */
  
  static SOCKET
  xmlNanoHTTPConnectAttempt(struct sockaddr *addr)
  {
  #ifndef HAVE_POLL_H
      fd_set wfd;
  #ifdef _WINSOCKAPI_
      fd_set xfd;
  #endif
      struct timeval tv;
  #else /* !HAVE_POLL_H */
      struct pollfd p;
  #endif /* !HAVE_POLL_H */
      int status;
  
      int addrlen;
  
      SOCKET s;
  
  #ifdef SUPPORT_IP6
      if (addr->sa_family == AF_INET6) {
          s = socket(PF_INET6, SOCK_STREAM, IPPROTO_TCP);
          addrlen = sizeof(struct sockaddr_in6);
      } else
  #endif
      {
          s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
          addrlen = sizeof(struct sockaddr_in);
      }
      if (s == INVALID_SOCKET) {
          __xmlIOErr(XML_FROM_HTTP, 0, "socket failed\n");
          return INVALID_SOCKET;
      }
  #ifdef _WINSOCKAPI_
      {
          u_long one = 1;
  
          status = ioctlsocket(s, FIONBIO, &one) == SOCKET_ERROR ? -1 : 0;
      }
  #else /* _WINSOCKAPI_ */
  #if defined(VMS)
      {
          int enable = 1;
  
          status = ioctl(s, FIONBIO, &enable);
      }
  #else /* VMS */
      if ((status = fcntl(s, F_GETFL, 0)) != -1) {
  #ifdef O_NONBLOCK
          status |= O_NONBLOCK;
  #else /* O_NONBLOCK */
  #ifdef F_NDELAY
          status |= F_NDELAY;
  #endif /* F_NDELAY */
  #endif /* !O_NONBLOCK */
          status = fcntl(s, F_SETFL, status);
      }
      if (status < 0) {
          __xmlIOErr(XML_FROM_HTTP, 0, "error setting non-blocking IO\n");
          closesocket(s);
          return INVALID_SOCKET;
      }
  #endif /* !VMS */
  #endif /* !_WINSOCKAPI_ */
  
      if (connect(s, addr, addrlen) == -1) {
          switch (socket_errno()) {
              case EINPROGRESS:
              case EWOULDBLOCK:
                  break;
              default:
                  __xmlIOErr(XML_FROM_HTTP, 0,
                             "error connecting to HTTP server");
                  closesocket(s);
                  return INVALID_SOCKET;
          }
      }
  #ifndef HAVE_POLL_H
      tv.tv_sec = timeout;
      tv.tv_usec = 0;
  
  #ifdef _MSC_VER
  #pragma warning(push)
  #pragma warning(disable: 4018)
  #endif
  #ifndef _WINSOCKAPI_
      if (s > FD_SETSIZE)
          return INVALID_SOCKET;
  #endif
      FD_ZERO(&wfd);
      FD_SET(s, &wfd);
  
  #ifdef _WINSOCKAPI_
      FD_ZERO(&xfd);
      FD_SET(s, &xfd);
  
      switch (select(s + 1, NULL, &wfd, &xfd, &tv))
  #else
      switch (select(s + 1, NULL, &wfd, NULL, &tv))
  #endif
  #ifdef _MSC_VER
  #pragma warning(pop)
  #endif
  
  #else /* !HAVE_POLL_H */
      p.fd = s;
      p.events = POLLOUT;
      switch (poll(&p, 1, timeout * 1000))
  #endif /* !HAVE_POLL_H */
  
      {
          case 0:
              /* Time out */
              __xmlIOErr(XML_FROM_HTTP, 0, "Connect attempt timed out");
              closesocket(s);
              return INVALID_SOCKET;
          case -1:
              /* Ermm.. ?? */
              __xmlIOErr(XML_FROM_HTTP, 0, "Connect failed");
              closesocket(s);
              return INVALID_SOCKET;
      }
  
  #ifndef HAVE_POLL_H
      if (FD_ISSET(s, &wfd)
  #ifdef _WINSOCKAPI_
          || FD_ISSET(s, &xfd)
  #endif
          )
  #else /* !HAVE_POLL_H */
      if (p.revents == POLLOUT)
  #endif /* !HAVE_POLL_H */
      {
          XML_SOCKLEN_T len;
  
          len = sizeof(status);
  #ifdef SO_ERROR
          if (getsockopt(s, SOL_SOCKET, SO_ERROR, (char *) &status, &len) <
              0) {
              /* Solaris error code */
              __xmlIOErr(XML_FROM_HTTP, 0, "getsockopt failed\n");
              closesocket(s);
              return INVALID_SOCKET;
          }
  #endif
          if (status) {
              __xmlIOErr(XML_FROM_HTTP, 0,
                         "Error connecting to remote host");
              closesocket(s);
              errno = status;
              return INVALID_SOCKET;
          }
      } else {
          /* pbm */
          __xmlIOErr(XML_FROM_HTTP, 0, "select failed\n");
          closesocket(s);
          return INVALID_SOCKET;
      }
  
      return (s);
  }
  
  /**
   * xmlNanoHTTPConnectHost:
   * @host:  the host name
   * @port:  the port number
   *
   * Attempt a connection to the given host:port endpoint. It tries
   * the multiple IP provided by the DNS if available.
   *
   * Returns -1 in case of failure, the file descriptor number otherwise
   */
  
  static SOCKET
  xmlNanoHTTPConnectHost(const char *host, int port)
  {
      struct sockaddr *addr = NULL;
      struct sockaddr_in sockin;
  
  #ifdef SUPPORT_IP6
      struct sockaddr_in6 sockin6;
  #endif
      SOCKET s;
  
      memset (&sockin, 0, sizeof(sockin));
  
  #if defined(SUPPORT_IP6)
      {
  	int status;
  	struct addrinfo hints, *res, *result;
  
          memset (&sockin6, 0, sizeof(sockin6));
  
  	result = NULL;
  	memset (&hints, 0,sizeof(hints));
  	hints.ai_socktype = SOCK_STREAM;
  
  	status = getaddrinfo (host, NULL, &hints, &result);
  	if (status) {
  	    __xmlIOErr(XML_FROM_HTTP, 0, "getaddrinfo failed\n");
  	    return INVALID_SOCKET;
  	}
  
  	for (res = result; res; res = res->ai_next) {
  	    if (res->ai_family == AF_INET) {
  		if ((size_t)res->ai_addrlen > sizeof(sockin)) {
  		    __xmlIOErr(XML_FROM_HTTP, 0, "address size mismatch\n");
  		    freeaddrinfo (result);
  		    return INVALID_SOCKET;
  		}
  		memcpy (&sockin, res->ai_addr, res->ai_addrlen);
  		sockin.sin_port = htons (port);
  		addr = (struct sockaddr *)&sockin;
  	    } else if (res->ai_family == AF_INET6) {
  		if ((size_t)res->ai_addrlen > sizeof(sockin6)) {
  		    __xmlIOErr(XML_FROM_HTTP, 0, "address size mismatch\n");
  		    freeaddrinfo (result);
  		    return INVALID_SOCKET;
  		}
  		memcpy (&sockin6, res->ai_addr, res->ai_addrlen);
  		sockin6.sin6_port = htons (port);
  		addr = (struct sockaddr *)&sockin6;
  	    } else
  		continue;              /* for */
  
  	    s = xmlNanoHTTPConnectAttempt (addr);
  	    if (s != INVALID_SOCKET) {
  		freeaddrinfo (result);
  		return (s);
  	    }
  	}
  
  	if (result)
  	    freeaddrinfo (result);
      }
  #else
      {
          struct hostent *h;
          struct in_addr ia;
          int i;
  
  	h = gethostbyname (GETHOSTBYNAME_ARG_CAST host);
  	if (h == NULL) {
  
  /*
   * Okay, I got fed up by the non-portability of this error message
   * extraction code. it work on Linux, if it work on your platform
   * and one want to enable it, send me the defined(foobar) needed
   */
  #if defined(HOST_NOT_FOUND) && defined(__linux__)
  	    const char *h_err_txt = "";
  
  	    switch (h_errno) {
  		case HOST_NOT_FOUND:
  		    h_err_txt = "Authoritative host not found";
  		    break;
  
  		case TRY_AGAIN:
  		    h_err_txt =
  			"Non-authoritative host not found or server failure.";
  		    break;
  
  		case NO_RECOVERY:
  		    h_err_txt =
  			"Non-recoverable errors:  FORMERR, REFUSED, or NOTIMP.";
  		    break;
  
  #ifdef NO_ADDRESS
  		case NO_ADDRESS:
  		    h_err_txt =
  			"Valid name, no data record of requested type.";
  		    break;
  #endif
  
  		default:
  		    h_err_txt = "No error text defined.";
  		    break;
  	    }
  	    __xmlIOErr(XML_FROM_HTTP, 0, h_err_txt);
  #else
  	    __xmlIOErr(XML_FROM_HTTP, 0, "Failed to resolve host");
  #endif
  	    return INVALID_SOCKET;
  	}
  
  	for (i = 0; h->h_addr_list[i]; i++) {
  	    if (h->h_addrtype == AF_INET) {
  		/* A records (IPv4) */
  		if ((unsigned int) h->h_length > sizeof(ia)) {
  		    __xmlIOErr(XML_FROM_HTTP, 0, "address size mismatch\n");
  		    return INVALID_SOCKET;
  		}
  		memcpy (&ia, h->h_addr_list[i], h->h_length);
  		sockin.sin_family = h->h_addrtype;
  		sockin.sin_addr = ia;
  		sockin.sin_port = (unsigned short)htons ((unsigned short)port);
  		addr = (struct sockaddr *) &sockin;
  	    } else
  		break;              /* for */
  
  	    s = xmlNanoHTTPConnectAttempt (addr);
  	    if (s != INVALID_SOCKET)
  		return (s);
  	}
      }
  #endif
  
      return INVALID_SOCKET;
  }
  
  
  /**
   * xmlNanoHTTPOpen:
   * @URL:  The URL to load
   * @contentType:  if available the Content-Type information will be
   *                returned at that location
   *
   * This function try to open a connection to the indicated resource
   * via HTTP GET.
   *
   * Returns NULL in case of failure, otherwise a request handler.
   *     The contentType, if provided must be freed by the caller
   */
  
  void*
  xmlNanoHTTPOpen(const char *URL, char **contentType) {
      if (contentType != NULL) *contentType = NULL;
      return(xmlNanoHTTPMethod(URL, NULL, NULL, contentType, NULL, 0));
  }
  
  /**
   * xmlNanoHTTPOpenRedir:
   * @URL:  The URL to load
   * @contentType:  if available the Content-Type information will be
   *                returned at that location
   * @redir: if available the redirected URL will be returned
   *
   * This function try to open a connection to the indicated resource
   * via HTTP GET.
   *
   * Returns NULL in case of failure, otherwise a request handler.
   *     The contentType, if provided must be freed by the caller
   */
  
  void*
  xmlNanoHTTPOpenRedir(const char *URL, char **contentType, char **redir) {
      if (contentType != NULL) *contentType = NULL;
      if (redir != NULL) *redir = NULL;
      return(xmlNanoHTTPMethodRedir(URL, NULL, NULL, contentType, redir, NULL,0));
  }
  
  /**
   * xmlNanoHTTPRead:
   * @ctx:  the HTTP context
   * @dest:  a buffer
   * @len:  the buffer length
   *
   * This function tries to read @len bytes from the existing HTTP connection
   * and saves them in @dest. This is a blocking call.
   *
   * Returns the number of byte read. 0 is an indication of an end of connection.
   *         -1 indicates a parameter error.
   */
  int
  xmlNanoHTTPRead(void *ctx, void *dest, int len) {
      xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;
  #ifdef LIBXML_ZLIB_ENABLED
      int bytes_read = 0;
      int orig_avail_in;
      int z_ret;
  #endif
  
      if (ctx == NULL) return(-1);
      if (dest == NULL) return(-1);
      if (len <= 0) return(0);
  
  #ifdef LIBXML_ZLIB_ENABLED
      if (ctxt->usesGzip == 1) {
          if (ctxt->strm == NULL) return(0);
  
          ctxt->strm->next_out = dest;
          ctxt->strm->avail_out = len;
  	ctxt->strm->avail_in = ctxt->inptr - ctxt->inrptr;
  
          while (ctxt->strm->avail_out > 0 &&
  	       (ctxt->strm->avail_in > 0 || xmlNanoHTTPRecv(ctxt) > 0)) {
              orig_avail_in = ctxt->strm->avail_in =
  			    ctxt->inptr - ctxt->inrptr - bytes_read;
              ctxt->strm->next_in = BAD_CAST (ctxt->inrptr + bytes_read);
  
              z_ret = inflate(ctxt->strm, Z_NO_FLUSH);
              bytes_read += orig_avail_in - ctxt->strm->avail_in;
  
              if (z_ret != Z_OK) break;
  	}
  
          ctxt->inrptr += bytes_read;
          return(len - ctxt->strm->avail_out);
      }
  #endif
  
      while (ctxt->inptr - ctxt->inrptr < len) {
          if (xmlNanoHTTPRecv(ctxt) <= 0) break;
      }
      if (ctxt->inptr - ctxt->inrptr < len)
          len = ctxt->inptr - ctxt->inrptr;
      if (len > 0) {
          memcpy(dest, ctxt->inrptr, len);
          ctxt->inrptr += len;
      }
      return(len);
  }
  
  /**
   * xmlNanoHTTPClose:
   * @ctx:  the HTTP context
   *
   * This function closes an HTTP context, it ends up the connection and
   * free all data related to it.
   */
  void
  xmlNanoHTTPClose(void *ctx) {
      xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;
  
      if (ctx == NULL) return;
  
      xmlNanoHTTPFreeCtxt(ctxt);
  }
  
  
  /**
   * xmlNanoHTTPHostnameMatch:
   * @pattern: The pattern as it appears in no_proxy environment variable
   * @hostname: The hostname to test as it appears in the URL
   *
   * This function tests whether a given hostname matches a pattern. The pattern
   * usually is a token from the no_proxy environment variable. Wildcards in the
   * pattern are not supported.
   *
   * Returns true, iff hostname matches the pattern.
   */
  
  static int 
  xmlNanoHTTPHostnameMatch(const char *pattern, const char *hostname) {
      int idx_pattern, idx_hostname;
      const char * pattern_start;
  
      if (!pattern || *pattern == '\0' || !hostname)
  	return 0;
  
      /* Ignore trailing '.' */
      if (*pattern == '.') {
          idx_pattern = strlen(pattern) -1;
          pattern_start = pattern + 1;
      }
      else {
          idx_pattern = strlen(pattern);
          pattern_start = pattern;
      }
      idx_hostname = strlen(hostname);
  
      for (; idx_pattern >= 0 && idx_hostname >= 0; 
             --idx_pattern, --idx_hostname) {
  	if (tolower((unsigned char)pattern_start[idx_pattern]) !=
              tolower((unsigned char)hostname[idx_hostname]))
  	    break;
      }
  
      return idx_pattern == -1 && (idx_hostname == -1|| hostname[idx_hostname] == '.');
  }
  
  
  /**
   * xmlNanoHTTPBypassProxy:
   * @hostname: The hostname as it appears in the URL
   *
   * This function evaluates the no_proxy environment variable and returns
   * whether the proxy server should be bypassed for a given host.
   *
   * Returns true, iff a proxy server should be bypassed for the given hostname.
   */
  
  static int
  xmlNanoHTTPBypassProxy(const char *hostname) {
      size_t envlen;
      char *env = getenv("no_proxy"), *cpy=NULL, *p=NULL;
      if (!env)
  	return 0;
  
      /* (Avoid strdup because it's not portable.) */
      envlen = strlen(env) + 1;
      cpy = xmlMalloc(envlen);
      memcpy(cpy, env, envlen);
      env = cpy;
  
      /* The remainder of the function is basically a tokenizing: */
      while (isspace((unsigned char)*env))
      	++env;
      if (*env == '\0') {
      	xmlFree(cpy);
  	return 0;
      }
  
      p = env;
      while (*env) {
  
      	if (*env != ',') {
  	    ++env;
  	    continue;
  	}
  
  	*(env++) = '\0';
  	if (xmlNanoHTTPHostnameMatch(p, hostname)) {
  	    xmlFree(cpy);
  	    return 1;
  	}
  
  	while (isspace((unsigned char)*env))
  	    ++env;
  	p = env;
      }
      if (xmlNanoHTTPHostnameMatch(p, hostname)) {
      	xmlFree(cpy);
      	return 1;
      }
  
      xmlFree(cpy);
      return 0;
  }
  
  
  /**
   * xmlNanoHTTPMethodRedir:
   * @URL:  The URL to load
   * @method:  the HTTP method to use
   * @input:  the input string if any
   * @contentType:  the Content-Type information IN and OUT
   * @redir:  the redirected URL OUT
   * @headers:  the extra headers
   * @ilen:  input length
   *
   * This function try to open a connection to the indicated resource
   * via HTTP using the given @method, adding the given extra headers
   * and the input buffer for the request content.
   *
   * Returns NULL in case of failure, otherwise a request handler.
   *     The contentType, or redir, if provided must be freed by the caller
   */
  
  void*
  xmlNanoHTTPMethodRedir(const char *URL, const char *method, const char *input,
                    char **contentType, char **redir,
  		  const char *headers, int ilen ) {
      xmlNanoHTTPCtxtPtr ctxt;
      char *bp, *p;
      int blen;
      SOCKET ret;
      int nbRedirects = 0;
      int use_proxy;
      char *redirURL = NULL;
  
      if (URL == NULL) return(NULL);
      if (method == NULL) method = "GET";
      xmlNanoHTTPInit();
  
  retry:
      if (redirURL == NULL) {
  	ctxt = xmlNanoHTTPNewCtxt(URL);
  	if (ctxt == NULL)
  	    return(NULL);
      } else {
  	ctxt = xmlNanoHTTPNewCtxt(redirURL);
  	if (ctxt == NULL)
  	    return(NULL);
  	ctxt->location = xmlMemStrdup(redirURL);
      }
  
      if ((ctxt->protocol == NULL) || (strcmp(ctxt->protocol, "http"))) {
  	__xmlIOErr(XML_FROM_IO, XML_IO_UNSUPPORTED_PROTOCOL, ctxt->protocol);
          xmlNanoHTTPFreeCtxt(ctxt);
  	if (redirURL != NULL) xmlFree(redirURL);
          return(NULL);
      }
      if (ctxt->hostname == NULL) {
  	__xmlIOErr(XML_FROM_HTTP, XML_HTTP_UNKNOWN_HOST,
  	           "Failed to identify host in URI");
          xmlNanoHTTPFreeCtxt(ctxt);
  	if (redirURL != NULL) xmlFree(redirURL);
          return(NULL);
      }
      use_proxy = proxy && !xmlNanoHTTPBypassProxy(ctxt->hostname);
      if (use_proxy) {
  	blen = strlen(ctxt->hostname) * 2 + 16;
  	ret = xmlNanoHTTPConnectHost(proxy, proxyPort);
      }
      else {
  	blen = strlen(ctxt->hostname);
  	ret = xmlNanoHTTPConnectHost(ctxt->hostname, ctxt->port);
      }
      if (ret == INVALID_SOCKET) {
          xmlNanoHTTPFreeCtxt(ctxt);
  	if (redirURL != NULL) xmlFree(redirURL);
          return(NULL);
      }
      ctxt->fd = ret;
  
      if (input == NULL)
  	ilen = 0;
      else
  	blen += 36;
  
      if (headers != NULL)
  	blen += strlen(headers) + 2;
      if (contentType && *contentType)
  	/* reserve for string plus 'Content-Type: \r\n" */
  	blen += strlen(*contentType) + 16;
      if (ctxt->query != NULL)
  	/* 1 for '?' */
  	blen += strlen(ctxt->query) + 1;
      blen += strlen(method) + strlen(ctxt->path) + 24;
  #ifdef LIBXML_ZLIB_ENABLED
      /* reserve for possible 'Accept-Encoding: gzip' string */
      blen += 23;
  #endif
      if (ctxt->port != 80) {
  	/* reserve space for ':xxxxx', incl. potential proxy */
  	if (use_proxy)
  	    blen += 17;
  	else
  	    blen += 11;
      }
      bp = xmlMalloc(blen);
      if ( bp == NULL ) {
          xmlNanoHTTPFreeCtxt( ctxt );
  	xmlHTTPErrMemory();
  	return ( NULL );
      }
  
      p = bp;
  
      if (use_proxy) {
  	if (ctxt->port != 80) {
  	    p += snprintf( p, blen - (p - bp), "%s http://%s:%d%s",
  			method, ctxt->hostname,
  			ctxt->port, ctxt->path );
  	}
  	else
  	    p += snprintf( p, blen - (p - bp), "%s http://%s%s", method,
  			ctxt->hostname, ctxt->path);
      }
      else
  	p += snprintf( p, blen - (p - bp), "%s %s", method, ctxt->path);
  
      if (ctxt->query != NULL)
  	p += snprintf( p, blen - (p - bp), "?%s", ctxt->query);
  
      if (ctxt->port == 80) {
          p += snprintf( p, blen - (p - bp), " HTTP/1.0\r\nHost: %s\r\n",
  		    ctxt->hostname);
      } else {
          p += snprintf( p, blen - (p - bp), " HTTP/1.0\r\nHost: %s:%d\r\n",
  		    ctxt->hostname, ctxt->port);
      }
  
  #ifdef LIBXML_ZLIB_ENABLED
      p += snprintf(p, blen - (p - bp), "Accept-Encoding: gzip\r\n");
  #endif
  
      if (contentType != NULL && *contentType)
  	p += snprintf(p, blen - (p - bp), "Content-Type: %s\r\n", *contentType);
  
      if (headers != NULL)
  	p += snprintf( p, blen - (p - bp), "%s", headers );
  
      if (input != NULL)
  	snprintf(p, blen - (p - bp), "Content-Length: %d\r\n\r\n", ilen );
      else
  	snprintf(p, blen - (p - bp), "\r\n");
  
      ctxt->outptr = ctxt->out = bp;
      ctxt->state = XML_NANO_HTTP_WRITE;
      blen = strlen( ctxt->out );
      xmlNanoHTTPSend(ctxt, ctxt->out, blen );
  
      if ( input != NULL ) {
  	xmlNanoHTTPSend( ctxt, input, ilen );
      }
  
      ctxt->state = XML_NANO_HTTP_READ;
  
      while ((p = xmlNanoHTTPReadLine(ctxt)) != NULL) {
          if (*p == 0) {
  	    ctxt->content = ctxt->inrptr;
  	    xmlFree(p);
  	    break;
  	}
  	xmlNanoHTTPScanAnswer(ctxt, p);
  
          xmlFree(p);
      }
  
      if ((ctxt->location != NULL) && (ctxt->returnValue >= 300) &&
          (ctxt->returnValue < 400)) {
  	while ( xmlNanoHTTPRecv(ctxt) > 0 )
              ;
          if (nbRedirects < XML_NANO_HTTP_MAX_REDIR) {
  	    nbRedirects++;
  	    if (redirURL != NULL)
  		xmlFree(redirURL);
  	    redirURL = xmlMemStrdup(ctxt->location);
  	    xmlNanoHTTPFreeCtxt(ctxt);
  	    goto retry;
  	}
  	xmlNanoHTTPFreeCtxt(ctxt);
  	if (redirURL != NULL) xmlFree(redirURL);
  	return(NULL);
      }
  
      if (contentType != NULL) {
  	if (ctxt->contentType != NULL)
  	    *contentType = xmlMemStrdup(ctxt->contentType);
  	else
  	    *contentType = NULL;
      }
  
      if ((redir != NULL) && (redirURL != NULL)) {
  	*redir = redirURL;
      } else {
  	if (redirURL != NULL)
  	    xmlFree(redirURL);
  	if (redir != NULL)
  	    *redir = NULL;
      }
  
      return((void *) ctxt);
  }
  
  /**
   * xmlNanoHTTPMethod:
   * @URL:  The URL to load
   * @method:  the HTTP method to use
   * @input:  the input string if any
   * @contentType:  the Content-Type information IN and OUT
   * @headers:  the extra headers
   * @ilen:  input length
   *
   * This function try to open a connection to the indicated resource
   * via HTTP using the given @method, adding the given extra headers
   * and the input buffer for the request content.
   *
   * Returns NULL in case of failure, otherwise a request handler.
   *     The contentType, if provided must be freed by the caller
   */
  
  void*
  xmlNanoHTTPMethod(const char *URL, const char *method, const char *input,
                    char **contentType, const char *headers, int ilen) {
      return(xmlNanoHTTPMethodRedir(URL, method, input, contentType,
  		                  NULL, headers, ilen));
  }
  
  /**
   * xmlNanoHTTPFetch:
   * @URL:  The URL to load
   * @filename:  the filename where the content should be saved
   * @contentType:  if available the Content-Type information will be
   *                returned at that location
   *
   * This function try to fetch the indicated resource via HTTP GET
   * and save it's content in the file.
   *
   * Returns -1 in case of failure, 0 in case of success. The contentType,
   *     if provided must be freed by the caller
   */
  int
  xmlNanoHTTPFetch(const char *URL, const char *filename, char **contentType) {
      void *ctxt = NULL;
      char *buf = NULL;
      int fd;
      int len;
      int ret = 0;
  
      if (filename == NULL) return(-1);
      ctxt = xmlNanoHTTPOpen(URL, contentType);
      if (ctxt == NULL) return(-1);
  
      if (!strcmp(filename, "-"))
          fd = 1; /* STDOUT_FILENO */
      else {
          fd = open(filename, O_CREAT | O_WRONLY, 00644);
  	if (fd < 0) {
  	    xmlNanoHTTPClose(ctxt);
  	    if ((contentType != NULL) && (*contentType != NULL)) {
  	        xmlFree(*contentType);
  		*contentType = NULL;
  	    }
  	    return(-1);
  	}
      }
  
      xmlNanoHTTPFetchContent( ctxt, &buf, &len );
      if ( len > 0 ) {
  	if (write(fd, buf, len) == -1) {
  	    ret = -1;
  	}
      }
  
      xmlNanoHTTPClose(ctxt);
      close(fd);
      return(ret);
  }
  
  #ifdef LIBXML_OUTPUT_ENABLED
  /**
   * xmlNanoHTTPSave:
   * @ctxt:  the HTTP context
   * @filename:  the filename where the content should be saved
   *
   * This function saves the output of the HTTP transaction to a file
   * It closes and free the context at the end
   *
   * Returns -1 in case of failure, 0 in case of success.
   */
  int
  xmlNanoHTTPSave(void *ctxt, const char *filename) {
      char *buf = NULL;
      int fd;
      int len;
      int ret = 0;
  
      if ((ctxt == NULL) || (filename == NULL)) return(-1);
  
      if (!strcmp(filename, "-"))
          fd = 1; /* STDOUT_FILENO */
      else {
          fd = open(filename, O_CREAT | O_WRONLY, 0666);
  	if (fd < 0) {
  	    xmlNanoHTTPClose(ctxt);
  	    return(-1);
  	}
      }
  
      xmlNanoHTTPFetchContent( ctxt, &buf, &len );
      if ( len > 0 ) {
  	if (write(fd, buf, len) == -1) {
  	    ret = -1;
  	}
      }
  
      xmlNanoHTTPClose(ctxt);
      close(fd);
      return(ret);
  }
  #endif /* LIBXML_OUTPUT_ENABLED */
  
  /**
   * xmlNanoHTTPReturnCode:
   * @ctx:  the HTTP context
   *
   * Get the latest HTTP return code received
   *
   * Returns the HTTP return code for the request.
   */
  int
  xmlNanoHTTPReturnCode(void *ctx) {
      xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;
  
      if (ctxt == NULL) return(-1);
  
      return(ctxt->returnValue);
  }
  
  /**
   * xmlNanoHTTPAuthHeader:
   * @ctx:  the HTTP context
   *
   * Get the authentication header of an HTTP context
   *
   * Returns the stashed value of the WWW-Authenticate or Proxy-Authenticate
   * header.
   */
  const char *
  xmlNanoHTTPAuthHeader(void *ctx) {
      xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;
  
      if (ctxt == NULL) return(NULL);
  
      return(ctxt->authHeader);
  }
  
  /**
   * xmlNanoHTTPContentLength:
   * @ctx:  the HTTP context
   *
   * Provides the specified content length from the HTTP header.
   *
   * Return the specified content length from the HTTP header.  Note that
   * a value of -1 indicates that the content length element was not included in
   * the response header.
   */
  int
  xmlNanoHTTPContentLength( void * ctx ) {
      xmlNanoHTTPCtxtPtr	ctxt = (xmlNanoHTTPCtxtPtr)ctx;
  
      return ( ( ctxt == NULL ) ? -1 : ctxt->ContentLength );
  }
  
  /**
   * xmlNanoHTTPRedir:
   * @ctx:  the HTTP context
   *
   * Provides the specified redirection URL if available from the HTTP header.
   *
   * Return the specified redirection URL or NULL if not redirected.
   */
  const char *
  xmlNanoHTTPRedir( void * ctx ) {
      xmlNanoHTTPCtxtPtr	ctxt = (xmlNanoHTTPCtxtPtr)ctx;
  
      return ( ( ctxt == NULL ) ? NULL : ctxt->location );
  }
  
  /**
   * xmlNanoHTTPEncoding:
   * @ctx:  the HTTP context
   *
   * Provides the specified encoding if specified in the HTTP headers.
   *
   * Return the specified encoding or NULL if not available
   */
  const char *
  xmlNanoHTTPEncoding( void * ctx ) {
      xmlNanoHTTPCtxtPtr	ctxt = (xmlNanoHTTPCtxtPtr)ctx;
  
      return ( ( ctxt == NULL ) ? NULL : ctxt->encoding );
  }
  
  /**
   * xmlNanoHTTPMimeType:
   * @ctx:  the HTTP context
   *
   * Provides the specified Mime-Type if specified in the HTTP headers.
   *
   * Return the specified Mime-Type or NULL if not available
   */
  const char *
  xmlNanoHTTPMimeType( void * ctx ) {
      xmlNanoHTTPCtxtPtr	ctxt = (xmlNanoHTTPCtxtPtr)ctx;
  
      return ( ( ctxt == NULL ) ? NULL : ctxt->mimeType );
  }
  
  /**
   * xmlNanoHTTPFetchContent:
   * @ctx:  the HTTP context
   * @ptr:  pointer to set to the content buffer.
   * @len:  integer pointer to hold the length of the content
   *
   * Check if all the content was read
   *
   * Returns 0 if all the content was read and available, returns
   * -1 if received content length was less than specified or an error
   * occurred.
   */
  static int
  xmlNanoHTTPFetchContent( void * ctx, char ** ptr, int * len ) {
      xmlNanoHTTPCtxtPtr	ctxt = (xmlNanoHTTPCtxtPtr)ctx;
  
      int			rc = 0;
      int			cur_lgth;
      int			rcvd_lgth;
      int			dummy_int;
      char *		dummy_ptr = NULL;
  
      /*  Dummy up return input parameters if not provided  */
  
      if ( len == NULL )
          len = &dummy_int;
  
      if ( ptr == NULL )
          ptr = &dummy_ptr;
  
      /*  But can't work without the context pointer  */
  
      if ( ( ctxt == NULL ) || ( ctxt->content == NULL ) ) {
          *len = 0;
  	*ptr = NULL;
  	return ( -1 );
      }
  
      rcvd_lgth = ctxt->inptr - ctxt->content;
  
      while ( (cur_lgth = xmlNanoHTTPRecv( ctxt )) > 0 ) {
  
  	rcvd_lgth += cur_lgth;
  	if ( (ctxt->ContentLength > 0) && (rcvd_lgth >= ctxt->ContentLength) )
  	    break;
      }
  
      *ptr = ctxt->content;
      *len = rcvd_lgth;
  
      if ( ( ctxt->ContentLength > 0 ) && ( rcvd_lgth < ctxt->ContentLength ) )
          rc = -1;
      else if ( rcvd_lgth == 0 )
  	rc = -1;
  
      return ( rc );
  }
  
  #endif /* LIBXML_HTTP_ENABLED */
  

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