nanohttp.c

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/*
 * 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 NEED_SOCKETS
#define IN_LIBXML
#include "libxml.h"

#ifdef LIBXML_HTTP_ENABLED
#include <string.h>

#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_RESOLV_H
#ifdef HAVE_ARPA_NAMESER_H
#include <arpa/nameser.h>
#endif
#include <resolv.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h> 
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifndef HAVE_POLL_H
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#else
#include <poll.h>
#endif
#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif
#ifdef SUPPORT_IP6
#include <resolv.h>
#endif
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#endif


#ifdef VMS
#include <stropts>
#define XML_SOCKLEN_T unsigned int
#endif

#if defined(__MINGW32__) || defined(_WIN32_WCE)
#ifndef _WINSOCKAPI_
#define _WINSOCKAPI_
#endif
#include <wsockcompat.h>
#include <winsock2.h>
#undef XML_SOCKLEN_T
#define XML_SOCKLEN_T unsigned int
#endif

#include <libxml/globals.h>
#include <libxml/xmlerror.h>
#include <libxml/xmlmemory.h>
#include <libxml/parser.h> /* for xmlStr(n)casecmp() */
#include <libxml/nanohttp.h>
#include <libxml/globals.h>
#include <libxml/uri.h>

#ifndef _WINSOCKAPI_
#if !defined(__BEOS__) || defined(__HAIKU__)
#define closesocket(s) close(s)
#endif
#define SOCKET int
#define INVALID_SOCKET (-1)
#endif

#ifdef __BEOS__
#ifndef PF_INET
#define PF_INET AF_INET
#endif
#endif

#ifndef XML_SOCKLEN_T
#define XML_SOCKLEN_T unsigned int
#endif

#ifdef STANDALONE
#define DEBUG_HTTP
#define xmlStrncasecmp(a, b, n) strncasecmp((char *)a, (char *)b, n)
#define xmlStrcasecmpi(a, b) strcasecmp((char *)a, (char *)b)
#endif

#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

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 HAVE_ZLIB_H
    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 );

static void
xmlHTTPErrMemory(const char *extra)
{
    __xmlSimpleError(XML_FROM_HTTP, XML_ERR_NO_MEMORY, NULL, NULL, extra);
}

static int socket_errno(void) {
#ifdef _WINSOCKAPI_
    return(WSAGetLastError());
#else
    return(errno);
#endif
}

#ifdef SUPPORT_IP6
static
int have_ipv6(void) {
    SOCKET s;

    s = socket (AF_INET6, SOCK_STREAM, 0);
    if (s != INVALID_SOCKET) {
    close (s);
    return (1);
    }
    return (0);
}
#endif

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;
}

void
xmlNanoHTTPCleanup(void) {
    if (proxy != NULL) {
    xmlFree(proxy);
    proxy = NULL;
    }
#ifdef _WINSOCKAPI_
    if (initialized)
    WSACleanup();
#endif
    initialized = 0;
    return;
}

static void
xmlNanoHTTPScanURL(xmlNanoHTTPCtxtPtr ctxt, const char *URL) {
    xmlURIPtr uri;
    /*
     * 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);
    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);
}

void
xmlNanoHTTPScanProxy(const char *URL) {
    xmlURIPtr uri;

    if (proxy != NULL) { 
        xmlFree(proxy);
    proxy = NULL;
    }
    proxyPort = 0;

#ifdef DEBUG_HTTP
    if (URL == NULL)
    xmlGenericError(xmlGenericErrorContext,
        "Removing HTTP proxy info\n");
    else
    xmlGenericError(xmlGenericErrorContext,
        "Using HTTP proxy %s\n", URL);
#endif
    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);
}

static xmlNanoHTTPCtxtPtr
xmlNanoHTTPNewCtxt(const char *URL) {
    xmlNanoHTTPCtxtPtr ret;

    ret = (xmlNanoHTTPCtxtPtr) xmlMalloc(sizeof(xmlNanoHTTPCtxt));
    if (ret == NULL) {
        xmlHTTPErrMemory("allocating context");
        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);
}

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 HAVE_ZLIB_H
    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);
}

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, 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;
}

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 = (char *) xmlMallocAtomic(65000 * sizeof(char));
            if (ctxt->in == NULL) {
                xmlHTTPErrMemory("allocating input");
                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("allocating input buffer");
                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)
            && (errno != EINTR)
#endif
            )
            return (0);
#endif /* !HAVE_POLL_H */
    }
    return (0);
}

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));
}


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 HAVE_ZLIB_H
    } 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 );
    }
}

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) {
#ifdef DEBUG_HTTP
        perror("socket");
#endif
        __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 defined(__BEOS__) && !defined(__HAIKU__)
    {
        bool noblock = true;

        status =
            setsockopt(s, SOL_SOCKET, SO_NONBLOCK, &noblock,
                       sizeof(noblock));
    }
#else /* __BEOS__ */
    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) {
#ifdef DEBUG_HTTP
        perror("nonblocking");
#endif
        __xmlIOErr(XML_FROM_HTTP, 0, "error setting non-blocking IO\n");
        closesocket(s);
        return INVALID_SOCKET;
    }
#endif /* !__BEOS__ */
#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");
            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);
}

static SOCKET
xmlNanoHTTPConnectHost(const char *host, int port)
{
    struct hostent *h;
    struct sockaddr *addr = NULL;
    struct in_addr ia;
    struct sockaddr_in sockin;

#ifdef SUPPORT_IP6
    struct in6_addr ia6;
    struct sockaddr_in6 sockin6;
#endif
    int i;
    SOCKET s;

    memset (&sockin, 0, sizeof(sockin));
#ifdef SUPPORT_IP6
    memset (&sockin6, 0, sizeof(sockin6));
#endif

#if !defined(HAVE_GETADDRINFO) && defined(SUPPORT_IP6) && defined(RES_USE_INET6)
    if (have_ipv6 ())
    {
    if (!(_res.options & RES_INIT))
        res_init();
    _res.options |= RES_USE_INET6;
    }
#endif

#if defined(HAVE_GETADDRINFO) && defined(SUPPORT_IP6) && !defined(_WIN32)
    if (have_ipv6 ())
#endif
#if defined(HAVE_GETADDRINFO) && (defined(SUPPORT_IP6) || defined(_WIN32))
    {
    int status;
    struct addrinfo hints, *res, *result;

    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 (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;
#ifdef SUPPORT_IP6
        } else if (have_ipv6 () && (res->ai_family == AF_INET6)) {
        if (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;
#endif
        } else
        continue;              /* for */

        s = xmlNanoHTTPConnectAttempt (addr);
        if (s != INVALID_SOCKET) {
        freeaddrinfo (result);
        return (s);
        }
    }

    if (result)
        freeaddrinfo (result);
    }
#endif
#if defined(HAVE_GETADDRINFO) && defined(SUPPORT_IP6) && !defined(_WIN32)
    else
#endif
#if !defined(HAVE_GETADDRINFO) || !defined(_WIN32)
    {
    h = gethostbyname (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(HAVE_NETDB_H) && defined(HOST_NOT_FOUND) && defined(linux)
        const char *h_err_txt = "";

        switch (h_errno) {
        case HOST_NOT_FOUND:
            h_err_txt = "Authoritive host not found";
            break;

        case TRY_AGAIN:
            h_err_txt =
            "Non-authoritive host not found or server failure.";
            break;

        case NO_RECOVERY:
            h_err_txt =
            "Non-recoverable errors:  FORMERR, REFUSED, or NOTIMP.";
            break;

        case NO_ADDRESS:
            h_err_txt =
            "Valid name, no data record of requested type.";
            break;

        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 = (u_short)htons ((unsigned short)port);
        addr = (struct sockaddr *) &sockin;
#ifdef SUPPORT_IP6
        } else if (have_ipv6 () && (h->h_addrtype == AF_INET6)) {
        /* AAAA records (IPv6) */
        if ((unsigned int) h->h_length > sizeof(ia6)) {
            __xmlIOErr(XML_FROM_HTTP, 0, "address size mismatch\n");
            return INVALID_SOCKET;
        }
        memcpy (&ia6, h->h_addr_list[i], h->h_length);
        sockin6.sin6_family = h->h_addrtype;
        sockin6.sin6_addr = ia6;
        sockin6.sin6_port = htons (port);
        addr = (struct sockaddr *) &sockin6;
#endif
        } else
        break;              /* for */

        s = xmlNanoHTTPConnectAttempt (addr);
        if (s != INVALID_SOCKET)
        return (s);
    }
    }
#endif

#ifdef DEBUG_HTTP
    xmlGenericError(xmlGenericErrorContext,
                    "xmlNanoHTTPConnectHost:  unable to connect to '%s'.\n",
                    host);
#endif
    return INVALID_SOCKET;
}


void*
xmlNanoHTTPOpen(const char *URL, char **contentType) {
    if (contentType != NULL) *contentType = NULL;
    return(xmlNanoHTTPMethod(URL, NULL, NULL, contentType, NULL, 0));
}

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));
}

int
xmlNanoHTTPRead(void *ctx, void *dest, int len) {
    xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;
#ifdef HAVE_ZLIB_H
    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 HAVE_ZLIB_H
    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;
    memcpy(dest, ctxt->inrptr, len);
    ctxt->inrptr += len;
    return(len);
}

void
xmlNanoHTTPClose(void *ctx) {
    xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;

    if (ctx == NULL) return;

    xmlNanoHTTPFreeCtxt(ctxt);
}

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;
    char *redirURL = NULL;
#ifdef DEBUG_HTTP
    int xmt_bytes;
#endif
    
    if (URL == NULL) return(NULL);
    if (method == NULL) method = "GET";
    xmlNanoHTTPInit();

retry:
    if (redirURL == NULL)
    ctxt = xmlNanoHTTPNewCtxt(URL);
    else {
    ctxt = xmlNanoHTTPNewCtxt(redirURL);
    ctxt->location = xmlMemStrdup(redirURL);
    }

    if ( ctxt == NULL ) {
    return ( NULL );
    }

    if ((ctxt->protocol == NULL) || (strcmp(ctxt->protocol, "http"))) {
    __xmlIOErr(XML_FROM_HTTP, XML_HTTP_URL_SYNTAX, "Not a valid HTTP URI");
        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);
    }
    if (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 HAVE_ZLIB_H
    /* reserve for possible 'Accept-Encoding: gzip' string */
    blen += 23;
#endif
    if (ctxt->port != 80) {
    /* reserve space for ':xxxxx', incl. potential proxy */
    if (proxy)
        blen += 12;
    else
        blen += 6;
    }
    bp = (char*)xmlMallocAtomic(blen);
    if ( bp == NULL ) {
        xmlNanoHTTPFreeCtxt( ctxt );
    xmlHTTPErrMemory("allocating header buffer");
    return ( NULL );
    }

    p = bp;

    if (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 HAVE_ZLIB_H
    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");

#ifdef DEBUG_HTTP
    xmlGenericError(xmlGenericErrorContext,
        "-> %s%s", proxy? "(Proxy) " : "", bp);
    if ((blen -= strlen(bp)+1) < 0)
    xmlGenericError(xmlGenericErrorContext,
        "ERROR: overflowed buffer by %d bytes\n", -blen);
#endif
    ctxt->outptr = ctxt->out = bp;
    ctxt->state = XML_NANO_HTTP_WRITE;
    blen = strlen( ctxt->out );
#ifdef DEBUG_HTTP
    xmt_bytes = xmlNanoHTTPSend(ctxt, ctxt->out, blen );
    if ( xmt_bytes != blen )
        xmlGenericError( xmlGenericErrorContext,
            "xmlNanoHTTPMethodRedir:  Only %d of %d %s %s\n",
            xmt_bytes, blen,
            "bytes of HTTP headers sent to host",
            ctxt->hostname );
#else
    xmlNanoHTTPSend(ctxt, ctxt->out, blen );
#endif

    if ( input != NULL ) {
#ifdef DEBUG_HTTP
        xmt_bytes = xmlNanoHTTPSend( ctxt, input, ilen );

    if ( xmt_bytes != ilen )
        xmlGenericError( xmlGenericErrorContext,
                "xmlNanoHTTPMethodRedir:  Only %d of %d %s %s\n",
            xmt_bytes, ilen,
            "bytes of HTTP content sent to host",
            ctxt->hostname );
#else
    xmlNanoHTTPSend( ctxt, input, ilen );
#endif
    }

    ctxt->state = XML_NANO_HTTP_READ;

    while ((p = xmlNanoHTTPReadLine(ctxt)) != NULL) {
        if (*p == 0) {
        ctxt->content = ctxt->inrptr;
        xmlFree(p);
        break;
    }
    xmlNanoHTTPScanAnswer(ctxt, p);

#ifdef DEBUG_HTTP
    xmlGenericError(xmlGenericErrorContext, "<- %s\n", p);
#endif
        xmlFree(p);
    }

    if ((ctxt->location != NULL) && (ctxt->returnValue >= 300) &&
        (ctxt->returnValue < 400)) {
#ifdef DEBUG_HTTP
    xmlGenericError(xmlGenericErrorContext,
        "\nRedirect to: %s\n", ctxt->location);
#endif
    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);
#ifdef DEBUG_HTTP
    xmlGenericError(xmlGenericErrorContext,
        "xmlNanoHTTPMethodRedir: Too many redirects, aborting ...\n");
#endif
    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;
    }

#ifdef DEBUG_HTTP
    if (ctxt->contentType != NULL)
    xmlGenericError(xmlGenericErrorContext,
        "\nCode %d, content-type '%s'\n\n",
           ctxt->returnValue, ctxt->contentType);
    else
    xmlGenericError(xmlGenericErrorContext,
        "\nCode %d, no content-type\n\n",
           ctxt->returnValue);
#endif

    return((void *) ctxt);
}

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));
}

int
xmlNanoHTTPFetch(const char *URL, const char *filename, char **contentType) {
    void *ctxt = NULL;
    char *buf = NULL;
    int fd;
    int len;
    
    if (filename == NULL) return(-1);
    ctxt = xmlNanoHTTPOpen(URL, contentType);
    if (ctxt == NULL) return(-1);

    if (!strcmp(filename, "-")) 
        fd = 0;
    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 ) {
    write(fd, buf, len);
    }

    xmlNanoHTTPClose(ctxt);
    close(fd);
    return(0);
}

#ifdef LIBXML_OUTPUT_ENABLED

int
xmlNanoHTTPSave(void *ctxt, const char *filename) {
    char *buf = NULL;
    int fd;
    int len;
    
    if ((ctxt == NULL) || (filename == NULL)) return(-1);

    if (!strcmp(filename, "-")) 
        fd = 0;
    else {
        fd = open(filename, O_CREAT | O_WRONLY, 0666);
    if (fd < 0) {
        xmlNanoHTTPClose(ctxt);
        return(-1);
    }
    }

    xmlNanoHTTPFetchContent( ctxt, &buf, &len );
    if ( len > 0 ) {
    write(fd, buf, len);
    }

    xmlNanoHTTPClose(ctxt);
    close(fd);
    return(0);
}
#endif /* LIBXML_OUTPUT_ENABLED */

int
xmlNanoHTTPReturnCode(void *ctx) {
    xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;

    if (ctxt == NULL) return(-1);

    return(ctxt->returnValue);
}

const char *
xmlNanoHTTPAuthHeader(void *ctx) {
    xmlNanoHTTPCtxtPtr ctxt = (xmlNanoHTTPCtxtPtr) ctx;

    if (ctxt == NULL) return(NULL);

    return(ctxt->authHeader);
}

int
xmlNanoHTTPContentLength( void * ctx ) {
    xmlNanoHTTPCtxtPtr  ctxt = (xmlNanoHTTPCtxtPtr)ctx;

    return ( ( ctxt == NULL ) ? -1 : ctxt->ContentLength );
}

const char *
xmlNanoHTTPRedir( void * ctx ) {
    xmlNanoHTTPCtxtPtr  ctxt = (xmlNanoHTTPCtxtPtr)ctx;

    return ( ( ctxt == NULL ) ? NULL : ctxt->location );
}

const char *
xmlNanoHTTPEncoding( void * ctx ) {
    xmlNanoHTTPCtxtPtr  ctxt = (xmlNanoHTTPCtxtPtr)ctx;

    return ( ( ctxt == NULL ) ? NULL : ctxt->encoding );
}

const char *
xmlNanoHTTPMimeType( void * ctx ) {
    xmlNanoHTTPCtxtPtr  ctxt = (xmlNanoHTTPCtxtPtr)ctx;

    return ( ( ctxt == NULL ) ? NULL : ctxt->mimeType );
}

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 );
}

#ifdef STANDALONE
int main(int argc, char **argv) {
    char *contentType = NULL;

    if (argv[1] != NULL) {
    if (argv[2] != NULL) 
        xmlNanoHTTPFetch(argv[1], argv[2], &contentType);
        else
        xmlNanoHTTPFetch(argv[1], "-", &contentType);
    if (contentType != NULL) xmlFree(contentType);
    } else {
        xmlGenericError(xmlGenericErrorContext,
        "%s: minimal HTTP GET implementation\n", argv[0]);
        xmlGenericError(xmlGenericErrorContext,
        "\tusage %s [ URL [ filename ] ]\n", argv[0]);
    }
    xmlNanoHTTPCleanup();
    xmlMemoryDump();
    return(0);
}
#endif /* STANDALONE */
#else /* !LIBXML_HTTP_ENABLED */
#ifdef STANDALONE
#include <stdio.h>
int main(int argc, char **argv) {
    xmlGenericError(xmlGenericErrorContext,
        "%s : HTTP support not compiled in\n", argv[0]);
    return(0);
}
#endif /* STANDALONE */
#endif /* LIBXML_HTTP_ENABLED */
#define bottom_nanohttp
#include "elfgcchack.h"