htformat.c

elinks下lynx是最重要的二个文本浏览器, 在linux下非常实用, lynx比elinks早的多, 目前好像停止开发, 这是lynx源代码

    HTAtom * wildcard = WWW_WILDCARD_REP_OUT;

    CTRACE((tfp, "HTFormat: Evaluating stream stack for %s worth %.3f to %s\n",
		HTAtom_name(rep_in), initial_value, HTAtom_name(rep_out)));

    if (rep_out == WWW_SOURCE || rep_out == rep_in)
	return 0.0;

    /* don't do anymore do it in the Lynx code at startup LJM */
    /* if (!HTPresentations) HTFormatInit(); */ /* set up the list */

    {
	int n = HTList_count(HTPresentations);
	int i;
	HTPresentation * pres;
	for (i = 0; i < n; i++) {
	    pres = (HTPresentation *)HTList_objectAt(HTPresentations, i);
	    if (pres->rep == rep_in &&
		(pres->rep_out == rep_out || pres->rep_out == wildcard)) {
		float value = initial_value * pres->quality;
		if (HTMaxSecs != 0.0)
		    value = value - (length*pres->secs_per_byte + pres->secs)
					 /HTMaxSecs;
		return value;
	    }
	}
    }

    return (float) -1e30;	/* Really bad */

}

/*	Display the page while transfer in progress
**	-------------------------------------------
**
**   Repaint the page only when necessary.
**   This is a traverse call for HText_pageDisplay() - it works!.
**
*/
PUBLIC void HTDisplayPartial NOARGS
{
#ifdef DISP_PARTIAL
    if (display_partial) {
	/*
	**  HText_getNumOfLines() = "current" number of complete lines received
	**  NumOfLines_partial = number of lines at the moment of last repaint.
	**  (we update NumOfLines_partial only when we repaint the display.)
	**
	**  display_partial could only be enabled in HText_new()
	**  so a new HTMainText object available - all HText_ functions use it,
	**  lines counter HText_getNumOfLines() in particular.
	**
	**  Otherwise HTMainText holds info from the previous document
	**  and we may repaint it instead of the new one:
	**  prev doc scrolled to the first line (=Newline_partial)
	**  is not good looking :-)	  23 Aug 1998 Leonid Pauzner
	**
	**  So repaint the page only when necessary:
	*/
	int Newline_partial = LYGetNewline();

	if (((Newline_partial + display_lines) - 1 > NumOfLines_partial)
		/* current page not complete... */
	&& (partial_threshold > 0 ?
		((Newline_partial + partial_threshold) -1 <= HText_getNumOfLines()) :
		((Newline_partial + display_lines) - 1 <= HText_getNumOfLines()))
		/*
		 * Originally we rendered by increments of 2 lines,
		 * but that got annoying on slow network connections.
		 * Then we switched to full-pages.  Now it's configurable.
		 * If partial_threshold <= 0, then it's a full page
		 */
	) {
	    if (LYMainLoop_pageDisplay(Newline_partial))
		NumOfLines_partial = HText_getNumOfLines();
	}
    }
#else /* nothing */
#endif  /* DISP_PARTIAL */
}

/* Put this as early as possible, OK just after HTDisplayPartial() */
PUBLIC void HTFinishDisplayPartial NOARGS
{
#ifdef DISP_PARTIAL
		    /*
		     *  End of incremental rendering stage here.
		     */
		    display_partial = FALSE;
#endif /* DISP_PARTIAL */
}

/*	Push data from a socket down a stream
**	-------------------------------------
**
**   This routine is responsible for creating and PRESENTING any
**   graphic (or other) objects described by the file.
**
**   The file number given is assumed to be a TELNET stream, i.e., containing
**   CRLF at the end of lines which need to be stripped to LF for unix
**   when the format is textual.
**
**  State of socket and target stream on entry:
**			socket (file_number) assumed open,
**			target (sink) assumed valid.
**
**  Return values:
**	HT_INTERRUPTED  Interruption or error after some data received.
**	-2		Unexpected disconnect before any data received.
**	-1		Interruption or error before any data received, or
**			(UNIX) other read error before any data received, or
**			download cancelled.
**	HT_LOADED	Normal close of socket (end of file indication
**			received), or
**			unexpected disconnect after some data received, or
**			other read error after some data received, or
**			(not UNIX) other read error before any data received.
**
**  State of socket and target stream on return depends on return value:
**	HT_INTERRUPTED	socket still open, target aborted.
**	-2		socket still open, target stream still valid.
**	-1		socket still open, target aborted.
**	otherwise	socket closed,	target stream still valid.
*/
PUBLIC int HTCopy ARGS4(
	HTParentAnchor *,	anchor,
	int,			file_number,
	void*,			handle GCC_UNUSED,
	HTStream*,		sink)
{
    HTStreamClass targetClass;
    BOOL suppress_readprogress = NO;
    int bytes;
    int rv = 0;

    /*	Push the data down the stream
    */
    targetClass = *(sink->isa); /* Copy pointers to procedures */

    /*	Push binary from socket down sink
    **
    **	This operation could be put into a main event loop
    */
    HTReadProgress(bytes = 0, 0);
    for (;;) {
	int status;

	if (LYCancelDownload) {
	    LYCancelDownload = FALSE;
	    (*targetClass._abort)(sink, NULL);
	    rv = -1;
	    goto finished;
	}

	if (HTCheckForInterrupt()) {
	    _HTProgress (TRANSFER_INTERRUPTED);
	    (*targetClass._abort)(sink, NULL);
	    if (bytes)
		rv = HT_INTERRUPTED;
	    else
		rv = -1;
	    goto finished;
	}

#ifdef USE_SSL
	if (handle)
	    status = SSL_read((SSL *)handle, input_buffer, INPUT_BUFFER_SIZE);
	else
	    status = NETREAD(file_number, input_buffer, INPUT_BUFFER_SIZE);
#else
	status = NETREAD(file_number, input_buffer, INPUT_BUFFER_SIZE);
#endif /* USE_SSL */

	if (status <= 0) {
	    if (status == 0) {
		break;
	    } else if (status == HT_INTERRUPTED) {
		_HTProgress (TRANSFER_INTERRUPTED);
		(*targetClass._abort)(sink, NULL);
		if (bytes)
		    rv = HT_INTERRUPTED;
		else
		    rv = -1;
		goto finished;
	    } else if (SOCKET_ERRNO == ENOTCONN ||
#ifdef _WINDOWS	/* 1997/11/10 (Mon) 16:57:18 */
		       SOCKET_ERRNO == ETIMEDOUT ||
#endif
		       SOCKET_ERRNO == ECONNRESET ||
		       SOCKET_ERRNO == EPIPE) {
		/*
		 *  Arrrrgh, HTTP 0/1 compatibility problem, maybe.
		 */
		if (bytes <= 0) {
		    /*
		     *	Don't have any data, so let the calling
		     *	function decide what to do about it. - FM
		     */
		    rv = -2;
		    goto finished;
		} else {
#ifdef UNIX
		   /*
		    *  Treat what we've received already as the complete
		    *  transmission, but not without giving the user
		    *  an alert.  I don't know about all the different
		    *  TCP stacks for VMS etc., so this is currently
		    *  only for UNIX. - kw
		    */
		   HTInetStatus("NETREAD");
		   HTAlert("Unexpected server disconnect.");
		   CTRACE((tfp,
	    "HTCopy: Unexpected server disconnect. Treating as completed.\n"));
		   status = 0;
		   break;
#else  /* !UNIX */
		   /*
		    *  Treat what we've gotten already
		    *  as the complete transmission. - FM
		    */
		   CTRACE((tfp,
	    "HTCopy: Unexpected server disconnect.  Treating as completed.\n"));
		   status = 0;
		   break;
#endif /* UNIX */
		}
#ifdef UNIX
	    } else {		/* status < 0 and other errno */
		/*
		 *  Treat what we've received already as the complete
		 *  transmission, but not without giving the user
		 *  an alert.  I don't know about all the different
		 *  TCP stacks for VMS etc., so this is currently
		 *  only for UNIX. - kw
		 */
		HTInetStatus("NETREAD");
		HTAlert("Unexpected read error.");
		if (bytes) {
		    (void)NETCLOSE(file_number);
		    rv = HT_LOADED;
		} else {
		    (*targetClass._abort)(sink, NULL);
		    rv = -1;
		}
		goto finished;
#endif
	    }
	    break;
	}

	/*
	 *  Suppress ReadProgress messages when collecting a redirection
	 *  message, at least initially (unless/until anchor->content_type
	 *  gets changed, probably by the MIME message parser).  That way
	 *  messages put up by the HTTP module or elsewhere can linger in
	 *  the statusline for a while. - kw
	 */
	suppress_readprogress = (anchor && anchor->content_type &&
				 !strcmp(anchor->content_type,
					 "message/x-http-redirection"));
#ifdef NOT_ASCII
	{
	    char * p;
	    for (p = input_buffer; p < input_buffer+status; p++) {
		*p = FROMASCII(*p);
	    }
	}
#endif /* NOT_ASCII */

	(*targetClass.put_block)(sink, input_buffer, status);
	bytes += status;
	if (!suppress_readprogress)
	    HTReadProgress(bytes, anchor ? anchor->content_length : 0);
	HTDisplayPartial();

    } /* next bufferload */

    _HTProgress(TRANSFER_COMPLETE);
    (void)NETCLOSE(file_number);
    rv = HT_LOADED;

finished:
    HTFinishDisplayPartial();
    return(rv);
}

/*	Push data from a file pointer down a stream
**	-------------------------------------
**
**   This routine is responsible for creating and PRESENTING any
**   graphic (or other) objects described by the file.
**
**
**  State of file and target stream on entry:
**			FILE* (fp) assumed open,
**			target (sink) assumed valid.
**
**  Return values:
**	HT_INTERRUPTED  Interruption after some data read.
**	HT_PARTIAL_CONTENT	Error after some data read.
**	-1		Error before any data read.
**	HT_LOADED	Normal end of file indication on reading.
**
**  State of file and target stream on return:
**	always		fp still open, target stream still valid.
*/
PUBLIC int HTFileCopy ARGS2(
	FILE *,			fp,
	HTStream*,		sink)
{
    HTStreamClass targetClass;
    int status, bytes;
    int rv = HT_OK;

    /*	Push the data down the stream
    */
    targetClass = *(sink->isa); /* Copy pointers to procedures */

    /*	Push binary from socket down sink
    */
    HTReadProgress(bytes = 0, 0);
    for (;;) {
	status = fread(input_buffer, 1, INPUT_BUFFER_SIZE, fp);
	if (status == 0) { /* EOF or error */
	    if (ferror(fp) == 0) {
		rv = HT_LOADED;
		break;
	    }
	    CTRACE((tfp, "HTFormat: Read error, read returns %d\n",
			ferror(fp)));
	    if (bytes) {
		rv = HT_PARTIAL_CONTENT;
	    } else {
		rv = -1;
	    }
	    break;
	}

	(*targetClass.put_block)(sink, input_buffer, status);
	bytes += status;
	HTReadProgress(bytes, 0);
	/*  Suppress last screen update in partial mode - a regular update
	 *  under control of mainloop() should follow anyway. - kw
	 */
#ifdef DISP_PARTIAL
	if (display_partial && bytes != HTMainAnchor->content_length)
	    HTDisplayPartial();
#endif

	if (HTCheckForInterrupt()) {
	    _HTProgress (TRANSFER_INTERRUPTED);
	    if (bytes) {
		rv = HT_INTERRUPTED;
	    } else {
		rv = -1;
	    }
	    break;
	}
    } /* next bufferload */

    HTFinishDisplayPartial();
    return rv;
}

#ifdef USE_SOURCE_CACHE
/*	Push data from an HTChunk down a stream
**	---------------------------------------
**
**   This routine is responsible for creating and PRESENTING any
**   graphic (or other) objects described by the file.
**
**  State of memory and target stream on entry:
**			HTChunk* (chunk) and target (sink) assumed valid.
**
**  Return values:
**	HT_LOADED	All data sent.
**	HT_INTERRUPTED  Interruption after some data read.
**
**  State of memory and target stream on return:
**	always		chunk unchanged, target stream still valid.
*/
PUBLIC int HTMemCopy ARGS2(
	HTChunk *,		chunk,
	HTStream *,		sink)
{
    HTStreamClass targetClass;
    int bytes = 0;
    CONST char *data = chunk->data;
    int rv = HT_OK;

    targetClass = *(sink->isa);
    HTReadProgress(0, 0);
    for (;;) {
	/* Push the data down the stream a piece at a time, in case we're
	** running a large document on a slow machine.
	*/
	int n = INPUT_BUFFER_SIZE;
	if (n > chunk->size - bytes)
	    n = chunk->size - bytes;
	if (n == 0)
	    break;
	(*targetClass.put_block)(sink, data, n);
	bytes += n;
	data += n;
	HTReadProgress(bytes, 0);
	HTDisplayPartial();

	if (HTCheckForInterrupt()) {
	    _HTProgress (TRANSFER_INTERRUPTED);
	    if (bytes) {
		rv = HT_INTERRUPTED;
	    } else {
		rv = -1;
	    }
	    break;
	}
    }

    HTFinishDisplayPartial();
    return rv;
}
#endif

#ifdef USE_ZLIB
/*	Push data from a gzip file pointer down a stream
**	-------------------------------------
**
**   This routine is responsible for creating and PRESENTING any
**   graphic (or other) objects described by the file.
**
**
**  State of file and target stream on entry:
**		      gzFile (gzfp) assumed open (should have gzipped content),
**		      target (sink) assumed valid.
**
**  Return values:
**	HT_INTERRUPTED  Interruption after some data read.
**	HT_PARTIAL_CONTENT	Error after some data read.
**	-1		Error before any data read.
**	HT_LOADED	Normal end of file indication on reading.
**
**  State of file and target stream on return:
**	always		gzfp still open, target stream still valid.
*/
PRIVATE int HTGzFileCopy ARGS2(
	gzFile,			gzfp,
	HTStream*,		sink)
{
    HTStreamClass targetClass;
    int status, bytes;
    int gzerrnum;
    int rv = HT_OK;

    /*	Push the data down the stream
    */
    targetClass = *(sink->isa); /* Copy pointers to procedures */

    /*	read and inflate gzip'd file, and push binary down sink
    */
    HTReadProgress(bytes = 0, 0);
    for (;;) {
	status = gzread(gzfp, input_buffer, INPUT_BUFFER_SIZE);
	if (status <= 0) { /* EOF or error */
	    if (status == 0) {
		rv = HT_LOADED;
		break;
	    }
	    CTRACE((tfp, "HTGzFileCopy: Read error, gzread returns %d\n",
			status));
	    CTRACE((tfp, "gzerror   : %s\n",
			gzerror(gzfp, &gzerrnum)));
	    if (TRACE) {
		if (gzerrnum == Z_ERRNO)
		    perror("gzerror   ");
	    }
	    if (bytes) {
		rv = HT_PARTIAL_CONTENT;
	    } else {
		rv = -1;
	    }
	    break;
	}

	(*targetClass.put_block)(sink, input_buffer, status);
	bytes += status;
	HTReadProgress(bytes, -1);
	HTDisplayPartial();

	if (HTCheckForInterrupt()) {
	    _HTProgress (TRANSFER_INTERRUPTED);
	    if (bytes) {
		rv = HT_INTERRUPTED;
	    } else {
		rv = -1;
	    }
	    break;
	}
    } /* next bufferload */

    HTFinishDisplayPartial();
    return rv;
}
#endif /* USE_ZLIB */

#ifdef USE_BZLIB
/*	Push data from a bzip file pointer down a stream
**	-------------------------------------
**
**   This routine is responsible for creating and PRESENTING any
**   graphic (or other) objects described by the file.
**
**
**  State of file and target stream on entry:
**		      BZFILE (bzfp) assumed open (should have bzipped content),
**		      target (sink) assumed valid.
**
**  Return values:
**	HT_INTERRUPTED  Interruption after some data read.
**	HT_PARTIAL_CONTENT	Error after some data read.
**	-1		Error before any data read.
**	HT_LOADED	Normal end of file indication on reading.
**
**  State of file and target stream on return:
**	always		bzfp still open, target stream still valid.
*/
PRIVATE int HTBzFileCopy ARGS2(
	BZFILE *,		bzfp,
	HTStream*,		sink)
{
    HTStreamClass targetClass;
    int status, bytes;
    int bzerrnum;
    int rv = HT_OK;

    /*	Push the data down the stream
    */
    targetClass = *(sink->isa); /* Copy pointers to procedures */

    /*	read and inflate bzip'd file, and push binary down sink
    */
    HTReadProgress(bytes = 0, 0);
    for (;;) {
	status = BZ2_bzread(bzfp, input_buffer, INPUT_BUFFER_SIZE);
	if (status <= 0) { /* EOF or error */
	    if (status == 0) {
		rv = HT_LOADED;
		break;
	    }
	    CTRACE((tfp, "HTBzFileCopy: Read error, bzread returns %d\n",
			status));
	    CTRACE((tfp, "bzerror   : %s\n",
			BZ2_bzerror(bzfp, &bzerrnum)));
	    if (bytes) {
		rv = HT_PARTIAL_CONTENT;
	    } else {