/*
* $LynxId: HTMLGen.c,v 1.45 2018/05/11 22:41:59 tom Exp $
*
* HTML Generator
* ==============
*
* This version of the HTML object sends HTML markup to the output stream.
*
* Bugs: Line wrapping is not done at all.
* All data handled as PCDATA.
* Should convert old XMP, LISTING and PLAINTEXT to PRE.
*
* It is not obvious to me right now whether the HEAD should be generated
* from the incomming data or the anchor. Currently it is from the former
* which is cleanest.
*/
#define HTSTREAM_INTERNAL 1
#include <HTUtils.h>
#define BUFFER_SIZE 200 /* Line buffer attempts to make neat breaks */
#define MAX_CLEANNESS 20
/* Implements:
*/
#include <HTMLGen.h>
#include <HTMLDTD.h>
#include <HTStream.h>
#include <SGML.h>
#include <HTFormat.h>
#ifdef USE_COLOR_STYLE
#include <LYCharUtils.h>
#include <AttrList.h>
#include <LYHash.h>
#include <LYStyle.h>
#endif
#include <LYGlobalDefs.h>
#include <LYCurses.h>
#include <LYLeaks.h>
#ifdef USE_COLOR_STYLE
char class_string[TEMPSTRINGSIZE + 1];
static char *Style_className = NULL;
static int hcode;
#endif
/* HTML Object
* -----------
*/
struct _HTStream {
const HTStreamClass *isa;
HTStream *target;
HTStreamClass targetClass; /* COPY for speed */
};
struct _HTStructured {
const HTStructuredClass *isa;
HTStream *target;
HTStreamClass targetClass; /* COPY for speed */
char buffer[BUFFER_SIZE + 1]; /* 1for NL */
int buffer_maxchars;
char *write_pointer;
char *line_break[MAX_CLEANNESS + 1];
int cleanness;
BOOL overflowed;
BOOL delete_line_break_char[MAX_CLEANNESS + 1];
BOOL preformatted;
BOOL escape_specials;
BOOL in_attrval;
#ifdef USE_COLOR_STYLE
HText *text;
#endif
};
/* Flush Buffer
* ------------
*/
static void flush_breaks(HTStructured * me)
{
int i;
for (i = 0; i <= MAX_CLEANNESS; i++) {
me->line_break[i] = NULL;
}
}
static void HTMLGen_flush(HTStructured * me)
{
(*me->targetClass.put_block) (me->target,
me->buffer,
(int) (me->write_pointer - me->buffer));
me->write_pointer = me->buffer;
flush_breaks(me);
me->cleanness = 0;
me->delete_line_break_char[0] = NO;
}
#ifdef USE_COLOR_STYLE
/*
* We need to flush our buffer each time before we effect a color style change,
* this also relies on the subsequent stage not doing any buffering - this is
* currently true, in cases where it matters the target stream should be the
* HTPlain converter. The flushing currently prevents reasonable line breaking
* in lines with tags. Since color styles help visual scanning of displayed
* source lines, and long lines are wrapped in GridText anyway, this is
* probably acceptable (or even A Good Thing - more to see in one screenful).
* The pointer to the HText structure is initialized here before we effect the
* first style change. Getting it from the global HTMainText variable isn't
* very clean, since it relies on the fact that HText_new() has already been
* called for the current stream stack's document by the time we start
* processing the first element; we rely on HTMLGenerator's callers
* (HTMLParsedPresent in particular) to guarantee this when it matters.
* Normally the target stream will have been setup by HTPlainPresent, which
* does what we need in this respect. (A check whether we have the right
* output stream could be done by checking that targetClass.name is
* "PlainPresenter" or similar.)
*
* All special color style handling is only done if LYPreparsedSource is set.
* We could always do it for displaying source generated by an internal
* gateway, but this makes the rule more simple for the user: color styles are
* applied to html source only with the -preparsed flag. - kw
*/
static void do_cstyle_flush(HTStructured * me)
{
if (!me->text && LYPreparsedSource) {
me->text = HTMainText;
}
if (me->text) {
HTMLGen_flush(me);
}
}
#endif /* COLOR_STYLE */
/* Weighted optional line break
*
* We keep track of all the breaks for when we chop the line
*/
static void allow_break(HTStructured * me, int new_cleanness, int dlbc)
{
if (dlbc && me->write_pointer == me->buffer)
dlbc = NO;
me->line_break[new_cleanness] =
dlbc ? me->write_pointer - 1 /* Point to space */
: me->write_pointer; /* point to gap */
me->delete_line_break_char[new_cleanness] = (BOOLEAN) dlbc;
if (new_cleanness >= me->cleanness &&
(me->overflowed || me->line_break[new_cleanness] > me->buffer))
me->cleanness = new_cleanness;
}
/* Character handling
* ------------------
*
* The tricky bits are the line break handling. This attempts
* to synchrononise line breaks on sentence or phrase ends. This
* is important if one stores SGML files in a line-oriented code
* repository, so that if a small change is made, line ends don't
* shift in a ripple-through to apparently change a large part of the
* file. We give extra "cleanness" to spaces appearing directly
* after periods (full stops), [semi]colons and commas.
* This should make the source files easier to read and modify
* by hand, too, though this is not a primary design consideration. TBL
*/
static void HTMLGen_put_character(HTStructured * me, int c)
{
if (me->escape_specials && UCH(c) < 32) {
if (c == HT_NON_BREAK_SPACE || c == HT_EN_SPACE ||
c == LY_SOFT_HYPHEN) { /* recursion... */
HTMLGen_put_character(me, '&');
HTMLGen_put_character(me, '#');
HTMLGen_put_character(me, 'x');
switch (c) {
case HT_NON_BREAK_SPACE: /*   */
HTMLGen_put_character(me, 'A');
HTMLGen_put_character(me, '0');
break;
case HT_EN_SPACE: /*   */
HTMLGen_put_character(me, '2');
HTMLGen_put_character(me, '0');
HTMLGen_put_character(me, '0');
HTMLGen_put_character(me, '2');
break;
case LY_SOFT_HYPHEN: /* ­ */
HTMLGen_put_character(me, 'A');
HTMLGen_put_character(me, 'D');
break;
}
c = ';';
}
}
*me->write_pointer++ = (char) c;
if (c == '\n') {
HTMLGen_flush(me);
return;
}
/* Figure our whether we can break at this point
*/
if ((!me->preformatted && (c == ' ' || c == '\t'))) {
int new_cleanness = 3;
if (me->write_pointer > (me->buffer + 1)) {
char delims[5];
char *p;
strcpy(delims, ",;:."); /* @@ english bias */
p = StrChr(delims, me->write_pointer[-2]);
if (p)
new_cleanness = (int) (p - delims + 6);
if (!me->in_attrval)
new_cleanness += 10;
}
allow_break(me, new_cleanness, YES);
}
/*
* Flush buffer out when full, or whenever the line is over the nominal
* maximum and we can break at all
*/
if (me->write_pointer >= me->buffer + me->buffer_maxchars ||
(me->overflowed && me->cleanness)) {
if (me->cleanness) {
char line_break_char = me->line_break[me->cleanness][0];
char *saved = me->line_break[me->cleanness];
if (me->delete_line_break_char[me->cleanness])
saved++;
me->line_break[me->cleanness][0] = '\n';
(*me->targetClass.put_block) (me->target,
me->buffer,
(int) (me->line_break[me->cleanness] -
me->buffer + 1));
me->line_break[me->cleanness][0] = line_break_char;
{ /* move next line in */
char *p = saved;
char *q;
for (q = me->buffer; p < me->write_pointer;)
*q++ = *p++;
}
me->cleanness = 0;
/* Now we have to check whether ther are any perfectly good breaks
* which weren't good enough for the last line but may be good
* enough for the next
*/
{
int i;
for (i = 0; i <= MAX_CLEANNESS; i++) {
if (me->line_break[i] != NULL &&
me->line_break[i] > saved) {
me->line_break[i] = me->line_break[i] -
(saved - me->buffer);
me->cleanness = i;
} else {
me->line_break[i] = NULL;
}
}
}
me->delete_line_break_char[0] = 0;
me->write_pointer = me->write_pointer - (saved - me->buffer);
me->overflowed = NO;
} else {
(*me->targetClass.put_block) (me->target,
me->buffer,
me->buffer_maxchars);
me->write_pointer = me->buffer;
flush_breaks(me);
me->overflowed = YES;
}
}
}
/* String handling
* ---------------
*/
static void HTMLGen_put_string(HTStructured * me, const char *s)
{
const char *p;
for (p = s; *p; p++)
HTMLGen_put_character(me, *p);
}
static void HTMLGen_write(HTStructured * me, const char *s,
int l)
{
const char *p;
for (p = s; p < (s + l); p++)
HTMLGen_put_character(me, *p);
}
/* Start Element
* -------------
*
* Within the opening tag, there may be spaces and the line may be broken at
* these spaces.
*/
static int HTMLGen_start_element(HTStructured * me, int element_number,
const BOOL *present,
STRING2PTR value,
int charset GCC_UNUSED,
char **insert GCC_UNUSED)
{
int i;
BOOL was_preformatted = me->preformatted;
HTTag *tag = &HTML_dtd.tags[element_number];
#if defined(USE_COLOR_STYLE)
char *title = NULL;
char *title_tmp = NULL;
const char *name;
if (LYPreparsedSource && (name = tag->name) != 0) {
char *myHash = NULL;
/*
* Same logic as in HTML_start_element, copied from there. - kw
*/
HTSprintf(&Style_className, ";%s", name);
StrAllocCopy(myHash, name);
if (class_string[0]) {
StrAllocCat(myHash, ".");
StrAllocCat(myHash, class_string);
HTSprintf(&Style_className, ".%s", class_string);
}
class_string[0] = '\0';
strtolower(myHash);
hcode = color_style_1(myHash);
strtolower(Style_className);
if (TRACE_STYLE) {
fprintf(tfp, "CSSTRIM:%s -> %d", myHash, hcode);
if (!hashStyles[hcode].used) {
char *rp = strrchr(myHash, '.');
fprintf(tfp, " (undefined) %s\n", myHash);
if (rp) {
int hcd;
*rp = '\0'; /* trim the class */
hcd = color_style_1(myHash);
fprintf(tfp, "CSS:%s -> %d", myHash, hcd);
if (!hashStyles[hcd].used)
fprintf(tfp, " (undefined) %s\n", myHash);
else
fprintf(tfp, " ca=%d\n", hashStyles[hcd].color);
}
} else
fprintf(tfp, " ca=%d\n", hashStyles[hcode].color);
}
if (displayStyles[element_number + STARTAT].color > -2) {
CTRACE2(TRACE_STYLE,
(tfp, "CSSTRIM: start_element: top <%s>\n",
tag->name));
do_cstyle_flush(me);
HText_characterStyle(me->text, hcode, 1);
}
FREE(myHash);
}
#endif /* USE_COLOR_STYLE */
me->preformatted = YES; /* free text within tags */
HTMLGen_put_character(me, '<');
HTMLGen_put_string(me, tag->name);
if (present) {
BOOL had_attr = NO;
for (i = 0; i < tag->number_of_attributes; i++) {
if (present[i]) {
had_attr = YES;
HTMLGen_put_character(me, ' ');
allow_break(me, 11, YES);
#ifdef USE_COLOR_STYLE
/*
* Try to mimic HTML_start_element's special handling for
* HTML_LINK. If applicable, color the displayed attribute /
* value pairs differently. - kw
*/
if (LYPreparsedSource &&
element_number == HTML_LINK && !title &&
present[HTML_LINK_CLASS] && *value[HTML_LINK_CLASS] &&
!present[HTML_LINK_REV] &&
(present[HTML_LINK_REL] || present[HTML_LINK_HREF])) {
if (present[HTML_LINK_TITLE] && *value[HTML_LINK_TITLE]) {
StrAllocCopy(title, value[HTML_LINK_TITLE]);
LYTrimHead(title);
LYTrimTail(title);
}
if ((!title || *title == '\0') && present[HTML_LINK_REL]) {
StrAllocCopy(title, value[HTML_LINK_REL]);
}
if (title && *title) {
HTSprintf0(&title_tmp, "link.%s.%s",
value[HTML_LINK_CLASS], title);
CTRACE2(TRACE_STYLE,
(tfp, "CSSTRIM:link=%s\n", title_tmp));
do_cstyle_flush(me);
HText_characterStyle(me->text,
color_style_1(title_tmp), 1);
}
}
#endif
HTMLGen_put_string(me, tag->attributes[i].name);
if (value[i]) {
me->preformatted = was_preformatted;
me->in_attrval = YES;
if (StrChr(value[i], '"') == NULL) {
HTMLGen_put_string(me, "=\"");
HTMLGen_put_string(me, value[i]);
HTMLGen_put_character(me, '"');
} else if (StrChr(value[i], '\'') == NULL) {
HTMLGen_put_string(me, "='");
HTMLGen_put_string(me, value[i]);
HTMLGen_put_character(me, '\'');
} else { /* attribute value has both kinds of quotes */
const char *p;
HTMLGen_put_string(me, "=\"");
for (p = value[i]; *p; p++) {
if (*p != '"') {
HTMLGen_put_character(me, *p);
} else {
HTMLGen_put_string(me, """);
}
}
HTMLGen_put_character(me, '"');
}
me->preformatted = YES;
me->in_attrval = NO;
}
}
}
#ifdef USE_COLOR_STYLE
if (had_attr && LYPreparsedSource && element_number == HTML_LINK) {
/*
* Clean up after special HTML_LINK handling - kw
*/
if (title && *title) {
do_cstyle_flush(me);
HText_characterStyle(me->text, color_style_1(title_tmp), 0);
FREE(title_tmp);
}
FREE(title);
}
#endif
if (had_attr)
allow_break(me, 12, NO);
}
HTMLGen_put_string(me, ">"); /* got rid of \n LJM */
/*
* Make very specific HTML assumption that PRE can't be nested!
*/
me->preformatted = (BOOL) ((element_number == HTML_PRE)
? YES
: was_preformatted);
/*
* Can break after element start.
*/
if (!me->preformatted && tag->contents != SGML_EMPTY) {
if (tag->contents == SGML_ELEMENT)
allow_break(me, 15, NO);
else
allow_break(me, 2, NO);
}
#if defined(USE_COLOR_STYLE)
/*
* Same logic as in HTML_start_element, copied from there. - kw
*/
/* end really empty tags straight away */
if (LYPreparsedSource && ReallyEmptyTagNum(element_number)) {
CTRACE2(TRACE_STYLE,
(tfp, "STYLE:begin_element:ending EMPTY element style\n"));
do_cstyle_flush(me);
HText_characterStyle(me->text, hcode, STACK_OFF);
TrimColorClass(tag->name, Style_className, &hcode);
}
#endif /* USE_COLOR_STYLE */
if (element_number == HTML_OBJECT && tag->contents == SGML_LITTERAL) {
/*
* These conditions only approximate the ones used in HTML.c. Let our
* SGML parser know that further content is to be parsed normally not
* literally. - kw
*/
if (!present) {
return HT_PARSER_OTHER_CONTENT;
} else if (!present[HTML_OBJECT_DECLARE] &&
!(present[HTML_OBJECT_NAME] &&
value[HTML_OBJECT_NAME] && *value[HTML_OBJECT_NAME])) {
if (present[HTML_OBJECT_SHAPES] ||
!(present[HTML_OBJECT_USEMAP] &&
value[HTML_OBJECT_USEMAP] && *value[HTML_OBJECT_USEMAP]))
return HT_PARSER_OTHER_CONTENT;
}
}
return HT_OK;
}
/* End Element
* -----------
*
* When we end an element, the style must be returned to that in effect before
* that element. Note that anchors (etc?) don't have an associated style, so
* that we must scan down the stack for an element with a defined style. (In
* fact, the styles should be linked to the whole stack not just the top one.)
* TBL 921119
*/
static int HTMLGen_end_element(HTStructured * me, int element_number,
char **insert GCC_UNUSED)
{
if (!me->preformatted &&
HTML_dtd.tags[element_number].contents != SGML_EMPTY) {
/*
* Can break before element end.
*/
if (HTML_dtd.tags[element_number].contents == SGML_ELEMENT)
allow_break(me, 14, NO);
else
allow_break(me, 1, NO);
}
HTMLGen_put_string(me, "</");
HTMLGen_put_string(me, HTML_dtd.tags[element_number].name);
HTMLGen_put_character(me, '>');
if (element_number == HTML_PRE) {
me->preformatted = NO;
}
#ifdef USE_COLOR_STYLE
/*
* Same logic as in HTML_end_element, copied from there. - kw
*/
TrimColorClass(HTML_dtd.tags[element_number].name,
Style_className, &hcode);
if (LYPreparsedSource && !ReallyEmptyTagNum(element_number)) {
CTRACE2(TRACE_STYLE,
(tfp, "STYLE:end_element: ending non-EMPTY style\n"));
do_cstyle_flush(me);
HText_characterStyle(me->text, hcode, STACK_OFF);
}
#endif /* USE_COLOR_STYLE */
return HT_OK;
}
/* Expanding entities
* ------------------
*
*/
static int HTMLGen_put_entity(HTStructured * me, int entity_number)
{
int nent = (int) HTML_dtd.number_of_entities;
HTMLGen_put_character(me, '&');
if (entity_number < nent) {
HTMLGen_put_string(me, HTML_dtd.entity_names[entity_number]);
}
HTMLGen_put_character(me, ';');
return HT_OK;
}
/* Free an HTML object
* -------------------
*
*/
static void HTMLGen_free(HTStructured * me)
{
(*me->targetClass.put_character) (me->target, '\n');
HTMLGen_flush(me);
(*me->targetClass._free) (me->target); /* ripple through */
#ifdef USE_COLOR_STYLE
FREE(Style_className);
#endif
FREE(me);
}
static void PlainToHTML_free(HTStructured * me)
{
HTMLGen_end_element(me, HTML_PRE, 0);
HTMLGen_free(me);
}
static void HTMLGen_abort(HTStructured * me, HTError e GCC_UNUSED)
{
HTMLGen_free(me);
#ifdef USE_COLOR_STYLE
FREE(Style_className);
#endif
}
static void PlainToHTML_abort(HTStructured * me, HTError e GCC_UNUSED)
{
PlainToHTML_free(me);
}
/* Structured Object Class
* -----------------------
*/
static const HTStructuredClass HTMLGeneration = /* As opposed to print etc */
{
"HTMLGen",
HTMLGen_free,
HTMLGen_abort,
HTMLGen_put_character, HTMLGen_put_string, HTMLGen_write,
HTMLGen_start_element, HTMLGen_end_element,
HTMLGen_put_entity
};
/* Subclass-specific Methods
* -------------------------
*/
HTStructured *HTMLGenerator(HTStream *output)
{
HTStructured *me = (HTStructured *) malloc(sizeof(*me));
if (me == NULL)
outofmem(__FILE__, "HTMLGenerator");
me->isa = &HTMLGeneration;
me->target = output;
me->targetClass = *me->target->isa; /* Copy pointers to routines for speed */
me->write_pointer = me->buffer;
flush_breaks(me);
me->line_break[0] = me->buffer;
me->cleanness = 0;
me->overflowed = NO;
me->delete_line_break_char[0] = NO;
me->preformatted = NO;
me->in_attrval = NO;
/*
* For what line length should we attempt to wrap ? - kw
*/
if (!LYPreparsedSource) {
me->buffer_maxchars = 80; /* work as before - kw */
} else if (dump_output_width > 1) {
me->buffer_maxchars = dump_output_width; /* try to honor -width - kw */
} else if (dump_output_immediately) {
me->buffer_maxchars = 80; /* try to honor -width - kw */
} else {
me->buffer_maxchars = (LYcolLimit - 1);
if (me->buffer_maxchars < 38) /* too narrow, let GridText deal */
me->buffer_maxchars = 40;
}
if (me->buffer_maxchars > 900) /* likely not true - kw */
me->buffer_maxchars = 78;
if (me->buffer_maxchars > BUFFER_SIZE) /* must not be larger! */
me->buffer_maxchars = BUFFER_SIZE - 2;
/*
* If dump_output_immediately is set, there likely isn't anything after
* this stream to interpret the Lynx special chars. Also if they get
* displayed via HTPlain, that will probably make non-breaking space chars
* etc. invisible. So let's translate them to numerical character
* references. For debugging purposes we'll use the new hex format.
*/
me->escape_specials = LYPreparsedSource;
#ifdef USE_COLOR_STYLE
me->text = NULL; /* Will be initialized when first needed. - kw */
FREE(Style_className);
class_string[0] = '\0';
#endif /* COLOR_STYLE */
return me;
}
/* Stream Object Class
* -------------------
*
* This object just converts a plain text stream into HTML
* It is officially a structured strem but only the stream bits exist.
* This is just the easiest way of typecasting all the routines.
*/
static const HTStructuredClass PlainToHTMLConversion =
{
"plaintexttoHTML",
HTMLGen_free,
PlainToHTML_abort,
HTMLGen_put_character,
HTMLGen_put_string,
HTMLGen_write,
NULL, /* Structured stuff */
NULL,
NULL
};
/* HTConverter from plain text to HTML Stream
* ------------------------------------------
*/
HTStream *HTPlainToHTML(HTPresentation *pres GCC_UNUSED,
HTParentAnchor *anchor GCC_UNUSED,
HTStream *sink)
{
HTStructured *me = (HTStructured *) malloc(sizeof(*me));
if (me == NULL)
outofmem(__FILE__, "PlainToHTML");
me->isa = (const HTStructuredClass *) &PlainToHTMLConversion;
/*
* Copy pointers to routines for speed.
*/
me->target = sink;
me->targetClass = *me->target->isa;
me->write_pointer = me->buffer;
flush_breaks(me);
me->cleanness = 0;
me->overflowed = NO;
me->delete_line_break_char[0] = NO;
/* try to honor -width - kw */
me->buffer_maxchars = (dump_output_width > 1 ?
dump_output_width : 80);
HTMLGen_put_string(me, "<HTML>\n<BODY>\n<PRE>\n");
me->preformatted = YES;
me->escape_specials = NO;
me->in_attrval = NO;
return (HTStream *) me;
}