/*
** Copyright (c) 2012 D. Richard Hipp
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the Simplified BSD License (also
** known as the "2-Clause License" or "FreeBSD License".)
** This program is distributed in the hope that it will be useful,
** but without any warranty; without even the implied warranty of
** merchantability or fitness for a particular purpose.
**
** Author contact information:
** drh@hwaci.com
** http://www.hwaci.com/drh/
**
*******************************************************************************
**
** This file contains callbacks for the markdown parser that generate
** XHTML output.
*/
#include "config.h"
#include "markdown_html.h"
#if INTERFACE
void markdown_to_html(
struct Blob *input_markdown,
struct Blob *output_title,
struct Blob *output_body);
#endif /* INTERFACE */
/*
** An instance of the following structure is passed through the
** "opaque" pointer.
*/
typedef struct MarkdownToHtml MarkdownToHtml;
struct MarkdownToHtml {
Blob *output_title; /* Store the title here */
};
/* INTER_BLOCK -- skip a line between block level elements */
#define INTER_BLOCK(ob) \
do { if( blob_size(ob)>0 ) blob_append_char(ob, '\n'); } while (0)
/* BLOB_APPEND_LITERAL -- append a string literal to a blob */
#define BLOB_APPEND_LITERAL(blob, literal) \
blob_append((blob), "" literal, (sizeof literal)-1)
/*
* The empty string in the second argument leads to a syntax error
* when the macro is not used with a string literal. Unfortunately
* the error is not overly explicit.
*/
/* BLOB_APPEND_BLOB -- append blob contents to another */
#define BLOB_APPEND_BLOB(dest, src) \
blob_append((dest), blob_buffer(src), blob_size(src))
/* HTML escapes
**
** html_escape() converts < to <, > to >, and & to &.
** html_quote() goes further and converts " into " and ' in '.
*/
static void html_quote(struct Blob *ob, const char *data, size_t size){
size_t beg = 0, i = 0;
while( i<size ){
beg = i;
while( i<size
&& data[i]!='<'
&& data[i]!='>'
&& data[i]!='"'
&& data[i]!='&'
&& data[i]!='\''
){
i++;
}
blob_append(ob, data+beg, i-beg);
while( i<size ){
if( data[i]=='<' ){
BLOB_APPEND_LITERAL(ob, "<");
}else if( data[i]=='>' ){
BLOB_APPEND_LITERAL(ob, ">");
}else if( data[i]=='&' ){
BLOB_APPEND_LITERAL(ob, "&");
}else if( data[i]=='"' ){
BLOB_APPEND_LITERAL(ob, """);
}else if( data[i]=='\'' ){
BLOB_APPEND_LITERAL(ob, "'");
}else{
break;
}
i++;
}
}
}
static void html_escape(struct Blob *ob, const char *data, size_t size){
size_t beg = 0, i = 0;
while( i<size ){
beg = i;
while( i<size
&& data[i]!='<'
&& data[i]!='>'
&& data[i]!='&'
){
i++;
}
blob_append(ob, data+beg, i-beg);
while( i<size ){
if( data[i]=='<' ){
BLOB_APPEND_LITERAL(ob, "<");
}else if( data[i]=='>' ){
BLOB_APPEND_LITERAL(ob, ">");
}else if( data[i]=='&' ){
BLOB_APPEND_LITERAL(ob, "&");
}else{
break;
}
i++;
}
}
}
/* HTML block tags */
/* Size of the prolog: "<div class='markdown'>\n" */
#define PROLOG_SIZE 23
static void html_prolog(struct Blob *ob, void *opaque){
INTER_BLOCK(ob);
BLOB_APPEND_LITERAL(ob, "<div class=\"markdown\">\n");
assert( blob_size(ob)==PROLOG_SIZE );
}
static void html_epilog(struct Blob *ob, void *opaque){
INTER_BLOCK(ob);
BLOB_APPEND_LITERAL(ob, "</div>\n");
}
static void html_blockhtml(struct Blob *ob, struct Blob *text, void *opaque){
char *data = blob_buffer(text);
size_t size = blob_size(text);
Blob *title = ((MarkdownToHtml*)opaque)->output_title;
while( size>0 && fossil_isspace(data[0]) ){ data++; size--; }
while( size>0 && fossil_isspace(data[size-1]) ){ size--; }
/* If the first raw block is an <h1> element, then use it as the title. */
if( blob_size(ob)<=PROLOG_SIZE
&& size>9
&& title!=0
&& sqlite3_strnicmp("<h1",data,3)==0
&& sqlite3_strnicmp("</h1>", &data[size-5],5)==0
){
int nTag = html_tag_length(data);
blob_append(title, data+nTag, size - nTag - 5);
return;
}
INTER_BLOCK(ob);
blob_append(ob, data, size);
BLOB_APPEND_LITERAL(ob, "\n");
}
static void html_blockcode(struct Blob *ob, struct Blob *text, void *opaque){
INTER_BLOCK(ob);
BLOB_APPEND_LITERAL(ob, "<pre><code>");
html_escape(ob, blob_buffer(text), blob_size(text));
BLOB_APPEND_LITERAL(ob, "</code></pre>\n");
}
static void html_blockquote(struct Blob *ob, struct Blob *text, void *opaque){
INTER_BLOCK(ob);
BLOB_APPEND_LITERAL(ob, "<blockquote>\n");
BLOB_APPEND_BLOB(ob, text);
BLOB_APPEND_LITERAL(ob, "</blockquote>\n");
}
static void html_header(
struct Blob *ob,
struct Blob *text,
int level,
void *opaque
){
struct Blob *title = ((MarkdownToHtml*)opaque)->output_title;
/* The first header at the beginning of a text is considered as
* a title and not output. */
if( blob_size(ob)<=PROLOG_SIZE && title!=0 && blob_size(title)==0 ){
BLOB_APPEND_BLOB(title, text);
return;
}
INTER_BLOCK(ob);
blob_appendf(ob, "<h%d>", level);
BLOB_APPEND_BLOB(ob, text);
blob_appendf(ob, "</h%d>", level);
}
static void html_hrule(struct Blob *ob, void *opaque){
INTER_BLOCK(ob);
BLOB_APPEND_LITERAL(ob, "<hr />\n");
}
static void html_list(
struct Blob *ob,
struct Blob *text,
int flags,
void *opaque
){
char ol[] = "ol";
char ul[] = "ul";
char *tag = (flags & MKD_LIST_ORDERED) ? ol : ul;
INTER_BLOCK(ob);
blob_appendf(ob, "<%s>\n", tag);
BLOB_APPEND_BLOB(ob, text);
blob_appendf(ob, "</%s>\n", tag);
}
static void html_list_item(
struct Blob *ob,
struct Blob *text,
int flags,
void *opaque
){
char *text_data = blob_buffer(text);
size_t text_size = blob_size(text);
while( text_size>0 && text_data[text_size-1]=='\n' ) text_size--;
BLOB_APPEND_LITERAL(ob, "<li>");
blob_append(ob, text_data, text_size);
BLOB_APPEND_LITERAL(ob, "</li>\n");
}
static void html_paragraph(struct Blob *ob, struct Blob *text, void *opaque){
INTER_BLOCK(ob);
BLOB_APPEND_LITERAL(ob, "<p>");
BLOB_APPEND_BLOB(ob, text);
BLOB_APPEND_LITERAL(ob, "</p>\n");
}
static void html_table(
struct Blob *ob,
struct Blob *head_row,
struct Blob *rows,
void *opaque
){
INTER_BLOCK(ob);
BLOB_APPEND_LITERAL(ob, "<table>\n");
if( head_row && blob_size(head_row)>0 ){
BLOB_APPEND_LITERAL(ob, "<thead>\n");
BLOB_APPEND_BLOB(ob, head_row);
BLOB_APPEND_LITERAL(ob, "</thead>\n<tbody>\n");
}
if( rows ){
BLOB_APPEND_BLOB(ob, rows);
}
if( head_row && blob_size(head_row)>0 ){
BLOB_APPEND_LITERAL(ob, "</tbody>\n");
}
BLOB_APPEND_LITERAL(ob, "</table>\n");
}
static void html_table_cell(
struct Blob *ob,
struct Blob *text,
int flags,
void *opaque
){
if( flags & MKD_CELL_HEAD ){
BLOB_APPEND_LITERAL(ob, " <th");
}else{
BLOB_APPEND_LITERAL(ob, " <td");
}
switch( flags & MKD_CELL_ALIGN_MASK ){
case MKD_CELL_ALIGN_LEFT: {
BLOB_APPEND_LITERAL(ob, " align=\"left\"");
break;
}
case MKD_CELL_ALIGN_RIGHT: {
BLOB_APPEND_LITERAL(ob, " align=\"right\"");
break;
}
case MKD_CELL_ALIGN_CENTER: {
BLOB_APPEND_LITERAL(ob, " align=\"center\"");
break;
}
}
BLOB_APPEND_LITERAL(ob, ">");
BLOB_APPEND_BLOB(ob, text);
if( flags & MKD_CELL_HEAD ){
BLOB_APPEND_LITERAL(ob, "</th>\n");
}else{
BLOB_APPEND_LITERAL(ob, "</td>\n");
}
}
static void html_table_row(
struct Blob *ob,
struct Blob *cells,
int flags,
void *opaque
){
BLOB_APPEND_LITERAL(ob, " <tr>\n");
BLOB_APPEND_BLOB(ob, cells);
BLOB_APPEND_LITERAL(ob, " </tr>\n");
}
/* HTML span tags */
static int html_raw_html_tag(struct Blob *ob, struct Blob *text, void *opaque){
blob_append(ob, blob_buffer(text), blob_size(text));
return 1;
}
static int html_autolink(
struct Blob *ob,
struct Blob *link,
enum mkd_autolink type,
void *opaque
){
if( !link || blob_size(link)<=0 ) return 0;
BLOB_APPEND_LITERAL(ob, "<a href=\"");
if( type==MKDA_IMPLICIT_EMAIL ) BLOB_APPEND_LITERAL(ob, "mailto:");
html_quote(ob, blob_buffer(link), blob_size(link));
BLOB_APPEND_LITERAL(ob, "\">");
if( type==MKDA_EXPLICIT_EMAIL && blob_size(link)>7 ){
/* remove "mailto:" from displayed text */
html_escape(ob, blob_buffer(link)+7, blob_size(link)-7);
}else{
html_escape(ob, blob_buffer(link), blob_size(link));
}
BLOB_APPEND_LITERAL(ob, "</a>");
return 1;
}
/*
** The nSrc bytes at zSrc[] are Pikchr input text (allegedly). Process that
** text and insert the result in place of the original.
*/
void pikchr_to_html(
Blob *ob, /* Write the generated SVG here */
const char *zSrc, int nSrc, /* The Pikchr source text */
const char *zArg, int nArg /* Addition arguments */
){
int pikFlags = PIKCHR_PROCESS_NONCE
| PIKCHR_PROCESS_DIV
| PIKCHR_PROCESS_SRC
| PIKCHR_PROCESS_ERR_PRE;
Blob bSrc = empty_blob;
const char *zPikVar;
double rPikVar;
while( nArg>0 ){
int i;
for(i=0; i<nArg && !fossil_isspace(zArg[i]); i++){}
if( i==6 && strncmp(zArg, "center", 6)==0 ){
pikFlags |= PIKCHR_PROCESS_DIV_CENTER;
}else if( i==6 && strncmp(zArg, "indent", 6)==0 ){
pikFlags |= PIKCHR_PROCESS_DIV_INDENT;
}else if( i==10 && strncmp(zArg, "float-left", 10)==0 ){
pikFlags |= PIKCHR_PROCESS_DIV_FLOAT_LEFT;
}else if( i==11 && strncmp(zArg, "float-right", 11)==0 ){
pikFlags |= PIKCHR_PROCESS_DIV_FLOAT_RIGHT;
}else if( i==6 && strncmp(zArg, "toggle", 6)==0 ){
pikFlags |= PIKCHR_PROCESS_DIV_TOGGLE;
}else if( i==6 && strncmp(zArg, "source", 6)==0 ){
pikFlags |= PIKCHR_PROCESS_DIV_SOURCE;
}else if( i==13 && strncmp(zArg, "source-inline", 13)==0 ){
pikFlags |= PIKCHR_PROCESS_DIV_SOURCE_INLINE;
}
while( i<nArg && fossil_isspace(zArg[i]) ){ i++; }
zArg += i;
nArg -= i;
}
if( skin_detail_boolean("white-foreground") ){
pikFlags |= 0x02; /* PIKCHR_DARK_MODE */
}
zPikVar = skin_detail("pikchr-foreground");
if( zPikVar && zPikVar[0] ){
blob_appendf(&bSrc, "fgcolor = %s\n", zPikVar);
}
zPikVar = skin_detail("pikchr-background");
if( zPikVar && zPikVar[0] ){
blob_appendf(&bSrc, "bgcolor = %s\n", zPikVar);
}
zPikVar = skin_detail("pikchr-scale");
if( zPikVar
&& (rPikVar = atof(zPikVar))>=0.1
&& rPikVar<10.0
){
blob_appendf(&bSrc, "scale = %.13g\n", rPikVar);
}
zPikVar = skin_detail("pikchr-fontscale");
if( zPikVar
&& (rPikVar = atof(zPikVar))>=0.1
&& rPikVar<10.0
){
blob_appendf(&bSrc, "fontscale = %.13g\n", rPikVar);
}
blob_append(&bSrc, zSrc, nSrc)
/*have to dup input to ensure a NUL-terminated source string */;
pikchr_process(blob_str(&bSrc), pikFlags, 0, ob);
blob_reset(&bSrc);
}
/* Invoked for `...` blocks where there are nSep grave accents in a
** row that serve as the delimiter. According to CommonMark:
**
** * https://spec.commonmark.org/0.29/#fenced-code-blocks
** * https://spec.commonmark.org/0.29/#code-spans
**
** If nSep is 1 or 2, then this is a code-span which is inline.
** If nSep is 3 or more, then this is a fenced code block
*/
static int html_codespan(
struct Blob *ob, /* Write the output here */
struct Blob *text, /* The stuff in between the code span marks */
int nSep, /* Number of grave accents marks as delimiters */
void *opaque
){
if( text==0 ){
/* no-op */
}else if( nSep<=2 ){
/* One or two graves: an in-line code span */
BLOB_APPEND_LITERAL(ob, "<code>");
html_escape(ob, blob_buffer(text), blob_size(text));
BLOB_APPEND_LITERAL(ob, "</code>");
}else{
/* Three or more graves: a fenced code block */
int n = blob_size(text);
const char *z = blob_buffer(text);
int i;
for(i=0; i<n && z[i]!='\n'; i++){}
if( i>=n ){
blob_appendf(ob, "<pre><code>%#h</code></pre>", n, z);
}else{
int k, j;
i++;
for(k=0; k<i && fossil_isspace(z[k]); k++){}
if( k==i ){
blob_appendf(ob, "<pre><code>%#h</code></pre>", n-i, z+i);
}else{
for(j=k+1; j<i && !fossil_isspace(z[j]); j++){}
if( j-k==6 && strncmp(z+k,"pikchr",6)==0 ){
while( j<i && fossil_isspace(z[j]) ){ j++; }
pikchr_to_html(ob, z+i, n-i, z+j, i-j);
}else{
blob_appendf(ob, "<pre><code class='language-%#h'>%#h</code></pre>",
j-k, z+k, n-i, z+i);
}
}
}
}
return 1;
}
static int html_double_emphasis(
struct Blob *ob,
struct Blob *text,
char c,
void *opaque
){
BLOB_APPEND_LITERAL(ob, "<strong>");
BLOB_APPEND_BLOB(ob, text);
BLOB_APPEND_LITERAL(ob, "</strong>");
return 1;
}
static int html_emphasis(
struct Blob *ob,
struct Blob *text,
char c,
void *opaque
){
BLOB_APPEND_LITERAL(ob, "<em>");
BLOB_APPEND_BLOB(ob, text);
BLOB_APPEND_LITERAL(ob, "</em>");
return 1;
}
static int html_image(
struct Blob *ob,
struct Blob *link,
struct Blob *title,
struct Blob *alt,
void *opaque
){
BLOB_APPEND_LITERAL(ob, "<img src=\"");
html_quote(ob, blob_buffer(link), blob_size(link));
BLOB_APPEND_LITERAL(ob, "\" alt=\"");
html_quote(ob, blob_buffer(alt), blob_size(alt));
if( title && blob_size(title)>0 ){
BLOB_APPEND_LITERAL(ob, "\" title=\"");
html_quote(ob, blob_buffer(title), blob_size(title));
}
BLOB_APPEND_LITERAL(ob, "\" />");
return 1;
}
static int html_linebreak(struct Blob *ob, void *opaque){
BLOB_APPEND_LITERAL(ob, "<br />\n");
return 1;
}
static int html_link(
struct Blob *ob,
struct Blob *link,
struct Blob *title,
struct Blob *content,
void *opaque
){
char *zLink = blob_buffer(link);
char *zTitle = title!=0 && blob_size(title)>0 ? blob_str(title) : 0;
char zClose[20];
if( zLink==0 || zLink[0]==0 ){
zClose[0] = 0;
}else{
static const int flags =
WIKI_NOBADLINKS |
WIKI_MARKDOWNLINKS
;
wiki_resolve_hyperlink(ob, flags, zLink, zClose, sizeof(zClose), 0, zTitle);
}
if( blob_size(content)==0 ){
if( link ) BLOB_APPEND_BLOB(ob, link);
}else{
BLOB_APPEND_BLOB(ob, content);
}
blob_append(ob, zClose, -1);
return 1;
}
static int html_triple_emphasis(
struct Blob *ob,
struct Blob *text,
char c,
void *opaque
){
BLOB_APPEND_LITERAL(ob, "<strong><em>");
BLOB_APPEND_BLOB(ob, text);
BLOB_APPEND_LITERAL(ob, "</em></strong>");
return 1;
}
static void html_normal_text(struct Blob *ob, struct Blob *text, void *opaque){
html_escape(ob, blob_buffer(text), blob_size(text));
}
/*
** Convert markdown into HTML.
**
** The document title is placed in output_title if not NULL. Or if
** output_title is NULL, the document title appears in the body.
*/
void markdown_to_html(
struct Blob *input_markdown, /* Markdown content to be rendered */
struct Blob *output_title, /* Put title here. May be NULL */
struct Blob *output_body /* Put document body here. */
){
struct mkd_renderer html_renderer = {
/* prolog and epilog */
html_prolog,
html_epilog,
/* block level elements */
html_blockcode,
html_blockquote,
html_blockhtml,
html_header,
html_hrule,
html_list,
html_list_item,
html_paragraph,
html_table,
html_table_cell,
html_table_row,
/* span level elements */
html_autolink,
html_codespan,
html_double_emphasis,
html_emphasis,
html_image,
html_linebreak,
html_link,
html_raw_html_tag,
html_triple_emphasis,
/* low level elements */
0, /* entity */
html_normal_text,
/* misc. parameters */
"*_", /* emph_chars */
0 /* opaque */
};
MarkdownToHtml context;
memset(&context, 0, sizeof(context));
context.output_title = output_title;
html_renderer.opaque = &context;
if( output_title ) blob_reset(output_title);
blob_reset(output_body);
markdown(output_body, input_markdown, &html_renderer);
}