ctai/3rdparty/cmark-gfm/src/html.c
2025-03-07 14:53:40 +08:00

503 lines
15 KiB
C

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "cmark_ctype.h"
#include "config.h"
#include "cmark-gfm.h"
#include "houdini.h"
#include "scanners.h"
#include "syntax_extension.h"
#include "html.h"
#include "render.h"
// Functions to convert cmark_nodes to HTML strings.
static void escape_html(cmark_strbuf *dest, const unsigned char *source,
bufsize_t length) {
houdini_escape_html0(dest, source, length, 0);
}
static void filter_html_block(cmark_html_renderer *renderer, uint8_t *data, size_t len) {
cmark_strbuf *html = renderer->html;
cmark_llist *it;
cmark_syntax_extension *ext;
bool filtered;
uint8_t *match;
while (len) {
match = (uint8_t *) memchr(data, '<', len);
if (!match)
break;
if (match != data) {
cmark_strbuf_put(html, data, (bufsize_t)(match - data));
len -= (match - data);
data = match;
}
filtered = false;
for (it = renderer->filter_extensions; it; it = it->next) {
ext = ((cmark_syntax_extension *) it->data);
if (!ext->html_filter_func(ext, data, len)) {
filtered = true;
break;
}
}
if (!filtered) {
cmark_strbuf_putc(html, '<');
} else {
cmark_strbuf_puts(html, "&lt;");
}
++data;
--len;
}
if (len)
cmark_strbuf_put(html, data, (bufsize_t)len);
}
static bool S_put_footnote_backref(cmark_html_renderer *renderer, cmark_strbuf *html, cmark_node *node) {
if (renderer->written_footnote_ix >= renderer->footnote_ix)
return false;
renderer->written_footnote_ix = renderer->footnote_ix;
char m[32];
snprintf(m, sizeof(m), "%d", renderer->written_footnote_ix);
cmark_strbuf_puts(html, "<a href=\"#fnref-");
houdini_escape_href(html, node->as.literal.data, node->as.literal.len);
cmark_strbuf_puts(html, "\" class=\"footnote-backref\" data-footnote-backref data-footnote-backref-idx=\"");
cmark_strbuf_puts(html, m);
cmark_strbuf_puts(html, "\" aria-label=\"Back to reference ");
cmark_strbuf_puts(html, m);
cmark_strbuf_puts(html, "\">↩</a>");
if (node->footnote.def_count > 1)
{
for(int i = 2; i <= node->footnote.def_count; i++) {
char n[32];
snprintf(n, sizeof(n), "%d", i);
cmark_strbuf_puts(html, " <a href=\"#fnref-");
houdini_escape_href(html, node->as.literal.data, node->as.literal.len);
cmark_strbuf_puts(html, "-");
cmark_strbuf_puts(html, n);
cmark_strbuf_puts(html, "\" class=\"footnote-backref\" data-footnote-backref data-footnote-backref-idx=\"");
cmark_strbuf_puts(html, m);
cmark_strbuf_puts(html, "-");
cmark_strbuf_puts(html, n);
cmark_strbuf_puts(html, "\" aria-label=\"Back to reference ");
cmark_strbuf_puts(html, m);
cmark_strbuf_puts(html, "-");
cmark_strbuf_puts(html, n);
cmark_strbuf_puts(html, "\">↩<sup class=\"footnote-ref\">");
cmark_strbuf_puts(html, n);
cmark_strbuf_puts(html, "</sup></a>");
}
}
return true;
}
static int S_render_node(cmark_html_renderer *renderer, cmark_node *node,
cmark_event_type ev_type, int options) {
cmark_node *parent;
cmark_node *grandparent;
cmark_strbuf *html = renderer->html;
cmark_llist *it;
cmark_syntax_extension *ext;
char start_heading[] = "<h0";
char end_heading[] = "</h0";
bool tight;
bool filtered;
char buffer[BUFFER_SIZE];
bool entering = (ev_type == CMARK_EVENT_ENTER);
if (renderer->plain == node) { // back at original node
renderer->plain = NULL;
}
if (renderer->plain != NULL) {
switch (node->type) {
case CMARK_NODE_TEXT:
case CMARK_NODE_CODE:
case CMARK_NODE_HTML_INLINE:
escape_html(html, node->as.literal.data, node->as.literal.len);
break;
case CMARK_NODE_LINEBREAK:
case CMARK_NODE_SOFTBREAK:
cmark_strbuf_putc(html, ' ');
break;
default:
break;
}
return 1;
}
if (node->extension && node->extension->html_render_func) {
node->extension->html_render_func(node->extension, renderer, node, ev_type, options);
return 1;
}
switch (node->type) {
case CMARK_NODE_DOCUMENT:
break;
case CMARK_NODE_BLOCK_QUOTE:
if (entering) {
cmark_html_render_cr(html);
cmark_strbuf_puts(html, "<blockquote");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, ">\n");
} else {
cmark_html_render_cr(html);
cmark_strbuf_puts(html, "</blockquote>\n");
}
break;
case CMARK_NODE_LIST: {
cmark_list_type list_type = node->as.list.list_type;
int start = node->as.list.start;
if (entering) {
cmark_html_render_cr(html);
if (list_type == CMARK_BULLET_LIST) {
cmark_strbuf_puts(html, "<ul");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, ">\n");
} else if (start == 1) {
cmark_strbuf_puts(html, "<ol");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, ">\n");
} else {
snprintf(buffer, BUFFER_SIZE, "<ol start=\"%d\"", start);
cmark_strbuf_puts(html, buffer);
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, ">\n");
}
} else {
cmark_strbuf_puts(html,
list_type == CMARK_BULLET_LIST ? "</ul>\n" : "</ol>\n");
}
break;
}
case CMARK_NODE_ITEM:
if (entering) {
cmark_html_render_cr(html);
cmark_strbuf_puts(html, "<li");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_putc(html, '>');
} else {
cmark_strbuf_puts(html, "</li>\n");
}
break;
case CMARK_NODE_HEADING:
if (entering) {
cmark_html_render_cr(html);
start_heading[2] = (char)('0' + node->as.heading.level);
cmark_strbuf_puts(html, start_heading);
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_putc(html, '>');
} else {
end_heading[3] = (char)('0' + node->as.heading.level);
cmark_strbuf_puts(html, end_heading);
cmark_strbuf_puts(html, ">\n");
}
break;
case CMARK_NODE_CODE_BLOCK:
cmark_html_render_cr(html);
if (node->as.code.info.len == 0) {
cmark_strbuf_puts(html, "<pre");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, "><code>");
} else {
bufsize_t first_tag = 0;
while (first_tag < node->as.code.info.len &&
!cmark_isspace(node->as.code.info.data[first_tag])) {
first_tag += 1;
}
if (options & CMARK_OPT_GITHUB_PRE_LANG) {
cmark_strbuf_puts(html, "<pre");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, " lang=\"");
escape_html(html, node->as.code.info.data, first_tag);
if (first_tag < node->as.code.info.len && (options & CMARK_OPT_FULL_INFO_STRING)) {
cmark_strbuf_puts(html, "\" data-meta=\"");
escape_html(html, node->as.code.info.data + first_tag + 1, node->as.code.info.len - first_tag - 1);
}
cmark_strbuf_puts(html, "\"><code>");
} else {
cmark_strbuf_puts(html, "<pre");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, "><code class=\"language-");
escape_html(html, node->as.code.info.data, first_tag);
if (first_tag < node->as.code.info.len && (options & CMARK_OPT_FULL_INFO_STRING)) {
cmark_strbuf_puts(html, "\" data-meta=\"");
escape_html(html, node->as.code.info.data + first_tag + 1, node->as.code.info.len - first_tag - 1);
}
cmark_strbuf_puts(html, "\">");
}
}
escape_html(html, node->as.code.literal.data, node->as.code.literal.len);
cmark_strbuf_puts(html, "</code></pre>\n");
break;
case CMARK_NODE_HTML_BLOCK:
cmark_html_render_cr(html);
if (!(options & CMARK_OPT_UNSAFE)) {
cmark_strbuf_puts(html, "<!-- raw HTML omitted -->");
} else if (renderer->filter_extensions) {
filter_html_block(renderer, node->as.literal.data, node->as.literal.len);
} else {
cmark_strbuf_put(html, node->as.literal.data, node->as.literal.len);
}
cmark_html_render_cr(html);
break;
case CMARK_NODE_CUSTOM_BLOCK:
cmark_html_render_cr(html);
if (entering) {
cmark_strbuf_put(html, node->as.custom.on_enter.data,
node->as.custom.on_enter.len);
} else {
cmark_strbuf_put(html, node->as.custom.on_exit.data,
node->as.custom.on_exit.len);
}
cmark_html_render_cr(html);
break;
case CMARK_NODE_THEMATIC_BREAK:
cmark_html_render_cr(html);
cmark_strbuf_puts(html, "<hr");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_puts(html, " />\n");
break;
case CMARK_NODE_PARAGRAPH:
parent = cmark_node_parent(node);
grandparent = cmark_node_parent(parent);
if (grandparent != NULL && grandparent->type == CMARK_NODE_LIST) {
tight = grandparent->as.list.tight;
} else {
tight = false;
}
if (!tight) {
if (entering) {
cmark_html_render_cr(html);
cmark_strbuf_puts(html, "<p");
cmark_html_render_sourcepos(node, html, options);
cmark_strbuf_putc(html, '>');
} else {
if (parent->type == CMARK_NODE_FOOTNOTE_DEFINITION && node->next == NULL) {
cmark_strbuf_putc(html, ' ');
S_put_footnote_backref(renderer, html, parent);
}
cmark_strbuf_puts(html, "</p>\n");
}
}
break;
case CMARK_NODE_TEXT:
escape_html(html, node->as.literal.data, node->as.literal.len);
break;
case CMARK_NODE_LINEBREAK:
cmark_strbuf_puts(html, "<br />\n");
break;
case CMARK_NODE_SOFTBREAK:
if (options & CMARK_OPT_HARDBREAKS) {
cmark_strbuf_puts(html, "<br />\n");
} else if (options & CMARK_OPT_NOBREAKS) {
cmark_strbuf_putc(html, ' ');
} else {
cmark_strbuf_putc(html, '\n');
}
break;
case CMARK_NODE_CODE:
cmark_strbuf_puts(html, "<code>");
escape_html(html, node->as.literal.data, node->as.literal.len);
cmark_strbuf_puts(html, "</code>");
break;
case CMARK_NODE_HTML_INLINE:
if (!(options & CMARK_OPT_UNSAFE)) {
cmark_strbuf_puts(html, "<!-- raw HTML omitted -->");
} else {
filtered = false;
for (it = renderer->filter_extensions; it; it = it->next) {
ext = (cmark_syntax_extension *) it->data;
if (!ext->html_filter_func(ext, node->as.literal.data, node->as.literal.len)) {
filtered = true;
break;
}
}
if (!filtered) {
cmark_strbuf_put(html, node->as.literal.data, node->as.literal.len);
} else {
cmark_strbuf_puts(html, "&lt;");
cmark_strbuf_put(html, node->as.literal.data + 1, node->as.literal.len - 1);
}
}
break;
case CMARK_NODE_CUSTOM_INLINE:
if (entering) {
cmark_strbuf_put(html, node->as.custom.on_enter.data,
node->as.custom.on_enter.len);
} else {
cmark_strbuf_put(html, node->as.custom.on_exit.data,
node->as.custom.on_exit.len);
}
break;
case CMARK_NODE_STRONG:
if (node->parent == NULL || node->parent->type != CMARK_NODE_STRONG) {
if (entering) {
cmark_strbuf_puts(html, "<strong>");
} else {
cmark_strbuf_puts(html, "</strong>");
}
}
break;
case CMARK_NODE_EMPH:
if (entering) {
cmark_strbuf_puts(html, "<em>");
} else {
cmark_strbuf_puts(html, "</em>");
}
break;
case CMARK_NODE_LINK:
if (entering) {
cmark_strbuf_puts(html, "<a href=\"");
if ((options & CMARK_OPT_UNSAFE) ||
!(scan_dangerous_url(&node->as.link.url, 0))) {
houdini_escape_href(html, node->as.link.url.data,
node->as.link.url.len);
}
if (node->as.link.title.len) {
cmark_strbuf_puts(html, "\" title=\"");
escape_html(html, node->as.link.title.data, node->as.link.title.len);
}
cmark_strbuf_puts(html, "\">");
} else {
cmark_strbuf_puts(html, "</a>");
}
break;
case CMARK_NODE_IMAGE:
if (entering) {
cmark_strbuf_puts(html, "<img src=\"");
if ((options & CMARK_OPT_UNSAFE) ||
!(scan_dangerous_url(&node->as.link.url, 0))) {
houdini_escape_href(html, node->as.link.url.data,
node->as.link.url.len);
}
cmark_strbuf_puts(html, "\" alt=\"");
renderer->plain = node;
} else {
if (node->as.link.title.len) {
cmark_strbuf_puts(html, "\" title=\"");
escape_html(html, node->as.link.title.data, node->as.link.title.len);
}
cmark_strbuf_puts(html, "\" />");
}
break;
case CMARK_NODE_FOOTNOTE_DEFINITION:
if (entering) {
if (renderer->footnote_ix == 0) {
cmark_strbuf_puts(html, "<section class=\"footnotes\" data-footnotes>\n<ol>\n");
}
++renderer->footnote_ix;
cmark_strbuf_puts(html, "<li id=\"fn-");
houdini_escape_href(html, node->as.literal.data, node->as.literal.len);
cmark_strbuf_puts(html, "\">\n");
} else {
if (S_put_footnote_backref(renderer, html, node)) {
cmark_strbuf_putc(html, '\n');
}
cmark_strbuf_puts(html, "</li>\n");
}
break;
case CMARK_NODE_FOOTNOTE_REFERENCE:
if (entering) {
cmark_strbuf_puts(html, "<sup class=\"footnote-ref\"><a href=\"#fn-");
houdini_escape_href(html, node->parent_footnote_def->as.literal.data, node->parent_footnote_def->as.literal.len);
cmark_strbuf_puts(html, "\" id=\"fnref-");
houdini_escape_href(html, node->parent_footnote_def->as.literal.data, node->parent_footnote_def->as.literal.len);
if (node->footnote.ref_ix > 1) {
char n[32];
snprintf(n, sizeof(n), "%d", node->footnote.ref_ix);
cmark_strbuf_puts(html, "-");
cmark_strbuf_puts(html, n);
}
cmark_strbuf_puts(html, "\" data-footnote-ref>");
houdini_escape_href(html, node->as.literal.data, node->as.literal.len);
cmark_strbuf_puts(html, "</a></sup>");
}
break;
default:
assert(false);
break;
}
return 1;
}
char *cmark_render_html(cmark_node *root, int options, cmark_llist *extensions) {
return cmark_render_html_with_mem(root, options, extensions, cmark_node_mem(root));
}
char *cmark_render_html_with_mem(cmark_node *root, int options, cmark_llist *extensions, cmark_mem *mem) {
char *result;
cmark_strbuf html = CMARK_BUF_INIT(mem);
cmark_event_type ev_type;
cmark_node *cur;
cmark_html_renderer renderer = {&html, NULL, NULL, 0, 0, NULL};
cmark_iter *iter = cmark_iter_new(root);
for (; extensions; extensions = extensions->next)
if (((cmark_syntax_extension *) extensions->data)->html_filter_func)
renderer.filter_extensions = cmark_llist_append(
mem,
renderer.filter_extensions,
(cmark_syntax_extension *) extensions->data);
while ((ev_type = cmark_iter_next(iter)) != CMARK_EVENT_DONE) {
cur = cmark_iter_get_node(iter);
S_render_node(&renderer, cur, ev_type, options);
}
if (renderer.footnote_ix) {
cmark_strbuf_puts(&html, "</ol>\n</section>\n");
}
result = (char *)cmark_strbuf_detach(&html);
cmark_llist_free(mem, renderer.filter_extensions);
cmark_iter_free(iter);
return result;
}