path: root/src/cmark.c

#include <stdlib.h>
#include <assert.h>
#include <stdio.h>
#include "references.h"
#include "html/houdini.h"
#include "cmark.h"
#include "buffer.h"
#include "ast.h"

// AST traversal and manipulation functions

cmark_node_block *cmark_block_next(cmark_node_block *current)
{
    return current->next;
}

cmark_node_block *cmark_block_previous(cmark_node_block *current)
{
    return current->prev;
}

cmark_node_block *cmark_block_parent(cmark_node_block *current)
{
    return current->parent;
}

cmark_node_block *cmark_block_children(cmark_node_block *current)
{
    return current->children;
}

void cmark_block_delete(cmark_node_block *current)
{
    if (current->prev) {
        current->prev->next = current->next;
    }
    if (current->next) {
        current->next->prev = current->prev;
    }
    current->next = NULL;
    cmark_free_blocks(current);
}

void cmark_block_insert_before(cmark_node_block *new, cmark_node_block *current)
{
    // Find last node in new:
    cmark_node_block *new_last = new;
    while (new_last->next) {
        new_last = new_last->next;
    }
    new_last->next = current;
    current->prev = new_last;
    if (current->prev) {
        current->prev->next = new;
        new->prev = current->prev;
    }
}

void cmark_block_insert_after(cmark_node_block *current, cmark_node_block *new)
{
    // Find last node in new:
    cmark_node_block *new_last = new;
    while (new_last->next) {
        new_last = new_last->next;
    }
    if (current->next) {
        new_last->next = current->next;
        current->next->prev = new_last;
    }
    current->next = new;
    new->prev = current;
}

/* * */

unsigned char *cmark_markdown_to_html(unsigned char *text, int len)
{
    node_block *blocks;
    unsigned char *result;

    blocks = cmark_parse_document(text, len);

    result = cmark_render_html(blocks);
    cmark_free_blocks(blocks);

    return result;
}

// Utility function used by free_inlines
static void splice_into_list(cmark_node_inl* e, node_inl* children) {
    cmark_node_inl * tmp;
    if (children) {
        tmp = children;
        // Find last child
        while (tmp->next) {
            tmp = tmp->next;
        }
        // Splice children into list
        tmp->next = e->next;
        e->next = children;
    }
    return ;
}

// Free an inline list.  Avoid recursion to prevent stack overflows
// on deeply nested structures.
void cmark_free_inlines(cmark_node_inl* e)
{
    node_inl * next;

    while (e != NULL) {
        switch (e->tag){
        case CMARK_INL_STRING:
        case CMARK_INL_RAW_HTML:
        case CMARK_INL_CODE:
            cmark_chunk_free(&e->content.literal);
            break;
        case CMARK_INL_LINEBREAK:
        case CMARK_INL_SOFTBREAK:
            break;
        case CMARK_INL_LINK:
        case CMARK_INL_IMAGE:
            free(e->content.linkable.url);
            free(e->content.linkable.title);
            splice_into_list(e, e->content.linkable.label);
            break;
        case CMARK_INL_EMPH:
        case CMARK_INL_STRONG:
                splice_into_list(e, e->content.inlines);
            break;
        default:
                fprintf(stderr, "[WARN] (%s:%d) Unknown inline tag %d",
                __FILE__, __LINE__, e->tag);
            break;
        }
        next = e->next;
        free(e);
        e = next;
    }
}

unsigned char *cmark_clean_autolink(chunk *url, int is_email)
{
    strbuf buf = GH_BUF_INIT;

    chunk_trim(url);

    if (url->len == 0)
        return NULL;

    if (is_email)
        strbuf_puts(&buf, "mailto:");

    houdini_unescape_html_f(&buf, url->data, url->len);
    return strbuf_detach(&buf);
}

// Free a node_block list and any children.
void cmark_free_blocks(cmark_node_block *e)
{
    cmark_node_block * next;
    while (e != NULL) {
        cmark_free_inlines(e->inline_content);
        strbuf_free(&e->string_content);
        if (e->tag == CMARK_BLOCK_FENCED_CODE) {
            strbuf_free(&e->as.code.info);
        }
        if (e->last_child) {
            // Splice children into list
            e->last_child->next = e->next;
            e->next = e->children;
        }
        next = e->next;
        free(e);
        e = next;
    }
}