Nix/src/libcmd/markdown.cc

60 lines
1.6 KiB
C++

#include "markdown.hh"
#include "util.hh"
#include "finally.hh"
#include "terminal.hh"
#include <sys/queue.h>
#if HAVE_LOWDOWN
#include <lowdown.h>
#endif
namespace nix {
std::string renderMarkdownToTerminal(std::string_view markdown)
{
#if HAVE_LOWDOWN
int windowWidth = getWindowSize().second;
struct lowdown_opts opts {
.type = LOWDOWN_TERM,
.maxdepth = 20,
.cols = (size_t) std::max(windowWidth - 5, 60),
.hmargin = 0,
.vmargin = 0,
.feat = LOWDOWN_COMMONMARK | LOWDOWN_FENCED | LOWDOWN_DEFLIST | LOWDOWN_TABLES,
.oflags = LOWDOWN_TERM_NOLINK,
};
auto doc = lowdown_doc_new(&opts);
if (!doc)
throw Error("cannot allocate Markdown document");
Finally freeDoc([&]() { lowdown_doc_free(doc); });
size_t maxn = 0;
auto node = lowdown_doc_parse(doc, &maxn, markdown.data(), markdown.size(), nullptr);
if (!node)
throw Error("cannot parse Markdown document");
Finally freeNode([&]() { lowdown_node_free(node); });
auto renderer = lowdown_term_new(&opts);
if (!renderer)
throw Error("cannot allocate Markdown renderer");
Finally freeRenderer([&]() { lowdown_term_free(renderer); });
auto buf = lowdown_buf_new(16384);
if (!buf)
throw Error("cannot allocate Markdown output buffer");
Finally freeBuffer([&]() { lowdown_buf_free(buf); });
int rndr_res = lowdown_term_rndr(buf, renderer, node);
if (!rndr_res)
throw Error("allocation error while rendering Markdown");
return filterANSIEscapes(std::string(buf->data, buf->size), !shouldANSI());
#else
return std::string(markdown);
#endif
}
}