libcmd/markdown: handle allocation errors in lowdown_term_rndr

We upgrade to lowdown 0.8.0 [1] which contains a fix/improvement to a
behavior mentioned in this issue thread [2] where a big part of
lowdown's API would just call exit(1) on allocation errors since that
is a satisfying behavior for the lowdown binary.

Now lowdown_term_rndr returns 0 if an allocation error occurred which we
check for in libcmd/markdown.cc.

Also the extern "C" { } wrapper around lowdown.h has been removed as it
is not necessary.

[1]: 6ca7c855a0/versions.xml (L987-L1006)
[2]: https://github.com/kristapsdz/lowdown/issues/45#issuecomment-756681153
This commit is contained in:
sternenseemann 2021-02-06 12:59:11 +01:00
parent 480426a364
commit d0e34c85f8
2 changed files with 7 additions and 7 deletions

View file

@ -198,12 +198,12 @@
};
lowdown = with final; stdenv.mkDerivation {
name = "lowdown-0.7.9";
lowdown = with final; stdenv.mkDerivation rec {
name = "lowdown-0.8.0";
src = fetchurl {
url = https://kristaps.bsd.lv/lowdown/snapshots/lowdown-0.7.9.tar.gz;
hash = "sha512-7GQrKFICyTI5T4SinATfohiCq9TC0OgN8NmVfG3B3BZJM9J00DT8llAco8kNykLIKtl/AXuS4X8fETiCFEWEUQ==";
url = "https://kristaps.bsd.lv/lowdown/snapshots/${name}.tar.gz";
hash = "sha512-U9WeGoInT9vrawwa57t6u9dEdRge4/P+0wLxmQyOL9nhzOEUU2FRz2Be9H0dCjYE7p2v3vCXIYk40M+jjULATw==";
};
#src = lowdown-src;

View file

@ -3,9 +3,7 @@
#include "finally.hh"
#include <sys/queue.h>
extern "C" {
#include <lowdown.h>
}
namespace nix {
@ -42,7 +40,9 @@ std::string renderMarkdownToTerminal(std::string_view markdown)
throw Error("cannot allocate Markdown output buffer");
Finally freeBuffer([&]() { lowdown_buf_free(buf); });
lowdown_term_rndr(buf, nullptr, renderer, node);
int rndr_res = lowdown_term_rndr(buf, nullptr, renderer, node);
if (!rndr_res)
throw Error("allocation error while rendering Markdown");
return std::string(buf->data, buf->size);
}