LOWDOWN_BUF(3) Library Functions Manual LOWDOWN_BUF(3)

lowdown_bufparse a Markdown buffer into formatted output

library “liblowdown”

#include <sys/queue.h>
#include <stdio.h>
#include <lowdown.h>

int
lowdown_buf(const struct lowdown_opts *opts, const char *buf, size_t bufsz, char **ret, size_t *retsz, struct lowdown_metaq *metaq);

Parses a lowdown(5) buffer buf of size bufsz into an output buffer ret of size retsz according to a configuration opts. The output format is specified by opts->type. If LOWDOWN_METADATA is set in opts->feat and metaq is not NULL, metaq is filled with metadata rendered in the given output format.

The caller is responsible for freeing ret and metaq.

Returns zero on failure, non-zero on success. On failure, the values pointed to by res and rsz are undefined.

The following parses standard input into a standalone HTML5 document. It enables footnotes, autolinks, tables, superscript, strikethrough, fenced codeblocks, commonmark, definition lists, extended image attributes, and metadata processing. The output passes through raw HTML and has smart typography.

struct lowdown_opts opts;
char *buf = NULL, *obuf;
char rbuf[1024];
size_t sz, bufsz = 0, obufsz;

while (!(feof(stdin) || ferror(stdin))) {
  sz = fread(rbuf, 1, sizeof(rbuf), stdin);
  if (sz == 0)
    err(1, "fread");
  buf = realloc(buf, bufsz + sz);
  if (buf == NULL)
    err(1, NULL);
  memcpy(buf + bufsz, rbuf, sz);
  bufsz += sz;
}

if (ferror(stdin))
  err(1, "fread");

memset(&opts, 0, sizeof(struct lowdown_opts));
opts.type = LOWDOWN_HTML;
opts.feat = LOWDOWN_FOOTNOTES |
  LOWDOWN_AUTOLINK |
  LOWDOWN_TABLES |
  LOWDOWN_SUPER |
  LOWDOWN_STRIKE |
  LOWDOWN_FENCED |
  LOWDOWN_COMMONMARK |
  LOWDOWN_DEFLIST |
  LOWDOWN_IMG_EXT |
  LOWDOWN_METADATA;
opts.oflags = LOWDOWN_HTML_HEAD_IDS |
  LOWDOWN_HTML_NUM_ENT |
  LOWDOWN_HTML_OWASP |
  LOWDOWN_SMARTY |
  LOWDOWN_STANDALONE;
if (!lowdown_buf(&opts, buf, bufsz, &obuf, &obufsz, NULL))
  errx(1, "lowdown_buf");
fwrite(buf, 1, bufsz, stdout);
free(buf);
free(obuf);

lowdown(3), lowdown_metaq_free(3)

July 15, 2021 OpenBSD 6.7