Coverage Report

Created: 2026-01-13 06:15

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/cmark/fuzz/cmark-fuzz.c
Line
Count
Source
1
/* for fmemopen */
2
#define _POSIX_C_SOURCE 200809L
3
4
#include <stdint.h>
5
#include <stdio.h>
6
#include <stdlib.h>
7
#include <string.h>
8
#include "cmark.h"
9
10
222
int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
11
222
  struct __attribute__((packed)) {
12
222
    int options;
13
222
    int width;
14
222
  } fuzz_config;
15
16
222
  if (size >= sizeof(fuzz_config)) {
17
    /* The beginning of `data` is treated as fuzzer configuration */
18
222
    memcpy(&fuzz_config, data, sizeof(fuzz_config));
19
222
    int options = fuzz_config.options;
20
21
    /* Mask off valid option bits */
22
222
    options &= (CMARK_OPT_SOURCEPOS | CMARK_OPT_HARDBREAKS | CMARK_OPT_UNSAFE | CMARK_OPT_NOBREAKS | CMARK_OPT_NORMALIZE | CMARK_OPT_VALIDATE_UTF8 | CMARK_OPT_SMART);
23
24
    /* Remainder of input is the markdown */
25
222
    const char *markdown = (const char *)(data + sizeof(fuzz_config));
26
222
    size_t markdown_size = size - sizeof(fuzz_config);
27
222
    cmark_node *doc = NULL;
28
29
    /* Use upper bits of options to select parsing mode */
30
222
    switch (((unsigned) fuzz_config.options >> 30) & 3) {
31
101
      case 0:
32
101
        doc = cmark_parse_document(markdown, markdown_size, options);
33
101
        break;
34
35
55
      case 1:
36
55
        if (markdown_size > 0) {
37
55
          FILE *file = fmemopen((void *) markdown, markdown_size, "r");
38
55
          doc = cmark_parse_file(file, options);
39
55
          fclose(file);
40
55
        }
41
55
        break;
42
43
36
      case 2: {
44
36
        size_t block_max = 20;
45
36
        cmark_parser *parser = cmark_parser_new(options);
46
47
838k
        while (markdown_size > 0) {
48
837k
          size_t block_size = markdown_size > block_max ? block_max : markdown_size;
49
837k
          cmark_parser_feed(parser, markdown, block_size);
50
837k
          markdown += block_size;
51
837k
          markdown_size -= block_size;
52
837k
        }
53
54
36
        doc = cmark_parser_finish(parser);
55
36
        cmark_parser_free(parser);
56
36
        break;
57
0
      }
58
59
30
      case 3:
60
30
        free(cmark_markdown_to_html(markdown, markdown_size, options));
61
30
        break;
62
222
    }
63
64
222
    if (doc != NULL) {
65
192
      free(cmark_render_commonmark(doc, options, fuzz_config.width));
66
192
      free(cmark_render_html(doc, options));
67
192
      free(cmark_render_latex(doc, options, fuzz_config.width));
68
192
      free(cmark_render_man(doc, options, fuzz_config.width));
69
192
      free(cmark_render_xml(doc, options));
70
71
192
      cmark_node_free(doc);
72
192
    }
73
222
  }
74
222
  return 0;
75
222
}