cmark

 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <errno.h>
 #include "config.h"
 #include "cmark.h"
 #include "node.h"
 
 #if defined(__OpenBSD__)
 #  include <sys/param.h>
 #  if OpenBSD >= 201605
 #    define USE_PLEDGE
 #    include <unistd.h>
 #  endif
 #endif
 
 #if defined(_WIN32) && !defined(__CYGWIN__)
 #include <io.h>
 #include <fcntl.h>
 #endif
 
 typedef enum {
   FORMAT_NONE,
   FORMAT_HTML,
   FORMAT_XML,
   FORMAT_MAN,
   FORMAT_COMMONMARK,
   FORMAT_LATEX
 } writer_format;
 
 void print_usage() {
   printf("Usage:   cmark [FILE*]\n");
   printf("Options:\n");
   printf("  --to, -t FORMAT  Specify output format (html, xml, man, "
          "commonmark, latex)\n");
   printf("  --width WIDTH    Specify wrap width (default 0 = nowrap)\n");
   printf("  --sourcepos      Include source position attribute\n");
   printf("  --hardbreaks     Treat newlines as hard line breaks\n");
   printf("  --nobreaks       Render soft line breaks as spaces\n");
   printf("  --safe           Omit raw HTML and dangerous URLs\n");
   printf("  --unsafe         Render raw HTML and dangerous URLs\n");
   printf("  --smart          Use smart punctuation\n");
   printf("  --validate-utf8  Replace invalid UTF-8 sequences with U+FFFD\n");
   printf("  --help, -h       Print usage information\n");
   printf("  --version        Print version\n");
 }
 
 static void print_document(cmark_node *document, writer_format writer,
                            int options, int width) {
   char *result;
 
   switch (writer) {
   case FORMAT_HTML:
     result = cmark_render_html(document, options);
     break;
   case FORMAT_XML:
     result = cmark_render_xml(document, options);
     break;
   case FORMAT_MAN:
     result = cmark_render_man(document, options, width);
     break;
   case FORMAT_COMMONMARK:
     result = cmark_render_commonmark(document, options, width);
     break;
   case FORMAT_LATEX:
     result = cmark_render_latex(document, options, width);
     break;
   default:
     fprintf(stderr, "Unknown format %d\n", writer);
     exit(1);
   }
   printf("%s", result);
   document->mem->free(result);
 }
 
 int main(int argc, char *argv[]) {
   int i, numfps = 0;
   int *files;
   char buffer[4096];
   cmark_parser *parser;
   size_t bytes;
   cmark_node *document;
   int width = 0;
   char *unparsed;
   writer_format writer = FORMAT_HTML;
   int options = CMARK_OPT_DEFAULT;
 
 #ifdef USE_PLEDGE
   if (pledge("stdio rpath", NULL) != 0) {
     perror("pledge");
     return 1;
   }
 #endif
 
 #if defined(_WIN32) && !defined(__CYGWIN__)
   _setmode(_fileno(stdin), _O_BINARY);
   _setmode(_fileno(stdout), _O_BINARY);
 #endif
 
   files = (int *)calloc(argc, sizeof(*files));
 
   for (i = 1; i < argc; i++) {
     if (strcmp(argv[i], "--version") == 0) {
       printf("cmark %s", CMARK_VERSION_STRING);
       printf(" - CommonMark converter\n(C) 2014-2016 John MacFarlane\n");
       exit(0);
     } else if (strcmp(argv[i], "--sourcepos") == 0) {
       options |= CMARK_OPT_SOURCEPOS;
     } else if (strcmp(argv[i], "--hardbreaks") == 0) {
       options |= CMARK_OPT_HARDBREAKS;
     } else if (strcmp(argv[i], "--nobreaks") == 0) {
       options |= CMARK_OPT_NOBREAKS;
     } else if (strcmp(argv[i], "--smart") == 0) {
       options |= CMARK_OPT_SMART;
     } else if (strcmp(argv[i], "--safe") == 0) {
       options |= CMARK_OPT_SAFE;
     } else if (strcmp(argv[i], "--unsafe") == 0) {
       options |= CMARK_OPT_UNSAFE;
     } else if (strcmp(argv[i], "--validate-utf8") == 0) {
       options |= CMARK_OPT_VALIDATE_UTF8;
     } else if ((strcmp(argv[i], "--help") == 0) ||
                (strcmp(argv[i], "-h") == 0)) {
       print_usage();
       exit(0);
     } else if (strcmp(argv[i], "--width") == 0) {
       i += 1;
       if (i < argc) {
         width = (int)strtol(argv[i], &unparsed, 10);
         if (unparsed && strlen(unparsed) > 0) {
           fprintf(stderr, "failed parsing width '%s' at '%s'\n", argv[i],
                   unparsed);
           exit(1);
         }
       } else {
         fprintf(stderr, "--width requires an argument\n");
         exit(1);
       }
     } else if ((strcmp(argv[i], "-t") == 0) || (strcmp(argv[i], "--to") == 0)) {
       i += 1;
       if (i < argc) {
         if (strcmp(argv[i], "man") == 0) {
           writer = FORMAT_MAN;
         } else if (strcmp(argv[i], "html") == 0) {
           writer = FORMAT_HTML;
         } else if (strcmp(argv[i], "xml") == 0) {
           writer = FORMAT_XML;
         } else if (strcmp(argv[i], "commonmark") == 0) {
           writer = FORMAT_COMMONMARK;
         } else if (strcmp(argv[i], "latex") == 0) {
           writer = FORMAT_LATEX;
         } else {
           fprintf(stderr, "Unknown format %s\n", argv[i]);
           exit(1);
         }
       } else {
         fprintf(stderr, "No argument provided for %s\n", argv[i - 1]);
         exit(1);
       }
     } else if (*argv[i] == '-') {
       print_usage();
       exit(1);
     } else { // treat as file argument
       files[numfps++] = i;
     }
   }
 
   parser = cmark_parser_new(options);
   for (i = 0; i < numfps; i++) {
     FILE *fp = fopen(argv[files[i]], "rb");
     if (fp == NULL) {
       fprintf(stderr, "Error opening file %s: %s\n", argv[files[i]],
               strerror(errno));
       exit(1);
     }
 
     while ((bytes = fread(buffer, 1, sizeof(buffer), fp)) > 0) {
       cmark_parser_feed(parser, buffer, bytes);
       if (bytes < sizeof(buffer)) {
         break;
       }
     }
 
     fclose(fp);
   }
 
   if (numfps == 0) {
 
     while ((bytes = fread(buffer, 1, sizeof(buffer), stdin)) > 0) {
       cmark_parser_feed(parser, buffer, bytes);
       if (bytes < sizeof(buffer)) {
         break;
       }
     }
   }
 
 #ifdef USE_PLEDGE
   if (pledge("stdio", NULL) != 0) {
     perror("pledge");
     return 1;
   }
 #endif
 
   document = cmark_parser_finish(parser);
   cmark_parser_free(parser);
 
   print_document(document, writer, options, width);
 
   cmark_node_free(document);
 
   free(files);
 
   return 0;
 }