From garlick@ecst.csuchico.edu Tue Apr 5 09:46:10 1994 Article: 12169 of comp.infosystems.www From: garlick@ecst.csuchico.edu (Jim Garlick) Subject: convert nroff output to html Date: Mon, 4 Apr 94 19:14:46 GMT-1:00 Organization: California State University, Chico Here's a C program I wrote which converts the output of nroff to html by mapping backspace/overstrikes to , backspace/underbar to , and several overstruck chars to chars that are sane in html. It escapes the html special chars '<', '>', and '&'. It's a filter. To convert a troff document to html, run through nroff and pipe the output through man2html. Awfully simple-minded, but the results aren't half bad! Jim Garlick CSU Chico /* * man2html.c -- convert nroff output to html * * Convert backspace/overstrikes to bold. * Convert backspace/underbar (either order) to italic. * Convert bar/backspace/dash to `+' (also handle bold rendering) * Convert bar/backspace/equals to `*' (also handle bold rendering) * Convert plus/backspace/o to `o' * Convert `<' to `<'; `>' to `>'; and `&' to `&' * If -u specified, compress duplicate blank lines. * * $Id: man2html.c,v 1.11 1994/04/01 19:03:18 garlick Exp $ */ #include #define BUFSIZE 4096 main(argc, argv) int argc; char *argv[]; { char buf[BUFSIZE]; static int blank = 1, uopt = 0, lineno = 0, bksp = 0; /* * Options. */ if (argc > 2) usage(); if (argc == 2) { if (strcmp(argv[1], "-u") == 0) uopt = 1; else usage(); } /* * Enclose in html envelope */ puts("
"); /* * Process each line. Count unresolved backspaces and issue * a warning message at the end. */ while (fgets(buf, BUFSIZE, stdin)) { lineno++; /* * if -u specified, compress duplicate blank lines */ if (uopt) { if (blankline(buf)) { if (blank) continue; else blank = 1; } else blank = 0; } bksp += html(buf, lineno); } /* * Close html envelope. */ puts("
"); /* * Warn about any unresolved backspaces. */ if (bksp > 0) fprintf(stderr, "man2html: warning: %d unresolved backspaces\n", bksp); exit(0); } usage() { fprintf(stderr, "man2html: usage: man2html [-u]\n"); exit(1); } /* * Given a line, print it out as html. * Return the number of unprocessed backspaces in this line. */ int html(s, lineno) char *s; int lineno; { char *p; int bold, italic, bksp; unsigned char buf2[BUFSIZE]; /* * two bits in each element of buf2 indicate attributes of * corresponding character in `s'. * bit 1, when set, indicates bold * bit 2, when set, indicates underscore */ /* * pass 1: set character attributes (and delete overstrikes) */ bzero(buf2, BUFSIZE); for (p = s; *p; p++) { if (p == s || *p != '\b') continue; /* detect a backspace/overstrike (bold ) */ if (*(p - 1) == *(p + 1)) { /* get rid of backspace and overstrike */ strcpy(p - 1, p + 1); /* flag character as bold */ buf2[p - 1 - s] |= 1; p--; /* detect an underbar/backspace (italic ) */ } else if (*(p - 1) == '_') { /* get rid of backspace and underbar */ strcpy(p - 1, p + 1); /* flag character as underscored */ buf2[p - 1 - s] |= 2; p--; /* detect a backspace/underbar (reverse of above) */ } else if (*(p + 1) == '_') { /* get rid of backspace and underbar */ strcpy(p, p + 2); /* flag character as underscored */ buf2[p - 1 - s] |= 2; p--; /* convert bar/backspace/dash to `+' */ } else if (strncmp(p - 1, "|\b-", 3) == 0 || strncmp(p - 1, "+\b-", 3) == 0 || strncmp(p - 1, "+\b|", 3) == 0) { /* get rid of backspace and bar, change dash to `+' */ strcpy(p - 1, p + 1); *(p - 1) = '+'; p--; /* convert bar/backspace/equals to `*' */ } else if (strncmp(p - 1, "|\b=", 3) == 0 || strncmp(p - 1, "*\b=", 3) == 0 || strncmp(p - 1, "*\b|", 3) == 0) { strcpy(p - 1, p + 1); *(p - 1) = '*'; p--; /* convert plus/backspace/o to bold `o' */ } else if (strncmp(p - 1, "+\bo", 3) == 0 || strncmp(p - 1, "o\b+", 3) == 0) { strcpy(p - 1, p + 1); *(p - 1) = 'o'; /* flag character as bold */ buf2[p - 1 - s] |= 1; p--; } } /* * pass 2: print out line as html */ bold = italic = bksp = 0; for (p = s; *p; p++) { /* bold */ if (buf2[p - s] & 1) { if (!bold) { /* * an overstrike/underbar is ambiguous. * change to italic if we are in an italic * context right now */ if (italic && *p == '_') buf2[p - s] |= 2; else { fputs("", stdout); bold = 1; } } } else { if (bold && *p != ' ') { fputs("", stdout); bold = 0; } } /* italic */ if (buf2[p - s] & 2) { if (!italic) { fputs("", stdout); italic = 1; } } else { if (italic && *p != ' ') { fputs("", stdout); italic = 0; } } /* print the char, escaping the three html special chars */ switch (*p) { case '<': fputs("<", stdout); break; case '>': fputs(">", stdout); break; case '&': fputs("&", stdout); break; case '\b': #ifdef notdef fprintf(stderr, "man2html: warning, \\b on line %d\n", lineno); #endif bksp++; default: putchar(*p); } } if (bold) fputs("", stdout); if (italic) fputs("", stdout); return(bksp); } int blankline(s) char *s; { while (*s) { if (!isspace(*s)) return(0); s++; } return(1); }