/*\v
  % write table of contents (only in single file mode):
      \ifmfiles\else\pagenumbering{roman}
      \tableofcontents\newpage\pagenumbering{arabic}\fi
      \centerline{\huge\bf File tiny\_t2l.l}
*/

/*\b
   <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
   <<<<<<<<<<<<<<<<<<<<<<<<<<<<***********************>>>>>>>>>>>>>>>>>>>>>>>>
   <*  filename  :  tiny_t2l.l                                              *>
   <*  purpose   :  this is a little lex file as an example for a simple    *>
   <*            :  converter using the position macros. Only a few         *>
   <*            :  basic conversions are implemented; all fonts etc. are   *>
   <*            :  hard-coded. You may use this file as example for use    *>
   <*            :  of the position macros or as starting point for an own  *>
   <*            :  converter project.                                      *>
   <*            :                                                          *>
   <*  cvt2ltx   :  This file is the tiny version of c2ltx; keywords,       *>
   <*  equiv.    :  strings and comments are recognized. A very simple      *>
   <*            :  version of embedded LaTeX is implemented (only append   *>
   <*            :  mode and verbatim mode; everything is copied verbatim   *>
   <*            :  to the output file in both cases.                       *>
   <*            :                                                          *>
   <*  version   :  1.4.0 from 25-feb-2000                                  *>
   <*  author    :  Michael Plugge <m.plugge@fh-mannheim.de>                *>
   <<<<<<<<<<<<<<<<<<<<<<<<<<<<***********************>>>>>>>>>>>>>>>>>>>>>>>>
   <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
*/

%{
   /*\v \section{Declaration Part} */
#define VERSION "1.4.0"
#define VERSION_DATE "25-feb-2000"

#define TAB2SPC 3
#define BASE_FONT "basefont"
#define BLOCK_FONT "blockfont"
#define KEYWORD_FONT "keywordfont"
#define STRING_FONT "stringfont"
#define COMMENT_FONT "commentfont"
#define HEADFONT "headfont"
#define FOOTFONT "footfont"
#define LHEAD ""
#define CHEAD "Produced from %f on %D %t"
#define RHEAD ""
#define LFOOT "" 
#define CFOOT "Page %p"
#define RFOOT ""
#define L2E_STYLE " \\documentclass[10pt]{article}\n\
 \\usepackage{a4,position,fancyhdr}\n\
 \\usepackage[latin1]{inputenc}\n\
 \\textwidth18cm\\textheight25cm\\hoffset-3cm\\voffset-1cm"
#define L209_STYLE " \\documentstyle[a4,position,fancyhdr]{article}\n\
 \\textwidth18cm\\textheight25cm\\hoffset-3cm\\voffset-1cm"
#define L2E_STYLE_LINE " \\documentclass[10pt]{article}\n\
 \\usepackage{a4,position,fancyhdr}\n\
 \\usepackage[latin1]{inputenc}\n\
 \\textwidth18cm\\textheight25cm\\hoffset-3cm\\voffset-1cm"
#define L209_STYLE_LINE " \\documentstyle[a4,position,fancyhdr]{article}\n\
 \\textwidth18cm\\textheight25cm\\hoffset-3cm\\voffset-1cm"

#define LEN(val) if((leng+=val)>70){leng=0; fprintf(yyout,"%%\n  ");}
#if VMS
#undef ECHO
#define ECHO yyleng==1 ? fputc(*yytext,yyout) : fprintf(yyout,"%s",yytext)
#endif

#include <string.h>
#include <time.h>

char *ptr,*ptr1,*kern,*inputname,buffer[256],init=1,cmt_mode;
int pos,old_pos,brace_open,tmp,leng,tab2spc=TAB2SPC,skip_cnt,cmt_pos,line=1,show_lines,use_header=1;
long year;
time_t time_val;
struct tm *atime;

char *lhead=LHEAD,*chead=CHEAD,*rhead=RHEAD,*headfont=HEADFONT,
     *lfoot=LFOOT,*cfoot=CFOOT,*rfoot=RFOOT,*footfont=FOOTFONT,
     *latex_prolog1=
"%%%% This file was generated by tiny_t2l (version %s, %s)\n\n\
\\ifx\\getformat\\undefined\n\
 \\newcount\\getformat\\getformat0\n\
\\else\n\
 \\mfilestrue\\getformat3\n\
\\fi\n\
\\ifx\\documentclass\\undefined\\advance\\getformat1\\fi\n\n\
\\ifcase\\getformat\n\
%s\n\
\\or\n\
%s\n\
\\else\\fi %% multiple file input: don't load format\n%s",

   *latex_prolog2="\\ifmfiles\\else\\begin{document}\\fi\\begin{flushleft}\n\n",

*month[]={
   "January",
   "February",
   "March",
   "April",
   "May",
   "June",
   "July",
   "August",
   "September",
   "October",
   "November",
   "December"
},
*local_month[]={
   "Januar",
   "Februar",
   "März",
   "April",
   "Mai",
   "Juni",
   "Juli",
   "August",
   "September",
   "Oktober",
   "November",
   "Dezember"
},
*month1[]={"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"},
*local_month1[]={"Jan","Feb","Mrz","Apr","Mai","Jun","Jul","Aug","Sep","Okt","Nov","Dez"},
*usage_text1="   Usage: tiny_t2l [options] [infile [outfile]] [options]\n\
   infile and/or outfile may be omitted; in this case stdin/stdout are used.\n\
   valid options are:\n\
    -hn        don't generate header or footer text\n\
    -hl<txt>   header text: left side (default \"\")\n\
    -hc<txt>   header text: center (default \"Produced from %f on %D %t\")\n\
    -hr<txt>   header text: right side (default \"\")\n\
    -fl<txt>   footer text: left side (default \"\")\n\
    -fc<txt>   footer text: center (default \"Page %p\")\n\
    -fr<txt>   footer text: right side (default \"\")\n\
      possible escape sequences for the -h. and -f. switches are:\n\
         %f: input file name        %m: month (numeric value)\n\
         %p: page number            %n: (english) name of month (full form)\n\
         %t: time (HH:MM)           %s: (english) name of month (short form)\n\
         %D: date (DD-MMM-YYYY)     %N: (local) name of month (full form)\n\
         %h: hour                   %S: (local) name of month (short form)\n\
         %M: minute                 %y: year\n\
         %d: day of month           %: the `%' character itself\n\
    -o         outputname (if stdin is used for input)\n\
    -t<cnt>    number of spaces per tab character (default: ",
*usage_text2=")\n\
    -d         debug (debug output is written to tiny_t2l.dbg)\n\
    -?         show this help screen\n";

void keyword(void);
void skip_msg(void);
void print_jmpo(int linebegin);
void init_out(int mode);
int die(char *cmd,int mode);
void substitute_format(char *format);
char *subst(int c);
void current_line(void);
%}

SP       [ \t]+
SPO      [ \t]*
WS       [ \t\n]
WSO      [ \t\n]*
WSSEMI   [ \t\n;]
WSBRSEMI [ \t\n(;]
WSBR     [ \t\n(]
WSBR2    [ \t\n)]
WSBC     [ \t\n{]
WSS      [ \t\n*]
WSSB     [ \t\n*)]
WSC      [ \t\n:]
OPER     [ \t\n+\-*/%|&^~!=<>\[(,]
CA       [ \t\n<]
WSB2     [ \t\n\[(]
NEW_DEL  [ \t\n\[(<]

%x LINE_BEGIN OMIT

%option 8bit noyywrap outfile="tiny_t2l.c" debug

%%
      /*\v \section{Rules section}\subsection{\LaTeX Prolog} */
   if(show_lines)
      fprintf(yyout,latex_prolog1,VERSION,VERSION_DATE,L2E_STYLE_LINE,
         L209_STYLE_LINE,use_header?"\\pagestyle{fancy}\n":"");   
   else
      fprintf(yyout,latex_prolog1,VERSION,VERSION_DATE,L2E_STYLE,
         L209_STYLE,use_header?"\\pagestyle{fancy}\n":"");
      fprintf(yyout,"\\plcntmargin{777}\n");
   if(use_header){
      fprintf(yyout,"\\lhead{\\%s ",headfont);
      substitute_format(lhead);
      fprintf(yyout,"\\chead{\\%s ",headfont);
      substitute_format(chead);
      fprintf(yyout,"\\rhead{\\%s ",headfont);
      substitute_format(rhead);
      fprintf(yyout,"\\lfoot{\\%s ",footfont);
      substitute_format(lfoot);
      fprintf(yyout,"\\cfoot{\\%s ",footfont);
      substitute_format(cfoot);
      fprintf(yyout,"\\rfoot{\\%s ",footfont);
      substitute_format(rfoot);
   }
   if(!show_lines)
      fprintf(yyout,"\\plinenowidth0pt\n");
   else
      fprintf(yyout,"\\plcntmargin{77}\n");
   fprintf(yyout,latex_prolog2);
   BEGIN(LINE_BEGIN);

      /*\v \subsection{Rules for Line Begin} */
<LINE_BEGIN>{
   /* special cases: blank lines, Blanks at end of line */
 ^{SPO}\n   {
      fprintf(yyout,"\\init0");
      current_line();
      fprintf(yyout,"\\n\n");
      pos=brace_open=0;
      line++;
   }
 {SP}$          /* ignore spaces at end of line */

   /* general line begin (we need the \init macro here) */
 ^" "    pos++; fprintf(yyout,"\\init1"); current_line(); fprintf(yyout,"\\njo{-1}{"); brace_open=1; leng=16; BEGIN(INITIAL);
 ^{SP}   print_jmpo(1); BEGIN(INITIAL);
 ^[^ \t\n]  {
      fprintf(yyout,"\\init0"); current_line(); fprintf(yyout,"\\njo0{");
      yyless(0);
      brace_open=1;
      leng=14;
      cmt_pos=1;
      BEGIN(INITIAL);
   }
 .    yyless(0); cmt_pos=pos+1; BEGIN(INITIAL);
}

   /*\v \subsection{Rules for Blanks and Tabs} */
{
 " " {
      pos++; 
      if(brace_open)fputc('}',yyout); 
      fprintf(yyout,"\\njo{%d}{",pos); 
      brace_open=1; 
      LEN(10);
   }
 {SP} print_jmpo(0);
}

\n {
      if(brace_open)fputc('}',yyout);
      line++;
      pos=leng=brace_open=0;
      fprintf(yyout,"\\n\n"); 
      BEGIN(LINE_BEGIN);
   }

{
 {SP}$          /* ignore spaces at end of line */

   /*\v \subsection{Rules for special characters} */
 \<{2,9}       init_out(0); fprintf(yyout,"\\mlt{%d}",yyleng); LEN(7);
 \>{2,9}       init_out(0); fprintf(yyout,"\\mgt{%d}",yyleng); LEN(7);
 \\{2,}        init_out(0); fprintf(yyout,"\\bs{%d}",yyleng); LEN(6);
 \*{2,9}       init_out(0); fprintf(yyout,"\\mast{%d}",yyleng); LEN(8);

   /*\v \subsection{``Leader'' rules} */
 \<{10,}  |
 \>{10,}  |
 \+{10,}  |
 \${10,}  |
 \#{10,}  |
 \%{10,}  |
 \~{10,}  |
 \*{10,}  {
      switch(*yytext){
         case '<':  kern="-2pt";  ptr="$<$";      break;
         case '>':  kern="-2pt";  ptr="$>$";      break;
         case '+':  kern="0pt";   ptr="+";        break;
         case '$':  kern="0pt";   ptr="\\$";      break;
         case '#':  kern="0pt";   ptr="\\#";      break;
         case '%':  kern="0pt";   ptr="\\%";      break;
         case '~':  kern="0pt";   ptr="$\\sim$";  break;
         case '*':  kern="2pt";   ptr="$\\ast$";  break;
         default:   kern="0pt";   ptr="";         break;
      }
      if(brace_open)fputc('}',yyout);
      fprintf(yyout,"\\mpout{%d}{%d}{%s}{%s}",pos,pos+yyleng-1,ptr,kern);
      pos+=yyleng;
      brace_open=0;
      LEN(strlen(kern)+strlen(ptr)+19);
   }
}


{
 . {
      init_out(0); 
      fprintf(yyout,"%s",subst(*yytext));
   }
 \f\n?         fprintf(yyout,"\\newpage\n"); if(*(yytext+yyleng-1)=='\n')line++;
 [a-zA-Z0-9]+  init_out(0); fprintf(yyout,"%s",yytext);
}

      /*\v \subsection{Rules for omitting Code} */
<LINE_BEGIN>{
 {SPO}"/*"\\o[q+]"*/"{SPO}\n  {
      for(ptr=yytext;*ptr++!='o';);
      if(*ptr=='+')
         skip_cnt=0; 
      else
         skip_cnt= -1;
      tmp= -1;
      BEGIN(OMIT);
      line++;
   }
 {SPO}"/*"\\o[1-9]+q?"*/"{SPO}\n {
      for(ptr=yytext;*ptr++!='o';);
      tmp=atoi(ptr);
      skip_cnt= -1;
      for(;*ptr && *ptr!='q';ptr++)if(*ptr=='*')skip_cnt=0;
      BEGIN(OMIT);
      line++;
   }      
}

<OMIT>{
 {SPO}"/*\\o-*/"{SPO}\n {
      skip_msg();
      brace_open=0;
      BEGIN(LINE_BEGIN);
      line++;
   }
 \*+
 \/+
 \\
 [^\\\"*\/\n]+     /* skip */
 \n {
      if(skip_cnt>=0)skip_cnt++;
      line++;
      if(!--tmp){
         skip_msg();
         brace_open=0;
         BEGIN(LINE_BEGIN);
      }
   }
 <<EOF>> skip_msg(); yyterminate();
}

%%

   /*\v \subsection{Function skip\_msg(void)} */
void skip_msg(void)
{
   if(skip_cnt==1)
      fprintf(yyout,"\\par\\centerline{/\\mast{20}{ \\commentfont SKIP A LINE }\\mast{20}/}\\par\n");
   else if(skip_cnt>1)
      fprintf(yyout,"\\par\\centerline{/\\mast{20}{ \\commentfont SKIP %d LINES }\\mast{20}/}\\par\n",skip_cnt);
}

   /*\v \subsection{Function init\_out(void)} */
void init_out(int mode)
{
      /* mode==0: kein \cmtinit
       * mode==1: \cmtinit für C-Kommentar
       * mode==2: \cmtinit für C++-Kommentar
       */
   pos+=yyleng;
   if(mode==0){
      if(!brace_open){
         fprintf(yyout,"\\njo0{");
         leng+=7;
      }
   }
   brace_open=1;
}

   /*\v \subsection{Function print\_jmpo(int linebegin)} */
void print_jmpo(int linebegin)
{
   int old=pos;
   for(ptr=yytext;*ptr==' ' || *ptr=='\t';ptr++){
      if(*ptr=='\t')
         pos+=tab2spc-pos%tab2spc;
      else
         pos++;
   }
   if(linebegin){
      fprintf(yyout,"\\init{%d}",pos);
      current_line();
      fprintf(yyout,"\\njo{%d}{",-pos);
      leng=18;
   }
   else if(brace_open){
      fputc('}',yyout);
         fprintf(yyout,"\\jmpo{%d}{",pos);
         LEN(10);
   }
   else{
         fprintf(yyout,"\\jmpo{%d}{",pos);
         LEN(10);
   }
   brace_open=1;
}

   /*\v \subsection{Function die(char *cmd,int mode)} */
int die(char *cmd,int mode)
{
   switch(mode){
      case 1:
         fprintf(stderr,"Can't open %s for read; exit\n",cmd);
         exit(4);
      case 2:
         fprintf(stderr,"Can't open %s for write; exit\n",cmd);
         exit(4);
      case 3:
         fprintf(stderr,"%s\n",cmd);
         exit(4);
      default:
         return 0;
   }
}

   /*\v \subsection{Function subst(int c)} */
char *subst(int c)
{
   static char retbuffer[2];

   if(c<0)c+=256;
   switch(c){
      case '#':   leng+=2; return "\\#";
      case '$':   leng+=2; return "\\$";
      case '%':   leng+=2; return "\\%";
      case '&':   leng+=2; return "\\&";
      case '\'':  leng+=3; return "\\sq{}";
      case '*':   leng+=6; return "$\\ast$";
      case '-':   leng+=5; return "{\\mm}";
      case '<':   leng+=3; return "$<$";
      case '>':   leng+=3; return "$>$";
      case '[':   leng+=3; return "{[}";
      case '\\':  leng+=4; return "\\bs{1}";
      case ']':   leng+=3; return "{]}";
      case '^':   leng+=9; return "$\\hat{~}$";
      case '_':   leng+=5; return "{\\ul}";
      case '`':   leng+=3; return "{`}";
      case '{':   leng+=6; return "\\brl{}";
      case '|':   leng+=6; return "$\\mid$";
      case '}':   leng+=6; return "\\brr{}";
      case '~':   leng+=6; return "$\\sim$";
      case '"':   leng+=7; return "{\\tt \"}";
      default:    leng++; *retbuffer=c; return retbuffer;
   }
}

   /*\v \subsection{Function substitute\_format(char *format)} */
void substitute_format(char *format)
{
   char c,*ptr1;

   for(ptr=format;*ptr;ptr++){
      if(*ptr=='%'){          /* escape sequences: */
         switch(*++ptr){
            case 'd':         /* %d: day of month */
               fprintf(yyout,"%d",atime->tm_mday);
               break;
            case 'D':         /* %D: date (format DD-MMM-YYYY) */
               fprintf(yyout,"%d{\\mm}%s{\\mm}%ld",atime->tm_mday,month1[atime->tm_mon],year);
               break;
            case 'f':         /* %f: input file name */
               for(ptr1=inputname;*ptr1;)fprintf(yyout,"%s",subst(*ptr1++));
               break;
            case 'h':
               fprintf(yyout,"%02d",atime->tm_hour);
               break;
            case 'm':         /* %m: month (numeric value) */
               fprintf(yyout,"%d",atime->tm_mon+1);
               break;
            case 'M':         /* %M: minute */
               fprintf(yyout,"%02d",atime->tm_min);
               break;
            case 'n':         /* %n: (english) name of month (full form) */
               fprintf(yyout,"%s",month[atime->tm_mon]);
               break;
            case 'N':         /* %N: (local) name of month (full form) */
               fprintf(yyout,"%s",local_month[atime->tm_mon]);
               break;
            case 's':         /* %s: (english) name of month (short form) */
               fprintf(yyout,"%s",month1[atime->tm_mon]);
               break;
            case 'S':         /* %S: (local) name of month (short form) */
               fprintf(yyout,"%s",local_month1[atime->tm_mon]);
               break;
            case 'p':         /* %p: page (in the LaTeX file) */
               fprintf(yyout,"\\thepage");
               break;
            case 't':         /* %t: time (format HH:MM) */
               fprintf(yyout,"%02d:%02d",atime->tm_hour,atime->tm_min);
               break;
            case 'y':         /* %y: year */
               fprintf(yyout,"%ld",year);
               break;
            case '%':         /* %%: the `%' character itself */
               fputc('\\',yyout);
               fputc('%',yyout);
               break;
            default:          /* unknown escape sequence: just print it out */
               fprintf(stderr,"Unknown escape sequence `%%%c' detected; print it out.\n",*ptr);
               fprintf(stderr,"(format string was >%s<)\n",format);
               fputc('%',yyout);
               fprintf(yyout,"%s",subst(*ptr));
               break;
         }
      }
      else
         fprintf(yyout,"%s",subst(*ptr));
   }
   fprintf(yyout,"}\n");
}

   /*\v \subsection{Function current\_line(void)} */
void current_line(void)
{
   if(show_lines>0 && line%show_lines==0){
      fprintf(yyout,"{%d}",line);
   }
   else
      fprintf(yyout,"{}");
   LEN(10);
}

   /*\v \subsection{Function main(int argc, char **argv)} */
int main(int argc, char **argv)
{
   int i;

#ifdef FLEX_DEBUG
   yy_flex_debug=0;
#endif   /* FLEX_DEBUG */
   time(&time_val);
   atime=localtime(&time_val);
   year=time_val/(365L*24L*60L*60L)+1970L;
   for(i=1;i<argc;i++){
   	if(*argv[i]=='-'){
   	   for(ptr=argv[i]+1;*ptr;)switch(*ptr++){
   	      case 'd':
#ifdef FLEX_DEBUG
               yy_flex_debug=1;
#else
               fprintf(stderr,"tiny_t2l was compiled without debug info; ignore switch -d\n");
#endif 
               break;
            case 'h':
               switch(*ptr++){
                  case 'n': use_header=0; break;   /* no header */
                  case 'l': lhead=ptr; break;      /* left header text */
                  case 'c': chead=ptr; break;      /* center header text */
                  case 'r': rhead=ptr; break;      /* right header text */
                  default: break;
               }
               while(*ptr)ptr++;   /* forget the rest of the argument */
            break;
            case 'l':
               if(*ptr)
                  show_lines=atoi(ptr);
               else
                  show_lines=5;
               while(*ptr)ptr++;   /* forget the rest of the argument */
               break;
            case 'f':
               switch(*ptr++){
                  case 'l': lfoot=ptr; break;      /* left footer text */
                  case 'c': cfoot=ptr; break;      /* center footer text */
                  case 'r': rfoot=ptr; break;      /* right footer text */
                  default: break;
               }
               while(*ptr)ptr++;   /* forget the rest of the argument */
            break;
            case 'o': /* output name */
               if(!yyout)(yyout=fopen(ptr,"w")) || die(ptr,2);
               break;
            case 't':
               tab2spc=atoi(ptr);
               break;
            case '?':
               fprintf(stderr,"tiny_t2l Version %s (%s)\n%s%d%s",
                  VERSION,VERSION_DATE,usage_text1,TAB2SPC,usage_text2);
#if VMS
               exit(1);
#else
               exit(0);
#endif
            default:
               break;
         }
      }
      else if(!yyin)   /* argument without leading '-': input or output name */
         (yyin=fopen(inputname=argv[i],"r")) || die(inputname,1);
      else if(!yyout)
         (yyout=fopen(argv[i],"w")) || die(argv[i],2);
   }
   if(!yyin)yyin=stdin;       /* no inputname specified */
   if(!yyout)yyout=stdout;    /* no outputname specified */
   if(inputname){
      for(ptr=inputname,ptr1=buffer;*ptr;)
         switch(*ptr){
            case '_':
            case '$': *ptr1++='\\';
            default:
               *ptr1++= *ptr++;
               break;
         }
      *ptr1=0;
   }
   else
      strcpy(buffer,inputname="(stdin)");
#ifdef FLEX_DEBUG
   if(yy_flex_debug){
         /* FLEX gives very much debug info; write the stuff to a file */
      fprintf(stderr,"redirect stderr to file tiny_t2l.dbg\n");
      (freopen("tiny_t2l.dbg","w",stderr))
         || die("error opening file tiny_t2l.dbg for stderr (freopen)",3);
   }
#endif   /* FLEX_DEBUG */
   yylex();

      /* write the end of the LaTeX file */
   if(brace_open)fputc('}',yyout);
   fprintf(yyout,"\\end{flushleft}\n\
\\ifmfiles\\def\\END{\\relax}\\else\\def\\END{\\end{document}}\\fi\n\
\\END\n");
   fclose(yyin);
   fclose(yyout);
}