text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   * conmakehash.c
   *
   * Create arrays for initializing the kernel folded tables (using a hash
   * table turned out to be to limiting...)  Unfortunately we can't simply
   * preinitialize the tables at compile time since kfree() cannot accept
   * memory not allocated by kmalloc(), and doing our own memory management
   * just for this seems like massive overkill.
   *
   * Copyright (C) 1995-1997 H. Peter Anvin
   */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <sysexits.h>
  #include <string.h>
  #include <ctype.h>
  
  #define MAX_FONTLEN 256
  
  typedef unsigned short unicode;
  
  static void usage(char *argv0)
  {
    fprintf(stderr, "Usage: \n"
           "        %s chartable [hashsize] [hashstep] [maxhashlevel]\n", argv0);
    exit(EX_USAGE);
  }
  
  static int getunicode(char **p0)
  {
    char *p = *p0;
  
    while (*p == ' ' || *p == '\t')
      p++;
    if (*p != 'U' || p[1] != '+' ||
        !isxdigit(p[2]) || !isxdigit(p[3]) || !isxdigit(p[4]) ||
        !isxdigit(p[5]) || isxdigit(p[6]))
      return -1;
    *p0 = p+6;
    return strtol(p+2,0,16);
  }
  
  unicode unitable[MAX_FONTLEN][255];
  				/* Massive overkill, but who cares? */
  int unicount[MAX_FONTLEN];
  
  static void addpair(int fp, int un)
  {
    int i;
  
    if ( un <= 0xfffe )
      {
        /* Check it isn't a duplicate */
  
        for ( i = 0 ; i < unicount[fp] ; i++ )
  	if ( unitable[fp][i] == un )
  	  return;
  
        /* Add to list */
  
        if ( unicount[fp] > 254 )
  	{
  	  fprintf(stderr, "ERROR: Only 255 unicodes/glyph permitted!\n");
  	  exit(EX_DATAERR);
  	}
  
        unitable[fp][unicount[fp]] = un;
        unicount[fp]++;
      }
  
    /* otherwise: ignore */
  }
  
  int main(int argc, char *argv[])
  {
    FILE *ctbl;
    char *tblname;
    char buffer[65536];
    int fontlen;
    int i, nuni, nent;
    int fp0, fp1, un0, un1;
    char *p, *p1;
  
    if ( argc < 2 || argc > 5 )
      usage(argv[0]);
  
    if ( !strcmp(argv[1],"-") )
      {
        ctbl = stdin;
        tblname = "stdin";
      }
    else
      {
        ctbl = fopen(tblname = argv[1], "r");
        if ( !ctbl )
  	{
  	  perror(tblname);
  	  exit(EX_NOINPUT);
  	}
      }
  
    /* For now we assume the default font is always 256 characters. */
    fontlen = 256;
  
    /* Initialize table */
  
    for ( i = 0 ; i < fontlen ; i++ )
      unicount[i] = 0;
  
    /* Now we come to the tricky part.  Parse the input table. */
  
    while ( fgets(buffer, sizeof(buffer), ctbl) != NULL )
      {
        if ( (p = strchr(buffer, '\n')) != NULL )
  	*p = '\0';
        else
  	fprintf(stderr, "%s: Warning: line too long\n", tblname);
  
        p = buffer;
  
  /*
   * Syntax accepted:
   *	<fontpos>	<unicode> <unicode> ...
   *	<range>		idem
   *	<range>		<unicode range>
   *
   * where <range> ::= <fontpos>-<fontpos>
   * and <unicode> ::= U+<h><h><h><h>
   * and <h> ::= <hexadecimal digit>
   */
  
        while (*p == ' ' || *p == '\t')
  	p++;
        if (!*p || *p == '#')
  	continue;	/* skip comment or blank line */
  
        fp0 = strtol(p, &p1, 0);
        if (p1 == p)
  	{
  	  fprintf(stderr, "Bad input line: %s\n", buffer);
  	  exit(EX_DATAERR);
          }
        p = p1;
  
        while (*p == ' ' || *p == '\t')
  	p++;
        if (*p == '-')
  	{
  	  p++;
  	  fp1 = strtol(p, &p1, 0);
  	  if (p1 == p)
  	    {
  	      fprintf(stderr, "Bad input line: %s\n", buffer);
  	      exit(EX_DATAERR);
  	    }
  	  p = p1;
          }
        else
  	fp1 = 0;
  
        if ( fp0 < 0 || fp0 >= fontlen )
  	{
  	    fprintf(stderr,
  		    "%s: Glyph number (0x%x) larger than font length\n",
  		    tblname, fp0);
  	    exit(EX_DATAERR);
  	}
        if ( fp1 && (fp1 < fp0 || fp1 >= fontlen) )
  	{
  	    fprintf(stderr,
  		    "%s: Bad end of range (0x%x)\n",
  		    tblname, fp1);
  	    exit(EX_DATAERR);
  	}
  
        if (fp1)
  	{
  	  /* we have a range; expect the word "idem" or a Unicode range of the
  	     same length */
  	  while (*p == ' ' || *p == '\t')
  	    p++;
  	  if (!strncmp(p, "idem", 4))
  	    {
  	      for (i=fp0; i<=fp1; i++)
  		addpair(i,i);
  	      p += 4;
  	    }
  	  else
  	    {
  	      un0 = getunicode(&p);
  	      while (*p == ' ' || *p == '\t')
  		p++;
  	      if (*p != '-')
  		{
  		  fprintf(stderr,
  "%s: Corresponding to a range of font positions, there should be a Unicode range\n",
  			  tblname);
  		  exit(EX_DATAERR);
  	        }
  	      p++;
  	      un1 = getunicode(&p);
  	      if (un0 < 0 || un1 < 0)
  		{
  		  fprintf(stderr,
  "%s: Bad Unicode range corresponding to font position range 0x%x-0x%x\n",
  			  tblname, fp0, fp1);
  		  exit(EX_DATAERR);
  	        }
  	      if (un1 - un0 != fp1 - fp0)
  		{
  		  fprintf(stderr,
  "%s: Unicode range U+%x-U+%x not of the same length as font position range 0x%x-0x%x\n",
  			  tblname, un0, un1, fp0, fp1);
  		  exit(EX_DATAERR);
  	        }
  	      for(i=fp0; i<=fp1; i++)
  		addpair(i,un0-fp0+i);
  	    }
          }
        else
  	{
  	    /* no range; expect a list of unicode values for a single font position */
  
  	    while ( (un0 = getunicode(&p)) >= 0 )
  	      addpair(fp0, un0);
  	}
        while (*p == ' ' || *p == '\t')
  	p++;
        if (*p && *p != '#')
  	fprintf(stderr, "%s: trailing junk (%s) ignored\n", tblname, p);
      }
  
    /* Okay, we hit EOF, now output hash table */
  
    fclose(ctbl);
  
  
    /* Compute total size of Unicode list */
    nuni = 0;
    for ( i = 0 ; i < fontlen ; i++ )
      nuni += unicount[i];
  
    printf("\
  /*\n\
   * Do not edit this file; it was automatically generated by\n\
   *\n\
   * conmakehash %s > [this file]\n\
   *\n\
   */\n\
  \n\
  #include <linux/types.h>\n\
  \n\
  u8 dfont_unicount[%d] = \n\
  {\n\t", argv[1], fontlen);
  
    for ( i = 0 ; i < fontlen ; i++ )
      {
        printf("%3d", unicount[i]);
        if ( i == fontlen-1 )
          printf("\n};\n");
        else if ( i % 8 == 7 )
          printf(",\n\t");
        else
          printf(", ");
      }
  
    printf("\nu16 dfont_unitable[%d] = \n{\n\t", nuni);
  
    fp0 = 0;
    nent = 0;
    for ( i = 0 ; i < nuni ; i++ )
      {
        while ( nent >= unicount[fp0] )
  	{
  	  fp0++;
  	  nent = 0;
  	}
        printf("0x%04x", unitable[fp0][nent++]);
        if ( i == nuni-1 )
           printf("\n};\n");
         else if ( i % 8 == 7 )
           printf(",\n\t");
         else
           printf(", ");
      }
  
    exit(EX_OK);
  }
  