Add global unihash table; use universal hashing instead of CRC.

[mLib] / unihash-mkstatic.c

/* -*-c-*-
 *
 * $Id: unihash-mkstatic.c,v 1.1 2003/12/15 20:52:56 mdw Exp $
 *
 * Build static universal hash tables
 *
 * (c) 2003 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------* 
 *
 * This file is part of the mLib utilities library.
 *
 * mLib is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 * 
 * mLib is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with mLib; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

/*----- Revision history --------------------------------------------------* 
 *
 * $Log: unihash-mkstatic.c,v $
 * Revision 1.1  2003/12/15 20:52:56  mdw
 * New program to make fixed tables for universal hashing.
 *
 */

/*----- Header files ------------------------------------------------------*/

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "macros.h"
#include "mdwopt.h"
#include "quis.h"
#include "report.h"
#include "unihash.h"

/*----- Main code ---------------------------------------------------------*/

#define BSCOL 72

static unsigned long getint(const char *p, unsigned long max,
			    const char *what)
{
  char *pp;
  unsigned long x = strtoul(p, &pp, 0);
  if (*pp || (max && x > max))
    die(EXIT_FAILURE, "bad %s `%s'", what, p);
  return (x);
}

static void version(FILE *fp)
{
  pquis(fp, "$, mLib version " VERSION "\n");
}

static void usage(FILE *fp)
{
  pquis(fp, "Usage: $ [-c] [-o FILE] [-g GUARD] [-i HEADER] [-s SYM]\n\
	[-k KEY]\n");
}

static void help(FILE *fp)
{
  version(fp);
  putc('\n', stdout);
  usage(fp);
  fputs("\n\
Emits a precomputed unihash_info structure for a given key.\n\
\n\
-h, --help		Show this help text.\n\
-v, --version		Show the program's version number.\n\
-u, --usage		Show a terse usage message.\n\
\n\
-c, --c-source		Emit a C source file rather than a header.\n\
-k, --key=KEY		Use KEY as the universal hashing key.\n\
-g, --guard=GUARD	Use GUARD as a multiple-inclusion guard constant.\n\
-i, --include=HEADER	Include HEADER at top of C source file.\n\
-s, --symbol=SYM	Name the generated table SYM.\n\
-o, --output=FILE	Write the output to FILE.\n\
", stdout);
}

int main(int argc, char *argv[])
{
  uint32 key = 0xe07e5bd1;
  unsigned flags = 0;
  const char *sym = 0;
  const char *inc = 0;
  const char *guard = 0;
  const char *file = 0;
  FILE *fp;
  unihash_info u;
  int i, j, k;

#define f_bogus 1u
#define f_ctab 2u

  ego(argv[0]);

  for (;;) {
    static struct option opts[] = {
      { "help",		0,		0,	'h' },
      { "version",	0,		0,	'v' },
      { "usage",	0,		0,	'u' },

      { "output",	OPTF_ARGREQ,	0,	'o' },
      { "c-source",	0,		0,	'c' },
      { "key",		OPTF_ARGREQ,	0,	'k' },
      { "symbol",	OPTF_ARGREQ,	0,	's' },
      { "include",	OPTF_ARGREQ,	0,	'i' },
      { "guard",	OPTF_ARGREQ,	0,	'g' },

      { 0,		0,		0,	0 }
    };
    int i = mdwopt(argc, argv, "hvu o:ck:s:i:g:", opts, 0, 0, 0);

    if (i < 0)
      break;
    switch (i) {
      case 'h':
	help(stdout);
	exit(0);
      case 'v':
	version(stdout);
	exit(0);
      case 'u':
	usage(stdout);
	exit(0);

      case 'o':
	file = optarg;
	break;
      case 'c':
	flags |= f_ctab;
	break;
      case 's':
	sym = optarg;
	break;
      case 'i':
	inc = optarg;
	break;
      case 'g':
	guard = optarg;
	break;
      case 'k':
	key = getint(optarg, 0xffffffff, "key");
	break;

      default:
	flags |= f_bogus;
	break;
    }
  }
  if ((flags & f_bogus) || optind != argc) {
    usage(stderr);
    exit(EXIT_FAILURE);
  }

  /* --- Sort stuff out --- */

  unihash_setkey(&u, key);
  if (!sym)
    sym = (flags & f_ctab) ? "uhi" : "UHI_INIT";
  
  /* --- Start output --- */

  if (!file)
    fp = stdout;
  else {
    if (!(flags & f_ctab) && !guard) {
      char *p;
      const char *q;
      if ((p = malloc(strlen(file) + 1)) == 0)
	die(EXIT_FAILURE, "not enough memory");
      guard = p;
      for (q = file; *q; p++, q++) {
	if (isalnum((unsigned char)*q))
	  *p = toupper((unsigned char)*q);
	else
	  *p = '_';
      }
      *p++ = 0;
    }
    if ((fp = fopen(file, "w")) == 0)
      die(EXIT_FAILURE, "couldn't write `%s': %s", file, strerror(errno));
  }

  /* --- Dump out the first chunk of the file --- */

  fprintf(fp, "\
/* -*-c-*-\n\
 *\n\
 * Unihash table (key = %08lx) [generated]\n\
 */\n\
\n",
	  (unsigned long)key);

  if (flags & f_ctab) {
    if (inc)
      fprintf(fp, "#include \"%s\"\n\n", inc);
    else
      fputs("#include <mLib/unihash.h>\n\n", fp);
    fprintf(fp, "unihash_info %s = { {\n", sym);
  } else {
    int n;
    if (guard)
      fprintf(fp, "#ifndef %s\n#define %s\n\n", guard, guard);
    n = fprintf(fp, "#define %s { {", sym);
    while (n < BSCOL) {
      fputc('\t', fp);
      n = (n + 8) & ~7;
    }
    fputc('\n', fp);
  }

  /* --- Main output --- */

  for (i = 0; i < N(u.s); i++) {
    fputs("  {", fp);
    for (j = 0; j < N(u.s[i]); j++) {
      fputs(" {", fp);
      for (k = 0; k < N(u.s[i][j]); k++) {
	fprintf(fp, " 0x%08lx", (unsigned long)u.s[i][j][k]);
	if (k < N(u.s[i][j]) - 1) {
	  fputc(',', fp);
	  if (k % 4 == 3)
	    fputs(flags & f_ctab ? "\n     " : "\t\t\t\\\n     ", fp);
	}
      }
      if (j < N(u.s[i]) - 1) {
	fputs(flags & f_ctab ? " },\n\n   " :
	        " },\t\t\t\\\n\t\t\t\t\t\t\t\t\t\\\n   ", fp);
      }
    }
    if (i < N(u.s) - 1) {
      fputs(flags & f_ctab ? " } },\n\n" :
	    " } },\t\t\\\n\t\t\t\t\t\t\t\t\t\\\n", fp);
    }
  }

  /* --- Done --- */

  fputs(flags & f_ctab ? " } }\n} };\n" :
	" } }\t\t\\\n} }\n", fp);
  if (!(flags & f_ctab) && guard)
    fputs("\n#endif\n", fp);

  return (0);
}

/*----- That's all, folks -------------------------------------------------*/