js/src/jsoplengen.cpp

   1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
   2  * vim: set sw=4 ts=8 et tw=80:
   3  *
   4  * ***** BEGIN LICENSE BLOCK *****
   5  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   6  *
   7  * The contents of this file are subject to the Mozilla Public License Version
   8  * 1.1 (the "License"); you may not use this file except in compliance with
   9  * the License. You may obtain a copy of the License at
  10  * http://www.mozilla.org/MPL/
  11  *
  12  * Software distributed under the License is distributed on an "AS IS" basis,
  13  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  14  * for the specific language governing rights and limitations under the
  15  * License.
  16  *
  17  * The Original Code is String Switch Generator for JavaScript Keywords,
  18  * released 2005-12-09.
  19  *
  20  * The Initial Developer of the Original Code is
  21  * Igor Bukanov.
  22  * Portions created by the Initial Developer are Copyright (C) 2005-2006
  23  * the Initial Developer. All Rights Reserved.
  24  *
  25  * Contributor(s):
  26  *
  27  * Alternatively, the contents of this file may be used under the terms of
  28  * either of the GNU General Public License Version 2 or later (the "GPL"),
  29  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  30  * in which case the provisions of the GPL or the LGPL are applicable instead
  31  * of those above. If you wish to allow use of your version of this file only
  32  * under the terms of either the GPL or the LGPL, and not to allow others to
  33  * use your version of this file under the terms of the MPL, indicate your
  34  * decision by deleting the provisions above and replace them with the notice
  35  * and other provisions required by the GPL or the LGPL. If you do not delete
  36  * the provisions above, a recipient may use your version of this file under
  37  * the terms of any one of the MPL, the GPL or the LGPL.
  38  *
  39  * ***** END LICENSE BLOCK ***** */
  40
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44
  45 static const struct {
  46     const char  *name;
  47     int         length;
  48 } pairs[] = {
  49 #define OPDEF(op,val,name,token,length,nuses,ndefs,prec,format)               \
  50     { #op, length } ,
  51 #include "jsopcode.tbl"
  52 #undef OPDEF
  53 };
  54
  55 int
  56 main(int argc, char **argv)
  57 {
  58     FILE *fp;
  59     size_t maxNameWidth, i, nameWidth, tabStop;
  60     int lengthGap;
  61
  62     static const char prefix[] = "#define ";
  63     static const char suffix[] = "_LENGTH";
  64     static const size_t tabWidth = 8;
  65     static const size_t prefixWidth = sizeof(prefix) - 1;
  66     static const size_t suffixWidth = sizeof(suffix) - 1;
  67
  68     if (argc != 2) {
  69         fputs("Bad usage\n", stderr);
  70         return EXIT_FAILURE;
  71     }
  72
  73     fp = fopen(argv[1], "w");
  74     if (!fp) {
  75         perror("fopen");
  76         return EXIT_FAILURE;
  77     }
  78     fputs("/*\n"
  79           " * Automatically generated header with JS opcode length constants.\n"
  80           " *\n"
  81           " * Do not edit it, alter jsopcode.tbl instead.\n"
  82           " */\n",
  83           fp);
  84
  85     /*
  86      * Print
  87      *
  88      * #define name_LENGTH length
  89      *
  90      * with all length values aligned on the same column. The column is at the
  91      * second character position after a tab-stop with the first position
  92      * reserved for the minus sign of variable-length opcodes.
  93      */
  94     maxNameWidth = 0;
  95     for (i = 0; i != sizeof pairs / sizeof pairs[0]; ++i) {
  96         nameWidth = strlen(pairs[i].name);
  97         if (maxNameWidth < nameWidth)
  98             maxNameWidth = nameWidth;
  99     }
 100
 101     tabStop = prefixWidth + maxNameWidth + suffixWidth + 1;
 102     tabStop = (tabStop + tabWidth - 1) / tabWidth * tabWidth;
 103     for (i = 0; i != sizeof pairs / sizeof pairs[0]; ++i) {
 104         lengthGap = (int) (tabStop - prefixWidth - strlen(pairs[i].name) -
 105                            suffixWidth);
 106         fprintf(fp, "%s%s%s%*c%2d\n",
 107                 prefix, pairs[i].name, suffix, lengthGap, ' ',
 108                 pairs[i].length);
 109         if (ferror(fp)) {
 110             perror("fclose");
 111             exit(EXIT_FAILURE);
 112         }
 113     }
 114
 115     if (fclose(fp)) {
 116         perror("fclose");
 117         return EXIT_FAILURE;
 118     }
 119
 120     return EXIT_SUCCESS;
 121 }