/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * This program creates syntax.h and syntax.c.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "parser.h"


struct synclass {
        const char *name;
        const char *comment;
};

/* Syntax classes */
static const struct synclass synclass[] = {
        { "CWORD",      "character is nothing special" },
        { "CNL",        "newline character" },
        { "CQNL",       "newline character in quotes" },
        { "CBACK",      "a backslash character" },
        { "CSBACK",     "a backslash character in single quotes" },
        { "CSQUOTE",    "single quote" },
        { "CDQUOTE",    "double quote" },
        { "CENDQUOTE",  "a terminating quote" },
        { "CBQUOTE",    "backwards single quote" },
        { "CVAR",       "a dollar sign" },
        { "CENDVAR",    "a '}' character" },
        { "CLP",        "a left paren in arithmetic" },
        { "CRP",        "a right paren in arithmetic" },
        { "CEOF",       "end of file" },
        { "CCTL",       "like CWORD, except it must be escaped" },
        { "CSPCL",      "these terminate a word" },
        { "CIGN",       "character should be ignored" },
        { NULL,         NULL }
};


/*
 * Syntax classes for is_ functions.  Warning:  if you add new classes
 * you may have to change the definition of the is_in_name macro.
 */
static const struct synclass is_entry[] = {
        { "ISDIGIT",    "a digit" },
        { "ISUPPER",    "an upper case letter" },
        { "ISLOWER",    "a lower case letter" },
        { "ISUNDER",    "an underscore" },
        { "ISSPECL",    "the name of a special parameter" },
        { NULL,         NULL }
};

static const char writer[] = "\
/*\n\
 * This file was generated by the mksyntax program.\n\
 */\n\
\n";


static FILE *cfile;
static FILE *hfile;

static void add_default(void);
static void finish(void);
static void init(const char *);
static void add(const char *, const char *);
static void output_type_macros(void);

int
main(int argc __unused, char **argv __unused)
{
        int i;
        char buf[80];
        int pos;

        /* Create output files */
        if ((cfile = fopen("syntax.c", "w")) == NULL) {
                perror("syntax.c");
                exit(2);
        }
        if ((hfile = fopen("syntax.h", "w")) == NULL) {
                perror("syntax.h");
                exit(2);
        }
        fputs(writer, hfile);
        fputs(writer, cfile);

        fputs("#include <sys/cdefs.h>\n", hfile);
        fputs("#include <limits.h>\n\n", hfile);

        /* Generate the #define statements in the header file */
        fputs("/* Syntax classes */\n", hfile);
        for (i = 0 ; synclass[i].name ; i++) {
                sprintf(buf, "#define %s %d", synclass[i].name, i);
                fputs(buf, hfile);
                for (pos = strlen(buf) ; pos < 32 ; pos = (pos + 8) & ~07)
                        putc('\t', hfile);
                fprintf(hfile, "/* %s */\n", synclass[i].comment);
        }
        putc('\n', hfile);
        fputs("/* Syntax classes for is_ functions */\n", hfile);
        for (i = 0 ; is_entry[i].name ; i++) {
                sprintf(buf, "#define %s %#o", is_entry[i].name, 1 << i);
                fputs(buf, hfile);
                for (pos = strlen(buf) ; pos < 32 ; pos = (pos + 8) & ~07)
                        putc('\t', hfile);
                fprintf(hfile, "/* %s */\n", is_entry[i].comment);
        }
        putc('\n', hfile);
        fputs("#define SYNBASE (1 - CHAR_MIN)\n", hfile);
        fputs("#define PEOF -SYNBASE\n\n", hfile);
        putc('\n', hfile);
        fputs("#define BASESYNTAX (basesyntax + SYNBASE)\n", hfile);
        fputs("#define DQSYNTAX (dqsyntax + SYNBASE)\n", hfile);
        fputs("#define SQSYNTAX (sqsyntax + SYNBASE)\n", hfile);
        fputs("#define ARISYNTAX (arisyntax + SYNBASE)\n", hfile);
        putc('\n', hfile);
        output_type_macros();           /* is_digit, etc. */
        putc('\n', hfile);

        /* Generate the syntax tables. */
        fputs("#include \"parser.h\"\n", cfile);
        fputs("#include \"shell.h\"\n", cfile);
        fputs("#include \"syntax.h\"\n\n", cfile);

        fputs("/* syntax table used when not in quotes */\n", cfile);
        init("basesyntax");
        add_default();
        add("\n", "CNL");
        add("\\", "CBACK");
        add("'", "CSQUOTE");
        add("\"", "CDQUOTE");
        add("`", "CBQUOTE");
        add("$", "CVAR");
        add("}", "CENDVAR");
        add("<>();&| \t", "CSPCL");
        finish();

        fputs("\n/* syntax table used when in double quotes */\n", cfile);
        init("dqsyntax");
        add_default();
        add("\n", "CQNL");
        add("\\", "CBACK");
        add("\"", "CENDQUOTE");
        add("`", "CBQUOTE");
        add("$", "CVAR");
        add("}", "CENDVAR");
        /* ':/' for tilde expansion, '-^]' for [a\-x] pattern ranges */
        add("!*?[]=~:/-^", "CCTL");
        finish();

        fputs("\n/* syntax table used when in single quotes */\n", cfile);
        init("sqsyntax");
        add_default();
        add("\n", "CQNL");
        add("\\", "CSBACK");
        add("'", "CENDQUOTE");
        /* ':/' for tilde expansion, '-^]' for [a\-x] pattern ranges */
        add("!*?[]=~:/-^", "CCTL");
        finish();

        fputs("\n/* syntax table used when in arithmetic */\n", cfile);
        init("arisyntax");
        add_default();
        add("\n", "CQNL");
        add("\\", "CBACK");
        add("`", "CBQUOTE");
        add("\"", "CIGN");
        add("$", "CVAR");
        add("}", "CENDVAR");
        add("(", "CLP");
        add(")", "CRP");
        finish();

        fputs("\n/* character classification table */\n", cfile);
        init("is_type");
        add("0123456789", "ISDIGIT");
        add("abcdefghijklmnopqrstuvwxyz", "ISLOWER");
        add("ABCDEFGHIJKLMNOPQRSTUVWXYZ", "ISUPPER");
        add("_", "ISUNDER");
        add("#?$!-*@", "ISSPECL");
        finish();

        exit(0);
}


/*
 * Output the header and declaration of a syntax table.
 */

static void
init(const char *name)
{
        fprintf(hfile, "extern const char %s[];\n", name);
        fprintf(cfile, "const char %s[SYNBASE + CHAR_MAX + 1] = {\n", name);
}


static void
add_one(const char *key, const char *type)
{
        fprintf(cfile, "\t[SYNBASE + %s] = %s,\n", key, type);
}


/*
 * Add default values to the syntax table.
 */

static void
add_default(void)
{
        add_one("PEOF",                "CEOF");
        add_one("CTLESC",              "CCTL");
        add_one("CTLVAR",              "CCTL");
        add_one("CTLENDVAR",           "CCTL");
        add_one("CTLBACKQ",            "CCTL");
        add_one("CTLBACKQ + CTLQUOTE", "CCTL");
        add_one("CTLARI",              "CCTL");
        add_one("CTLENDARI",           "CCTL");
        add_one("CTLQUOTEMARK",        "CCTL");
        add_one("CTLQUOTEEND",         "CCTL");
}


/*
 * Output the footer of a syntax table.
 */

static void
finish(void)
{
        fputs("};\n", cfile);
}


/*
 * Add entries to the syntax table.
 */

static void
add(const char *p, const char *type)
{
        for (; *p; ++p) {
                char c = *p;
                switch (c) {
                case '\t': c = 't';  break;
                case '\n': c = 'n';  break;
                case '\'': c = '\''; break;
                case '\\': c = '\\'; break;

                default:
                        fprintf(cfile, "\t[SYNBASE + '%c'] = %s,\n", c, type);
                        continue;
                }
                fprintf(cfile, "\t[SYNBASE + '\\%c'] = %s,\n", c, type);
        }
}


/*
 * Output character classification macros (e.g. is_digit).  If digits are
 * contiguous, we can test for them quickly.
 */

static const char *macro[] = {
        "#define is_digit(c)\t((unsigned int)((c) - '0') <= 9)",
        "#define is_eof(c)\t((c) == PEOF)",
        "#define is_alpha(c)\t((is_type+SYNBASE)[(int)c] & (ISUPPER|ISLOWER))",
        "#define is_name(c)\t((is_type+SYNBASE)[(int)c] & (ISUPPER|ISLOWER|ISUNDER))",
        "#define is_in_name(c)\t((is_type+SYNBASE)[(int)c] & (ISUPPER|ISLOWER|ISUNDER|ISDIGIT))",
        "#define is_special(c)\t((is_type+SYNBASE)[(int)c] & (ISSPECL|ISDIGIT))",
        "#define digit_val(c)\t((c) - '0')",
        NULL
};

static void
output_type_macros(void)
{
        const char **pp;

        for (pp = macro ; *pp ; pp++)
                fprintf(hfile, "%s\n", *pp);
}